Deater-Deckard, Kirby
2016-05-01
Most of the individual difference variance in the population is found within families, yet studying the processes causing this variation is difficult due to confounds between genetic and nongenetic influences. Quasi-experiments can be used to test hypotheses regarding environment exposure (e.g., timing, duration) while controlling for genetic confounds. To illustrate, two studies of cognitive self-regulation in childhood (i.e., working memory [WM], effortful control [EC], attention span/persistence [A/P]) are presented. Study 1 utilized an identical twin differences design ( N = 85 to 98 pairs) to control for genetic differences while using relative twin birth weight difference to predict relative twin difference in WM and EC. Larger relative twin difference in WM and EF was predicted by the combination of shorter gestation and larger relative birth weight difference. Study 2 utilized an adoptive sibling relative difference design ( N = 123 same-sex pairs) to control for genetic similarity while using relative sibling difference in the age at time of adoption to predict relative sibling difference in A/P. Larger relative sibling difference in A/P was predicted by the combination of larger relative difference in time in the adoptive home and age at adoption. Within-family quasi-experimental designs allow stronger inferences about hypothesized environmental influences than between-family designs permit.
Railroad classification yard design methodology study Elkhart Yard Rehabilitation : a case study
DOT National Transportation Integrated Search
1980-02-01
This interim report documents the application of a railroad classification : yard design methodology to CONRAIL's Elkhart Yard Rehabilitation. This : case study effort represents Phase 2 of a larger effort to develop a yard : design methodology, and ...
Railroad classification yard design methodology study : East Deerfield Yard, a case study
DOT National Transportation Integrated Search
1980-02-01
This interim report documents the application of a railroad classification yard design methodology to Boston and Maine's East Deerfield Yard Rehabiliation. This case study effort represents Phase 2 of a larger effort to develop a yard design methodol...
The Influence of Hoop Diameter on Aerodynamic Performance of O-Ring Paper Plane
NASA Astrophysics Data System (ADS)
Ismail, N. I.; Sharudin, Hazim; Talib, R. J.; Hassan, A. A.; Yusoff, H.
2018-05-01
The O-ring paper plane can be categorized as one of the Micro Air Vehicle (MAV) based on their characteristics and size. However, the aerodynamics performance of the O-ring paper plane was not fully discovered by previous researchers due to its aerodynamics complexity and various hoop diameters. Thus, the objective of this research is to study the influence of hoop diameters towards the aerodynamics performance of O-ring paper plane. In this works, three types of O-ring paper plane known as Design 1, 2 and 3 with different hoop diameter were initially developed by using the ANSYS-Design Modeler. All the design was analyzed based on aerodynamic simulations works executed on ANSYS-CFX solver. The results suggested that Design 3 (with larger hoop size) produced better CL, CLmax and AoAstall magnitude compared to other design. In fact, O-ring paper plane with larger hoop size configurations showed potential in providing at least 5.2% and 5.9% better performance in stability (ΔCM/ΔCL) and aerodynamic efficiency (CL/CDmax), respectively. Despite the advantages found in lift performances, however, O-ring paper plane with larger hoop size configurations slightly suffered from larger drag increment (CDincrement) compared to smaller hoop size configurations. Based on these results, it can be presumed that O-Ring paper plane with larger hoop sizes contributed into better lift, stability and aerodynamic efficiency performances but slightly suffered from larger drag penalty.
NASA Technical Reports Server (NTRS)
Kim, Jongmin; Zukic, Muamer; Wilson, Michele M.; Park, Jung Ho; Torr, Douglas G.
1994-01-01
Good theoretical designs of far ultraviolet polarizers have been reported using a MgF2/Al/MgF2 three layer structure on a thick Al layer as a substrate. The thicknesses were determined to induce transmission and absorption of p-polarized light. In these designs Al optical constants were used from films produced in ultrahigh vacuum (UHV: 10(exp -10) torr). Reflectance values for polarizers fabricated in a conventional high vacuum (p approx. 10(exp -6 torr)) using the UHV design parameters differed dramatically from the design predictions. Al is a highly reactive material and is oxidized even in a high vacuum chamber. In order to solve the problem other metals have been studied. It is found that a larger reflectance difference is closely related to higher amplitude and larger phase difference of Fresnel reflection coefficients between two polarizations at the boundary of MgF2/metal. It is also found that for one material a larger angle of incidence from the surface normal brings larger amplitude and phase difference. Be and Mo are found good materials to replace Al. Polarizers designed for 121.6 nm with Be at 60 deg and with Mo at 70 deg are shown as examples.
An Opening: Graphic Design's Discursive Spaces.
ERIC Educational Resources Information Center
Blauvelt, Andrew
1994-01-01
Introduces a special issue on critical histories of graphic design with a review of the particular problems identified with the history of graphic design as a field of study and the emerging discipline of graphic design history. Makes a case for the examination of graphic design through its relationships with larger discourses. (SR)
ERIC Educational Resources Information Center
Atman, Cindy; Kilgore, Deborah; McKenna, Ann
2009-01-01
This analysis, that utilizes data from part of the Academic Pathways Study (APS) of the Center for the Advancement of Engineering Education (CAEE), found that as a result of taking a course in engineering design and/or studying engineering for four years, students acquire engineering design language that is common to a larger community of practice…
ERIC Educational Resources Information Center
Taylor, Joseph; Kowalski, Susan; Getty, Stephen; Wilson, Christopher; Carlson, Janet
2011-01-01
This research is part of a larger, IES-funded study titled: "Measuring the Efficacy and Student Achievement of Research-based Instructional Materials in High School Multidisciplinary Science" (Award # R305K060142). The larger study seeks to use a cluster-randomized trial design, with schools as the unit of assignment, to make causal…
A mixed method pilot study: the researchers' experiences.
Secomb, Jacinta M; Smith, Colleen
2011-08-01
This paper reports on the outcomes of a small well designed pilot study. Pilot studies often disseminate limited or statistically meaningless results without adding to the body knowledge on the comparative research benefits. The design a pre-test post-test group parallel randomised control trial and inductive content analysis of focus group transcripts was tested specifically to increase outcomes in a proposed larger study. Strategies are now in place to overcome operational barriers and recruitment difficulties. Links between the qualitative and quantitative arms of the proposed larger study have been made; it is anticipated that this will add depth to the final report. More extensive reporting on the outcomes of pilot studies would assist researchers and increase the body of knowledge in this area.
ERIC Educational Resources Information Center
Smith, Kennon M.
2013-01-01
This article reports on a portion of a larger qualitative study focused on a group of interior design students' perceptions of their educational experiences. Twelve interior design students enrolled in their final studio course participated in interviews intended to elicit their perceptions of key barriers encountered during their undergraduate…
Factors Affecting Cheating-Behavior at Undergraduate-Engineering
ERIC Educational Resources Information Center
Starovoytova, Diana; Namango, Saul
2016-01-01
This study is a fraction of a larger research on cheating in exams at the School of Engineering (SOE). The study design used a descriptive survey approach and a document analysis. A designed confidential self report questioner was applied as the main instrument for this study, with the sample size of 100 subjects, and a response rate of 95%. The…
Effect of Subelement Spacing in Rrp Nb3Sn Deformed Strands
NASA Astrophysics Data System (ADS)
Barzi, E.; Turrioni, D.; Alsharo'a, M.; Field, M.; Hong, S.; Parrell, J.; Yamada, R.; Zhang, Y.; Zlobin, A. V.
2008-03-01
The Restacked Rod Process (RRP) is the Nb3Sn strand technology presently producing the largest critical current densities at 4.2 K and 12 T. However, when subject to transverse plastic deformation, RRP subelements (SE) merge into each other, creating larger filaments with a somewhat continuous barrier. In this case, the strand sees a larger effective filament size and its instability can dramatically increase locally leading to a cable quench. To reduce and possibly eliminate this effect, Oxford Instruments Superconducting Technology (OST) developed for FNAL a modified RRP strand design with larger Cu spacing between SE's arranged in a 60/61 array. Strand samples of this design with sizes from 0.7 to 1 mm were first evaluated for transport current properties. A comparison study was then performed between the regular 54/61 and the modified 60/61 design using 0.7 mm round and deformed strands. Finite element modeling of the deformed strands was also performed with ANSYS.
Witnessing of Cheating-in-Exams Behavior and Factors Sustaining Integrity
ERIC Educational Resources Information Center
Starovoytova, Diana; Arimi, Milton
2017-01-01
This study is a fraction of a larger research on cheating, at the School of Engineering (SOE). The study design used a descriptive survey approach and a document analysis. A designed confidential self-report questioner was used as the main instrument, for this study, with the sample size of 100 subjects and response rate of 95%. The tool was…
Reproducibility of preclinical animal research improves with heterogeneity of study samples
Vogt, Lucile; Sena, Emily S.; Würbel, Hanno
2018-01-01
Single-laboratory studies conducted under highly standardized conditions are the gold standard in preclinical animal research. Using simulations based on 440 preclinical studies across 13 different interventions in animal models of stroke, myocardial infarction, and breast cancer, we compared the accuracy of effect size estimates between single-laboratory and multi-laboratory study designs. Single-laboratory studies generally failed to predict effect size accurately, and larger sample sizes rendered effect size estimates even less accurate. By contrast, multi-laboratory designs including as few as 2 to 4 laboratories increased coverage probability by up to 42 percentage points without a need for larger sample sizes. These findings demonstrate that within-study standardization is a major cause of poor reproducibility. More representative study samples are required to improve the external validity and reproducibility of preclinical animal research and to prevent wasting animals and resources for inconclusive research. PMID:29470495
Students at the Center: Feminist Assessment.
ERIC Educational Resources Information Center
Musil, Caryn McTighe, Ed.
This publication is designed to facilitate program assessment involving women's studies courses by setting feminist principles of assessment in the context of the larger assessment movement. It features innovative assessment designs, a variety of methodological approaches, and practical advice about how to conduct a productive assessment project…
Using Teacher Impression Journals to Improve Intervention Effectiveness
ERIC Educational Resources Information Center
Yu, SeonYeong; Ostrosky, Michaelene M.; Meyer, Lori E.; Favazza, Paddy C.; Mouzourou, Chryso; van Luling, Lisa
2016-01-01
This article describes the use of "Teacher Impression Journals" during a larger study that examined the efficacy of an intervention program designed to promote kindergarteners' positive attitudes toward peers with disabilities (i.e., the "Special Friends" program). The journals were designed to gather information about…
Cultural Resources Survey of the Morgan City and Vicinity Hurricane Protection Project.
1985-12-30
22 5 RESEARCH DESIGN ...................................... 26 Introduction ..................................... 26 Theoretical... designed to enable the construction or enlargement of protective levees and drainage structures for both the Franklin and Morgan City areas, in St...the larger project area was conducted during May-July, 1985, by R. Christopher Goodwin and Associates, Inc. The research design for this study
Jiang, Yingxu; Zhao, Jinzhe; Li, Weitao; Yang, Yamin; Liu, Jia; Qian, Zhiyu
2017-11-01
Investigation of the structures and properties of antennas is important in the design of microwave ablation (MWA) system. In this study, we studied the performance of the novel tri- and single-slot antennas with frequency of 433 MHz in ex vivo conditions. The dielectric properties of liver tissue under different thermal coagulation levels were explored, which was beneficial to evaluate ablation condition of tissue and simulate temperature field. Then, the performances of the antennas were analyzed by using numerical method based on finite element method (FEM). It indicated that the present antennas with frequency of 433 MHz could produce a gourd-shaped MWA area with a longer length. Compared to antenna with frequency of 2450 MHz, the designed single-slot antenna could obtain the larger MWA area. In addition, the multiple-point ablations and a larger MWA area could be achieved simultaneously by using the present tri-slot antenna. This study has a potential for the innovative design of MWA antenna for treatment of liver tumor with a large range and a long length.
Conducting pilot and feasibility studies.
Cope, Diane G
2015-03-01
Planning a well-designed research study can be tedious and laborious work. However, this process is critical and ultimately can produce valid, reliable study findings. Designing a large-scale randomized, controlled trial (RCT)-the gold standard in quantitative research-can be even more challenging. Even the most well-planned study potentially can result in issues with research procedures and design, such as recruitment, retention, or methodology. One strategy that may facilitate sound study design is the completion of a pilot or feasibility study prior to the initiation of a larger-scale trial. This article will discuss pilot and feasibility studies, their advantages and disadvantages, and implications for oncology nursing research. .
ERIC Educational Resources Information Center
Ifenthaler, Dirk; Gosper, Maree
2014-01-01
This paper introduces the MAPLET framework that was developed to map and link teaching aims, learning processes, learner expertise and technologies. An experimental study with 65 participants is reported to test the effectiveness of the framework as a guide to the design of lessons embedded within larger units of study. The findings indicate the…
Statistical Analysis of CFD Solutions from 2nd Drag Prediction Workshop
NASA Technical Reports Server (NTRS)
Hemsch, M. J.; Morrison, J. H.
2004-01-01
In June 2001, the first AIAA Drag Prediction Workshop was held to evaluate results obtained from extensive N-Version testing of a series of RANS CFD codes. The geometry used for the computations was the DLR-F4 wing-body combination which resembles a medium-range subsonic transport. The cases reported include the design cruise point, drag polars at eight Mach numbers, and drag rise at three values of lift. Although comparisons of the code-to-code medians with available experimental data were similar to those obtained in previous studies, the code-to-code scatter was more than an order-of-magnitude larger than expected and far larger than desired for design and for experimental validation. The second Drag Prediction Workshop was held in June 2003 with emphasis on the determination of installed pylon-nacelle drag increments and on grid refinement studies. The geometry used was the DLR-F6 wing-body-pylon-nacelle combination for which the design cruise point and the cases run were similar to the first workshop except for additional runs on coarse and fine grids to complement the runs on medium grids. The code-to-code scatter was significantly reduced for the wing-body configuration compared to the first workshop, although still much larger than desired. However, the grid refinement studies showed no sign$cant improvement in code-to-code scatter with increasing grid refinement.
Concept and performance study of turbocharged solid propellant ramjet
NASA Astrophysics Data System (ADS)
Li, Jiang; Liu, Kai; Liu, Yang; Liu, Shichang
2018-06-01
This study proposes a turbocharged solid propellant ramjet (TSPR) propulsion system that integrates a turbocharged system consisting of a solid propellant (SP) air turbo rocket (ATR) and the fuel-rich gas generator of a solid propellant ramjet (SPR). First, a suitable propellant scheme was determined for the TSPR. A solid hydrocarbon propellant is used to generate gas for driving the turbine, and a boron-based fuel-rich propellant is used to provide fuel-rich gas to the afterburner. An appropriate TSPR structure was also determined. The TSPR's thermodynamic cycle was analysed to prove its theoretical feasibility. The results showed that the TSPR's specific cycle power was larger than those of SP-ATR and SPR and thermal efficiency was slightly less than that of SP-ATR. Overall, TSPR showed optimal performance in a wide flight envelope. The specific impulses and specific thrusts of TSPR, SP-ATR, and SPR in the flight envelope were calculated and compared. TSPR's flight envelope roughly overlapped that of SP-ATR, its specific impulse was larger than that of SP-ATR, and its specific thrust was larger than those of SP-ATR and SPR. Attempts to improve the TSPR off-design performance prompted our proposal of a control plan for off-design codes in which both the turbocharger corrected speed and combustor excess gas coefficient are kept constant. An off-design performance model was established by analysing the TSPR working process. We concluded that TSPR with a constant corrected speed had wider flight envelope, higher thrust, and higher specific impulse than TSPR with a constant physical speed determined by calculating the performance of off-design TSPR codes under different control plans. The results of this study can provide a reference for further studies on TSPRs.
VISUAL AND AUDIO PRESENTATION IN MACHINE PROGRAMED INSTRUCTION. FINAL REPORT.
ERIC Educational Resources Information Center
ALLEN, WILLIAM H.
THIS STUDY WAS PART OF A LARGER RESEARCH PROGRAM AIMED TOWARD DEVELOPMENT OF PARADIGMS OF MESSAGE DESIGN. OBJECTIVES OF THREE PARALLEL EXPERIMENTS WERE TO EVALUATE INTERACTIONS OF PRESENTATION MODE, PROGRAM TYPE, AND CONTENT AS THEY AFFECT LEARNER CHARACTERISTICS. EACH EXPERIMENT USED 18 TREATMENTS IN A FACTORIAL DESIGN WITH RANDOMLY SELECTED…
NASA Technical Reports Server (NTRS)
Coykendall, R. E.; Curry, J. K.; Domke, A. E.; Madsen, S. E.
1976-01-01
Economic studies were conducted for three general fuel conserving options: (1) improving fuel consumption characteristics of existing aircraft via retrofit modifications; (2) introducing fuel efficient derivations of existing production aircraft and/or introducing fuel efficient, current state-of-the-art new aircraft; and (3) introducing an advanced state-of-the-art turboprop airplane. These studies were designed to produce an optimum airline fleet mix for the years 1980, 1985 and 1990. The fleet selected accommodated a normal growth market by introducing somewhat larger aircraft while solving for maximum departure frequencies and a minimum load factor corresponding to a 15% investment hurdle rate. Fuel burnt per available-seat-mile flown would drop 22% from 1980 to 1990 due to the use of more fuel efficient aircraft designs, larger average aircraft size, and increased seating density. An inflight survey was taken to determine air traveler attitudes towards a new generation of advanced turboprops.
A Study of Crowd Ability and its Influence on Crowdsourced Evaluation of Design Concepts
2014-05-01
identifies the experts from the crowd, under the assumptions that ( 1 ) experts do exist and (2) only experts have consistent evaluations. These assumptions...for design evaluation tasks . Keywords: crowdsourcing, design evaluation, sparse evaluation ability, machine learning ∗Corresponding author. 1 ...intelligence” of a much larger crowd of people with diverse backgrounds [ 1 ]. Crowdsourced evaluation, or the delegation of an eval- uation task to a
Area Handbook Series: Zimbabwe: A Country Study
1982-08-01
not be construed as an official Department of the Army position, policy, or decision, unless so designated by other official documentation. The authors...see table A). Claimed in the late nineteenth century by Cecil Rhodes’ British South Africa Company as part of a larger territory designated Rhodesia...has used the term Rhodesia except in situations where the historical significance of the other designations appears more appropriate to the reader’s
The Heritability of General Cognitive Ability: A Within-Family Adoption Design
ERIC Educational Resources Information Center
Petrill, Stephen A.; Deater-Deckard, Kirby
2004-01-01
The current study employed a within-family adoption design to examine the genetic and environmental influences on general cognitive ability. A sample of 51 families with biological (mean age = 9.83 years, S.D. = 2.81) and adoptive children (mean age = 6.86, S.D. = 1.92) was selected from the larger "Northeast-Northwest Collaborative Adoption…
DOT National Transportation Integrated Search
2016-12-15
Heavy vehicles have a much larger effect on the flow of a roundabout than a passenger car, and therefore they must be accounted for in the design (Transportation Research Board). Very few studies have looked at the effect of heavy vehicles on the flo...
Definition and Measurement of Complexity in the Context of Safety Assurance
2016-11-01
design for each sys- tem and on a larger design from a NASA report. The complexity measurement must be matched to available review time to determine...ARP4754A to Flight Critical Systems.” NASA , 2015. http://ntrs.nasa.gov/search.jsp?R=20160001634 [Rayner 2016] Rayner, Keith; Schotter, Elizabeth R...systems. We tested it on a second design for each system and on a larger design from a NASA report. The complexity measurement must be matched to
NASA Astrophysics Data System (ADS)
Kozicki, Janek; Kozicka, Joanna
Human missions to Mars are a special kind of space missions due to their long duration. The human aspect of such missions becomes as important as the technological one. The need for a human friendly and comfortable habitat arises. Studies of human behavior in ICEs have shown that larger groups of people mean a lower occurrence of conflicts. However, for a larger crew a larger habitat has to be designed -a Martian base. The research deals with psychological, sociological and technological aspects influencing the architectural design of a Martian Base. Extreme conditions present on Mars demand a partic-ular approach to technological and architectural design. To reduce the cost of building a bigger habitat, low cost solutions have been inquired into. A series of analyses has been performed to identify the best architectural solutions for a Martian base. A review of existing technologies and extreme condition habitats (both terrestrial and extraterrestrial) has revealed solutions that are the most reliable and efficient ones. Additionally, innovative technologies have been analyzed in search of the best candidates for actual base construction. Low cost solutions have been prioritized in the process. An in-depth study of architectural problems inherent in the design of a Martian base has resulted in a number of guidelines for the architect. The main ones are introduced in this review. Based on them, several concepts have been drafted as examples of user-friendly and aesthetically pleasing habitats. They are discussed in the following order: habitats made of domes, those built around greenhouses and those situated in sloping terrain. One of them is presented in detail, including interior design.
Könings, Karen D; Brand-Gruwel, Saskia; Elen, Jan
2012-09-01
Students' perspective on education is of crucial importance for its effectivity, but students' opinions are seldom acknowledged by teachers and designers. Student participation in the educational design process could be a suitable tool to better take students' preferences into account. However, for effective participatory design, it is necessary to know whether students have stable preferences for the design of their education. Changeability of preferences would require a more continuing design process allowing continuous adaptations. This longitudinal survey study aimed to determine the changeability over time of students' preferences for different aspects of a learning environment. Additionally, causes of possible changes in preferences are investigated. The participants were 1,335 high school students of five schools for secondary education in the Netherlands, joining this study during a period of 2 years. Data about students' preferences were collected at three moments, using the Inventory of Perceived Study Environment Extended. Learning-related student characteristics, such as processing strategies and motivational orientations, were measured with the Inventory of Learning Styles. Additionally, data on learning performances were collected. The results showed stability on preferences for almost all studied characteristics of the learning environment. Particularly remarkable was a drop in desirability for student autonomy. This was larger for students with a certificate-oriented motivation and smaller for self-regulated students. Additionally, poorly performing students had a larger decrease in preference for autonomy. The stability on most aspects supports that participatory design might result in fairly stable instructional designs, although caution is needed with respect to student autonomy. ©2011 The British Psychological Society.
ERIC Educational Resources Information Center
Burkholder, Gary J.; Harlow, Lisa L.
2003-01-01
Tested a model of HIV behavior risk, using a fully cross-lagged, longitudinal design to illustrate the analysis of larger structural equation models. Data from 527 women who completed a survey at three time points show excellent fit of the model to the data. (SLD)
NASA Technical Reports Server (NTRS)
Fujiwara, Gustavo; Bragg, Mike; Triphahn, Chris; Wiberg, Brock; Woodard, Brian; Loth, Eric; Malone, Adam; Paul, Bernard; Pitera, David; Wilcox, Pete;
2017-01-01
This report presents the key results from the first two years of a program to develop experimental icing simulation capabilities for full-scale swept wings. This investigation was undertaken as a part of a larger collaborative research effort on ice accretion and aerodynamics for large-scale swept wings. Ice accretion and the resulting aerodynamic effect on large-scale swept wings presents a significant airplane design and certification challenge to air frame manufacturers, certification authorities, and research organizations alike. While the effect of ice accretion on straight wings has been studied in detail for many years, the available data on swept-wing icing are much more limited, especially for larger scales.
Experimental Design: Review and Comment.
1984-02-01
increasing the chance of finding an optimal exact design. The space- saving methods make it possible to study larger problems. Galil and Kiefer also...building along this line is limited; see, for example, Box and Hunter (1962), Hunter and Mezaki (1964), Draper and Herzberg (1971), and Box and Draper (1982...criterion a requirement that p/n not be too large. Draper and Herzberg (1979) extended the work of Box and Draper (1975) by studying the effect of
Recognition Memory for Braille or Spoken Words: An fMRI study in Early Blind
Burton, Harold; Sinclair, Robert J.; Agato, Alvin
2012-01-01
We examined cortical activity in early blind during word recognition memory. Nine participants were blind at birth and one by 1.5 yrs. In an event-related design, we studied blood oxygen level-dependent responses to studied (“old”) compared to novel (“new”) words. Presentation mode was in Braille or spoken. Responses were larger for identified “new” words read with Braille in bilateral lower and higher tier visual areas and primary somatosensory cortex. Responses to spoken “new” words were larger in bilateral primary and accessory auditory cortex. Auditory cortex was unresponsive to Braille words and occipital cortex responded to spoken words but not differentially with “old”/“new” recognition. Left dorsolateral prefrontal cortex had larger responses to “old” words only with Braille. Larger occipital cortex responses to “new” Braille words suggested verbal memory based on the mechanism of recollection. A previous report in sighted noted larger responses for “new” words studied in association with pictures that created a distinctiveness heuristic source factor which enhanced recollection during remembering. Prior behavioral studies in early blind noted an exceptional ability to recall words. Utilization of this skill by participants in the current study possibly engendered recollection that augmented remembering “old” words. A larger response when identifying “new” words possibly resulted from exhaustive recollecting the sensory properties of “old” words in modality appropriate sensory cortices. The uniqueness of a memory role for occipital cortex is in its cross-modal responses to coding tactile properties of Braille. The latter possibly reflects a “sensory echo” that aids recollection. PMID:22251836
Recognition memory for Braille or spoken words: an fMRI study in early blind.
Burton, Harold; Sinclair, Robert J; Agato, Alvin
2012-02-15
We examined cortical activity in early blind during word recognition memory. Nine participants were blind at birth and one by 1.5years. In an event-related design, we studied blood oxygen level-dependent responses to studied ("old") compared to novel ("new") words. Presentation mode was in Braille or spoken. Responses were larger for identified "new" words read with Braille in bilateral lower and higher tier visual areas and primary somatosensory cortex. Responses to spoken "new" words were larger in bilateral primary and accessory auditory cortex. Auditory cortex was unresponsive to Braille words and occipital cortex responded to spoken words but not differentially with "old"/"new" recognition. Left dorsolateral prefrontal cortex had larger responses to "old" words only with Braille. Larger occipital cortex responses to "new" Braille words suggested verbal memory based on the mechanism of recollection. A previous report in sighted noted larger responses for "new" words studied in association with pictures that created a distinctiveness heuristic source factor which enhanced recollection during remembering. Prior behavioral studies in early blind noted an exceptional ability to recall words. Utilization of this skill by participants in the current study possibly engendered recollection that augmented remembering "old" words. A larger response when identifying "new" words possibly resulted from exhaustive recollecting the sensory properties of "old" words in modality appropriate sensory cortices. The uniqueness of a memory role for occipital cortex is in its cross-modal responses to coding tactile properties of Braille. The latter possibly reflects a "sensory echo" that aids recollection. Copyright © 2011 Elsevier B.V. All rights reserved.
Design of the Space Station Freedom power system
NASA Technical Reports Server (NTRS)
Thomas, Ronald L.; Hallinan, George J.
1989-01-01
The design of Space Station Freedom's electric power system (EPS) is reviewed, highlighting the key design goals of performance, low cost, reliability and safety. Tradeoff study results that illustrate the competing factors responsible for many of the more important design decisions are discussed. When Freedom's EPS is compared with previous space power designs, two major differences stand out. The first is the size of the EPS, which is larger than any prior system. The second major difference between the EPS and other space power designs is the indefinite expected life of Freedom; 30 years has been used for life-cycle-cost calculations.
NASA Technical Reports Server (NTRS)
Adams, K. M.; Lucas, J. J.
1977-01-01
The development of a frame/stringer/skin fabrication technique for composite airframe construction was studied as a low cost approach to the manufacturer of larger helicopter airframe components. A center cabin aluminum airframe section of the Sikorsky CH-53D, was selected for evaluation as a composite structure. The design, as developed, is composed of a woven KEVLAR R-49/epoxy skin and graphite/epoxy frames and stringers. The single cure concept is made possible by the utilization of pre-molded foam cores, over which the graphite/epoxy pre-impregnated frame and stringer reinforcements are positioned. Bolted composite channel sections were selected as the optimum joint construction. The applicability of the single cure concept to larger realistic curved airframe sections, and the durability of the composite structure in a realistic spectrum fatigue environment, was described.
Comparative studies of perceived vibration strength for commercial mobile phones.
Lee, Heow Pueh; Lim, Siak Piang
2014-05-01
A mobile phone, also known as cell phone or hand phone, is among the most popular electrical devices used by people all over the world. The present study examines the vibration perception of mobile phones by co-relating the relevant design parameters such as excitation frequency, and size and mass of mobile phones to the vibration perception survey by volunteers. Five popular commercially available mobile phone models were tested. The main findings for the perception surveys were that higher vibration frequency and amplitude of the peak acceleration would result in stronger vibration perception of the mobile phones. A larger contact surface area with the palms and figures, higher peak acceleration and the associated larger peak inertia force may be the main factors for the relatively higher vibration perception. The future design for the vibration alert of the mobile phones is likely to follow this trend. Copyright © 2013 Elsevier Ltd and The Ergonomics Society. All rights reserved.
Communication: The Study of Human Interaction.
ERIC Educational Resources Information Center
Mortensen, C. David
Designed to provide a comprehensive and broadly based introduction to the study of human communication, this book presents the concept of communication as interrelated constituent processes that operate at varying levels of complexity and acquire significance only in the context of larger intrapersonal, interpersonal, or socio-cultural systems of…
Gender Differences in Attitudes toward Environmental Science
ERIC Educational Resources Information Center
Carrier, Sarah J.
2007-01-01
This study examined the role of gender in the areas of environmental education that included environmental knowledge, attitudes, behaviors, and comfort levels in the outdoors. The current study was part of a larger study designed to explore the effects of a treatment that consisted of 14 weeks of outdoor lessons conducted in the schoolyard as…
Are Consumer-Directed Home Care Beneficiaries Satisfied? Evidence from Washington State
ERIC Educational Resources Information Center
Wiener, Joshua M.; Anderson, Wayne L.; Khatutsky, Galina
2007-01-01
Purpose: This study analyzed the effect of consumer-directed versus agency-directed home care on satisfaction with paid personal assistance services among Medicaid beneficiaries in Washington State. Design and Methods: The study analyzed a survey of 513 Medicaid beneficiaries receiving home- and community-based services. As part of a larger study,…
Assessing R&D Opportunities for Clean Energy Technologies - Continuum
Magazine | NREL photo of wind turbine blades being transported by a train through a city. As manufacturing opportunities. Because transportation is complicated, larger blades are typically manufactured advance, larger blade designs may increase U.S.-based manufacturing opportunities. Larger blades tend to
DOE Office of Scientific and Technical Information (OSTI.GOV)
Coykendall, R.E.; Curry, J.K.; Domke, A.E.
1976-06-01
Economic studies were conducted for three general fuel-conserving options: (1) improving fuel-consumption characteristics of existing aircraft via retrofit modifications; (2) introducing fuel-efficient derivations of existing production aircraft and/or introducing fuel efficient, current state-of-the-art new aircraft; and (3) introducing an advanced state-of-the-art turboprop airplane. These studies were designed to produce an optimum airline fleet mix for the years 1980, 1985 and 1990. The fleet selected accommodated a normal growth market by introducing somewhat larger aircraft while solving for maximum departure frequencies and a minimum load factor corresponding to a 15% investment hurdle rate. Fuel burnt per available-seat-mile flown would drop 22%more » from 1980 to 1990 due to the use of more fuel efficient aircraft designs, larger average aircraft size, and increased seating density. An inflight survey was taken to determine air traveler attitudes towards a new generation of advanced turboprops. (Author) (GRA)« less
Changing Trends in LIS Job Advertisements
ERIC Educational Resources Information Center
Wise, Sharyn; Henninger, Maureen; Kennan, Mary Anne
2011-01-01
The study reported in this paper is part of a larger program of studies designed to review and renew the curricula of Library and Information Science (LIS) and the broader Information Management (IM) courses. This paper analysed job advertisements as readily accessible indicators of the knowledge, skills, and competencies required of IPs by…
Factors Influencing Development of Perfectionism in Gifted College Students
ERIC Educational Resources Information Center
Speirs-Neumeister, Kristie L.
2004-01-01
This study is part of a larger research investigation of perfectionism in gifted college students. Employing a qualitative interview design, this study examined factors contributing to the development of two dimensions of perfectionism, socially prescribed and self-oriented, in gifted college students. Findings indicated that exposure to parental…
The Organizational Realities of Student Affairs: A Political Perspective
ERIC Educational Resources Information Center
Shinn, Jeremiah B.
2015-01-01
The purpose of this study was to understand the organizational functions of student-affairs at Indiana University and to understand the nature of the conflict between student-affairs and the larger organization. This study utilized the case-study research design. Much of the data collected and analyzed during this case study were of a historical…
NASA Astrophysics Data System (ADS)
Berzak Hopkins, L.; Divol, L.; Lepape, S.; Meezan, N. B.; Dewald, E.; Ho, D.; Khan, S.; Pak, A.; Ralph, J.; Ross, J. S.
2016-10-01
Recent simulation-based and experimental work using high-density carbon ablators in unlined uranium hohlraums with 0.3 mg/cc helium fill have demonstrated round implosions with minimal evolution of Legendre moment P2 during burn. To extend this promising work, design studies have been performed to explore potential performance improvements with larger capsules, while maintaining similar case-to-capsule target ratios. We present here the results of these design studies, which will motivate a series of upcoming experiments at the National Ignition Facility. Prepared by LLNL under Contract DE-AC52-07NA27344.
The Rocket Equation Improvement under ICF Implosion Experiment
NASA Astrophysics Data System (ADS)
Wang, Yanbin; Zheng, Zhijian
2013-10-01
The ICF explosion process has been studied in details. The rocket equation has been improved in explosive process by introducing the pressure parameter of fuel. Some methods could be drawn by the improved rocket equation. And the methods could be used to improve ICF target design, driving pulse design and experimental design. The First is to increase ablation pressure. The second is to decrease pressure of fuel. The third is to use larger diameter of target sphere. And the forth is to a shorten driving pulse.
Design and implementation of the ESL compact range underhung bridge crane
NASA Technical Reports Server (NTRS)
Shamansky, H. T.; Dominek, A. K.; Burnside, W. D.
1987-01-01
As the indoor compact range technology has continued to increase, the need to handle larger and heavier targets has also increased. This need for target lifting and handling prompted the feasibility study of the use of an underhung bridge crane to be installed in the ESL (ElectroScience Laboratory, Ohio State University) compact range. This report documents both the design of the underhung bridge crane that was installed and the implementation of the design in the actual installation of the crane.
Measurements of the frame acoustic properties of porous and granular materials
NASA Astrophysics Data System (ADS)
Park, Junhong
2005-12-01
For porous and granular materials, the dynamic characteristics of the solid component (frame) are important design factors that significantly affect the material's acoustic properties. The primary goal of this study was to present an experimental method for measuring the vibration characteristics of this frame. The experimental setup was designed to induce controlled vibration of the solid component while minimizing the influence from coupling between vibrations of the fluid and the solid component. The Biot theory was used to verify this assumption, taking the two dilatational wave propagations and interactions into account. The experimental method was applied to measure the dynamic properties of glass spheres, lightweight microspheres, acoustic foams, and fiberglass. A continuous variation of the frame vibration characteristics with frequency similar to that of typical viscoelastic materials was measured. The vibration amplitude had minimal effects on the dynamic characteristics of the porous material compared to those of the granular material. For the granular material, materials comprised of larger particles and those under larger vibration amplitudes exhibited lower frame wave speeds and larger decay rates.
Lederman, Yitzchok S.; Balucani, Clotilde; Lazar, Jason; Steinberg, Leah; Gugger, James; Levine, Steven R.
2014-01-01
Background QT dispersion (QTd) has been proposed as an indirect ECG measure of heterogeneity of ventricular repolarization. The predictive value of QTd in acute stroke remains controversial. We aimed to clarify the relationship between QTd and acute stroke and stroke prognosis. Methods A systematic review of the literature was performed using pre-specified medical subjects heading (MeSH) terms, Boolean logic and the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. Eligible studies (a) included ischemic or hemorrhagic stroke and (b) provided QTd measurements. Results Two independent reviewers identified 553 publications. Sixteen articles were included in the final analysis. There were a total of 888 stroke patients: 59% ischemic and 41% hemorrhagic. There was considerable heterogeneity in study design, stroke subtypes, ECG assessment-time, control groups and comparison groups. Nine studies reported a significant association between acute stroke and baseline QTd. Two studies reported that QTd increases are specifically related to hemorrhagic strokes, involvement of the insular cortex, right-side lesions, larger strokes, and increases in 3, 4-dihydroxyphenylethylene glycol in hemorrhagic stroke. Three studies reported QTd to be an independent predictor of stroke mortality. One study each reported increases in QTd in stroke patients who developed ventricular arrhythmias and cardiorespiratory compromise. Conclusions There are few well-designed studies and considerable variability in study design in addressing the significance of QTd in acute stroke. Available data suggest that stroke is likely to be associated with increased QTd. While some evidence suggests a possible prognostic role of QTd in stroke, larger and well-designed studies need to confirm these findings. PMID:25282188
Research notes : recycling roads and roofs.
DOT National Transportation Integrated Search
2010-06-01
One objective of the larger study is to develop recommendations for a design process for selecting the grade of virgin asphalt binder for HMAC mixtures containing RAP or RAS, or combinations of RAP and RAS, such that the blended binder meets the desi...
Spine device clinical trials: design and sponsorship.
Cher, Daniel J; Capobianco, Robyn A
2015-05-01
Multicenter prospective randomized clinical trials represent the best evidence to support the safety and effectiveness of medical devices. Industry sponsorship of multicenter clinical trials is purported to lead to bias. To determine what proportion of spine device-related trials are industry-sponsored and the effect of industry sponsorship on trial design. Analysis of data from a publicly available clinical trials database. Clinical trials of spine devices registered on ClinicalTrials.gov, a publicly accessible trial database, were evaluated in terms of design, number and location of study centers, and sample size. The relationship between trial design characteristics and study sponsorship was evaluated using logistic regression and general linear models. One thousand six hundred thrity-eight studies were retrieved from ClinicalTrials.gov using the search term "spine." Of the 367 trials that focused on spine surgery, 200 (54.5%) specifically studied devices for spine surgery and 167 (45.5%) focused on other issues related to spine surgery. Compared with nondevice trials, device trials were far more likely to be sponsored by the industry (74% vs. 22.2%, odds ratio (OR) 9.9 [95% confidence interval 6.1-16.3]). Industry-sponsored device trials were more likely multicenter (80% vs. 29%, OR 9.8 [4.8-21.1]) and had approximately four times as many participating study centers (p<.0001) and larger sample sizes. There were very few US-based multicenter randomized trials of spine devices not sponsored by the industry. Most device-related spine research is industry-sponsored. Multicenter trials are more likely to be industry-sponsored. These findings suggest that previously published studies showing larger effect sizes in industry-sponsored vs. nonindustry-sponsored studies may be biased as a result of failure to take into account the marked differences in design and purpose. Copyright © 2015 Elsevier Inc. All rights reserved.
ERIC Educational Resources Information Center
Salonen, Anssi; Kärkkäinen, Sirpa; Keinonen, Tuula
2018-01-01
The aim of this study was to investigate how career-related instruction implemented in secondary school chemistry education concerning water issues influences students' career awareness and their interest towards science learning. This case study is part of a larger design-based research study for the EU-MultiCO project, which focuses on promoting…
ERIC Educational Resources Information Center
Shobola, A. A.; Nwoha, P. C.
2013-01-01
This piece of article is culled from a larger study. The study investigated the relationship between family-work conflict, Type-E personality and stress in married female Nigerian University Administrators. The study adopted ex-post facto design. The sample consisted of 800 female administrators in the senior cadre of executive/administrative…
How to Get the Recommender Out of the Lab?
NASA Astrophysics Data System (ADS)
Picault, Jérome; Ribière, Myriam; Bonnefoy, David; Mercer, Kevin
A personalised system is a complex system made of many interacting parts, from data ingestion to presenting the results to the users. A plethora of methods, tools, algorithms and approaches exist for each piece of such a system: many data and metadata processing methods, many user models, many filtering techniques, many accuracy metrics, many personalisation levels. In addition, a realworld recommender is a piece of an even larger and more complex environment on which there is little control: often the recommender is part of a larger application introducing constraints for the design of the recommender, e.g. the data may not be in a suitable format, or the environment may impose some architectural or privacy constraints. This can make the task of building such a recommender system daunting, and it is easy to make errors. Based on the experience of the authors and the study of other works, this chapter intends to be a guide on the design, implementation and evaluation of personalised systems. It presents the different aspects that must be studied before the design is even started, and how to avoid pitfalls, in a hands-on approach. The chapter presents the main factors to take into account to design a recommender system, and illustrates them through case studies of existing systems to help navigate in the many and complex choices that have to be faced.
Bringing Students into a Discipline: Reflections on a Travel Study
ERIC Educational Resources Information Center
Chernega, Jennifer Nargang; Osgood, Aurea K.
2012-01-01
This commentary describes a two-week domestic travel study course for undergraduate sociology students designed to introduce students to the practice of social research and to the larger discipline of sociology. We arranged activities, presentations, and experiences in Chicago and Washington, DC. In this article, we outline the relevant parts of…
Picking a Hill to Die On: Discreet Activism, Leadership and Social Justice in Education
ERIC Educational Resources Information Center
Ryan, James; Tuters, Stephanie
2017-01-01
Purpose: The purpose of this paper is to describe a study that explores the discreet activist strategies of educational leaders who promote social justice. Design/methodology/approach: Part of a larger project, this study employed qualitative methods. In particular, researchers interviewed 26 leaders--principals, vice principals, department heads,…
Creative Leadership? "It's Just the Norm"
ERIC Educational Resources Information Center
Keamy, Ron
2016-01-01
Creativity in teaching and leadership continues to be a topic of interest in education. This article focuses on comments made by a school's leadership team as part of a larger study in which a mixed methods case study design involving the school's leadership team and staff who taught Arts (either as specialist teachers or generalist classroom…
Managing Information and Communication Technology in Sudanese Secondary School
ERIC Educational Resources Information Center
Ahmed, Abdelrahman
2015-01-01
This research article is based on a larger study whose purpose was to investigate the current status and implementation of ICT in Khartoum State secondary schools. The study, adopted a descriptive survey design. Two instruments questionnaires and a structured interview schedule were used to collect data. The target population comprised of 320…
Medicine Education for Schoolchildren: What Do the Teachers Think?
ERIC Educational Resources Information Center
Hameen-Anttila, Katri; Airaksinen, Marja; Timonen, Johanna; Bush, Patricia; Ahonen, Riitta
2006-01-01
Purpose: The aim of this study is to investigate teachers' attitudes towards medicines and to determine what they are willing to teach children about medicines. This study is part of a larger project where medicine education materials accessible on the internet (www.uku.filaakekasvatus, in Finnish with English introduction) were designed,…
Mixer-Ejector Wind Turbine: Breakthrough High Efficiency Shrouded Wind Turbine
DOE Office of Scientific and Technical Information (OSTI.GOV)
None
2010-02-22
Broad Funding Opportunity Announcement Project: FloDesign Wind Turbine’s innovative wind turbine, inspired by the design of jet engines, could deliver 300% more power than existing wind turbines of the same rotor diameter by extracting more energy over a larger area. FloDesign Wind Turbine’s unique shrouded design expands the wind capture area, and the mixing vortex downstream allows more energy to flow through the rotor without stalling the turbine. The unique rotor and shrouded design also provide significant opportunity for mass production and simplified assembly, enabling mid-scale turbines (approximately 100 kW) to produce power at a cost that is comparable tomore » larger-scale conventional turbines.« less
Valdez, Rupa Sheth; Brennan, Patricia Flatley
2015-05-01
There is a need to ensure that the growing number of consumer health information technologies designed to support patient engagement account for the larger social context in which health is managed. Basic research on how patients engage this larger social context is needed as a precursor to the development of patient-centered consumer health information technology (IT) solutions. The purpose of this study was to inform the broader design of consumer health IT by characterizing patients' existing health information communication practices with their social network members. This qualitative study took place between 2010 and 2012 in a Midwestern city. Eighteen patients with chronic conditions participated in a semi-structured interview that was analyzed using qualitative content analysis and descriptive statistics. Emphasis was placed on recruiting a sample representing diverse cultural groups and including participants of low socioeconomic status. Participants' social networks included a wide range of individuals, spanning biological relatives, divinities, and second-degree relationships. Participants' rationales for health information communication reflected seven themes: (1) characteristics and circumstances of the person, (2) characteristics and circumstances of the relationship, (3) structure and composition of the social network, (4) content of the message, (5) orientation of the goal, (6) dimensions of the context, and (7) adaptive practices. This study demonstrates that patients' health information communication practices are multidimensional, engaging individuals beyond formal and informal caregivers and driven by characteristics of their personal lives and larger social contexts in addition to their health problem. New models of consumer health IT must be created to better align with the realities of patients' communication routines. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
Dargel, Jens; Michael, Joern W P; Feiser, Janna; Ivo, Roland; Koebke, Juergen
2011-04-01
This study investigates differences in the anatomy of male and female knee joints to contribute to the current debate on sex-specific total knee implants. Morphometric data were obtained from 60 human cadaver knees, and sex differences were calculated. All data were corrected for height, and male and female specimens presenting with an identical length of the femur were analyzed as matched pairs. Male linear knee joint dimensions were significantly larger when compared with females. When corrected for differences in height, medial-lateral dimensions of male knees were significantly larger than female; however, matched paired analysis did not prove these differences to be consistent. Although implant design should focus interindividual variations in knee joint anatomy, our data do not support the concept of a female-specific implant design. Copyright © 2011 Elsevier Inc. All rights reserved.
Design and Verification of Blast Densification for Highway Embankments of Liquefiable Sands
DOT National Transportation Integrated Search
2012-10-26
As part of a larger effort to investigate the effects of blast densification on the properties and : behavior of compacted sand deposits, this study presents a procedure for replicating in the : laboratory the occluded gas bubbles believed to exist i...
Measure Twice, Build Once: Bench-Scale Testing to Evaluate Bioretention Media Design
The paper discusses the utility of conducting bench-scale testing on selected bioretention media and media amendments to validate hydrologic properties before installing media and amendments in larger pilot- or full-scale rain garden installations. The bench-scale study conclude...
From randomized controlled trials to observational studies.
Silverman, Stuart L
2009-02-01
Randomized controlled trials are considered the gold standard in the hierarchy of research designs for evaluating the efficacy and safety of a treatment intervention. However, their results can have limited applicability to patients in clinical settings. Observational studies using large health care databases can complement findings from randomized controlled trials by assessing treatment effectiveness in patients encountered in day-to-day clinical practice. Results from these designs can expand upon outcomes of randomized controlled trials because of the use of larger and more diverse patient populations with common comorbidities and longer follow-up periods. Furthermore, well-designed observational studies can identify clinically important differences among therapeutic options and provide data on long-term drug effectiveness and safety.
Structural Behavior of Concrete Beams Reinforced with Basalt Fiber Reinforced Polymer (BFRP) Bars
NASA Astrophysics Data System (ADS)
Ovitigala, Thilan
The main challenge for civil engineers is to provide sustainable, environmentally friendly and financially feasible structures to the society. Finding new materials such as fiber reinforced polymer (FRP) material that can fulfill the above requirements is a must. FRP material was expensive and it was limited to niche markets such as space shuttles and air industry in the 1960s. Over the time, it became cheaper and spread to other industries such as sporting goods in the 1980-1990, and then towards the infrastructure industry. Design and construction guidelines are available for carbon fiber reinforced polymer (CFRP), aramid fiber reinforced polymer (AFRP) and glass fiber reinforced polymer (GFRP) and they are currently used in structural applications. Since FRP is linear elastic brittle material, design guidelines for the steel reinforcement are not valid for FRP materials. Corrosion of steel reinforcement affects the durability of the concrete structures. FRP reinforcement is identified as an alternative to steel reinforcement in corrosive environments. Although basalt fiber reinforced polymer (BFRP) has many advantages over other FRP materials, but limited studies have been done. These studies didn't include larger BFRP bar diameters that are mostly used in practice. Therefore, larger beam sizes with larger BFRP reinforcement bar diameters are needed to investigate the flexural and shear behavior of BFRP reinforced concrete beams. Also, shear behavior of BFRP reinforced concrete beams was not yet studied. Experimental testing of mechanical properties and bond strength of BFRP bars and flexural and shear behavior of BFRP reinforced concrete beams are needed to include BFRP reinforcement bars in the design codes. This study mainly focuses on the use of BFRP bars as internal reinforcement. The test results of the mechanical properties of BFRP reinforcement bars, the bond strength of BFRP reinforcement bars, and the flexural and shear behavior of concrete beams reinforced with BFRP reinforcement bars are presented and verified with other research studies, existing design codes and guidelines provided for other FRP bars. Based on the experimental testing results, analytical equations were developed and existing equations were modified to predict the actual structural behavior of FRP bar reinforced concrete beams with reasonable accuracy.
Vision Test Validation Study for the Health Examination Survey Among Youths 12-17 years.
ERIC Educational Resources Information Center
Roberts, Jean
A validation study of the vision test battery used in the Health Examination Survey of 1966-1970 was conducted among 210 youths 12-17 years-old who had been part of the larger survey. The study was designed to discover the degree of correspondence between survey test results and clinical examination by an opthalmologist in determining the…
Tuffaha, Haitham W; Reynolds, Heather; Gordon, Louisa G; Rickard, Claire M; Scuffham, Paul A
2014-12-01
Value of information analysis has been proposed as an alternative to the standard hypothesis testing approach, which is based on type I and type II errors, in determining sample sizes for randomized clinical trials. However, in addition to sample size calculation, value of information analysis can optimize other aspects of research design such as possible comparator arms and alternative follow-up times, by considering trial designs that maximize the expected net benefit of research, which is the difference between the expected cost of the trial and the expected value of additional information. To apply value of information methods to the results of a pilot study on catheter securement devices to determine the optimal design of a future larger clinical trial. An economic evaluation was performed using data from a multi-arm randomized controlled pilot study comparing the efficacy of four types of catheter securement devices: standard polyurethane, tissue adhesive, bordered polyurethane and sutureless securement device. Probabilistic Monte Carlo simulation was used to characterize uncertainty surrounding the study results and to calculate the expected value of additional information. To guide the optimal future trial design, the expected costs and benefits of the alternative trial designs were estimated and compared. Analysis of the value of further information indicated that a randomized controlled trial on catheter securement devices is potentially worthwhile. Among the possible designs for the future trial, a four-arm study with 220 patients/arm would provide the highest expected net benefit corresponding to 130% return-on-investment. The initially considered design of 388 patients/arm, based on hypothesis testing calculations, would provide lower net benefit with return-on-investment of 79%. Cost-effectiveness and value of information analyses were based on the data from a single pilot trial which might affect the accuracy of our uncertainty estimation. Another limitation was that different follow-up durations for the larger trial were not evaluated. The value of information approach allows efficient trial design by maximizing the expected net benefit of additional research. This approach should be considered early in the design of randomized clinical trials. © The Author(s) 2014.
Mauz, Elvira; von der Lippe, Elena; Allen, Jennifer; Schilling, Ralph; Müters, Stephan; Hoebel, Jens; Schmich, Patrick; Wetzstein, Matthias; Kamtsiuris, Panagiotis; Lange, Cornelia
2018-01-01
Population-based surveys currently face the problem of decreasing response rates. Mixed-mode designs are now being implemented more often to account for this, to improve sample composition and to reduce overall costs. This study examines whether a concurrent or sequential mixed-mode design achieves better results on a number of indicators of survey quality. Data were obtained from a population-based health interview survey of adults in Germany that was conducted as a methodological pilot study as part of the German Health Update (GEDA). Participants were randomly allocated to one of two surveys; each of the surveys had a different design. In the concurrent mixed-mode design ( n = 617) two types of self-administered questionnaires (SAQ-Web and SAQ-Paper) and computer-assisted telephone interviewing were offered simultaneously to the respondents along with the invitation to participate. In the sequential mixed-mode design ( n = 561), SAQ-Web was initially provided, followed by SAQ-Paper, with an option for a telephone interview being sent out together with the reminders at a later date. Finally, this study compared the response rates, sample composition, health indicators, item non-response, the scope of fieldwork and the costs of both designs. No systematic differences were identified between the two mixed-mode designs in terms of response rates, the socio-demographic characteristics of the achieved samples, or the prevalence rates of the health indicators under study. The sequential design gained a higher rate of online respondents. Very few telephone interviews were conducted for either design. With regard to data quality, the sequential design (which had more online respondents) showed less item non-response. There were minor differences between the designs in terms of their costs. Postage and printing costs were lower in the concurrent design, but labour costs were lower in the sequential design. No differences in health indicators were found between the two designs. Modelling these results for higher response rates and larger net sample sizes indicated that the sequential design was more cost and time-effective. This study contributes to the research available on implementing mixed-mode designs as part of public health surveys. Our findings show that SAQ-Paper and SAQ-Web questionnaires can be combined effectively. Sequential mixed-mode designs with higher rates of online respondents may be of greater benefit to studies with larger net sample sizes than concurrent mixed-mode designs.
Swift, Judy Anne; Tischler, Victoria; Markham, Sophie; Gunning, Ingrid; Glazebrook, Cris; Beer, Charlotte; Puhl, Rebecca
2013-01-01
Background Weight bias is an important clinical issue that the educators of tomorrow's healthcare professionals cannot afford to ignore. This study, therefore, aimed to pilot a randomized controlled trial of the effects of educational films designed to reduce weight stigmatization toward obese patients on trainee dietitians’ and doctors’ attitudes. Methods A pre-post experimental design with a 6-week follow-up, which consisted of an intervention group (n = 22) and a control group (n = 21), was conducted to assess the efficacy of brief anti-stigma films in reducing weight bias, and to test whether future, larger-scale studies among trainee healthcare professionals are feasible. Results Participants at baseline demonstrated weight bias, on both implicit and explicit attitude measures, as well as strong beliefs that obesity is under a person's control. The intervention films significantly improved explicit attitudes and beliefs toward obese people, and participant evaluation was very positive. The intervention did not significantly improve implicit anti-fat bias. Conclusion The current study suggests both that it is possible to conduct a substantive trial of the effects of educational films designed to reduce weight stigma on a larger cohort of trainee healthcare professionals, and that brief educational interventions may be effective in reducing stigmatizing attitudes in this population. PMID:23466551
Swift, Judy Anne; Tischler, Victoria; Markham, Sophie; Gunning, Ingrid; Glazebrook, Cris; Beer, Charlotte; Puhl, Rebecca
2013-01-01
Weight bias is an important clinical issue that the educators of tomorrow's healthcare professionals cannot afford to ignore. This study, therefore, aimed to pilot a randomized controlled trial of the effects of educational films designed to reduce weight stigmatization toward obese patients on trainee dietitians' and doctors' attitudes. A pre-post experimental design with a 6-week follow-up, which consisted of an intervention group (n = 22) and a control group (n = 21), was conducted to assess the efficacy of brief anti-stigma films in reducing weight bias, and to test whether future, larger-scale studies among trainee healthcare professionals are feasible. Participants at baseline demonstrated weight bias, on both implicit and explicit attitude measures, as well as strong beliefs that obesity is under a person's control. The intervention films significantly improved explicit attitudes and beliefs toward obese people, and participant evaluation was very positive. The intervention did not significantly improve implicit anti-fat bias. The current study suggests both that it is possible to conduct a substantive trial of the effects of educational films designed to reduce weight stigma on a larger cohort of trainee healthcare professionals, and that brief educational interventions may be effective in reducing stigmatizing attitudes in this population.
Neighborhood Disorganization, Substance Use, and Violence among Adolescents in Puerto Rico
ERIC Educational Resources Information Center
Reyes, Juan C.; Robles, Rafaela R.; Colon, Hector M.; Negron, Juan; Matos, Tomas D.; Calderon, Jose; Perez, Olga M.
2008-01-01
This study investigates the role of neighborhoods in adolescent violence in poor neighborhoods in San Juan, Puerto Rico. The study is part of a larger longitudinal project examining risk and resilience in adolescents' ages 12 to 15 years old and their caregivers. Using a cross-sectional design, a self-completion questionnaire, and an interviewer…
Health Promotion in a Prison Setting: Experience in Villabona Prison
ERIC Educational Resources Information Center
Muro, Pilar; Enjuanes, Jordi; Morata, Txus; Palasí, Eva
2016-01-01
Aim: The aim of this study was to analyse experiences of a health promotion intervention implemented by the Therapeutic and Educational Unit at Villabona prison in Spain, which aimed to create drug-free spaces as part of a model of social rehabilitation. Design: As part of a larger participatory evaluation study concerning the efficacy of…
Attitudes of Early Adolescents toward Science, Women in Science, and Science Careers.
ERIC Educational Resources Information Center
Erb, Thomas Owen
The study described is part of a larger project, Career Oriented Modules to Explore Topics in Science (COMETS), designed to integrate career education into the science curriculum. This study aimed to determine the attitudes of male and female students aged 10-16 toward scientists, science, women in science, careers in technical fields, and careers…
ERIC Educational Resources Information Center
Amuko, Sheila; Miheso, Marguerite; Ndeuthi, Sophie
2015-01-01
This presentation is based on a larger study whose purpose was to explore the various opportunities and challenges influencing integration of ICT in teaching and learning Mathematics in secondary schools in Nairobi County. The study, adopted a descriptive survey design. Three instruments questionnaires', a structured interview schedule and an…
Information and Digital Literacies in a Kindergarten Classroom: An I-LEARN Case Study
ERIC Educational Resources Information Center
Tecce DeCarlo, Mary Jean; Grant, Allen; Lee, Vera J.; Neuman, Delia
2018-01-01
This case study, part of a larger qualitative research project, involved 24 kindergarteners and their teacher in the design, development, and evaluation of a research project built around the I-LEARN model (Neuman, "Learning in information-rich environments: I-LEARN and the construction of knowledge in the 21st Century." Springer, New…
Design of an adiabatic demagnetization refrigerator for studies in astrophysics
NASA Technical Reports Server (NTRS)
Castles, S.
1983-01-01
An adiabatic demagnetization refrigerator was designed for cooling infrared bolometers for studies in astrophysics and aeronomy. The design was tailored to the requirements of a Shuttle sortie experiment. The refrigerator should be capable of maintaining three bolometers at 0.1 K with a 90% cycle. The advantage are of operations the bolometer at 0.1K. greater sensitivity, faster response time, and the ability to use larger bolometer elements without compromising the response time. The design presented is the first complete design of an ADR intended for use in space. The most important of these specifications are to survive a Shuttle launch, to operate with 1.5 K - 2.0 K space-pumped liquid helium as a heat sink, to have a 90% duty cycle, and to be highly efficient.
Understanding the Lunar System Architecture Design Space
NASA Technical Reports Server (NTRS)
Arney, Dale C.; Wilhite, Alan W.; Reeves, David M.
2013-01-01
Based on the flexible path strategy and the desire of the international community, the lunar surface remains a destination for future human exploration. This paper explores options within the lunar system architecture design space, identifying performance requirements placed on the propulsive system that performs Earth departure within that architecture based on existing and/or near-term capabilities. The lander crew module and ascent stage propellant mass fraction are primary drivers for feasibility in multiple lander configurations. As the aggregation location moves further out of the lunar gravity well, the lunar lander is required to perform larger burns, increasing the sensitivity to these two factors. Adding an orbit transfer stage to a two-stage lunar lander and using a large storable stage for braking with a one-stage lunar lander enable higher aggregation locations than Low Lunar Orbit. Finally, while using larger vehicles enables a larger feasible design space, there are still feasible scenarios that use three launches of smaller vehicles.
NASA Technical Reports Server (NTRS)
Loane, J. T.; Bowhill, S. A.; Mayes, P. E.
1982-01-01
The effects of atmospheric turbulence and the basis for the coherent scatter radar techniques are discussed. The reasons are given for upgrading the Radar system to a larger steerable array. Phase array theory pertinent to the system design is reviewed, along with approximations for maximum directive gain and blind angles due to mutual coupling. The methods and construction techniques employed in the UHF model study are explained. The antenna range is described, with a block diagram for the mode of operation used.
Zeligman, Liran; Zivotofsky, Ari Z.
2017-01-01
The pro and anti-saccade task (PAT) is a widely used tool in the study of overt and covert attention with promising potential role in neurocognitive and psychiatric assessment. However, specific PAT protocols can vary significantly between labs, potentially resulting in large variations in findings across studies. In light of recent calls towards a standardization of PAT the current study's objective was to systematically and purposely evaluate the effects of block vs. interleaved administration—a fundamental consideration—on PAT measures in a within subject design. Additionally, this study evaluated whether measures of a Posner-type cueing paradigm parallels measures of the PAT paradigm. As hypothesized, results indicate that PAT performance is highly susceptible to administration mode. Interleaved mode resulted in larger error rates not only for anti (blocks: M = 22%; interleaved: M = 42%) but also for pro-saccades (blocks: M = 5%; interleaved: M = 12%). This difference between block and interleaved administration was significantly larger in anti-saccades compared to pro-saccades and cannot be attributed to a 'speed/accuracy tradeoff'. Interleaved mode produced larger pro and anti-saccade differences in error rates while block administration produced larger latency differences. Results question the reflexive nature of pro-saccades, suggesting they are not purely reflexive. These results were further discussed and compared to previous studies that included within subject data of blocks and interleaved trials. PMID:28222173
Conceptual design of a lunar oxygen pilot plant Lunar Base Systems Study (LBSS) task 4.2
NASA Technical Reports Server (NTRS)
1988-01-01
The primary objective was to develop conceptual designs of two pilot plants to produce oxygen from lunar materials. A lunar pilot plant will be used to generate engineering data necessary to support an optimum design of a larger scale production plant. Lunar oxygen would be of primary value as spacecraft propellant oxidizer. In addition, lunar oxygen would be useful for servicing nonregenerative fuel cell power systems, providing requirements for life support, and to make up oxygen losses from leakage and airlock cycling. Thirteen different lunar oxygen production methods are described. Hydrogen reduction of ilmenite and extraction of solar-wind hydrogen from bulk lunar soil were selected for conceptual design studies. Trades and sensitivity analyses were performed with these models.
2017-01-01
A large body of evidence supports the effectiveness of larger health warnings on cigarette packages. However, there is limited research examining attitudes toward such warning labels, which has potential implications for implementation of larger warning labels. The purpose of the current study was to examine attitudes toward larger warning sizes on cigarette packages and examine variables associated with more favorable attitudes. In a nationally representative survey of U.S. adults (N = 5,014), participants were randomized to different warning size conditions, assessing attitude toward “a health warning that covered (25, 50, 75) % of a cigarette pack.” SAS logistic regression survey procedures were used to account for the complex survey design and sampling weights. Across experimental groups, nearly three-quarters (72%) of adults had attitudes supportive of larger warning labels on cigarette packs. Among the full sample and smokers only (N = 1,511), most adults had favorable attitudes toward labels that covered 25% (78.2% and 75.2%, respectively), 50% (70% and 58.4%, respectively), and 75% (67.9% and 61%, respectively) of a cigarette pack. Young adults, females, racial/ethnic minorities, and non-smokers were more likely to have favorable attitudes toward larger warning sizes. Among smokers only, females and those with higher quit intentions held more favorable attitudes toward larger warning sizes. Widespread support exists for larger warning labels on cigarette packages among U.S. adults, including among smokers. Our findings support the implementation of larger health warnings on cigarette packs in the U.S. as required by the 2009 Tobacco Control Act. PMID:28253257
Hernández, Sergio Elías; Suero, José; Barros, Alfonso; González-Mora, José Luis; Rubia, Katya
2016-01-01
Objectives To investigate regional differences in grey matter volume associated with the practice of Sahaja Yoga Meditation. Design Twenty three experienced practitioners of Sahaja Yoga Meditation and twenty three non-meditators matched on age, gender and education level, were scanned using structural Magnetic Resonance Imaging and their grey matter volume were compared using Voxel-Based Morphometry. Results Grey matter volume was larger in meditators relative to non-meditators across the whole brain. In addition, grey matter volume was larger in several predominantly right hemispheric regions: in insula, ventromedial orbitofrontal cortex, inferior temporal and parietal cortices as well as in left ventrolateral prefrontal cortex and left insula. No areas with larger grey matter volume were found in non-meditators relative to meditators. Conclusions The study shows that long-term practice of Sahaja Yoga Meditation is associated with larger grey matter volume overall, and with regional enlargement in several right hemispheric cortical and subcortical brain regions that are associated with sustained attention, self-control, compassion and interoceptive perception. The increased grey matter volume in these attention and self-control mediating regions suggests use-dependent enlargement with regular practice of this meditation. PMID:26938433
The Three-Block Model of Universal Design for Learning Implementation in a High School
ERIC Educational Resources Information Center
Katz, Jennifer; Sugden, Ron
2013-01-01
The role of the school leader (principal) in supporting educational reform is explored through a case study of one high school implementing the Three Block Model of UDL (Katz, 2012a) in an effort to meet the needs of a diverse student population. This case study is a part of a much larger study exploring outcomes for students and teachers of…
Perceptions of Sexual Harassment in Athletic Training
ERIC Educational Resources Information Center
Shingles, René Revis; Smith, Yevonne
2008-01-01
Objective: To describe and analyze the experiences of ethnically diverse female certified athletic trainers (ATCs) in order to discern the perceived nature of sexual harassment in the athletic training profession. Design and Setting: Both quantitative and qualitative methods were used for a larger study; however, only the qualitative data are…
Technology Priorities and Preferences of Developmental Mathematics Instructors
ERIC Educational Resources Information Center
Zientek, Linda; Skidmore, Susan T.; Saxon, D. Patrick; Edmonson, Stacey
2015-01-01
With the omnipresence of technology in society came the inevitable integration into education. This manuscript provides results of a statewide survey of developmental mathematics instructors' technology preferences and priorities across all levels of developmental mathematics courses. The study was part of a larger project designed to explore the…
Inquiry-Based Instruction: Does School Environmental Context Matter?
ERIC Educational Resources Information Center
Pea, Celestine H.
2012-01-01
In a larger study on teachers' beliefs about science teaching, one component looks at how school environmental context factors influence inquiry-based science instruction. Research shows that three broad categories of school environmental factors (human, sociocultural, design) impact inquiry-based teaching in some way. A mixed-method, sequential,…
Research on Cleaning Up in San Diego.
ERIC Educational Resources Information Center
Middleman, Stanley
1983-01-01
Discusses the evolution of a set of research programs (dealing with the removal of liquid contaminants from surfaces) used to introduce graduate students to methods of design, evaluation, and modification within the context of a larger research program. Stresses the simultaneity and interaction of theoretical and experimental studies. (JM)
NASA Astrophysics Data System (ADS)
Meng, Long; Zhou, Tao; He, Yan-ping; Zhao, Yong-sheng; Liu, Ya-dong
2017-10-01
Tower, Spar platform and mooring system are designed in the project based on a given 6-MW wind turbine. Under wind-induced only, wave-induced only and combined wind and wave induced loads, dynamic response is analyzed for a 6-MW Spar-type floating offshore wind turbine (FOWT) under operating conditions and parked conditions respectively. Comparison with a platform-fixed system (land-based system) of a 6-MW wind turbine is carried out as well. Results demonstrate that the maximal out-of-plane deflection of the blade of a Spar-type system is 3.1% larger than that of a land-based system; the maximum response value of the nacelle acceleration is 215% larger for all the designed load cases being considered; the ultimate tower base fore-aft bending moment of the Spar-type system is 92% larger than that of the land-based system in all of the Design Load Cases (DLCs) being considered; the fluctuations of the mooring tension is mainly wave-induced, and the safety factor of the mooring tension is adequate for the 6-MW FOWT. The results can provide relevant modifications to the initial design for the Spar-type system, the detailed design and model basin test of the 6-MW Spar-type system.
Summary Article: IEA HPP Annex 36: Quality Installation / Quality Maintenance Sensitivity Studies
Hourahan, Glenn; Domanski, Piotr; Baxter, Van D.
2015-01-30
The outcome from this Annex activity clearly identifies that poorly designed, installed, and/or maintained heat pumps operate inefficiently and waste considerable energy compared to their as-designed potential. Additionally, it is clear that small faults for a given field-observed practice are significant, that some attribute deviations (in various equipment applications and geographical locations) have a larger impact than others, and that multiple faults or deviations have a cumulative impact on heat pump performance.
Influence of Reynolds Number on Multi-Objective Aerodynamic Design of a Wind Turbine Blade.
Ge, Mingwei; Fang, Le; Tian, De
2015-01-01
At present, the radius of wind turbine rotors ranges from several meters to one hundred meters, or even more, which extends Reynolds number of the airfoil profile from the order of 105 to 107. Taking the blade for 3MW wind turbines as an example, the influence of Reynolds number on the aerodynamic design of a wind turbine blade is studied. To make the study more general, two kinds of multi-objective optimization are involved: one is based on the maximum power coefficient (CPopt) and the ultimate load, and the other is based on the ultimate load and the annual energy production (AEP). It is found that under the same configuration, the optimal design has a larger CPopt or AEP (CPopt//AEP) for the same ultimate load, or a smaller load for the same CPopt//AEP at higher Reynolds number. At a certain tip-speed ratio or ultimate load, the blade operating at higher Reynolds number should have a larger chord length and twist angle for the maximum Cpopt//AEP. If a wind turbine blade is designed by using an airfoil database with a mismatched Reynolds number from the actual one, both the load and Cpopt//AEP will be incorrectly estimated to some extent. In some cases, the assessment error attributed to Reynolds number is quite significant, which may bring unexpected risks to the earnings and safety of a wind power project.
Religion and Wellbeing: Concurrent Validation of the Spiritual Well-Being Scale.
ERIC Educational Resources Information Center
Bufford, Rodger K.; Parker, Thomas G., Jr.
This study was designed to explore the concurrent validity of the Spiritual Well-being Scale (SWB). Ninety first-year student volunteers at an evangelical seminary served as subjects. As part of a larger study, the students completed the SWB and the Interpersonal Behavior Survey (IBS). The SWB Scale is a 20-item self-report scale. Ten items…
ERIC Educational Resources Information Center
Carbanaro, Michael; Dawber, Tess; Arav, Isanna
2006-01-01
The purpose of this study was to compare undergraduate nursing students' achievement on examinations for three groups in a mandatory microbiology course. The study represents one aspect of a larger research project designed to gain insight into factors that may influence online learning for distance education nursing students at a Canadian…
Experience with the lathe cut Bausch & Lomb SOFLENS: Part 1--Clinical study.
Weissman, B A; Levinson, A
1978-03-01
This study consists of clinical experience with the recently produced lathe cut Bausch & lomb SOFTLENS. Sixteen patients were fitted with the spin cast and then lathe cut lens. Visual acuities were better with the lathe cut lens. Comfort was good with both lenses. Some degree of circum-corneal injection was noted with the larger lathe cut design.
Factors Associated with Illegal Drug Use among Older Methadone Clients
ERIC Educational Resources Information Center
Rosen, Daniel
2004-01-01
Purpose. The overall aims of this study are to describe the life stressors of, exposure to illegal drug use of, and illegal drug use by older methadone clients. Design and Methods. The current study focuses on a sub-sample of the larger administrative data of a methadone clinic that is limited to African American and White clients over the age of…
ERIC Educational Resources Information Center
Barac, Karin; Prestige, Sarah; Main, Katherine
2017-01-01
This paper presents a summary of the key findings of a TPACK survey adapted for a higher education context and serves as an initial sampling technique for a larger study in the design and delivery practices of academics. There are few studies that investigate how technologies are used and experienced in courses from an objective pedagogical…
Learning from Team Teaching and Beyond: A Case Study on EFL Teachers' Professional Development
ERIC Educational Resources Information Center
Chen, Cheryl Wei-yu; Cheng, Yuh-show
2014-01-01
Framed in the sociocultural theory, this case study was designed to investigate teachers' professional growth as situated in team teaching and the larger teaching context. The participants were one pair of Taiwanese and foreign English teachers who were in their first year of practicing team teaching in an elementary school in Hsinchu City,…
The MANIFEST prototyping design study
NASA Astrophysics Data System (ADS)
Lawrence, Jonathan S.; Ben-Ami, Sagi; Brown, David M.; Brown, Rebecca A.; Case, Scott; Chapman, Steve; Churilov, Vladimir; Colless, Matthew; Content, Robert; Depoy, Darren; Evans, Ian; Farrell, Tony; Goodwin, Michael; Jacoby, George; Klauser, Urs; Kuehn, Kyler; Lorente, Nuria P. F.; Mali, Slavko; Marshall, Jennifer; Muller, Rolf; Nichani, Vijay; Pai, Naveen; Prochaska, Travis; Saunders, Will; Schmidt, Luke; Shortridge, Keith; Staszak, Nicholas F.; Szentgyorgyi, Andrew; Tims, Julia; Vuong, Minh V.; Waller, Lewis G.; Zhelem, Ross
2016-08-01
MANIFEST is a facility multi-object fibre system for the Giant Magellan Telescope, which uses `Starbug' fibre positioning robots. MANIFEST, when coupled to the telescope's planned seeing-limited instruments, GMACS, and G-CLEF, offers access to: larger fields of view; higher multiplex gains; versatile reformatting of the focal plane via IFUs; image-slicers; and in some cases higher spatial and spectral resolution. The Prototyping Design Study phase for MANIFEST, nearing completion, has focused on developing a working prototype of a Starbugs system, called TAIPAN, for the UK Schmidt Telescope, which will conduct a stellar and galaxy survey of the Southern sky. The Prototyping Design Study has also included work on the GMT instrument interfaces. In this paper, we outline the instrument design features of TAIPAN, highlight the modifications that will be necessary for the MANIFEST implementation, and provide an update on the MANIFEST/instrument interfaces.
Creating New Identities in Design Education
ERIC Educational Resources Information Center
Mendoza, Hannah Rose; Bernasconi, Claudia; MacDonald, Nora M.
2007-01-01
An international education opportunity has been created for design students at West Virginia University. This experience is unique because it takes an interdisciplinary approach to design that exposes students to the idea of a larger design methodology common to design professions. Students take core courses with students from a variety of design…
The effect of hospital unit layout on nurse walking behavior.
Yi, Lu; Seo, Hyun-Bo
2012-01-01
To confirm a new method for the research question, "How do different hospital unit layouts affect nurses' walking behavior and distance?" Concern is renewed regarding nurses' long walking distances because of the trend toward larger patient rooms with family areas inside, resulting in a larger overall unit size. Studies have found unit design characteristics that support nurses' efficient walking, but few have done it in units designed for patient- and family-centered care. To examine the effect of unit design on nurses' walking behavior, the authors propose a new method of observing a specific task. The authors observed nurses during the task of medication administration. Contrary to their hypotheses, results showed: (1) Experienced nurses had more unnecessary stops and longer walking distances than new nurses because of interactions; and (2) nurses in the smaller wing of the unit walked more than those in the larger wing of the same unit. The authors posit that the closeness between the nurses' path to the medication supply room and the central nurses' station affected the frequency of interactions and prompted a deviation from the shortest and most efficient path during medication administration. Observing a specific task to identify the effect of unit layout was effective, determining that overall unit shape or unit layout type might not be a good predictor of nurses' walking behavior; instead the characteristics of the path that connects functional spaces such as patient room and medication area might better predict nurses' walking behavior.
Optical design considerations when imaging the fundus with an adaptive optics correction
NASA Astrophysics Data System (ADS)
Wang, Weiwei; Campbell, Melanie C. W.; Kisilak, Marsha L.; Boyd, Shelley R.
2008-06-01
Adaptive Optics (AO) technology has been used in confocal scanning laser ophthalmoscopes (CSLO) which are analogous to confocal scanning laser microscopes (CSLM) with advantages of real-time imaging, increased image contrast, a resistance to image degradation by scattered light, and improved optical sectioning. With AO, the instrumenteye system can have low enough aberrations for the optical quality to be limited primarily by diffraction. Diffraction-limited, high resolution imaging would be beneficial in the understanding and early detection of eye diseases such as diabetic retinopathy. However, to maintain diffraction-limited imaging, sufficient pixel sampling over the field of view is required, resulting in the need for increased data acquisition rates for larger fields. Imaging over smaller fields may be a disadvantage with clinical subjects because of fixation instability and the need to examine larger areas of the retina. Reduction in field size also reduces the amount of light sampled per pixel, increasing photon noise. For these reasons, we considered an instrument design with a larger field of view. When choosing scanners to be used in an AOCSLO, the ideal frame rate should be above the flicker fusion rate for the human observer and would also allow user control of targets projected onto the retina. In our AOCSLO design, we have studied the tradeoffs between field size, frame rate and factors affecting resolution. We will outline optical approaches to overcome some of these tradeoffs and still allow detection of the earliest changes in the fundus in diabetic retinopathy.
By-Pass Diode Temperature Tests of a Solar Array Coupon under Space Thermal Environment Conditions
NASA Technical Reports Server (NTRS)
Wright, Kenneth H.; Schneider, Todd A.; Vaughn, Jason A.; Hoang, Bao; Wong, Frankie; Wu, Gordon
2016-01-01
By-Pass diodes are a key design feature of solar arrays and system design must be robust against local heating, especially with implementation of larger solar cells. By-Pass diode testing was performed to aid thermal model development for use in future array designs that utilize larger cell sizes that result in higher string currents. Testing was performed on a 56-cell Advanced Triple Junction solar array coupon provided by SSL. Test conditions were vacuum with cold array backside using discrete by-pass diode current steps of 0.25 A ranging from 0 A to 2.0 A.
Adhesive quality inspection of wind rotor blades using thermography
NASA Astrophysics Data System (ADS)
Li, Xiaoli; Sun, Jiangang; Shen, Jingling; Wang, Xun; Zhang, Cunlin; Zhao, Yuejin
2018-04-01
Wind power is playing an increasingly important role in ensuring electrical safety for human beings. Because wind rotor blades are getting larger and larger in order to harvest wind energy more efficiently, there is a growing demand for nondestructive testing. Due to the glue structure of rotor blades, adhesive quality evaluation is needed. In this study, three adhesive samples with a wall thickness of 13mm, 28mm or 31mm were each designed with a different adhesive situation. The transmission thermography was applied to inspect the samples. The results illustrate that this method is effective to inspect adhesive quality of wind rotor blades.
2017-05-12
through its employment of new technologies .4F5 But, how was Israel’s hitherto weakest service, with a history of embarrassment and failure, able to...able to destroy a much larger force with superior technology . It overcame a history of failure and decisively defeated an opponent with more resources...Design. The Israeli Navy, a small force with a bleak history , contributed to changing naval warfare forever during the battles of the Yom Kippur War
Armen, Roger S; Schiller, Stefan M; Brooks, Charles L
2010-06-01
Orthogonal aminoacyl-tRNA synthetase/tRNA pairs from archaea have been evolved to facilitate site specific in vivo incorporation of unnatural amino acids into proteins in Escherichia coli. Using this approach, unnatural amino acids have been successfully incorporated with high translational efficiency and fidelity. In this study, CHARMM-based molecular docking and free energy calculations were used to evaluate rational design of specific protein-ligand interactions for aminoacyl-tRNA synthetases. A series of novel unnatural amino acid ligands were docked into the p-benzoyl-L-phenylalanine tRNA synthetase, which revealed that the binding pocket of the enzyme does not provide sufficient space for significantly larger ligands. Specific binding site residues were mutated to alanine to create additional space to accommodate larger target ligands, and then mutations were introduced to improve binding free energy. This approach was used to redesign binding sites for several different target ligands, which were then tested against the standard 20 amino acids to verify target specificity. Only the synthetase designed to bind Man-alpha-O-Tyr was predicted to be sufficiently selective for the target ligand and also thermodynamically stable. Our study suggests that extensive redesign of the tRNA synthatase binding pocket for large bulky ligands may be quite thermodynamically unfavorable.
Spittal, Matthew J; Carlin, John B; Currier, Dianne; Downes, Marnie; English, Dallas R; Gordon, Ian; Pirkis, Jane; Gurrin, Lyle
2016-10-31
The Australian Longitudinal Study on Male Health (Ten to Men) used a complex sampling scheme to identify potential participants for the baseline survey. This raises important questions about when and how to adjust for the sampling design when analyzing data from the baseline survey. We describe the sampling scheme used in Ten to Men focusing on four important elements: stratification, multi-stage sampling, clustering and sample weights. We discuss how these elements fit together when using baseline data to estimate a population parameter (e.g., population mean or prevalence) or to estimate the association between an exposure and an outcome (e.g., an odds ratio). We illustrate this with examples using a continuous outcome (weight in kilograms) and a binary outcome (smoking status). Estimates of a population mean or disease prevalence using Ten to Men baseline data are influenced by the extent to which the sampling design is addressed in an analysis. Estimates of mean weight and smoking prevalence are larger in unweighted analyses than weighted analyses (e.g., mean = 83.9 kg vs. 81.4 kg; prevalence = 18.0 % vs. 16.7 %, for unweighted and weighted analyses respectively) and the standard error of the mean is 1.03 times larger in an analysis that acknowledges the hierarchical (clustered) structure of the data compared with one that does not. For smoking prevalence, the corresponding standard error is 1.07 times larger. Measures of association (mean group differences, odds ratios) are generally similar in unweighted or weighted analyses and whether or not adjustment is made for clustering. The extent to which the Ten to Men sampling design is accounted for in any analysis of the baseline data will depend on the research question. When the goals of the analysis are to estimate the prevalence of a disease or risk factor in the population or the magnitude of a population-level exposure-outcome association, our advice is to adopt an analysis that respects the sampling design.
Sample size determination for mediation analysis of longitudinal data.
Pan, Haitao; Liu, Suyu; Miao, Danmin; Yuan, Ying
2018-03-27
Sample size planning for longitudinal data is crucial when designing mediation studies because sufficient statistical power is not only required in grant applications and peer-reviewed publications, but is essential to reliable research results. However, sample size determination is not straightforward for mediation analysis of longitudinal design. To facilitate planning the sample size for longitudinal mediation studies with a multilevel mediation model, this article provides the sample size required to achieve 80% power by simulations under various sizes of the mediation effect, within-subject correlations and numbers of repeated measures. The sample size calculation is based on three commonly used mediation tests: Sobel's method, distribution of product method and the bootstrap method. Among the three methods of testing the mediation effects, Sobel's method required the largest sample size to achieve 80% power. Bootstrapping and the distribution of the product method performed similarly and were more powerful than Sobel's method, as reflected by the relatively smaller sample sizes. For all three methods, the sample size required to achieve 80% power depended on the value of the ICC (i.e., within-subject correlation). A larger value of ICC typically required a larger sample size to achieve 80% power. Simulation results also illustrated the advantage of the longitudinal study design. The sample size tables for most encountered scenarios in practice have also been published for convenient use. Extensive simulations study showed that the distribution of the product method and bootstrapping method have superior performance to the Sobel's method, but the product method was recommended to use in practice in terms of less computation time load compared to the bootstrapping method. A R package has been developed for the product method of sample size determination in mediation longitudinal study design.
Effects of respirator use on worker performance
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cardarelli, R.
1995-03-01
In 1993, EPRI funded Yankee Atomic Electric Company to examine the effects of respirator use on worker efficiency. Phase I of Yankee`s effort was to develop a study design to determine respirator effects. Given success in Phase I, a larger population will be tested to determine if a stasitically significant respirator effect on performance can be measured. This paper summarizes the 1993 EPRI/Yankee Respirator Effects of Pilot Study, and describes the study design for the 1994 EPRI/Yankee Respirator Study to be conducted at the Oyster Creek Nuclear Power Plant. Also described is a summary of respirator effect studies that havemore » been conducted during the last ten (10) years.« less
Professional Development and TransLink[R]. Final Report.
ERIC Educational Resources Information Center
Kuhn, Beverly T.; Jasek, Deborah
This report covers one segment of a larger professional development program for transportation professionals that addresses the need to develop a larger cadre of transportation professionals capable of designing, planning, managing, operating, and maintaining the transportation infrastructure nationwide. Three specific tasks were undertaken and…
Schiro, Jessica; Marcilly, Romaric; Leroy, Nicolas; Wawrzyniak, Clément; Martinot, Alain; Pelayo, Sylvia
2015-01-01
The study aims to identify the information useful to support a patients' EDs' choice in order to design a patient Web-based system. For that purpose, a focus group and a formative user test have been performed. The results show that five types of information can be relevant. The spontaneous favored information is the "distance" to EDs. The "Wait time", that is sanctified in literature, is only used in a second time. A larger summative evaluation should be planned to evaluate and validate the befits of this kind of tool.
Alexander, Paul E; Bonner, Ashley J; Agarwal, Arnav; Li, Shelly-Anne; Hariharan, Abishek; Izhar, Zain; Bhatnagar, Neera; Alba, Carolina; Akl, Elie A; Fei, Yutong; Guyatt, Gordon H; Beyene, Joseph
2016-06-01
Prior studies regarding whether single-center trial estimates are larger than multi-center are equivocal. We examined the extent to which single-center trials yield systematically larger effects than multi-center trials. We searched the 119 core clinical journals and the Cochrane Database of Systematic Reviews for meta-analyses (MAs) of randomized controlled trials (RCTs) published during 2012. In this meta-epidemiologic study, for binary variables, we computed the pooled ratio of ORs (RORs), and for continuous outcomes mean difference in standardized mean differences (SMDs), we conducted weighted random-effects meta-regression and random-effects MA modeling. Our primary analyses were restricted to MAs that included at least five RCTs and in which at least 25% of the studies used each of single trial center (SC) and more trial center (MC) designs. We identified 81 MAs for the odds ratio (OR) and 43 for the SMD outcome measures. Based on our analytic plan, our primary analysis (core) is based on 25 MAs/241 RCTs (binary outcome) and 18 MAs/173 RCTs (continuous outcome). Based on the core analysis, we found no difference in magnitude of effect between SC and MC for binary outcomes [RORs: 1.02; 95% confidence interval (CI): 0.83, 1.24; I(2) 20.2%]. Effect sizes were systematically larger for SC than MC for the continuous outcome measure (mean difference in SMDs: -0.13; 95% CI: -0.21, -0.05; I(2) 0%). Our results do not support prior findings of larger effects in SC than MC trials addressing binary outcomes but show a very similar small increase in effect in SC than MC trials addressing continuous outcomes. Authors of systematic reviews would be wise to include all trials irrespective of SC vs. MC design and address SC vs. MC status as a possible explanation of heterogeneity (and consider sensitivity analyses). Copyright © 2015 Elsevier Inc. All rights reserved.
Campus Ecology: A Guide to Assessing Environmental Quality and Creating Strategies for Change.
ERIC Educational Resources Information Center
Smith, April A.; And Others
This book is designed to take the environmental issues and principles currently being studied in the classroom and move them outside the classroom doors into the campus community and the larger world. By making environmental knowledge part and parcel of campus environmental practice, students, faculty, and administrators have an extraordinary…
Sexual Harassment in a Residential Occupation: The Experiences of Women Seafarers
ERIC Educational Resources Information Center
Thomas, Michelle A
2006-01-01
Objective: This paper reports women seafarers' experiences of sexual harassment. Design: Data reported in this paper were collected as part of a larger study exploring company policies and practices relating to women seafarers and the experiences of women seafarers themselves. Setting: Data reported here was collected with women from seven…
Designing a Virtual Grand Tour
ERIC Educational Resources Information Center
Hansen, Per Skafte
2004-01-01
The Virtual Grand Tour (VGT) is a paradigm for integrating a presentation of an overview of a larger subject with the possibility of launching at any time an exploratory study of a given sub-topic. The name derives from the paradigm's emulation of those 18th-century travels intended to educate (especially) young, affluent British men; today, with…
How Sociological Leaders Teach: Some Key Principles
ERIC Educational Resources Information Center
Persell, Caroline Hodges; Pfeiffer, Kathryn M.; Syed, Ali
2008-01-01
This paper arose from a larger study designed to explore what leaders in the field of sociology think are the most important goals and principles for students to understand after taking a college-level introductory course and how they teach those principles. A population of scholarly leaders in sociology was defined by various forms of peer…
Teaching about Consumption: The "Not Buying It" Project
ERIC Educational Resources Information Center
Grauerholz, Liz; Bubriski-McKenzie, Anne
2012-01-01
This study presents an experiential exercise designed to heighten students' awareness of overconsumption in the United States and allow them to see how their own consumption habits are linked to larger social factors. Students engaged in the "Not Buying It" project--which involved refraining from purchasing all but essentials for a set…
Gender and Evolutionary Theory in Workplace Health Promotion
ERIC Educational Resources Information Center
Björklund, Erika; Wright, Jan
2017-01-01
Objective: Ideas from evolutionary theories are increasingly taken up in health promotion. This article seeks to demonstrate how such a trend has the potential to embed essentialist and limiting stereotypes of women and men in health promotion practice. Design: We draw on material gathered for a larger ethnographic study that examined how…
Feasibility of an Online Professional Development Program for Early Intervention Practitioners
ERIC Educational Resources Information Center
Kyzar, Kathleen B.; Chiu, Caya; Kemp, Peggy; Aldersey, Heather Michelle; Turnbull, Ann P.; Lindeman, David P.
2014-01-01
This article reports findings from 2 studies situated within a larger scope of design research on a professional development program, "Early Years," for Part C early intervention practitioners, working with families in home and community settings. Early Years includes online modules and onsite mentor coaching, and its development has…
Digital London: Creating a Searchable Web of Interlinked Sources on Eighteenth Century London
ERIC Educational Resources Information Center
Shoemaker, Robert
2005-01-01
Purpose: To outline the conceptual and technical difficulties encountered, as well as the opportunities created, when developing an interlinked collection of web-based digitised primary sources on eighteenth century London. Design/methodology/approach: As a pilot study for a larger project, a variety of primary sources, including the "Old…
Communication, Academic, and Social Skills of Young Adults with Hearing Loss
ERIC Educational Resources Information Center
Eriks-Brophy, Alice; Durieux-Smith, Andree; Olds, Janet; Fitzpatrick, Elizabeth M.; Duquette, Cheryll; Whittingham, JoAnne
2012-01-01
This manuscript reports on data collected as part of a larger research study designed to investigate factors that facilitate the integration of children with hearing loss into mainstream environments. Aspects of communicative, academic, and social functioning for 43 adolescents and young adults were examined using questionnaires. In addition,…
Principals' Leadership Behaviors in Gang-Impacted High Schools and Their Effects on Pupil Climate.
ERIC Educational Resources Information Center
Schwartz, Audrey J.
Although viable leadership models for schools with differing social contexts are in great demand, empirical studies of high school principals have not produced consistent results. This paper summarizes part of a larger project designed to identify leadership behaviors of principals in "gang-impacted" and other secondary schools. The…
Discover Presidential Log Cabins. Teacher's Discussion Guide.
ERIC Educational Resources Information Center
National Park Service (Dept. of Interior), Washington, DC.
Discover Presidential Log Cabins is a set of materials designed to help educate 6-8 grade students about the significance of three log cabin sites occupied by George Washington, Ulysses Grant, Abraham Lincoln, and Theodore Roosevelt. This teacher's discussion guide is intended for use as part of a larger, comprehensive social studies program, and…
Reilly, Carolyn Miller; Higgins, Melinda; Smith, Andrew; Culler, Steven D; Dunbar, Sandra B
2015-11-01
This paper presents a secondary in-depth analysis of five persons with heart failure randomized to receive an education and behavioral intervention on fluid restriction as part of a larger study. Using a single subject analysis design, time series analyses models were constructed for each of the five patients for a period of 180 days to determine correlations between daily measures of patient reported fluid intake, thoracic impedance, and weights, and relationships between patient reported outcomes of symptom burden and health related quality of life over time. Negative relationships were observed between fluid intake and thoracic impedance, and between impedance and weight, while positive correlations were observed between daily fluid intake and weight. By constructing time series analyses of daily measures of fluid congestion, trends and patterns of fluid congestion emerged which could be used to guide individualized patient care or future research endeavors. Employment of such a specialized analysis technique allows for the elucidation of clinically relevant findings potentially disguised when only evaluating aggregate outcomes of larger studies. Copyright © 2015 Elsevier Inc. All rights reserved.
Design and implementation of a twin-family database for behavior genetics and genomics studies.
Boomsma, Dorret I; Willemsen, Gonneke; Vink, Jacqueline M; Bartels, Meike; Groot, Paul; Hottenga, Jouke Jan; van Beijsterveldt, C E M Toos; Stroet, Therese; van Dijk, Rob; Wertheim, Rien; Visser, Marco; van der Kleij, Frank
2008-06-01
In this article we describe the design and implementation of a database for extended twin families. The database does not focus on probands or on index twins, as this approach becomes problematic when larger multigenerational families are included, when more than one set of multiples is present within a family, or when families turn out to be part of a larger pedigree. Instead, we present an alternative approach that uses a highly flexible notion of persons and relations. The relations among the subjects in the database have a one-to-many structure, are user-definable and extendible and support arbitrarily complicated pedigrees. Some additional characteristics of the database are highlighted, such as the storage of historical data, predefined expressions for advanced queries, output facilities for individuals and relations among individuals and an easy-to-use multi-step wizard for contacting participants. This solution presents a flexible approach to accommodate pedigrees of arbitrary size, multiple biological and nonbiological relationships among participants and dynamic changes in these relations that occur over time, which can be implemented for any type of multigenerational family study.
The Minicommunity Design to Assess Indirect Effects of Vaccination.
Halloran, M Elizabeth
2012-08-01
We propose the minicommunity design to estimate indirect effects of vaccination. Establishing indirect effects of vaccination in unvaccinated subpopulations could have important implications for global vaccine policies. In the minicommunity design, the household or other small transmission unit serves as the cluster in which to estimate indirect effects of vaccination, similar to studies in larger communities to estimate indirect, total, and overall effects. Examples from the literature include studies in small transmission units to estimate indirect effects of pertussis, pneumococcal, influenza, and cholera vaccines. We characterize the minicommunity design by several methodologic considerations, including the assignment mechanism, ascertainment, the role of transmission outside the transmission unit, and the relation of the size of the transmission unit to number of people vaccinated. The minicommunity study for indirect effects is contrasted with studies to estimate vaccine effects on infectiousness and protective effects under conditions of household exposure within small transmission units. The minicommunity design can be easily implemented in individually randomized studies by enrolling and following-up members of households of the randomized individuals. The methodology for the minicommunity design for estimating indirect effects of vaccination deserves much future research.
Grmaš, Jernej; Stare, Katarina; Božič, Dane; Injac, Rade; Dreu, Rok
2017-08-01
The aim of this work is to use an experimental design approach to identify and study influential formulation and delivery device properties, which can be controlled by final product manufacturer, to establish design space, within which desired in vitro performance can be reached. Combining three factors, viscosity of suspension, nozzle orifice diameter (OD), and shot weight (SW), at three levels resulted in D-optimal experimental design with 20 runs. Responses within this study were droplet size distribution (DSD) and spray pattern (SP) in vitro tests. In addition, the amount of mechanical work needed for actuation was integrated from force profiles and used as a response. Results were fit to quadratic model by regression, which allowed also for determination of second-order and interaction effects between factors. Models were further optimized by keeping significant terms only. Optimized models were used to create response surfaces and design space with confidence levels. Viscosity has a dominant effect on DSD and modest effect on SP, with lower viscosities related to generation of smaller DSD and larger SP. Orifice diameter was found to have the highest impact on SP, with larger diameter resulting in larger SP. This effect was additionally confirmed by results of Plume Geometry in vitro test. Shot weight factor exerts significant influence on all tested metrics. Work, however, did not vary greatly with suspension viscosity or orifice diameter. Shot weight is the most dominant factor for work and important for DSD having a positive effect on both responses. In the case of SP, its relationship with shot weight is described by second-order polynomial fit. Inspection of raw data revealed that density of droplets within SP area is different for different shot weights. Presented study elucidated an inherent relationship between factors and responses and established mathematical models (response surfaces) for predictive purposes to target specific in vitro performance of nasal sprays by appropriate specification of factors, taking into account control space with included risk and uncertainty analysis.
The Crusades and Islam. Fulbright-Hays Summer Seminars Abroad, 1998 (Israel and Jordan).
ERIC Educational Resources Information Center
Serota, Laurie
These two mini-units are designed to supplement the areas of study dictated by the Core Knowledge Sequence, a content-rich curriculum used in the educator/curriculum developer's school. The mini-units fall in the middle of a 6-month-long study of the Middle Ages and incorporate the depth of content required to support the larger unit on the Middle…
ERIC Educational Resources Information Center
Juntunen, M. K.; Aksela, M. K.
2014-01-01
The aim of the study discussed in this paper was to link existing research about the argumentation skills of students to the teaching of life-cycle analysis (LCA) in order to promote an evidence-based approach to the teaching of and learning about materials used in consumer products. This case-study is part of a larger design research project that…
ERIC Educational Resources Information Center
Keesling, J. Ward; And Others
This study (one portion of a larger study) was designed to determine whether Elementary and Secondary Education Act Title I programs in State institutions for neglected or delinquent youth are effective in improving students' basic skills and attitudes and to determine which components of educational programs and characteristics of institutions…
ERIC Educational Resources Information Center
Bettinger, Eric; Doss, Christopher; Loeb, Susanna; Taylor, Eric
2015-01-01
Class size is a first-order consideration in the study of education production and education costs. How larger or smaller classes affect student outcomes is especially relevant to the growth and design of online classes. We study a field experiment in which college students were quasi-randomly assigned to either a large or a small class. All…
Effects of an Introductory Letter on Response Rates to a Teen/Parent Telephone Health Survey
ERIC Educational Resources Information Center
Woodruff, Susan I.; Mayer, Joni A.; Clapp, Elizabeth
2006-01-01
The authors conducted a pilot study in preparation for a larger investigation that will rely on telephone surveys to assess select health behaviors of teens and their parents, with a focus on indoor tanning. This study used a randomized design to assess the impact of a presurvey letter on response rates to a telephone survey, as well as prevalence…
Interior moisture design loads for residences
Anton TenWolde; Iain S. Walker
2001-01-01
This paper outlines a methodology to obtain design values for indoor boundary conditions for moisture design calculations for residences. This is part of a larger effort by ASHRAE Standard Project Committee 160P, Design Criteria for Moisture Control in Buildings, to formulate criteria for moisture design loads, analysis techniques, and material and building performance...
Underwater laser weld bowing distortion behavior and mechanism of thin 304 stainless steel plates
NASA Astrophysics Data System (ADS)
Huang, ZunYue; Luo, Zhen; Ao, Sansan; Cai, YangChuan
2018-10-01
Underwater laser weld bowing distortion behavior and mechanism of thin 304 stainless steel plates are studied in the paper. The influence of underwater laser welding parameters (such as laser power, welding speed, defocusing distance and gas flow rate) on weld bowing distortion was investigated through central composite rotatable design and an orthogonal test. A quadratic response model was established to evaluate the underwater laser weld bowing distortion by central composite rotatable design and the order of the impacts of the welding parameters on weld bowing distortion was studied by an orthogonal test. The weld bowing distortion after welding was determined by the digital image correlation technique. The weld bowing distortion of in-air laser welding and underwater laser welding were compared and it revealed that the shape of the in-air and underwater laser welded specimens are the same, but the weld bowing distortion amount of in-air welding is larger than that of underwater welding. Weld bowing distortion mechanism was studied by the digital image correlation technique, and it was demonstrated that weld bowing distortion is associated with the welding plate temperature gradient during laser welding. The wider weld width also resulted in larger weld bowing distortion.
Saxe, H; Kerstiens, G
2005-07-01
This study identifies the important role of climate change and photosynthetic photon flux density (PPFD) in the regenerative competence of ash and beech seedlings in 12 inter- and intra-specific competition designs in simulated mixed ash-beech forest gaps under conditions of non-limiting soil volume, water and nutrient supply. The growth conditions simulated natural forest conditions as closely as possible. Simulations were performed by growing interacting seedling canopies for one season in temperature-regulated closed-top chambers (CTCs). Eight CTCs were used in a factorial design with replicate treatments of [CO2] x temperature x PPFD x competition design. [CO2] tracked ambient levels or was 360 micromol mol-1 higher. Temperature tracked ambient levels or was 2.8 degrees C higher. PPFD on two plant tables inside each CTC was 16% and 5% of open-field levels, respectively, representative of typical light flux levels in a natural forest gap. In several of the competition designs, climate change made the ash seedlings grow taller than the beech seedlings and, at the same time, attain a larger leaf area and a larger total biomass. Advantages of this type for ash were found particularly at lower PPFD. There was a positive synergistic interaction of elevated temperature x [CO2] for both species, but more so for ash. There are many uncertainties when a study of chambered seedlings is to be projected to real changes in natural forests. Nevertheless, this study supports a possible future shift towards ash in north European, unmanaged, mixed ash-beech forests in response to the predicted climate change.
Cömert, Alper; Hyttinen, Jari
2015-05-15
With advances in technology and increasing demand, wearable biosignal monitoring is developing and new applications are emerging. One of the main challenges facing the widespread use of wearable monitoring systems is the motion artifact. The sources of the motion artifact lie in the skin-electrode interface. Reducing the motion and deformation at this interface should have positive effects on signal quality. In this study, we aim to investigate whether the structure supporting the electrode can be designed to reduce the motion artifact with the hypothesis that this can be achieved by stabilizing the skin deformations around the electrode. We compare four textile electrodes with different support structure designs: a soft padding larger than the electrode area, a soft padding larger than the electrode area with a novel skin deformation restricting design, a soft padding the same size as the electrode area, and a rigid support the same size as the electrode. With five subjects and two electrode locations placed over different kinds of tissue at various mounting forces, we simultaneously measured the motion artifact, a motion affected ECG, and the real-time skin-electrode impedance during the application of controlled motion to the electrodes. The design of the electrode support structure has an effect on the generated motion artifact; good design with a skin stabilizing structure makes the electrodes physically more motion artifact resilient, directly affecting signal quality. Increasing the applied mounting force shows a positive effect up to 1,000 gr applied force. The properties of tissue under the electrode are an important factor in the generation of the motion artifact and the functioning of the electrodes. The relationship of motion artifact amplitude to the electrode movement magnitude is seen to be linear for smaller movements. For larger movements, the increase of motion generated a disproportionally larger artifact. The motion artifact and the induced impedance change were caused by the electrode motion and contained the same frequency components as the applied electrode motion pattern. We found that stabilizing the skin around the electrode using an electrode structure that manages to successfully distribute the force and movement to an area beyond the borders of the electrical contact area reduces the motion artifact when compared to structures that are the same size as the electrode area.
ERIC Educational Resources Information Center
Daugherty, Michael K.; Carter, Vinson
2011-01-01
Design and drafting are subjects long taught in technology education, and subjects that retain high status in the profession. Admittedly, since the initial publication of Standards for Technological Literacy in 2000, design has taken on a larger role and meaning in the technology education profession. However, design continues to be delivered…
Influence of Reynolds Number on Multi-Objective Aerodynamic Design of a Wind Turbine Blade
Ge, Mingwei; Fang, Le; Tian, De
2015-01-01
At present, the radius of wind turbine rotors ranges from several meters to one hundred meters, or even more, which extends Reynolds number of the airfoil profile from the order of 105 to 107. Taking the blade for 3MW wind turbines as an example, the influence of Reynolds number on the aerodynamic design of a wind turbine blade is studied. To make the study more general, two kinds of multi-objective optimization are involved: one is based on the maximum power coefficient (C Popt) and the ultimate load, and the other is based on the ultimate load and the annual energy production (AEP). It is found that under the same configuration, the optimal design has a larger C Popt or AEP (C Popt//AEP) for the same ultimate load, or a smaller load for the same C Popt//AEP at higher Reynolds number. At a certain tip-speed ratio or ultimate load, the blade operating at higher Reynolds number should have a larger chord length and twist angle for the maximum C popt//AEP. If a wind turbine blade is designed by using an airfoil database with a mismatched Reynolds number from the actual one, both the load and C popt//AEP will be incorrectly estimated to some extent. In some cases, the assessment error attributed to Reynolds number is quite significant, which may bring unexpected risks to the earnings and safety of a wind power project. PMID:26528815
HFE and Spherical Cryostats MC Study
DOE Office of Scientific and Technical Information (OSTI.GOV)
Brodsky, Jason P.
2016-09-26
The copper vessel containing the nEXO TPC is surrounded by a buffer of HFE, a liquid refrigerant with very low levels of radioactive element contamination. The HFE is contained within the cryostat’s inner vessel, which is in turn inside the outer vessel. While some HFE may be necessary for stable cooling of nEXO, it is possible that using substantially more than necessary for thermal reasons will help reduce backgrounds originating in the cryostats. Using a larger amount of HFE is accomplished by making the cryostat vessels larger. By itself, increasing the cryostat size somewhat increases the background rate, as themore » thickness of the cryostat wall must increase at larger sizes. However, the additional space inside the cryostat will be filled with HFE which can absorb gamma rays headed for the TPC. As a result, increasing the HFE reduces the number of backgrounds reaching the TPC. The aim of this study was to determine the relationship between HFE thickness and background rate. Ultimately, this work should support choosing a cryostat and HFE size that satisfies nEXO’s background budget. I have attempted to account for every consequence of changing the cryostat size, although naturally this remains a work in progress until a final design is achieved. At the moment, the scope of the study includes only the spherical cryostat design. This study concludes that increasing cryostat size reduces backgrounds, reaching neglible backgrounds originating from the cryostat at the largest sizes. It also shows that backgrounds originating from the inherent radioactivity of the HFE plateau quickly, so may be considered essentially fixed at any quantity of HFE.« less
Micro-drinking behaviours and consumption of wine in different wine glass sizes: a laboratory study.
Zupan, Z; Pechey, R; Couturier, D L; Hollands, G J; Marteau, T M
2017-06-12
Tableware size may influence how much food and non-alcoholic drink is consumed. Preliminary evidence of the impact of glass size on purchasing of alcoholic drinks shows an increase in wine sales of almost 10% when the same portion of wine is served in a larger glass. The primary aim of the current study is to test if micro-drinking behaviours act as a mechanism that could underlie this effect, through an increase in drinking rate, sip duration and/or number of sips from a larger glass. In a between-subjects experimental design, 166 young women were randomised to drink a 175 ml portion of wine from either a smaller (250 ml) or larger (370 ml) wine glass. Primary outcomes were three micro-drinking behaviours, assessed observationally using video recordings: drinking rate, sip number and sip duration. Other possible mechanisms examined were satisfaction with the perceived amount of wine served and pleasure of the drinking experience, assessed using self-report measures. Wine drunk from the larger, compared with the smaller glass, was consumed more slowly and with shorter sip duration, counter to the hypothesised direction of effect. No differences were observed in any of the other outcome measures. These findings provide no support for the hypothesised mechanisms by which serving wine in larger wine glasses increases consumption. While micro-drinking behaviours may still prove to be a mechanism explaining consumption from different glass sizes, cross-validation of these results in a more naturalistic setting is needed.
Conceptual design and analysis of a dynamic scale model of the Space Station Freedom
NASA Technical Reports Server (NTRS)
Davis, D. A.; Gronet, M. J.; Tan, M. K.; Thorne, J.
1994-01-01
This report documents the conceptual design study performed to evaluate design options for a subscale dynamic test model which could be used to investigate the expected on-orbit structural dynamic characteristics of the Space Station Freedom early build configurations. The baseline option was a 'near-replica' model of the SSF SC-7 pre-integrated truss configuration. The approach used to develop conceptual design options involved three sets of studies: evaluation of the full-scale design and analysis databases, conducting scale factor trade studies, and performing design sensitivity studies. The scale factor trade study was conducted to develop a fundamental understanding of the key scaling parameters that drive design, performance and cost of a SSF dynamic scale model. Four scale model options were estimated: 1/4, 1/5, 1/7, and 1/10 scale. Prototype hardware was fabricated to assess producibility issues. Based on the results of the study, a 1/4-scale size is recommended based on the increased model fidelity associated with a larger scale factor. A design sensitivity study was performed to identify critical hardware component properties that drive dynamic performance. A total of 118 component properties were identified which require high-fidelity replication. Lower fidelity dynamic similarity scaling can be used for non-critical components.
Multi-fuel rotary engine for general aviation aircraft
NASA Technical Reports Server (NTRS)
Jones, C.; Ellis, D. R.; Meng, P. R.
1983-01-01
Design studies of advanced multifuel general aviation and commuter aircraft rotary stratified charge engines are summarized. Conceptual design studies were performed at two levels of technology, on advanced general aviation engines sized to provide 186/250 shaft kW/hp under cruise conditions at 7620 (25000 m/ft) altitude. A follow on study extended the results to larger (2500 hp max.) engine sizes suitable for applications such as commuter transports and helicopters. The study engine designs were derived from relevant engine development background including both prior and recent engine test results using direct injected unthrottled rotary engine technology. Aircraft studies, using these resultant growth engines, define anticipated system effects of the performance and power density improvements for both single engine and twin engine airplanes. The calculated results indicate superior system performance and 27 to 33 percent fuel economy improvement for the rotary engine airplanes as compared to equivalent airframe concept designs with current baseline engines. The research and technology activities required to attain the projected engine performance levels are also discussed.
DOT National Transportation Integrated Search
2014-06-01
The introduction of larger aircrafts on flexible airfield pavements has led to a need for asphalt mixtures capable of sustaining such heavy : loads. This laboratory and analytical study investigated the mechanical responses of a number of modified as...
Communication Skills for OMRDD Direct Care Workers Distance Learning Program. Video Guide.
ERIC Educational Resources Information Center
Denny, Verna Haskins
Adapted from a larger distance learning program, this video guide is designed for use by students who feel most comfortable working within the video modality. It contains self-study exercises for development of job-related reading, writing, problem-solving, and reasoning skills required of direct care workers. This independent, self-paced course…
Mirroring Ourselves: Teacher Educators of Color Reading Multicultural Texts
ERIC Educational Resources Information Center
Suh, Yonghee; Hinton, KaaVonia
2015-01-01
During the last few decades, U.S. classrooms have experienced dramatic demographic changes. This article is based on the results of a larger self-study in which four teacher educators of color participated in a book club designed to discuss the pedagogical possibilities of Yoko Kawashima Watkins' "So Far from the Bamboo Grove" (1986) and…
Students of "Easy" Languages: Their Beliefs about Language Learning.
ERIC Educational Resources Information Center
Kuntz, Patricia S.
This paper investigates the beliefs about language learning held by 53 first-month university students enrolled in Swahili compared to those of 113 students of French and Spanish. Based in part upon the research design and instrument of Elaine Horwitz (University of Texas-Austin), this paper isolates the results from a larger study of eight…
ERIC Educational Resources Information Center
Van Offelen, Sara; Sherman, Shelley; May, Jill; Rhodes, Felisha
2011-01-01
A focus group of Somali immigrants was conducted as part of a larger study of underserved communities in Minnesota. The goal was to capture Somali women's personal experiences and views on nutrition. This understanding assists Health and Nutrition educators in assessing the quality and effectiveness of current programming efforts and making…
ERIC Educational Resources Information Center
Glazerman, Steven; Protik, Ali; Teh, Bing-ru; Bruch, Julie; Seftor, Neil
2012-01-01
This report describes the implementation and intermediate impacts of an intervention designed to provide incentives for a school district's highest-performing teachers to work in its lowest-achieving schools. The report is part of a larger study in which random assignment was used to form two equivalent groups of classrooms organized into teacher…
The Supply of Information Technology Workers in the United States.
ERIC Educational Resources Information Center
Freeman, Peter; Aspray, William
This study is designed to improve understanding of the supply of and demand for information technology (IT) workers in America and contextual issues surrounding that topic. Chapter 1 examines aspects of the political context concerning IT workforce issues. Chapter 2 outlines a way to distinguish IT workers from a much larger class of workers whose…
ERIC Educational Resources Information Center
Sommerfeld, Kelsie; Bruce, Jackie; Jayaratne, Jay; Chapman, Ben; Gunter, Chris
2016-01-01
As part of a larger study designed to explore the gardening practices and educational needs of North Carolina chefs who cultivate restaurant gardens, the chefs' desired areas of knowledge and preferences for delivery of educational material were identified. As a result, a plan for North Carolina Cooperative Extension to use in developing…
ERIC Educational Resources Information Center
Kennamer, J. David; Chaffee, Steven H.
As part of a larger study of political socialization in adolescence, 782 adolescents and 718 parents were surveyed to test hypotheses about political information as a function of the early phase of a presidential campaign and the news exposure level of the respondent. Despite shortcomings in the sample design and in the precision of interview…
Reading Speed of Contracted French Braille
ERIC Educational Resources Information Center
Laroche, Louise; Boule, Jacinthe; Wittich, Walter
2012-01-01
This study was designed to address three hypotheses: (1) The reading speed of both readers of French braille and readers of French print will be faster in the silent condition; however, this gain in speed will be larger for print readers; (2) Individuals who acquired braille before age 10 will display faster reading speeds at lower error rates…
Using Higher Order Computer Tasks with Disadvantaged Students.
ERIC Educational Resources Information Center
Anderson, Neil
A pilot program initially designed for a 12-year-old girl with mild to moderate intellectual disabilities in higher order computer tasks was developed for a larger group of students with similar disabilities enrolled in fifth and sixth grades (ages 9-12) at three different schools. An examination of the original pilot study was undertaken to…
The Composing Processes of Three College Freshmen: Focus on Revision.
ERIC Educational Resources Information Center
Peitzman, Faye
As part of a larger research study, three freshman writers were observed in order to determine when they rewrote compositions, when they rethought major concepts and designs, and when they reviewed stylistic options and made purposive as opposed to uninformed changes in their writing. Their tape recorded comments were guided by questions on (1)…
Lifelong Learning through SMEs: Exploring Workplace Learning in the UK
ERIC Educational Resources Information Center
Ahlgren, Linda; Engel, Laura C.
2011-01-01
Purpose: The primary objective in this paper is to examine the role of small- to medium-sized enterprises (SMEs) in promoting and/or hindering educational opportunities to adult employees in the UK. Design/methodology/approach: The paper draws on 12 case studies of SMEs in England and Scotland, which form part of a larger European Sixth Framework…
Empirical Inquiry Into Teacher Centers. Teacher Education Forum; Volume 3, Number 13.
ERIC Educational Resources Information Center
Ruchkin, Judith P.
This report represents a summary of a larger, on-going investigation in teacher education committed to providing a detailed description of the differences found in teacher center and noncenter programs. Part one describes the design, and then summarizes the findings, of the initial phase of the center study by providing the answers to the six…
ERIC Educational Resources Information Center
Tate, Eleanor B.; Unger, Jennifer B.; Chou, Chih-Ping; Spruijt-Metz, Donna; Pentz, Mary Ann; Riggs, Nathaniel R.
2015-01-01
Objective: This study tested the relationships among child executive function (EF), child-perceived parent fast food intake, and child self-reported subsequent consumption of high-calorie, low-nutrient (HCLN) food. Design: One year and 6-month longitudinal observation from a larger randomized controlled trial. Setting. Southern California…
Digital Didactical Designs: Teachers' Integration of iPads for Learning-Centered Processes
ERIC Educational Resources Information Center
Jahnke, Isa; Kumar, Swapna
2014-01-01
This research presents five examples of how teachers integrated iPads into their classrooms, as part of a larger study of 15 Danish classrooms. Classroom observations and interviews with teachers revealed the use of multiple apps and a focus on creativity, production, and collaboration in the learning process. We discuss the results in the context…
Children's Perceptions of Plants Following Their Visit to the Eden Project
ERIC Educational Resources Information Center
Bowker, Rob
2004-01-01
The study described is part of a larger research programme designed to investigate primary aged children's learning during a visit to the Eden Project. Children from eight primary schools were interviewed approximately four weeks after a one-day, teacher-led visit to the Eden Project (EP) in Cornwall. Their responses revealed that the children…
Concept Study of Optical Configurations for High-Frequency Telescope for LiteBIRD
NASA Astrophysics Data System (ADS)
Hasebe, T.; Kashima, S.; Ade, P. A. R.; Akiba, Y.; Alonso, D.; Arnold, K.; Aumont, J.; Baccigalupi, C.; Barron, D.; Basak, S.; Beckman, S.; Borrill, J.; Boulanger, F.; Bucher, M.; Calabrese, E.; Chinone, Y.; Cho, H.-M.; Cukierman, A.; Curtis, D. W.; de Haan, T.; Dobbs, M.; Dominjon, A.; Dotani, T.; Duband, L.; Ducout, A.; Dunkley, J.; Duval, J. M.; Elleflot, T.; Eriksen, H. K.; Errard, J.; Fischer, J.; Fujino, T.; Funaki, T.; Fuskeland, U.; Ganga, K.; Goeckner-Wald, N.; Grain, J.; Halverson, N. W.; Hamada, T.; Hasegawa, M.; Hattori, K.; Hattori, M.; Hayes, L.; Hazumi, M.; Hidehira, N.; Hill, C. A.; Hilton, G.; Hubmayr, J.; Ichiki, K.; Iida, T.; Imada, H.; Inoue, M.; Inoue, Y.; Irwin, K. D.; Ishino, H.; Jeong, O.; Kanai, H.; Kaneko, D.; Katayama, N.; Kawasaki, T.; Kernasovskiy, S. A.; Keskitalo, R.; Kibayashi, A.; Kida, Y.; Kimura, K.; Kisner, T.; Kohri, K.; Komatsu, E.; Komatsu, K.; Kuo, C. L.; Kurinsky, N. A.; Kusaka, A.; Lazarian, A.; Lee, A. T.; Li, D.; Linder, E.; Maffei, B.; Mangilli, A.; Maki, M.; Matsumura, T.; Matsuura, S.; Meilhan, D.; Mima, S.; Minami, Y.; Mitsuda, K.; Montier, L.; Nagai, M.; Nagasaki, T.; Nagata, R.; Nakajima, M.; Nakamura, S.; Namikawa, T.; Naruse, M.; Nishino, H.; Nitta, T.; Noguchi, T.; Ogawa, H.; Oguri, S.; Okada, N.; Okamoto, A.; Okamura, T.; Otani, C.; Patanchon, G.; Pisano, G.; Rebeiz, G.; Remazeilles, M.; Richards, P. L.; Sakai, S.; Sakurai, Y.; Sato, Y.; Sato, N.; Sawada, M.; Segawa, Y.; Sekimoto, Y.; Seljak, U.; Sherwin, B. D.; Shimizu, T.; Shinozaki, K.; Stompor, R.; Sugai, H.; Sugita, H.; Suzuki, A.; Suzuki, J.; Tajima, O.; Takada, S.; Takaku, R.; Takakura, S.; Takatori, S.; Tanabe, D.; Taylor, E.; Thompson, K. L.; Thorne, B.; Tomaru, T.; Tomida, T.; Tomita, N.; Tristram, M.; Tucker, C.; Turin, P.; Tsujimoto, M.; Uozumi, S.; Utsunomiya, S.; Uzawa, Y.; Vansyngel, F.; Wehus, I. K.; Westbrook, B.; Willer, M.; Whitehorn, N.; Yamada, Y.; Yamamoto, R.; Yamasaki, N.; Yamashita, T.; Yoshida, M.
2018-05-01
The high-frequency telescope for LiteBIRD is designed with refractive and reflective optics. In order to improve sensitivity, this paper suggests the new optical configurations of the HFT which have approximately 7 times larger focal planes than that of the original design. The sensitivities of both the designs are compared, and the requirement of anti-reflection (AR) coating on the lens for the refractive option is derived. We also present the simulation result of a sub-wavelength AR structure on both surfaces of silicon, which shows a band-averaged reflection of 1.1-3.2% at 101-448 GHz.
Development of a preprototype vapor compression distillation water recovery subsystem
NASA Technical Reports Server (NTRS)
Johnson, K. L.
1978-01-01
The activities involved in the design, development, and test of a preprototype vapor compression distillation water recovery subsystem are described. This subsystem, part of a larger regenerative life support evaluation system, is designed to recover usable water from urine, urinal rinse water, and concentrated shower and laundry brine collected from three space vehicle crewmen for a period of 180 days without resupply. Details of preliminary design and testing as well as component developments are included. Trade studies, considerations leading to concept selections, problems encountered, and test data are also presented. The rework of existing hardware, subsystem development including computer programs, assembly verification, and comprehensive baseline test results are discussed.
Using walker during walking: a pilot study for health elder.
Po-Chan, Yeh; Cherng-Yee, Leung
2012-01-01
Walker operation completely relies on the walker handle, however most marketed walkers possess two horizontal handles. Several researchers have suggested that horizontal handles might lead to wrist injury. Therefore, the purpose of this study is to assess the relevant design aspects of walker for elderly people. 28 elders participated in this study; when the experiment was started, subject walked on the tile for 3 meter distance twice by using walker. Data for analysis were selected at the corresponding wrist deviation and vertical force. The results showed that during walker using, the mean wrist deviation was greater than zero. The largest vertical force is significantly larger than the smallest one, and different wrist deviation occurred at three phases, the largest wrist deviation while raising walker is larger than the smallest one, however, no significant different was found between the largest and smallest wrist deviation while pressing walker. No significant correlation occurred between weight and wrist deviation. The correlation between weight and vertical force was significantly positive. With wrist deviation walker use may cause injury to upper-limb, however wrists remain in a neutral position during hand movement to prevent damage. The findings of this study should improve the design of walker handles to reduce the wrist deviations of users.
Leonhardt, Anne; Schmukle, Stefan C; Exner, Cornelia
2016-03-01
Many studies using different assessment methods have reported personality changes after acquired brain injury (ABI). However, to our knowledge, no prospective study has yet been conducted to examine whether previous cross-sectional and retrospective results can be replicated in a longitudinal prospective design. Further, because clinical control groups were only rarely used, it remains debatable if the personality changes found are unique to patients with ABI or if they also affect patients with other disabilities. This study examined personality change in 114 participants with different kinds of ABI, 1321 matched controls (general control, GC), and 746 matched participants with restrictive impairments other than brain injury (clinical control, CC) in a prospective longitudinal design using data from the panel survey Household, Income and Labour Dynamics in Australia (HILDA). Participants with ABI showed significantly larger declines in Extraversion and Conscientiousness compared with the GC group. When the ABI participants were compared with the CC group, only the difference in Conscientiousness remained significant. Our prospective data corroborate evidence from previous cross-sectional studies that patients with ABI experience larger declines in Extraversion and Conscientiousness than the general population. Whereas the effect on Conscientiousness was unique to patients with ABI, the decline in Extraversion was also observed in participants with other impairments. Copyright © 2016 Elsevier Inc. All rights reserved.
Eyes Wide Shut: the impact of dim-light vision on neural investment in marine teleosts.
Iglesias, Teresa L; Dornburg, Alex; Warren, Dan L; Wainwright, Peter C; Schmitz, Lars; Economo, Evan P
2018-05-28
Understanding how organismal design evolves in response to environmental challenges is a central goal of evolutionary biology. In particular, assessing the extent to which environmental requirements drive general design features among distantly related groups is a major research question. The visual system is a critical sensory apparatus that evolves in response to changing light regimes. In vertebrates, the optic tectum is the primary visual processing centre of the brain and yet it is unclear how or whether this structure evolves while lineages adapt to changes in photic environment. On one hand, dim-light adaptation is associated with larger eyes and enhanced light-gathering power that could require larger information processing capacity. On the other hand, dim-light vision may evolve to maximize light sensitivity at the cost of acuity and colour sensitivity, which could require less processing power. Here, we use X-ray microtomography and phylogenetic comparative methods to examine the relationships between diel activity pattern, optic morphology, trophic guild and investment in the optic tectum across the largest radiation of vertebrates-teleost fishes. We find that despite driving the evolution of larger eyes, enhancement of the capacity for dim-light vision generally is accompanied by a decrease in investment in the optic tectum. These findings underscore the importance of considering diel activity patterns in comparative studies and demonstrate how vision plays a role in brain evolution, illuminating common design principles of the vertebrate visual system. © 2018 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2018 European Society For Evolutionary Biology.
Kiziltay, Aysel; Marcos-Fernandez, Angel; San Roman, Julio; Sousa, Rui A; Reis, Rui L; Hasirci, Vasif; Hasirci, Nesrin
2015-08-01
The present study aimed to investigate the effect of structure (design and porosity) on the matrix stiffness and osteogenic activity of stem cells cultured on poly(ester-urethane) (PEU) scaffolds. Different three-dimensional (3D) forms of scaffold were prepared from lysine-based PEU using traditional salt-leaching and advanced bioplotting techniques. The resulting scaffolds were characterized by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), mercury porosimetry and mechanical testing. The scaffolds had various pore sizes with different designs, and all were thermally stable up to 300 °C. In vitro tests, carried out using rat bone marrow stem cells (BMSCs) for bone tissue engineering, demonstrated better viability and higher cell proliferation on bioplotted scaffolds compared to salt-leached ones, most probably due to their larger and interconnected pores and stiffer nature, as shown by higher compressive moduli, which were measured by compression testing. Similarly, SEM, von Kossa staining and EDX analyses indicated higher amounts of calcium deposition on bioplotted scaffolds during cell culture. It was concluded that the design with larger interconnected porosity and stiffness has an effect on the osteogenic activity of the stem cells. Copyright © 2013 John Wiley & Sons, Ltd.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Saha, Deepak
The primary objective of the task was to characterize the materials suitable for mechanically coupled rotor, buckets and bolting operating with an inlet temperature of 760°C (1400°F). A previous study DOE-FC26-05NT42442, identified alloys such as Haynes®282®, Nimonic 105, Inconel 740, Waspaloy, Nimonic 263, and Inconel 617 as potential alloys that met the requirements for the necessary operating conditions. Of all the identified materials, Waspaloy has been widely utilized in the aviation industry in the form of disk and other smaller forgings, and sufficient material properties and vendor experience exist, for the design and manufacture of large components. The European programmore » characterizing materials for A-USC conditions are evaluating Nimonic 263 and Inconel 617 for large components. Inconel 740 has been studied extensively as a part of the boiler consortium and is code approved. Therefore, the consortium focused efforts in the development of material properties for Haynes®282® and Nimonic 105 to avoid replicative efforts and provide material choices/trade off during the detailed design of large components. Commercially available Nimonic 105 and Haynes®282® were evaluated for microstructural stability by long term thermal exposure studies. Material properties requisite for design such as tensile, creep / rupture, low cycle fatigue, high cycle fatigue, fatigue crack growth rate, hold-time fatigue, fracture toughness, and stress relaxation are documented in this report. A key requisite for the success of the program was a need demonstrate the successful scale up of the down-selected alloys, to large components. All property evaluations in the past were performed on commercially available bar/billet forms. Components in power plant equipment such as rotors and castings are several orders in magnitude larger and there is a real need to resolve the scalability issue. Nimonic 105 contains high volume fraction y’ [>50%], and hence the alloy is best suited for smaller forging and valve internals, bolts, smaller blades. Larger Nimonic 105 forgings, would precipitate y’ during the surface cooling during forging, leading to surface cracks. The associate costs in forging Nimonic 105 to larger sizes [hotter dies, press requirements], were beyond the scope of this task and not investigated further. Haynes®282® has 20 - 25% volume fraction y’ was a choice for large components, albeit untested. A larger ingot diameter is pre-requisite for a larger diameter forging and achieves the “typically” accepted working ratio of 2.5-3:1. However, Haynes®282® is manufactured via a double melt process [VIM-ESR] limited by size [<18-16” diameter], which limited the maximum size of the final forging. The report documents the development of a 24” diameter triple melt ingot, surpassing the current available technology. A second triple melt ingot was manufactured and successfully forged into a 44” diameter disk. The successful developments in triple melting process and the large diameter forging of Haynes®282® resolved the scalability issues and involved the first of its kind attempt in the world for this alloy. The complete characterization of Haynes®282® forging was performed and documented in this report. The dataset from the commercially available Haynes®282® [grain size ASTM 3-4] and the finer grain size disk forging [ASTM 8-9] offer an additional design tradeoff to balance creep and fatigue during the future design process.« less
Design of a piezoelectric shaker for centrifuge testing
NASA Technical Reports Server (NTRS)
Canclini, J. G.; Henderson, J. M.
1979-01-01
The design of a prototype piezoelectric shaker and its development to date is described. Although certain design problems remain to be solved, the piezoelectric system shows promise for adaptation to a larger payload system, such as the proposed geotechnical centrifuge at the Ames Research Center.
Development of test procedure for the design of black base : final report.
DOT National Transportation Integrated Search
1976-01-01
There is no standard design procedure available for black base mixes containing aggregates larger than 1" (25.4 mm) This investigation dealt with the use of stability testing equipment similar to that used in the design of surface mixes and developme...
Wheelchair Design Changes: New Opportunities for Recreation.
ERIC Educational Resources Information Center
Exceptional Parent, 1984
1984-01-01
Changes in wheelchair design (such as larger tires and lighter overall weight) make it possible for disabled persons to exercise more mobility and control and participate in a greater variety of recreational activities. (CL)
NASA Technical Reports Server (NTRS)
Zapata, R. N.; Humphris, R. R.; Henderson, K. C.
1975-01-01
The basic research and development work towards proving the feasibility of operating an all-superconductor magnetic suspension and balance device for aerodynamic testing is presented. The feasibility of applying a quasi-six-degree-of freedom free support technique to dynamic stability research was studied along with the design concepts and parameters for applying magnetic suspension techniques to large-scale aerodynamic facilities. A prototype aerodynamic test facility was implemented. Relevant aspects of the development of the prototype facility are described in three sections: (1) design characteristics; (2) operational characteristics; and (3) scaling to larger facilities.
Portable Life Support System 2.5 Fan Design and Development
NASA Technical Reports Server (NTRS)
Quinn, Gregory; Carra, Michael; Converse, David; Chullen, Cinda
2016-01-01
NASA is building a high-fidelity prototype of an advanced Portable Life Support System (PLSS) as part of the Advanced Exploration Systems Program. This new PLSS, designated as PLSS 2.5, will advance component technologies and systems knowledge to inform a future flight program. The oxygen ventilation loop of its predecessor, PLSS 2.0, was driven by a centrifugal fan developed using specifications from the Constellation Program. PLSS technology and system parameters have matured to the point where the existing fan will not perform adequately for the new prototype. In addition, areas of potential improvement were identified with the PLSS 2.0 fan that could be addressed in a new design. As a result, a new fan was designed and tested for the PLSS 2.5. The PLSS 2.5 fan is a derivative of the one used in PLSS 2.0, and it uses the same nonmetallic, canned motor, with a larger volute and impeller to meet the higher pressure drop requirements of the PLSS 2.5 ventilation loop. The larger impeller allows it to operate at rotational speeds that are matched to rolling element bearings, and which create reasonably low impeller tip speeds consistent with prior, oxygen-rated fans. Development of the fan also considered a shrouded impeller design that could allow larger clearances for greater oxygen safety, assembly tolerances and particle ingestion. This paper discusses the design, manufacturing and performance testing of the new fans.
Ganz, Jennifer B; Rispoli, Mandy J; Mason, Rose Ann; Hong, Ee Rea
2014-06-01
The purpose of this meta-analysis was to evaluate the potential moderating effects of intervention setting and type of aided augmentative and alternative communication (AAC) on outcome variables for students with autism spectrum disorders. Improvement rate difference, an effect size measure, was used to calculate aggregate effects across 35 single-case research studies. Results indicated that the largest effects for aided AAC were observed in general education settings. With respect to communication outcomes, both speech generating devices (SGDs) and the Picture Exchange Communication System (PECS) were associated with larger effects than other picture-based systems. With respect to challenging behaviour outcomes, SGDs produced larger effects than PECS. This aggregate study highlights the importance of considering intervention setting, choice of AAC system and target outcomes when designing and planning an aided AAC intervention.
Armen, Roger S.; Schiller, Stefan M.; Brooks, Charles L.
2015-01-01
Orthogonal aminoacyl-tRNA synthetase/tRNA pairs from archaea have been evolved to facilitate site specific in vivo incorporation of unnatural amino acids into proteins in Escherichia coli. Using this approach, unnatural amino acids have been successfully incorporated with high translational efficiency and fidelity. In this study, CHARMM-based molecular docking and free energy calculations were used to evaluate rational design of specific protein-ligand interactions for aminoacyl-tRNA synthetases. A series of novel unnatural amino acid ligands were docked into the p-benzoyl-L-phenylalanine tRNA synthetase, which revealed that the binding pocket of the enzyme does not provide sufficient space for significantly larger ligands. Specific binding site residues were mutated to alanine to create additional space to accommodate larger target ligands, and then mutations were introduced to improve binding free energy. This approach was used to redesign binding sites for several different target ligands, which were then tested against the standard 20 amino acids to verify target specificity. Only the synthetase designed to bind Man-α-O-Tyr was predicted to be sufficiently selective for the target ligand and also thermodynamically stable. Our study suggests that extensive redesign of the tRNA synthatase binding pocket for large bulky ligands may be quite thermodynamically unfavorable. PMID:20310065
Assessment of Scaled Rotors for Wind Tunnel Experiments.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Maniaci, David Charles; Kelley, Christopher Lee; Chiu, Phillip
2015-07-01
Rotor design and analysis work has been performed to support the conceptualization of a wind tunnel test focused on studying wake dynamics. This wind tunnel test would serve as part of a larger model validation campaign that is part of the Department of Energy Wind and Water Power Program’s Atmosphere to electrons (A2e) initiative. The first phase of this effort was directed towards designing a functionally scaled rotor based on the same design process and target full-scale turbine used for new rotors for the DOE/SNL SWiFT site. The second phase focused on assessing the capabilities of an already available rotor,more » the G1, designed and built by researchers at the Technical University of München.« less
Knowledge-based critiquing of graphical user interfaces with CHIMES
NASA Technical Reports Server (NTRS)
Jiang, Jianping; Murphy, Elizabeth D.; Carter, Leslie E.; Truszkowski, Walter F.
1994-01-01
CHIMES is a critiquing tool that automates the process of checking graphical user interface (GUI) designs for compliance with human factors design guidelines and toolkit style guides. The current prototype identifies instances of non-compliance and presents problem statements, advice, and tips to the GUI designer. Changes requested by the designer are made automatically, and the revised GUI is re-evaluated. A case study conducted at NASA-Goddard showed that CHIMES has the potential for dramatically reducing the time formerly spent in hands-on consistency checking. Capabilities recently added to CHIMES include exception handling and rule building. CHIMES is intended for use prior to usability testing as a means, for example, of catching and correcting syntactic inconsistencies in a larger user interface.
A spaceborne optical interferometer: The JPL CSI mission focus
NASA Astrophysics Data System (ADS)
Laskin, R. A.
1989-08-01
The JPL Control Structure Interaction (CSI) program is part of the larger NASA-wide CSI program. Within this larger context, the JPL CSI program will emphasize technology for systems that demand micron or sub-micron level control, so-called Micro-Precision Controlled Structures (u-PCS). The development of such technology will make it practical to fly missions with large optical or large precision antenna systems. In keeping with the focused nature of the desired technology, the JPL approach is to identify a focus mission, develop the focus mission CSI system design to a preliminary level, and then use this design to drive out requirements for CSI technology development in the design and analysis, ground test bed, and flight experiment areas.
NASA Technical Reports Server (NTRS)
Bolding, R. M.; Stearman, R. O.
1976-01-01
A low budget flutter model incorporating active aerodynamic controls for flutter suppression studies was designed as both an educational and research tool to study the interfering lifting surface flutter phenomenon in the form of a swept wing-tail configuration. A flutter suppression mechanism was demonstrated on a simple semirigid three-degree-of-freedom flutter model of this configuration employing an active stabilator control, and was then verified analytically using a doublet lattice lifting surface code and the model's measured mass, mode shapes, and frequencies in a flutter analysis. Preliminary studies were significantly encouraging to extend the analysis to the larger degree of freedom AFFDL wing-tail flutter model where additional analytical flutter suppression studies indicated significant gains in flutter margins could be achieved. The analytical and experimental design of a flutter suppression system for the AFFDL model is presented along with the results of a preliminary passive flutter test.
Advanced Cogeneration Technology Economic Optimization Study (ACTEOS)
NASA Technical Reports Server (NTRS)
Nanda, P.; Ansu, Y.; Manuel, E. H., Jr.; Price, W. G., Jr.
1980-01-01
The advanced cogeneration technology economic optimization study (ACTEOS) was undertaken to extend the results of the cogeneration technology alternatives study (CTAS). Cost comparisons were made between designs involving advanced cogeneration technologies and designs involving either conventional cogeneration technologies or not involving cogeneration. For the specific equipment cost and fuel price assumptions made, it was found that: (1) coal based cogeneration systems offered appreciable cost savings over the no cogeneration case, while systems using coal derived liquids offered no costs savings; and (2) the advanced cogeneration systems provided somewhat larger cost savings than the conventional systems. Among the issues considered in the study included: (1) temporal variations in steam and electric demands; (2) requirements for reliability/standby capacity; (3) availability of discrete equipment sizes; (4) regional variations in fuel and electricity prices; (5) off design system performance; and (6) separate demand and energy charges for purchased electricity.
29 CFR 1910.211 - Definitions.
Code of Federal Regulations, 2014 CFR
2014-07-01
... inches diameter and larger, specially designed for use on cutting-off machines where mounting nut or... enclosure designed to restrain the pieces of the grinding wheel and furnish all possible protection in the... designed and fully guarded machines and are subject to the following maximum thickness and hole size...
The impact of cigarette pack design, descriptors, and warning labels on risk perception in the U.S.
Bansal-Travers, Maansi; Hammond, David; Smith, Philip; Cummings, K Michael
2011-06-01
In the U.S., limited evidence exists on the impact of colors and brand imagery used in cigarette pack design. This study examined the impact of pack design, product descriptors, and health warnings on risk perception and brand appeal. A cross-sectional mall-intercept study was conducted with 197 adult smokers and 200 nonsmokers in Buffalo NY from June to July 2009 (data analysis from July 2009 to December 2010). Participants were shown 12 sets of packs randomly; each set varied by a particular design feature (color, descriptor) or warning label style (text versus graphic, size, attribution, message framing). Packs were rated on criteria including risk perceptions, quit motivation, and purchase interest. Participants selected larger, pictorial, and loss-framed warning labels as more likely to attract attention, encourage thoughts about health risks, motivate quitting, and be most effective. Participants were more likely to select packs with lighter color shading and descriptors such as light, silver, and smooth as delivering less tar, smoother taste, and lower health risk, compared to darker-shaded or full-flavor packs. Additionally, participants were more likely to select the branded compared to plain white pack when asked which delivered the most tar, smoothest taste, was more attractive, appealed to youth aged <18 years, and contained cigarettes of better quality. The findings support larger, graphic health warnings that convey loss-framed messages as most effective in communicating health risks to U.S. adults. The results also indicate that color and product descriptors are associated with false beliefs about risks. Plain packaging may reduce many of the erroneous misperceptions of risk communicated through pack design features. Copyright © 2011 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.
The Impact of Cigarette Pack Design, Descriptors, and Warning Labels on Risk Perception in the U.S
Bansal-Travers, Maansi; Hammond, David; Smith, Philip; Cummings, K. Michael
2011-01-01
Background In the U.S., limited evidence exists on the impact of colors and brand imagery used in cigarette pack design. Purpose This study examined the impact of pack design, product descriptors, and health warnings on risk perception and brand appeal. Methods A cross-sectional mall-intercept study was conducted with 197 adult smokers and 200 nonsmokers in Buffalo, NY from June to July 2009 (data analysis from July 2009 to December 2010). Participants were shown 12 sets of packs randomly; each set varied by a particular design feature (color, descriptor) or warning label style (text vs graphic, size, attribution, message framing). Packs were rated on criteria including risk perceptions, quit motivation, and purchase interest. Results Participants selected larger, pictorial, and loss-framed warning labels as more likely to attract attention, encourage thoughts about health risks, motivate quitting, and most effective. Participants were more likely to select packs with lighter color shading and descriptors such as light, silver, and smooth as delivering less tar, smoother taste, and lower health risk, compared to darker-shaded or full flavor packs. Additionally, participants were more likely to select the branded compared to plain white pack when asked which delivered the most tar, smoothest taste, was more attractive, appealed to youth aged <18 years, and contained cigarettes of better quality. Conclusions The findings support larger, graphic health warnings that convey loss-framed messages as most effective in communicating health risks to U.S. adults. The results also indicate that color and product descriptors are associated with false beliefs about risks. Plain packaging may reduce many of the erroneous misperceptions of risk communicated through pack design features. PMID:21565661
Development, implementation, and test results on integrated optics switching matrix
NASA Technical Reports Server (NTRS)
Rutz, E.
1982-01-01
A small integrated optics switching matrix, which was developed, implemented, and tested, indicates high performance. The matrix serves as a model for the design of larger switching matrices. The larger integrated optics switching matrix should form the integral part of a switching center with high data rate throughput of up to 300 megabits per second. The switching matrix technique can accomplish the design goals of low crosstalk and low distortion. About 50 illustrations help explain and depict the many phases of the integrated optics switching matrix. Many equations used to explain and calculate the experimental data are also included.
Downwind pre-aligned rotors for extreme-scale wind turbines
Loth, Eric; Steele, Adam; Qin, Chao; ...
2017-03-08
Downwind force angles are small for current turbines systems (1-5 MW) such that they may be readily accommodated by conventional upwind configurations. However, analysis indicates that extreme-scale systems (10-20 MW) will have larger angles that may benefit from downwind-aligned configurations. To examine potential rotor mass reduction, the pre-alignment concept was investigated a two-bladed configuration by keeping the structural and aerodynamic characteristics of each blade fixed (to avoids a complete blade re-design). Simulations for a 13.2 MW rated rotor at steady-state conditions show that this concept-level two-bladed design may yield 25% rotor mass savings while also reducing average blade stress overmore » all wind speeds. These results employed a pre-alignment on the basis of a wind speed of 1.25 times the rated wind speed. The downwind pre-aligned concept may also reduce damage equivalent loads on the blades by 60% for steady rated wind conditions. Even higher mass and damage equivalent load savings (relative to conventional upwind designs) may be possible for larger systems (15-20 MW) for which load-alignment angles become even larger. Furthermore, much more work is needed to determine whether this concept can be translated into a practical design that must meet a wide myriad of other criteria.« less
Downwind pre-aligned rotors for extreme-scale wind turbines
DOE Office of Scientific and Technical Information (OSTI.GOV)
Loth, Eric; Steele, Adam; Qin, Chao
Downwind force angles are small for current turbines systems (1-5 MW) such that they may be readily accommodated by conventional upwind configurations. However, analysis indicates that extreme-scale systems (10-20 MW) will have larger angles that may benefit from downwind-aligned configurations. To examine potential rotor mass reduction, the pre-alignment concept was investigated a two-bladed configuration by keeping the structural and aerodynamic characteristics of each blade fixed (to avoids a complete blade re-design). Simulations for a 13.2 MW rated rotor at steady-state conditions show that this concept-level two-bladed design may yield 25% rotor mass savings while also reducing average blade stress overmore » all wind speeds. These results employed a pre-alignment on the basis of a wind speed of 1.25 times the rated wind speed. The downwind pre-aligned concept may also reduce damage equivalent loads on the blades by 60% for steady rated wind conditions. Even higher mass and damage equivalent load savings (relative to conventional upwind designs) may be possible for larger systems (15-20 MW) for which load-alignment angles become even larger. Furthermore, much more work is needed to determine whether this concept can be translated into a practical design that must meet a wide myriad of other criteria.« less
Robust Grasp Design Using Grasp Force Focus Positioning
1991-12-12
the time for reviewing instructons. search-ng e isting date sources. gathering and maintainng the data needed, and completing and review ng the...of a larger scale task currently being studied at AFIT; a task which demonstrates intelligent part mating skills. The specific task involves the use of...program to generate the appropriate data for graphical analysis. The robotic hand model used in this study is based on the Utah/MIT Dexterous
Davies, C
1997-01-01
The study aimed to explore nurses knowledge and attitudes towards brain stem death and organ donation. An ex post facto research design was used to determine relationships between variables. A 16 item questionnaire was used to collect data. Statistical analysis revealed one significant result. The limitations of the sample size is acknowledged and the conclusion suggests a larger study is required.
Smoking, caning, and delinquency in a secondary modern school.
Palmer, J W
2015-02-01
This study was designed in 1962 to investigate the reformative effect of a particular punishment (caning) for a particular offence (smoking by schoolboys). In 1964, in the course of a larger study of juvenile offences, delinquency records were obtained from the police, and the relationship between smoking and delinquency is also discussed in this paper. © The Author 2015; all rights reserved. Published by Oxford University Press on behalf of the International Epidemiological Association.
Designing from Their Own Social Worlds: The Digital Story of Three African American Young Women
ERIC Educational Resources Information Center
Hall, Ted
2011-01-01
In this paper I examine the literacy work of three African American young women (through data drawn from a larger qualitative study), particularly their ways of knowing, such as double consciousness (Du Bois, 1989), and the multiple subject positions they occupy as they write themselves into a digitally created story. My analysis is guided by the…
ERIC Educational Resources Information Center
Skinner, Ellen; Pitzer, Jennifer; Steele, Joel
2013-01-01
A study was designed to examine a multidimensional measure of children's coping in the academic domain as part of a larger model of motivational resilience. Using items tapping multiple ways of dealing with academic problems, including five adaptive ways (strategizing, help-seeking, comfort-seeking, self-encouragement, and commitment) and six…
Gender Identities and Career Aspirations of Middle Leaders: Cases in Hong Kong Secondary Schools
ERIC Educational Resources Information Center
Choi, Pik Lin
2013-01-01
Purpose: The purpose of this paper is to examine gender identities of Chinese male and female middle leaders in secondary schools and how gender dynamics play in the leadership process and impact on career aspirations and career development. Design/methodology/approach: This paper draws on the data of a larger qualitative study conducted using the…
ERIC Educational Resources Information Center
Thurlow, Martha; Albus, Deb; Shyyan, Vitaliy; Liu, Kristin; Barrera, Manuel
2004-01-01
The study reported here was conducted as part of a larger investigation designed to identify instructional strategies most beneficial for English language learners with disabilities. Other aspects of the investigation are examining the research literature, information from parents and students, and the effects of specific strategies. In this…
Japan in the Classroom: Elementary and Secondary Activities, Revised Edition.
ERIC Educational Resources Information Center
Parisi, Lynn; And Others
This activity book is designed to present information and insights on Japanese culture and society. Because few teachers can devote entire units to the study of Japan, the activities focus on teaching about Japan within the context of larger social science units. Some of the lessons can be taught within the context of the humanities and fine arts,…
Continuity and Discontinuity: The Case of Second Couplehood in Old Age
ERIC Educational Resources Information Center
Koren, Chaya
2011-01-01
Purpose: Continuity and discontinuity are controversial concepts in social theories on aging. The aim of this article is to explore these concepts using the experiences of older persons living in second couplehood in old age as a case in point. Design and Method: Based on a larger qualitative study on second couplehood in old age, following the…
Educational Middle Change Leadership in New Zealand: The Meat in the Sandwich
ERIC Educational Resources Information Center
Marshall, Steven Gregory
2012-01-01
Purpose: The purpose of this paper is to report findings from a larger study into the role of middle leaders of change in New Zealand higher education. Design/methodology/approach: In total, ten middle leaders from the New Zealand higher education sector took part in a recent research project which examined successful change leadership in higher…
ERIC Educational Resources Information Center
Ee, Jessie
2014-01-01
This paper discusses the use of an alternative instrument to assess the social-emotional competence (SEC) of secondary school students in Singapore. The instrument was used in a larger study to explore an approach to infuse social-emotional learning in the curriculum for children in school. The design of this research instrument is based on the…
ERIC Educational Resources Information Center
Lonsway, Kimberly A.; Klaw, Elena L.; Berg, Dianne R.; Waldo, Craig R.; Kothari, Chevon; Mazurek, Christopher J.; Hegeman, Kurt E.
As part of a larger multimethod evaluation, the present study examined the effects of a uniquely intensive rape education program. Participants included 74 undergraduates (53 women and 21 men) enrolled in Campus Acquaintance Rape Education (CARE), a semester-long university course designed to train peer facilitators to conduct rape education…
Runway Independent Aircraft Extremely Short Takeoff and Landing Regional Airliner: The Model 110
NASA Technical Reports Server (NTRS)
Hall, David W.
2003-01-01
Airports throughout the United States are plagued with growing congestion. With the increase in air traffic predicted in the next few years, congestion will worsen. The accepted solution of building larger airplanes to carry more travelers is no longer a viable option, as airports are unable to accommodate larger aircraft without expensive infrastructure changes. Past NASA research has pointed to the need for a new approach, which can economically and safely utilize smaller airports. To study this option further, NASA requested the California Polytechnic State University at San Luis Obispo (Cal Poly/SLO) to design a baseline aircraft to be used for system studies. The requirements put forth by NASA are summarized. The design team was requested to create a demonstrator vehicle, which could be built without requiring enabling technology development. To this end, NASA requested that the tested and proven high-lift system of the Boeing C-17 Globemaster III be combined with the fuselage of the BAe-146. NASA also requested that Cal Poly determine the availability and usability of underutilized airports starting with California, then expanding if time and funds permitted to the U.S.
NASA Technical Reports Server (NTRS)
Thompson, R. A.; Sutton, Kenneth
1987-01-01
A computational analysis, modification, and preliminary redesign study was performed on the nozzle contour of the Langley Hypersonic CF4 Tunnel. This study showed that the existing nozzle was contoured incorrectly for the design operating condition, and this error was shown to produce the measured disturbances in the exit flow field. A modified contour was designed for the current nozzle downstream of the maximum turning point that would provide a uniform exit flow. New nozzle contours were also designed for an exit Mach number and Reynolds number combination which matches that attainable in the Langley 20-Inch Mach 6 Tunnel. Two nozzle contours were designed: one having the same exit radius but a larger mass flow rate than that of the existing CF4 Tunnel, and the other having the same mass flow rate but a smaller exit radius than that of the existing CF4 Tunnel.
Comprehensive Educational Assessment for the States: The Duplex Design.
ERIC Educational Resources Information Center
Bock, R. Darrell; Mislevy, Robert J.
1988-01-01
The duplex design is proposed for educational assessment within a state school system. For individual students, scaled proficiency measures that are suitable for guidance and certification at various levels of attainment are provided. For classrooms or larger units, the design can supply group level measures for evaluation and research. (SLD)
Maximum life spiral bevel reduction design
NASA Technical Reports Server (NTRS)
Savage, M.; Prasanna, M. G.; Coe, H. H.
1992-01-01
Optimization is applied to the design of a spiral bevel gear reduction for maximum life at a given size. A modified feasible directions search algorithm permits a wide variety of inequality constraints and exact design requirements to be met with low sensitivity to initial values. Gear tooth bending strength and minimum contact ratio under load are included in the active constraints. The optimal design of the spiral bevel gear reduction includes the selection of bearing and shaft proportions in addition to gear mesh parameters. System life is maximized subject to a fixed back-cone distance of the spiral bevel gear set for a specified speed ratio, shaft angle, input torque, and power. Significant parameters in the design are: the spiral angle, the pressure angle, the numbers of teeth on the pinion and gear, and the location and size of the four support bearings. Interpolated polynomials expand the discrete bearing properties and proportions into continuous variables for gradient optimization. After finding the continuous optimum, a designer can analyze near optimal designs for comparison and selection. Design examples show the influence of the bearing lives on the gear parameters in the optimal configurations. For a fixed back-cone distance, optimal designs with larger shaft angles have larger service lives.
van Hengel, Ingmar A J; Riool, Martijn; Fratila-Apachitei, Lidy E; Witte-Bouma, Janneke; Farrell, Eric; Zadpoor, Amir A; Zaat, Sebastian A J; Apachitei, Iulian
2017-09-01
Implant-associated infection and limited longevity are two major challenges that orthopedic devices need to simultaneously address. Additively manufactured porous implants have recently shown tremendous promise in improving bone regeneration and osseointegration, but, as any conventional implant, are threatened by infection. In this study, we therefore used rational design and additive manufacturing in the form of selective laser melting (SLM) to fabricate porous titanium implants with interconnected pores, resulting in a 3.75 times larger surface area than corresponding solid implants. The SLM implants were biofunctionalized by embedding silver nanoparticles in an oxide surface layer grown using plasma electrolytic oxidation (PEO) in Ca/P-based electrolytes. The PEO layer of the SLM implants released silver ions for at least 28 days. X-ray diffraction analysis detected hydroxyapatite on the SLM PEO implants but not on the corresponding solid implants. In vitro and ex vivo assays showed strong antimicrobial activity of these novel SLM PEO silver-releasing implants, without any signs of cytotoxicity. The rationally designed SLM porous implants outperformed solid implants with similar dimensions undergoing the same biofunctionalization treatment. This included four times larger amount of released silver ions, two times larger zone of inhibition, and one additional order of magnitude of reduction in numbers of CFU in an ex vivo mouse infection model. Copyright © 2017 Elsevier Ltd. All rights reserved.
Pütter, Carolin; Pechlivanis, Sonali; Nöthen, Markus M; Jöckel, Karl-Heinz; Wichmann, Heinz-Erich; Scherag, André
2011-01-01
Genome-wide association studies have identified robust associations between single nucleotide polymorphisms and complex traits. As the proportion of phenotypic variance explained is still limited for most of the traits, larger and larger meta-analyses are being conducted to detect additional associations. Here we investigate the impact of the study design and the underlying assumption about the true genetic effect in a bimodal mixture situation on the power to detect associations. We performed simulations of quantitative phenotypes analysed by standard linear regression and dichotomized case-control data sets from the extremes of the quantitative trait analysed by standard logistic regression. Using linear regression, markers with an effect in the extremes of the traits were almost undetectable, whereas analysing extremes by case-control design had superior power even for much smaller sample sizes. Two real data examples are provided to support our theoretical findings and to explore our mixture and parameter assumption. Our findings support the idea to re-analyse the available meta-analysis data sets to detect new loci in the extremes. Moreover, our investigation offers an explanation for discrepant findings when analysing quantitative traits in the general population and in the extremes. Copyright © 2011 S. Karger AG, Basel.
NASA Astrophysics Data System (ADS)
Cao, Q.; Qiu, L. M.; Zhi, X. Q.; Han, L.; Gan, Z. H.; Zhang, X. B.; Zhang, X. J.; Sun, D. M.
2013-12-01
The impedance magnitude is important for the design and operation of a Stirling pulse tube cryocooler (SPTC). However, the influence of the impedance magnitude on the SPTC working at liquid-helium temperatures is still not clear due to the complexity of refrigeration mechanism at this temperature range. In this study, the influence of the impedance magnitude on the viscous and thermal losses has been investigated, which contributes to the overall refrigeration efficiency. Different from the previous study at liquid nitrogen temperatures, it has been found and verified experimentally that a higher impedance magnitude may result in a larger mass flow rate accompanied with larger losses in the warmer region, hence the refrigeration efficiency is lowered. Numerical simulation is carried out in SPTCs of different geometry dimensions and working parameters, and the experimental study is carried out in a three-stage SPTC. A minimum no-load refrigeration temperature is achieved with an appropriate impedance magnitude that is determined by the combination of frequency and precooling temperature. A lowest temperature of 4.76 K is achieved at 28 Hz and a precooling temperature of 22.6 K, which is the lowest temperature ever achieved with He-4 for SPTCs. Impedance magnitude optimization is clearly an important consideration for the design of a 4 K SPTC.
D. Czokajlo; B. Hrasovec; M. Pernek; J. Hilszczanski; A. Kolk; S. Teale; J. Wickham; P. Kirsch
2003-01-01
An optimized, patented lure for the larger pine shoot beetle, Tomicus piniperda has been developed and tested in the United States, Poland, and Croatia. Seven different beetle attractants were tested: α-pinene, α-pinene oxide, ethanol, nonanal, myrtenal, myrtenol, and trans-verbenol. α-pinene was tested...
NASA Astrophysics Data System (ADS)
Wu, J. F.; Li, Y.
2014-10-01
High-temperature superconductors (HTSCs) array with aligned growth section boundary (GSB) pattern (AGSBP) exhibits larger levitation force and suppression of levitation force decay above a permanent magnet guideway (PMG) compared with misaligned GSB pattern (MGSBP) has been studied in maglev train application (Zheng et al., 2013). This result maybe helpful and support a new way for the HTS bearing design for flywheel systems. So, in this paper, we further examine this growth anisotropy effect on the maglev performance of flywheel system. Levitation force and coasting time were investigated from the point-view of HTS flywheel applications. The GS/GSB alignment of AGSBP bulk HTSCs produces larger levitation force than that of MGSBP, but the coasting time is shorter than that of MGSBP, that is to say, the electric magnetic drag force with AGSBP is larger than that of MGSBP. This result may also exist in the maglev guideline when the maglev train stops freely.
Shape accuracy requirements on starshades for large and small apertures
NASA Astrophysics Data System (ADS)
Shaklan, Stuart B.; Marchen, Luis; Cady, Eric
2017-09-01
Starshades have been designed to work with large and small telescopes alike. With smaller telescopes, the targets tend to be brighter and closer to the Solar System, and their putative planetary systems span angles that require starshades with radii of 10-30 m at distances of 10s of Mm. With larger apertures, the light-collecting power enables studies of more numerous, fainter systems, requiring larger, more distant starshades with radii >50 m at distances of 100s of Mm. Characterization using infrared wavelengths requires even larger starshades. A mitigating approach is to observe planets between the petals, where one can observe regions closer to the star but with reduced throughput and increased instrument scatter. We compare the starshade shape requirements, including petal shape, petal positioning, and other key terms, for the WFIRST 26m starshade and the HABEX 72 m starshade concepts, over a range of working angles and telescope sizes. We also compare starshades having rippled and smooth edges and show that their performance is nearly identical.
Investigations into a potential laser-NASP transport technology
NASA Technical Reports Server (NTRS)
1990-01-01
Laser propelled flight/transport technology is surveyed. A detailed conceptual design is presented for an on-place Mercury-Lightcraft: other designs are briefly explored for larger, 15-place Executive Lightcraft, and 150 to 350 passenger Jumbo Lightcraft.
Why the bigger live longer and travel farther: animals, vehicles, rivers and the winds.
Bejan, Adrian
2012-01-01
Here we show that constructal-law physics unifies the design of animate and inanimate movement by requiring that larger bodies move farther, and their movement on the landscape last longer. The life span of mammals must scale as the body mass (M) raised to the power 1/4, and the distance traveled during the lifetime must increase with body size. The same size effect on life span and distance traveled holds for the other flows that move mass on earth: atmospheric and oceanic jets and plumes, river basins, animals and human operated vehicles. The physics is the same for all flow systems on the landscape: the scaling rules of "design" are expressions of the natural tendency of all flow systems to generate designs that facilitate flow access. This natural tendency is the constructal law of design and evolution in nature. Larger bodies are more efficient movers of mass on the landscape.
Building large telescopes in orbit using small satellites
NASA Astrophysics Data System (ADS)
Saunders, Chris; Lobb, Dan; Sweeting, Martin; Gao, Yang
2017-12-01
In many types of space mission there is a constant desire for larger and larger instrument apertures, primarily for the purposes of increased resolution or sensitivity. In the Radio Frequency domain, this is currently addressed by antennas that unfold or deploy on-orbit. However, in the optical and infrared domains, this is a significantly more challenging problem, and has up to now either been addressed by simply having large monolithic mirrors (which are fundamentally limited by the volume and mass lifting capacity of any launch vehicle) or by complex 'semi-folding' designs such as the James Webb Space Telescope. An alternative is to consider a fractionated instrument which is launched as a collection of individual smaller elements which are then assembled (or self-assemble) once in space, to form a much larger overall instrument. SSTL has been performing early concept assessment work on such systems for high resolution science observations from high orbits (potentially also for persistent surveillance of Earth). A point design of a 25 m sparse aperture (annular ring) telescope is presented. Key characteristics of 1) multiple small elements launched separately and 2) on-orbit assembly to form a larger instrument are included in the architecture. However, on-orbit assembly brings its own challenges in terms of guidance navigation and control, robotics, docking mechanisms, system control and data handling, optical alignment and stability, and many other elements. The number and type of launchers used, and the technologies and systems used heavily affect the outcome and general cost of the telescope. The paper describes one of the fractionated architecture concepts currently being studied by SSTL, including the key technologies and operational concepts that may be possible in the future.
NASA Technical Reports Server (NTRS)
Tomberlin, T. J.
1985-01-01
Research studies of residents' responses to noise consist of interviews with samples of individuals who are drawn from a number of different compact study areas. The statistical techniques developed provide a basis for those sample design decisions. These techniques are suitable for a wide range of sample survey applications. A sample may consist of a random sample of residents selected from a sample of compact study areas, or in a more complex design, of a sample of residents selected from a sample of larger areas (e.g., cities). The techniques may be applied to estimates of the effects on annoyance of noise level, numbers of noise events, the time-of-day of the events, ambient noise levels, or other factors. Methods are provided for determining, in advance, how accurately these effects can be estimated for different sample sizes and study designs. Using a simple cost function, they also provide for optimum allocation of the sample across the stages of the design for estimating these effects. These techniques are developed via a regression model in which the regression coefficients are assumed to be random, with components of variance associated with the various stages of a multi-stage sample design.
Diversification of Processors Based on Redundancy in Instruction Set
NASA Astrophysics Data System (ADS)
Ichikawa, Shuichi; Sawada, Takashi; Hata, Hisashi
By diversifying processor architecture, computer software is expected to be more resistant to plagiarism, analysis, and attacks. This study presents a new method to diversify instruction set architecture (ISA) by utilizing the redundancy in the instruction set. Our method is particularly suited for embedded systems implemented with FPGA technology, and realizes a genuine instruction set randomization, which has not been provided by the preceding studies. The evaluation results on four typical ISAs indicate that our scheme can provide a far larger degree of freedom than the preceding studies. Diversified processors based on MIPS architecture were actually implemented and evaluated with Xilinx Spartan-3 FPGA. The increase of logic scale was modest: 5.1% in Specialized design and 3.6% in RAM-mapped design. The performance overhead was also modest: 3.4% in Specialized design and 11.6% in RAM-mapped design. From these results, our scheme is regarded as a practical and promising way to secure FPGA-based embedded systems.
Eagle, Shawn R.; Connaboy, Chris; Nindl, Bradley C.; Allison, Katelyn F.
2018-01-01
Background: Musculoskeletal injuries to the extremities are a primary concern for the United States (US) military. One possible injury risk factor in this population is side-to-side strength imbalance. Purpose: To examine the odds of reporting a previous shoulder injury in US Marine Corps Ground Combat Element Integrated Task Force volunteers based on side-to-side strength differences in isokinetic shoulder strength. Study Design: Cohort study; Level of evidence, 3. Methods: Male (n = 219) and female (n = 91) Marines were included in this analysis. Peak torque values from 5 shoulder internal/external rotation repetitions were averaged and normalized to body weight. The difference in side-to-side strength measurements was calculated as the absolute value of the limb difference divided by the mean peak torque of the dominant limb. Participants were placed into groups based on the magnitude of these differences: <10%, 10% to 20%, and >20%. Odds ratios (ORs) and 95% CIs were calculated. Results: When separated by sex, 13.2% of men reported an injury, while 5.5% of women reported an injury. Female Marines with >20% internal rotation side-to-side strength differences demonstrated increased odds of reporting a previous shoulder injury compared with female Marines with <10% strength differences (OR, 15.4; 95% CI, 1.4-167.2; P = .03 ) and female Marines with 10% to 20% strength differences (OR, 13.9; 95% CI, 1.3-151.2; P = .04). No significant ORs were demonstrated in male Marines. Conclusion: Marines with larger magnitude internal rotation strength differences demonstrated increased odds of reporting a previous shoulder injury compared with those with lesser magnitude differences. Additionally, female sex appears to drastically affect the increased odds of reporting shoulder injuries (OR, 13.9-15.4) with larger magnitude differences (ie, >20%) compared with those with lesser magnitude differences (ie, <10% and 10%-20%). The retrospective cohort design of this study cannot delineate cause and effect but establishes a relationship between female Marines and greater odds of larger magnitude strength differences after returning from an injury. PMID:29497623
Johri, Mira; Chandra, Dinesh; Koné, Georges K; Dudeja, Sakshi; Sylvestre, Marie-Pierre; Sharma, Jitendar K; Pahwa, Smriti
2015-01-01
Objective With the aim of conducting a future cluster randomised trial to assess intervention impact on child vaccination coverage, we designed a pilot study to assess feasibility and aid in refining methods for the larger study. Trial design Cluster-randomised design with a 1:1 allocation ratio. Methods Clusters were 12 villages in rural Uttar Pradesh. All women residing in a selected village who were mothers of a child 0–23 months of age were eligible; participants were chosen at random. Over 4 months, intervention group (IG) villages received: (1) home visits by volunteers; (2) community mobilisation events to promote immunisation. Control group (CG) villages received community mobilisation to promote nutrition. A toll-free number for immunisation was offered to all IG and CG village residents. Primary outcomes were ex-ante criteria for feasibility of the main study related to processes for recruitment and randomisation (50% of villages would agree to participate and accept randomisation; 30 women could be recruited in 70% of villages), and retention of participants (50% of women retained from baseline to endline). Clusters were assigned to IG or CG using a computer-generated randomisation schedule. Neither participants nor those delivering interventions were blinded, but those assessing outcomes were blinded to group assignment. Results All villages contacted agreed to participate and accepted randomisation. 36 women were recruited per village; 432 participants were randomised (IG n=216; CG n=216). No clusters were lost to follow-up. The main analysis included 86% (373/432) of participants, 90% (195/216) from the IG and 82% (178/216) from the CG. Conclusions Criteria related to feasibility were satisfied, giving us confidence that we can successfully conduct a larger cluster randomised trial. Methodological lessons will inform design of the main study. Trial registration number ISRCTN16703097 PMID:26384721
Thrust reverser design studies for an over-the-wing STOL transport
NASA Technical Reports Server (NTRS)
Ammer, R. C.; Sowers, H. D.
1977-01-01
Aerodynamic and acoustics analytical studies were conducted to evaluate three thrust reverser designs for potential use on commercial over-the-wing STOL transports. The concepts were: (1) integral D nozzle/target reverser, (2) integral D nozzle/top arc cascade reverser, and (3) post exit target reverser integral with wing. Aerodynamic flowpaths and kinematic arrangements for each concept were established to provide a 50% thrust reversal capability. Analytical aircraft stopping distance/noise trade studies conducted concurrently with flow path design showed that these high efficiency reverser concepts are employed at substantially reduced power settings to meet noise goals of 100 PNdB on a 152.4 m sideline and still meet 609.6 m landing runway length requirements. From an overall installation standpoint, only the integral D nozzle/target reverser concept was found to penalize nacelle cruise performance; for this concept a larger nacelle diameter was required to match engine cycle effective area demand in reverse thrust.
Wide Field Infra-Red Survey Telescope (WFIRST) 2.4-Meter Mission Study
NASA Technical Reports Server (NTRS)
Content, D.; Aaron, K.; Alplanalp, L.; Anderson, K.; Capps, R.; Chang, Z.; Dooley, J.; Egerman, R.; Goullioud, R.; Klein, D.;
2013-01-01
The most recent study of the Wide Field Infrared Survey Telescope (WFIRST) mission is based on reuse of an existing 2.4m telescope. This study was commissioned by NASA to examine the potential science return and cost effectiveness of WFIRST by using this significantly larger aperture telescope. We review the science program envisioned by the WFIRST 2012-2013 Science Definition Team (SDT), an overview of the mission concept, and the telescope design and status. Comparisons against the previous 1.3m and reduced cost 1.1m WFIRST design concepts are discussed. A significant departure from past point designs is the option for serviceability and the geostationary orbit location which enables servicing and replacement instrument insertion later during mission life. Other papers at this conference provide more in depth discussion of the wide field instrument and the optional exoplanet imaging coronagraph instrument.
Integration of Mirror Design with Suspension System using NASA's New Mirror Modeling Software
NASA Technical Reports Server (NTRS)
Arnold, William; Bevan Ryan M.; Stahl, Philip
2013-01-01
Advances in mirror fabrication is making very large space based telescopes possible. In the many applications, only monolithic mirrors meet the performance requirements. The existing and near-term planned heavy launch vehicles place a premium on lowest possible mass. Again, available and planned payload shroud size limits near term designs to 4 meter class mirror. Practical 8 meter and beyond designs could encourage planners to include larger shrouds if it can be proven that such mirrors can be manufactured. These two factors lower mass and larger mirrors, presents the classic optimization problem. There is a practical upper limit to how large a mirror can be supported by a purely kinematic mount system and be launched. This paper shows how the design of the suspension system and mirror blank needs to be designed simultaneously. We will also explore the concepts of auxiliary support systems, which act only during launch and disengage on orbit. We will define required characteristics of these systems and show how they can substantially reduce the mirror mass. The AMTD project is developing and maturing the processes for future replacements for HUBBLE, creating the design tools, validating the methods and techniques necessary to manufacture, test and launch extremely large optical missions. This paper will use the AMTD 4 meter "design point" as an illustration of the typical use of the modeler in generating the multiple models of mirror and suspension systems used during the conceptual design phase of most projects. The influence of Hexapod geometry, mirror depth, cell size and construction techniques (Exelsis Deep Core Low Temperature Fusion (c) versus Corning Frit Bonded (c) versus Schott Pocket Milled Zerodur (c) in this particular study) are being evaluated. Due to space and time consideration we will only be able to present snippets of the study in this paper. The advances in manufacturing techniques for lightweight mirrors, such as EXELSIS deep core low temperature fusion, Corning's continued improvements in the Frit bonding process and the ability to cast large complex designs, combined with water-jet and conventional diamond.
Safety and fitness electronic records system (SAFER) : master test plan
DOT National Transportation Integrated Search
2000-01-01
This report contains highway design informaiton that will help accomodate the needs and capability of older road users. Specifically, it contains the recommendaitons section of a larger report titled: Older Driver Highway Design Handbook (FHWA-RD-97-...
Set-Based Design: Fleet Architecture and Design 2030-2035
2017-12-01
choose any quantity between 250 - 350 HP for the final system design without suffering the same consequences in PBD. Figure 2 visually compares SBD... comparing the coverages in 2035 to those in 2017. This report does not advocate for a larger or smaller domain grid factor for overall fleet design , as...Distribution is unlimited. SET-BASED DESIGN : FLEET ARCHITECTURE AND DESIGN 2030–2035 by David Alessandria, Isa Al-Jawder, Eric Clow, Carlos
Mawjee, Karizma; Woltering, Steven; Lai, Nathan; Gotlieb, Howell; Kronitz, Reena; Tannock, Rosemary
2017-09-01
The aim of this study was to evaluate whether a shortened-length session of CogMed Working Memory Training (CWMT) would be a suitable active control group and evaluate study protocol to aid in design refinements for a larger randomized controlled trial (RCT). Thirty-eight post-secondary students diagnosed with ADHD were randomized into 25 sessions of standard (45 min/session) or shortened (15 min/session) CWMT, or into a waitlist control group. There was no significant difference in completion rate or training index score between the standard- and shortened-length groups indicating that both groups showed improvement and put forth good effort during training. Preliminary findings suggest that shorter training sessions may induce similar levels of engagement, motivation, and expectancy of improvement in participants. We conclude that a larger scale RCT that utilizes shortened-length training as an active control group is warranted, but that a few modifications to the study protocol will be required.
Multi-fuel rotary engine for general aviation aircraft
NASA Technical Reports Server (NTRS)
Jones, C.; Ellis, D. R.; Meng, P. R.
1983-01-01
Design studies of advanced multifuel general aviation and commuter aircraft rotary stratified charge engines are summarized. Conceptual design studies were performed at two levels of technology, an advanced general aviation engines sized to provide 186/250 shaft kW/hp under cruise conditions at 7620 (25,000 m/ft) altitude. A follow on study extended the results to larger (2500 hp max.) engine sizes suitable for applications such as commuter transports and helicopters. The study engine designs were derived from relevant engine development background including both prior and recent engine test results using direct injected unthrottled rotary engine technology. Aircraft studies, using these resultant growth engines, define anticipated system effects of the performance and power density improvements for both single engine and twin engine airplanes. The calculated results indicate superior system performance and 27 to 33 percent fuel economy improvement for the rotary engine airplanes as compared to equivalent airframe concept designs with current baseline engines. The research and technology activities required to attain the projected engine performance levels are also discussed. Previously announced in STAR as N83-18910
The design and construction of the CAD-1 airship
NASA Technical Reports Server (NTRS)
Kleiner, H. J.; Schneider, R.; Duncan, J. L.
1975-01-01
The background history, design philosophy and Computer application as related to the design of the envelope shape, stress calculations and flight trajectories of the CAD-1 airship, now under construction by Canadian Airship Development Corporation are reported. A three-phase proposal for future development of larger cargo carrying airships is included.
Environmental and Genetic Contributors to Hypospadias: A Review of the Epidemiologic Evidence
Carmichael, Suzan L.; Shaw, Gary M.; Lammer, Edward J.
2012-01-01
This review evaluates current knowledge related to trends in the prevalence of hypospadias, the association of hypospadias with endocrine-disrupting exposures, and the potential contribution of genetic susceptibility to its etiology. The review focuses on epidemiologic evidence. Increasing prevalence of hypospadias has been observed, but such increases tend to be localized to specific regions or time periods. Thus, generalized statements that hypospadias is increasing are unsupported. Due to limitations of study designs and inconsistent results, firm conclusions cannot be made regarding the association of endocrine-disrupting exposures with hypospadias. Studies with more rigorous study designs (e.g., larger and more detailed phenotypes) and exposure assessment that encompasses more breadth as well as depth (e.g., specific endocrine-related chemicals) will be critical to make better inferences about these important environmental exposures. Many candidate genes for hypospadias have been identified, but few of them have been examined to an extent that enables solid conclusions. Further studies are needed that include larger sample sizes, comparison groups that are more representative of the populations from which the cases were derived, phenotype-specific analyses, and more extensive exploration of variants. In conclusion, examining the associations of environmental and genetic factors with hypospadias remain important areas of inquiry, although our actual understanding of their contribution to hypospadias risk in humans is currently limited. PMID:22678668
Design and Performance Investigation for the Optical Combinational Networks at High Data Rate
NASA Astrophysics Data System (ADS)
Tripathi, Devendra Kr.
2017-05-01
This article explores performance study for optical combinational designs based on nonlinear characteristics with semiconductor optical amplifier (SOA). Two configurations for optical half-adder with non-return-to-zero modulation pattern altogether with Mach-Zehnder modulator, interferometer at 50-Gbps data rate have been successfully realized. Accordingly, SUM and CARRY outputs have been concurrently executed and verified for their output waveforms. Numerical simulations for variation of data rate and key design parameters have been effectively executed outcome with optimum performance. Investigations depict overall good performance of the design in terms of the extinction factor. It also inferred that all-optical realization based on SOA is competent scheme, as it circumvents costly optoelectronic translation. This could be well supportive to erect larger complex optical combinational circuits.
Design study of flat belt CVT for electric vehicles
NASA Technical Reports Server (NTRS)
Kumm, E. L.
1980-01-01
A continuously variable transmission (CVT) was studied, using a novel flat belt pulley arrangement which couples the high speed output shaft of an energy storage flywheel to the drive train of an electric vehicle. A specific CVT arrangement was recommended and its components were selected and sized, based on the design requirements of a 1700 KG vehicle. A design layout was prepared and engineering calculations made of component efficiencies and operating life. The transmission efficiency was calculated to be significantly over 90% with the expected vehicle operation. A design consistent with automotive practice for low future production costs was considered, together with maintainability. The technology advancements required to develop the flat belt CVT were identified and an estimate was made of how the size of the flat belt CVT scales to larger and smaller design output torques. The suitability of the flat belt CVT for alternate application to an electric vehicle powered by an electric motor without flywheel and to a hybrid electric vehicle powered by an electric motor with an internal combustion engine was studied.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Staller, G.E.; Hamilton, I.D.; Aker, M.F.
1978-02-01
A single-unit electron beam accelerator was designed, fabricated, and assembled in Sandia's Technical Area V to conduct magnetically insulated transmission experiments. Results of these experiments will be utilized in the future design of larger, more complex accelerators. This design makes optimum use of existing facilities and equipment. When designing new components, possible future applications were considered as well as compatibility with existing facilities and hardware.
1983-12-01
the output signal. As the number of coefficients increases (as n is made larger in the above equation ), a larger number of spectral peaks can be...kicij’Q,1. Im .6*.* . . ..f’ Hammett , J.C. (June 1979) Tactical commun ations-a precious resource (Student Essay). Carlisle Barracks, PA: U.S. Army War
Design and analysis of photonic crystal coupled cavity arrays for quantum simulation
NASA Astrophysics Data System (ADS)
Majumdar, Arka; Rundquist, Armand; Bajcsy, Michal; Dasika, Vaishno D.; Bank, Seth R.; Vučković, Jelena
2012-11-01
We performed an experimental study of coupled optical cavity arrays in a photonic crystal platform. We find that the coupling between the cavities is significantly larger than the fabrication-induced disorder in the cavity frequencies. Satisfying this condition is necessary for using such cavity arrays to generate strongly correlated photons, which has potential application in the quantum simulation of many-body systems.
Erik A. Lilleskov; Philip M. Wargo; Kristiina A. Vogt; Daniel J. Vogt
2008-01-01
Increased nitrogen (N) input has been found to alter ectomycorrhizal fungal communities over short deposition gradients and in fertilization experiments; however, its effects over larger spatial scales have not been determined. To address this gap, we reanalyzed data from a study originally designed to examine the effects of soil aluminum/calcium (Al/Ca) ratios on the...
ERIC Educational Resources Information Center
Burrell, Andrew; Beard, Roger
2018-01-01
There has been little research into how children use language play in writing. The unprompted language play of 36 children was investigated through their writing of a short advertisement. The sample comprised three attainment sub-groups from a larger repeat-design study of persuasive writing in the 9-11 age-range. The writing was analysed using…
ERIC Educational Resources Information Center
Borders, Tyrone F.; Aday, Lu Ann; Xu, Ke Tom
2004-01-01
As elderly people become a larger proportion of the rural population, it is important to identify those at risk for poor health. Predictors of health-related quality of life can be useful in designing interventions. Purpose: One objective of the present study was to profile the health-related quality of life of community-dwelling, elderly people…
ERIC Educational Resources Information Center
Vanderloo, Leigh M.; Tucker, Patricia
2017-01-01
Objective: To compare physical activity and sedentary time among young children whose schools adhere to traditional (i.e. three outdoor playtimes = 70 minutes) versus balanced day (i.e. two outdoor playtimes = ~55 minutes) schedules in Ontario full-day kindergarten classrooms. Design: The project was part of a larger, 2-year cross-sectional study.…
ERIC Educational Resources Information Center
Gustafson, Brenda; Mahaffy, Peter; Martin, Brian
2011-01-01
This article reports a subset of findings from a larger study centered on designing a series of six digital learning objects to help Grade 5 (age 10-12) students begin to consider the nature of models (understood as the physical or mental representation of objects, phenomena, or processes), the particle nature of matter, and the behavior of…
ERIC Educational Resources Information Center
Maxey, Phyllis F.
One of a series of units on business issues designed for secondary school students, this packet examines United States and Soviet trade within the context of worldwide economic and political associations. Introductory in nature, the 5-day unit is suitable for use by itself or as part of a larger study of comparative economic systems, American…
ERIC Educational Resources Information Center
Tsang, Edmund, Ed.
This volume, the 14th in a series of monographs on service learning and academic disciplinary areas, is designed as a practical guide for faculty seeking to integrate service learning into an engineering course. The volume also deals with larger issues in engineering education and provides case studies of service-learning courses. The articles…
ERIC Educational Resources Information Center
Edwards, D. Brent, Jr.; Okitsu, Taeko; da Costa, Romina; Kitamura, Yuto
2017-01-01
This research note shares insights which resulted from a larger study into the ways in which the United Nations Educational, Scientific and Cultural Organization (UNESCO)--during 2010-2014--used its position as coordinator of the post-Dakar Framework for Action (initiated at the World Education Forum held in 2000 and designed to reinvigorate the…
Partially filled electrodes for digital microfluidic devices
NASA Astrophysics Data System (ADS)
Pyne, D. G.; Salman, W. M.; Abdelgawad, M.; Sun, Y.
2013-07-01
As digital microfluidics technology evolves, the need for integrating additional elements (e.g., sensing/detection and heating elements) on the electrode increases. Consequently, electrode area for droplet actuation is reduced to create space for accommodating these additional elements, which undesirably affects force generation. Electrodes cannot simply be scaled larger to compensate for this loss of force, as this would also increase droplet volume and thereby compromise the advantages thought in miniaturization. Here, we present a study evaluating, numerically with preliminary experimental verification, different partially filled electrode designs and suggesting designs that combine high actuation forces with a large reduction in electrode area.
Thermal behavior of an experimental 2.5-kWh lithium/iron sulfide battery
NASA Astrophysics Data System (ADS)
Chen, C. C.; Olszanski, T. W.; Gibbard, H. F.
1981-10-01
The thermal energy generation and the gross thermal energy balance in the battery systems was studied. High temperature lithium/iron sulfide batteries for electric vehicle applications were developed. The preferred battery temperature range during operation and idle periods is 400 to 500 C. Thermal management is an essential part of battery design, the battery requires a thermal insulation vessel to minimize heat loss and heating and cooling systems to control temperature. Results of temperature measurements performed on a 2.5-kWh battery module, which was built to gain information for the design of larger systems are reported.
Marshall, M.R.; Diefenbach, D.R.; Wood, L.A.; Cooper, R.J.
2004-01-01
Many species of bird exhibit varying degrees of site-fidelity to the previous year's territory or breeding area, a phenomenon we refer to as incomplete breeding site-fidelity. If the territory they occupy is located beyond the bounds of the study area or search area (i.e., they have emigrated from the study area), the bird will go undetected and is therefore indistinguishable from dead individuals in capture-mark-recapture studies. Differential emigration rates confound inferences regarding differences in survival between sexes and among species if apparent survival rates are used as estimates of true survival. Moreover, the bias introduced by using apparent survival rates for true survival rates can have profound effects on the predictions of population persistence through time, source/sink dynamics, and other aspects of life-history theory. We investigated four study design and analysis approaches that result in apparent survival estimates that are closer to true survival estimates. Our motivation for this research stemmed from a multi-year capture-recapture study of Prothonotary Warblers (Protonotaria citrea) on multiple study plots within a larger landscape of suitable breeding habitat where substantial inter-annual movements of marked individuals among neighboring study plots was documented. We wished to quantify the effects of this type of movement on annual survival estimation. The first two study designs we investigated involved marking birds in a core area and resighting them in the core as well as an area surrounding the core. For the first of these two designs, we demonstrated that as the resighting area surrounding the core gets progressively larger, and more "emigrants" are resighted, apparent survival estimates begin to approximate true survival rates (bias < 0.01). However, given observed inter-annual movements of birds, it is likely to be logistically impractical to resight birds on sufficiently large surrounding areas to minimize bias. Therefore, as an alternative protocol, we analyzed the data with subsets of three progressively larger areas surrounding the core. The data subsets provided four estimates of apparent survival that asymptotically approached true survival. This study design and analytical approach is likely to be logistically feasible in field settings and yields estimates of true survival unbiased (bias < 0.03) by incomplete breeding site-fidelity over a range of inter-annual territory movement patterns. The third approach we investigated used a robust design data collection and analysis approach. This approach resulted in estimates of survival that were unbiased (bias < 0.02), but were very imprecise and likely would not yield reliable estimates in field situations. The fourth approach utilized a fixed study area size, but modeled detection probability as a function of bird proximity to the study plot boundary (e.g., those birds closest to the edge are more likely to emigrate). This approach also resulted in estimates of survival that were unbiased (bias < 0.02), but because the individual covariates were normalized, the average capture probability was 0.50, and thus did not provide an accurate estimate of the true capture probability. Our results show that the core-area with surrounding resight-only can provide estimates of survival that are not biased by the effects of incomplete breeding site-fidelity. ?? 2004 Museu de Cie??ncies Naturals.
Hybrid bilayer plasmonic metasurface efficiently manipulates visible light.
Qin, Fei; Ding, Lu; Zhang, Lei; Monticone, Francesco; Chum, Chan Choy; Deng, Jie; Mei, Shengtao; Li, Ying; Teng, Jinghua; Hong, Minghui; Zhang, Shuang; Alù, Andrea; Qiu, Cheng-Wei
2016-01-01
Metasurfaces operating in the cross-polarization scheme have shown an interesting degree of control over the wavefront of transmitted light. Nevertheless, their inherently low efficiency in visible light raises certain concerns for practical applications. Without sacrificing the ultrathin flat design, we propose a bilayer plasmonic metasurface operating at visible frequencies, obtained by coupling a nanoantenna-based metasurface with its complementary Babinet-inverted copy. By breaking the radiation symmetry because of the finite, yet small, thickness of the proposed structure and benefitting from properly tailored intra- and interlayer couplings, such coupled bilayer metasurface experimentally yields a conversion efficiency of 17%, significantly larger than that of earlier single-layer designs, as well as an extinction ratio larger than 0 dB, meaning that anomalous refraction dominates the transmission response. Our finding shows that metallic metasurface can counterintuitively manipulate the visible light as efficiently as dielectric metasurface (~20% in conversion efficiency in Lin et al.'s study), although the metal's ohmic loss is much higher than dielectrics. Our hybrid bilayer design, still being ultrathin (~λ/6), is found to obey generalized Snell's law even in the presence of strong couplings. It is capable of efficiently manipulating visible light over a broad bandwidth and can be realized with a facile one-step nanofabrication process.
Hybrid bilayer plasmonic metasurface efficiently manipulates visible light
Qin, Fei; Ding, Lu; Zhang, Lei; Monticone, Francesco; Chum, Chan Choy; Deng, Jie; Mei, Shengtao; Li, Ying; Teng, Jinghua; Hong, Minghui; Zhang, Shuang; Alù, Andrea; Qiu, Cheng-Wei
2016-01-01
Metasurfaces operating in the cross-polarization scheme have shown an interesting degree of control over the wavefront of transmitted light. Nevertheless, their inherently low efficiency in visible light raises certain concerns for practical applications. Without sacrificing the ultrathin flat design, we propose a bilayer plasmonic metasurface operating at visible frequencies, obtained by coupling a nanoantenna-based metasurface with its complementary Babinet-inverted copy. By breaking the radiation symmetry because of the finite, yet small, thickness of the proposed structure and benefitting from properly tailored intra- and interlayer couplings, such coupled bilayer metasurface experimentally yields a conversion efficiency of 17%, significantly larger than that of earlier single-layer designs, as well as an extinction ratio larger than 0 dB, meaning that anomalous refraction dominates the transmission response. Our finding shows that metallic metasurface can counterintuitively manipulate the visible light as efficiently as dielectric metasurface (~20% in conversion efficiency in Lin et al.’s study), although the metal’s ohmic loss is much higher than dielectrics. Our hybrid bilayer design, still being ultrathin (~λ/6), is found to obey generalized Snell’s law even in the presence of strong couplings. It is capable of efficiently manipulating visible light over a broad bandwidth and can be realized with a facile one-step nanofabrication process. PMID:26767195
CFL3D, FUN3d, and NSU3D Contributions to the Fifth Drag Prediction Workshop
NASA Technical Reports Server (NTRS)
Park, Michael A.; Laflin, Kelly R.; Chaffin, Mark S.; Powell, Nicholas; Levy, David W.
2013-01-01
Results presented at the Fifth Drag Prediction Workshop using CFL3D, FUN3D, and NSU3D are described. These are calculations on the workshop provided grids and drag adapted grids. The NSU3D results have been updated to reflect an improvement to skin friction calculation on skewed grids. FUN3D results generated after the workshop are included for custom participant generated grids and a grid from a previous workshop. Uniform grid refinement at the design condition shows a tight grouping in calculated drag, where the variation in the pressure component of drag is larger than the skin friction component. At this design condition, A fine-grid drag value was predicted with a smaller drag adjoint adapted grid via tetrahedral adaption to a metric and mixed-element subdivision. The buffet study produced larger variation than the design case, which is attributed to large differences in the predicted side-of-body separation extent. Various modeling and discretization approaches had a strong impact on predicted side-of-body separation. This large wing root separation bubble was not observed in wind tunnel tests indicating that more work is necessary in modeling wing root juncture flows to predict experiments.
A Model for Student Video Production.
ERIC Educational Resources Information Center
Adams, Dennis M.
1988-01-01
Duties of a video design team include writing, storyboard designing, directing, lighting, shooting, taping, and editing. As few as two students can handle these tasks; for larger productions, students can work in various capacities by serving as crew for each other. (JOW)
Cogging Torque Reduction in a Permanent Magnet Wind Turbine Generator: Preprint
DOE Office of Scientific and Technical Information (OSTI.GOV)
Muljadi, E.; Green, J.
2002-01-01
In this paper, we investigate three design options to minimize cogging torque: uniformity of air gap, pole width, and skewing. Although the design improvement is intended for small wind turbines, it is also applicable to larger wind turbines.
Explanatory Versus Pragmatic Trials: An Essential Concept in Study Design and Interpretation.
Merali, Zamir; Wilson, Jefferson R
2017-11-01
Randomized clinical trials often represent the highest level of clinical evidence available to evaluate the efficacy of an intervention in clinical medicine. Although the process of randomization serves to maximize internal validity, the external validity, or generalizability, of such studies depends on several factors determined at the design phase of the trial including eligibility criteria, study setting, and outcomes of interest. In general, explanatory trials are optimized to demonstrate the efficacy of an intervention in a highly selected patient group; however, findings from these studies may not be generalizable to the larger clinical problem. In contrast, pragmatic trials attempt to understand the real-world benefit of an intervention by incorporating design elements that allow for greater generalizability and clinical applicability of study results. In this article we describe the explanatory-pragmatic continuum for clinical trials in greater detail. Further, a well-accepted tool for grading trials on this continuum is described, and applied, to 2 recently published trials pertaining to the surgical management of lumbar degenerative spondylolisthesis.
NASA Astrophysics Data System (ADS)
Fang, L.
2014-12-01
The analysis in the impact of transition zone on the optical performance of human eye after laser refractive surgery is important for improving visual correction technology. By designing the ablation profiles of aspheric transition zone and creating the ablation profile for conventional refractive surgery in optical zone, the influence of aspheric transition zone on residual aberrations was studied. The results indicated that the ablation profiles of transition zone had a significant influence on the residual wavefront aberrations. For a hyperopia correction, the profile #9 shows a larger induced coma and spherical aberration when the translation of the centre of pupil remains constant. However, for a myopia astigmatism correction, the induced coma and spherical aberration in profile #1 shows relatively larger RMS values than those in other profiles. Therefore, the residual higher order aberrations may be decreased by optimizing ablation profiles of transition zone, but they cannot be eliminated. In order to achieve the best visual performance, the design of ablation pattern of transition zone played a crucial role.
Sterically allowed configuration space for amino acid dipeptides
NASA Astrophysics Data System (ADS)
Caballero, Diego; Maatta, Jukka; Sammalkorpi, Maria; O'Hern, Corey; Regan, Lynne
2014-03-01
Despite recent improvements in computational methods for protein design, we still lack a quantitative, predictive understanding of the intrinsic propensities for amino acids to be in particular backbone or side-chain conformations. This question has remained unsettled for years because of the discrepancies between different experimental approaches. To address it, I performed all-atom hard-sphere simulations of hydrophobic residues with stereo-chemical constraints and non-attractive steric interactions between non-bonded atoms for ALA, ILE, LEU and VAL dipeptide mimetics. For these hard-sphere MD simulations, I show that transitions between α-helix and β-sheet structures only occur when the bond angle τ(N -Cα - C) >110° , and the probability distribution of bond angles for structures in the `bridge' region of ϕ- ψ space is shifted to larger angles compared to that in other regions. In contrast, the relevant bond-angle distributions obtained from most molecular dynamics packages are broader and shifter to larger values. I encounter similar correlations between bond angles and side-chain dihedral angles. The success of these studies is an argument for re-incorporating local stereochemical constraints into computational protein design methodology.
Biogasification products of water hyacinth wastewater reclamation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chynoweth, D.P.; Biljetina, R.; Srivastava, V.J.
1984-01-01
This paper describes the results of research in progress to evaluate the use of water hyacinth for wastewater treatment and subsequent conversion of hyacinth and sludge to methane by anaerobic digestion. Laboratory studies have been directed toward evaluating advanced biogasification concepts and establishing a data base for the design and operation of an experimental test unit (ETU) located at the water hyacinth wastewater treatment facility at Walt Disney World (WDW) located in Kissimmee, Florida. Laboratory-scale kinetic experiments have been conducted using continuously-stirred tank reactors (CSTR) and a novel non-mixed upflow solids reactor (USR) receiving a hyacinth/sludge blend at retention timesmore » of 15 down to 2.1 days. The data suggest that best performance is achieved in the USR which has longer solids and organism retention. A larger-scale ETU (160 cu ft) was designed and installed at WDW in 1983 and started up in 1984. The purpose of this unit is to validate laboratory experiments and to evaluate larger-scale equipment used for chopping, slurry preparation, mixing, and effluent dewatering. The ETU includes a front end designed for multiple feed processing and storage, a fully instrumented USR digester, and tanks for effluent and gas storage. The ETU is currently being operated on a 2:1 blend (dry wt basis) of water hyacinth and primary sludge. Performance is good without major operational problems. Results of laboratory studies and start-up and operation of the ETU will be presented. 7 references, 4 figures, 1 table.« less
Development of Cold-Formed Steel Seismic Design Recommendations
2015-08-01
applied loads, so the impact on design would be minimal. However, had the test been carried out to larger panel deformations without loss of capacity... test shear panels and development of preliminary design recommendations 6. Definition of material properties and coupon test results 7. Pretest of...predicted panel response based on preliminary design model and coupon test results 8. Definition of test configuration, procedures, and
Smith, Jennifer L.; Sturrock, Hugh J. W.; Assefa, Liya; Nikolay, Birgit; Njenga, Sammy M.; Kihara, Jimmy; Mwandawiro, Charles S.; Brooker, Simon J.
2015-01-01
Transmission assessment surveys (TAS) for lymphatic filariasis have been proposed as a platform to assess the impact of mass drug administration (MDA) on soil-transmitted helminths (STHs). This study used computer simulation and field data from pre- and post-MDA settings across Kenya to evaluate the performance and cost-effectiveness of the TAS design for STH assessment compared with alternative survey designs. Variations in the TAS design and different sample sizes and diagnostic methods were also evaluated. The district-level TAS design correctly classified more districts compared with standard STH designs in pre-MDA settings. Aggregating districts into larger evaluation units in a TAS design decreased performance, whereas age group sampled and sample size had minimal impact. The low diagnostic sensitivity of Kato-Katz and mini-FLOTAC methods was found to increase misclassification. We recommend using a district-level TAS among children 8–10 years of age to assess STH but suggest that key consideration is given to evaluation unit size. PMID:25487730
Paired split-plot designs of multireader multicase studies.
Chen, Weijie; Gong, Qi; Gallas, Brandon D
2018-07-01
The widely used multireader multicase ROC study design for comparing imaging modalities is the fully crossed (FC) design: every reader reads every case of both modalities. We investigate paired split-plot (PSP) designs that may allow for reduced cost and increased flexibility compared with the FC design. In the PSP design, case images from two modalities are read by the same readers, thereby the readings are paired across modalities. However, within each modality, not every reader reads every case. Instead, both the readers and the cases are partitioned into a fixed number of groups and each group of readers reads its own group of cases-a split-plot design. Using a [Formula: see text]-statistic based variance analysis for AUC (i.e., area under the ROC curve), we show analytically that precision can be gained by the PSP design as compared with the FC design with the same number of readers and readings. Equivalently, we show that the PSP design can achieve the same statistical power as the FC design with a reduced number of readings. The trade-off for the increased precision in the PSP design is the cost of collecting a larger number of truth-verified patient cases than the FC design. This means that one can trade-off between different sources of cost and choose a least burdensome design. We provide a validation study to show the iMRMC software can be reliably used for analyzing data from both FC and PSP designs. Finally, we demonstrate the advantages of the PSP design with a reader study comparing full-field digital mammography with screen-film mammography.
The benefits of yoga for women veterans with chronic low back pain.
Groessl, Erik J; Weingart, Kimberly R; Johnson, Neil; Baxi, Sunita
2012-09-01
Chronic low back (CLBP) pain is prevalent among military veterans and often leads to functional limitations, psychologic symptoms, lower quality of life, and higher health care costs. An increasing proportion of U.S. veterans are women, and women veterans may have different health care needs than men veterans. The purpose of this study was to assess the impact of a yoga intervention on women and men with CLBP. SUBJECTS/SETTING/INTERVENTION: VA patients with CLBP were referred by primary care providers to a clinical yoga program. Research participants completed a brief battery of questionnaires before their first yoga class and again 10 weeks later in a single-group, pre-post study design. Questionnaires included measures of pain (Pain Severity Scale), depression (CESD-10), energy/fatigue, and health-related quality of life (SF-12). Yoga attendance and home practice of yoga were also measured. Repeated-measures analysis of variance was used to analyze group differences over time while controlling for baseline differences. The 53 participants who completed both assessments had a mean age of 53 years, and were well educated, 41% nonwhite, 49% married, and had varying employment status. Women participants had significantly larger decreases in depression (p=0.046) and pain "on average" (p=0.050), and larger increases in energy (p=0.034) and SF-12 Mental Health (p=0.044) than men who participated. The groups did not differ significantly on yoga attendance or home practice of yoga. These results suggest that women veterans may benefit more than men veterans from yoga interventions for chronic back pain. Conclusions are tentative because of the small sample size and quasi-experimental study design. A more rigorous study is being designed to answer these research questions more definitively.
Using Mathematical Modeling and Set-Based Design Principles to Recommend an Existing CVL Design
2017-09-01
designs, it would be worth researching the feasibility of varying the launch method on some of the larger light aircraft carriers, such as the Liaoning...thesis examines the trade space in major design areas such as tonnage, aircraft launch method , propulsion, and performance in order to illustrate...future conflict. This thesis examines the trade space in major design areas such as tonnage, aircraft launch method , propulsion, and performance in
Effects Of Methylphenidate And Morphine On Delay-Discount Functions Obtained Within Sessions
Pitts, Raymond C; McKinney, A. Patrick
2005-01-01
Four rats responded under a “self-control” procedure designed to obtain delay-discount functions within sessions. Each session consisted of seven blocks, with seven trials within each block. Each block consisted of two initial forced-choice trials followed by five free-choice trials. On choice trials, the rats could press either of two retractable levers. A press on one lever was followed by presentation of a smaller reinforcer (a single dipper presentation of a sucrose solution); a press on the other lever was followed by presentation of a larger reinforcer (four consecutive dipper presentations). The delay associated with the smaller reinforcer always was 0 s, whereas the signaled delay associated with the larger reinforcer increased across blocks (from 0 to 50 s). Under these conditions, the percentage of choices of the larger reinforcer decreased across blocks, and relatively reliable delay-discount functions were obtained within sessions. Doses of methylphenidate (1.0 to 17.0 mg/kg) and morphine (0.3 to 17.0 mg/kg) were then administered prior to selected sessions. Typically, intermediate doses of methylphenidate shifted the discount functions to the right (increased choices of the larger reinforcer). For 2 of the rats, this effect was pronounced; for the other 2 rats, this effect occurred after the range of delays for the larger reinforcer was decreased (0 to 20 s). On the other hand, in most cases morphine produced a slight leftward shift in the discount function (decreased choices of the larger reinforcer). The present procedure appears to be a useful and efficient method to characterize drug effects on an entire delay-discount function. As with many procedures used to study self-control choices, however, sources of control other than reinforcement delay and amount may have been operating in the present study, and these sources must be considered when interpreting drug effects. PMID:16047609
Tandogan, Tamer; Auffarth, Gerd U; Choi, Chul Y; Liebing, Stephanie; Mayer, Christian; Khoramnia, Ramin
2017-02-08
To analyse objective optical properties of the spherical and aspheric design of the same intraocular lens (IOL) model using optical bench analysis. This study entailed a comparative analysis of 10 spherical C-flex 570 C and 10 aspheric C-flex 970 C IOLs (Rayner Intraocular Lenses Ltd., Hove, UK) of 26 diopters [D] using an optical bench (OptiSpheric, Trioptics, Germany). In all lenses, we evaluated the modulation transfer function (MTF) at 50 lp/mm and 100 lp/mm and the Strehl Ratio using a 3-mm (photopic) and 4.5-mm (mesopic) aperture. At 50 lp/mm, the MTF values were 0.713/0.805 (C-flex 570 C/C-flex 970 C) for a 3-mm aperture and 0.294/0.591 for a 4.5-mm aperture. At 100 lp/mm, the MTF values were 0.524/0.634 for a 3-mm aperture and 0.198/0.344 for a 4.5-mm aperture. The Strehl Ratio was 0.806/0.925 and 0.237/0.479 for a 3-mm and 4.5-mm aperture respectively. A Mann-Whitney U test revealed all intergroup differences to be statistically significant (p < 0.01). The aspheric IOL design achieved higher MTF values than the spherical design of the same IOL for both apertures. Moreover, the differences between the two designs of the IOL were more prominent for larger apertures. This suggests that the evaluated IOL provides enhanced optical quality to patients with larger pupils or working under mesopic conditions.
7 CFR 1755.902 - Minimum performance Specification for fiber optic cables.
Code of Federal Regulations, 2012 CFR
2012-01-01
... such a way as to form a cylindrical group. (2) The standard cylindrical group or core designs commonly consist of 4, 6, 12, 18, or 24 fibers. Cylindrical groups or core designs larger than the sizes shown...) Inner jackets. (1) For designs with more than one jacket, the inner jackets must be applied directly...
7 CFR 1755.902 - Minimum performance Specification for fiber optic cables.
Code of Federal Regulations, 2011 CFR
2011-01-01
... such a way as to form a cylindrical group. (2) The standard cylindrical group or core designs commonly consist of 4, 6, 12, 18, or 24 fibers. Cylindrical groups or core designs larger than the sizes shown...) Inner jackets. (1) For designs with more than one jacket, the inner jackets must be applied directly...
7 CFR 1755.902 - Minimum performance Specification for fiber optic cables.
Code of Federal Regulations, 2014 CFR
2014-01-01
... such a way as to form a cylindrical group. (2) The standard cylindrical group or core designs commonly consist of 4, 6, 12, 18, or 24 fibers. Cylindrical groups or core designs larger than the sizes shown...) Inner jackets. (1) For designs with more than one jacket, the inner jackets must be applied directly...
7 CFR 1755.902 - Minimum performance Specification for fiber optic cables.
Code of Federal Regulations, 2010 CFR
2010-01-01
... such a way as to form a cylindrical group. (2) The standard cylindrical group or core designs commonly consist of 4, 6, 12, 18, or 24 fibers. Cylindrical groups or core designs larger than the sizes shown...) Inner jackets. (1) For designs with more than one jacket, the inner jackets must be applied directly...
7 CFR 1755.902 - Minimum performance Specification for fiber optic cables.
Code of Federal Regulations, 2013 CFR
2013-01-01
... such a way as to form a cylindrical group. (2) The standard cylindrical group or core designs commonly consist of 4, 6, 12, 18, or 24 fibers. Cylindrical groups or core designs larger than the sizes shown...) Inner jackets. (1) For designs with more than one jacket, the inner jackets must be applied directly...
Space Human Factors: Research to Application
NASA Technical Reports Server (NTRS)
Woolford, Barbara
2008-01-01
Human Factors has been instrumental in preventing potential on-orbit hazards and increasing overall crew safety. Poor performance & operational learning curves on-orbit are mitigated. Human-centered design is applied to optimize design and minimize potentially hazardous conditions, especially with larger crew sizes and habitat constraints. Lunar and Mars requirements and design developments are enhanced, based on ISS Lessons Learned.
Development of a new-generation active falling sphere
NASA Technical Reports Server (NTRS)
Croskey, C. L.; Mitchell, J. D.; Schiano, J. L.; Kenkre, N. V.; Cresci, D. J.
1997-01-01
A new generation falling sphere, designed to measure winds and temperatures, is described. This sphere combines nanotechnology accelerometers and GaAs radiofrequency transmitters in a 100 g to 150 g package. This new instrumentation can be added to the standard inflatable sphere launched by a rocket or separately deployed from a larger rocket in which it is carried as part of a much larger scientific instrument package.
NASA Astrophysics Data System (ADS)
Velazquez, Antonio; Swartz, Raymond A.
2011-04-01
Wind turbine systems are attracting considerable attention due to concerns regarding global energy consumption as well as sustainability. Advances in wind turbine technology promote the tendency to improve efficiency in the structure that support and produce this renewable power source, tending toward more slender and larger towers, larger gear boxes, and larger, lighter blades. The structural design optimization process must account for uncertainties and nonlinear effects (such as wind-induced vibrations, unmeasured disturbances, and material and geometric variabilities). In this study, a probabilistic monitoring approach is developed that measures the response of the turbine tower to stochastic loading, estimates peak demand, and structural resistance (in terms of serviceability). The proposed monitoring system can provide a real-time estimate of the probability of exceedance of design serviceability conditions based on data collected in-situ. Special attention is paid to wind and aerodynamic characteristics that are intrinsically present (although sometimes neglected in health monitoring analysis) and derived from observations or experiments. In particular, little attention has been devoted to buffeting, usually non-catastrophic but directly impacting the serviceability of the operating wind turbine. As a result, modal-based analysis methods for the study and derivation of flutter instability, and buffeting response, have been successfully applied to the assessment of the susceptibility of high-rise slender structures, including wind turbine towers. A detailed finite element model has been developed to generate data (calibrated to published experimental and analytical results). Risk assessment is performed for the effects of along wind forces in a framework of quantitative risk analysis. Both structural resistance and wind load demands were considered probabilistic with the latter assessed by dynamic analyses.
Ban, Jong-Wook; Emparanza, José Ignacio; Urreta, Iratxe; Burls, Amanda
2016-01-01
Background Many new clinical prediction rules are derived and validated. But the design and reporting quality of clinical prediction research has been less than optimal. We aimed to assess whether design characteristics of validation studies were associated with the overestimation of clinical prediction rules’ performance. We also aimed to evaluate whether validation studies clearly reported important methodological characteristics. Methods Electronic databases were searched for systematic reviews of clinical prediction rule studies published between 2006 and 2010. Data were extracted from the eligible validation studies included in the systematic reviews. A meta-analytic meta-epidemiological approach was used to assess the influence of design characteristics on predictive performance. From each validation study, it was assessed whether 7 design and 7 reporting characteristics were properly described. Results A total of 287 validation studies of clinical prediction rule were collected from 15 systematic reviews (31 meta-analyses). Validation studies using case-control design produced a summary diagnostic odds ratio (DOR) 2.2 times (95% CI: 1.2–4.3) larger than validation studies using cohort design and unclear design. When differential verification was used, the summary DOR was overestimated by twofold (95% CI: 1.2 -3.1) compared to complete, partial and unclear verification. The summary RDOR of validation studies with inadequate sample size was 1.9 (95% CI: 1.2 -3.1) compared to studies with adequate sample size. Study site, reliability, and clinical prediction rule was adequately described in 10.1%, 9.4%, and 7.0% of validation studies respectively. Conclusion Validation studies with design shortcomings may overestimate the performance of clinical prediction rules. The quality of reporting among studies validating clinical prediction rules needs to be improved. PMID:26730980
Ban, Jong-Wook; Emparanza, José Ignacio; Urreta, Iratxe; Burls, Amanda
2016-01-01
Many new clinical prediction rules are derived and validated. But the design and reporting quality of clinical prediction research has been less than optimal. We aimed to assess whether design characteristics of validation studies were associated with the overestimation of clinical prediction rules' performance. We also aimed to evaluate whether validation studies clearly reported important methodological characteristics. Electronic databases were searched for systematic reviews of clinical prediction rule studies published between 2006 and 2010. Data were extracted from the eligible validation studies included in the systematic reviews. A meta-analytic meta-epidemiological approach was used to assess the influence of design characteristics on predictive performance. From each validation study, it was assessed whether 7 design and 7 reporting characteristics were properly described. A total of 287 validation studies of clinical prediction rule were collected from 15 systematic reviews (31 meta-analyses). Validation studies using case-control design produced a summary diagnostic odds ratio (DOR) 2.2 times (95% CI: 1.2-4.3) larger than validation studies using cohort design and unclear design. When differential verification was used, the summary DOR was overestimated by twofold (95% CI: 1.2 -3.1) compared to complete, partial and unclear verification. The summary RDOR of validation studies with inadequate sample size was 1.9 (95% CI: 1.2 -3.1) compared to studies with adequate sample size. Study site, reliability, and clinical prediction rule was adequately described in 10.1%, 9.4%, and 7.0% of validation studies respectively. Validation studies with design shortcomings may overestimate the performance of clinical prediction rules. The quality of reporting among studies validating clinical prediction rules needs to be improved.
High intensity multi beam design of SANS instrument for Dhruva reactor
DOE Office of Scientific and Technical Information (OSTI.GOV)
Abbas, Sohrab, E-mail: abbas@barc.gov.in; Aswal, V. K.; Désert, S.
A new and versatile design of Small Angle Neutron Scattering (SANS) instrument based on utilization of multi-beam is presented. The multi-pinholes and multi-slits as SANS collimator for medium flux Dhruva rearctor have been proposed and their designs have been validated using McStas simulations. Various instrument configurations to achieve different minimum wave vector transfers in scattering experiments are envisioned. These options enable smooth access to minimum wave vector transfers as low as ~ 6×10{sup −4} Å{sup −1} with a significant improvement in neutron intensity, allowing faster measurements. Such angularly well defined and intense neutron beam will allow faster SANS studies ofmore » agglomerates larger than few tens of nm.« less
Solar energy for process heat: Design/cost studies of four industrial retrofit applications
NASA Technical Reports Server (NTRS)
French, R. L.; Bartera, R. E.
1978-01-01
Five specific California plants with potentially attractive solar applications were identified in a process heat survey. These five plants were visited, process requirements evaluated, and conceptual solar system designs were generated. Four DOE (ERDA) sponsored solar energy system demonstration projects were also reviewed and compared to the design/cost cases included in this report. In four of the five cases investigated, retrofit installations providing significant amounts of thermal energy were found to be feasible. The fifth was rejected because of the condition of the building involved, but the process (soap making) appears to be an attractive potential solar application. Costs, however, tend to be high. Several potential areas for cost reduction were identified including larger collector modules and higher duty cycles.
New quantum codes constructed from quaternary BCH codes
NASA Astrophysics Data System (ADS)
Xu, Gen; Li, Ruihu; Guo, Luobin; Ma, Yuena
2016-10-01
In this paper, we firstly study construction of new quantum error-correcting codes (QECCs) from three classes of quaternary imprimitive BCH codes. As a result, the improved maximal designed distance of these narrow-sense imprimitive Hermitian dual-containing quaternary BCH codes are determined to be much larger than the result given according to Aly et al. (IEEE Trans Inf Theory 53:1183-1188, 2007) for each different code length. Thus, families of new QECCs are newly obtained, and the constructed QECCs have larger distance than those in the previous literature. Secondly, we apply a combinatorial construction to the imprimitive BCH codes with their corresponding primitive counterpart and construct many new linear quantum codes with good parameters, some of which have parameters exceeding the finite Gilbert-Varshamov bound for linear quantum codes.
Topological insulators double perovskites: A2TePoO6 (A = Ca, Sr, Ba)
NASA Astrophysics Data System (ADS)
Lee, Po-Han; Zhou, Jian; Pi, Shu-Ting; Wang, Yin-Kuo
2017-12-01
Based on first-principle calculations and direct density functional theory calculations of surface bands, we predict a new class of three-dimensional (3D) Z2 topological insulators (TIs) with larger bulk bandgaps up to 0.4 eV in double perovskite materials A2TePoO6 (A = Ca, Sr, and Ba). The larger nontrivial gaps are induced by the symmetry-protected band contact along with band inversion occurring in the absence of spin-orbit coupling (SOC) making the SOC more effective than conventional TIs. The proposed materials are chemically inert and more robust to surface perturbations due to its intrinsic protection layer. This study provides the double perovskite material as a rich platform to design new TI-based electronic devices.
Muñoz, Enrique
2015-01-01
We compare the results obtained from searching a smaller library thoroughly versus searching a more diverse, larger library sparsely. We study protein evolution with reduced amino acid alphabets, by simulating directed evolution experiments at three different alphabet sizes: 20, 5 and 2. We employ a physical model for evolution, the generalized NK model, that has proved successful in modeling protein evolution, antibody evolution, and T cell selection. We find that antibodies with higher affinity are found by searching a library with a larger alphabet sparsely than by searching a smaller library thoroughly, even with well-designed reduced libraries. We find ranked amino acid usage frequencies in agreement with observations of the CDR-H3 variable region of human antibodies. PMID:18375453
DOE Office of Scientific and Technical Information (OSTI.GOV)
Aiken, George
This document is the final technical report for a project designed to address fundamental processes controlling the release of mercury from flood plain soils associated with East Fork Poplar Creek, Tennessee near the U.S. Department of Energy Oak Ridge facility. The report summarizes the activities, findings, presentations, and publications resulting from an award to the U.S. Geological that were part of a larger overall effort including Kathy Nagy (University of Illinois, Chicago, Ill) and Joseph Ryan (University of Colorado, Boulder, CO). The specific charge for the U.S.G.S. portion of the study was to provide analytical support for the larger groupmore » effort (Nagy and Ryan), especially with regard to analyses of Hg and dissolved organic matter, and to provide information about the release of mercury from the floodplain soils.« less
Konetzka, R Tamara; Skira, Meghan M; Werner, Rachel M
2018-01-01
Pay-for-performance (P4P) programs have become a popular policy tool aimed at improving health care quality. We analyze how incentive design affects quality improvements in the nursing home setting, where several state Medicaid agencies have implemented P4P programs that vary in incentive structure. Using the Minimum Data Set and the Online Survey, Certification, and Reporting data from 2001 to 2009, we examine how the weights put on various performance measures that are tied to P4P bonuses, such as clinical outcomes, inspection deficiencies, and staffing levels, affect improvements in those measures. We find larger weights on clinical outcomes often lead to larger improvements, but small weights can lead to no improvement or worsening of some clinical outcomes. We find a qualifier for P4P eligibility based on having few or no severe inspection deficiencies is more effective at decreasing inspection deficiencies than using weights, suggesting simple rules for participation may incent larger improvement.
Konetzka, R. Tamara; Skira, Meghan M.; Werner, Rachel M.
2017-01-01
Pay-for-performance (P4P) programs have become a popular policy tool aimed at improving health care quality. We analyze how incentive design affects quality improvements in the nursing home setting, where several state Medicaid agencies have implemented P4P programs that vary in incentive structure. Using the Minimum Data Set and the Online Survey, Certification, and Reporting data from 2001 to 2009, we examine how the weights put on various performance measures that are tied to P4P bonuses, such as clinical outcomes, inspection deficiencies, and staffing levels, affect improvements in those measures. We find larger weights on clinical outcomes often lead to larger improvements, but small weights can lead to no improvement or worsening of some clinical outcomes. We find a qualifier for P4P eligibility based on having few or no severe inspection deficiencies is more effective at decreasing inspection deficiencies than using weights, suggesting simple rules for participation may incent larger improvement. PMID:29594189
Nelson, Sarah C.; Stilp, Adrienne M.; Papanicolaou, George J.; Taylor, Kent D.; Rotter, Jerome I.; Thornton, Timothy A.; Laurie, Cathy C.
2016-01-01
Imputation is commonly used in genome-wide association studies to expand the set of genetic variants available for analysis. Larger and more diverse reference panels, such as the final Phase 3 of the 1000 Genomes Project, hold promise for improving imputation accuracy in genetically diverse populations such as Hispanics/Latinos in the USA. Here, we sought to empirically evaluate imputation accuracy when imputing to a 1000 Genomes Phase 3 versus a Phase 1 reference, using participants from the Hispanic Community Health Study/Study of Latinos. Our assessments included calculating the correlation between imputed and observed allelic dosage in a subset of samples genotyped on a supplemental array. We observed that the Phase 3 reference yielded higher accuracy at rare variants, but that the two reference panels were comparable at common variants. At a sample level, the Phase 3 reference improved imputation accuracy in Hispanic/Latino samples from the Caribbean more than for Mainland samples, which we attribute primarily to the additional reference panel samples available in Phase 3. We conclude that a 1000 Genomes Project Phase 3 reference panel can yield improved imputation accuracy compared with Phase 1, particularly for rare variants and for samples of certain genetic ancestry compositions. Our findings can inform imputation design for other genome-wide association studies of participants with diverse ancestries, especially as larger and more diverse reference panels continue to become available. PMID:27346520
Mah, Su-Jung; Kim, Ji-Eun; Ahn, Eun Jin; Nam, Jong-Hyun; Kim, Ji-Young
2016-01-01
Skeletal anchorage-assisted upper molar distalization has become one of the standard treatment modalities for the correction of Class II malocclusion. The purpose of this study was to analyze maxillary molar movement patterns according to appliance design, with the simultaneous use of buccal fixed orthodontic appliances. The authors devised two distinct types of midpalatal miniscrew-assisted maxillary molar distalizers, a lingual arch type and a pendulum type. Fourteen patients treated with one of the two types of distalizers were enrolled in the study, and the patterns of tooth movement associated with each type were compared. Pre- and post-treatment lateral cephalograms were analyzed. The lingual arch type was associated with relatively bodily upper molar distalization, while the pendulum type was associated with distal tipping with intrusion of the upper molar. Clinicians should be aware of the expected tooth movement associated with each appliance design. Further well designed studies with larger sample sizes are required. PMID:26877983
ERIC Educational Resources Information Center
Tiede, Lynn M.
While leaders in India have been slower than other non-Western nations to encourage the sales of Western fast food products, signs of these foods are present in larger cities like Delhi, Bombay, Calcutta, and Madras. This unit of study is a series of lessons designed to introduce junior high school or high school students to various aspects of the…
Designing Assessments of Microworld Training for Combat Service Support Staff
2003-01-01
training for distribution management skills as a part of a larger project that entailed making changes to the current structure, content, and methods...of CSS training. Microworld models are small-scale simulations of organizations and operations. They are useful for training distribution management processes...pilot studies using a microworld model for U.S. Army Reserve (USAR) soldiers in Distribution Management Centers. The degree to which trainees learned
Andrew B. Self; Andrew W. Ezell; Michael R. Guttery
2006-01-01
Oak seedlings are annually planted on thousands of acres in the South. While the majority of these seedlings are planted for timber production, there is increasing interest in oak establishment for mast production. In this study, seedlings of nine oak species were grown under a protocol developed by Dr. Paul Kormanik designed to produce an âenhancedâ seedling of larger...
Natural Flood Management Plus: Scaling Up Nature Based Solutions to Larger Catchments
NASA Astrophysics Data System (ADS)
Quinn, Paul; Nicholson, Alex; Adams, Russ
2017-04-01
It has been established that networks NFM features, such as ponds and wetlands, can have a significant effect on flood flow and pollution at local scales (less than 10km2). However, it is much less certain that NFM and NBS can impact at larger scales and protect larger cities. This is especially true for recent storms in the UK such as storm Desmond that caused devastation across the north of England. It is possible using observed rainfall and runoff data to estimate the amounts of storage that would be required to impact on extreme flood events. Here we will how a toolkit that will estimate the amount of storage that can be accrued through a dense networks of NFM features. The analysis suggest that the use of many hundreds of small NFM features can have a significant impact on peak flow, however we still require more storage in order to address extreme events and to satisfy flood engineers who may propose more traditional flood defences. We will also show case studies of larger NFM feature positioned on flood plains that can store significantly more flood flow. Examples designs of NFM plus feature will be shown. The storage aggregation tool will then show the degree to which storing large amounts of flood flow in NFM plus features can contribute to flood management and estimate the likely costs. Together smaller and larger NFM features if used together can produce significant flood storage and at a much lower cost than traditional schemes.
Smith, Douglas C; Ureche, Daniel J; Davis, Jordan P; Walters, Scott T
2015-01-01
Many adolescents in need of substance use disorder treatments never engage in treatment. Further, the most promising interventions that could be adapted to target treatment engagement often use normative feedback (NF) despite concerns about its appropriateness for adolescents. This preliminary study will inform a larger trial designed to isolate whether NF is an inert, helpful, or harmful active ingredient within pretreatment motivational interviewing (MI) interventions designed to increase treatment engagement. Adolescents (N = 48) presenting for treatment intake assessments were randomized to receive MI (n = 22) or MI+NF (n = 26) immediately following their assessments. Three-month outcomes included the percentage of youth engaged in treatment, the percentage of youth reporting past-month binge drinking, and the percentage of days of abstinence. Treatments were delivered with high fidelity, and a high proportion of eligible participants were recruited and retained in this study. Participants significantly increased their percentage of days of abstinence by approximately 10% at follow-up (d = .32, P =.03), with no significant differences between groups. Fifty-five percent of youth in MI and 41.7% of youth in MI+NF engaged in treatment (odds ratio [OR] = .60, nonsignificant; 95% confidence interval, CI [0.136-2.68]). Larger trials should test whether NF is an active ingredient in adolescent MI interventions, and should also determine the mechanisms through which MI+NF may produce effects.
Smith, Douglas C.; Ureche, Daniel J.; Davis, Jordan P.; Walters, Scott T.
2015-01-01
Background Many adolescents in need of substance use disorder treatments never engage in treatment. Further, the most promising interventions that could be adapted to target treatment engagement often use normative feedback (NF) despite concerns about its appropriateness for adolescents. This preliminary study will inform a larger trial designed to isolate whether NF is an inert, helpful, or harmful active ingredient within pre-treatment Motivational Interviewing (MI) interventions designed to increase treatment engagement. Methods Adolescents (n=48) presenting for treatment intake assessments were randomized to receive MI (n=22) or MI +NF (n=26) immediately following their assessments. Three-month outcomes included the percentage of youth engaged in treatment, the percentage of youth reporting past month binge drinking, and the percentage of days of abstinence. Results Treatments were delivered with high fidelity, and a high proportion of eligible participants were recruited and retained in this study. Participants significantly increased their percentage of days of abstinence by approximately 10% at follow up (d=.32, p =.03), with no significant differences between groups. Fifty-five percent of youth in MI and 41.7% of youth in MI+NF engaged in treatment (OR=.60, ns, 95% CI [.136 – 2.68]). Conclusions Larger trials should test whether NF is an active ingredient in adolescent MI interventions, and also determine the mechanisms through which MI+NF may produce effects. PMID:25551562
Crash Energy Management Crush Zone Designs : Features, Functions and Forms
DOT National Transportation Integrated Search
2007-03-13
On March 23, 2006, a full-scale test was conducted on a passenger train retrofitted with newly developed cab and coach car crush zone designs. This test was conducted as part of a larger testing program to establish the degree of enhanced performance...
Large school bus design vehicle dimensions
DOT National Transportation Integrated Search
1998-09-01
A survey of United States school bus operators and manufacturers was conducted to define the larger sizes of school buses in regular use. A mid-60 passenger type-c bus (SB-C) and a mid-80 passenger type-D bus (SB-D) were selected as design vehicles. ...
Specifications for Thesaurus Software.
ERIC Educational Resources Information Center
Milstead, Jessica L.
1991-01-01
Presents specifications for software that is designed to support manual development and maintenance of information retrieval thesauri. Evaluation of existing software and design of custom software is discussed, requirements for integration with larger systems and for the user interface are described, and relationships among terms are discussed.…
A Bayesian sequential design using alpha spending function to control type I error.
Zhu, Han; Yu, Qingzhao
2017-10-01
We propose in this article a Bayesian sequential design using alpha spending functions to control the overall type I error in phase III clinical trials. We provide algorithms to calculate critical values, power, and sample sizes for the proposed design. Sensitivity analysis is implemented to check the effects from different prior distributions, and conservative priors are recommended. We compare the power and actual sample sizes of the proposed Bayesian sequential design with different alpha spending functions through simulations. We also compare the power of the proposed method with frequentist sequential design using the same alpha spending function. Simulations show that, at the same sample size, the proposed method provides larger power than the corresponding frequentist sequential design. It also has larger power than traditional Bayesian sequential design which sets equal critical values for all interim analyses. When compared with other alpha spending functions, O'Brien-Fleming alpha spending function has the largest power and is the most conservative in terms that at the same sample size, the null hypothesis is the least likely to be rejected at early stage of clinical trials. And finally, we show that adding a step of stop for futility in the Bayesian sequential design can reduce the overall type I error and reduce the actual sample sizes.
Avionics for a Small Robotic Inspection Spacecraft
NASA Technical Reports Server (NTRS)
Abbott, Larry; Shuler, Robert L., Jr.
2005-01-01
A report describes the tentative design of the avionics of the Mini-AERCam -- a proposed 7.5-in. (approximately 19-cm)-diameter spacecraft that would contain three digital video cameras to be used in visual inspection of the exterior of a larger spacecraft (a space shuttle or the International Space Station). The Mini-AERCam would maneuver by use of its own miniature thrusters under radio control by astronauts inside the larger spacecraft. The design of the Mini-AERCam avionics is subject to a number of constraints, most of which can be summarized as severely competing requirements to maximize radiation hardness and maneuvering, image-acquisition, and data-communication capabilities while minimizing cost, size, and power consumption. The report discusses the design constraints, the engineering approach to satisfying the constraints, and the resulting iterations of the design. The report places special emphasis on the design of a flight computer that would (1) acquire position and orientation data from a Global Positioning System receiver and a microelectromechanical gyroscope, respectively; (2) perform all flight-control (including thruster-control) computations in real time; and (3) control video, tracking, power, and illumination systems.
Development of a Super-Pressure Balloon with an Improved Design
NASA Astrophysics Data System (ADS)
Izutsu, Naoki; Akita, Daisuke; Fuke, Hideyuki; Iijima, Issei; Kato, Yoichi; Kawada, Jiro; Matsushima, Kiyoho; Matsuzaka, Yukihiko; Mizuta, Eiichi; Nakada, Takashi; Nonaka, Naoki; Saito, Yoshitaka; Takada, Atsushi; Tamura, Keisuke; Yamada, Kazuhiko; Yoshida, Tetsuya
A zero-pressure balloon used for scientific observation in the stratosphere has an unmanageable limitation that its floating altitude decreases during a nighttime because of temperature drop of the lifting gas. Since a super-pressure balloon may not change its volume, the lifetime can extend very long. We had introduced so called the ‘lobed-pumpkin’ type of super-pressure balloon that can realize a full-scale long-duration balloon and it will be in practical use in the very near future. As for larger super-pressure balloons, however, we still have some potential difficulties to be resolved. We here propose a new design suitable for a larger super-pressure balloon, which is roughly ‘lobed pumpkin with lobed cylinder’ and can adapt a single design for balloons of a wide range of volumes. Indoor inflation tests were successfully carried out with balloons designed and made by the method. It has been shown that the limit of the resisting pressure differential for a new designed balloon is same as that of a normal lobed-pumpkin balloon.
Design and Manufacturing of Extremely Low Mass Flight Systems
NASA Technical Reports Server (NTRS)
Johnson, Michael R.
2002-01-01
Extremely small flight systems pose some unusual design and manufacturing challenges. The small size of the components that make up the system generally must be built with extremely tight tolerances to maintain the functionality of the assembled item. Additionally, the total mass of the system is extremely sensitive to what would be considered small perturbations in a larger flight system. The MUSES C mission, designed, built, and operated by Japan, has a small rover provided by NASA that falls into this small flight system category. This NASA-provided rover is used as a case study of an extremely small flight system design. The issues that were encountered with the rover portion of the MUSES C program are discussed and conclusions about the recommended mass margins at different stages of a small flight system project are presented.
Concurrent airline fleet allocation and aircraft design with profit modeling for multiple airlines
NASA Astrophysics Data System (ADS)
Govindaraju, Parithi
A "System of Systems" (SoS) approach is particularly beneficial in analyzing complex large scale systems comprised of numerous independent systems -- each capable of independent operations in their own right -- that when brought in conjunction offer capabilities and performance beyond the constituents of the individual systems. The variable resource allocation problem is a type of SoS problem, which includes the allocation of "yet-to-be-designed" systems in addition to existing resources and systems. The methodology presented here expands upon earlier work that demonstrated a decomposition approach that sought to simultaneously design a new aircraft and allocate this new aircraft along with existing aircraft in an effort to meet passenger demand at minimum fleet level operating cost for a single airline. The result of this describes important characteristics of the new aircraft. The ticket price model developed and implemented here enables analysis of the system using profit maximization studies instead of cost minimization. A multiobjective problem formulation has been implemented to determine characteristics of a new aircraft that maximizes the profit of multiple airlines to recognize the fact that aircraft manufacturers sell their aircraft to multiple customers and seldom design aircraft customized to a single airline's operations. The route network characteristics of two simple airlines serve as the example problem for the initial studies. The resulting problem formulation is a mixed-integer nonlinear programming problem, which is typically difficult to solve. A sequential decomposition strategy is applied as a solution methodology by segregating the allocation (integer programming) and aircraft design (non-linear programming) subspaces. After solving a simple problem considering two airlines, the decomposition approach is then applied to two larger airline route networks representing actual airline operations in the year 2005. The decomposition strategy serves as a promising technique for future detailed analyses. Results from the profit maximization studies favor a smaller aircraft in terms of passenger capacity due to its higher yield generation capability on shorter routes while results from the cost minimization studies favor a larger aircraft due to its lower direct operating cost per seat mile.
A modified varying-stage adaptive phase II/III clinical trial design.
Dong, Gaohong; Vandemeulebroecke, Marc
2016-07-01
Conventionally, adaptive phase II/III clinical trials are carried out with a strict two-stage design. Recently, a varying-stage adaptive phase II/III clinical trial design has been developed. In this design, following the first stage, an intermediate stage can be adaptively added to obtain more data, so that a more informative decision can be made. Therefore, the number of further investigational stages is determined based upon data accumulated to the interim analysis. This design considers two plausible study endpoints, with one of them initially designated as the primary endpoint. Based on interim results, another endpoint can be switched as the primary endpoint. However, in many therapeutic areas, the primary study endpoint is well established. Therefore, we modify this design to consider one study endpoint only so that it may be more readily applicable in real clinical trial designs. Our simulations show that, the same as the original design, this modified design controls the Type I error rate, and the design parameters such as the threshold probability for the two-stage setting and the alpha allocation ratio in the two-stage setting versus the three-stage setting have a great impact on the design characteristics. However, this modified design requires a larger sample size for the initial stage, and the probability of futility becomes much higher when the threshold probability for the two-stage setting gets smaller. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.
NASA Technical Reports Server (NTRS)
Decker, Ryan; Barbre, Robert E., Jr.
2011-01-01
Impact of winds to space launch vehicle include Design, Certification Day-of-launch (DOL) steering commands (1)Develop "knockdowns" of load indicators (2) Temporal uncertainty of flight winds. Currently use databases from weather balloons. Includes discrete profiles and profile pair datasets. Issues are : (1)Larger vehicles operate near design limits during ascent 150 discrete profiles per month 110-217 seasonal 2.0 and 3.5-hour pairs Balloon rise time (one hour) and drift (up to 100 n mi) Advantages of the Alternative approach using Doppler Radar Wind Profiler (DRWP) are: (1) Obtain larger sample size (2) Provide flexibility for assessing trajectory changes due to winds (3) Better representation of flight winds.
Space assembly fixtures and aids
NASA Technical Reports Server (NTRS)
Bloom, K. A.; Lillenas, A. N.
1980-01-01
Concepts and requirements for assembly fixtures and aids necessary for the assembly and maintenance of spare platforms were studied. Emphasis was placed on erectable and deployable type structures with the shuttle orbiter as the assembly base. Both single and multiple orbiter flight cases for the platform assembly were considered. Applicable space platform assembly studies were reviewed to provide a data base for establishing the assembly fixture and aids design requirements, assembly constraints, and the development of representative design concepts. Conclusions indicated that fixture requirements will vary with platform size. Larger platforms will require translation relative to the orbiter RMS working volume. The installation of platform payloads and subsystems (e.g., utility distribution) must also be considered in the specification of assembly fixtures and aids.
Effects of Particle Size on the Shear Behavior of Coarse Grained Soils Reinforced with Geogrid.
Kim, Daehyeon; Ha, Sungwoo
2014-02-07
In order to design civil structures that are supported by soils, the shear strength parameters of soils are required. Due to the large particle size of coarse-grained soils, large direct shear tests should be performed. In this study, large direct shear tests on three types of coarse grained soils (4.5 mm, 7.9 mm, and 15.9 mm) were performed to evaluate the effects of particle size on the shear behavior of coarse grained soils with/without geogrid reinforcements. Based on the direct shear test results, it was found that, in the case of no-reinforcement, the larger the maximum particle size became, the larger the friction angle was. Compared with the no-reinforcement case, the cases reinforced with either soft geogrid or stiff geogrid have smaller friction angles. The cohesion of the soil reinforced with stiff geogrid was larger than that of the soil reinforced with soft geogrid. The difference in the shear strength occurs because the case with a stiff geogrid has more soil to geogrid contact area, leading to the reduction in interlocking between soil particles.
Defense Utility of Commercial Vessels and Craft.
1980-01-01
competence represented on this Committee include: ship design (naval architecture and marine engineering); marine transportation systems analysis; port...entire maritime industry, * including operators, designers , shipbuilders, suppliers, regulators, and researchers. This report was developed by a...larger commercial vessels now included in military contingency planning or the specially designed ships of the U.S. Navy and U.S. Coast Guard. 0 The
ERIC Educational Resources Information Center
Wilson, Thomas Royce
2017-01-01
Traditionally in higher education, online courses have been designed for computer users. However, the advent of mobile learning (m-learning) and the proliferation of smartphones have created two challenges for online students and instructional designers. First, instruction designed for a larger computer screen often loses its effectiveness when…
NASA Technical Reports Server (NTRS)
Reysa, R. P.; Price, D. F.; Olcott, T.; Gaddis, J. L.
1983-01-01
The Hyperfiltration Wash Water Recovery (HWWR) subsystem, designed to offer low-power high-volume wash water purification for extended mission spacecraft, is discussed in terms of preprototype design and configuration. Heated wash water collected from the shower, hand wash, and laundry flows into a temperature-controlled (374 K) waste storage tank. Two parallel 25 micron absolute filters at the tank outlet remove large particles from the feed stream. A positive displacement feed pump delivers wash water to the hyperfiltration module at a constant flow rate of 0.20 lpm with discharge pressure variations from 4181-7239 Kpa. The hyperfiltration membrane module is a single-pass design including 36 porous stainless steel tubes, and is designed to provide an approximate water recovery rate of 90 percent. Permeate and brine water flows are monitored by flow meters, and removal of urea and ammonia is achieved by adding 15 percent NaOCl solution to the permeate fluid stream. An alternate module design using two diameters of tubing (allowing a smaller pressure drop and a larger membrane area) gave a superior predicted performance over the first module with larger tubing throughout.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Man, Jun; Zhang, Jiangjiang; Li, Weixuan
2016-10-01
The ensemble Kalman filter (EnKF) has been widely used in parameter estimation for hydrological models. The focus of most previous studies was to develop more efficient analysis (estimation) algorithms. On the other hand, it is intuitively understandable that a well-designed sampling (data-collection) strategy should provide more informative measurements and subsequently improve the parameter estimation. In this work, a Sequential Ensemble-based Optimal Design (SEOD) method, coupled with EnKF, information theory and sequential optimal design, is proposed to improve the performance of parameter estimation. Based on the first-order and second-order statistics, different information metrics including the Shannon entropy difference (SD), degrees ofmore » freedom for signal (DFS) and relative entropy (RE) are used to design the optimal sampling strategy, respectively. The effectiveness of the proposed method is illustrated by synthetic one-dimensional and two-dimensional unsaturated flow case studies. It is shown that the designed sampling strategies can provide more accurate parameter estimation and state prediction compared with conventional sampling strategies. Optimal sampling designs based on various information metrics perform similarly in our cases. The effect of ensemble size on the optimal design is also investigated. Overall, larger ensemble size improves the parameter estimation and convergence of optimal sampling strategy. Although the proposed method is applied to unsaturated flow problems in this study, it can be equally applied in any other hydrological problems.« less
Associations of welding and manganese exposure with Parkinson disease
Borenstein, Amy R.; Nelson, Lorene M.
2012-01-01
Objective: To examine associations of welding and manganese exposure with Parkinson disease (PD) using meta-analyses of data from cohort, case-control, and mortality studies. Methods: Epidemiologic studies related to welding or manganese exposure and PD were identified in a PubMed search, article references, published reviews, and abstracts. Inclusion criteria were 1) cohort, case-control, or mortality study with relative risk (RR), odds ratio (OR), or mortality OR (MOR) and 95 confidence intervals (95% CI); 2) RR, OR, and MOR matched or adjusted for age and sex; 3) valid study design and analysis. When participants of a study were a subgroup of those in a larger study, only results of the larger study were included to assure independence of datasets. Pooled RR/OR estimates and 95% CIs were obtained using random effects models; heterogeneity of study effects were evaluated using the Q statistic and I2 index in fixed effect models. Results: Thirteen studies met inclusion criteria for the welding meta-analysis and 3 studies for the manganese exposure meta-analysis. The pooled RR for the association between welding and PD for all study designs was 0.86 (95% CI 0.80–0.92), with absence of between-study heterogeneity (I2 = 0.0). Effect measures for cohort, case-control, and mortality studies were similar (0.91, 0.82, 0.87). For the association between manganese exposure and PD, the pooled OR was 0.76 (95% CI 0.41–1.42). Conclusions: Welding and manganese exposure are not associated with increased PD risk. Possible explanations for the inverse association between welding and PD include confounding by smoking, healthy worker effect, and hormesis. PMID:22965675
ERIC Educational Resources Information Center
College and Career Readiness and Success Center, 2014
2014-01-01
This discussion guide is part of a larger practice guide designed to help state education agencies (SEAs) define measurement goals, select college and career readiness measures and indicators designed to support those goals, and use the data gathered with those measures and indicators to make informed decisions about college and career readiness…
Advanced X-Ray Timing Array Mission: Conceptual Spacecraft Design Study
NASA Technical Reports Server (NTRS)
Hopkins, R. C.; Johnson, L.; Thomas, H. D.; Wilson-Hodge, C. A.; Baysinger, M.; Maples, C. D.; Fabisinski, L.L.; Hornsby, L.; Thompson, K. S.; Miernik, J. H.
2011-01-01
The Advanced X-Ray Timing Array (AXTAR) is a mission concept for submillisecond timing of bright galactic x-ray sources. The two science instruments are the Large Area Timing Array (LATA) (a collimated instrument with 2-50-keV coverage and over 3 square meters of effective area) and a Sky Monitor (SM), which acts as a trigger for pointed observations of x-ray transients. The spacecraft conceptual design team developed two spacecraft concepts that will enable the AXTAR mission: A minimal configuration to be launched on a Taurus II and a larger configuration to be launched on a Falcon 9 or similar vehicle.
NASA Technical Reports Server (NTRS)
Merrill, Raymond Gabriel; Qu, Min; Vavrina, Matthew A.; Englander, Jacob A.; Jones, Christopher A.
2014-01-01
This paper presents mission performance analysis methods and results for the Asteroid Robotic Redirect Mission (ARRM) option to capture a free standing boulder on the surface of a 100 m or larger NEA. It details the optimization and design of heliocentric low-thrust trajectories to asteroid targets for the ARRM solar electric propulsion spacecraft. Extensive searches were conducted to determine asteroid targets with large pick-up mass potential and potential observation opportunities. Interplanetary trajectory approximations were developed in method based tools for Itokawa, Bennu, 1999 JU3, and 2008 EV5 and were validated by end-to-end integrated trajectories.
Design study of advanced model support systems for the National Transonic Facility (NTF)
NASA Technical Reports Server (NTRS)
1987-01-01
It has long been recognized that the sting (or support system) is a very critical part of the model system. The designer is frequently faced with the tradeoff of minimizing sting size, thereby compromising facility and model safety, against a larger sting and the subsequent problems of sting interference effects. In the NASA Langley Research Center National Transonic Facility (NTF), this problem is accentuated by the severe environment of high pressure/low temperature, designed into the facility to provide the desired high Reynolds number. Compromises in the configuration geometry and/or limiting the test envelope are therefore contrary to the purposes and goals of the NTF and are unacceptable. The results of an investigation aimed at improvements of 25% in both strength and Young's modulus of elasticity as compared to high strength cryogenically acceptable steels currently being used are presented. Various materials or combinations of materials were studied along with different design approaches. Design concepts were developed which included conventional material stings, advanced composites, and hybrid configurations. Candidate configurations are recommended.
Designing a suite of measurements to understand the critical zone
NASA Astrophysics Data System (ADS)
Brantley, S. L.; DiBiase, R.; Russo, T.; Shi, Y.; Lin, H.; Davis, K. J.; Kaye, M.; Hill, L.; Kaye, J.; Neal, A. L.; Eissenstat, D.; Hoagland, B.; Dere, A. L.
2015-09-01
Many scientists have begun to refer to the earth surface environment from the upper canopy to the depths of bedrock as the critical zone (CZ). Identification of the CZ as a worthy object of study implicitly posits that the study of the whole earth surface will provide benefits that do not arise when studying the individual parts. To study the CZ, however, requires prioritizing among the measurements that can be made - and we do not generally agree on the priorities. Currently, the Susquehanna Shale Hills Critical Zone Observatory (SSHCZO) is expanding from a small original study area (0.08 km2, Shale Hills catchment), to a much larger watershed (164 km2, Shavers Creek watershed) and is grappling with the necessity of prioritization. This effort is an expansion from a monolithologic first-order forested catchment to a watershed that encompasses several lithologies (shale, sandstone, limestone) and land use types (forest, agriculture). The goal of the project remains the same: to understand water, energy, gas, solute and sediment (WEGSS) fluxes that are occurring today in the context of the record of those fluxes over geologic time as recorded in soil profiles, the sedimentary record, and landscape morphology. Given the small size of the original Shale Hills catchment, the original measurement design resulted in measurement of as many parameters as possible at high temporal and spatial density. In the larger Shavers Creek watershed, however, we must focus the measurements. We describe a strategy of data collection and modelling based on a geomorphological framework that builds on the hillslope as the basic unit. Interpolation and extrapolation beyond specific sites relies on geophysical surveying, remote sensing, geomorphic analysis, the study of natural integrators such as streams, ground waters or air, and application of a suite of CZ models. In essence, we are hypothesizing that pinpointed measurements of a few important variables at strategic locations will allow development of predictive models of CZ behavior. In turn, the measurements and models will reveal how the larger watershed will respond to perturbations both now and into the future.
AMLCD cockpit: promise and payoffs
NASA Astrophysics Data System (ADS)
Snow, Michael P.; Jackson, Timothy W.; Meyer, Frederick M.; Reising, John M.; Hopper, Darrel G.
1999-08-01
The active matrix liquid crystal display (AMLCD) has become the preferred flight instrument technology in avionics multifunction display applications. Current bubble canopy fighter cockpit applications involve sizes up to 7.8 X 7.8 in. active display. Dual use avionics versions of AMLCD technology are now as large as 6.7 X 6.7 in. active display area in the ARINC D sized color multifunction display (MFD). This is the standard instrument in all new Boeing transport aircraft and is being retrofitted into the C-17A. A special design of the ARINC D instrument is used in the Space Shuttle cockpit upgrade. Larger sizes of AMLCD were desired when decisions were made in the early 1990s for the F-22. Commercial AMLCD technology has now produced monitors at 1280 X 1024 resolution (1.3 megapixels) in sizes of 16 to 21 in. diagonal. Each of these larger AMLCDs has more information carrying capacity than the entire F-22A cockpit instrument panel shipset, comprising six separate smaller AMLCDs (1.2 megapixels total). The larger AMLCDs are being integrated into airborne mission crewstations for use in dim ambient lighting conditions. It is now time to identify and address the technology challenges of upgrading these larger AMLCDs for sunlight readable application and of developing concepts for their integration into advanced bubble canopy fighter cockpits. The overall goals are to significantly increase the informational carrying capacity to bring both sensor and information fusion into the cockpit and, thereby, to enable a significant increase in warfighter situational awareness and effectiveness. A research cockpit was built using specialized versions of the IBM 16.1 in and two smaller 10 in. AMLCDs to examine human factors and display design issues associated with these next-generation AMLCD cockpit displays. This cockpit was later upgraded to allow greater reconfigurability and flexibility in the display hardware used to conduct part- task mission simulations. The objective optical characterization of the AMLCDs used in this simulator and the cockpit design are described. Display formats under consideration for test in this cockpit are described together with some of the basic human factors engineering issues involved. Studies conducted in this cockpit will be part of an ongoing joint effort of the hardware-focused aerospace displays team and the pilot-focused human factors team in the Air Force Research Laboratory's Crew System Interface Division. The objective of these studies is to ascertain the payoffs of the large AMLCD promise in combat cockpits.
Total temperature probes for high-temperature hypersonic boundary-layer measurements
NASA Technical Reports Server (NTRS)
Albertson, Cindy W.; Bauserman, Willard A., Jr.
1993-01-01
The design and test results of two types of total temperature probes that were used for hypersonic boundary-layer measurements are presented. The intent of each design was to minimize the total error and to maintain minimal size for measurements in boundary layers 1.0 in. thick and less. A single platinum-20-percent-rhodium shield was used in both designs to minimize radiation heat transfer losses during exposure to the high-temperature test stream. The shield of the smaller design was flattened at the flow entrance to an interior height of 0.02 in., compared with 0.03 in. for the larger design. The resulting vent-to-inlet area ratios were 60 and 50 percent. A stainless steel structural support sleeve that was used in the larger design was excluded from the smaller design, which resulted in an outer diameter of 0.059 in., to allow closer placement of the probes to each other and to the wall. These small design changes to improve resolution did not affect probe performance. Tests were conducted at boundary-layer-edge Mach numbers of 5.0 and 6.2. The nominal free-stream total temperatures were 2600 degrees and 3200 degrees R. The probes demonstrated extremely good reliability. The best performance in terms of recovery factor occurred when the wire-based Nusselt number was at least 0.04. Recommendations for future probe designs are included.
Vu, Lien T; Chen, Chao-Chang A; Yu, Chia-Wei
2018-02-05
This study aims to develop a new optical design method of soft multifocal contact lens (CLs) to obtain uniform optical power in large center-distance zone with optimized Non-Uniform Rational B-spline (NURBS). For the anterior surface profiles of CLs, the NURBS design curves are optimized to match given optical power distributions. Then, the NURBS in the center-distance zones are fitted in the corresponding spherical/aspheric curves for both data points and their centers of curvature to achieve the uniform power. Four cases of soft CLs have been manufactured by casting in shell molds by injection molding and then measured to verify the design specifications. Results of power profiles of these CLs are concord with the given clinical requirements of uniform powers in larger center-distance zone. The developed optical design method has been verified for multifocal CLs design and can be further applied for production of soft multifocal CLs.
Assessment of end-of-life design in solid-state lighting
NASA Astrophysics Data System (ADS)
Dzombak, Rachel; Padon, Jack; Salsbury, Josh; Dillon, Heather
2017-08-01
Consumers in the US market and across the globe are beginning to widely adopt light emitting diode (LED) lighting products while the technology continues to undergo significant changes. While LED products are evolving to consume less energy, they are also more complex than traditional lighting products with a higher number of parts and a larger number of electronic components. Enthusiasm around the efficiency and long expected life span of LED lighting products is valid, but research to optimize product characteristics and design is needed. This study seeks to address that gap by characterizing LED lighting products' suitability for end of life (EOL) recycling and disposal. The authors disassembled and assessed 17 different lighting products to understand how designs differ between brands and manufacture year. Products were evaluated based on six parameters to quantify the design. The analysis indicates that while the efficiency of LED products has improved dramatically in the recent past, product designers and manufacturers could incorporate design strategies to improve environmental performance of lighting products at end-of-life.
Kaluzny, A D; Lacey, L M; Warnecke, R; Hynes, D M; Morrissey, J; Ford, L; Sondik, E
1993-01-01
OBJECTIVE. This study is designed to examine the effects of environment and structure of the Community Clinical Oncology Program (CCOP) on performance as measured by patient accrual to National Cancer Institute (NCI)-approved treatment protocols. DATA SOURCES/STUDY SETTING. Data and analysis are part of a larger evaluation of the NCI Community Clinical Oncology Program during its second funding cycle, June 1987-May 1990. Data, taken from primary and secondary sources, included a survey of selected informants in CCOPs and research bases, CCOP grant applications, CCOP annual progress reports, and site visits to a subsample of CCOPs (N = 20) and research bases (N = 5). Accrual data were obtained from NCI records. STUDY DESIGN. Analysis involved three complementary sets of factors: the local health care resources environment available to the CCOP, the larger policy environment as reflected by the relationship of the CCOP to selected research bases and the NCI, and the operational structure of the CCOP itself. A hierarchical model examined the separate and cumulative effects of local and policy environment and structure on performance. PRINCIPAL FINDINGS. Other things equal, the primary predictors of treatment accrual were: (1) the larger policy environment, as measured by the attendance of nurses at research base meetings; and (2) operational structure, as measured by the number and character of components within participating CCOPs and the number of hours per week worked by data managers. These factors explained 73 percent of the total variance in accrual performance. CONCLUSIONS. Findings suggest criteria for selecting the types of organizations to participate in the alliance, as well as for establishing guidelines for managing such alliances. A future challenge is to determine the extent to which factors predicting accrual to cancer treatment clinical trials are equally important as predictors of accrual to cancer prevention and control trials. PMID:8514498
Fathauer, L; Meek, J.
2012-01-01
Background Clinician compliance with clinical guidelines in the treatment of patients with Hepatitis C (HCV) has been reported to be as low as 18.5%. Treatment is complex and patient compliance is often inconsistent thus, active clinician surveillance and support is essential to successful outcomes. A clinical decision support system (CDSS) embedded within an electronic health record can provide reminders, summarize key data, and facilitate coordination of care. To date, the literature is bereft of information describing the implementation and evaluation of a CDSS to support HCV treatment. Objective The purpose of this case report is to describe the design, implementation, and initial evaluation of an HCV-specific CDSS while piloting data collection metrics and methods to be used in a larger study across multiple practices. Methods The case report describes the design and implementation processes with preliminary reporting on impact of the CDSS on quality indicator completion by comparing the pre-CDSS group to the post-CDSS group. Results The CDSS was successfully designed and implemented using an iterative, collaborative process. Pilot testing of the clinical outcomes of the CDSS revealed high rates of quality indicator completion in both the pre- and post-CDSS; although the post-CDSS group received a higher frequency of reminders (4.25 per patient) than the pre-CDSS group (.25 per patient). Conclusions This case report documents the processes used to successfully design and implement an HCV CDSS. While the small sample size precludes generalizability of findings, results did positively demonstrate the feasibility of comparing quality indicator completion rates pre-CDSS and post-CDSS. It is recommended that future studies include a larger sample size across multiple providers with expanded outcomes measures related to patient outcomes, staff satisfaction with the CDSS, and time studies to evaluate efficiency and cost effectiveness of the CDSS. PMID:23646082
Orgasm and women's waist circumference.
Costa, Rui Miguel; Brody, Stuart
2014-11-01
Given that adiposity is related to poorer female sexual function, among many other health problems, the present study aimed at testing the hypothesis that larger waist circumference, an index of subcutaneous and abdominal fat mass, is associated with lack of specifically vaginal orgasm. Study design One hundred and twenty Portuguese women of reproductive age had their waist measured and reported their past month frequency of penile-vaginal intercourse (PVI), vaginal orgasm, orgasm from clitoral masturbation during PVI, non-coital partnered sex (in the absence of same-day PVI), non-coital partnered sex orgasm (regardless of same-day PVI), masturbation, and masturbation orgasm. In both simple and partial correlations (controlling for age, social desirability responding, relationship status, and cohabitation status), larger waist circumference was associated with lack of any vaginal orgasm and with having masturbated in the past month. In a multiple regression, larger waist circumference was independently predicted by lesser frequency of vaginal orgasm, greater frequency of masturbation, and older age. Abdominal fat mass appears to be adversely associated with lesser capacity for vaginal orgasm, but not for orgasms from other sexual activities. Results are discussed in the context of vaginal orgasm being relatively more contingent on situations of increased fitness in both partners. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
Automated CAD design for sculptured airfoil surfaces
NASA Astrophysics Data System (ADS)
Murphy, S. D.; Yeagley, S. R.
1990-11-01
The design of tightly tolerated sculptured surfaces such as those for airfoils requires a significant design effort in order to machine the tools to create these surfaces. Because of the quantity of numerical data required to describe the airfoil surfaces, a CAD approach is required. Although this approach will result in productivity gains, much larger gains can be achieved by automating the design process. This paper discusses an application which resulted in an eightfold improvement in productivity by automating the design process on the CAD system.
Preliminary design and development of a reflectance spectrometer instrument
NASA Technical Reports Server (NTRS)
Mccord, T. B.
1979-01-01
An improved design for the reflectance spectrometer is described to be used on various terrestrial body missions. These improvements were made on the original Lunar Polar Orbiter design. These include a larger entrance mirror, rectangular aperture, multiple optical beams, spatial resolution, and a bandwidth extension to 5 microns. In addition, detailed electronic designs were produced for a charge amplifier and an amplifier/demodulator/integrator. Design of a microprocessor driven test system was begun. Laboratory tests were performed on a tuning fork chopper.
NASA Astrophysics Data System (ADS)
Agrawal, Navik; Davis, Christopher C.
2008-08-01
Omnidirectional free space optical communication receivers can employ multiple non-imaging collectors, such as compound parabolic concentrators (CPCs), in an array-like fashion to increase the amount of possible light collection. CPCs can effectively channel light collected over a large aperture to a small area photodiode. The aperture to length ratio of such devices can increase the overall size of the transceiver unit, which may limit the practicality of such systems, especially when small size is desired. New non-imaging collector designs with smaller sizes, larger field of view (FOV), and comparable transmission curves to CPCs, offer alternative transceiver designs. This paper examines how transceiver performance is affected by the use of different non-imaging collector shapes that are designed for wide FOV with reduced efficiency compared with shapes such as the CPC that are designed for small FOV with optimal efficiency. Theoretical results provide evidence indicating that array-like transceiver designs using various non-imaging collector shapes with less efficient transmission curves, but a larger FOV will be an effective means for the design of omnidirectional optical transceiver units. The results also incorporate the effects of Fresnel loss at the collector exit aperture-photodiode interface, which is an important consideration for indoor omnidirectional FSO systems.
Yang, Bo; Yu, Jiakuo; Gong, Xi; Chen, Lianxu; Wang, Yongjian; Wang, Jian; Wang, Haijun; Zhang, Jiying
2014-01-01
The tibial plateau is asymmetric with a larger medial plateau. We observed from clinical practice that the shape of the tibial plateau does not always present a larger medial plateau. Tibial plateau also showed other shapes. The purpose of this study was to analyze the anthropometric data of the proximal tibia in a large group of Chinese patients undergoing total knee arthroplasty and to investigate the morphology of the resected proximal tibial surface and its gender differences. A total of 822 knees (164 males, 658 females) from the Chinese population were measured intraoperatively for medial anteroposterior (MAP) and lateral anteroposterior (LAP) dimensions of the resected proximal tibial surface. The difference of MAP and LAP (DML) was also calculated as MAP minus LAP. We then classified the data into three groups based on the DML (<-2, -2 to 2, and >2 mm) to analyze the morphology of the proximal tibia and its distribution between male and female. The shape of proximal tibial plateau was of three types: larger medial plateau type, symmetric type, and larger lateral plateau type. There were significant differences between males and females in relation to the shape distribution of the proximal tibial plateau (P < 0.05). Most of the proximal tibial plateau was asymmetric, with 517 of 822 (62.9%) tibia having a DML >2 mm and 120 of 822 (14.6%) tibia having a DML<-2 mm. Only 185 of 822 (22.5%) tibia had a DML between -2 and 2 mm. The results of this study can be used as a guideline to design tibial components with different DMLs to better match the different anthropometry of the resected tibial surface.
ERIC Educational Resources Information Center
Hartley, William L.
This curriculum project was designed primarily to be incorporated into a larger world history unit on the Holocaust and World War II. The project can be adapted for a lesson on 'situational ethics' for use in a philosophy class. The lesson requires students to examine a historical case and to write and discuss that particular case. The project's…
Supersonic Inlet Flow Control Using Localized Arc Filament Plasma Actuators
2011-05-10
Jon Schmisseur and by the Air Vehicle Directorate of the Air Force Research Laboratory is greatly appreciated. 4 Table of Contents Abstract...of interest to the U.S. Air Force and could pose significant problems depending on the specific application. This study has undertaken to investigate...experiments motivated the design of a new, larger, more flexible facility that utilize a Variable Angle Wedge to generate the impinging shock wave for
ERIC Educational Resources Information Center
Rhodes, Christopher; Brundrett, Mark
2008-01-01
This article reports on outcomes from a study funded by the National College for School Leadership designed to explore leadership talent identification, development, succession and retention in contextually different primary and secondary schools in England. It draws upon this larger project and offers evidence not seen before elsewhere. It deals…
Eco-Friendly Campuses as Teaching Tools
ERIC Educational Resources Information Center
Erwin, Stephen J.; Kearns, Thomas D.
2008-01-01
Sustainable design projects offer academic communities the opportunity to make the design and operations of their campuses part of the larger lessons of social and environmental responsibility that are integral parts of higher education. In no place is that demonstrated more clearly than in New England, with its long commitment to environmental…
Feasibility study for near-earth-object tracking by a piggybacked micro-satellite with penetrators
NASA Astrophysics Data System (ADS)
Weiss, P.; Leung, W.; Yung, K. L.
2010-05-01
As of August 2007, over 5000 near-earth-objects (NEO) have been discovered. Some already represent a potential danger to the Earth while others might become hazards in the future. The Planetary Society organised in 2007 the "Apophis Mission Design Competition" in response to this potential threat with the objective to identify promising concepts to track NEOs; the asteroid 99942 Apophis was taken as the study case. This paper describes the "Houyi" proposal which was evaluated by the competition jury as an innovative approach to this problem. Instead of launching a large satellite for NEO tracking, this novel concept proposes a miniaturized satellite that is piggybacked onto a larger (scientific) mission. Such mission design would drastically reduce the costs for NEO surveillance. The presented scenario uses the ESA's SOLO mission as a design baseline for the piggyback option. This paper summarizes the architecture of this CubeSat towards Apophis and extends the previous study by focusing on the feasibility of a piggybacked mission in terms of propulsion requirements.
Photocatalytic treatment of bioaerosols: impact of the reactor design.
Josset, Sébastien; Taranto, Jérôme; Keller, Nicolas; Keller, Valérie; Lett, Marie-Claire
2010-04-01
Comparing the UV-A photocatalytic treatment of bioaerosols contaminated with different airborne microorganisms such as L. pneumophila bacteria, T2 bacteriophage viruses and B. atrophaeus bacterial spores, pointed out a decontamination sensitivity following the bacteria > virus > bacterial spore ranking order, differing from that obtained for liquid-phase or surface UV-A photocatalytic disinfection. First-principles CFD investigation applied to a model annular photoreactor evidenced that larger the microorganism size, higher the hit probability with the photocatalytic surfaces. Applied to a commercial photocatalytic purifier case-study, the CFD calculations showed that the performances of the studied purifier could strongly benefit from rational reactor design engineering. The results obtained highlighted the required necessity to specifically investigate the removal of airborne microorganisms in terms of reactor design, and not to simply transpose the results obtained from studies performed toward chemical pollutants, especially for a successful commercial implementation of air decontamination photoreactors. This illustrated the importance of the aerodynamics in air decontamination, directly resulting from the microorganism morphology.
DeVocht, James W.; Goertz, Christine M.; Hondras, Maria A.; Long, Cynthia R.; Schaeffer, Wally; Thomann, Lauren; Spector, Michael; Stanford, Clark M.
2014-01-01
Background Temporomandibular pain has multiple etiologies and a range of therapeutic options. In this pilot study, the authors assessed the feasibility of conducting a larger trial to evaluate chiropractic treatment of temporomandibular disorders (TMDs). Methods The authors assigned 80 participants randomly into one of the following four groups, all of which included a comprehensive self-care program: reversible interocclusal splint therapy (RIST), Activator Method Chiropractic Technique (AMCT) (Activator Methods International, Phoenix), sham AMCT and self-care only. They made assessments at baseline and at month 2 and month 6, including use of the Research Diagnostic Criteria for Temporomandibular Disorders. Results The authors screened 721 potential participants and enrolled 80 people; 52 participants completed the six-month assessment. The adjusted mean change in current pain over six months, as assessed on the 11-point numerical rating scale, was 2.0 (95 percent confidence interval, 1.1-3.0) for RIST, 1.7 (0.9-2.5) for self-care only, 1.5 (0.7-2.4) for AMCT and 1.6 (0.7-2.5) for sham AMCT. The authors also assessed bothersomeness and functionality. Conclusions The authors found the study design and methodology to be manageable. They gained substantial knowledge to aid in conducting a larger study. AMCT, RIST and self-care should be evaluated in a future comparative effectiveness study. Practical Implications. This pilot study was a necessary step to prepare for a larger study that will provide clinicians with information that should be helpful when discussing treatment options for patients with TMD. PMID:24080932
Sample inlet tube for ion source
Prior, David [Hermiston, OR; Price, John [Richland, WA; Bruce, Jim [Oceanside, CA
2002-09-24
An improved inlet tube is positioned within an aperture through the device to allow the passage of ions from the ion source, through the improved inlet tube, and into the interior of the device. The inlet tube is designed with a larger end and a smaller end wherein the larger end has a larger interior diameter than the interior diameter of the smaller end. The inlet tube is positioned within the aperture such that the larger end is pointed towards the ion source, to receive ions therefrom, and the smaller end is directed towards the interior of the device, to deliver the ions thereto. Preferably, the ion source utilized in the operation of the present invention is a standard electrospray ionization source. Similarly, the present invention finds particular utility in conjunction with analytical devices such as mass spectrometers.
Inagaki, Taichi; Ishida, Toyokazu
2016-09-14
Thermal storage, a technology that enables us to control thermal energy, makes it possible to reuse a huge amount of waste heat, and materials with the ability to treat larger thermal energy are in high demand for energy-saving societies. Sugar alcohols are now one promising candidate for phase change materials (PCMs) because of their large thermal storage density. In this study, we computationally design experimentally unknown non-natural sugar alcohols and predict their thermal storage density as a basic step toward the development of new high performance PCMs. The non-natural sugar alcohol molecules are constructed in silico in accordance with the previously suggested molecular design guidelines: linear elongation of a carbon backbone, separated distribution of OH groups, and even numbers of carbon atoms. Their crystal structures are then predicted using the random search method and first-principles calculations. Our molecular simulation results clearly demonstrate that the non-natural sugar alcohols have potential ability to have thermal storage density up to ∼450-500 kJ/kg, which is significantly larger than the maximum thermal storage density of the present known organic PCMs (∼350 kJ/kg). This computational study suggests that, even in the case of H-bonded molecular crystals where the electrostatic energy contributes mainly to thermal storage density, the molecular distortion and van der Waals energies are also important factors to increase thermal storage density. In addition, the comparison between the three eight-carbon non-natural sugar alcohol isomers indicates that the selection of preferable isomers is also essential for large thermal storage density.
Design of clinical trials of antidepressants: should a placebo control arm be included?
Fritze, J; Möller, H J
2001-01-01
There is no doubt that available antidepressants are efficacious and effective. Nevertheless, more effective drugs with improved tolerability are needed. With this need in mind, some protagonists claim that future antidepressants should be proved superior to, or at least as effective as, established antidepressants, making placebo control methodologically dispensable in clinical trials. Moreover, the use of placebo control is criticised as unethical because it might result in effective treatment being withheld. There are, however, a number of methodological reasons why placebo control is indispensable for the proof of efficacy of antidepressants. Comparing investigational antidepressants only with standard antidepressants and not placebo yields ambiguous results that are difficult to interpret, be it in superiority or equivalence testing, and this method of assessment requires larger sample sizes than those required with the use of placebo control. Experimental methodology not adhering to the optimal study design is ethically questionable. Restricting the testing of investigational antidepressants only to superiority over standard antidepressants is an obstacle to therapeutic progress in terms of tolerability and the detection of innovative mechanisms of action from which certain subgroups of future patients might benefit. The use of a methodology that requires larger samples for testing of superiority or equivalence is also ethically questionable. In view of the high placebo response rates in trials of antidepressants, placebo treatment does not mean withholding effective treatment. Accepting the necessity of the clinical evaluation of new, potentially ineffective antidepressants implicitly means accepting placebo control as ethically justified. Three- or multi-arm comparisons including placebo and an active reference represent the optimal study design.
A comparison of control strategies for wave energy converters
DOE Office of Scientific and Technical Information (OSTI.GOV)
Coe, Ryan G.; Bacelli, Giorgio; Wilson, David G.
In this study, we employ a numerical model to compare the performance of a number of wave energy converter control strategies. The controllers selected for evaluation span a wide range in their requirements for implementation. Each control strategy is evaluated using a single numerical model with a set of sea states to represent a deployment site off the coast of Newport, OR. A number of metrics, ranging from power absorption to kinematics, are employed to provide a comparison of each control strategy’s performance that accounts for both relative benefits and costs. The results show a wide range of performances frommore » the different controllers and highlight the need for a holistic design approach which considers control design as a parallel component within the larger process WEC design.« less
A comparison of control strategies for wave energy converters
Coe, Ryan G.; Bacelli, Giorgio; Wilson, David G.; ...
2017-11-15
In this study, we employ a numerical model to compare the performance of a number of wave energy converter control strategies. The controllers selected for evaluation span a wide range in their requirements for implementation. Each control strategy is evaluated using a single numerical model with a set of sea states to represent a deployment site off the coast of Newport, OR. A number of metrics, ranging from power absorption to kinematics, are employed to provide a comparison of each control strategy’s performance that accounts for both relative benefits and costs. The results show a wide range of performances frommore » the different controllers and highlight the need for a holistic design approach which considers control design as a parallel component within the larger process WEC design.« less
NASA Technical Reports Server (NTRS)
Dulikravich, George S. (Editor)
1991-01-01
Papers from the Third International Conference on Inverse Design Concepts and Optimization in Engineering Sciences (ICIDES) are presented. The papers discuss current research in the general field of inverse, semi-inverse, and direct design and optimization in engineering sciences. The rapid growth of this relatively new field is due to the availability of faster and larger computing machines.
The E(thi)co-Political Aesthetics of Designer Water: The Need for a Strategic Visual Pedagogy
ERIC Educational Resources Information Center
Jagodzinski, Jan
2007-01-01
This essay attempts to affectively politicize the visual art educator to the global condition of water in the larger context of designer capitalism. The ethical concerns of "designer water" are raised within the broader agenda of ecosophy as inspired by Giles Deleuze and by the last great essay by Felix Guattari. The essay takes an aesthetic line…
Enhanced spin-torque in double tunnel junctions using a nonmagnetic-metal spacer
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chen, C. H.; Cheng, Y. H.; Ko, C. W.
2015-10-12
This study proposes an enhancement in the spin-transfer torque of a magnetic tunnel junction (MTJ) designed with double-barrier layer structure using a nonmagnetic metal spacer, as a replacement for the ferromagnetic material, which is traditionally used in these double-barrier stacks. Our calculation results show that the spin-transfer torque and charge current density of the proposed double-barrier MTJ can be as much as two orders of magnitude larger than the traditional double-barrier one. In other words, the proposed double-barrier MTJ has a spin-transfer torque that is three orders larger than that of the single-barrier stack. This improvement may be attributed tomore » the quantum-well states that are formed in the nonmagnetic metal spacer and the resonant tunneling mechanism that exists throughout the system.« less
NASA Astrophysics Data System (ADS)
de Goeij, B. T. G.; Otter, G. C. J.; van Wakeren, J. M. O.; Veefkind, J. P.; Vlemmix, T.; Ge, X.; Levelt, P. F.; Dirks, B. P. F.; Toet, P. M.; van der Wal, L. F.; Jansen, R.
2017-09-01
In recent years TNO has investigated and developed different innovative opto-mechanical designs to realize advanced spectrometers for space applications in a more compact and cost-effective manner. This offers multiple advantages: a compact instrument can be flown on a much smaller platform or as add-on on a larger platform; a low-cost instrument opens up the possibility to fly multiple instruments in a satellite constellation, improving both global coverage and temporal sampling (e.g. multiple overpasses per day to study diurnal processes); in this way a constellation of low-cost instruments may provide added value to the larger scientific and operational satellite missions (e.g. the Copernicus Sentinel missions); a small, lightweight spectrometer can easily be mounted on a small aircraft or high-altitude UAV (offering high spatial resolution).
Efficacy of maropitant for preventing vomiting associated with motion sickness in dogs.
Benchaoui, H A; Siedek, E M; De La Puente-Redondo, V A; Tilt, N; Rowan, T G; Clemence, R G
2007-09-29
Maropitant is a neurokinin-1 inhibitor that acts to prevent and treat vomiting by blocking stimuli to the final common pathway in the emetic centre of the brain. The field efficacy and safety of a single oral dose of maropitant were investigated for the prevention of vomiting in dogs with a history of motion sickness resulting from transportation by car in two blinded, placebo-controlled studies. In an exploratory study designed as a two-way crossover trial with 17 dogs, 10 of the dogs given the placebo vomited during a car journey but only three of the dogs vomited under maropitant treatment. In a larger multicentred parallel design study, 69 of 105 dogs treated with the placebo vomited during the journey compared with 15 of 106 dogs treated with maropitant (P < 0.0001).
NASA Technical Reports Server (NTRS)
Hardwick, Charles
1991-01-01
Field studies were conducted by MCC to determine areas of research of mutual interest to MCC and JSC. NASA personnel from the Information Systems Directorate and research faculty from UHCL/RICIS visited MCC in Austin, Texas to examine tools and applications under development in the MCC Software Technology Program. MCC personnel presented workshops in hypermedia, design knowledge capture, and design recovery on site at JSC for ISD personnel. The following programs were installed on workstations in the Software Technology Lab, NASA/JSC: (1) GERM (Graphic Entity Relations Modeler); (2) gIBIS (Graphic Issues Based Information System); and (3) DESIRE (Design Recovery tool). These applications were made available to NASA for inspection and evaluation. Programs developed in the MCC Software Technology Program run on the SUN workstation. The programs do not require special configuration, but they will require larger than usual amounts of disk space and RAM to operate properly.
Prachgosin, Tulaya; Leelasamran, Wipawan; Smithmaitrie, Pruittikorn; Chatpun, Surapong
2017-12-01
Total-contact orthosis (TCO) is one kind of foot orthosis (FO) that is used to adjust biomechanics in flexible flatfoot. To determine the effects of a TCO on the MLA moment, MLA deformation angle and lower limb biomechanics. Cross-sectional study. Seven-flatfoot and thirteen-normal foot subjects were recruited by footprint and radiographs. The biomechanics of subjects with normal foot (NF), flatfoot with shoe only (FWOT) and flatfoot with TCO (FWT) were collected in a 3D motion analysis laboratory and force plates. The MLA and lower limb biomechanics in each condition during specific sub-phases of stance were analyzed. The NF had larger MLA eversion moment after shod walking ( p = 0.001). The FWT condition compared with the FWOT condition had a significantly larger peak MLA upward moment ( p = 0.035) during pre-swing, larger peak knee external rotation angle ( p = 0.040) during mid stance, smaller peak knee extension moment during terminal stance ( p = 0.035) and a larger ground reaction force in the anterior-posterior direction during early stance ( p < 0.05). Our study found positive effects from the customized TCOs which included an increased TCO angle that led to a decreased peak MLA moment in the frontal plane in flexible flatfoot subjects during walking. Clinical relevance Lower limb biomechanics is different from normal in subjects with flexible flatfoot. The design of a TCO affects MLA, ankle and knee biomechanics and may be used to clinically correct biomechanical changes in flexible flatfoot.
Schwartz, D.P.; Joyner, W.B.; Stein, R.S.; Brown, R.D.; McGarr, A.F.; Hickman, S.H.; Bakun, W.H.
1996-01-01
Summary -- The U.S. Geological Survey was requested by the U.S. Department of the Interior to review the design values and the issue of reservoir-induced seismicity for a concrete gravity dam near the site of the previously-proposed Auburn Dam in the western foothills of the Sierra Nevada, central California. The dam is being planned as a flood-control-only dam with the possibility of conversion to a permanent water-storage facility. As a basis for planning studies the U.S. Army Corps of Engineers is using the same design values approved by the Secretary of the Interior in 1979 for the original Auburn Dam. These values were a maximum displacement of 9 inches on a fault intersecting the dam foundation, a maximum earthquake at the site of magnitude 6.5, a peak horizontal acceleration of 0.64 g, and a peak vertical acceleration of 0.39 g. In light of geological and seismological investigations conducted in the western Sierran foothills since 1979 and advances in the understanding of how earthquakes are caused and how faults behave, we have developed the following conclusions and recommendations: Maximum Displacement. Neither the pre-1979 nor the recent observations of faults in the Sierran foothills precisely define the maximum displacement per event on a fault intersecting the dam foundation. Available field data and our current understanding of surface faulting indicate a range of values for the maximum displacement. This may require the consideration of a design value larger than 9 inches. We recommend reevaluation of the design displacement using current seismic hazard methods that incorporate uncertainty into the estimate of this design value. Maximum Earthquake Magnitude. There are no data to indicate that a significant change is necessary in the use of an M 6.5 maximum earthquake to estimate design ground motions at the dam site. However, there is a basis for estimating a range of maximum magnitudes using recent field information and new statistical fault relations. We recommend reevaluating the maximum earthquake magnitude using current seismic hazard methodology. Design Ground Motions. A large number of strong-motion records have been acquired and significant advances in understanding of ground motion have been achieved since the original evaluations. The design value for peak horizontal acceleration (0.64 g) is larger than the median of one recent study and smaller than the median value of another. The value for peak vertical acceleration (0.39 g) is somewhat smaller than median values of two recent studies. We recommend a reevaluation of the design ground motions that takes into account new ground motion data with particular attention to rock sites at small source distances. Reservoir-Induced Seismicity. The potential for reservoir-induced seismicity must be considered for the Auburn Darn project. A reservoir-induced earthquake is not expected to be larger than the maximum naturally occurring earthquake. However, the probability of an earthquake may be enhanced by reservoir impoundment. A flood-control-only project may involve a lower probability of significant induced seismicity than a multipurpose water-storage dam. There is a need to better understand and quantify the likelihood of this hazard. A methodology should be developed to quantify the potential for reservoir induced seismicity using seismicity data from the Sierran foothills, new worldwide observations of induced and triggered seismicity, and current understanding of the earthquake process. Reevaluation of Design Parameters. The reevaluation of the maximum displacement, maximum magnitude earthquake, and design ground motions can be made using available field observations from the Sierran foothills, updated statistical relations for faulting and ground motions, and current computational seismic hazard methodologies that incorporate uncertainty into the analysis. The reevaluation does not require significant new geological field studies.
Galvez, Jose A; Budovitch, Amy; Harkema, Susan J; Reinkensmeyer, David J
2011-01-01
Robotic devices are being developed to automate repetitive aspects of walking retraining after neurological injuries, in part because they might improve the consistency and quality of training. However, it is unclear how inconsistent manual training actually is or whether stepping quality depends strongly on the trainers' manual skill. The objective of this study was to quantify trainer variability of manual skill during step training using body-weight support on a treadmill and assess factors of trainer skill. We attached a sensorized orthosis to one leg of each patient with spinal cord injury and measured the shank kinematics and forces exerted by different trainers during six training sessions. An expert trainer rated the trainers' skill level based on videotape recordings. Between-trainer force variability was substantial, about two times greater than within-trainer variability. Trainer skill rating correlated strongly with two gait features: better knee extension during stance and fewer episodes of toe dragging. Better knee extension correlated directly with larger knee horizontal assistance force, but better toe clearance did not correlate with larger ankle push-up force; rather, it correlated with better knee and hip extension. These results are useful to inform robotic gait-training design.
Attentional networks in developmental dyscalculia
2010-01-01
Background Very little is known about attention deficits in developmental dyscalculia, hence, this study was designed to provide the missing information. We examined attention abilities of participants suffering from developmental dyscalculia using the attention networks test - interactions. This test was designed to examine three different attention networks--executive function, orienting and alerting--and the interactions between them. Methods Fourteen university students that were diagnosed as suffering from developmental dyscalculia--intelligence and reading abilities in the normal range and no indication of attention-deficit hyperactivity disorder--and 14 matched controls were tested using the attention networks test - interactions. All participants were given preliminary tests to measure mathematical abilities, reading, attention and intelligence. Results The results revealed deficits in the alerting network--a larger alerting effect--and in the executive function networks--a larger congruity effect in developmental dyscalculia participants. The interaction between the alerting and executive function networks was also modulated by group. In addition, developmental dyscalculia participants were slower to respond in the non-cued conditions. Conclusions These results imply specific attentional deficits in pure developmental dyscalculia. Namely, those with developmental dyscalculia seem to be deficient in the executive function and alertness networks. They suffer from difficulty in recruiting attention, in addition to the deficits in numerical processing. PMID:20157427
Attentional networks in developmental dyscalculia.
Askenazi, Sarit; Henik, Avishai
2010-01-07
Very little is known about attention deficits in developmental dyscalculia, hence, this study was designed to provide the missing information. We examined attention abilities of participants suffering from developmental dyscalculia using the attention networks test - interactions. This test was designed to examine three different attention networks--executive function, orienting and alerting--and the interactions between them. Fourteen university students that were diagnosed as suffering from developmental dyscalculia--intelligence and reading abilities in the normal range and no indication of attention-deficit hyperactivity disorder--and 14 matched controls were tested using the attention networks test-interactions. All participants were given preliminary tests to measure mathematical abilities, reading, attention and intelligence. The results revealed deficits in the alerting network--a larger alerting effect--and in the executive function networks--a larger congruity effect in developmental dyscalculia participants. The interaction between the alerting and executive function networks was also modulated by group. In addition, developmental dyscalculia participants were slower to respond in the non-cued conditions. These results imply specific attentional deficits in pure developmental dyscalculia. Namely, those with developmental dyscalculia seem to be deficient in the executive function and alertness networks. They suffer from difficulty in recruiting attention, in addition to the deficits in numerical processing.
NASA Technical Reports Server (NTRS)
Iversen, J. D.
1991-01-01
The aeolian wind tunnel is a special case of a larger subset of the wind tunnel family which is designed to simulate the atmospheric surface layer winds to small scale (a member of this larger subset is usually called an atmospheric boundary layer wind tunnel or environmental wind tunnel). The atmospheric boundary layer wind tunnel is designed to simulate, as closely as possible, the mean velocity and turbulence that occur naturally in the atmospheric boundary layer (defined as the lowest portion of the atmosphere, of the order of 500 m, in which the winds are most greatly affected by surface roughness and topography). The aeolian wind tunnel is used for two purposes: to simulate the physics of the saltation process and to model at small scale the erosional and depositional processes associated with topographic surface features. For purposes of studying aeolian effects on the surface of Mars and Venus as well as on Earth, the aeolian wind tunnel continues to prove to be a useful tool for estimating wind speeds necessary to move small particles on the three planets as well as to determine the effects of topography on the evolution of aeolian features such as wind streaks and dune patterns.
Giant ferrimagnetism and polarization in a mixed metal perovskite metal-organic framework
NASA Astrophysics Data System (ADS)
Rout, Paresh C.; Srinivasan, Varadharajan
2018-01-01
Perovskite metal-organic frameworks (MOFs) have recently emerged as potential candidates for multiferroicity. However, the compounds synthesized so far possess only weak ferromagnetism and low polarization. Additionally, the very low magnetic transition temperatures (Tc) also pose a challenge to the application of the materials. We have computationally designed a mixed metal perovskite MOF—[C(NH2)3] [(Cu0.5Mn0.5) (HCOO) 3] —that is predicted to have magnetization two orders of magnitude larger than its parent ([C (NH2)3] [Cu (HCOO) 3] ), a significantly larger polarization (9.9 μ C /cm2), and an enhanced Tc of up to 56 K, unprecedented in perovskite MOFs. A detailed study of the magnetic interactions revealed a mechanism leading to the large moments as well as the increase in the Tc. Mixing a non-Jahn-Teller ion (Mn2 +) into a Jahn-Teller host (Cu2 +) leads to competing lattice distortions which are directly responsible for the enhanced polarization. The MOF is thermodynamically stable as evidenced by the computed enthalpy of formation and can likely be synthesized. Our work represents a first step towards rational design of multiferroic perovskite MOFs through the largely unexplored mixed metal approach.
Aerodynamics and Optimal Design of Biplane Wind Turbine Blades
NASA Astrophysics Data System (ADS)
Chiu, Phillip
In order to improve energy capture and reduce the cost of wind energy, in the past few decades wind turbines have grown significantly larger. As their blades get longer, the design of the inboard region (near the blade root) becomes a trade-off between competing structural and aerodynamic requirements. State-of-the-art blades require thick airfoils near the root to efficiently support large loads inboard, but those thick airfoils have inherently poor aerodynamic performance. New designs are required to circumvent this design compromise. One such design is the "biplane blade", in which the thick airfoils in the inboard region are replaced with thinner airfoils in a biplane configuration. This design was shown previously to have significantly increased structural performance over conventional blades. In addition, the biplane airfoils can provide increased lift and aerodynamic efficiency compared to thick monoplane inboard airfoils, indicating a potential for increased power extraction. This work investigates the fundamental aerodynamic aspects, aerodynamic design and performance, and optimal structural design of the biplane blade. First, the two-dimensional aerodynamics of biplanes with relatively thick airfoils are investigated, showing unique phenomena which arise as a result of airfoil thickness. Next, the aerodynamic design of the full biplane blade is considered. Two biplane blades are designed for optimal aerodynamic loading, and their aerodynamic performance quantified. Considering blades with practical chord distributions and including the drag of the mid-blade joint, it is shown that biplane blades have comparable power output to conventional monoplane designs. The results of this analysis also show that the biplane blades can be designed with significantly less chord than conventional designs, a characteristic which enables larger blade designs. The aerodynamic loads on the biplane blades are shown to be increased in gust conditions and decreased under extreme conditions. Finally, considering these aerodynamic loads, the blade mass reductions achievable by biplane blades are quantified. The internal structure of the biplane blades are designed using a multi-disciplinary optimization which seeks to minimize mass, subject to constraints which represent realistic design requirements. Using this approach, it is shown that biplane blades can be built more than 45% lighter than a similarly-optimized conventional blade; the reasons for these mass reductions are examined in detail. As blade length is increased, these mass reductions are shown to be even more significant. These large mass reductions are indicative of significant cost of electricity reductions from rotors fitted with biplane blades. Taken together, these results show that biplane blades are a concept which can enable the next generation of larger wind turbine rotors.
Designing a suite of measurements to understand the critical zone
NASA Astrophysics Data System (ADS)
Brantley, Susan L.; DiBiase, Roman A.; Russo, Tess A.; Shi, Yuning; Lin, Henry; Davis, Kenneth J.; Kaye, Margot; Hill, Lillian; Kaye, Jason; Eissenstat, David M.; Hoagland, Beth; Dere, Ashlee L.; Neal, Andrew L.; Brubaker, Kristen M.; Arthur, Dan K.
2016-03-01
Many scientists have begun to refer to the earth surface environment from the upper canopy to the depths of bedrock as the critical zone (CZ). Identification of the CZ as an integral object worthy of study implicitly posits that the study of the whole earth surface will provide benefits that do not arise when studying the individual parts. To study the CZ, however, requires prioritizing among the measurements that can be made - and we do not generally agree on the priorities. Currently, the Susquehanna Shale Hills Critical Zone Observatory (SSHCZO) is expanding from a small original focus area (0.08 km2, Shale Hills catchment), to a larger watershed (164 km2, Shavers Creek watershed) and is grappling with the prioritization. This effort is an expansion from a monolithologic first-order forested catchment to a watershed that encompasses several lithologies (shale, sandstone, limestone) and land use types (forest, agriculture). The goal of the project remains the same: to understand water, energy, gas, solute, and sediment (WEGSS) fluxes that are occurring today in the context of the record of those fluxes over geologic time as recorded in soil profiles, the sedimentary record, and landscape morphology. Given the small size of the Shale Hills catchment, the original design incorporated measurement of as many parameters as possible at high temporal and spatial density. In the larger Shavers Creek watershed, however, we must focus the measurements. We describe a strategy of data collection and modeling based on a geomorphological and land use framework that builds on the hillslope as the basic unit. Interpolation and extrapolation beyond specific sites relies on geophysical surveying, remote sensing, geomorphic analysis, the study of natural integrators such as streams, groundwaters or air, and application of a suite of CZ models. We hypothesize that measurements of a few important variables at strategic locations within a geomorphological framework will allow development of predictive models of CZ behavior. In turn, the measurements and models will reveal how the larger watershed will respond to perturbations both now and into the future.
Multi-scale Slip Inversion Based on Simultaneous Spatial and Temporal Domain Wavelet Transform
NASA Astrophysics Data System (ADS)
Liu, W.; Yao, H.; Yang, H. Y.
2017-12-01
Finite fault inversion is a widely used method to study earthquake rupture processes. Some previous studies have proposed different methods to implement finite fault inversion, including time-domain, frequency-domain, and wavelet-domain methods. Many previous studies have found that different frequency bands show different characteristics of the seismic rupture (e.g., Wang and Mori, 2011; Yao et al., 2011, 2013; Uchide et al., 2013; Yin et al., 2017). Generally, lower frequency waveforms correspond to larger-scale rupture characteristics while higher frequency data are representative of smaller-scale ones. Therefore, multi-scale analysis can help us understand the earthquake rupture process thoroughly from larger scale to smaller scale. By the use of wavelet transform, the wavelet-domain methods can analyze both the time and frequency information of signals in different scales. Traditional wavelet-domain methods (e.g., Ji et al., 2002) implement finite fault inversion with both lower and higher frequency signals together to recover larger-scale and smaller-scale characteristics of the rupture process simultaneously. Here we propose an alternative strategy with a two-step procedure, i.e., firstly constraining the larger-scale characteristics with lower frequency signals, and then resolving the smaller-scale ones with higher frequency signals. We have designed some synthetic tests to testify our strategy and compare it with the traditional one. We also have applied our strategy to study the 2015 Gorkha Nepal earthquake using tele-seismic waveforms. Both the traditional method and our two-step strategy only analyze the data in different temporal scales (i.e., different frequency bands), while the spatial distribution of model parameters also shows multi-scale characteristics. A more sophisticated strategy is to transfer the slip model into different spatial scales, and then analyze the smooth slip distribution (larger scales) with lower frequency data firstly and more detailed slip distribution (smaller scales) with higher frequency data subsequently. We are now implementing the slip inversion using both spatial and temporal domain wavelets. This multi-scale analysis can help us better understand frequency-dependent rupture characteristics of large earthquakes.
Gullick, Margaret M; Mitra, Priya; Coch, Donna
2013-05-01
Previous event-related potential studies have indicated that both a widespread N400 and an anterior N700 index differential processing of concrete and abstract words, but the nature of these components in relation to concreteness and imagery has been unclear. Here, we separated the effects of word concreteness and task demands on the N400 and N700 in a single word processing paradigm with a within-subjects, between-tasks design and carefully controlled word stimuli. The N400 was larger to concrete words than to abstract words, and larger in the visualization task condition than in the surface task condition, with no interaction. A marked anterior N700 was elicited only by concrete words in the visualization task condition, suggesting that this component indexes imagery. These findings are consistent with a revised or extended dual coding theory according to which concrete words benefit from greater activation in both verbal and imagistic systems. Copyright © 2013 Society for Psychophysiological Research.
Caldwell, Yoko Tsui; Steffen, Patrick R
2018-01-05
Heart rate variability (HRV) is a significant marker of health outcomes with decreased HRV predicting increased disease risk. HRV is decreased in major depressive disorder (MDD) but existing treatments for depression do not return heart rate variability to normal levels even with successful treatment of depression. Heart rate variability biofeedback (HRVB) increases heart rate variability but no studies to date have examined whether combining HRVB with psychotherapy improves outcome in MDD treatment. The present study used a randomized controlled design to compare the effects of HRVB combined with psychotherapy on MDD relative to a psychotherapy treatment as usual group and to a non-depressed control group. The HRVB+psychotherapy group showed a larger increase in HRV and a larger decrease in depressive symptoms relative to the other groups over a six-week period, whereas the psychotherapy group only did not improve HRV. Results support the supplementation of psychotherapy with HRVB in the treatment of MDD. Copyright © 2018 Elsevier B.V. All rights reserved.
Sun, Min-Chul; Kim, Garam; Kim, Sang Wan; Kim, Hyun Woo; Kim, Hyungjin; Lee, Jong-Ho; Shin, Hyungcheol; Park, Byung-Gook
2012-07-01
In order to extend the conventional low power Si CMOS technology beyond the 20-nm node without SOI substrates, we propose a novel co-integration scheme to build horizontal- and vertical-channel MOSFETs together and verify the idea using TCAD simulations. From the fabrication viewpoint, it is highlighted that this scheme provides additional vertical devices with good scalability by adding a few steps to the conventional CMOS process flow for fin formation. In addition, the benefits of the co-integrated vertical devices are investigated using a TCAD device simulation. From this study, it is confirmed that the vertical device shows improved off-current control and a larger drive current when the body dimension is less than 20 nm, due to the electric field coupling effect at the double-gated channel. Finally, the benefits from the circuit design viewpoint, such as the larger midpoint gain and beta and lower power consumption, are confirmed by the mixed-mode circuit simulation study.
Representation of numerical magnitude in math-anxious individuals.
Colomé, Àngels
2018-01-01
Larger distance effects in high math-anxious individuals (HMA) performing comparison tasks have previously been interpreted as indicating less precise magnitude representation in this population. A recent study by Dietrich, Huber, Moeller, and Klein limited the effects of math anxiety to symbolic comparison, in which they found larger distance effects for HMA, despite equivalent size effects. However, the question of whether distance effects in symbolic comparison reflect the properties of the magnitude representation or decisional processes is currently under debate. This study was designed to further explore the relation between math anxiety and magnitude representation through three different tasks. HMA and low math-anxious individuals (LMA) performed a non-symbolic comparison, in which no group differences were found. Furthermore, we did not replicate previous findings in an Arabic digit comparison, in which HMA individuals showed equivalent distance effects to their LMA peers. Lastly, there were no group differences in a counting Stroop task. Altogether, an explanation of math anxiety differences in terms of less precise magnitude representation is not supported.
NASA Astrophysics Data System (ADS)
Ni, Peiyuan; Ersson, Mikael; Jonsson, Lage Tord Ingemar; Jönsson, Pär Göran
2018-04-01
Different sizes and shapes of nonmetallic inclusions in a swirling flow submerged entry nozzle (SEN) placed in a new tundish design were investigated by using a Lagrangian particle tracking scheme. The results show that inclusions in the current cylindrical tundish have difficulties remaining in the top tundish region, since a strong rotational steel flow exists in this region. This high rotational flow of 0.7 m/s provides the required momentum for the formation of a strong swirling flow inside the SEN. The results show that inclusions larger than 40 µm were found to deposit to a smaller extent on the SEN wall compared to smaller inclusions. The reason is that these large inclusions have Separation number values larger than 1. Thus, the swirling flow causes these large size inclusions to move toward the SEN center. For the nonspherical inclusions, large size inclusions were found to be deposited on the SEN wall to a larger extent, compared to spherical inclusions. More specifically, the difference of the deposited inclusion number is around 27 pct. Overall, it was found that the swirling flow contains three regions, namely, the isotropic core region, the anisotropic turbulence region and the near-wall region. Therefore, anisotropic turbulent fluctuations should be taken into account when the inclusion motion was tracked in this complex flow. In addition, many inclusions were found to deposit at the SEN inlet region. The plotted velocity distribution shows that the inlet flow is very chaotic. A high turbulent kinetic energy value of around 0.08 m2/s2 exists in this region, and a recirculating flow was also found here. These flow characteristics are harmful since they increase the inclusion transport toward the wall. Therefore, a new design of the SEN inlet should be developed in the future, with the aim to modify the inlet flow so that the inclusion deposition is reduced.
Protocol Design Challenges in the Detection of Awareness in Aware Subjects Using EEG Signals.
Henriques, J; Gabriel, D; Grigoryeva, L; Haffen, E; Moulin, T; Aubry, R; Pazart, L; Ortega, J-P
2016-10-01
Recent studies have evidenced serious difficulties in detecting covert awareness with electroencephalography-based techniques both in unresponsive patients and in healthy control subjects. This work reproduces the protocol design in two recent mental imagery studies with a larger group comprising 20 healthy volunteers. The main goal is assessing if modifications in the signal extraction techniques, training-testing/cross-validation routines, and hypotheses evoked in the statistical analysis, can provide solutions to the serious difficulties documented in the literature. The lack of robustness in the results advises for further search of alternative protocols more suitable for machine learning classification and of better performing signal treatment techniques. Specific recommendations are made using the findings in this work. © EEG and Clinical Neuroscience Society (ECNS) 2014.
Structural design using equilibrium programming formulations
NASA Technical Reports Server (NTRS)
Scotti, Stephen J.
1995-01-01
Solutions to increasingly larger structural optimization problems are desired. However, computational resources are strained to meet this need. New methods will be required to solve increasingly larger problems. The present approaches to solving large-scale problems involve approximations for the constraints of structural optimization problems and/or decomposition of the problem into multiple subproblems that can be solved in parallel. An area of game theory, equilibrium programming (also known as noncooperative game theory), can be used to unify these existing approaches from a theoretical point of view (considering the existence and optimality of solutions), and be used as a framework for the development of new methods for solving large-scale optimization problems. Equilibrium programming theory is described, and existing design techniques such as fully stressed design and constraint approximations are shown to fit within its framework. Two new structural design formulations are also derived. The first new formulation is another approximation technique which is a general updating scheme for the sensitivity derivatives of design constraints. The second new formulation uses a substructure-based decomposition of the structure for analysis and sensitivity calculations. Significant computational benefits of the new formulations compared with a conventional method are demonstrated.
Space Station Human Factors: Designing a Human-Robot Interface
NASA Technical Reports Server (NTRS)
Rochlis, Jennifer L.; Clarke, John Paul; Goza, S. Michael
2001-01-01
The experiments described in this paper are part of a larger joint MIT/NASA research effort and focus on the development of a methodology for designing and evaluating integrated interfaces for highly dexterous and multifunctional telerobot. Specifically, a telerobotic workstation is being designed for an Extravehicular Activity (EVA) anthropomorphic space station telerobot called Robonaut. Previous researchers have designed telerobotic workstations based upon performance of discrete subsets of tasks (for example, peg-in-hole, tracking, etc.) without regard for transitions that operators go through between tasks performed sequentially in the context of larger integrated tasks. The experiments presented here took an integrated approach to describing teleoperator performance and assessed how subjects operating a full-immersion telerobot perform during fine position and gross position tasks. In addition, a Robonaut simulation was also developed as part of this research effort, and experimentally tested against Robonaut itself to determine its utility. Results show that subject performance of teleoperated tasks using both Robonaut and the simulation are virtually identical, with no significant difference between the two. These results indicate that the simulation can be utilized as both a Robonaut training tool, and as a powerful design platform for telepresence displays and aids.
Quantifying design trade-offs of beryllium targets on NIF
NASA Astrophysics Data System (ADS)
Yi, S. A.; Zylstra, A. B.; Kline, J. L.; Loomis, E. N.; Kyrala, G. A.; Shah, R. C.; Perry, T. S.; Kanzleiter, R. J.; Batha, S. H.; MacLaren, S. A.; Ralph, J. E.; Masse, L. P.; Salmonson, J. D.; Tipton, R. E.; Callahan, D. A.; Hurricane, O. A.
2017-10-01
An important determinant of target performance is implosion kinetic energy, which scales with the capsule size. The maximum achievable performance for a given laser is thus related to the largest capsule that can be imploded symmetrically, constrained by drive uniformity. A limiting factor for symmetric radiation drive is the ratio of hohlraum to capsule radii, or case-to-capsule ratio (CCR). For a fixed laser energy, a larger hohlraum allows for driving bigger capsules symmetrically at the cost of reduced peak radiation temperature (Tr). Beryllium ablators may thus allow for unique target design trade-offs due to their higher ablation efficiency at lower Tr. By utilizing larger hohlraum sizes than most modern NIF designs, beryllium capsules thus have the potential to operate in unique regions of the target design parameter space. We present design simulations of beryllium targets with a large CCR = 4.3 3.7 . These are scaled surrogates of large hohlraum low Tr beryllium targets, with the goal of quantifying symmetry tunability as a function of CCR. This work performed under the auspices of the U.S. DOE by LANL under contract DE-AC52- 06NA25396, and by LLNL under Contract DE-AC52-07NA27344.
Effects of video-game play on information processing: a meta-analytic investigation.
Powers, Kasey L; Brooks, Patricia J; Aldrich, Naomi J; Palladino, Melissa A; Alfieri, Louis
2013-12-01
Do video games enhance cognitive functioning? We conducted two meta-analyses based on different research designs to investigate how video games impact information-processing skills (auditory processing, executive functions, motor skills, spatial imagery, and visual processing). Quasi-experimental studies (72 studies, 318 comparisons) compare habitual gamers with controls; true experiments (46 studies, 251 comparisons) use commercial video games in training. Using random-effects models, video games led to improved information processing in both the quasi-experimental studies, d = 0.61, 95% CI [0.50, 0.73], and the true experiments, d = 0.48, 95% CI [0.35, 0.60]. Whereas the quasi-experimental studies yielded small to large effect sizes across domains, the true experiments yielded negligible effects for executive functions, which contrasted with the small to medium effect sizes in other domains. The quasi-experimental studies appeared more susceptible to bias than were the true experiments, with larger effects being reported in higher-tier than in lower-tier journals, and larger effects reported by the most active research groups in comparison with other labs. The results are further discussed with respect to other moderators and limitations in the extant literature.
Behavior analytic approaches to problem behavior in intellectual disabilities.
Hagopian, Louis P; Gregory, Meagan K
2016-03-01
The purpose of the current review is to summarize recent behavior analytic research on problem behavior in individuals with intellectual disabilities. We have focused our review on studies published from 2013 to 2015, but also included earlier studies that were relevant. Behavior analytic research on problem behavior continues to focus on the use and refinement of functional behavioral assessment procedures and function-based interventions. During the review period, a number of studies reported on procedures aimed at making functional analysis procedures more time efficient. Behavioral interventions continue to evolve, and there were several larger scale clinical studies reporting on multiple individuals. There was increased attention on the part of behavioral researchers to develop statistical methods for analysis of within subject data and continued efforts to aggregate findings across studies through evaluative reviews and meta-analyses. Findings support continued utility of functional analysis for guiding individualized interventions and for classifying problem behavior. Modifications designed to make functional analysis more efficient relative to the standard method of functional analysis were reported; however, these require further validation. Larger scale studies on behavioral assessment and treatment procedures provided additional empirical support for effectiveness of these approaches and their sustainability outside controlled clinical settings.
High pressure and high temperature apparatus
Voronov, Oleg A.
2005-09-13
A design for high pressure/high temperature apparatus and reaction cell to achieve .about.30 GPa pressure in .about.1 cm volume and .about.100 GPa pressure in .about.1 mm volumes and 20-5000.degree. C. temperatures in a static regime. The device includes profiled anvils (28) action on a reaction cell (14, 16) containing the material (26) to be processed. The reaction cell includes a heater (18) surrounded by insulating layers and screens. Surrounding the anvils are cylindrical inserts and supporting rings (30-48) whose hardness increases towards the reaction cell. These volumes may be increased considerably if applications require it, making use of presses that have larger loading force capability, larger frames and using larger anvils.
Unique Procurement Process Expands Microgrid Research Capabilities at the
competitive procurement process provided comparative research on multiple controller technologies, which will be made publicly available on GitHub. "We always set out to design and build innovative advance the design and performance of controls for future microgrids, and of the larger U.S. power system
Small-Scale Design Experiments as Working Space for Larger Mobile Communication Challenges
ERIC Educational Resources Information Center
Lowe, Sarah; Stuedahl, Dagny
2014-01-01
In this paper, a design experiment using Instagram as a cultural probe is submitted as a method for analyzing the challenges that arise when considering the implementation of social media within a distributed communication space. It outlines how small, iterative investigations can reveal deeper research questions relevant to the education of…
Integration of Mirror Design with Suspension System Using NASA's New Mirror Modeling Software
NASA Technical Reports Server (NTRS)
Arnold, William R., Sr.; Bevan, Ryan M.; Stahl, H. Philip
2013-01-01
Advances in mirror fabrication are making very large space based telescopes possible. In many applications, only monolithic mirrors can meet the performance requirements. The existing and near-term planned heavy launch vehicles place a premium on lowest possible mass, and then available payload shroud sizes limit near term designs to 4 meter class mirrors. Practical 8 meter class and beyond designs could encourage planners to include larger shrouds, if it can be proven that such mirrors can be manufactured. These two factors, lower mass and larger mirrors, present the classic optimization problem. There is a practical upper limit to how large of a mirror can be supported by a purely kinematic mount system handling both operational and launch loads. This paper shows how the suspension system and mirror blank need to be designed simultaneously. We will also explore the concepts of auxiliary support systems which act only during launch and disengage on orbit. We will define required characteristics of these systems and show how they can substantially reduce the mirror mass.
Integration of Mirror Design with Suspension System using NASA's New Mirror Modeling Software
NASA Technical Reports Server (NTRS)
Arnold,William R., Sr.; Bevan, Ryan M.; Stahl, Philip
2013-01-01
Advances in mirror fabrication are making very large space based telescopes possible. In many applications, only monolithic mirrors can meet the performance requirements. The existing and near-term planned heavy launch vehicles place a premium on lowest possible mass, and then available payload shroud sizes limit near term designs to 4 meter class mirrors. Practical 8 meter class and beyond designs could encourage planners to include larger shrouds, if it can be proven that such mirrors can be manufactured. These two factors, lower mass and larger mirrors, present the classic optimization problem. There is a practical upper limit to how large of a mirror can be supported by a purely kinematic mount system handling both operational and launch loads. This paper shows how the suspension system and mirror blank need to be designed simultaneously. We will also explore the concepts of auxiliary support systems which act only during launch and disengage on orbit. We will define required characteristics of these systems and show how they can substantially reduce the mirror mass.
Replication and contradiction of highly cited research papers in psychiatry: 10-year follow-up.
Tajika, Aran; Ogawa, Yusuke; Takeshima, Nozomi; Hayasaka, Yu; Furukawa, Toshi A
2015-10-01
Contradictions and initial overestimates are not unusual among highly cited studies. However, this issue has not been researched in psychiatry. Aims: To assess how highly cited studies in psychiatry are replicated by subsequent studies. We selected highly cited studies claiming effective psychiatric treatments in the years 2000 through 2002. For each of these studies we searched for subsequent studies with a better-controlled design, or with a similar design but a larger sample. Among 83 articles recommending effective interventions, 40 had not been subject to any attempt at replication, 16 were contradicted, 11 were found to have substantially smaller effects and only 16 were replicated. The standardised mean differences of the initial studies were overestimated by 132%. Studies with a total sample size of 100 or more tended to produce replicable results. Caution is needed when a study with a small sample size reports a large effect. © The Royal College of Psychiatrists 2015.
Further Studies of Aerodynamic Loads at Spin Entry
1977-06-30
the model and the loads on the model for a research coafiguration having certain essential features of a modern fighter-bomber aircraft, since no such...percent at the tip. The model is geometrically similar to that described in reference 3 but approximately 2.4 times larger. The NASA model is designed to...measurements turned out to be extremely time consuming. Even though the V/STOL tunnel staff granted three additional days over the 10 originally scheduled for
Some Impacts of Risk-Centric Certification Requirements for UAS
NASA Technical Reports Server (NTRS)
Neogi, Natasha A. (Inventor); Hayhurst, Kelly J.; Maddalon, Jeffrey M.; Verstynen, Harry A.
2016-01-01
This paper discusses results from a recent study that investigates certification requirements for an unmanned rotorcraft performing agricultural application operations. The process of determining appropriate requirements using a risk-centric approach revealed a number of challenges that could impact larger UAS standardization efforts. Fundamental challenges include selecting the correct level of abstraction for requirements to permit design flexibility, transforming human-centric operational requirements to aircraft airworthiness requirements, and assessing all hazards associated with the operation.
NASA Astrophysics Data System (ADS)
Zhou, Wenbo; Liu, Xiangshen; Ji, Jian
2012-09-01
In this study, efforts were placed in giving some in vitro key clues to the question on which is more efficient for the cancer hyperthermia between intracellular and extracellular modalities. Near infrared (NIR) photothermal responsive gold nanorods (GNRs) were adopted to cause cellular thermolysis either from inside or outside of cells. GNRs were synthesized with the size of 30.4 nm (in length) × 8.4 nm (in width). Demonstrated by ICP-MS (inductively coupled plasmon mass spectroscopy), UV-Vis spectroscopy and transmission electron microscopy analyses, various cell uptake doses of nanoparticles were differentiated due to different molecular designs on GNRs surfaces and different types of cells chosen (three cancer cell lines and three normal ones). Under our continuous wavelengths (CW) NIR irradiation, it resulted that the cells which internalized GNRs died faster than the cells surrounded by GNRs. Furthermore, fluorescent images and flow cytometry data also showed that the NIR photothermal therapeutic effect was greater when the amount of internalized GNRs per cell was larger. Generally speaking, the GNRs assisted intracellular hyperthermia exhibited more precise and efficient control on the selective cancer ablation. To a larger degree, such a relationship between GNRs distribution and hyperthermia efficiency might be applied to wider spectra of cell types and heat-producing nanoparticles, which provided a promise for future cancer thermal therapeutic designs.
Assessing cost-effectiveness of specific LID practice designs in response to large storm events
NASA Astrophysics Data System (ADS)
Chui, Ting Fong May; Liu, Xin; Zhan, Wenting
2016-02-01
Low impact development (LID) practices have become more important in urban stormwater management worldwide. However, most research on design optimization focuses on relatively large scale, and there is very limited information or guideline regarding individual LID practice designs (i.e., optimal depth, width and length). The objective of this study is to identify the optimal design by assessing the hydrological performance and the cost-effectiveness of different designs of LID practices at a household or business scale, and to analyze the sensitivity of the hydrological performance and the cost of the optimal design to different model and design parameters. First, EPA SWMM, automatically controlled by MATLAB, is used to obtain the peak runoff of different designs of three specific LID practices (i.e., green roof, bioretention and porous pavement) under different design storms (i.e., 2 yr and 50 yr design storms of Hong Kong, China and Seattle, U.S.). Then, life cycle cost is estimated for the different designs, and the optimal design, defined as the design with the lowest cost and at least 20% peak runoff reduction, is identified. Finally, sensitivity of the optimal design to the different design parameters is examined. The optimal design of green roof tends to be larger in area but thinner, while the optimal designs of bioretention and porous pavement tend to be smaller in area. To handle larger storms, however, it is more effective to increase the green roof depth, and to increase the area of the bioretention and porous pavement. Porous pavement is the most cost-effective for peak flow reduction, followed by bioretention and then green roof. The cost-effectiveness, measured as the peak runoff reduction/thousand Dollars of LID practices in Hong Kong (e.g., 0.02 L/103 US s, 0.15 L/103 US s and 0.93 L/103 US s for green roof, bioretention and porous pavement for 2 yr storm) is lower than that in Seattle (e.g., 0.03 L/103 US s, 0.29 L/103 US s and 1.58 L/103 US s for green roof, bioretention and porous pavement for 2 yr storm). The optimal designs are influenced by the model and design parameters (i.e., initial saturation, hydraulic conductivity and berm height). However, it overall does not affect the main trends and key insights derived, and the results are therefore generic and relevant to the household/business-scale optimal design of LID practices worldwide.
NASA Technical Reports Server (NTRS)
Gong, Qian; Groff, Tyler D.; Zimmerman, Neil; Mandell, Avi; McElwain, Michael; Rizzo, Maxime; Saxena, Prabal
2017-01-01
Based on the experience from Prototype Imaging Spectrograph for Coronagraphic Exoplanet Studies (PISCES) for WFIRST, we have moved to the flight instrument design phase. The specifications for flight IFS have similarities and differences from the prototype. This paper starts with the science and system requirement, discusses a number of critical trade-offs: such as IFS type selection, lenslet array shape and layout versus detector pixel accuracy, how to accommodate the larger Field Of View (FOV) and wider wavelength band for a potential add-on StarShade occulter. Finally, the traditional geometric optical design is also investigated and traded: reflective versus refractive, telecentric versus non-telecentric relay. The relay before the lenslet array controls the chief angle distribution on the lenslet array. Our previous paper has addressed how the relay design combined with lenslet arraypinhole mask can further compress the residual star light and increase the contrast. Finally, a complete phase A IFS optical design is presented.
Pierrillas, Philippe B; Tod, Michel; Amiel, Magali; Chenel, Marylore; Henin, Emilie
2016-09-01
The purpose of this study was to explore the impact of censoring due to animal sacrifice on parameter estimates and tumor volume calculated from two diameters in larger tumors during tumor growth experiments in preclinical studies. The type of measurement error that can be expected was also investigated. Different scenarios were challenged using the stochastic simulation and estimation process. One thousand datasets were simulated under the design of a typical tumor growth study in xenografted mice, and then, eight approaches were used for parameter estimation with the simulated datasets. The distribution of estimates and simulation-based diagnostics were computed for comparison. The different approaches were robust regarding the choice of residual error and gave equivalent results. However, by not considering missing data induced by sacrificing the animal, parameter estimates were biased and led to false inferences in terms of compound potency; the threshold concentration for tumor eradication when ignoring censoring was 581 ng.ml(-1), but the true value was 240 ng.ml(-1).
Human genetic resistance to malaria.
Williams, Thomas N
2009-01-01
This brief chapter highlights the need for caution when designing and interpreting studies aimed at seeking new genes that may be associated with malaria protection, or investigating the potential mechanisms for protection in promising candidates. Judging genetic effects on the basis of the wrong clinical phenotype and missing true protective genes because their protective effects are masked by unpredictable epistatic effects are major potential pitfalls. These issues are by no means unique to malaria: in recent years, the importance of larger sample sizes and careful phenotypic definitions have become appreciated increasingly, particularly for genome-wide studies of complex diseases (Cordell and Clayton, 2005; Burton, Tobin and Hopper, 2005). Until recently, research in the field of malaria genetics has not enjoyed the sort of funding afforded to similar work investigating diseases of importance to the developed world. However, in the last few years, coupled with advances in genetic diagnostics that have led to massive automation and falling costs per gene explored, momentum has grown towards more generous funding that brings with it the opportunity for much larger, multisite cohesive studies. The stage is set for a giant leap forward in the coming years.
Statistical Analysis of CFD Solutions from the Third AIAA Drag Prediction Workshop
NASA Technical Reports Server (NTRS)
Morrison, Joseph H.; Hemsch, Michael J.
2007-01-01
The first AIAA Drag Prediction Workshop, held in June 2001, evaluated the results from an extensive N-version test of a collection of Reynolds-Averaged Navier-Stokes CFD codes. The code-to-code scatter was more than an order of magnitude larger than desired for design and experimental validation of cruise conditions for a subsonic transport configuration. The second AIAA Drag Prediction Workshop, held in June 2003, emphasized the determination of installed pylon-nacelle drag increments and grid refinement studies. The code-to-code scatter was significantly reduced compared to the first DPW, but still larger than desired. However, grid refinement studies showed no significant improvement in code-to-code scatter with increasing grid refinement. The third Drag Prediction Workshop focused on the determination of installed side-of-body fairing drag increments and grid refinement studies for clean attached flow on wing alone configurations and for separated flow on the DLR-F6 subsonic transport model. This work evaluated the effect of grid refinement on the code-to-code scatter for the clean attached flow test cases and the separated flow test cases.
Statistical Analysis of the AIAA Drag Prediction Workshop CFD Solutions
NASA Technical Reports Server (NTRS)
Morrison, Joseph H.; Hemsch, Michael J.
2007-01-01
The first AIAA Drag Prediction Workshop (DPW), held in June 2001, evaluated the results from an extensive N-version test of a collection of Reynolds-Averaged Navier-Stokes CFD codes. The code-to-code scatter was more than an order of magnitude larger than desired for design and experimental validation of cruise conditions for a subsonic transport configuration. The second AIAA Drag Prediction Workshop, held in June 2003, emphasized the determination of installed pylon-nacelle drag increments and grid refinement studies. The code-to-code scatter was significantly reduced compared to the first DPW, but still larger than desired. However, grid refinement studies showed no significant improvement in code-to-code scatter with increasing grid refinement. The third AIAA Drag Prediction Workshop, held in June 2006, focused on the determination of installed side-of-body fairing drag increments and grid refinement studies for clean attached flow on wing alone configurations and for separated flow on the DLR-F6 subsonic transport model. This report compares the transonic cruise prediction results of the second and third workshops using statistical analysis.
Real, Kevin; Fay, Lindsey; Isaacs, Kathy; Carll-White, Allison; Schadler, Aric
2018-01-01
This study utilizes systems theory to understand how changes to physical design structures impact communication processes and patient and staff design-related outcomes. Many scholars and researchers have noted the importance of communication and teamwork for patient care quality. Few studies have examined changes to nursing station design within a systems theory framework. This study employed a multimethod, before-and-after, quasi-experimental research design. Nurses completed surveys in centralized units and later in decentralized units ( N = 26 pre , N = 51 post ). Patients completed surveys ( N = 62 pre ) in centralized units and later in decentralized units ( N = 49 post ). Surveys included quantitative measures and qualitative open-ended responses. Patients preferred the decentralized units because of larger single-occupancy rooms, greater privacy/confidentiality, and overall satisfaction with design. Nurses had a more complex response. Nurses approved the patient rooms, unit environment, and noise levels in decentralized units. However, they reported reduced access to support spaces, lower levels of team/mentoring communication, and less satisfaction with design than in centralized units. Qualitative findings supported these results. Nurses were more positive about centralized units and patients were more positive toward decentralized units. The results of this study suggest a need to understand how system components operate in concert. A major contribution of this study is the inclusion of patient satisfaction with design, an important yet overlooked fact in patient satisfaction. Healthcare design researchers and practitioners may consider how changing system interdependencies can lead to unexpected changes to communication processes and system outcomes in complex systems.
Design study of large area 8 cm x 8 cm wrapthrough cells for space station
NASA Technical Reports Server (NTRS)
Garlick, George F. J.; Lillington, David R.
1987-01-01
The design of large area silicon solar cells for the projected NASA space station is discussed. It is based on the NASA specification for the cells which calls for an 8 cm by 8 cm cell of wrapthrough type with gridded back contacts. The beginning of life (BOL) power must be 1.039 watts per cell or larger and maximum end of life (EOL) after 10 years in the prescribed orbit under an equivalent 1MeV electron radiation damage fluence of 5 times 10 to the 13th power e/square cm. On orbit efficiency is to be optimized by a low thermal absorptance goal (thermal alpha) of .63.
Reflective baffle for BepiColombo mission
NASA Astrophysics Data System (ADS)
Rugi-Grond, E.; Weigel, T.; Herren, A.; Dominguez Calvo, M.; Krähenbühl, U.; Mouricaud, D.; Vayssade, H.
2017-11-01
The BepiColombo Spacecraft can't tolerate to absorb a major fraction of the off-axis sunlight through larger payload apertures. Fortunately, there are solutions to design baffles such that they reflect the incoming radiation back through the front aperture rather than absorbing it. A Design Study, sponsored by ESA and performed by Contraves Space together with SAGEM Défense Securité, has analysed the potential of various solutions and assessed the options to manufacture them. The selected configuration has been analysed in detail for the optical, mechanical and thermal performance as well as the impact on mass and power dissipation. The size of the baffle was adapted to the needs of the BepiColombo Laser Altimeter (BELA) payload.
High-performance radial AMTEC cell design for ultra-high-power solar AMTEC systems
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hendricks, T.J.; Huang, C.
1999-07-01
Alkali Metal Thermal to Electric Conversion (AMTEC) technology is rapidly maturing for potential application in ultra-high-power solar AMTEC systems required by potential future US Air Force (USAF) spacecraft missions in medium-earth and geosynchronous orbits (MEO and GEO). Solar thermal AMTEC power systems potentially have several important advantages over current solar photovoltaic power systems in ultra-high-power spacecraft applications for USAF MEO and GEO missions. This work presents key aspects of radial AMTEC cell design to achieve high cell performance in solar AMTEC systems delivering larger than 50 kW(e) to support high power USAF missions. These missions typically require AMTEC cell conversionmore » efficiency larger than 25%. A sophisticated design parameter methodology is described and demonstrated which establishes optimum design parameters in any radial cell design to satisfy high-power mission requirements. Specific relationships, which are distinct functions of cell temperatures and pressures, define critical dependencies between key cell design parameters, particularly the impact of parasitic thermal losses on Beta Alumina Solid Electrolyte (BASE) area requirements, voltage, number of BASE tubes, and system power production for both maximum power-per-BASE-area and optimum efficiency conditions. Finally, some high-level system tradeoffs are demonstrated using the design parameter methodology to establish high-power radial cell design requirements and philosophy. The discussion highlights how to incorporate this methodology with sophisticated SINDA/FLUINT AMTEC cell modeling capabilities to determine optimum radial AMTEC cell designs.« less
Species selection for the design of gold nanobioreactor by photosynthetic organisms
NASA Astrophysics Data System (ADS)
Dahoumane, Si Amar; Djediat, Chakib; Yéprémian, Claude; Couté, Alain; Fiévet, Fernand; Coradin, Thibaud; Brayner, Roberta
2012-06-01
The design of cell-based bioreactors for inorganic particles formation requires both a better understanding of the underlying processes and the identification of most suitable organisms. With this purpose, the process of Au3+ incorporation, intracellular reduction, and Au0 nanoparticle release in the culture medium was compared for four photosynthetic microorganisms, Klebsormidium flaccidum and Cosmarium impressulum green algae, Euglena gracilis euglenoid and Anabaena flos- aquae cyanobacteria. At low gold content, the two green algae show maintained photosynthetic activity and recovered particles (ca. 10 nm in size) are similar to internal colloids, indicating a full biological control over the whole process. In similar conditions, the euglenoid exhibits a rapid loss of biological activity, due to the absence of protective extracellular polysaccharide, but could grow again after an adaptation period. This results in a larger particle size dispersity but larger reduction yield. The cyanobacteria undergo rapid cell death, due to their prokaryotic nature, leading to high gold incorporation rate but poor control over released particle size. Similar observations can be made after addition of a larger gold salt concentration when all organisms rapidly die, suggesting that part of the process is not under biological control anymore but also involves extracellular chemical reactions. Overall, fruitful information on the whole biocrystallogenesis process is gained and most suitable species for further bioreactor design can be identified, i.e., green algae with external coating.
Characterizing DNA Star-Tile-Based Nanostructures Using a Coarse-Grained Model.
Schreck, John S; Romano, Flavio; Zimmer, Matthew H; Louis, Ard A; Doye, Jonathan P K
2016-04-26
We use oxDNA, a coarse-grained model of DNA at the nucleotide level, to simulate large nanoprisms that are composed of multi-arm star tiles, in which the size of bulge loops that have been incorporated into the tile design is used to control the flexibility of the tiles. The oxDNA model predicts equilibrium structures for several different nanoprism designs that are in excellent agreement with the experimental structures as measured by cryoTEM. In particular we reproduce the chiral twisting of the top and bottom faces of the nanoprisms, as the bulge sizes in these structures are varied due to the greater flexibility of larger bulges. We are also able to follow how the properties of the star tiles evolve as the prisms are assembled. Individual star tiles are very flexible, but their structures become increasingly well-defined and rigid as they are incorporated into larger assemblies. oxDNA also finds that the experimentally observed prisms are more stable than their inverted counterparts, but interestingly this preference for the arms of the tiles to bend in a given direction only emerges after they are part of larger assemblies. These results show the potential for oxDNA to provide detailed structural insight as well as to predict the properties of DNA nanostructures and hence to aid rational design in DNA nanotechnology.
Construction, Analysis, and Data-Driven Augmentation of Supersaturated Designs
2013-09-01
guidelines and considerations. 27 Table 7. Supersaturated Design Example with 8 Runs and 14 Factors Design Factors Run x1 x2 x3 x4 x5 x6 x7 x8 x9 x10 x11...much larger than the guidelines proposed by Marley 55 and Woods (2010). They recommend the factor-to-run ratio should be less than 2. Because our ratio...established approach in experimental design: Box (1992) provided general guidelines to consider, and traditional augmentation strategies like fold-over
NASA Technical Reports Server (NTRS)
Blackburn, C. L.; Dovi, A. R.; Kurtze, W. L.; Storaasli, O. O.
1981-01-01
A computer software system for the processing and integration of engineering data and programs, called IPAD (Integrated Programs for Aerospace-Vehicle Design), is described. The ability of the system to relieve the engineer of the mundane task of input data preparation is demonstrated by the application of a prototype system to the design, analysis, and/or machining of three simple structures. Future work to further enhance the system's automated data handling and ability to handle larger and more varied design problems are also presented.
Increasing efficiency of preclinical research by group sequential designs
Piper, Sophie K.; Rex, Andre; Florez-Vargas, Oscar; Karystianis, George; Schneider, Alice; Wellwood, Ian; Siegerink, Bob; Ioannidis, John P. A.; Kimmelman, Jonathan; Dirnagl, Ulrich
2017-01-01
Despite the potential benefits of sequential designs, studies evaluating treatments or experimental manipulations in preclinical experimental biomedicine almost exclusively use classical block designs. Our aim with this article is to bring the existing methodology of group sequential designs to the attention of researchers in the preclinical field and to clearly illustrate its potential utility. Group sequential designs can offer higher efficiency than traditional methods and are increasingly used in clinical trials. Using simulation of data, we demonstrate that group sequential designs have the potential to improve the efficiency of experimental studies, even when sample sizes are very small, as is currently prevalent in preclinical experimental biomedicine. When simulating data with a large effect size of d = 1 and a sample size of n = 18 per group, sequential frequentist analysis consumes in the long run only around 80% of the planned number of experimental units. In larger trials (n = 36 per group), additional stopping rules for futility lead to the saving of resources of up to 30% compared to block designs. We argue that these savings should be invested to increase sample sizes and hence power, since the currently underpowered experiments in preclinical biomedicine are a major threat to the value and predictiveness in this research domain. PMID:28282371
Neural substrates of smoking cue reactivity: A meta-analysis of fMRI studies
Engelmann, Jeffrey M.; Versace, Francesco; Robinson, Jason D.; Minnix, Jennifer A.; Lam, Cho Y.; Cui, Yong; Brown, Victoria L.; Cinciripini, Paul M.
2012-01-01
Reactivity to smoking-related cues may be an important factor that precipitates relapse in smokers who are trying to quit. The neurobiology of smoking cue reactivity has been investigated in several fMRI studies. We combined the results of these studies using activation likelihood estimation, a meta-analytic technique for fMRI data. Results of the meta-analysis indicated that smoking cues reliably evoke larger fMRI responses than neutral cues in the extended visual system, precuneus, posterior cingulate gyrus, anterior cingulate gyrus, dorsal and medial prefrontal cortex, insula, and dorsal striatum. Subtraction meta-analyses revealed that parts of the extended visual system and dorsal prefrontal cortex are more reliably responsive to smoking cues in deprived smokers than in non-deprived smokers, and that short-duration cues presented in event-related designs produce larger responses in the extended visual system than long-duration cues presented in blocked designs. The areas that were found to be responsive to smoking cues agree with theories of the neurobiology of cue reactivity, with two exceptions. First, there was a reliable cue reactivity effect in the precuneus, which is not typically considered a brain region important to addiction. Second, we found no significant effect in the nucleus accumbens, an area that plays a critical role in addiction, but this effect may have been due to technical difficulties associated with measuring fMRI data in that region. The results of this meta-analysis suggest that the extended visual system should receive more attention in future studies of smoking cue reactivity. PMID:22206965
NASA Astrophysics Data System (ADS)
Toshimitsu, Kazuhiko; Narihara, Takahiko; Kikugawa, Hironori; Akiyoshi, Arata; Kawazu, Yuuya
2017-04-01
The effects of turbulent intensity and vortex scale of simulated natural wind on performance of a horizontal axis wind turbine (HAWT) are mainly investigated in this paper. In particular, the unsteadiness and turbulence of wind in Japan are stronger than ones in Europe and North America in general. Hence, Japanese engineers should take account of the velocity unsteadiness of natural wind at installed open-air location to design a higher performance wind turbine. Using the originally designed five wind turbines on the basis of NACA and MEL blades, the dependencies of the wind frequency and vortex scale of the simulated natural wind are presented. As the results, the power coefficient of the newly designed MEL3-type rotor in the simulated natural wind is 130% larger than one in steady wind.
Biophysics and clinical utility of irrigated-tip radiofrequency catheter ablation.
Houmsse, Mahmoud; Daoud, Emile G
2012-01-01
Catheter ablation by radiofrequency (RF) energy has successfully eliminated cardiac tachyarrhythmias. RF ablation lesions are created by thermal energy. Electrode catheters with 4-mm-tips have been adequate to ablate arrhythmias located near the endocardium; however, the 4-mm-tip electrode does not readily ablate deeper tachyarrhythmia substrate. With 8- and 10-mm-tip RF electrodes, ablation lesions were larger; yet, these catheters are associated with increased risk for coagulum, char and thrombus formation, as well as myocardial steam rupture. Cooled-tip catheter technology was designed to cool the electrode tip, prevent excessive temperatures at the electrode tip-tissue interface, and thus allow continued delivery of RF current into the surrounding tissue. This ablation system creates larger and deeper ablation lesions and minimizes steam pops and thrombus formation. The purpose of this article is to review cooled-tip RF ablation biophysics and outcomes of clinical studies as well as to discuss future technological improvements.
NASA Astrophysics Data System (ADS)
Quan, Maohua; Guo, Fengyun; Li, Meicheng; Zhao, Liancheng
2010-08-01
Atomic-scale positional resolved lattice spacing measurement is used to study the In concentration of the alloy layer in InAs/InxGa1-xSb superlattices by the molecular beam epitaxy techniques. The unstrained lattice distance d along three directions, [0 0 1], [1 1 0] and [1 1 1], was measured and the average lattice constant was calculated. The experimental lattice constants of InAs layers are almost equal to the theoretical ones. We have found that the average lattice constant of In0.25Ga0.75Sb alloy layers is in good agreement with previously reported Vegard's values, being slightly larger. The results indicate that the In concentration of x = 0.18 has a larger deviation compared with the designed values.
Synchronization of electrically coupled micromechanical oscillators with a frequency ratio of 3:1
NASA Astrophysics Data System (ADS)
Pu, Dong; Wei, Xueyong; Xu, Liu; Jiang, Zhuangde; Huan, Ronghua
2018-01-01
In this Letter, synchronization of micromechanical oscillators with a frequency ratio of 3:1 is reported. Two electrically coupled piezoresistive micromechanical oscillators are built for the study, and their oscillation frequencies are tuned via the Joule heating effect to find out the synchronization region. Experimental results show that the larger coupling strength or bias driving voltage is applied and a wider synchronization region is obtained. Interestingly, however, the oscillator's frequency tunability is dramatically reduced from -809.1 Hz/V to -23.1 Hz/V when synchronization is reached. A nearly 10-fold improvement of frequency stability at 1 s is observed from one of the synchronized oscillators, showing a comparable performance of the other. The stable high order synchronization of micromechanical oscillators is helpful to design high performance resonant sensors with a better frequency resolution and a larger scale factor.
The effects of wedge roughness on Mach formation
NASA Astrophysics Data System (ADS)
Needham, C. E.; Happ, H. J.; Dawson, D. F.
A modified HULL hydrodynamic model was used to simulate shock reflection on wedges fitted with bumps representing varying degrees of roughness. The protuberances ranged from 0.02-0.2 cm in size. The study was directed at the feasibility of and techniques for defining parametric fits for surface roughness in the HULL code. Of interest was the self-similarity of the flows, so increasingly larger protuberances would simply enhance the resolution of the calculations. The code was designed for compressible, inviscid, nonconducting fluid flows. An equation of state provides closure and a finite difference algorithm is applied to solve governing equations for conservation of mass, momentum and energy. Self-similarity failed as the surface bumps grew larger and protruded further into the flowfield. It is noted that bumps spaced further apart produced greater interference for the passage of the Mach stem than did bumps placed closer together.
Electron Spin Resonance at the Level of 1 04 Spins Using Low Impedance Superconducting Resonators
NASA Astrophysics Data System (ADS)
Eichler, C.; Sigillito, A. J.; Lyon, S. A.; Petta, J. R.
2017-01-01
We report on electron spin resonance measurements of phosphorus donors localized in a 200 μ m2 area below the inductive wire of a lumped element superconducting resonator. By combining quantum limited parametric amplification with a low impedance microwave resonator design, we are able to detect around 2 ×1 04 spins with a signal-to-noise ratio of 1 in a single shot. The 150 Hz coupling strength between the resonator field and individual spins is significantly larger than the 1-10 Hz coupling rates obtained with typical coplanar waveguide resonator designs. Because of the larger coupling rate, we find that spin relaxation is dominated by radiative decay into the resonator and dependent upon the spin-resonator detuning, as predicted by Purcell.
Sampled-data chain-observer design for a class of delayed nonlinear systems
NASA Astrophysics Data System (ADS)
Kahelras, M.; Ahmed-Ali, T.; Giri, F.; Lamnabhi-Lagarrigue, F.
2018-05-01
The problem of observer design is addressed for a class of triangular nonlinear systems with not-necessarily small delay and sampled output measurements. One more difficulty is that the system state matrix is dependent on the un-delayed output signal which is not accessible to measurement, making existing observers inapplicable. A new chain observer, composed of m elementary observers in series, is designed to compensate for output sampling and arbitrary large delays. The larger the time-delay the larger the number m. Each elementary observer includes an output predictor that is conceived to compensate for the effects of output sampling and a fractional delay. The predictors are defined by first-order ordinary differential equations (ODEs) much simpler than those of existing predictors which involve both output and state predictors. Using a small gain type analysis, sufficient conditions for the observer to be exponentially convergent are established in terms of the minimal number m of elementary observers and the maximum sampling interval.
Iversen, Marjolein M; Graue, Marit; Leksell, Janeth; Smide, Bibbi; Zoffmann, Vibeke; Sigurdardottir, Arun K
2016-06-01
Similarities and differences across borders of Nordic countries constitute a suitable context for investigating and discussing factors related to the development of diabetes nursing research over the last three decades. The present study reviewed the entire body of contemporary diabetes nursing research literature originating in four Nordic countries: Norway, Sweden, Denmark and Iceland. Our aims were (i) to catalogue and characterise trends in research designs and research areas of these studies published over time and (ii) to describe how research involving nurses in Nordic countries has contributed to diabetes research overall. The larger goal of our analyses was to produce a comprehensive picture of this research in order to guide future studies in the field. We conducted a narrative literature review by systematically searching Medline, Medline in process, EMBASE, CINAHL, PsycINFO and Cochrane databases. These searches were limited to studies published between 1979 and 2009 that had an abstract available in English or a Nordic language. Two researchers independently selected studies for analysis, leading to the inclusion of 164 relevant publications for analysis. In summary, Nordic nurse researchers have contributed to the development of new knowledge in self-management of diabetes in childhood, adolescence and adulthood, and to some extent also in the treatment and care of diabetes foot ulcers. Future research may benefit from (i) larger nurse-led research programmes organised in networks in order to share knowledge and expertise across national groups and borders, (ii) more multidisciplinary collaborations in order to promote patient-centred care and (iii) further research directed towards improving the dissemination and implementation of research findings. Using complex intervention designs and a mix of research methods will enrich the research. © 2015 Nordic College of Caring Science.
Fedewa, Alicia L; Ahn, Soyeon; Reese, Robert J; Suarez, Marietta M; Macquoid, Ahjane; Davis, Matthew C; Prout, H Thompson
2016-06-01
The present study is a quantitative synthesis of the available literature to investigate the efficacy of psychotherapy for children's mental health outcomes. In particular, this study focuses on potential moderating variables-study design, treatment, client, and therapist characteristics-that may influence therapeutic outcomes for youth but have not been thoroughly accounted for in prior meta-analytic studies. An electronic search of relevant databases resulted in 190 unpublished and published studies that met criteria for inclusion in the analysis. Effect sizes differed by study design. Pre-post-test designs resulted in absolute magnitudes of treatment effects ranging from |-0.02| to |-0.76| while treatment versus control group comparison designs resulted in absolute magnitudes of treatment effects ranging from |-0.14| to |-2.39|. Changes in youth outcomes larger than 20% were found, irrespective of study design, for outcomes focused on psychosomatization (29% reduction), school attendance (25% increase), and stress (48% reduction). The magnitude of changes after psychotherapy ranged from 6% (externalizing problems) to 48% (stress). Several moderator variables significantly influenced psychotherapy treatment effect sizes, including frequency and length of treatment as well as treatment format. However, results did not support the superiority of a single type of intervention for most outcomes. Implications for therapy with school-aged youth and future research are discussed. Copyright © 2016 Society for the Study of School Psychology. Published by Elsevier Ltd. All rights reserved.
Sensitivity analysis for axis rotation diagrid structural systems according to brace angle changes
NASA Astrophysics Data System (ADS)
Yang, Jae-Kwang; Li, Long-Yang; Park, Sung-Soo
2017-10-01
General regular shaped diagrid structures can express diverse shapes because braces are installed along the exterior faces of the structures and the structures have no columns. However, since irregular shaped structures have diverse variables, studies to assess behaviors resulting from various variables are continuously required to supplement the imperfections related to such variables. In the present study, materials elastic modulus and yield strength were selected as variables for strength that would be applied to diagrid structural systems in the form of Twisters among the irregular shaped buildings classified by Vollers and that affect the structural design of these structural systems. The purpose of this study is to conduct sensitivity analysis for axial rotation diagrid structural systems according to changes in brace angles in order to identify the design variables that have relatively larger effects and the tendencies of the sensitivity of the structures according to changes in brace angles and axial rotation angles.
A Meta-Analysis of Interventions to Reduce Loneliness
Masi, Christopher M.; Chen, Hsi-Yuan; Hawkley, Louise C.; Cacioppo, John T.
2013-01-01
Social and demographic trends are placing an increasing number of adults at risk for loneliness, an established risk factor for physical and mental illness. The growing costs of loneliness have led to a number of loneliness reduction interventions. Qualitative reviews have identified four primary intervention strategies: 1) improving social skills, 2) enhancing social support, 3) increasing opportunities for social contact, and 4) addressing maladaptive social cognition. An integrative meta-analysis of loneliness reduction interventions was conducted to quantify the effects of each strategy and to examine the potential role of moderator variables. Results revealed that single group pre-post and non-randomized comparison studies yielded larger mean effect sizes relative to randomized comparison studies. Among studies that used the latter design, the most successful interventions addressed maladaptive social cognition. This is consistent with current theories regarding loneliness and its etiology. Theoretical and methodological issues associated with designing new loneliness reduction interventions are discussed. PMID:20716644
Gas Turbine Engine Inlet Wall Design
NASA Technical Reports Server (NTRS)
Florea, Razvan Virgil (Inventor); Stucky, Mark B. (Inventor); Matalanis, Claude G. (Inventor)
2016-01-01
A gas turbine engine has an inlet duct formed to have a shape with a first ellipse in one half and a second ellipse in a second half. The second half has an upstream most end which is smaller than the first ellipse. The inlet duct has a surface defining the second ellipse which curves away from the first ellipse, such that the second ellipse is larger at an intermediate location. The second ellipse is even larger at a downstream end of the inlet duct leading into a fan.
Billy Bohannan; Hermann Habermann; Joan E. Lengel
1974-01-01
Round wood pole use has changed without accompanying advancement in engineering design data. Previous pole design was based on the assumption that maximum stress occurred at the groundline but, with the larger poles that are now being used, maximum stress may occur along the pole length. For accurate engineering analysis the shape or taper of a pole must be known. Both...
The Design of a Mathematics Problem Using Real-Life Context for Young Children
ERIC Educational Resources Information Center
Cheng, Lu Pien
2013-01-01
In this paper the teachers' learning journey on designing a mathematics problem that involves a real-life context is reported. This is part of a larger project undertaken in a primary school in Singapore where the teachers were engaged in planning, observing and critiquing mathematics lessons to investigate teaching and learning. These unique…
Knowledge and Processes in Design
1992-09-03
Orqanization Name(s) and Address(es). Self-explanatory. Block 16. Price Code. Enter approoriate price Block 8. Performing Organization Report code...NTIS on/y). Number. Enter the unique alphanumerc report number(s) assigned by the organization periorming the report. Blocks 17.-19...statement codings were then organized into larger control-flow structures centered around design components called modules. The general assumption was
Converting a C-130 Hercules into a Compound Helicopter: A Conceptual Design Study
NASA Technical Reports Server (NTRS)
Kottapalli, Anjaney P.; Harris, Franklin D.
2012-01-01
Currently, the US Military and NASA are investigating the feasibility of a Vertical/Short Take Off and Landing (VSTOL) aircraft that can provide invaluable aid in the combat theater and significantly improve the civil transportation system. The nominal military mission requirement calls for a 28-ton payload heavy lift capability while the civilian requirements calls for a 90-passenger, 1000-nm range, airliner, as noted in Reference 1. To aid in these aircraft requirements, the present study examined the conversion of a Lockheed Martin C-130 Hercules into a compound aircraft, which would demonstrate the technology required by a much larger version. The present study examined various configurations and rotor blade designs in order to fulfill the nominal mission described previously. It was shown that the initial design of a 180 ft diameter rotor to lift 155,000 lb was not feasible due to material constraints. A revised design, in which the rotor radius was reduced to 55 ft, met the given constraints but required too much power. The decision was made to move to a twin rotor compound to take advantage of the increased disc area and drop the need for anti torque devices. Following this design shift, a new design point was found where all five constraints were met and the power requirements were deemed reasonable. This twin-rotor design was used in NDARC to provide a complete sizing analysis of the chosen design point.
Dzulkarnain, Ahmad Aidil Arafat; Noor Ibrahim, Siti Hajra Mu'minah; Anuar, Nur Farah Aida; Abdullah, Siti Aisyah; Tengku Zam Zam, Tengku Zulaila Hasma; Rahmat, Sarah; Mohd Ruzai, Muhammad Amar
2017-10-01
To investigate the influence of two different electrode montages (ipsilateral: reference to mastoid and vertical: reference to nape of neck) to the ABR results recorded using a level-specific (LS)-CE-Chirp® in normally hearing subjects at multiple intensities levels. Quasi-experimental and repeated measure study designs were applied in this study. Two different stopping criteria were used, (1) a fixed-signal averaging 4000 sweeps and, (2) a minimum quality indicator of Fmp = 3.1 with a minimum of 800 sweeps. Twenty-nine normally hearing adults (18 females, 11 male) participated. Wave V amplitudes were significantly larger in the LS CE-Chirp® recorded from the vertical montage than the ipsilateral montage. Waves I and III amplitudes were significantly larger from the ipsilateral LS CE-Chirp® than from the other montages and stimulus combinations. The differences in the quality of the ABR recording between the vertical and ipsilateral montages were marginal. Overall, the result suggested that the vertical LS CE-Chirp® ABR had a high potential for a threshold-seeking application, because it produced a higher wave V amplitude. The Ipsilateral LS CE-Chirp® ABR, on the other hand, might also have a high potential for the site of lesion application, because it produced larger waves I and III amplitudes.
Experimental Study on the Propulsion Performance of the M-shape flapping wing’s bending angle
NASA Astrophysics Data System (ADS)
Chen, Jingxian; Nie, Xiaofang; Zhou, Ximing
2017-10-01
To study the the effect of flapping wing with different bending angles α on the thrust, in this paper, 9 M-shape flapping wing models with different bending angles, ranging for 0° to 22°, were designed. The rotating arm experiment was adopted to conduct the thrust test on the flapping wing models with different bending angels under the wind speed of 15m/s. The result shows that the span-wise flapping wing’s curvature could rectify the airflow, the proper curvature could prevent the span-wise airflow at the surface the flapping wing and leads the airflow towards backward, the amount of air pushed backwards by the flapping wing is larger, therefore the value of thrust is increased; As well as the rectification of M-shape flapping wing increases the thrust value, the flapping wing’s form drag also increased due to the bending angle. According to the results of the experiment, when the bending angle is less than 12°, the increment of the thrust is larger than the decrease of the form drag, so the thrust value increases gradually. However, when the bending angle is larger than 12°, the increment of the thrust is less than the decrease of the form drag, so the thrust value decreases. The thrust value is the largest when the bending angle is 12°.
Woodall, Lucy C; Otero-Ferrer, Francisco; Correia, Miguel; Curtis, Janelle M R; Garrick-Maidment, Neil; Shaw, Paul W; Koldewey, Heather J
2018-01-01
Accurate taxonomy, population demography, and habitat descriptors inform species threat assessments and the design of effective conservation measures. Here we combine published studies with new genetic, morphological and habitat data that were collected from seahorse populations located along the European and North African coastlines to help inform management decisions for European seahorses. This study confirms the presence of only two native seahorse species ( Hippocampus guttulatus and H. hippocampus ) across Europe, with sporadic occurrence of non-native seahorse species in European waters. For the two native species, our findings demonstrate that highly variable morphological characteristics, such as size and presence or number of cirri, are unreliable for distinguishing species. Both species exhibit sex dimorphism with females being significantly larger. Across its range, H. guttulatus were larger and found at higher densities in cooler waters, and individuals in the Black Sea were significantly smaller than in other populations. H. hippocampus were significantly larger in Senegal. Hippocampus guttulatus tends to have higher density populations than H. hippocampus when they occur sympatrically. Although these species are often associated with seagrass beds, data show both species inhabit a wide variety of shallow habitats and use a mixture of holdfasts. We suggest an international mosaic of protected areas focused on multiple habitat types as the first step to successful assessment, monitoring and conservation management of these Data Deficient species.
Does wine glass size influence sales for on-site consumption? A multiple treatment reversal design.
Pechey, Rachel; Couturier, Dominique-Laurent; Hollands, Gareth J; Mantzari, Eleni; Munafò, Marcus R; Marteau, Theresa M
2016-06-07
Wine glass size can influence both perceptions of portion size and the amount poured, but its impact upon purchasing and consumption is unknown. This study aimed to examine the impact of wine glass size on wine sales for on-site consumption, keeping portion size constant. In one establishment (with separate bar and restaurant areas) in Cambridge, England, wine glass size (Standard; Larger; Smaller) was changed over eight fortnightly periods. The bar and restaurant differ in wine sales by the glass vs. by the bottle (93 % vs. 63 % by the glass respectively). Daily wine volume purchased was 9.4 % (95 % CI: 1.9, 17.5) higher when sold in larger compared to standard-sized glasses. This effect seemed principally driven by sales in the bar area (bar: 14.4 % [3.3, 26.7]; restaurant: 8.2 % [-2.5, 20.1]). Findings were inconclusive as to whether sales were different with smaller vs. standard-sized glasses. The size of glasses in which wine is sold, keeping the portion size constant, can affect consumption, with larger glasses increasing consumption. The hypothesised mechanisms for these differential effects need to be tested in a replication study. If replicated, policy implications could include considering glass size amongst alcohol licensing requirements. ISRCTN registry: ISRCTN12018175 . Registered 12(th) May 2015.
NASA Technical Reports Server (NTRS)
Darnell, W. L.; Wessel, V. W.
1974-01-01
The feasibility of a small Mars rover for use on a 1979 or 1981 Viking mission was studied and a preliminary design concept was developed. Three variations of the concept were developed to provide comparisons in mobility and science capability of the rover. Final masses of the three rover designs were approximately 35 kg, 40 kg, and 69 kg. The smallest rover is umbilically connected to the lander for power and communications purposes whereas the larger two rovers have secondary battery power and a 2-way very high frequency communication link to the lander. The capability for carrying Viking rovers (including development system) to the surface of Mars was considered first. It was found to be feasible to carry rovers of over 100 kg. Virtually all rover systems were then studied briefly to determine a feasible system concept and a practical interface with the comparable system of a 1979 or 1981 lander vehicle.
Analysis of an adjustable field permanent magnet solenoid
NASA Astrophysics Data System (ADS)
Burris-Mog, T.; Burns, M.; Chavez, A.; Schillig, J.
2017-10-01
A feasibility study has been performed on an adjustable-field permanent magnet (PM) solenoid concept in an effort to reduce the dependence that linear induction accelerators have on large direct current power supplies and associated cooling systems. The concept relies on the ability to reorient sections of the PMs and thus redirect their magnetization vector to either add to or subtract from the on-axis magnetic field. This study concentrated on the focal strengths and emittance growths for two different designs, both with 19 cm bore diameters extending 53 cm in length. The first design is expected to produce peak magnetic fields ranging from 260 to 900 G (0.026 to 0.09 T) while the second design is expected to produce peak magnetic fields ranging from 580 to 2100 G (0.058 to 0.21 T). Although the PM configuration generates a variable magnetic field and the torques acting on PMs within the assembly appear manageable, the emittance growth is larger than that of a DC solenoid.
Analysis of an Adjustable Field Permanent Magnet Solenoid
Burris-Mog, Trevor John; Burns, Michael James; Chavez, Mark Anthony; ...
2017-07-12
A feasibility study has been performed on an adjustable-field permanent magnet (PM) solenoid concept in an effort to reduce the dependence that linear induction accelerators have on large direct current power supplies and associated cooling systems. The concept relies on the ability to reorient sections of the PMs and thus redirect their magnetization vector to either add to or subtract from the on-axis magnetic field. This study concentrated on the focal strengths and emittance growths for two different designs, both with 19 cm bore diameters extending 53 cm in length. The first design is expected to produce peak magnetic fieldsmore » ranging from 260 to 900 G (0.026 to 0.09 T) while the second design is expected to produce peak magnetic fields ranging from 580 to 2100 G (0.058 to 0.21 T). Finally, although the PM configuration generates a variable magnetic field and the torques acting on PMs within the assembly appear manageable, the emittance growth is larger than that of a DC solenoid.« less
Guillaumier, Ashleigh; Bonevski, Billie; Paul, Chris; Durkin, Sarah; D'Este, Catherine
2014-01-01
Objectives This study aimed to test the potential impact of plain packaging for cigarettes on brand appeal among highly socioeconomically disadvantaged smokers using the new design for cigarettes implemented in Australia, which combines plain packaging with larger health warning labels. Design A 2×2 factorial design trial embedded within a cross-sectional computer touchscreen survey. Data were collected between March and December 2012. Setting Socially disadvantaged welfare aid recipients were recruited through a large Social and Community Service Organisation in New South Wales, Australia. Participants N=354 smokers. The majority of the sample had not completed high school (64%), earned less than $A300/week (55%) and received their income from Government payments (95%). Interventions Participants were randomised to one of the four different pack conditions determined by brand name: Winfield versus Benson & Hedges, and packaging type: branded versus plain. Participants were required to rate their assigned pack on measures of brand appeal and purchase intentions. Results Plain packaging was associated with significantly reduced smoker ratings of ‘positive pack characteristics’ (p<0.001), ‘positive smoker characteristics’ (p=0.003) and ‘positive taste characteristics’ (p=0.033) in the Winfield brand name condition only. Across the four pack conditions, no main differences were found for ‘negative smoker characteristics’ (p=0.427) or ‘negative harm characteristics’ (p=0.411). In comparison to plain packaging, the presentation of branded packaging was associated with higher odds of smokers’ purchase intentions (OR=2.18, 95% CI 1.34 to 3.54; p=0.002). Conclusions Plain packs stripped of branding elements, featuring larger health warning labels, were associated with reduced positive cigarette brand image and purchase intentions among highly socioeconomically disadvantaged smokers. PMID:24503299
Partial correction of irregular aniseikonia secondary to retinal traction.
Currie, Debra
2012-07-01
This case report presents the management of symptomatic retinally induced aniseikonia and a short review of the literature pertaining to two clinical tests used in the measurement and management of aniseikonia. The clinician is also provided a review of how to design eikonic lenses. A 30-year-old white male presented with symptoms of perceived image size difference after scleral buckle repair for retinal detachment in the right eye. Three measures of aniseikonia resulted in markedly different values, but all indicated larger perceived left eye image. Stereopsis was measured before and after placing an afocal magnifying lens over the right eye. Stereopsis improved immediately upon placement of the afocal lens, with further improvement after 20 minutes, and stereopsis decreased upon removal. The patient reported improved visual comfort for near work with the afocal lens. Eikonic glasses were designed, and the patient reported improved comfort for near work that has remained for over 1 year of wear. Studies evaluating the validity and reliability of the New Aniseikonia Test and the Aniseikonia Inspector are reviewed. Most studies report that induced aniseikonia is underestimated. This case report illustrates that despite the problem with underestimation, these tests are useful clinical tools to identify whether aniseikonia exists and which eye has the larger perceived image. Results can be used as a starting point when making clinical decisions about managing aniseikonia. The Aniseikonia Inspector also assists in the design of eikonic glasses. Even when aniseikonia is substantial, variable in magnitude, and irregular due to retinal disease, reducing the overall aniseikonia can improve binocularity and patient's comfort noticeably for the long term. The underestimation of induced aniseikonia in clinical tests does not preclude their use as a tool in the management of symptomatic aniseikonia.
NASA Astrophysics Data System (ADS)
Sappington, Rodney W.
2005-04-01
In research conducted at academic and community hospitals in the United States since 2001, this paper examines complex human and technological relationships employed to renegotiate behavior within hospital administrative and clinical cultures. In the planning and implementation of PACS in a four-facility hospital we will enter into what can be described as processes of "adoption" and "resistance", seemingly opposite approaches to system implementation, which I argue are in fact key responses to planning, design, and customization of imaging and information systems in a context of convergence. In a larger context of convergence known as NBIC tools (nanotechnology, biotechnology, information technology, and cognitive sciences) it has become increasingly clear to leaders in the field that it is essential to redesign organizational technologies. A novel system has little chance of being fully utilized by conventional organizational structures in an era of system convergence. The challenge of embracing a larger systems perspective lies in opening untapped potential within the healthcare enterprise by preparing the ground for reflection on new approaches to training, and bridging specialized knowledge across computer engineering, clinical decision making, and organizational perspectives for the benefit of patient care. Case studies will demonstrate how organizational and system design technologies are crucial in insuring that PACS implementation strategies can encourage the emergence of new levels of quality for patient care. The goal is to provide successful design-build models that are true to organizational specificity, persons, and clinical practices undergoing change and uncertainty.
Dwyer, Mirjana Dimitrijev; He, Lizhong; James, Michael; Nelson, Andrew; Middelberg, Anton P. J.
2013-01-01
Mixtures of a large, structured protein with a smaller, unstructured component are inherently complex and hard to characterize at interfaces, leading to difficulties in understanding their interfacial behaviours and, therefore, formulation optimization. Here, we investigated interfacial properties of such a mixed system. Simplicity was achieved using designed sequences in which chemical differences had been eliminated to isolate the effect of molecular size and structure, namely a short unstructured peptide (DAMP1) and its longer structured protein concatamer (DAMP4). Interfacial tension measurements suggested that the size and bulk structuring of the larger molecule led to much slower adsorption kinetics. Neutron reflectometry at equilibrium revealed that both molecules adsorbed as a monolayer to the air–water interface (indicating unfolding of DAMP4 to give a chain of four connected DAMP1 molecules), with a concentration ratio equal to that in the bulk. This suggests the overall free energy of adsorption is equal despite differences in size and bulk structure. At small interfacial extensional strains, only molecule packing influenced the stress response. At larger strains, the effect of size became apparent, with DAMP4 registering a higher stress response and interfacial elasticity. When both components were present at the interface, most stress-dissipating movement was achieved by DAMP1. This work thus provides insights into the role of proteins' molecular size and structure on their interfacial properties, and the designed sequences introduced here can serve as effective tools for interfacial studies of proteins and polymers. PMID:23303222
A Pilot Study to Examine Maturation of Body Temperature Control in Preterm Infants
Knobel, Robin B.; Levy, Janet; Katz, Laurence; Guenther, Bob; Holditch-Davis, Diane
2013-01-01
Objective To test instrumentation and develop analytic models to use in a larger study to examine developmental trajectories of body temperature and peripheral perfusion from birth in extremely low birth weight (EBLW) infants. Design A case study design. Setting The study took place in a level four neonatal intensive care unit (NICU) in North Carolina. Participants Four ELBW infants, less than 29 weeks gestational age at birth. Methods Physiologic data were measured every minute for the first 5 days of life: peripheral perfusion using perfusion index by Masimo and body temperature using thermistors. Body temperature was also measured using infrared thermal imaging. Stimulation and care events were recorded over the first 5 days using video which was coded with Noldus Observer software. Novel analytical models using the state space approach to time series analysis were developed to explore maturation of neural control over central and peripheral body temperature. Results/Conclusion Results from this pilot study confirmed the feasibility of using multiple instruments to measure temperature and perfusion in ELBW infants. This approach added rich data to our case study design and set a clinical context with which to interpret longitudinal physiological data. PMID:24004312
Maximum projection designs for computer experiments
DOE Office of Scientific and Technical Information (OSTI.GOV)
Joseph, V. Roshan; Gul, Evren; Ba, Shan
Space-filling properties are important in designing computer experiments. The traditional maximin and minimax distance designs only consider space-filling in the full dimensional space. This can result in poor projections onto lower dimensional spaces, which is undesirable when only a few factors are active. Restricting maximin distance design to the class of Latin hypercubes can improve one-dimensional projections, but cannot guarantee good space-filling properties in larger subspaces. We propose designs that maximize space-filling properties on projections to all subsets of factors. We call our designs maximum projection designs. As a result, our design criterion can be computed at a cost nomore » more than a design criterion that ignores projection properties.« less
Maximum projection designs for computer experiments
Joseph, V. Roshan; Gul, Evren; Ba, Shan
2015-03-18
Space-filling properties are important in designing computer experiments. The traditional maximin and minimax distance designs only consider space-filling in the full dimensional space. This can result in poor projections onto lower dimensional spaces, which is undesirable when only a few factors are active. Restricting maximin distance design to the class of Latin hypercubes can improve one-dimensional projections, but cannot guarantee good space-filling properties in larger subspaces. We propose designs that maximize space-filling properties on projections to all subsets of factors. We call our designs maximum projection designs. As a result, our design criterion can be computed at a cost nomore » more than a design criterion that ignores projection properties.« less
Patient and public involvement in reducing health and care research waste.
Minogue, Virginia; Cooke, Mary; Donskoy, Anne-Laure; Vicary, Penny; Wells, Bill
2018-01-01
As much as 85 % of health research is believed to be wasted because it is not published or reported, the design is poor or does not consider what is already known in the topic area. Although a great deal of work has been done in the UK to reduce research waste, the role of patients and the public has not been discussed.This paper describes a survey, on the role of patients in reducing research waste, which was carried out as part of a larger piece of work on reducing waste in healthcare. The study found that patients were interested in reducing research waste. The key roles they play in research, for example being co-applicants for funding, members of project teams, co-researchers, means they have some shared responsibility for making sure the quality of research is high. This includes finding out what is already known about a topic and getting the study design right before seeking funding, publishing and reporting the results when the study is finished. Recognising where waste happens is part of good management of a research study. Background Eighty five per cent of health research expenditure is potentially wasted due to failure to publish research, unclear reporting of research that is published, and the failure of new research studies to systematically review previous research in the same topic area, poor study design and conduct. A great deal of progress has been made to address this issue but the role of patients and the public has not been considered. Main A small survey was undertaken, as part of a larger programme of work on reducing health and care waste, to understand the role of patients in reducing research waste. The study showed that patients are interested in this issue particularly in relation to the prioritisation of research and patient and public involvement. Conclusions Patients undertake key roles in the research process including co-applicancy, project management, or as co-researchers. This brings responsibility for ensuring high quality research and value for money. Responsibility for recognition of the potential for wasteful practices is part of the conduct and operation of research studies.
Periscope for noninvasive two-photon imaging of murine retina in vivo
Stremplewski, Patrycjusz; Komar, Katarzyna; Palczewski, Krzysztof; Wojtkowski, Maciej; Palczewska, Grazyna
2015-01-01
Two-photon microscopy allows visualization of subcellular structures in the living animal retina. In previously reported experiments it was necessary to apply a contact lens to each subject. Extending this technology to larger animals would require fitting a custom contact lens to each animal and cumbersome placement of the living animal head on microscope stage. Here we demonstrate a new device, periscope, for coupling light energy into mouse eye and capturing emitted fluorescence. Using this periscope we obtained images of the RPE and their subcellular organelles, retinosomes, with larger field of view than previously reported. This periscope provides an interface with a commercial microscope, does not require contact lens and its design could be modified to image retina in larger animals. PMID:26417507
Surface Enhanced Raman Scattering Monitoring of Chain Alignment in Freely Suspended Nanomembranes
NASA Astrophysics Data System (ADS)
Jiang, Chaoyang; Lio, Wilber Y.; Tsukruk, Vladimir V.
2005-09-01
The molecular chain reorganization in freely standing membranes with encapsulated gold nanoparticles was studied with surface enhanced Raman scattering (SERS) in the course of their elastic deformations. The efficient SERS was enabled by optimizing the design of gold nanoparticle forming chainlike aggregates, thus creating an exceptional ability to conduct in situ monitoring. Small deformations resulted in the radial orientation of side phenyl rings of polymer backbones while larger deflections led to the polymer chains bridging adjacent nanoparticles within one-dimensional aggregates.
Chen, Jiayin; Or, Calvin
2017-11-01
This study assessed the use of an immersive virtual reality (VR), a mouse and a touchscreen for one-directional pointing, multi-directional pointing, and dragging-and-dropping tasks involving targets of smaller and larger widths by young (n = 18; 18-30 years), middle-aged (n = 18; 40-55 years) and older adults (n = 18; 65-75 years). A three-way, mixed-factorial design was used for data collection. The dependent variables were the movement time required and the error rate. Our main findings were that the participants took more time and made more errors in using the VR input interface than in using the mouse or the touchscreen. This pattern applied in all three age groups in all tasks, except for multi-directional pointing with a larger target width among the older group. Overall, older adults took longer to complete the tasks and made more errors than young or middle-aged adults. Larger target widths yielded shorter movement times and lower error rates in pointing tasks, but larger targets yielded higher rates of error in dragging-and-dropping tasks. Our study indicated that any other virtual environments that are similar to those we tested may be more suitable for displaying scenes than for manipulating objects that are small and require fine control. Although interacting with VR is relatively difficult, especially for older adults, there is still potential for older adults to adapt to that interface. Furthermore, adjusting the width of objects according to the type of manipulation required might be an effective way to promote performance. Copyright © 2017 Elsevier Ltd. All rights reserved.
24 CFR 1003.201 - Basic eligible activities.
Code of Federal Regulations, 2011 CFR
2011-04-01
... occupy a designated and discrete area within the larger facility; and (B) The grantee can determine the.... Clearance, demolition, and removal of buildings and improvements, including movement of structures to other...
24 CFR 1003.201 - Basic eligible activities.
Code of Federal Regulations, 2013 CFR
2013-04-01
... occupy a designated and discrete area within the larger facility; and (B) The grantee can determine the.... Clearance, demolition, and removal of buildings and improvements, including movement of structures to other...
24 CFR 1003.201 - Basic eligible activities.
Code of Federal Regulations, 2014 CFR
2014-04-01
... occupy a designated and discrete area within the larger facility; and (B) The grantee can determine the.... Clearance, demolition, and removal of buildings and improvements, including movement of structures to other...
24 CFR 1003.201 - Basic eligible activities.
Code of Federal Regulations, 2012 CFR
2012-04-01
... occupy a designated and discrete area within the larger facility; and (B) The grantee can determine the.... Clearance, demolition, and removal of buildings and improvements, including movement of structures to other...
24 CFR 1003.201 - Basic eligible activities.
Code of Federal Regulations, 2010 CFR
2010-04-01
... occupy a designated and discrete area within the larger facility; and (B) The grantee can determine the.... Clearance, demolition, and removal of buildings and improvements, including movement of structures to other...
Parametric Study of an Ablative TPS and Hot Structure Heatshield for a Mars Entry Capsule Vehicle
NASA Technical Reports Server (NTRS)
Langston, Sarah L.; Lang, Christapher G.; Samareh, Jamshid A.
2017-01-01
The National Aeronautics and Space Administration is planning to send humans to Mars. As part of the Evolvable Mars Campaign, different en- try vehicle configurations are being designed and considered for delivering larger payloads than have been previously sent to the surface of Mars. Mass and packing volume are driving factors in the vehicle design, and the thermal protection for planetary entry is an area in which advances in technology can offer potential mass and volume savings. The feasibility and potential benefits of a carbon-carbon hot structure concept for a Mars entry vehicle is explored in this paper. The windward heat shield of a capsule design is assessed for the hot structure concept as well as an ablative thermal protection system (TPS) attached to a honeycomb sandwich structure. Independent thermal and structural analyses are performed to determine the minimum mass design. The analyses are repeated for a range of design parameters, which include the trajectory, vehicle size, and payload. Polynomial response functions are created from the analysis results to study the capsule mass with respect to the design parameters. Results from the polynomial response functions created from the thermal and structural analyses indicate that the mass of the capsule was higher for the hot structure concept as compared to the ablative TPS for the parameter space considered in this study.
Comparison of inkjet-printed silver conductors on different microsystem substrates
NASA Astrophysics Data System (ADS)
Kruger, Jené; Bezuidenhout, Petroné H.; Joubert, Trudi-Heleen
2016-02-01
Applications for diagnostic and environmental point-of-need require processes and building blocks to add smart features to disposable biosensors on low-cost substrates. A novel method for producing such biosensors is printing electronics using additive technologies. This work contributes to the toolbox of processes, materials and components for printed electronics manufacturing - as well as rapid prototyping - of circuits. Printing protocols were developed to facilitate successful inkjet printing of nanosilver ink (Harima NPS-JL) onto different microsystem substrates using a functional printer (Dimatix DMP-3281). Photo paper is a standard inkjet substrate, which were compared with glass, polycarbonate (PC), plastic projector transparency foil, and polydimethylsiloxane (PDMS). Comparison attributes include physical and electrical properties. The layout design comprised dogbone elements of 8 mm length, and widths varying between 100 μm and 2 mm. All printed features were thermally cured for 1 hour at 120 °C. The physical characteristics were measured with a laser scanning microscope (Zeiss LSM-5) to determine the width, thickness and surface roughness of the printed features. An LCR meter (GW-Instek 8110) was used to measure the printed structures' electrical characteristics (resistance, capacitance and inductance). A lumped element model and layout design rules were extracted to assist in standardized design procedures. The model incorporates prediction of the bandwidth attainable with these structures. The layer thickness on all substrates is larger than the 1 μm on photo paper, and varies between 1.6 μm (PC) and 7 μm (PDMS). The spreading for PDMS is similar to photo paper, but since for the other substrates it is between 5 (glass) and 10 (PC) times larger than for photo paper, the layout design rules require large spacing, leading to larger area networks. Electrical probing on the PDMS is not consistent and results are inconclusive. For the other substrates, the comparative dogbone resistance (100 μm width) is significantly larger than the 2 Ω standard, varying from 12.6 Ω (PC) to 19.3 Ω (glass). The bandwidth relative to photo paper is smaller by a factor of between 6 (PC) and 9.5 (glass).
NASA Astrophysics Data System (ADS)
Stern, Rowena F.; Picard, Kathryn T.; Hamilton, Kristina M.; Walne, Antony; Tarran, Glen A.; Mills, David; McQuatters-Gollop, Abigail; Edwards, Martin
2015-09-01
There is a paucity of data on long-term, spatially resolved changes in microbial diversity and biogeography in marine systems, and yet these organisms underpin fundamental ecological processes in the oceans affecting socio-economic values of the marine environment. We report results from a new autonomous Water and Microplankton Sampler (WaMS) that is carried within the Continuous Plankton Recorder (CPR). Whilst the CPR with its larger mesh size (270 μm), is designed to capture larger plankton, the WaMS was designed as an additional device to capture plankton below 50 μm and delicate larger species, often destroyed by net sampling methods. A 454 pyrosequencing and flow cytometric investigation of eukaryotic microbes using the partial 18S rDNA from thirteen WaMS samples collected over three months in the English Channel revealed a wide diversity of organisms. Alveolates, Fungi, and picoplanktonic Chlorophytes were the most common lineages captured despite the small sample volumes (200-250 ml). The survey also identified Cercozoa and MAST heterotrophic Stramenopiles, normally missed in microscopic-based plankton surveys. The most common was the likely parasitic LKM11 Rozellomycota lineage which comprised 43.2% of all reads and are rarely observed in marine pelagic surveys. An additional 9.5% of reads belonged to other parasitic lineages including marine Syndiniales and Ichthyosporea. Sample variation was considerable, indicating that microbial diversity is spatially or temporally patchy. Our study has shown that the WaMS sampling system is autonomous, versatile and robust, and due to its deployment on the established CPR network, is a cost-effective monitoring tool for microbial diversity for the detection of smaller and delicate taxa.
Participatory interaction design in user requirements specification in healthcare.
Martikainen, Susanna; Ikävalko, Pauliina; Korpela, Mikko
2010-01-01
Healthcare information systems are accused of poor usability even in the popular media in Finland. Doctors especially have been very critical and actively expressed their opinions in public. User involvement and user-centered design methods are seen as the key solution to usability problems. In this paper we describe a research case where participatory methods were experimented within healthcare information systems development in medicinal care in a hospital. The study was part of a larger research project on Activity-driven Information Systems Development in healthcare. The study started by finding out about and modeling the present state of medicinal care in the hospital. After that it was important to define and model the goal state. The goal state, facilitated by the would-be software package, was modeled with the help of user interface drawings as one way of prototyping. Traditional usability methods were extended during the study. According to the health professionals' feedback, the use of participatory and user-centered interaction design methods, particularly user interface drawings enabled them to describe their requirements and create common understanding with the system developers.
Study of large adaptive arrays for space technology applications
NASA Technical Reports Server (NTRS)
Berkowitz, R. S.; Steinberg, B.; Powers, E.; Lim, T.
1977-01-01
The research in large adaptive antenna arrays for space technology applications is reported. Specifically two tasks were considered. The first was a system design study for accurate determination of the positions and the frequencies of sources radiating from the earth's surface that could be used for the rapid location of people or vehicles in distress. This system design study led to a nonrigid array about 8 km in size with means for locating the array element positions, receiving signals from the earth and determining the source locations and frequencies of the transmitting sources. It is concluded that this system design is feasible, and satisfies the desired objectives. The second task was an experiment to determine the largest earthbound array which could simulate a spaceborne experiment. It was determined that an 800 ft array would perform indistinguishably in both locations and it is estimated that one several times larger also would serve satisfactorily. In addition the power density spectrum of the phase difference fluctuations across a large array was measured. It was found that the spectrum falls off approximately as f to the minus 5/2 power.
Engine system assessment study using Martian propellants
NASA Technical Reports Server (NTRS)
Pelaccio, Dennis; Jacobs, Mark; Scheil, Christine; Collins, John
1992-01-01
A top-level feasibility study was conducted that identified and characterized promising chemical propulsion system designs which use two or more of the following propellant combinations: LOX/H2, LOX/CH4, and LOX/CO. The engine systems examined emphasized the usage of common subsystem/component hardware where possible. In support of this study, numerous mission scenarios were characterized that used various combinations of Earth, lunar, and Mars propellants to establish engine system requirements to assess the promising engine system design concept examined, and to determine overall exploration leverage of such systems compared to state-of-the-art cryogenic (LOX/H2) propulsion systems. Initially in the study, critical propulsion system technologies were assessed. Candidate expander and gas generator cycle LOX/H2/CO, LOX/H2/CH4, and LOX/CO/CH4 engine system designs were parametrically evaluated. From this evaluation baseline, tripropellant Mars Transfer Vehicle (MTV) LOX cooled and bipropellant Lunar Excursion Vehicle (LEV) and Mars Excursion Vehicle (MEV) engine systems were identified. Representative tankage designs for a MTV were also investigated. Re-evaluation of the missions using the baseline engine design showed that in general the slightly lower performance, smaller, lower weight gas generator cycle-based engines required less overall mission Mars and in situ propellant production (ISPP) infrastructure support compared to the larger, heavier, higher performing expander cycle engine systems.
Exploration Medical Capability System Engineering Overview
NASA Technical Reports Server (NTRS)
Mindock, J.; McGuire, K.
2018-01-01
Deep Space Gateway and Transport missions will change the way NASA currently practices medicine. The missions will require more autonomous capability compared to current low Earth orbit operations. For the medical system, lack of consumable resupply, evacuation opportunities, and real-time ground support are key drivers toward greater autonomy. Recognition of the limited mission and vehicle resources available to carry out exploration missions motivates the Exploration Medical Capability (ExMC) Element's approach to enabling the necessary autonomy. The ExMC Systems Engineering team's mission is to "Define, develop, validate, and manage the technical system design needed to implement exploration medical capabilities for Mars and test the design in a progression of proving grounds." The Element's work must integrate with the overall exploration mission and vehicle design efforts to successfully provide exploration medical capabilities. ExMC is using Model-Based System Engineering (MBSE) to accomplish its integrative goals. The MBSE approach to medical system design offers a paradigm shift toward greater integration between vehicle and the medical system, and directly supports the transition of Earth-reliant ISS operations to the Earth-independent operations envisioned for Mars. This talk will discuss how ExMC is using MBSE to define operational needs, decompose requirements and architecture, and identify medical capabilities needed to support human exploration. How MBSE is being used to integrate across disciplines and NASA Centers will also be described. The medical system being discussed in this talk is one system within larger habitat systems. Data generated within the medical system will be inputs to other systems and vice versa. This talk will also describe the next steps in model development that include: modeling the different systems that comprise the larger system and interact with the medical system, understanding how the various systems work together, and developing tools to support trade studies.
Exploration Medical Cap Ability System Engineering Overview
NASA Technical Reports Server (NTRS)
McGuire, K.; Mindock, J.
2018-01-01
Deep Space Gateway and Transport missions will change the way NASA currently practices medicine. The missions will require more autonomous capability compared to current low Earth orbit operations. For the medical system, lack of consumable resupply, evacuation opportunities, and real-time ground support are key drivers toward greater autonomy. Recognition of the limited mission and vehicle resources available to carry out exploration missions motivates the Exploration Medical Capability (ExMC) Element's approach to enabling the necessary autonomy. The ExMC Systems Engineering team's mission is to "Define, develop, validate, and manage the technical system design needed to implement exploration medical capabilities for Mars and test the design in a progression of proving grounds." The Element's work must integrate with the overall exploration mission and vehicle design efforts to successfully provide exploration medical capabilities. ExMC is using Model-Based System Engineering (MBSE) to accomplish its integrative goals. The MBSE approach to medical system design offers a paradigm shift toward greater integration between vehicle and the medical system, and directly supports the transition of Earth-reliant ISS operations to the Earth-independent operations envisioned for Mars. This talk will discuss how ExMC is using MBSE to define operational needs, decompose requirements and architecture, and identify medical capabilities needed to support human exploration. How MBSE is being used to integrate across disciplines and NASA Centers will also be described. The medical system being discussed in this talk is one system within larger habitat systems. Data generated within the medical system will be inputs to other systems and vice versa. This talk will also describe the next steps in model development that include: modeling the different systems that comprise the larger system and interact with the medical system, understanding how the various systems work together, and developing tools to support trade studies.
Kushniruk, A; Kaipio, J; Nieminen, M; Hyppönen, H; Lääveri, T; Nohr, C; Kanstrup, A M; Berg Christiansen, M; Kuo, M-H; Borycki, E
2014-08-15
The objective of this paper is to explore approaches to understanding the usability of health information systems at regional and national levels. Several different methods are discussed in case studies from Denmark, Finland and Canada. They range from small scale qualitative studies involving usability testing of systems to larger scale national level questionnaire studies aimed at assessing the use and usability of health information systems by entire groups of health professionals. It was found that regional and national usability studies can complement smaller scale usability studies, and that they are needed in order to understand larger trends regarding system usability. Despite adoption of EHRs, many health professionals rate the usability of the systems as low. A range of usability issues have been noted when data is collected on a large scale through use of widely distributed questionnaires and websites designed to monitor user perceptions of usability. As health information systems are deployed on a widespread basis, studies that examine systems used regionally or nationally are required. In addition, collection of large scale data on the usability of specific IT products is needed in order to complement smaller scale studies of specific systems.
Kaipio, J.; Nieminen, M.; Hyppönen, H.; Lääveri, T.; Nohr, C.; Kanstrup, A. M.; Berg Christiansen, M.; Kuo, M.-H.; Borycki, E.
2014-01-01
Summary Objectives The objective of this paper is to explore approaches to understanding the usability of health information systems at regional and national levels. Methods Several different methods are discussed in case studies from Denmark, Finland and Canada. They range from small scale qualitative studies involving usability testing of systems to larger scale national level questionnaire studies aimed at assessing the use and usability of health information systems by entire groups of health professionals. Results It was found that regional and national usability studies can complement smaller scale usability studies, and that they are needed in order to understand larger trends regarding system usability. Despite adoption of EHRs, many health professionals rate the usability of the systems as low. A range of usability issues have been noted when data is collected on a large scale through use of widely distributed questionnaires and websites designed to monitor user perceptions of usability. Conclusion As health information systems are deployed on a widespread basis, studies that examine systems used regionally or nationally are required. In addition, collection of large scale data on the usability of specific IT products is needed in order to complement smaller scale studies of specific systems. PMID:25123725
PLSS 2.5 Fan Design and Development
NASA Technical Reports Server (NTRS)
Converse, David; Carra, Michael; Quinn, Gregory; Chullen, Cinda
2015-01-01
NASA is building a high fidelity prototype of an advanced portable life support system (PLSS) as part of the Advanced Exploration Systems Program. This new PLSS, designated as PLSS 2.5, will advance component technologies and systems knowledge in order to inform a future flight program. The oxygen ventilation loop of its predecessor, PLSS 2.0, is driven by a centrifugal fan developed using specifications from over five years ago. PLSS technology and system parameters have matured to the point where the existing fan will not perform adequately for the new prototype. In addition, areas of potential improvement have been identified with the existing fan that could be addressed in a new design. As a result, a new fan was designed and tested for the PLSS 2.5. The PLSS 2.5 fan is a derivative of the one used in PLSS 2.0. It uses the same basic non-metallic can around the motor, but with a larger volute and impeller to meet the higher pressure drop requirements of the PLSS 2.5 loop. This allows it to operate at rotational speeds that are matched to rolling element bearings, and which create reasonably low impeller tip speeds. Development of the fan also considered a shrouded impeller design that allows larger clearances for greater oxygen safety and better performance.
McCann, Russell A; Armstrong, Christina M; Skopp, Nancy A; Edwards-Stewart, Amanda; Smolenski, Derek J; June, Jennifer D; Metzger-Abamukong, Melinda; Reger, Greg M
2014-08-01
Randomized controlled trials (RCTs) support the effectiveness of virtual reality exposure therapy (VRET) for anxiety disorders; however, the overall quality of the VRET RCT literature base has yet to be evaluated. This study reviewed 27 VRET RCTs and the degree of adherence to 8 RCT research design criteria derived from existing standards. Adherence to the study quality criteria was generally low as the articles met an average 2.85 criteria (SD=1.56). None of the studies met more than six quality criteria. Study quality did not predict effect size; however, a reduction in effect size magnitude was observed for studies with larger sample sizes when comparing VRET to non-active control groups. VRET may be an effective method of treatment but caution should be exercised in interpreting the existing body of literature supporting VRET relative to existing standards of care. The need for well-designed VRET research is discussed. Copyright © 2014. Published by Elsevier Ltd.
Scanning Probe Microscopies and Their Applications Towards the Study of Superconductors
NASA Astrophysics Data System (ADS)
Helfrich, Jennifer Ann
1995-11-01
The invention of the scanning tunneling microscope (STM) in 1982 made it possible to study surfaces and structures at resolutions previously believed unattainable. Adapting the STM for low temperatures makes it possible to study superconductors with new methods and to obtain valuable information. This thesis describes a novel low temperature STM (LTSTM) that was designed and built at Northwestern University for the purpose of studying superconductors in the mixed state. At low temperatures, this LTSTM has a scan range an order of magnitude larger than other LTSTM's designed elsewhere. It is capable of low temperature imaging and obtaining dI/dV vs. V curves. A detailed study of magnetic force microscopy (MFM) probes is also presented. The fields and forces between probe and surface were computer modeled. These results are compared with results from electron holographs of MFM probes. The final section of the thesis describes an a.c. susceptibility measurement on a UPt_3 sphere. Results are presented and discussed.
Stringer, Barbara; van Meijel, Berno; Karman, Pieter; Koekkoek, Bauke; Hoogendoorn, Adriaan W; Kerkhof, Ad J F M; Beekman, Aartjan T F
2015-07-01
To test if a collaborative care program (CCP) with nurses in a coordinating position is beneficial for patients with severe personality disorders. A pilot study with a comparative multiple case study design using mixed methods investigating active ingredients and preliminary results. Most patients, their informal caregivers, and nurses value (parts of) the CCP positively; preliminary results show a significant decrease in severity of borderline symptoms. With the CCP, we may expand the supply of available treatments for patients with (severe) personality disorders, but a larger randomized controlled trial is warranted to confirm our preliminary results. © 2014 Wiley Periodicals, Inc.
Code IN Exhibits - Supercomputing 2000
NASA Technical Reports Server (NTRS)
Yarrow, Maurice; McCann, Karen M.; Biswas, Rupak; VanderWijngaart, Rob F.; Kwak, Dochan (Technical Monitor)
2000-01-01
The creation of parameter study suites has recently become a more challenging problem as the parameter studies have become multi-tiered and the computational environment has become a supercomputer grid. The parameter spaces are vast, the individual problem sizes are getting larger, and researchers are seeking to combine several successive stages of parameterization and computation. Simultaneously, grid-based computing offers immense resource opportunities but at the expense of great difficulty of use. We present ILab, an advanced graphical user interface approach to this problem. Our novel strategy stresses intuitive visual design tools for parameter study creation and complex process specification, and also offers programming-free access to grid-based supercomputer resources and process automation.
2016-06-01
Development of a new design methodology for structural airfield mats. International Journal of Pavement Research and Tech- nology 3(3):102-109...load exerted by aircraft over a larger area. Six airfield matting systems of varying materials and designs were evaluated through the construction...position unless so designated by other authorized documents. DESTROY THIS REPORT WHEN NO LONGER NEEDED. DO NOT RETURN IT TO THE ORIGINATOR. ERDC/GSL
2013-05-23
This monograph borrows from multiple disciplines to argue for an organizational shift from process reengineering to system design to improve...government customer-service delivery. Specifically, the monograph proposes a transformation in claims processing within the Veterans Benefits Administration...required. The proposed system design is an attempt to place the disability claims process within a larger environment encompassing multiple dimensions of customers.
Nanostructure enhanced ionic transport in fullerene reinforced solid polymer electrolytes.
Sun, Che-Nan; Zawodzinski, Thomas A; Tenhaeff, Wyatt E; Ren, Fei; Keum, Jong Kahk; Bi, Sheng; Li, Dawen; Ahn, Suk-Kyun; Hong, Kunlun; Rondinone, Adam J; Carrillo, Jan-Michael Y; Do, Changwoo; Sumpter, Bobby G; Chen, Jihua
2015-03-28
Solid polymer electrolytes, such as polyethylene oxide (PEO) based systems, have the potential to replace liquid electrolytes in secondary lithium batteries with flexible, safe, and mechanically robust designs. Previously reported PEO nanocomposite electrolytes routinely use metal oxide nanoparticles that are often 5-10 nm in diameter or larger. The mechanism of those oxide particle-based polymer nanocomposite electrolytes is under debate and the ion transport performance of these systems is still to be improved. Herein we report a 6-fold ion conductivity enhancement in PEO/lithium bis(trifluoromethanesulfonyl) imide (LiTFSI)-based solid electrolytes upon the addition of fullerene derivatives. The observed conductivity improvement correlates with nanometer-scale fullerene crystallite formation, reduced crystallinities of both the (PEO)6:LiTFSI phase and pure PEO, as well as a significantly larger PEO free volume. This improved performance is further interpreted by enhanced decoupling between ion transport and polymer segmental motion, as well as optimized permittivity and conductivity in bulk and grain boundaries. This study suggests that nanoparticle induced morphological changes, in a system with fullerene nanoparticles and no Lewis acidic sites, play critical roles in their ion conductivity enhancement. The marriage of fullerene derivatives and solid polymer electrolytes opens up significant opportunities in designing next-generation solid polymer electrolytes with improved performance.
Role of urban surface roughness in road-deposited sediment build-up and wash-off
NASA Astrophysics Data System (ADS)
Zhao, Hongtao; Jiang, Qian; Xie, Wenxia; Li, Xuyong; Yin, Chengqing
2018-05-01
Urban road surface roughness is one of the most important factors in estimation of surface runoff loads caused by road-deposited sediment (RDS) wash-off and design of its control measures. However, because of a lack of experimental data to distinguish the role of surface roughness, the effects of surface roughness on RDS accumulation and release are not clear. In this study, paired asphalt and concrete road surfaces and rainfall simulation designs were used to distinguish the role of surface roughness in RDS build-up and wash-off. Our results showed that typical asphalt surfaces often have higher depression depths than typical concrete surfaces, indicating that asphalt surfaces are relatively rougher than concrete surface. Asphalt surfaces can retain a larger RDS amount, relative higher percentage of coarser particles, larger RDS wash-off loads, and lower wash-off percentage, than concrete surfaces. Surface roughness has different effects in RDS motilities with different particle sizes during rainfall runoff, and the settleable particles (44-149 μm) were notably influenced by it. Furthermore, the first flush phenomenon tended to be greater on relatively smooth surfaces than relatively rough surfaces. Overall, surface roughness plays an important role in influencing the complete process of RDS build-up and wash-off on different road characteristics.
Advanced Optics for a Full Quasi-Optical Front Steering ECRH Upper Launcher for ITER
DOE Office of Scientific and Technical Information (OSTI.GOV)
Moro, A.; Alessi, E.; Bruschi, A.
2009-11-26
A full quasi-optical setup for the internal optics of the Front Steering Electron Cyclotron Resonance Heating (ECRH) Upper Launcher for ITER was designed, proving to be feasible and favorable in terms of additional flexibility and cost reduction with respect to the former design. This full quasi-optical solution foresees the replacement of the mitre-bends in the final section of the launcher with dedicated free-space mirrors to realize the last changes of directions in the launcher. A description of the launcher is given and its advantages presented. The parameters of the expected output beams as well as preliminary evaluations of truncation effectsmore » with the physical optics GRASP code are shown. Moreover, a study of mitre-bends replacement with single mirrors for multiple beams is described. In principle it could allow the beams to be larger at the mirror locations (with a further decrease of the peak power density due to partial overlapping) and has the additional advantage to get a larger opening with compressed beams to avoid conflicts with side-walls port. Constraints on the setup, arising both from the resulting beam characteristics in the space of free parameters and from mechanical requirements are taken into account in the analysis.« less
Geometrical tile design for complex neighborhoods.
Czeizler, Eugen; Kari, Lila
2009-01-01
Recent research has showed that tile systems are one of the most suitable theoretical frameworks for the spatial study and modeling of self-assembly processes, such as the formation of DNA and protein oligomeric structures. A Wang tile is a unit square, with glues on its edges, attaching to other tiles and forming larger and larger structures. Although quite intuitive, the idea of glues placed on the edges of a tile is not always natural for simulating the interactions occurring in some real systems. For example, when considering protein self-assembly, the shape of a protein is the main determinant of its functions and its interactions with other proteins. Our goal is to use geometric tiles, i.e., square tiles with geometrical protrusions on their edges, for simulating tiled paths (zippers) with complex neighborhoods, by ribbons of geometric tiles with simple, local neighborhoods. This paper is a step toward solving the general case of an arbitrary neighborhood, by proposing geometric tile designs that solve the case of a "tall" von Neumann neighborhood, the case of the f-shaped neighborhood, and the case of a 3 x 5 "filled" rectangular neighborhood. The techniques can be combined and generalized to solve the problem in the case of any neighborhood, centered at the tile of reference, and included in a 3 x (2k + 1) rectangle.
ERIC Educational Resources Information Center
Fiene, Karen; Sabbatini, Robert
2011-01-01
How do forward-looking institutions with rich landscape and architectural heritages integrate contemporary programming and design? This article explores the evolution of the Mills College campus and compares it with two larger western universities: the University of California, Berkeley (UCB) and Leland Stanford, Jr., University (Stanford…
Integrated Design of a Telerobotic Workstation
NASA Technical Reports Server (NTRS)
Rochlis, Jennifer L.; Clarke, John-Paul
2001-01-01
The experiments described in this paper are part of a larger joint MIT/NASA research effort that focuses on the development of a methodology for designing and evaluating integrated interfaces for highly dexterous and multi-functional telerobots. Specifically, a telerobotic workstation is being designed for an Extravehicular Activity (EVA) anthropomorphic space station telerobot. Previous researchers have designed telerobotic workstations based upon performance of discrete subsets of tasks (for example, peg-in-hole, tracking, etc.) without regard for transitions that operators go through between tasks performed sequentially in the context of larger integrated tasks. The exploratory research experiments presented here took an integrated approach and assessed how subjects operating a full-immersion telerobot perform during the transitions between sub-tasks of two common EVA tasks. Preliminary results show that up to 30% of total task time is spent gaining and maintaining Situation Awareness (SA) of their task space and environment during transitions. Although task performance improves over the two trial days, the percentage of time spent on SA remains the same. This method identifies areas where workstation displays and feedback mechanisms are most needed to increase operator performance and decrease operator workload - areas that previous research methods have not been able to address.
Refined Gearbox Design for the Chariot Lunar Rover
NASA Technical Reports Server (NTRS)
Bauman, Steve; Lewicki, David
2010-01-01
In planning for NASA's return to the moon by the year 2020, the NASA Johnson Space Center (JSC) designed and built a lunar concept vehicle called Chariot. Slightly larger than a pickup truck, it was designed to demonstrate similar utilitarian functions, but with twelve wheels for redundancy, reliability, and reduced surface contact pressure. JSC designed a motor gearbox to drive each of Chariot s six wheel pods. The pods can be independently steered over 360 for maneuverability. This paper describes the design of a second generation, drop-in replacement gearbox. The new design has a lower parts count, and is lighter than the original, which represents a step toward flight hardware.
Fay, Lindsey; Carll-White, Allison; Schadler, Aric; Isaacs, Kathy B; Real, Kevin
2017-10-01
The focus of this research was to analyze the impact of decentralized and centralized hospital design layouts on the delivery of efficient care and the resultant level of caregiver satisfaction. An interdisciplinary team conducted a multiphased pre- and postoccupancy evaluation of a cardiovascular service line in an academic hospital that moved from a centralized to decentralized model. This study examined the impact of walkability, room usage, allocation of time, and visibility to better understand efficiency in the care environment. A mixed-methods data collection approach was utilized, which included pedometer measurements of staff walking distances, room usage data, time studies in patient rooms and nurses' stations, visibility counts, and staff questionnaires yielding qualitative and quantitative results. Overall, the data comparing the centralized and decentralized models yielded mixed results. This study's centralized design was rated significantly higher in its ability to support teamwork and efficient patient care with decreased staff walking distances. The decentralized unit design was found to positively influence proximity to patients in a larger design footprint and contribute to increased visits to and time spent in patient rooms. Among the factors contributing to caregiver efficiency and satisfaction are nursing station design, an integrated team approach, and the overall physical layout of the space on walkability, allocation of caregiver time, and visibility. However, unit design alone does not solely impact efficiency, suggesting that designers must consider the broader implications of a culture of care and processes.
Ambrosini, Emilia; Ferrante, Simona; Schauer, Thomas; Ferrigno, Giancarlo; Molteni, Franco; Pedrocchi, Alessandra
2010-08-01
This study deals with the design of a controller for cycling induced by functional electrical stimulation. The controller will be exploitable in the rehabilitation of hemiparetic patients who need to recover motor symmetry. It uses the pulse width as the control variable in the stimulation of the two legs in order to nullify the unbalance between the torques produced at the two crank arms. It was validated by means of isokinetic trials performed both by healthy subjects and stroke patients. The results showed that the controller was able to reach, and then maintain, a symmetrical pedaling. In the future, the controller will be validated on a larger number of stroke patients.
Quench Protection of SC Quadrupole Magnets
NASA Astrophysics Data System (ADS)
Feher, S.; Bossert, R.; Dimarco, J.; Mitchell, D.; Lamm, M. J.; Limon, P. J.; Mazur, P.; Nobrega, F.; Orris, D.; Ozelis, J. P.; Strait, J. B.; Tompkins, J. C.; Zlobin, A. V.; McInturff, A. D.
1997-05-01
The energy stored in a superconducting accelerator magnet is dissipated after a quench in the coil normal zones, heating the coil and generating a turn to turn and coil to ground voltage drop. Quench heaters are used to protect the superconducting magnet by greatly increasing the coil normal zone thus allowing the energy to be dissipated over a larger conductor volume. Such heaters will be required for the Fermilab/LBNL design of the high gradient quads (HGQ) designed for the LHC interaction regions. As a first step, heaters were installed and tested in several Tevatron low-β superconducting quadrupoles. Experimental studies in normal and superfluid helium are presented which show the heater-induced quench response as a function of magnet excitation current, magnet temperature and peak heater energy density.
Reference aircraft for ICAO Working Group E
NASA Technical Reports Server (NTRS)
1978-01-01
The results of an advanced supersonic transport aircraft/engine integration study to be used as a detail preliminary design case to assist in the assessment of noise standards applicable to future supersonic transports are summarized. The design considered reflects the application of the advanced technologies which are projected to be available for program initiation in the 1980-1985 time period. Suppression characteristics included were obtained in simulated forward flight in the Rolls-Royce spin rig using a small scale model. The engine size selected produces a noise no greater than 108 EPNdB at any of the three Far Part 36 (Stage 2) defined measuring points and is sized slightly larger than the optimum cruise size to meet this noise constraint condition.
Marine biomass: New York state species and site studies. Annual report 1 Dec 80-30 Nov 81
DOE Office of Scientific and Technical Information (OSTI.GOV)
Squires, D.F.; McKay, L.; Brinkhuis, B.
1982-03-01
Nine species of indigenous New York seaweeds were surveyed for potential as feedstock for methanogenesis. Preliminary data from raft culture experiments suggest that some species' yields may be higher in the field than in the laboratory. Important technical gains were made in affixing attached-growth-mode species to substrates. Sites for use in larger scale experimental structures around Long Island were evaluated for their environmental and use-conflict parameters. Five novel biomass farm designs were engineered and tested by computer models for survivability. Several of the evaluated designs have been or will be constructed. Novel mooring, anchoring and wave-dampening devices were also consideredmore » in this phase of work.« less
Hertzmann, Leezah; Target, Mary; Hewison, David; Casey, Polly; Fearon, Pasco; Lassri, Dana
2016-12-01
To explore the effectiveness of a mentalization-based therapeutic intervention specifically developed for parents in entrenched conflict over their children. To the best of our knowledge, this is the first randomized controlled intervention study in the United Kingdom to work with both parents postseparation, and the first to focus on mentalization in this situation. Using a mixed-methods study design, 30 parents were randomly allocated to either mentalization-based therapy for parental conflict-Parenting Together, or the Parents' Group, a psycho-educational intervention for separated parents based on elements of the Separated Parents Information Program-part of the U.K. Family Justice System and approximating to treatment as usual. Given the challenges of recruiting parents in these difficult circumstances, the sample size was small and permitted only the detection of large differences between conditions. The data, involving repeated measures of related individuals, was explored statistically, using hierarchical linear modeling, and qualitatively. Significant findings were reported on the main predicted outcomes, with clinically important trends on other measures. Qualitative findings further contributed to the understanding of parents' subjective experience, pre- and posttreatment. Findings indicate that a larger scale randomized controlled trial would be worthwhile. These encouraging findings shed light on the dynamics maintaining these high-conflict situations known to be damaging to children. We established that both forms of intervention were acceptable to most parents, and we were able to operate a random allocation design with extensive quantitative and qualitative assessments of the kind that would make a larger-scale trial feasible and productive. (PsycINFO Database Record (c) 2016 APA, all rights reserved).
NASA Astrophysics Data System (ADS)
Gómez, Walter; Chávez, Carlos; Salgado, Hugo; Vásquez, Felipe
2017-11-01
We present the design, implementation, and evaluation of a subsidy program to introduce cleaner and more efficient household wood combustion technologies. The program was conducted in the city of Temuco, one of the most polluted cities in southern Chile, as a pilot study to design a new national stove replacement initiative for pollution control. In this city, around 90% of the total emissions of suspended particulate matter is caused by households burning wood. We created a simulated market in which households could choose among different combustion technologies with an assigned subsidy. The subsidy was a relevant factor in the decision to participate, and the inability to secure credit was a significant constraint for the participation of low-income households. Due to several practical difficulties and challenges associated with the implementation of large-scale programs that encourage technological innovation at the household level, it is strongly advisable to start with a small-scale pilot that can provide useful insights into the final design of a fuller, larger-scale program.
NASA Technical Reports Server (NTRS)
Roffe, G.; Venkataramani, K. S.
1978-01-01
Emissions of NOx, CO, and unburned hydrocarbons (UHC) are reported for a lean premixed propane-air system at inlet conditions of 800K and 1MPa using twelve flameholder designs. The flameholders tested represent six design concepts with two values of blockage for each concept. Data were obtained at reference velocities of 35 m/s, 25 m/s and 20 m/s at combustor stations 10 cm and 30 cm downstream of the flameholders. Flameholder pressure drop was found to be a principal determinant of emissions performance. Designs producing larger pressure drops also produced less NOx, CO, and UHC emissions. The lean stability limit equivalence ratio was found to be approximately 0.35 for all designs. Flashback velocities (axial components in the flameholder passages) varied between 30 m/s and 40 m/s. A perforated plate flameholder was operated with a velocity as low as 23 m/s through the perforations at equivalence ratio 0.7 without producing flashback.
Large-area field-ionization detector for the study of Rydberg atoms.
Jones, A C L; Piñeiro, A M; Roeder, E E; Rutbeck-Goldman, H J; Tom, H W K; Mills, A P
2016-11-01
We describe here the development and characterization of a micro-channel plate (MCP) based detector designed for the efficient collection and detection of Rydberg positronium (Ps) atoms for use in a time-of-flight apparatus. The designed detector collects Rydberg atoms over a large area (∼4 times greater than the active area of the MCP), ionizing incident atoms and then collecting and focusing the freed positrons onto the MCP. Here we discuss the function, design, and optimization of the device. The detector has an efficiency for Rydberg Ps that is two times larger than that of the γ-ray scintillation detector based scheme it has been designed to replace, with half the background signal. In principle, detectors of the type described here could be readily employed for the detection of any Rydberg atom species, provided a sufficient field can be applied to achieve an ionization rate of ≥10 8 /s. In such cases, the best time resolution would be achieved by collecting ionized electrons rather than the positive ions.
Optical design of ultrashort throw liquid crystal on silicon projection system
NASA Astrophysics Data System (ADS)
Huang, Jiun-Woei
2017-05-01
An ultrashort throw liquid crystal on silicon (LCoS) projector for home cinema, virtual reality, and automobile heads-up display has been designed and fabricated. To achieve the best performance and highest-quality image, this study aimed to design wide-angle projection optics and optimize the illumination for LCoS. Based on the telecentric lens projection system and optimized Koehler illumination, the optical parameters were calculated. The projector's optical system consisted of a conic aspheric mirror and image optics using either symmetric double Gauss or a large-angle eyepiece to achieve a full projection angle larger than 155 deg. By applying Koehler illumination, image resolution was enhanced and the modulation transfer function of the image in high spatial frequency was increased to form a high-quality illuminated image. The partial coherence analysis verified that the design was capable of 2.5 lps/mm within a 2 m×1.5 m projected image. The throw ratio was less than 0.25 in HD format.
Factors of U.S. Hospitals Associated with Improved Profit Margins: An Observational Study.
Ly, Dan P; Cutler, David M
2018-02-14
Hospitals face financial pressure from decreased margins from Medicare and Medicaid and lower reimbursement from consolidating insurers. The objectives of this study are to determine whether hospitals that became more profitable increased revenues or decreased costs more and to examine characteristics associated with improved financial performance over time. The design of this study is retrospective analyses of U.S. non-federal acute care hospitals between 2003 and 2013. There are 2824 hospitals as subjects of this study. The main measures of this study are the change in clinical operating margin, change in revenues per bed, and change in expenses per bed between 2003 and 2013. Hospitals that became more profitable had a larger magnitude of increases in revenue per bed (about $113,000 per year [95% confidence interval: $93,132 to $133,401]) than of decreases in costs per bed (about - $10,000 per year [95% confidence interval: - $28,956 to $9617]), largely driven by higher non-Medicare reimbursement. Hospitals that improved their margins were larger or joined a hospital system. Not-for-profit status was associated with increases in operating margin, while rural status and having a larger share of Medicare patients were associated with decreases in operating margin. There was no association between improved hospital profitability and changes in diagnosis related group weight, in number of profitable services, or in payer mix. Hospitals that became more profitable were more likely to increase their admissions per bed per year. Differential price increases have led to improved margins for some hospitals over time. Where significant price increases are not possible, hospitals will have to become more efficient to maintain profitability.
Electricity Market Manipulation: How Behavioral Modeling Can Help Market Design
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gallo, Giulia
The question of how to best design electricity markets to integrate variable and uncertain renewable energy resources is becoming increasingly important as more renewable energy is added to electric power systems. Current markets were designed based on a set of assumptions that are not always valid in scenarios of high penetrations of renewables. In a future where renewables might have a larger impact on market mechanisms as well as financial outcomes, there is a need for modeling tools and power system modeling software that can provide policy makers and industry actors with more realistic representations of wholesale markets. One optionmore » includes using agent-based modeling frameworks. This paper discusses how key elements of current and future wholesale power markets can be modeled using an agent-based approach and how this approach may become a useful paradigm that researchers can employ when studying and planning for power systems of the future.« less
Study, optimization, and design of a laser heat engine. [for satellite applications
NASA Technical Reports Server (NTRS)
Taussig, R. T.; Cassady, P. E.; Zumdieck, J. F.
1978-01-01
Laser heat engine concepts, proposed for satellite applications, are analyzed to determine which engine concept best meets the requirements of high efficiency (50 percent or better), continuous operation in space using near-term technology. The analysis of laser heat engines includes the thermodynamic cycles, engine design, laser power sources, collector/concentrator optics, receiving windows, absorbers, working fluids, electricity generation, and heat rejection. Specific engine concepts, optimized according to thermal efficiency, are rated by their technological availability and scaling to higher powers. A near-term experimental demonstration of the laser heat engine concept appears feasible utilizing an Otto cycle powered by CO2 laser radiation coupled into the engine through a diamond window. Higher cycle temperatures, higher efficiencies, and scalability to larger sizes appear to be achievable from a laser heat engine design based on the Brayton cycle and powered by a CO laser.
Herring, R. Patti; Butler, Terry; Hall, Sonja; Montgomery, Susanne B.; Fraser, Gary E.
2011-01-01
Objective The goal of the prospective Adventist Health Study-2 (AHS-2) was to examine the relationship between diet and risk of breast, prostate and colon cancers in Black and White participants. This paper describes the study design, recruitment methods, response rates, and characteristics of Blacks in the AHS-2, thus providing insights about effective strategies to recruit Blacks to participate in research studies. Design We designed a church-based recruitment model and trained local recruiters who used various strategies to recruit participants in their churches. Participants completed a 50-page self-administered dietary and lifestyle questionnaire. Participants Participants are Black Seventh-day Adventists, aged 30–109 years, and members of 1,209 Black churches throughout the United States and Canada. Results Approximately 48,328 Blacks from an estimated target group of over 90,000 signed up for the study and 25,087 completed the questionnaire, comprising about 26% of the larger 97,000 AHS-2-member cohort. Participants were diverse in age, geographic location, education, and income. Seventy percent were female with a median age of 59 years. Conclusion In spite of many recruitment challenges and barriers, we successfully recruited a large cohort whose data should provide some answers as to why Blacks have poorer health outcomes than several other ethnic groups, and help explain existing health disparities. PMID:21305834
NASA Astrophysics Data System (ADS)
Ferrini, Silvia; Schaafsma, Marije; Bateman, Ian
2014-06-01
Benefit transfer (BT) methods are becoming increasingly important for environmental policy, but the empirical findings regarding transfer validity are mixed. A novel valuation survey was designed to obtain both stated preference (SP) and revealed preference (RP) data concerning river water quality values from a large sample of households. Both dichotomous choice and payment card contingent valuation (CV) and travel cost (TC) data were collected. Resulting valuations were directly compared and used for BT analyses using both unit value and function transfer approaches. WTP estimates are found to pass the convergence validity test. BT results show that the CV data produce lower transfer errors, below 20% for both unit value and function transfer, than TC data especially when using function transfer. Further, comparison of WTP estimates suggests that in all cases, differences between methods are larger than differences between study areas. Results show that when multiple studies are available, using welfare estimates from the same area but based on a different method consistently results in larger errors than transfers across space keeping the method constant.
Does Goal Relevant Episodic Future Thinking Amplify the Effect on Delay Discounting?
O’Donnell, Sara; Daniel, Tinuke Oluyomi; Epstein, Leonard H.
2017-01-01
Delay discounting (DD) is the preference for smaller immediate rewards over larger delayed rewards. Research shows episodic future thinking (EFT), or mentally simulating future experiences, reframes the choice between small immediate and larger delayed rewards, and can reduce DD. Only general EFT has been studied, whereby people reframe decisions in terms of non-goal related future events. Since future thinking is often goal-oriented and leads to greater activation of brain regions involved in prospection, goal-oriented EFT may be associated with greater reductions in DD than general goal-unrelated EFT. The present study (n = 104, Mage = 22.25, SD = 3.42; 50% Female) used a between-subjects 2×2 factorial design with type of episodic thinking (Goal, General) and temporal perspective (Episodic future versus recent thinking; EFT vs ERT) as between factors. Results showed a significant reduction in DD for EFT groups (p < 0.001, Cohen’s d effect size = 0.89), and goal-EFT was more effective than general-EFT on reducing DD (p = 0.03, d = 0.64). PMID:28282631
Does goal relevant episodic future thinking amplify the effect on delay discounting?
O'Donnell, Sara; Oluyomi Daniel, Tinuke; Epstein, Leonard H
2017-05-01
Delay discounting (DD) is the preference for smaller immediate rewards over larger delayed rewards. Research shows episodic future thinking (EFT), or mentally simulating future experiences, reframes the choice between small immediate and larger delayed rewards, and can reduce DD. Only general EFT has been studied, whereby people reframe decisions in terms of non-goal related future events. Since future thinking is often goal-oriented and leads to greater activation of brain regions involved in prospection, goal-oriented EFT may be associated with greater reductions in DD than general goal-unrelated EFT. The present study (n=104, M age =22.25, SD=3.42; 50% Female) used a between-subjects 2×2 factorial design with type of episodic thinking (Goal, General) and temporal perspective (Episodic future versus recent thinking; EFT vs ERT) as between factors. Results showed a significant reduction in DD for EFT groups (p<0.001, Cohen's d effect size=0.89), and goal-EFT was more effective than general-EFT on reducing DD (p=0.03, d=0.64). Copyright © 2017 Elsevier Inc. All rights reserved.
First-principles analysis of ferroelectric transition in MnSnO3 and MnTiO3 perovskites
NASA Astrophysics Data System (ADS)
Kang, Sung Gu
2018-06-01
The ferroelectric instabilities of an artificially adopted Pnma structure in low tolerance perovskites have been explored (Kang et al., 2017) [4], where an unstable A-site environment was reported to be the major driving source for the low tolerance perovskites to exhibit ferroelectric instability. This study examined the ferroelectric transition of two magnetic perovskite materials, MnSnO3 and MnTiO3, in Pnma phase. Phase transitions to the Pnma phase at elevated pressures were observed. MnSnO3, which has a lower (larger) tolerance factor (B-site cation radius), showed a higher ferroelectric mode amplitude than MnTiO3. The distribution of the bond length of Mn-O and the mean quadratic elongation (QE) of octahedra (SnO6 or TiO6) were investigated for structural analysis. However, MnTiO3 showed a larger spontaneous polarization than MnSnO3 due to high Born effective charges of titanium. This study is useful because it provides a valuable pathway to the design of promising multiferroic materials.
Best Bang for the Buck: Part 2 – Choosing Between Different Sized Designs
Anderson-Cook, Christine Michaela; Lu, Lu
2016-11-01
Last month, we considered four potential designs of varying sizes and a variety of their attributes for an engineering problem involving a screening design with seven factors. The engineer’s original request was to find a design with 14 runs that could estimate all of the main effects, as well as have some potential for finding important two-factor interactions and possibly curvature in the underlying surface. This assessment was that the proposed size of design was potentially a bit too ambitious for the experiment’s goals, so we explored three other competing designs that had slightly larger sizes but were able tomore » improve several aspects of the design.« less
Best Bang for the Buck: Part 2 – Choosing Between Different Sized Designs
DOE Office of Scientific and Technical Information (OSTI.GOV)
Anderson-Cook, Christine Michaela; Lu, Lu
Last month, we considered four potential designs of varying sizes and a variety of their attributes for an engineering problem involving a screening design with seven factors. The engineer’s original request was to find a design with 14 runs that could estimate all of the main effects, as well as have some potential for finding important two-factor interactions and possibly curvature in the underlying surface. This assessment was that the proposed size of design was potentially a bit too ambitious for the experiment’s goals, so we explored three other competing designs that had slightly larger sizes but were able tomore » improve several aspects of the design.« less
Mysid (Mysidopsis bahia) life-cycle test: Design comparisons and assessment
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lussier, S.M.; Champlin, D.; Kuhn, A.
1996-12-31
This study examines ASTM Standard E1191-90, ``Standard Guide for Conducting Life-cycle Toxicity Tests with Saltwater Mysids,`` 1990, using Mysidopsis bahia, by comparing several test designs to assess growth, reproduction, and survival. The primary objective was to determine the most labor efficient and statistically powerful test design for the measurement of statistically detectable effects on biologically sensitive endpoints. Five different test designs were evaluated varying compartment size, number of organisms per compartment and sex ratio. Results showed that while paired organisms in the ASTM design had the highest rate of reproduction among designs tested, no individual design had greater statistical powermore » to detect differences in reproductive effects. Reproduction was not statistically different between organisms paired in the ASTM design and those with randomized sex ratios using larger test compartments. These treatments had numerically higher reproductive success and lower within tank replicate variance than treatments using smaller compartments where organisms were randomized, or had a specific sex ratio. In this study, survival and growth were not statistically different among designs tested. Within tank replicate variability can be reduced by using many exposure compartments with pairs, or few compartments with many organisms in each. While this improves variance within replicate chambers, it does not strengthen the power of detection among treatments in the test. An increase in the number of true replicates (exposure chambers) to eight will have the effect of reducing the percent detectable difference by a factor of two.« less
New nonbinary quantum codes with larger distance constructed from BCH codes over 𝔽q2
NASA Astrophysics Data System (ADS)
Xu, Gen; Li, Ruihu; Fu, Qiang; Ma, Yuena; Guo, Luobin
2017-03-01
This paper concentrates on construction of new nonbinary quantum error-correcting codes (QECCs) from three classes of narrow-sense imprimitive BCH codes over finite field 𝔽q2 (q ≥ 3 is an odd prime power). By a careful analysis on properties of cyclotomic cosets in defining set T of these BCH codes, the improved maximal designed distance of these narrow-sense imprimitive Hermitian dual-containing BCH codes is determined to be much larger than the result given according to Aly et al. [S. A. Aly, A. Klappenecker and P. K. Sarvepalli, IEEE Trans. Inf. Theory 53, 1183 (2007)] for each different code length. Thus families of new nonbinary QECCs are constructed, and the newly obtained QECCs have larger distance than those in previous literature.
NASA Technical Reports Server (NTRS)
Yarrow, Maurice; McCann, Karen M.; Biswas, Rupak; VanderWijngaart, Rob; Yan, Jerry C. (Technical Monitor)
2000-01-01
The creation of parameter study suites has recently become a more challenging problem as the parameter studies have now become multi-tiered and the computational environment has become a supercomputer grid. The parameter spaces are vast, the individual problem sizes are getting larger, and researchers are now seeking to combine several successive stages of parameterization and computation. Simultaneously, grid-based computing offers great resource opportunity but at the expense of great difficulty of use. We present an approach to this problem which stresses intuitive visual design tools for parameter study creation and complex process specification, and also offers programming-free access to grid-based supercomputer resources and process automation.
Brain Stimulation in Alzheimer's Disease.
Chang, Chun-Hung; Lane, Hsien-Yuan; Lin, Chieh-Hsin
2018-01-01
Brain stimulation techniques can modulate cognitive functions in many neuropsychiatric diseases. Pilot studies have shown promising effects of brain stimulations on Alzheimer's disease (AD). Brain stimulations can be categorized into non-invasive brain stimulation (NIBS) and invasive brain stimulation (IBS). IBS includes deep brain stimulation (DBS), and invasive vagus nerve stimulation (VNS), whereas NIBS includes transcranial magnetic stimulation (TMS), transcranial direct current stimulation (tDCS), transcranial alternating current stimulation (tACS), electroconvulsive treatment (ECT), magnetic seizure therapy (MST), cranial electrostimulation (CES), and non-invasive VNS. We reviewed the cutting-edge research on these brain stimulation techniques and discussed their therapeutic effects on AD. Both IBS and NIBS may have potential to be developed as novel treatments for AD; however, mixed findings may result from different study designs, patients selection, population, or samples sizes. Therefore, the efficacy of NIBS and IBS in AD remains uncertain, and needs to be further investigated. Moreover, more standardized study designs with larger sample sizes and longitudinal follow-up are warranted for establishing a structural guide for future studies and clinical application.
Spray nozzle investigation for the Improved Helicopter Icing Spray System (IHISS)
NASA Technical Reports Server (NTRS)
Peterson, Andrew A.; Oldenburg, John R.
1990-01-01
A contract has been awarded by the U.S. Army to design, fabricate and test a replacement for the existing Helicopter Icing Spray System. Data are shown for extensive bench and icing tunnel test programs used to select and modify an improved spray nozzle. The IHISS, capable of deployment from any CH-47 helicopter, will include new icing spray nozzles and pneumatic pressure source, and a significantly larger water tank and spray boom. The resulting system will provide a significantly larger icing cloud with droplet characteristics closely matching natural icing conditions.
Design of spur gears for improved efficiency
NASA Technical Reports Server (NTRS)
Anderson, N. E.; Loewenthal, S. H.
1981-01-01
A method to calculate spur gear system power loss for a wide range of gear geometries and operating conditions is used to determine design requirements for an efficient gearset. The effects of spur gear size, pitch, ratio, pitch-line-velocity and load on efficiency are shown. A design example is given to illustrate how the method is to be applied. In general, peak efficiencies were found to be greater for larger diameter and fine pitched gears and tare (no-load) losses were found to be significant.
The Development of a Programming Support System for Rapid Prototyping. Tasks 2 and 3.
1985-01-01
of the problems that played a role in the larger system. The principal work in Task 2 was the design of a new method for code-generation...develop- Ing a prototype of the interpreter. Due to the limitation of funds, only a design , not a prototype of the bi-directional l 2 scanner was...Introduction LiTmitUn uupii The Problem of designing a code generator for an interpreter-based languae Jas provided a chance to reoexamine fth
Guide Specification For Devices Used To Board Airline Passengers with Mobility Impairments
DOT National Transportation Integrated Search
2000-03-17
This advisory circular (AC) contains performance standards, specifications, and : recommendations for the design, construction, and testing of portable devices : used in the boarding of airline passengers with mobility impairments. Larger : aircraft ...
Carreño, Francisco; Post, Mark A
2018-01-01
Efforts in the research of tensegrity structures applied to mobile robots have recently been focused on a purely tensegrity solution to all design requirements. Locomotion systems based on tensegrity structures are currently slow and complex to control. Although wheeled locomotion provides better efficiency over distances there is no literature available on the value of wheeled methods with respect to tensegrity designs, nor on how to transition from a tensegrity structure to a fixed structure in mobile robotics. This paper is the first part of a larger study that aims to combine the flexibility, light weight, and strength of a tensegrity structure with the efficiency and simple control of a wheeled locomotion system. It focuses on comparing different types of tensegrity structure for applicability to a mobile robot, and experimentally finding an appropriate transitional region from a tensegrity structure to a conventional fixed structure on mobile robots. It applies this transitional structure to what is, to the authors' knowledge, the design of the world's first wheeled tensegrity robot that has been designed with the goal of traversing air ducts.
The space elevator: a new tool for space studies.
Edwards, Bradley C
2003-06-01
The objective has been to develop a viable scenario for the construction, deployment and operation of a space elevator using current or near future technology. This effort has been primarily a paper study with several experimental tests of specific systems. Computer simulations, engineering designs, literature studies and inclusion of existing programs have been utilized to produce a design for the first space elevator. The results from this effort illustrate a viable design using current and near-term technology for the construction of the first space elevator. The timeline for possible construction is within the coming decades and estimated costs are less than $10 B. The initial elevator would have a 5 ton/day capacity and operating costs near $100/lb for payloads going to any Earth orbit or traveling to the Moon, Mars, Venus or the asteroids. An operational space elevator would allow for larger and much longer-term biological space studies at selectable gravity levels. The high-capacity and low operational cost of this system would also allow for inexpensive searches for life throughout our solar system and the first tests of environmental engineering. This work is supported by a grant from the NASA Institute for Advanced Concepts (NIAC).
Yilmaz, Yildiz E; Bull, Shelley B
2011-11-29
Use of trait-dependent sampling designs in whole-genome association studies of sequence data can reduce total sequencing costs with modest losses of statistical efficiency. In a quantitative trait (QT) analysis of data from the Genetic Analysis Workshop 17 mini-exome for unrelated individuals in the Asian subpopulation, we investigate alternative designs that sequence only 50% of the entire cohort. In addition to a simple random sampling design, we consider extreme-phenotype designs that are of increasing interest in genetic association analysis of QTs, especially in studies concerned with the detection of rare genetic variants. We also evaluate a novel sampling design in which all individuals have a nonzero probability of being selected into the sample but in which individuals with extreme phenotypes have a proportionately larger probability. We take differential sampling of individuals with informative trait values into account by inverse probability weighting using standard survey methods which thus generalizes to the source population. In replicate 1 data, we applied the designs in association analysis of Q1 with both rare and common variants in the FLT1 gene, based on knowledge of the generating model. Using all 200 replicate data sets, we similarly analyzed Q1 and Q4 (which is known to be free of association with FLT1) to evaluate relative efficiency, type I error, and power. Simulation study results suggest that the QT-dependent selection designs generally yield greater than 50% relative efficiency compared to using the entire cohort, implying cost-effectiveness of 50% sample selection and worthwhile reduction of sequencing costs.
A comparative computational study of Csbnd N and Csbnd C bonding visible to NIR absorbing croconines
NASA Astrophysics Data System (ADS)
Chetti, Prabhakar; Tripathi, Anuj
2018-03-01
The lowest electronic excitations and charge transfer properties in two series of croconine dyes; 1) molecules with Csbnd N bonding, having an absorption in the visible region (400-600 nm) and 2) molecules with Csbnd C bonding, showing absorption in visible to near infrared (NIR) region (600-1100 nm) are analyzed by quantum-chemical calculations. The absorption maxima in Csbnd C bonding croconines (CCR) are always having 200-300 nm red shifted than its corresponding Csbnd N bonding croconines (NCR). The reason for this drastic red shift in CCR series than its corresponding NCR has been systematically studied by DFT, TDDFT and SAC-CI methods. It is found that, CCR series are with less charge transfer in nature and are having larger diradical character, whereas NCR series molecules showing larger charge transfer with lower diradical character. The change in bonding mode of central five membered croconate ring, from Csbnd N to Csbnd C, destabilization and/stabilization of HOMO LUMO levels were observed. This study may helpful in the design and synthesis of new visible to NIR absorbing croconine dyes which are useful in materials applications.
Canosa, Joel
2018-01-01
The aim of this study is the application of a software tool to the design of stripping columns to calculate the removal of trihalomethanes (THMs) from drinking water. The tool also allows calculating the rough capital cost of the column and the decrease in carcinogenic risk indeces associated with the elimination of THMs and, thus, the investment to save a human life. The design of stripping columns includes the determination, among other factors, of the height (HOG), the theoretical number of plates (NOG), and the section (S) of the columns based on the study of pressure drop. These results have been compared with THM stripping literature values, showing that simulation is sufficiently conservative. Three case studies were chosen to apply the developed software. The first case study was representative of small-scale application to a community in Córdoba (Spain) where chloroform is predominant and has a low concentration. The second case study was of an intermediate scale in a region in Venezuela, and the third case study was representative of large-scale treatment of water in the Barcelona metropolitan region (Spain). Results showed that case studies with larger scale and higher initial risk offer the best capital investment to decrease the risk. PMID:29562670
Non-neural BOLD variability in block and event-related paradigms.
Kannurpatti, Sridhar S; Motes, Michael A; Rypma, Bart; Biswal, Bharat B
2011-01-01
Block and event-related stimulus designs are typically used in fMRI studies depending on the importance of detection power or estimation efficiency. The extent of vascular contribution to variability in block and event-related fMRI-BOLD response is not known. With scaling, the extent of vascular variability in the fMRI-BOLD response during block and event-related design tasks was investigated. Blood oxygen level-dependent (BOLD) contrast data from healthy volunteers performing a block design motor task and an event-related memory task requiring performance of a motor response were analyzed from the regions of interest (ROIs) surrounding the primary and supplementary motor cortices. Average BOLD signal change was significantly larger during the block design compared to the event-related design. In each subject, BOLD signal change across voxels in the ROIs had higher variation during the block design task compared to the event-related design task. Scaling using the resting state fluctuation of amplitude (RSFA) and breath-hold (BH), which minimizes BOLD variation due to vascular origins, reduced the within-subject BOLD variability in every subject during both tasks but significantly reduced BOLD variability across subjects only during the block design task. The strong non-neural source of intra- and intersubject variability of BOLD response during the block design compared to event-related task indicates that study designs optimizing for statistical power through enhancement of the BOLD contrast (for, e.g., block design) can be affected by enhancement of non-neural sources of BOLD variability. Copyright © 2011. Published by Elsevier Inc.
Kuiper Belt Object Orbiter Using Advanced Radioisotope Power Sources and Electric Propulsion
NASA Technical Reports Server (NTRS)
Oleson, Steven R.; McGuire, Melissa L.; Dankanich, John; Colozza, Anthony; Schmitz, Paul; Khan, Omair; Drexler, Jon; Fittje, James
2011-01-01
A joint NASA GRC/JPL design study was performed for the NASA Radioisotope Power Systems Office to explore the use of radioisotope electric propulsion for flagship class missions. The Kuiper Belt Object Orbiter is a flagship class mission concept projected for launch in the 2030 timeframe. Due to the large size of a flagship class science mission larger radioisotope power system building blocks were conceptualized to provide the roughly 4 kW of power needed by the NEXT ion propulsion system and the spacecraft. Using REP the spacecraft is able to rendezvous with and orbit a Kuiper Belt object in 16 years using either eleven (no spare) 420 W advanced RTGs or nine (with a spare) 550 W advanced Stirling Radioisotope systems. The design study evaluated integrating either system and estimated impacts on cost as well as required General Purpose Heat Source requirements.
Barhoum, Erek; Johnston, Richard; Seibel, Eric
2005-09-19
An optical model of an ultrathin scanning fiber endoscope was constructed using a non-sequential ray tracing program and used to study the relationship between fiber deflection and collection efficiency from tissue. The problem of low collection efficiency of confocal detection through the scanned single-mode optical fiber was compared to non-confocal cladding detection. Collection efficiency is 40x greater in the non-confocal versus the confocal geometry due to the majority of rays incident on the core being outside the numerical aperture. Across scan angles of 0 to 30o, collection efficiency decreases from 14.4% to 6.3% for the non-confocal design compared to 0.34% to 0.10% for the confocal design. Non-confocality provides higher and more uniform collection efficiencies at larger scan angles while sacrificing the confocal spatial filter.
1982-05-01
larger aircraft. The new winglet design, which for the Lear jet Longhorn is not really a new design at all, but a new application for it. Several...there is room because of the cost constraint, those that want can also blend into this degree a maintenance management degree that includes an A and P
Evaluating Social Programs at the State and Local Level. The JTPA Evaluation Design Project.
ERIC Educational Resources Information Center
Blalock, Ann Bonar, Ed.; And Others
This book on evaluating social programs is an outcome of the Job Training Partnership Act (JTPA) Evaluation Design Project, which produced a set of 10 guides for the evaluation of state and local JTPA programs. This book distills ideas from these guides and applies them to a larger context. Part 1 presents a general approach to program evaluation…
NASA Technical Reports Server (NTRS)
Fink, R. A.; Ellis, R. C.
1996-01-01
The trend toward smaller satellites has challenged component manufacturers to reduce the size, weight, and cost of their products while maintaining high performance. Both a new stepper motor and a new harmonic drive were developed to meet this need. The resulting actuator embodies small angle stepper technology usually reserved for larger units and incorporates an integral approach to harmonic drive design. By product simplifications, costs were significantly reduced over prior designs.
Effects of Vocabulary Size on Online Lexical Processing by Preschoolers.
Law, Franzo; Edwards, Jan R
This study was designed to investigate the relationship between vocabulary size and the speed and accuracy of lexical processing in preschoolers between the ages of 30-46 months using an automatic eye tracking task based on the looking-while-listening paradigm (Fernald, Zangl, Portillo, & Marchman, 2008) and mispronunciation paradigm (White & Morgan, 2008). Children's eye gaze patterns were tracked while they looked at two pictures (one familiar object, one unfamiliar object) on a computer screen and simultaneously heard one of three kinds of auditory stimuli: correct pronunciations of the familiar object's name, one-feature mispronunciations of the familiar object's name, or a nonword. The results showed that children with larger expressive vocabularies, relative to children with smaller expressive vocabularies, were more likely to look to a familiar object upon hearing a correct pronunciation and to an unfamiliar object upon hearing a novel word. Results also showed that children with larger expressive vocabularies were more sensitive to mispronunciations; they were more likely to look toward the unfamiliar object rather than the familiar object upon hearing a one-feature mispronunciation of a familiar object-name. These results suggest that children with smaller vocabularies, relative to their larger-vocabulary age peers, are at a disadvantage for learning new words, as well as for processing familiar words.
Perceived Spaciousness and Preference in Sequential Experience.
Bokharaei, Saleheh; Nasar, Jack L
2016-11-01
We assessed the perceived spaciousness and preference for a destination space in relation to six attributes (size, lighting, window size, texture, wall mural, and amount of furniture) of it and of the space experienced before it. Studies have examined effects of these attributes but not for dynamic experience or preference. We created 24 virtual reality walks between each possible pair of two levels of each attribute. For each destination space, 31 students (13 men, 18 women) rated spaciousness and 30 students (16 men, 14 women) rated preference. We conducted separate 2 × 2 repeated-measure ANOVAs across each condition for perceived spaciousness and preference. Participants judged the space that was larger, was more brightly lit, with a larger window, or with less furniture as the more spacious. These attributes also increased preference. Consonant with adaptation-level theory, participants judged offices as higher in spaciousness and preference if preceded by a space that was smaller, was more dimly lit, or had smaller windows. The findings suggest that perceived spaciousness varies with size, lightness, window size, and amount of furniture but that perception also depends on the size, lightness, and size of the space experienced before. Designers could use the findings to manipulate features to make a space appear larger or more desirable. © 2016, Human Factors and Ergonomics Society.
Espinoza, Mario; Lédée, Elodie J I; Simpfendorfer, Colin A; Tobin, Andrew J; Heupel, Michelle R
2015-12-01
Understanding the efficacy of marine protected areas (MPAs) for wide-ranging predators is essential to designing effective management and conservation approaches. The use of acoustic monitoring and network analysis can improve our understanding of the spatial ecology and functional connectivity of reef-associated species, providing a useful approach for reef-based conservation planning. This study compared and contrasted the movement and connectivity of sharks with different degrees of reef association. We examined the residency, dispersal, degree of reef connectivity, and MPA use of grey reef (Carcharhinus amblyrhynchos), silvertip (C. albimarginatus), and bull (C. leucas) sharks monitored in the central Great Barrier Reef (GBR). An array of 56 acoustic receivers was used to monitor shark movements on 17 semi-isolated reefs. Carcharhinus amblyrhynchos and C. albimarginatus were detected most days at or near their tagging reef. However, while C. amblyrhynchos spent 80% of monitoring days in the array, C. albimarginatus was only detected 50% of the time. Despite both species moving similar distances (< 50 km), a large portion of the population of C. albimarginatus (71%) was detected on multiple reefs and moved more frequently between reefs and management zones than C. amblyrhynchos. Carcharhinus leucas was detected less than 20% of the time within the tagging array, and 42% of the population undertook long-range migrations to other arrays in the GBR. Networks derived for C. leucas were larger and more complex than those for C. amblyrhynchos and C. albimarginatus. Our findings suggest that protecting specific reefs based on prior knowledge (e.g., healthier reefs with high fish biomass) and increasing the level of protection to include nearby, closely spaced reef habitats (< 20 km) may perform better for species like C. albimarginatus than having either a single or a network of isolated MPAs. This design would also provide protection for larger male C. amblyrhynchos, which tend to disperse more and use larger areas than females. For wide-ranging sharks like C. leucas, a combination of spatial planning and other alternative measures is critical. Our findings demonstrate that acoustic monitoring can serve as a useful platform for designing more effective MPA networks for reef predators displaying a range of movement patterns.
Tools for Designing and Analyzing Structures
NASA Technical Reports Server (NTRS)
Luz, Paul L.
2005-01-01
Structural Design and Analysis Toolset is a collection of approximately 26 Microsoft Excel spreadsheet programs, each of which performs calculations within a different subdiscipline of structural design and analysis. These programs present input and output data in user-friendly, menu-driven formats. Although these programs cannot solve complex cases like those treated by larger finite element codes, these programs do yield quick solutions to numerous common problems more rapidly than the finite element codes, thereby making it possible to quickly perform multiple preliminary analyses - e.g., to establish approximate limits prior to detailed analyses by the larger finite element codes. These programs perform different types of calculations, as follows: 1. determination of geometric properties for a variety of standard structural components; 2. analysis of static, vibrational, and thermal- gradient loads and deflections in certain structures (mostly beams and, in the case of thermal-gradients, mirrors); 3. kinetic energies of fans; 4. detailed analysis of stress and buckling in beams, plates, columns, and a variety of shell structures; and 5. temperature dependent properties of materials, including figures of merit that characterize strength, stiffness, and deformation response to thermal gradients
NASA Technical Reports Server (NTRS)
Roozeboom, Nettie H.; Lee, Henry C.; Simurda, Laura J.; Zilliac, Gregory G.; Pulliam, Thomas H.
2016-01-01
Wing-body juncture flow fields on commercial aircraft configurations are challenging to compute accurately. The NASA Advanced Air Vehicle Program's juncture flow committee is designing an experiment to provide data to improve Computational Fluid Dynamics (CFD) modeling in the juncture flow region. Preliminary design of the model was done using CFD, yet CFD tends to over-predict the separation in the juncture flow region. Risk reduction wind tunnel tests were requisitioned by the committee to obtain a better understanding of the flow characteristics of the designed models. NASA Ames Research Center's Fluid Mechanics Lab performed one of the risk reduction tests. The results of one case, accompanied by CFD simulations, are presented in this paper. Experimental results suggest the wall mounted wind tunnel model produces a thicker boundary layer on the fuselage than the CFD predictions, resulting in a larger wing horseshoe vortex suppressing the side of body separation in the juncture flow region. Compared to experimental results, CFD predicts a thinner boundary layer on the fuselage generates a weaker wing horseshoe vortex resulting in a larger side of body separation.
A Broadband Bessel Beam Launcher Using Metamaterial Lens
Qing Qi, Mei; Tang, Wen Xuan; Cui, Tie Jun
2015-01-01
An approach of generating broadband Bessel beams is presented. The broadband Bessel beams are produced by a gradient index (GRIN) metamaterial lens illuminated by broadband waveguide antenna. The metamaterial lens is constructed with multi-layered structure and each layer is composed of GRIN metamaterials. The metamaterials are designed as dielectric plates printed with metallic patterns in the center region and drilled by air holes near the edge, which operate in wide band. The metamaterial lens serves as a convertor which transforms the spherical beams emitted from feed into conical beams. The conical beams form quasi-Bessel beams in the near-field region. The aperture diameter of the GRIN lens is much larger than the operating wavelength to guarantee the transformation. In principle, this kind of metamaterial lens can produce Bessel beams at arbitrary distance by designing the refractive-index distribution. To verify the approach, we have designed, fabricated and tested a metamaterial lens. Full-wave simulation and experiment results have proved that the generated Bessel beams can be maintained in distance larger than 1 meter within a ranging from 12 GHz to 18 GHz. PMID:26122861
A Broadband Bessel Beam Launcher Using Metamaterial Lens.
Qi, Mei Qing; Tang, Wen Xuan; Cui, Tie Jun
2015-06-30
An approach of generating broadband Bessel beams is presented. The broadband Bessel beams are produced by a gradient index (GRIN) metamaterial lens illuminated by broadband waveguide antenna. The metamaterial lens is constructed with multi-layered structure and each layer is composed of GRIN metamaterials. The metamaterials are designed as dielectric plates printed with metallic patterns in the center region and drilled by air holes near the edge, which operate in wide band. The metamaterial lens serves as a convertor which transforms the spherical beams emitted from feed into conical beams. The conical beams form quasi-Bessel beams in the near-field region. The aperture diameter of the GRIN lens is much larger than the operating wavelength to guarantee the transformation. In principle, this kind of metamaterial lens can produce Bessel beams at arbitrary distance by designing the refractive-index distribution. To verify the approach, we have designed, fabricated and tested a metamaterial lens. Full-wave simulation and experiment results have proved that the generated Bessel beams can be maintained in distance larger than 1 meter within a ranging from 12 GHz to 18 GHz.
NASA Technical Reports Server (NTRS)
Green, Rebecca
2017-01-01
Solid rockets are of interest to the space program because they are commonly used as boosters that provide the additional thrust needed for the space launch vehicle to escape the gravitational pull of the Earth. Larger, more advanced solid rockets allow for space launch vehicles with larger payload capacities, enabling mankind to reach new depths of space. This presentation will discuss, in detail, the history of solid rockets. The history begins with the invention and origin of the solid rocket, and then goes into the early uses and design of the solid rocket. The evolution of solid rockets is depicted by a description of how solid rockets changed and improved and how they were used throughout the 16th, 17th, 18th, and 19th centuries. Modern uses of the solid rocket include the Solid Rocket Boosters (SRBs) on the Space Shuttle and the solid rockets used on current space launch vehicles. The functions and design of the SRB and the advancements in solid rocket technology since the use of the SRB are discussed as well. Common failure modes and design difficulties are discussed as well.
Sustaining GHz oscillation of carbon nanotube based oscillators via a MHz frequency excitation
NASA Astrophysics Data System (ADS)
Motevalli, Benyamin; Taherifar, Neda; Zhe Liu, Jefferson
2016-05-01
There have been intensive studies to investigate the properties of gigahertz nano-oscillators based on multi-walled carbon nanotubes (MWCNTs). Many of these studies, however, revealed that the unique telescopic translational oscillations in such devices would damp quickly due to various energy dissipation mechanisms. This challenge remains the primary obstacle against its practical applications. Herein, we propose a design concept in which a GHz oscillation could be re-excited by a MHz mechanical motion. This design involves a triple-walled CNT, in which sliding of the longer inner tube at a MHz frequency can re-excite and sustain a GHz oscillation of the shorter middle tube. Our molecular dynamics (MD) simulations prove this design concept at ˜10 nm scale. A mathematical model is developed to explore the feasibility at a larger size scale. As an example, in an oscillatory system with the CNT’s length above 100 nm, the high oscillatory frequency range of 1.8-3.3 GHz could be excited by moving the inner tube at a much lower frequency of 53.4 MHz. This design concept together with the mechanical model could energize the development of GHz nano-oscillators in miniaturized electro-mechanical devices.
NASA Astrophysics Data System (ADS)
Peltoniemi, Jouni I.; Hakala, Teemu; Suomalainen, Juha; Honkavaara, Eija; Markelin, Lauri; Gritsevich, Maria; Eskelinen, Juho; Jaanson, Priit; Ikonen, Erkki
2014-10-01
The measurement uncertainty and traceability of the Finnish Geodetic Institutess field gonio-spectro-polarimeter FIGIFIGO have been assessed. First, the reference standard (Spectralon sample) was measured at the National Standard Laboratory of MIKES-Aalto. This standard was transferred to FGIs field reference standard (larger Spectralon sample), and from that to the unmanned aerial vehicle (UAV), reference standards (1 m2 plates). The reflectance measurement uncertainty of FIGIFIGO has been estimated to be 0.01 in ideal laboratory conditions, but about 0.02-0.05 in typical field conditions, larger at larger solar or observation zenith angles. Target specific uncertainties can increase total uncertainty even to 0.1-0.2. The angular reading uncertainty is between 1° and 3°, depending on user selection, and the polarisation uncertainty is around 0.01. For UAV, the transferred reflectance uncertainty is about 0.05-0.1, depending on, how ideal the measurement conditions are. The design concept of FIGIFIGO has been proved to have a number of advantages, such as a well-adopted user-friendly interface, a high level of automation and excellent suitability for the field measurements. It is a perfect instrument for collection of reference data on a given target in natural (and well-recorded) conditions. In addition to the strong points of FIGIFIGO, the current study reveals several issues that need further attention, such as the field of view, illumination quality, polarisation calibration, Spectralon reflectance and polarisation properties in the 1000-2400 nm range.
Design and logistics of integrated spacecraft/lander lunar habitat concepts
NASA Technical Reports Server (NTRS)
Hypes, Warren D.; Wright, Robert L.; Gould, Marston J.; Lovelace, U. M.
1991-01-01
Integrated spacecraft/lander combinations have been designed to provide a support structure for thermal and galactic radiation shielding for three initial lunar habitat concepts. Integrating the support structure with the habitat reduces the logistics requirements for the implantation of the initial base. The designs are simple, make use of existing technologies, and minimize the amount of lunar surface preparation and crew activity. The design facilitates continued use of all elements in the development of a permanent lunar base and precludes the need for an entirely different structure of larger volume and increased complexity of implantation. This design philosophy, coupled with the reduced logistics, increases overall cost effectiveness.
IDEAS: A multidisciplinary computer-aided conceptual design system for spacecraft
NASA Technical Reports Server (NTRS)
Ferebee, M. J., Jr.
1984-01-01
During the conceptual development of advanced aerospace vehicles, many compromises must be considered to balance economy and performance of the total system. Subsystem tradeoffs may need to be made in order to satisfy system-sensitive attributes. Due to the increasingly complex nature of aerospace systems, these trade studies have become more difficult and time-consuming to complete and involve interactions of ever-larger numbers of subsystems, components, and performance parameters. The current advances of computer-aided synthesis, modeling and analysis techniques have greatly helped in the evaluation of competing design concepts. Langley Research Center's Space Systems Division is currently engaged in trade studies for a variety of systems which include advanced ground-launched space transportation systems, space-based orbital transfer vehicles, large space antenna concepts and space stations. The need for engineering analysis tools to aid in the rapid synthesis and evaluation of spacecraft has led to the development of the Interactive Design and Evaluation of Advanced Spacecraft (IDEAS) computer-aided design system. The ADEAS system has been used to perform trade studies of competing technologies and requirements in order to pinpoint possible beneficial areas for research and development. IDEAS is presented as a multidisciplinary tool for the analysis of advanced space systems. Capabilities range from model generation and structural and thermal analysis to subsystem synthesis and performance analysis.
Guo, Yin; Sun, LiQun; Yang, Zheng; Liu, Zilong
2016-02-20
During this study we constructed a generalized parametric modified four-objective multipass matrix system (MMS). We used an optical system comprising four asymmetrical spherical mirrors to improve the alignment process. The use of a paraxial equation for the design of the front transfer optics yielded the initial condition for modeling our MMS. We performed a ray tracing simulation to calculate the significant aberration of the system (astigmatism). Based on the calculated meridional and sagittal focus positions, the complementary focusing mirror was easily designed to provide an output beam free of astigmatism. We have presented an example of a 108-transit multipass system (5×7 matrix arrangement) with a relatively larger numerical aperture source (xenon light source). The whole system exhibits zero theoretical geometrical loss when simulated with Zemax software. The MMS construction strategy described in this study provides an anastigmatic output beam and the generalized approach to design a controllable matrix spot pattern on the field mirrors. Asymmetrical reflective mirrors aid in aligning the whole system with high efficiency. With the generalized design strategy in terms of optics configuration and asymmetrical fabrication method in this paper, other kinds of multipass matrix system coupled with different sources and detector systems also can be achieved.
Mindfulness-based interventions with youth: A comprehensive meta-analysis of group-design studies.
Klingbeil, David A; Renshaw, Tyler L; Willenbrink, Jessica B; Copek, Rebecca A; Chan, Kai Tai; Haddock, Aaron; Yassine, Jordan; Clifton, Jesse
2017-08-01
The treatment effects of Mindfulness-Based Interventions (MBIs) with youth were synthesized from 76 studies involving 6121 participants. A total of 885 effect sizes were aggregated using meta-regression with robust variance estimation. Overall, MBIs were associated with small treatment effects in studies using pre-post (g=0.305, SE=0.039) and controlled designs (g=0.322, SE=0.040). Treatment effects were measured after a follow-up period in 24 studies (n=1963). Results demonstrated that treatment effects were larger at follow-up than post-treatment in pre-post (g=0.462, SE=0.118) and controlled designs (g=0.402, SE=0.081). Moderator analyses indicated that intervention setting and intervention dosage were not meaningfully related to outcomes after controlling for study design quality. With that said, the between-study heterogeneity in the intercept-only models was consistently small, thus limiting the amount of variance for the moderators to explain. A series of exploratory analyses were used to investigate the differential effectiveness of MBIs across four therapeutic process domains and seven therapeutic outcome domains. Small, positive results were generally observed across the process and outcome domains. Notably, MBIs were associated with moderate effects on the process variable of mindfulness in controlled studies (n=1108, g=0.510). Limitations and directions for future research and practice are discussed. Copyright © 2017 Society for the Study of School Psychology. Published by Elsevier Ltd. All rights reserved.
Al-Fahdawi, Mahmood Abd; El-Kassaby, Marwa Abdelwahab; Farid, Mary Medhat; El-Fotouh, Mona Abou
2018-01-01
Objective The objective of this study was to assess the volume, area, and dimensions of the oropharyngeal airway (OPA) in a previously repaired nonsyndromic unilateral cleft lip and palate (UCLP) versus bilateral cleft lip and palate (BCLP) patients when compared with noncleft controls using cone beam computed tomography (CBCT). Design This was a retrospective case-control study. Setting The Cleft Care Center and outpatient clinic that are affiliated to our faculty were the settings for the study. Participants A total of 58 CBCT scans were selected of preadolescent individuals: 14 BCLP, 20 UCLP, and 24 age- and gender-matched noncleft controls. Variables Variables were volume, cross-sectional area (CSA), midsagittal area (MSA), and dimensions of OPA. Statistical analysis One-way analysis of variance and post hoc tests were used to compare variables. Statistical significance was set at P ≤ .05. Results UCLP showed significantly smaller superior oropharyngeal airway volume than both controls and BCLP ( P ≤ .05). BCLP showed significantly larger CSA at soft palate plane and significantly larger MSA than both UCLP and controls ( P < .05). Conclusions UCLP patients at the studied age and stage of previously repaired clefts have significantly less superior oropharyngeal airway volume than both controls and BCLP patients. This confirms that preadolescents with UCLP are at greater risk for superior oropharyngeal airway obstruction when compared with those BCLP and controls. Furthermore, BCLP patients showed significantly larger CSA at soft palate plane and MSA than both controls and UCLP patients. These variations in OPA characteristics of cleft patients can influence function in terms of respiration and vocalization.
Broom, Margaret; Kecskes, Zsuzsoka; Kildea, Sue; Gardner, Anne
2018-01-01
In 2012, a tertiary neonatal intensive care unit (NICU) transitioned from an open plan (OP) to a dual occupancy (DO) NICU. The DO design aimed to provide a developmental appropriate, family-centered environment for neonates and their families. During planning, staff questioned the impact DO would have on staff workflow and activity. To explore the impact of changing from an OP to a DO NICU, a prospective longitudinal study was undertaken from 2011 to 2014, using observational, time and motion, and surveys methods. Main outcome measures included distance walked by staff, minutes of staff activity, and staff perceptions of the DO design. Results highlighted no significant difference in the distances clinical nurses walked nor time spent providing direct clinical care, whereas technical support staff walked further than other staff in both designs. Staff perceived the DO design created a developmentally appropriate, family-centered environment that facilitated communication and collaboration between staff and families. Staff described the main challenges of the DO design such as effective staff communication, gaining educational opportunities, and the isolation of staff and families compared to the OP design. Our study provides new evidence that DO provides an improved developmentally environment and has similar positive benefits to single-family room for neonates and families. Such design may reduce the larger floor plan's impact on staff walking distance and work practices. Challenges of staff transition can be minimized by planning and leadership throughout the development and move to a new design.
BMP UNIT PROCESS DESIGN, MONITORING, AND PERFORMANCE
Urbanization results in more impervious areas that cause larger quantities of stormwater runoff. This runoff can contribute significant amounts of pollutants (e.g., litter, oils, microorganisms, sediments, nutrients, organic matter, and heavy metals) to receiving waters. To impro...
42 CFR 5a.3 - Definition of Underserved Rural Community.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 3 that are larger than 400 square miles and have population density of less than 30 people per square mile; and (b) Located in a current: (1) Federally-designated Primary Health Care Geographic Health...
Covering the Plane with Rep-Tiles.
ERIC Educational Resources Information Center
Fosnaugh, Linda S.; Harrell, Marvin E.
1996-01-01
Presents an activity in which students use geometric figures, rep-tiles, to design a tile floor. Rep-tiles are geometric figures of which copies can fit together to form a larger similar figure. Includes reproducible student worksheet. (MKR)