Maximizing research study effectiveness in malaria elimination settings: a mixed methods study to capture the experiences of field-based staff.

PubMed

Canavati, Sara E; Quintero, Cesia E; Haller, Britt; Lek, Dysoley; Yok, Sovann; Richards, Jack S; Whittaker, Maxine Anne

2017-09-11

In a drug-resistant, malaria elimination setting like Western Cambodia, field research is essential for the development of novel anti-malarial regimens and the public health solutions necessary to monitor the spread of resistance and eliminate infection. Such field studies often face a variety of similar implementation challenges, but these are rarely captured in a systematic way or used to optimize future study designs that might overcome similar challenges. Field-based research staff often have extensive experience and can provide valuable insight regarding these issues, but their perspectives and experiences are rarely documented and seldom integrated into future research protocols. This mixed-methods analysis sought to gain an understanding of the daily challenges encountered by research field staff in the artemisinin-resistant, malaria elimination setting of Western Cambodia. In doing so, this study seeks to understand how the experiences and opinions of field staff can be captured, and used to inform future study designs. Twenty-two reports from six field-based malaria studies conducted in Western Cambodia were reviewed using content analysis to identify challenges to conducting the research. Informal Interviews, Focus Group Discussions and In-depth Interviews were also conducted among field research staff. Thematic analysis of the data was undertaken using Nvivo 9 ® software. Triangulation and critical case analysis was also used. There was a lack of formalized avenues through which field workers could report challenges experienced when conducting the malaria studies. Field research staff faced significant logistical barriers to participant recruitment and data collection, including a lack of available transportation to cover long distances, and the fact that mobile and migrant populations (MMPs) are usually excluded from studies because of challenges in follow-up. Cultural barriers to communication also hindered participant recruitment and created unexpected delays. Field staff often paid a physical, emotional and financial cost, going beyond their duty in order to keep the study running. Formal monthly reports filled out by field study staff could be a key tool for capturing field study staff experiences effectively, but require specific report fields to encourage staff to outline their challenges and to propose potential solutions. Forging strong bonds with communities and their leaders may improve communication, and decrease barriers to participant recruitment. Study designs that make it feasible for MMPs to participate should be pursued; in addition to increasing the potential participant pool, this will ensure that the most malaria-endemic demographic is taken into account in research studies. Overlaps between clinical care and research create ethical dilemmas for study staff, a fact that warrants careful consideration. Lessons learned from study field staff should be used to create a set of locally-relevant recommendations to inform future study designs.

Clinical Trial Design in Neuroendocrine Tumors.

PubMed

Halperin, Daniel M; Yao, James C

2016-02-01

Neuroendocrine tumors (NETs) present tremendous opportunities for productive clinical investigation, but substantial challenges as well. Investigators must be aware of common pitfalls in study design, informed by an understanding of the history of trials in the field, to make the best use of available data and our patient volunteers. We believe the salient issues in clinical trial design and interpretation in the NET field are patient homogeneity, standardized response assessment, and rigorous design and execution. Whether designing or interpreting a study in patients with NET, these principles should drive assessment. Copyright © 2016 Elsevier Inc. All rights reserved.

Design elements in implementation research: a structured review of child welfare and child mental health studies.

PubMed

Landsverk, John; Brown, C Hendricks; Rolls Reutz, Jennifer; Palinkas, Lawrence; Horwitz, Sarah McCue

2011-01-01

Implementation science is an emerging field of research with considerable penetration in physical medicine and less in the fields of mental health and social services. There remains a lack of consensus on methodological approaches to the study of implementation processes and tests of implementation strategies. This paper addresses the need for methods development through a structured review that describes design elements in nine studies testing implementation strategies for evidence-based interventions addressing mental health problems of children in child welfare and child mental health settings. Randomized trial designs were dominant with considerable use of mixed method designs in the nine studies published since 2005. The findings are discussed in reference to the limitations of randomized designs in implementation science and the potential for use of alternative designs.

Material and cooling requirements for poly-Bitter resistive magnets and hybrid inserts generating continuous fields up to 50 T

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gao, B.J.; Bird, M.D.; Eyssa, Y.M.

1994-07-01

The new National High Magnetic Field Laboratory (NHMFL), equipped with a 40 MW DC power supply, will design and construct the next generation of high field resistive magnets and hybrid inserts generating DC fields up to 50 T. The authors present a study on the required materials and the necessary cooling characteristics, these magnets need. The configuration selected for this study consists of a combination of thin poly-Bitter and thick Bitter coils optimized in dimensions and power under constraint of maximum design stress and heat removal to obtain maximum field. The study shows that each design requires a different optimummore » ratio of conductor strength to electrical conductivity and that efficient cooling is only advantageous if strong copper alloys are used. For efficient use of the available power the development of new high strength, high conductivity materials will be necessary. Equally important are improvements in the heat transfer characteristics of these high power density magnets.« less

Design and commissioning of a high magnetic field muon spin relaxation spectrometer at the ISIS pulsed neutron and muon source

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lord, J. S.; McKenzie, I.; Baker, P. J.

2011-07-15

The high magnetic field (HiFi) muon instrument at the ISIS pulsed neutron and muon source is a state-of-the-art spectrometer designed to provide applied magnetic fields up to 5 T for muon studies of condensed matter and molecular systems. The spectrometer is optimised for time-differential muon spin relaxation studies at a pulsed muon source. We describe the challenges involved in its design and construction, detailing, in particular, the magnet and detector performance. Commissioning experiments have been conducted and the results are presented to demonstrate the scientific capabilities of the new instrument.

New quality assurance program integrating "modern radiotherapy" within the German Hodgkin Study Group.

PubMed

Kriz, J; Baues, C; Engenhart-Cabillic, R; Haverkamp, U; Herfarth, K; Lukas, P; Schmidberger, H; Marnitz-Schulze, S; Fuchs, M; Engert, A; Eich, H T

2017-02-01

Field design changed substantially from extended-field RT (EF-RT) to involved-field RT (IF-RT) and now to involved-node RT (IN-RT) and involved-site RT (IS-RT) as well as treatment techniques in radiotherapy (RT) of Hodgkin's lymphoma (HL). The purpose of this article is to demonstrate the establishment of a quality assurance program (QAP) including modern RT techniques and field designs within the German Hodgkin Study Group (GHSG). In the era of modern conformal RT, this QAP had to be fundamentally adapted and a new evaluation process has been intensively discussed by the radiotherapeutic expert panel of the GHSG. The expert panel developed guidelines and criteria to analyse "modern" field designs and treatment techniques. This work is based on a dataset of 11 patients treated within the sixth study generation (HD16-17). To develop a QAP of "modern RT", the expert panel defined criteria for analysing current RT procedures. The consensus of a modified QAP in ongoing and future trials is presented. With this schedule, the QAP of the GHSG could serve as a model for other study groups.

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.

Performance of Subsurface Tube Drainage System in Saline Soils: A Case Study

NASA Astrophysics Data System (ADS)

Pali, A. K.

2015-06-01

In order to improve the saline and water logged soils caused due to groundwater table rise, installation of subsurface drainage system is considered as one of the best remedies. However, the design of the drainage system has to be accurate so that the field performance results conform to the designed results. In this investigation, the field performance of subsurface tube drainage system installed at the study area was evaluated. The performance was evaluated on the basis of comparison of the designed value of water table drop as 30 cm after 2 days of drainage and predicted and field measured hydraulic heads for a consecutive drainage period of 14 days. The investigation revealed that the actual drop of water table after 2 days of drainage was 25 cm, about 17 % less than the designed value of 30 cm after 2 days of drainage. The comparison of hydraulic heads predicted by Van Schilfgaarde equation of unsteady drainage with the field-measured hydraulic heads showed that the deviation of predicted hydraulic heads varied within a range of ±8 % indicating high acceptability of Van Schlifgaarde equation for designing subsurface drainage system in saline and water logged soils resembling to that of the study area.

Corn blight review: Sampling model and ground data measurements program

NASA Technical Reports Server (NTRS)

Allen, R. D.

1972-01-01

The sampling plan involved the selection of the study area, determination of the flightline and segment sample design within the study area, and determination of a field sample design. Initial interview survey data consisting of crop species acreage and land use were collected. On all corn fields, additional information such as seed type, row direction, population, planting date, ect. were also collected. From this information, sample corn fields were selected to be observed through the growing season on a biweekly basis by county extension personnel.

Magnetic design and field optimization of a superferric dipole for the RISP fragment separator

NASA Astrophysics Data System (ADS)

Zaghloul, A.; Kim, J. Y.; Kim, D. G.; Jo, H. C.; Kim, M. J.

2015-10-01

The in-flight fragment separator of the Rare Isotope Science Project requires eight dipole magnets to produce a gap field of 1.7 T in a deflection sector of 30 degree with a 6-m central radius. If the beam-optics requirements are to be met, an integral field homogeneity of a few units (1 unit = 10-4) must be achieved. A superferric dipole magnet has been designed by using the Low-Temperature Superconducting wire NbTi and soft iron of grade SAE1010. The 3D magnetic design and field optimization have been performed using the Opera code. The length and the width of the air slots in the poles have been determined in an optimization process that considered not only the uniformity of the field in the straight section but also the field errors in the end regions. The field uniformity has also been studied for a range of operation of the dipole magnet from 0.4 T to 1.7 T. The magnetic design and field uniformity are discussed.

Designs of Empirical Evaluations of Nonexperimental Methods in Field Settings.

PubMed

Wong, Vivian C; Steiner, Peter M

2018-01-01

Over the last three decades, a research design has emerged to evaluate the performance of nonexperimental (NE) designs and design features in field settings. It is called the within-study comparison (WSC) approach or the design replication study. In the traditional WSC design, treatment effects from a randomized experiment are compared to those produced by an NE approach that shares the same target population. The nonexperiment may be a quasi-experimental design, such as a regression-discontinuity or an interrupted time-series design, or an observational study approach that includes matching methods, standard regression adjustments, and difference-in-differences methods. The goals of the WSC are to determine whether the nonexperiment can replicate results from a randomized experiment (which provides the causal benchmark estimate), and the contexts and conditions under which these methods work in practice. This article presents a coherent theory of the design and implementation of WSCs for evaluating NE methods. It introduces and identifies the multiple purposes of WSCs, required design components, common threats to validity, design variants, and causal estimands of interest in WSCs. It highlights two general approaches for empirical evaluations of methods in field settings, WSC designs with independent and dependent benchmark and NE arms. This article highlights advantages and disadvantages for each approach, and conditions and contexts under which each approach is optimal for addressing methodological questions.

FACTORS INFLUENCING THE DESIGN OF BIOACCUMULATION FACTOR AND BIOTA-SEDIMENT ACCUMULATION FACTOR FIELD STUDIES

EPA Science Inventory

A series of modeling simulations were performed to develop an understanding of the underlying factors and principles involved in developing field sampling designs for measuring bioaccumulation factors (BAFs) and biota-sediment accumulation factors (BSAFs. These simulations reveal...

A Handheld Open-Field Infant Keratometer (An American Ophthalmological Society Thesis)

PubMed Central

Miller, Joseph M.

2010-01-01

Purpose: To design and evaluate a new infant keratometer that incorporates an unobstructed view of the infant with both eyes (open-field design). Methods: The design of the open-field infant keratometer is presented, and details of its construction are given. The design incorporates a single-ring keratoscope for measurement of corneal astigmatism over a 4-mm region of the cornea and includes a rectangular grid target concentric within the ring to allow for the study of higher-order aberrations of the eye. In order to calibrate the lens and imaging system, a novel telecentric test object was constructed and used. The system was bench calibrated against steel ball bearings of known dimensions and evaluated for accuracy while being used in handheld mode in a group of 16 adult cooperative subjects. It was then evaluated for testability in a group of 10 infants and toddlers. Results: Results indicate that while the device achieved the goal of creating an open-field instrument containing a single-ring keratoscope with a concentric grid array for the study of higher-order aberrations, additional work is required to establish better control of the vertex distance. Conclusion: The handheld open-field infant keratometer demonstrates testability suitable for the study of infant corneal astigmatism. Use of collimated light sources in future iterations of the design must be incorporated in order to achieve the accuracy required for clinical investigation. PMID:21212850

A handheld open-field infant keratometer (an american ophthalmological society thesis).

PubMed

Miller, Joseph M

2010-12-01

To design and evaluate a new infant keratometer that incorporates an unobstructed view of the infant with both eyes (open-field design). The design of the open-field infant keratometer is presented, and details of its construction are given. The design incorporates a single-ring keratoscope for measurement of corneal astigmatism over a 4-mm region of the cornea and includes a rectangular grid target concentric within the ring to allow for the study of higher-order aberrations of the eye. In order to calibrate the lens and imaging system, a novel telecentric test object was constructed and used. The system was bench calibrated against steel ball bearings of known dimensions and evaluated for accuracy while being used in handheld mode in a group of 16 adult cooperative subjects. It was then evaluated for testability in a group of 10 infants and toddlers. Results indicate that while the device achieved the goal of creating an open-field instrument containing a single-ring keratoscope with a concentric grid array for the study of higher-order aberrations, additional work is required to establish better control of the vertex distance. The handheld open-field infant keratometer demonstrates testability suitable for the study of infant corneal astigmatism. Use of collimated light sources in future iterations of the design must be incorporated in order to achieve the accuracy required for clinical investigation.

Effect of matching between the magnetic field and channel length on the performance of low sputtering Hall thrusters

NASA Astrophysics Data System (ADS)

Ding, Yongjie; Boyang, Jia; Sun, Hezhi; Wei, Liqiu; Peng, Wuji; Li, Peng; Yu, Daren

2018-02-01

Discharge characteristics of a non-wall-loss Hall thruster were studied under different channel lengths using a design based on pushing a magnetic field through a double permanent magnet ring. The effect of different magnetic field intensities and channel lengths on ionization, efficiency, and plume divergence angle were studied. The experimental results show that propellant utilization is improved for optimal matching between the magnetic field and channel length. While matching the magnetic field and channel length, the ionization position of the neutral gas changes. The ion flow is effectively controlled, allowing the thrust force, specific impulse, and efficiency to be improved. Our study shows that the channel length is an important design parameter to consider for improving the performance of non-wall-loss Hall thrusters.

A field test of three LQAS designs to assess the prevalence of acute malnutrition.

PubMed

Deitchler, Megan; Valadez, Joseph J; Egge, Kari; Fernandez, Soledad; Hennigan, Mary

2007-08-01

The conventional method for assessing the prevalence of Global Acute Malnutrition (GAM) in emergency settings is the 30 x 30 cluster-survey. This study describes alternative approaches: three Lot Quality Assurance Sampling (LQAS) designs to assess GAM. The LQAS designs were field-tested and their results compared with those from a 30 x 30 cluster-survey. Computer simulations confirmed that small clusters instead of a simple random sample could be used for LQAS assessments of GAM. Three LQAS designs were developed (33 x 6, 67 x 3, Sequential design) to assess GAM thresholds of 10, 15 and 20%. The designs were field-tested simultaneously with a 30 x 30 cluster-survey in Siraro, Ethiopia during June 2003. Using a nested study design, anthropometric, morbidity and vaccination data were collected on all children 6-59 months in sampled households. Hypothesis tests about GAM thresholds were conducted for each LQAS design. Point estimates were obtained for the 30 x 30 cluster-survey and the 33 x 6 and 67 x 3 LQAS designs. Hypothesis tests showed GAM as <10% for the 33 x 6 design and GAM as > or =10% for the 67 x 3 and Sequential designs. Point estimates for the 33 x 6 and 67 x 3 designs were similar to those of the 30 x 30 cluster-survey for GAM (6.7%, CI = 3.2-10.2%; 8.2%, CI = 4.3-12.1%, 7.4%, CI = 4.8-9.9%) and all other indicators. The CIs for the LQAS designs were only slightly wider than the CIs for the 30 x 30 cluster-survey; yet the LQAS designs required substantially less time to administer. The LQAS designs provide statistically appropriate alternatives to the more time-consuming 30 x 30 cluster-survey. However, additional field-testing is needed using independent samples rather than a nested study design.

An Overview of Hardware for Protein Crystallization in a Magnetic Field.

PubMed

Yan, Er-Kai; Zhang, Chen-Yan; He, Jin; Yin, Da-Chuan

2016-11-16

Protein crystallization under a magnetic field is an interesting research topic because a magnetic field may provide a special environment to acquire improved quality protein crystals. Because high-quality protein crystals are very useful in high-resolution structure determination using diffraction techniques (X-ray, neutron, and electron diffraction), research using magnetic fields in protein crystallization has attracted substantial interest; some studies have been performed in the past two decades. In this research field, the hardware is especially essential for successful studies because the environment is special and the design and utilization of the research apparatus in such an environment requires special considerations related to the magnetic field. This paper reviews the hardware for protein crystallization (including the magnet systems and the apparatus designed for use in a magnetic field) and progress in this area. Future prospects in this field will also be discussed.

A fast field-cycling device for high-resolution NMR: Design and application to spin relaxation and hyperpolarization experiments

NASA Astrophysics Data System (ADS)

Kiryutin, Alexey S.; Pravdivtsev, Andrey N.; Ivanov, Konstantin L.; Grishin, Yuri A.; Vieth, Hans-Martin; Yurkovskaya, Alexandra V.

2016-02-01

A device for performing fast magnetic field-cycling NMR experiments is described. A key feature of this setup is that it combines fast switching of the external magnetic field and high-resolution NMR detection. The field-cycling method is based on precise mechanical positioning of the NMR probe with the mounted sample in the inhomogeneous fringe field of the spectrometer magnet. The device enables field variation over several decades (from 100 μT up to 7 T) within less than 0.3 s; progress in NMR probe design provides NMR linewidths of about 10-3 ppm. The experimental method is very versatile and enables site-specific studies of spin relaxation (NMRD, LLSs) and spin hyperpolarization (DNP, CIDNP, and SABRE) at variable magnetic field and at variable temperature. Experimental examples of such studies are demonstrated; advantages of the experimental method are described and existing challenges in the field are outlined.

An Overview of Hardware for Protein Crystallization in a Magnetic Field

PubMed Central

Yan, Er-Kai; Zhang, Chen-Yan; He, Jin; Yin, Da-Chuan

2016-01-01

Protein crystallization under a magnetic field is an interesting research topic because a magnetic field may provide a special environment to acquire improved quality protein crystals. Because high-quality protein crystals are very useful in high-resolution structure determination using diffraction techniques (X-ray, neutron, and electron diffraction), research using magnetic fields in protein crystallization has attracted substantial interest; some studies have been performed in the past two decades. In this research field, the hardware is especially essential for successful studies because the environment is special and the design and utilization of the research apparatus in such an environment requires special considerations related to the magnetic field. This paper reviews the hardware for protein crystallization (including the magnet systems and the apparatus designed for use in a magnetic field) and progress in this area. Future prospects in this field will also be discussed. PMID:27854318

The presence of field geologists in Mars-like terrain

NASA Technical Reports Server (NTRS)

Mcgreevy, Michael W.

1992-01-01

Methods of ethnographic observation and analysis have been coupled with object-oriented analysis and design concepts to begin the development of a clear path from observations in the field to the design of virtual presence systems. The existence of redundancies in field geology and presence allowed for the application of methods for understanding complex systems. As a result of this study, some of these redundancies have been characterized. Those described are all classes of continuity relations, including the continuities of continuous existence, context-constituent continuities, and state-process continuities. The discussion of each includes statements of general relationships, logical consequences of these, and hypothetical situations in which the relationships would apply. These are meant to aid in the development of a theory of presence. The discussion also includes design considerations, providing guidance for the design of virtual planetary exploration systems and other virtual presence systems. Converging evidence regarding continuity in presence is found in the nature of psychological dissociation. Specific methodological refinements should enhance ecological validity in subsequent field studies, which are in progress.

Quasi-experimental Studies in the Fields of Infection Control and Antibiotic Resistance, Ten Years Later: A Systematic Review.

PubMed

Alsaggaf, Rotana; O'Hara, Lyndsay M; Stafford, Kristen A; Leekha, Surbhi; Harris, Anthony D

2018-02-01

OBJECTIVE A systematic review of quasi-experimental studies in the field of infectious diseases was published in 2005. The aim of this study was to assess improvements in the design and reporting of quasi-experiments 10 years after the initial review. We also aimed to report the statistical methods used to analyze quasi-experimental data. DESIGN Systematic review of articles published from January 1, 2013, to December 31, 2014, in 4 major infectious disease journals. METHODS Quasi-experimental studies focused on infection control and antibiotic resistance were identified and classified based on 4 criteria: (1) type of quasi-experimental design used, (2) justification of the use of the design, (3) use of correct nomenclature to describe the design, and (4) statistical methods used. RESULTS Of 2,600 articles, 173 (7%) featured a quasi-experimental design, compared to 73 of 2,320 articles (3%) in the previous review (P<.01). Moreover, 21 articles (12%) utilized a study design with a control group; 6 (3.5%) justified the use of a quasi-experimental design; and 68 (39%) identified their design using the correct nomenclature. In addition, 2-group statistical tests were used in 75 studies (43%); 58 studies (34%) used standard regression analysis; 18 (10%) used segmented regression analysis; 7 (4%) used standard time-series analysis; 5 (3%) used segmented time-series analysis; and 10 (6%) did not utilize statistical methods for comparisons. CONCLUSIONS While some progress occurred over the decade, it is crucial to continue improving the design and reporting of quasi-experimental studies in the fields of infection control and antibiotic resistance to better evaluate the effectiveness of important interventions. Infect Control Hosp Epidemiol 2018;39:170-176.

Physical barriers formed from gelling liquids: 1. numerical design of laboratory and field experiments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Finsterle, S.; Moridis, G.J.; Pruess, K.

1994-01-01

The emplacement of liquids under controlled viscosity conditions is investigated by means of numerical simulations. Design calculations are performed for a laboratory experiment on a decimeter scale, and a field experiment on a meter scale. The purpose of the laboratory experiment is to study the behavior of multiple gout plumes when injected in a porous medium. The calculations for the field trial aim at designing a grout injection test from a vertical well in order to create a grout plume of a significant extent in the subsurface.

Optical design of an athermalised dual field of view step zoom optical system in MWIR

NASA Astrophysics Data System (ADS)

Kucukcelebi, Doruk

2017-08-01

In this paper, the optical design of an athermalised dual field of view step zoom optical system in MWIR (3.7μm - 4.8μm) is described. The dual field of view infrared optical system is designed based on the principle of passive athermalization method not only to achieve athermal optical system but also to keep the high image quality within the working temperature between -40°C and +60°C. The infrared optical system used in this study had a 320 pixel x 256 pixel resolution, 20μm pixel pitch size cooled MWIR focal plane array detector. In this study, the step zoom mechanism, which has the axial motion due to consisting of a lens group, is considered to simplify mechanical structure. The optical design was based on moving a single lens along the optical axis for changing the optical system's field of view not only to reduce the number of moving parts but also to athermalize for the optical system. The optical design began with an optimization process using paraxial optics when first-order optics parameters are determined. During the optimization process, in order to reduce aberrations, such as coma, astigmatism, spherical and chromatic aberrations, aspherical surfaces were used. As a result, athermalised dual field of view step zoom optical design is proposed and the performance of the design using proposed method was verified by providing the focus shifts, spot diagrams and MTF analyzes' plots.

The Metamorphosis of Industrial Designers from Novices to Experts

ERIC Educational Resources Information Center

Wong, Ju-Joan; Chen, Po-Yu; Chen, Chun-Di

2016-01-01

Professional training for designers is crucial in the field of design studies. The characteristics of novices versus those of expert designers have been identified in the literature; however, studies exploring the issue of professional training processes in the actual workplace are not well developed. Our study addresses the topic by using…

EXPERIMENTAL DESIGN AND INSTRUMENTATION FOR A FIELD EXPERIMENT

EPA Science Inventory

This report concerns the design of a field experiment for a military setting in which the effects of carbon monoxide on neurobehavioral variables are to be studied. ield experiment is distinguished from a survey by the fact that independent variables are manipulated, just as in t...

Empirical studies of software design: Implications for SSEs

NASA Technical Reports Server (NTRS)

Krasner, Herb

1988-01-01

Implications for Software Engineering Environments (SEEs) are presented in viewgraph format for characteristics of projects studied; significant problems and crucial problem areas in software design for large systems; layered behavioral model of software processes; implications of field study results; software project as an ecological system; results of the LIFT study; information model of design exploration; software design strategies; results of the team design study; and a list of publications.

Sampling flies or sampling flaws? Experimental design and inference strength in forensic entomology.

PubMed

Michaud, J-P; Schoenly, Kenneth G; Moreau, G

2012-01-01

Forensic entomology is an inferential science because postmortem interval estimates are based on the extrapolation of results obtained in field or laboratory settings. Although enormous gains in scientific understanding and methodological practice have been made in forensic entomology over the last few decades, a majority of the field studies we reviewed do not meet the standards for inference, which are 1) adequate replication, 2) independence of experimental units, and 3) experimental conditions that capture a representative range of natural variability. Using a mock case-study approach, we identify design flaws in field and lab experiments and suggest methodological solutions for increasing inference strength that can inform future casework. Suggestions for improving data reporting in future field studies are also proposed.

Using Mobile Devices to Connect Teachers and Museum Educators

NASA Astrophysics Data System (ADS)

Delen, Ibrahim; Krajcik, Joseph

2017-06-01

The use of mobile devices is increasing rapidly as a potential tool for science teaching. In this study, five educators (three middle school teachers and two museum educators) used a mobile application that supported the development of a driving question. Previous studies have noted that teachers make little effort to connect learning experiences between classrooms and museums, and few studies have focused on creating connections between teachers and museum educators. In this study, teachers and museum educators created an investigation together by designing a driving question in conjunction with the research group before field trips. During field trips, students collected their own data using iPods or iPads to take pictures or record videos of the exhibits. When students returned to the school, they used the museum data with their peers as they tried to answer the driving question. After completing the field trips, five educators were interviewed to investigate their experiences with designing driving questions and using mobile devices. Besides supporting students in data collection during the field trip, using mobile devices helped teachers to get the museum back to the classroom. Designing the driving question supported museum educators and teachers to plan the field trip collaboratively.

Creating and validating GIS measures of urban design for health research.

PubMed

Purciel, Marnie; Neckerman, Kathryn M; Lovasi, Gina S; Quinn, James W; Weiss, Christopher; Bader, Michael D M; Ewing, Reid; Rundle, Andrew

2009-12-01

Studies relating urban design to health have been impeded by the unfeasibility of conducting field observations across large areas and the lack of validated objective measures of urban design. This study describes measures for five dimensions of urban design - imageability, enclosure, human scale, transparency, and complexity - created using public geographic information systems (GIS) data from the US Census and city and state government. GIS measures were validated for a sample of 588 New York City block faces using a well-documented field observation protocol. Correlations between GIS and observed measures ranged from 0.28 to 0.89. Results show valid urban design measures can be constructed from digital sources.

Creating and validating GIS measures of urban design for health research

PubMed Central

Purciel, Marnie; Neckerman, Kathryn M.; Lovasi, Gina S.; Quinn, James W.; Weiss, Christopher; Bader, Michael D.M.; Ewing, Reid; Rundle, Andrew

2012-01-01

Studies relating urban design to health have been impeded by the unfeasibility of conducting field observations across large areas and the lack of validated objective measures of urban design. This study describes measures for five dimensions of urban design – imageability, enclosure, human scale, transparency, and complexity – created using public geographic information systems (GIS) data from the US Census and city and state government. GIS measures were validated for a sample of 588 New York City block faces using a well-documented field observation protocol. Correlations between GIS and observed measures ranged from 0.28 to 0.89. Results show valid urban design measures can be constructed from digital sources. PMID:22956856

Analysis of an Adjustable Field Permanent Magnet Solenoid

DOE PAGES

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

Influence of Study Design on Outcomes Following Reflexology Massage: An Integrative and Critical Review of Interventional Studies.

PubMed

McVicar, Andrew; Greenwood, Christina; Ellis, Carol; LeForis, Chantelle

2016-09-01

Interpretation of the efficacy of reflexology is hindered by inconsistent research designs and complicated by professional views that criteria of randomized controlled trials (RCTs)are not ideal to research holistic complementary and alternative medicine practice. The influence of research designs on study outcomes is not known. This integrative review sought to evaluate this possibility. Thirty-seven interventional studies (2000-2014) were identified; they had RCT or non-RCT design and compared reflexology outcomes against a control/comparison group. Viability of integrating RCT and non-RCT studies into a single database was first evaluated by appraisal of 16 reporting fields related to study setting and objectives, sample demographics, methodologic design, and treatment fidelity and assessment against Jadad score quality criteria for RCTs. For appraisal, the database was stratified into RCT/non-RCT or Jadad score of 3 or more or less than 3. Deficits in reporting were identified for blind assignment of participants, dropout/completion rate, and School of Reflexology. For comparison purposes, these fields were excluded from subsequent analysis for evidence of association between design fields and of fields with study outcomes. Thirty-one studies applied psychometric tools and 20 applied biometric tools (14 applied both). A total of 116 measures were used. Type of measure was associated with study objectives (p < 0.001; chi-square), in particular of psychometric measures with a collated "behavioral/cognitive" objective. Significant outcomes were more likely (p < 0.001; chi-square) for psychometric than for biometric measures. Neither type of outcome was associated with choice of RCT or non-RCT method, but psychometric responses were associated (p = 0.007) with a nonmassage control strategy. The review supports psychometric responses to reflexology when study design uses a nonmassage control strategy. Findings suggest that an evaluation of outcomes against sham reflexology massage and other forms of massage, as well as a narrower focus of study objective, may clarify whether there is a relationship between study design and efficacy of reflexology.

The effect of passive mixing on pressure drop and oxygen mass fraction using opposing channel flow field design in a Proton Exchange Membrane Fuel Cell

NASA Astrophysics Data System (ADS)

Singh, Anant Bir

This study investigates a flow field with opposing channel design. Previous studies on flow field designs have been focused on improving fuel utilization which often leads to increased pressure drop. This increased pressure drop is typical because standard designs employ either a single flow channel to clear blockages or dead end condition to force the flow through the gas diffusion layer. The disadvantage with these designs is the increased resistance to the flow which requires higher pressure, which becomes a parasitic loss that lowers the system efficiency. For this study the focus was to reduce the pressure drop by providing a less resistive path to the flow. To achieve a less resistive path, the inlet channel was split into two opposing channels. These channels are then recombined only to be split again for the next leg. Therefore, the split channel design should reduce the pressure drop which reduces the parasitic load and ultimately contributes to higher system efficiency. In addition the recombining of the streams at each leg should induce mixing. Having opposing channels should also increase cross flow under the lands to reduce mass transfer loses. The cathode side of the fuel cell is especially sensitive to the mass transport losses since air (oxygen mixed with nitrogen) is used for supplying oxygen unlike the anode side which uses pure hydrogen. To test the hypothesis of having benefits from an opposing channel design, both an experimental and analytical approach was taken. For the experiment, a serpentine flow field and opposing channel flow field plates were compared over several flow rates with compressed air. To test the hypothesis of increased mass transfer, the two flow fields were modeled using a CFD software package, COMSOL. It was found that the opposing channel configuration for high flow rate with multiple entry and exit conditions exhibited significant improvement over the single serpentine channel. Pressure drop was ⅓ less than the serpentine channel with similar conditions. Simulations for mass transfer show that recombining of the flow streams generate more uniform current density unlike the serpentine configuration where the current density was concentrated at the entrance of the flow stream. The background section provides a brief overview of the governing equations, the theory of flow field operation and previous bodies of work on flow field design. Recommendations are made for further verification of the design using a real working cell based on the results.

Shape design sensitivity analysis using domain information

NASA Technical Reports Server (NTRS)

Seong, Hwal-Gyeong; Choi, Kyung K.

1985-01-01

A numerical method for obtaining accurate shape design sensitivity information for built-up structures is developed and demonstrated through analysis of examples. The basic character of the finite element method, which gives more accurate domain information than boundary information, is utilized for shape design sensitivity improvement. A domain approach for shape design sensitivity analysis of built-up structures is derived using the material derivative idea of structural mechanics and the adjoint variable method of design sensitivity analysis. Velocity elements and B-spline curves are introduced to alleviate difficulties in generating domain velocity fields. The regularity requirements of the design velocity field are studied.

Educating Instructional Designers: Different Methods for Different Outcomes.

ERIC Educational Resources Information Center

Rowland, Gordon; And Others

1994-01-01

Suggests new methods of teaching instructional design based on literature reviews of other design fields including engineering, architecture, interior design, media design, and medicine. Methods discussed include public presentations, visiting experts, competitions, artifacts, case studies, design studios, and internships and apprenticeships.…

Magnetic field design for a Penning ion source for a 200 keV electrostatic accelerator

NASA Astrophysics Data System (ADS)

Fathi, A.; Feghhi, S. A. H.; Sadati, S. M.; Ebrahimibasabi, E.

2017-04-01

In this study, the structure of magnetic field for a Penning ion source has been designed and constructed with the use of permanent magnets. The ion source has been designed and constructed for a 200 keV electrostatic accelerator. With using CST Studio Suite, the magnetic field profile inside the ion source was simulated and an appropriate magnetic system was designed to improve particle confinement. Designed system consists of two ring magnets with 9 mm distance from each other around the anode. The ion source was constructed and the cylindrical magnet and designed magnetic system were tested on the ion source. The results showed that the ignition voltage for ion source with the designed magnetic system is almost 300 V lower than the ion source with the cylindrical magnet. Better particle confinement causes lower voltage discharge to occur.

Echoes from the Field: An Ethnographic Investigation of Outdoor Science Field Trips

NASA Astrophysics Data System (ADS)

Boxerman, Jonathan Zvi

As popular as field trips are, one might think they have been well-studied. Nonetheless, field trips have not been heavily studied, and little research has mapped what actually transpires during field trips. Accordingly, to address this research gap, I asked two related research questions. The first question is a descriptive one: What happens on field trips? The second question is explanatory: What field trip events are memorable and why? I employed design research and ethnographic methodologies to study learning in naturally occurring contexts. I collaborated with middle-school science teachers to design and implement more than a dozen field trips. The field trips were nested in particular biology and earth sciences focal units. Students were tasked with making scientific observations in the field and then analyzing this data during classroom activities. Audio and video recording devices captured what happened during the field trips, classroom activities and discussions, and the interviews. I conducted comparative microanalysis of videotaped interactions. I observed dozens of events during the field trips that reverberated across time and place. I characterize the features of these events and the objects that drew interest. Then, I trace the residue across contexts. This study suggests that field trips could be more than one-off experiences and have the potential to be resources to seed and enrich learning and to augment interest in the practice of science.

The Design and Implementation of Indoor Localization System Using Magnetic Field Based on Smartphone

NASA Astrophysics Data System (ADS)

Liu, J.; Jiang, C.; Shi, Z.

2017-09-01

Sufficient signal nodes are mostly required to implement indoor localization in mainstream research. Magnetic field take advantage of high precision, stable and reliability, and the reception of magnetic field signals is reliable and uncomplicated, it could be realized by geomagnetic sensor on smartphone, without external device. After the study of indoor positioning technologies, choose the geomagnetic field data as fingerprints to design an indoor localization system based on smartphone. A localization algorithm that appropriate geomagnetic matching is designed, and present filtering algorithm and algorithm for coordinate conversion. With the implement of plot geomagnetic fingerprints, the indoor positioning of smartphone without depending on external devices can be achieved. Finally, an indoor positioning system which is based on Android platform is successfully designed, through the experiments, proved the capability and effectiveness of indoor localization algorithm.

Design study of superconducting magnets for a combustion magnetohydrodynamic (MHD) generator

NASA Technical Reports Server (NTRS)

Thome, R. J.; Ayers, J. W.

1977-01-01

Design trade off studies for 13 different superconducting magnet systems were carried out. Based on these results, preliminary design characteristics were prepared for several superconducting magnet systems suitable for use with a combustion driven MHD generator. Each magnet generates a field level of 8 T in a volume 1.524 m (60 in.) long with a cross section 0.254 m x 0.254 m (10 in. x 10 in.) at the inlet and 0.406 m x .406 m (16 in. x 16 in.) at the outlet. The first design involves a racetrack coil geometry intended for operation at 4.2 K; the second design uses a racetrack geometry at 2.0 K; and the third design utilizes a rectangular saddle geometry at 4.2 K. Each case was oriented differently in terms of MHD channel axis and main field direction relative to gravity in order to evaluate fabrication ease. All cases were designed such that the system could be disassembled to allow for alteration of field gradient in the MHD channel by changing the angle between coils. Preliminary design characteristics and assembly drawings were generated for each case.

Parametric design of tri-axial nested Helmholtz coils

NASA Astrophysics Data System (ADS)

Abbott, Jake J.

2015-05-01

This paper provides an optimal parametric design for tri-axial nested Helmholtz coils, which are used to generate a uniform magnetic field with controllable magnitude and direction. Circular and square coils, both with square cross section, are considered. Practical considerations such as wire selection, wire-wrapping efficiency, wire bending radius, choice of power supply, and inductance and time response are included. Using the equations provided, a designer can quickly create an optimal set of custom coils to generate a specified field magnitude in the uniform-field region while maintaining specified accessibility to the central workspace. An example case study is included.

Parametric design of tri-axial nested Helmholtz coils.

PubMed

Abbott, Jake J

2015-05-01

This paper provides an optimal parametric design for tri-axial nested Helmholtz coils, which are used to generate a uniform magnetic field with controllable magnitude and direction. Circular and square coils, both with square cross section, are considered. Practical considerations such as wire selection, wire-wrapping efficiency, wire bending radius, choice of power supply, and inductance and time response are included. Using the equations provided, a designer can quickly create an optimal set of custom coils to generate a specified field magnitude in the uniform-field region while maintaining specified accessibility to the central workspace. An example case study is included.

Parametric design of tri-axial nested Helmholtz coils

DOE Office of Scientific and Technical Information (OSTI.GOV)

Abbott, Jake J., E-mail: jake.abbott@utah.edu

This paper provides an optimal parametric design for tri-axial nested Helmholtz coils, which are used to generate a uniform magnetic field with controllable magnitude and direction. Circular and square coils, both with square cross section, are considered. Practical considerations such as wire selection, wire-wrapping efficiency, wire bending radius, choice of power supply, and inductance and time response are included. Using the equations provided, a designer can quickly create an optimal set of custom coils to generate a specified field magnitude in the uniform-field region while maintaining specified accessibility to the central workspace. An example case study is included.

The effects of the interaction between cognitive style and instructional strategy on the educational outcomes for a science exhibit

NASA Astrophysics Data System (ADS)

Knappenberger, Naomi

This dissertation examines factors which may affect the educational effectiveness of science exhibits. Exhibit effectiveness is the result of a complex interaction among exhibit features, cognitive characteristics of the museum visitor, and educational outcomes. The purpose of this study was to determine the relative proportions of field-dependent and field-independent visitors in the museum audience, and to ascertain if the cognitive style of visitors interacted with instructional strategies to affect the educational outcomes for a computer-based science exhibit. Cognitive style refers to the self-consistent modes of selecting and processing information that an individual employs throughout his or her perceptual and intellectual activities. It has a broad influence on many aspects of personality and behavior, including perception, memory, problem solving, interest, and even social behaviors and self-concept. As such, it constitutes essential dimensions of individual differences among museum visitors and has important implications for instructional design in the museum. The study was conducted in the spring of 1998 at the Adler Planetarium and Astronomy Museum in Chicago. Two experimental treatments of a computer-based exhibit were tested in the study. The first experimental treatment utilized strategies designed for field-dependent visitors that limited the text and provided more structure and cueing than the baseline treatment of the computer program. The other experimental treatment utilized strategies designed for field-independent visitors that provided hypothesis-testing and more contextual information. Approximately two-thirds of the visitors were field-independent. The results of a multiple regression analysis indicated that there was a significant interaction between cognitive style and instructional strategy that affected visitors' posttest scores on a multiple-choice test of the content. Field-independent visitors out- performed the field-dependent visitors in the control, baseline, and both experimental treatments. Both field-dependent and field-independent visitor posttest scores increased in the field-dependent experimental treatment and in the field-independent treatment. The most effective treatment for all visitors was the field-independent treatment. Criteria for designing a computer-based exhibit to meet the needs of all visitors were recommended. These included organized, concise text; a structured, rather than exploratory design; and cueing in the form of questions, bold fonts, underlining of important words and concepts, and captioned images.

Impact of spatial variability and sampling design on model performance

NASA Astrophysics Data System (ADS)

Schrape, Charlotte; Schneider, Anne-Kathrin; Schröder, Boris; van Schaik, Loes

2017-04-01

Many environmental physical and chemical parameters as well as species distributions display a spatial variability at different scales. In case measurements are very costly in labour time or money a choice has to be made between a high sampling resolution at small scales and a low spatial cover of the study area or a lower sampling resolution at the small scales resulting in local data uncertainties with a better spatial cover of the whole area. This dilemma is often faced in the design of field sampling campaigns for large scale studies. When the gathered field data are subsequently used for modelling purposes the choice of sampling design and resulting data quality influence the model performance criteria. We studied this influence with a virtual model study based on a large dataset of field information on spatial variation of earthworms at different scales. Therefore we built a virtual map of anecic earthworm distributions over the Weiherbach catchment (Baden-Württemberg in Germany). First of all the field scale abundance of earthworms was estimated using a catchment scale model based on 65 field measurements. Subsequently the high small scale variability was added using semi-variograms, based on five fields with a total of 430 measurements divided in a spatially nested sampling design over these fields, to estimate the nugget, range and standard deviation of measurements within the fields. With the produced maps, we performed virtual samplings of one up to 50 random points per field. We then used these data to rebuild the catchment scale models of anecic earthworm abundance with the same model parameters as in the work by Palm et al. (2013). The results of the models show clearly that a large part of the non-explained deviance of the models is due to the very high small scale variability in earthworm abundance: the models based on single virtual sampling points on average obtain an explained deviance of 0.20 and a correlation coefficient of 0.64. With increasing sampling points per field, we averaged the measured abundance of the sampling within each field to obtain a more representative value of the field average. Doubling the samplings per field strongly improved the model performance criteria (explained deviance 0.38 and correlation coefficient 0.73). With 50 sampling points per field the performance criteria were 0.91 and 0.97 respectively for explained deviance and correlation coefficient. The relationship between number of samplings and performance criteria can be described with a saturation curve. Beyond five samples per field the model improvement becomes rather small. With this contribution we wish to discuss the impact of data variability at sampling scale on model performance and the implications for sampling design and assessment of model results as well as ecological inferences.

Design of 2D time-varying vector fields.

PubMed

Chen, Guoning; Kwatra, Vivek; Wei, Li-Yi; Hansen, Charles D; Zhang, Eugene

2012-10-01

Design of time-varying vector fields, i.e., vector fields that can change over time, has a wide variety of important applications in computer graphics. Existing vector field design techniques do not address time-varying vector fields. In this paper, we present a framework for the design of time-varying vector fields, both for planar domains as well as manifold surfaces. Our system supports the creation and modification of various time-varying vector fields with desired spatial and temporal characteristics through several design metaphors, including streamlines, pathlines, singularity paths, and bifurcations. These design metaphors are integrated into an element-based design to generate the time-varying vector fields via a sequence of basis field summations or spatial constrained optimizations at the sampled times. The key-frame design and field deformation are also introduced to support other user design scenarios. Accordingly, a spatial-temporal constrained optimization and the time-varying transformation are employed to generate the desired fields for these two design scenarios, respectively. We apply the time-varying vector fields generated using our design system to a number of important computer graphics applications that require controllable dynamic effects, such as evolving surface appearance, dynamic scene design, steerable crowd movement, and painterly animation. Many of these are difficult or impossible to achieve via prior simulation-based methods. In these applications, the time-varying vector fields have been applied as either orientation fields or advection fields to control the instantaneous appearance or evolving trajectories of the dynamic effects.

Design, construction and calibration of a portable boundary layer wind tunnel for field use

USDA-ARS?s Scientific Manuscript database

Wind tunnels have been used for several decades to study wind erosion processes. Portable wind tunnels offer the advantage of testing natural surfaces in the field, but they must be carefully designed to insure that a logarithmic boundary layer is formed and that wind erosion processes may develop ...

Designing and Evaluating Research-Based Instructional Sequences for Introducing Magnetic Fields

ERIC Educational Resources Information Center

Guisasola, Jenaro; Almudi, Jose Manuel; Ceberio, Mikel; Zubimendi, Jose Luis

2009-01-01

This study examines the didactic suitability of introducing a teaching sequence when teaching the concept of magnetic fields within introductory physics courses at the university level. This instructional sequence was designed taking into account students' common conceptions, an analysis of the course content, and the history of the development of…

The Attitudes of Field Dependence Learners for Learner Interface Design (LID) in e-Learning Instruction

ERIC Educational Resources Information Center

Sözcü, Ömer Faruk; Ipek, Ismail; Kinay, Hüseyin

2016-01-01

The purpose of the study is to explore relationships between learners' cognitive styles of field dependence and learner variables in the preference of learner Interface design, attitudes in e-Learning instruction and experience with e-Learning in distance education. Cognitive style has historically referred to a psychological dimension…

A Computational and Experimental Investigation of a Three-Dimensional Hypersonic Scramjet Inlet Flow Field. Ph.D. Thesis

NASA Technical Reports Server (NTRS)

Holland, Scott Douglas

1991-01-01

A combined computational and experimental parametric study of the internal aerodynamics of a generic three dimensional sidewall compression scramjet inlet configuration was performed. The study was designed to demonstrate the utility of computational fluid dynamics as a design tool in hypersonic inlet flow fields, to provide a detailed account of the nature and structure of the internal flow interactions, and to provide a comprehensive surface property and flow field database to determine the effects of contraction ratio, cowl position, and Reynolds number on the performance of a hypersonic scramjet inlet configuration.

Design Studies and Optimization of High-Field Nb$$_3$$Sn Dipole Magnets for a Future Very High Energy PP Collider

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kashikhin, V. V.; Novitski, I.; Zlobin, A. V.

2017-05-01

High filed accelerator magnets with operating fields of 15-16 T based on themore » $$Nb_3Sn$$ superconductor are being considered for the LHC energy upgrade or a future Very High Energy pp Collider. Magnet design studies are being conducted in the U.S., Europe and Asia to explore the limits of the $$Nb_3Sn$$ accelerator magnet technology while optimizing the magnet design and performance parame-ters, and reducing magnet cost. The first results of these studies performed at Fermilab in the framework of the US-MDP are reported in this paper.« less

A Critical Review of Instructional Design Process of Distance Learning System

ERIC Educational Resources Information Center

Chaudry, Muhammad Ajmal; ur-Rahman, Fazal

2010-01-01

Instructional design refers to planning, development, delivery and evaluation of instructional system. It is an applied field of study aiming at the application of descriptive research outcomes in regular instructional settings. The present study was designed to critically review the process of instructional design at Allama Iqbal Open University…

A spiral, bi-planar gradient coil design for open magnetic resonance imaging.

PubMed

Zhang, Peng; Shi, Yikai; Wang, Wendong; Wang, Yaohui

2018-01-01

To design planar gradient coil for MRI applications without discretization of continuous current density and loop-loop connection errors. In the new design method, the coil current is represented using a spiral curve function described by just a few control parameters. Using a proper parametric equation set, an ensemble of spiral contours is reshaped to satisfy the coil design requirements, such as gradient linearity, inductance and shielding. In the given case study, by using the spiral coil design, the magnetic field errors in the imaging area were reduced from 5.19% (non-spiral design) to 4.47% (spiral design) for the transverse gradient coils, and for the longitudinal gradient coil design, the magnetic field errors were reduced to 5.02% (spiral design). The numerical evaluation shows that when compared with conventional wire loop, the inductance and resistance of spiral coil was reduced by 11.55% and 8.12% for x gradient coil, respectively. A novel spiral gradient coil design for biplanar MRI systems, the new design offers better magnetic field gradients, smooth contours than the conventional connected counterpart, which improves manufacturability.

Comparison study of toroidal-field divertors for a compact reversed-field pinch reactor

NASA Astrophysics Data System (ADS)

Bathke, C. G.; Krakowski, R. A.; Miller, R. L.

Two divertor configurations for the Compact Reversed-Field Pinch Reactor (CRFPR) based on diverting the minority (toroidal) field have been reported. A critical factor in evaluating the performance of both poloidally symmetric and bundle divertor configurations is the accurate determination of the divertor connection length and the monitoring of magnetic islands introduced by the divertors, the latter being a three-dimensional effect. To this end the poloidal-field, toroidal-field, and divertor coils and the plasma currents are simulated in three dimensions for field-line trackings in both the divertor channel and the plasma-edge regions. The results of this analysis indicate a clear preference for the poloidally symmetric toroidal-field divertor. Design modifications to the limiter-based CRFPR design that accommodate this divertor are presented.

Design of shared instruments to utilize simulated gravities generated by a large-gradient, high-field superconducting magnet.

PubMed

Wang, Y; Yin, D C; Liu, Y M; Shi, J Z; Lu, H M; Shi, Z H; Qian, A R; Shang, P

2011-03-01

A high-field superconducting magnet can provide both high-magnetic fields and large-field gradients, which can be used as a special environment for research or practical applications in materials processing, life science studies, physical and chemical reactions, etc. To make full use of a superconducting magnet, shared instruments (the operating platform, sample holders, temperature controller, and observation system) must be prepared as prerequisites. This paper introduces the design of a set of sample holders and a temperature controller in detail with an emphasis on validating the performance of the force and temperature sensors in the high-magnetic field.

Design of shared instruments to utilize simulated gravities generated by a large-gradient, high-field superconducting magnet

NASA Astrophysics Data System (ADS)

Wang, Y.; Yin, D. C.; Liu, Y. M.; Shi, J. Z.; Lu, H. M.; Shi, Z. H.; Qian, A. R.; Shang, P.

2011-03-01

A high-field superconducting magnet can provide both high-magnetic fields and large-field gradients, which can be used as a special environment for research or practical applications in materials processing, life science studies, physical and chemical reactions, etc. To make full use of a superconducting magnet, shared instruments (the operating platform, sample holders, temperature controller, and observation system) must be prepared as prerequisites. This paper introduces the design of a set of sample holders and a temperature controller in detail with an emphasis on validating the performance of the force and temperature sensors in the high-magnetic field.

PISCES: An Integral Field Spectrograph Technology Demonstration for the WFIRST Coronagraph

NASA Technical Reports Server (NTRS)

McElwain, Michael W.; Mandell, Avi M.; Gong, Qian; Llop-Sayson, Jorge; Brandt, Timothy; Chambers, Victor J.; Grammer, Bryan; Greeley, Bradford; Hilton, George; Perrin, Marshall D.;

PISCES: an integral field spectrograph technology demonstration for the WFIRST coronagraph

NASA Astrophysics Data System (ADS)

McElwain, Michael W.; Mandell, Avi M.; Gong, Qian; Llop-Sayson, Jorge; Brandt, Timothy; Chambers, Victor J.; Grammer, Bryan; Greeley, Bradford; Hilton, George; Perrin, Marshall D.; Stapelfeldt, Karl R.; Demers, Richard; Tang, Hong; Cady, Eric

2016-07-01

We present the design, integration, and test of the Prototype Imaging Spectrograph for Coronagraphic Exoplanet Studies (PISCES) integral field spectrograph (IFS). The PISCES design meets the science requirements for the Wide-Field InfraRed Survey Telescope (WFIRST) Coronagraph Instrument (CGI). PISCES was integrated and tested in the integral field spectroscopy laboratory at NASA Goddard. In June 2016, PISCES was delivered to the Jet Propulsion Laboratory (JPL) where it was integrated with the Shaped Pupil Coronagraph (SPC) High Contrast Imaging Testbed (HCIT). The SPC/PISCES configuration will demonstrate high contrast integral field spectroscopy as part of the WFIRST CGI technology development program.

Design Optimisation of a Magnetic Field Based Soft Tactile Sensor

PubMed Central

Raske, Nicholas; Kow, Junwai; Alazmani, Ali; Ghajari, Mazdak; Culmer, Peter; Hewson, Robert

2017-01-01

This paper investigates the design optimisation of a magnetic field based soft tactile sensor, comprised of a magnet and Hall effect module separated by an elastomer. The aim was to minimise sensitivity of the output force with respect to the input magnetic field; this was achieved by varying the geometry and material properties. Finite element simulations determined the magnetic field and structural behaviour under load. Genetic programming produced phenomenological expressions describing these responses. Optimisation studies constrained by a measurable force and stable loading conditions were conducted; these produced Pareto sets of designs from which the optimal sensor characteristics were selected. The optimisation demonstrated a compromise between sensitivity and the measurable force, a fabricated version of the optimised sensor validated the improvements made using this methodology. The approach presented can be applied in general for optimising soft tactile sensor designs over a range of applications and sensing modes. PMID:29099787

Optimizing Experimental Designs: Finding Hidden Treasure.

USDA-ARS?s Scientific Manuscript database

Classical experimental design theory, the predominant treatment in most textbooks, promotes the use of blocking designs for control of spatial variability in field studies and other situations in which there is significant variation among heterogeneity among experimental units. Many blocking design...

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.;

Front-end antenna system design for the ITER low-field-side reflectometer system using GENRAY ray tracing.

PubMed

Wang, G; Doyle, E J; Peebles, W A

2016-11-01

A monostatic antenna array arrangement has been designed for the microwave front-end of the ITER low-field-side reflectometer (LFSR) system. This paper presents details of the antenna coupling coefficient analyses performed using GENRAY, a 3-D ray tracing code, to evaluate the plasma height accommodation capability of such an antenna array design. Utilizing modeled data for the plasma equilibrium and profiles for the ITER baseline and half-field scenarios, a design study was performed for measurement locations varying from the plasma edge to inside the top of the pedestal. A front-end antenna configuration is recommended for the ITER LFSR system based on the results of this coupling analysis.

Understanding behavioral responses of fish to pheromones in natural freshwater environments

USGS Publications Warehouse

Johnson, Nicholas S.; Li, Weiming

2010-01-01

There is an abundance of experimental studies and reviews that describe odorant-mediated behaviors of fish in laboratory microcosms, but research in natural field conditions has received considerably less attention. Fish pheromone studies in laboratory settings can be highly productive and allow for controlled experimental designs; however, laboratory tanks and flumes often cannot replicate all the physical, physiological and social contexts associated with natural environments. Field experiments can be a critical step in affirming and enhancing understanding of laboratory discoveries and often implicate the ecological significance of pheromones employed by fishes. When findings from laboratory experiments have been further tested in field environments, often different and sometimes contradictory conclusions are found. Examples include studies of sea lamprey (Petromyzon marinus) mating pheromones and fish alarm substances. Here, we review field research conducted on fish pheromones and alarm substances, highlighting the following topics: (1) contradictory results obtained in laboratory and field experiments, (2) how environmental context and physiological status influences behavior, (3) challenges and constraints of aquatic field research and (4) innovative techniques and experimental designs that advance understanding of fish chemical ecology through field research.

Influence of architecture and material properties on vanadium redox flow battery performance

NASA Astrophysics Data System (ADS)

Houser, Jacob; Clement, Jason; Pezeshki, Alan; Mench, Matthew M.

2016-01-01

This publication reports a design optimization study of all-vanadium redox flow batteries (VRBs), including performance testing, distributed current measurements, and flow visualization. Additionally, a computational flow simulation is used to support the conclusions made from the experimental results. This study demonstrates that optimal flow field design is not simply related to the best architecture, but is instead a more complex interplay between architecture, electrode properties, electrolyte properties, and operating conditions which combine to affect electrode convective transport. For example, an interdigitated design outperforms a serpentine design at low flow rates and with a thin electrode, accessing up to an additional 30% of discharge capacity; but a serpentine design can match the available discharge capacity of the interdigitated design by increasing the flow rate or the electrode thickness due to differing responses between the two flow fields. The results of this study should be useful to design engineers seeking to optimize VRB systems through enhanced performance and reduced pressure drop.

Interior Design Supports Art Education: A Case Study

ERIC Educational Resources Information Center

Clemons, Stephanie A.

2006-01-01

Interior design, as a field of study, is a rapidly growing area of interest--particularly for teenagers in the United States. Part of this interest stems from the proliferation of design-related reality shows available through television media. Some art educators and curriculum specialists in the nation perceive the study of interior spaces as a…

A Sphere-Scanning Radiometer for Rapid Directional Measurements of Sky and Ground Radiance: the PARABOLA Field Instrument

NASA Technical Reports Server (NTRS)

Deering, D. W.; Leone, P.

1984-01-01

A unique field instrument, called the PARABOLA, a collapsable support boom, which is self contained and easily transportable to remote sites to enable the acquisition of radiance data for almost the complete (4 pi) sky and ground-looking hemispheres in only 11 seconds was designed. The PARABOLA samples in 15 deg instantaneous field of view sectors in three narrow bandpass spectral channels simultaneously. Field measurement on a variety of earth surface cover types using a truck boom, a specially designed pickup truck mounting system, and a hot air balloon were studied. The PARABOLA instrument has potential for climatological and other studies which require characterization of the distribution of diffuse solar radiation within the sky hemisphere.

A sphere-scanning radiometer for rapid directional measurements of sky and ground radiance: The PARABOLA field instrument

NASA Astrophysics Data System (ADS)

Deering, D. W.; Leone, P.

1984-11-01

A unique field instrument, called the PARABOLA, a collapsable support boom, which is self contained and easily transportable to remote sites to enable the acquisition of radiance data for almost the complete (4 pi) sky and ground-looking hemispheres in only 11 seconds was designed. The PARABOLA samples in 15 deg instantaneous field of view sectors in three narrow bandpass spectral channels simultaneously. Field measurement on a variety of earth surface cover types using a truck boom, a specially designed pickup truck mounting system, and a hot air balloon were studied. The PARABOLA instrument has potential for climatological and other studies which require characterization of the distribution of diffuse solar radiation within the sky hemisphere.

Evaluation of alternative pedestrian control devices.

DOT National Transportation Integrated Search

2012-03-01

A literature review, field study of Rectangular Rapid Flashing Beacon (RRFB) installations in Oregon, and a static survey : on the sequencing of the Pedestrian Hybrid Beacon (PHB) were completed. : The field study conducted in this project was design...

A Biomes Field Trip.

ERIC Educational Resources Information Center

Leonard, William H.; And Others

1983-01-01

Describes a field trip designed to give students opportunities to experience relevant data leading to concepts in biogeography. Suggests that teachers (including college instructors) adapt the areas studied and procedures used to their own locations. Includes a suggested field trip handout. (JN)

Communities. Community Study Unit, Grade 1. Teacher Edition, Field Trip Guide for Teachers, and Student Book.

ERIC Educational Resources Information Center

Lee County School District, Ft. Myers, FL. Dept. of Environmental Education and Instructional Development Services.

This unit is designed to help first grade students understand the broad concept of community. The students experience a variety of in-class and field trip activities that will expose them to communities. The students observe and compare both natural and human-designed communities. Learning activities include pantomimes, listening activities,…

Systematic Field Study of NO(x) Emission Control Methods for Utility Boilers.

ERIC Educational Resources Information Center

Bartok, William; And Others

A utility boiler field test program was conducted. The objectives were to determine new or improved NO (x) emission factors by fossil fuel type and boiler design, and to assess the scope of applicability of combustion modification techniques for controlling NO (x) emissions from such installations. A statistically designed test program was…

U.S.-MEXICO BORDER PROGRAM ARIZONA BORDER STUDY--STANDARD OPERATING PROCEDURE FOR FIELD PERSONNEL TRAINING PLAN (UA-T-4.0)

EPA Science Inventory

The purpose of this SOP is to describe the training sequence of incoming field team members. The training procedure is designed to provide new team members with an overview of the goals, structure, and design of this research project and their role within it. This procedure was...

Effects of Cognitive Styles on an MSN Virtual Learning Companion System as an Adjunct to Classroom Instructions

ERIC Educational Resources Information Center

Hsieh, Sheng-Wen

2011-01-01

This study designed a chatbot system, Confucius, as a MSN virtual learning companion to examine how specific application design variables within educational software affect the learning process of subjects as defined by the cognitive continuum of field-dependent and field-independent learners. 104 college students participated in a 12 week…

NHEXAS PHASE I ARIZONA STUDY--STANDARD OPERATING PROCEDURE FOR FIELD PERSONNEL TRAINING PLAN (UA-T-4.0)

EPA Science Inventory

The purpose of this SOP is to describe the training sequence of incoming Field Team Members. The training procedure is designed to provide new team members with an overview of the goals, structure, and design of this research project and their role within it. This procedure was...

7 CFR 1737.30 - General.

Code of Federal Regulations, 2013 CFR

2013-01-01

... Studies-Area Coverage Survey and Loan Design § 1737.30 General. In support of a loan application, the... Coverage Survey) and (b) engineering studies to determine the system design that provides service most efficiently (the Loan Design). The RUS field representative confers with the borrower and its engineer to...

7 CFR 1737.30 - General.

Code of Federal Regulations, 2014 CFR

2014-01-01

... Studies-Area Coverage Survey and Loan Design § 1737.30 General. In support of a loan application, the... Coverage Survey) and (b) engineering studies to determine the system design that provides service most efficiently (the Loan Design). The RUS field representative confers with the borrower and its engineer to...

7 CFR 1737.30 - General.

Code of Federal Regulations, 2012 CFR

2012-01-01

... Studies-Area Coverage Survey and Loan Design § 1737.30 General. In support of a loan application, the... Coverage Survey) and (b) engineering studies to determine the system design that provides service most efficiently (the Loan Design). The RUS field representative confers with the borrower and its engineer to...

7 CFR 1737.30 - General.

Code of Federal Regulations, 2011 CFR

2011-01-01

... Studies-Area Coverage Survey and Loan Design § 1737.30 General. In support of a loan application, the... Coverage Survey) and (b) engineering studies to determine the system design that provides service most efficiently (the Loan Design). The RUS field representative confers with the borrower and its engineer to...

7 CFR 1737.30 - General.

Code of Federal Regulations, 2010 CFR

2010-01-01

... Studies-Area Coverage Survey and Loan Design § 1737.30 General. In support of a loan application, the... Coverage Survey) and (b) engineering studies to determine the system design that provides service most efficiently (the Loan Design). The RUS field representative confers with the borrower and its engineer to...

Design Fixation and Cooperative Learning in Elementary Engineering Design Project: A Case Study

ERIC Educational Resources Information Center

Luo, Yi

2015-01-01

This paper presents a case study examining 3rd, 4th and 5th graders' design fixation and cooperative learning in an engineering design project. A mixed methods instrument, the Cooperative Learning Observation Protocol (CLOP), was adapted to record frequency and class observation on cooperative learning engagement through detailed field notes.…

Robotic Follow-Up for Human Exploration

NASA Technical Reports Server (NTRS)

Fong, Terrence; Bualat, Maria; Deans, Matthew C.; Adams, Byron; Allan, Mark; Altobelli, Martha; Bouyssounouse, Xavier; Cohen, Tamar; Flueckiger, Lorenzo; Garber, Joshua;

Design consideration of high voltage Ga2O3 vertical Schottky barrier diode with field plate

NASA Astrophysics Data System (ADS)

Choi, J.-H.; Cho, C.-H.; Cha, H.-Y.

2018-06-01

Gallium oxide (Ga2O3) based vertical Schottky barrier diodes (SBDs) were designed for high voltage switching applications. Since p-type Ga2O3 epitaxy growth or p-type ion implantation technique has not been developed yet, a field plate structure was employed in this study to maximize the breakdown voltage by suppressing the electric field at the anode edge. TCAD simulation was used for the physical analysis of Ga2O3 SBDs from which it was found that careful attention must be paid to the insulator under the field plate. Due to the extremely high breakdown field property of Ga2O3, an insulator with both high permittivity and high breakdown field must be used for the field plate formation.

Education Longitudinal Study of 2002 (ELS:2002/12) Third Follow-up Field Test Report. Working Paper Series. NCES 2012-03

ERIC Educational Resources Information Center

Ingels, Steven J.; Pratt, Daniel J.; Jewell, Donna M.; Mattox, Tiffany; Dalton, Ben; Rosen, Jeffrey; Lauff, Erich; Hill, Jason

2012-01-01

This report describes the methodologies and results of the third follow-up Education Longitudinal Study of 2002 (ELS:2002/12) field test which was conducted in the summer of 2011. The field test report is divided into six chapters: (1) Introduction; (2) Field Test Survey Design and Preparation; (3) Data Collection Procedures and Results; (4) Field…

Wide Field X-Ray Telescope Mission Concept Study Results

NASA Technical Reports Server (NTRS)

Hopkins, R. C.; Thomas, H. D.; Fabisinski, L. L.; Baysinger, M.; Hornsby, L. S.; Maples, C. D.; Purlee, T. E.; Capizzo, P. D.; Percy, T. K.

2014-01-01

The Wide Field X-Ray Telescope (WFXT) is an astrophysics mission concept for detecting and studying extra-galactic x-ray sources, including active galactic nuclei and clusters of galaxies, in an effort to further understand cosmic evolution and structure. This Technical Memorandum details the results of a mission concept study completed by the Advanced Concepts Office at NASA Marshall Space Flight Center in 2012. The design team analyzed the mission and instrument requirements, and designed a spacecraft that enables the WFXT mission while using high heritage components. Design work included selecting components and sizing subsystems for power, avionics, guidance, navigation and control, propulsion, structures, command and data handling, communications, and thermal control.

Soil-cement study : final report.

DOT National Transportation Integrated Search

1973-11-01

This study consisted of an examination of the compressive strengths of soil-cement mixtures on 15 construction projects from the standpoint of design and actual achievement. The laboratory design test was examined closely along with the present field...

Optical System Design for Noncontact, Normal Incidence, THz Imaging of in vivo Human Cornea.

PubMed

Sung, Shijun; Dabironezare, Shahab; Llombart, Nuria; Selvin, Skyler; Bajwa, Neha; Chantra, Somporn; Nowroozi, Bryan; Garritano, James; Goell, Jacob; Li, Alex; Deng, Sophie X; Brown, Elliott; Grundfest, Warren S; Taylor, Zachary D

2018-01-01

Reflection mode Terahertz (THz) imaging of corneal tissue water content (CTWC) is a proposed method for early, accurate detection and study of corneal diseases. Despite promising results from ex vivo and in vivo cornea studies, interpretation of the reflectivity data is confounded by the contact between corneal tissue and dielectric windows used to flatten the imaging field. Herein, we present an optical design for non-contact THz imaging of cornea. A beam scanning methodology performs angular, normal incidence sweeps of a focused beam over the corneal surface while keeping the source, detector, and patient stationary. A quasioptical analysis method is developed to analyze the theoretical resolution and imaging field intensity profile. These results are compared to the electric field distribution computed with a physical optics analysis code. Imaging experiments validate the optical theories behind the design and suggest that quasioptical methods are sufficient for designing of THz corneal imaging systems. Successful imaging operations support the feasibility of non-contact in vivo imaging. We believe that this optical system design will enable the first, clinically relevant, in vivo exploration of CTWC using THz technology.

The Value of the Operational Principle in Instructional Design

ERIC Educational Resources Information Center

Gibbons, Andrew S.

2009-01-01

Formal design studies are increasing our insight into design processes, including those of instructional design. Lessons are being learned from other design fields, and new techniques and concepts can be imported as they are demonstrated effective. The purpose of this article is to introduce a design concept--the "operational principle"--for…

Ethnography by Design: On Goals and Mediating Artefacts

ERIC Educational Resources Information Center

Segelström, Fabian; Holmlid, Stefan

2015-01-01

Design ethnography is the appropriation of ethnography for the purposes of informing design. This paper investigates the effects of these appropriations, through a comparative study of how designers and anthropologists approach the same field site and by a review of new techniques introduced by designers to do ethnography. The techniques reviewed…

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)

Using a Field Trip Inventory to Determine If Listening to Elementary School Students' Conversations, While on a Zoo Field Trip, Enhances Preservice Teachers' Abilities to Plan Zoo Field Trips

NASA Astrophysics Data System (ADS)

Patrick, Patricia; Mathews, Cathy; Tunnicliffe, Sue Dale

2013-10-01

This study investigated whether listening to spontaneous conversations of elementary students and their teachers/chaperones, while they were visiting a zoo, affected preservice elementary teachers' conceptions about planning a field trip to the zoo. One hundred five preservice elementary teachers designed field trips prior to and after listening to students' conversations during a field trip to the zoo. In order to analyze the preservice teachers' field trip designs, we conducted a review of the literature on field trips to develop the field trip inventory (FTI). The FTI focussed on three major components of field trips: cognitive, procedural, and social. Cognitive components were subdivided into pre-visit, during-visit, and post-visit activities and problem-solving. Procedural components included information about the informal science education facility (the zoo) and the zoo staff and included advanced organizers. Social components on student groups, fun, control during the zoo visit, and control of student learning. The results of the investigation showed that (a) the dominant topic in conversations among elementary school groups at the zoo was management, (b) procedural components were mentioned least often, (c) preservice teachers described during-visit activities more often than any other characteristic central to field trip design, (d) seven of the nine characteristics listed in the FTI were noted more frequently in the preservice teachers' field trip designs after they listened to students' conversations at the zoo, and (e) preservice teachers thought that students were not learning and that planning was important.

Environmental and Water Quality Operational Studies. Environmental Guidelines for Dike Fields.

DTIC Science & Technology

1984-09-01

public release; distribution unlimited. I. DISTRIBUTION STATEMENT (of the abstract entered In Block 20, If different from Report) IS. SUPPLEMENTARY NOTES...necessary and identify by block number) Aquatic biology--Environmental aspects. (LC) Dikes (Engineering)--Design and construction--Environmental...w ad Idenwify by block number) ’The environmental guidelines for dike fields-contained within this report consist of environmental objectives, design

Family Interaction and Cognitive Style: Situation and Cross-Sex Effects.

ERIC Educational Resources Information Center

Dreyer, Albert S.

This study was designed to examine the family interaction differentiating the families of field dependent and field independent children. A total of 300 white, middle class, kindergarten children were tested with the Portable Rod and Frame Test and the Children.s Embedded Figures Test and were classified as field dependent or field independent…

Field Supervisor Perspectives on Evidence-Based Practice: Familiarity, Feasibility, and Implementation

ERIC Educational Resources Information Center

Heffernan, Kristin; Dauenhauer, Jason

2017-01-01

The Council on Social Work Education has designated field education as social work's signature pedagogy, putting field supervisors in a key role of preparing students as competent social workers. This study examined field supervisors' Evidence Based Practice (EBP) behaviors using a modified version of the Evidence-Based Practice Process Assessment…

The molecular shape and the field similarities as criteria to interpret SAR studies for fragment-based design of platinum(IV) anticancer agents. Correlation of physicochemical properties with cytotoxicity.

PubMed

Lorenzo, Julia; Montaña, Ángel M

2016-09-01

Molecular shape similarity and field similarity have been used to interpret, in a qualitative way, the structure-activity relationships in a selected series of platinum(IV) complexes with anticancer activity. MM and QM calculations have been used to estimate the electron density, electrostatic potential maps, partial charges, dipolar moments and other parameters to correlate the stereo-electronic properties with the differential biological activity of complexes. Extended Electron Distribution (XED) field similarity has been also evaluated for the free 1,4-diamino carrier ligands, in a fragment-based drug design approach, comparing Connolly solvent excluded surface, hydrophobicity field surface, Van der Waals field surface, nucleophilicity field surface, electrophilicity field surface and the extended electron-distribution maxima field points. A consistency has been found when comparing the stereo-electronic properties of the studied series of platinum(IV) complexes and/or the free ligands evaluated and their in vitro anticancer activity. Copyright © 2016 Elsevier Inc. All rights reserved.

WATER DISTRIBUTION SYSTEM ANALYSIS: FIELD STUDIES, MODELING AND MANAGEMENT

EPA Science Inventory

The user‘s guide entitled “Water Distribution System Analysis: Field Studies, Modeling and Management” is a reference guide for water utilities and an extensive summarization of information designed to provide drinking water utility personnel (and related consultants and research...

A Novel Method for Quantifying Helmeted Field of View of a Spacesuit - And What It Means for Constellation

NASA Technical Reports Server (NTRS)

McFarland, Shane M.

2010-01-01

Field of view has always been a design feature paramount to helmet design, and in particular spacesuit design, where the helmet must provide an adequate field of view for a large range of activities, environments, and body positions. Historically, suited field of view has been evaluated either qualitatively in parallel with design or quantitatively using various test methods and protocols. As such, oftentimes legacy suit field of view information is either ambiguous for lack of supporting data or contradictory to other field of view tests performed with different subjects and test methods. This paper serves to document a new field of view testing method that is more reliable and repeatable than its predecessors. It borrows heavily from standard ophthalmologic field of vision tests such as the Goldmann kinetic perimetry test, but is designed specifically for evaluating field of view of a spacesuit helmet. In this test, four suits utilizing three different helmet designs were tested for field of view. Not only do these tests provide more reliable field of view data for legacy and prototype helmet designs, they also provide insight into how helmet design impacts field of view and what this means for the Constellation Project spacesuit helmet, which must meet stringent field of view requirements that are more generous to the crewmember than legacy designs.

What Informs Practice and What Is Valued in Corporate Instructional Design? A Mixed Methods Study

ERIC Educational Resources Information Center

Thompson-Sellers, Ingrid N.

2012-01-01

This study used a two-phased explanatory mixed-methods design to explore in-depth what factors are perceived by Instructional Design and Technology (IDT) professionals as impacting instructional design practice, how these factors are valued in the field, and what differences in perspectives exist between IDT managers and non-managers. For phase 1…

Development of the CSNS Lambertson magnet with very low stray field

NASA Astrophysics Data System (ADS)

Wu, Yuwen; Kang, Wen; Chen, Yuan; Wu, Xi; Li, Shuai; Wang, Lei; Deng, Changdong; Li, Li; Zhou, Jianxin; Liu, Yiqin

2018-02-01

In this paper, the magnetic and mechanical design of Lambertson are studied, and then magnetic field measurements are introduced. The results show that the integral field uniformity and effective length meet the physical requirements. The shielding measures shield the stray field effectively and the stray field along the circulating beam orbit is at a very low level.

Satellite to study earth's magnetic field

NASA Technical Reports Server (NTRS)

1979-01-01

The Magnetic Field Satellite (Magsat) designed to measure the near earth magnetic field and crustal anomalies is briefly described. A scalar magnetometer to measure the magnitude of the earth's crustal magnetic field and a vector magnetometer to measure magnetic field direction as well as magnitude are included. The mission and its objectives are summarized along with the data collection and processing system.

Phased array-fed antenna configuration study

NASA Technical Reports Server (NTRS)

Crosswell, W. F.; Ball, D. E.; Taylor, R. C.

1983-01-01

The scope of this contract entails a configuration study for a phased array fed transmit antenna operating in the frequency band of 17.7 to 20.2 GHz. This initial contract provides a basis for understanding the design limitations and advantages of advanced phased array and cluster feeds (both utilizing intergral MMIC modules) illuminating folded reflector optics (both near field and focused types). Design parametric analyses are performed utilizing as constraints the objective secondary performance requirements of the Advanced Communications Technology Satellite (Table 1.0). The output of the study provides design information which serves as a data base for future active phased array fed antenna studies such as detailed designs required to support the development of a ground tested breadboard. In general, this study is significant because it provides the antenna community with an understanding of the basic principles which govern near field phased scanned feed effects on secondary reflector system performance. Although several articles have been written on analysis procedures and results for these systems, the authors of this report have observed phenomenon of near field antenna systems not previously documented. Because the physical justification for the exhibited performance is provided herein, the findings of this study add a new dimension to the available knowledge of the subject matter.

The NASA Exploration Design Team; Blueprint for a New Design Paradigm

NASA Technical Reports Server (NTRS)

Oberto, Robert E.; Nilsen, Erik; Cohen, Ron; Wheeler, Rebecca; DeFlorio, Paul

2005-01-01

NASA has chosen JPL to deliver a NASA-wide rapid-response real-time collaborative design team to perform rapid execution of program, system, mission, and technology trade studies. This team will draw on the expertise of all NASA centers and external partners necessary. The NASA Exploration Design Team (NEDT) will be led by NASA Headquarters, with field centers and partners added according to the needs of each study. Through real-time distributed collaboration we will effectively bring all NASA field centers directly inside Headquarters. JPL's Team X pioneered the technique of real time collaborative design 8 years ago. Since its inception, Team X has performed over 600 mission studies and has reduced per-study cost by a factor of 5 and per-study duration by a factor of 10 compared to conventional design processes. The Team X concept has spread to other NASA centers, industry, academia, and international partners. In this paper, we discuss the extension of the JPL Team X process to the NASA-wide collaborative design team. We discuss the architecture for such a process and elaborate on the implementation challenges of this process. We further discuss our current ideas on how to address these challenges.

DESIGN INFORMATION ON FINE PORE AERATION SYSTEMS

EPA Science Inventory

Field studies were conducted over several years at municipal wastewater treatment plants employing line pore diffused aeration systems. These studies were designed to produce reliable information on the performance and operational requirements of fine pore devices under process ...

Several examples where turbulence models fail in inlet flow field analysis

NASA Technical Reports Server (NTRS)

Anderson, Bernhard H.

1993-01-01

Computational uncertainties in turbulence modeling for three dimensional inlet flow fields include flows approaching separation, strength of secondary flow field, three dimensional flow predictions of vortex liftoff, and influence of vortex-boundary layer interactions; computational uncertainties in vortex generator modeling include representation of generator vorticity field and the relationship between generator and vorticity field. The objectives of the inlet flow field studies presented in this document are to advance the understanding, prediction, and control of intake distortion and to study the basic interactions that influence this design problem.

Expert System Approach For Generating And Evaluating Engine Design Alternatives

NASA Astrophysics Data System (ADS)

Shen, Stewart N. T.; Chew, Meng-Sang; Issa, Ghassan F.

1989-03-01

Artificial intelligence is becoming an increasingly important subject of study for computer scientists, engineering designers, as well as professionals in other fields. Even though AI technology is a relatively new discipline, many of its concepts have already found practical applications. Expert systems, in particular, have made significant contributions to technologies in such fields as business, medicine, engineering design, chemistry, and particle physics. This paper describes an expert system developed to aid the mechanical designer with the preliminary design of variable-stroke internal-combustion engines. The expert system accomplished its task by generating and evaluating a large number of design alternatives represented in the form of graphs. Through the application of structural and design rules directly to the graphs, optimal and near optimal preliminary design configurations of engines are deduced.

Cost-effective sampling of ¹³⁷Cs-derived net soil redistribution: part 1--estimating the spatial mean across scales of variation.

PubMed

Li, Y; Chappell, A; Nyamdavaa, B; Yu, H; Davaasuren, D; Zoljargal, K

2015-03-01

The (137)Cs technique for estimating net time-integrated soil redistribution is valuable for understanding the factors controlling soil redistribution by all processes. The literature on this technique is dominated by studies of individual fields and describes its typically time-consuming nature. We contend that the community making these studies has inappropriately assumed that many (137)Cs measurements are required and hence estimates of net soil redistribution can only be made at the field scale. Here, we support future studies of (137)Cs-derived net soil redistribution to apply their often limited resources across scales of variation (field, catchment, region etc.) without compromising the quality of the estimates at any scale. We describe a hybrid, design-based and model-based, stratified random sampling design with composites to estimate the sampling variance and a cost model for fieldwork and laboratory measurements. Geostatistical mapping of net (1954-2012) soil redistribution as a case study on the Chinese Loess Plateau is compared with estimates for several other sampling designs popular in the literature. We demonstrate the cost-effectiveness of the hybrid design for spatial estimation of net soil redistribution. To demonstrate the limitations of current sampling approaches to cut across scales of variation, we extrapolate our estimate of net soil redistribution across the region, show that for the same resources, estimates from many fields could have been provided and would elucidate the cause of differences within and between regional estimates. We recommend that future studies evaluate carefully the sampling design to consider the opportunity to investigate (137)Cs-derived net soil redistribution across scales of variation. Copyright © 2014 Elsevier Ltd. All rights reserved.

Optical system design with wide field of view and high resolution based on monocentric multi-scale construction

NASA Astrophysics Data System (ADS)

Wang, Fang; Wang, Hu; Xiao, Nan; Shen, Yang; Xue, Yaoke

2018-03-01

With the development of related technology gradually mature in the field of optoelectronic information, it is a great demand to design an optical system with high resolution and wide field of view(FOV). However, as it is illustrated in conventional Applied Optics, there is a contradiction between these two characteristics. Namely, the FOV and imaging resolution are limited by each other. Here, based on the study of typical wide-FOV optical system design, we propose the monocentric multi-scale system design method to solve this problem. Consisting of a concentric spherical lens and a series of micro-lens array, this system has effective improvement on its imaging quality. As an example, we designed a typical imaging system, which has a focal length of 35mm and a instantaneous field angle of 14.7", as well as the FOV set to be 120°. By analyzing the imaging quality, we demonstrate that in different FOV, all the values of MTF at 200lp/mm are higher than 0.4 when the sampling frequency of the Nyquist is 200lp/mm, which shows a good accordance with our design.

Pasadena City College SIGI Project Research Design. Pilot Study.

ERIC Educational Resources Information Center

Risser, John J.; Tulley, John E.

A pilot study evaluation of SIGI (System of Interactive Guidance and Information) at Pasadena City College in 1974-75 tested the effectiveness of an experimental research design for an expanded field test of the system the following year. (SIGI is a computer based career guidance program designed by Educational Testing Service to assist community…

Field methods to evaluate effects of pesticides on wildlife of the northwestern United States

USGS Publications Warehouse

Henny, C.J.

1987-01-01

Field .methods used to evaluate the impact of organochlorine and organophosphate pesticides on wildlife populations in the Pacific Northwest are reviewed. Five field studies, presented in a CASE HISTORY format, illustrate study designs .and thetypes of information collected. The pesticides investigated included DDT, heptachlor, endr1n, and famphur, and the species studied included the American kestrel (Falco sparverius), Canada goose (Branta canadensis}, black--crowned night-heron (Nycticorax nycticorac), and black-billed magpie (Pica pica). Wildlife biologists conducting field studies of pesticides encounter a variety of design and logistics problems. However, a number of procedures are now available to the researcher for field evaluations. The three principa1 types of insecticides (organochlorines (OC's), organophosphates (OP's) and carbamates (CB's) require different field approaches. In this paper, five field studies, conducted by my colleagues and me between 1974 and 1982, in the northwestern portion of the United States (Washington, Oregon, Idaho, and northern Nevada), are reviewed to illustrate procedures for evaluating the effects of these insecticides.on wildlife populations. Althought most OC pesticides were banned in the United States during the 1970's (.for review, see F1eming et al. 1983), we studied several OC applications, including the last major DDT spray project in 1974. Use of OP's and CB's increased during the 1970's and 1980s as the OC's were phased out.

Pilot study: evaluation of the use of the convergent interview technique in understanding the perception of surgical design and simulation.

PubMed

Logan, Heather; Wolfaardt, Johan; Boulanger, Pierre; Hodgetts, Bill; Seikaly, Hadi

2013-06-19

It is important to understand the perceived value of surgical design and simulation (SDS) amongst surgeons, as this will influence its implementation in clinical settings. The purpose of the present study was to examine the application of the convergent interview technique in the field of surgical design and simulation and evaluate whether the technique would uncover new perceptions of virtual surgical planning (VSP) and medical models not discovered by other qualitative case-based techniques. Five surgeons were asked to participate in the study. Each participant was interviewed following the convergent interview technique. After each interview, the interviewer interpreted the information by seeking agreements and disagreements among the interviewees in order to understand the key concepts in the field of SDS. Fifteen important issues were extracted from the convergent interviews. In general, the convergent interview was an effective technique in collecting information about the perception of clinicians. The study identified three areas where the technique could be improved upon for future studies in the SDS field.

Pilot study: evaluation of the use of the convergent interview technique in understanding the perception of surgical design and simulation

PubMed Central

2013-01-01

Background It is important to understand the perceived value of surgical design and simulation (SDS) amongst surgeons, as this will influence its implementation in clinical settings. The purpose of the present study was to examine the application of the convergent interview technique in the field of surgical design and simulation and evaluate whether the technique would uncover new perceptions of virtual surgical planning (VSP) and medical models not discovered by other qualitative case-based techniques. Methods Five surgeons were asked to participate in the study. Each participant was interviewed following the convergent interview technique. After each interview, the interviewer interpreted the information by seeking agreements and disagreements among the interviewees in order to understand the key concepts in the field of SDS. Results Fifteen important issues were extracted from the convergent interviews. Conclusion In general, the convergent interview was an effective technique in collecting information about the perception of clinicians. The study identified three areas where the technique could be improved upon for future studies in the SDS field. PMID:23782771

DESIGN OF A SURFACTANT REMEDIATION FIELD DEMONSTRATION BASED ON LABORATORY AND MODELINE STUDIES

EPA Science Inventory

Surfactant-enhanced subsurface remediation is being evaluated as an innovative technology for expediting ground-water remediation. This paper reports on laboratory and modeling studies conducted in preparation for a pilot-scale field test of surfactant-enhanced subsurface remedia...

MCE Field Study Project.

ERIC Educational Resources Information Center

Taber, Florence M.

The effectiveness of six microcomputer programs designed for the secondary to adult population to teach concepts associated with daily living skills (vocations, elementary budgeting, money management assessment, banking, and home safety) was studied. These programs were field tested in special education classrooms in three different school…

Destined to Design? How and Why Australian Women Choose to Study Industrial Design

ERIC Educational Resources Information Center

Lockhart, Cathy; Miller, Evonne

2016-01-01

Despite over three decades of legislation and initiatives designed to tackle the traditional gender divide in the science, technology and design fields, only a quarter of the registered architects in Australia are women. There are no statistics available for other design disciplines, with little known about why women choose design as a career path…

CSEM-Steel hybrid wiggler/undulator magnetic field studies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Halbach, K.; Hoyer, E.; Marks, S.

1985-06-01

Current design of permanent magnet wiggler/undulators use either pure charge sheet equivalent material (CSEM) or the CSEM-Steel hybrid configuration. Hybrid configurations offer higher field strength at small gaps, field distributions dominated by the pole surfaces and pole tuning. Nominal performance of the hybrid is generally predicted using a 2-D magnetic design code neglecting transverse geometry. Magnetic measurements are presented showing transverse configuration influence on performance, from a combination of models using CSEMs, REC (H/sub c/ = 9.2 KOe) and NdFe (H/sub c/ = 10.7 kOe), different pole widths and end configurations. Results show peak field improvement using NdFe in placemore » of REC in identical models, gap peak field decrease with pole width decrease (all results less than computed 2-D fields), transverse gap field distributions, and importance of CSEM material overhanging the poles in the transverse direction for highest gap fields. 3 refs., 6 figs.« less

Canted-Cosine-Theta Superconducting Accelerator Magnets for High Energy Physics and Ion Beam Cancer Therapy

NASA Astrophysics Data System (ADS)

Brouwer, Lucas Nathan

Advances in superconducting magnet technology have historically enabled the construction of new, higher energy hadron colliders. Looking forward to the needs of a potential future collider, a significant increase in magnet field and performance is required. Such a task requires an open mind to the investigation of new design concepts for high field magnets. Part I of this thesis will present an investigation of the Canted-Cosine-Theta (CCT) design for high field Nb3Sn magnets. New analytic and finite element methods for analysis of CCT magnets will be given, along with a discussion on optimization of the design for high field. The design, fabrication, and successful test of the 2.5 T NbTi dipole CCT1 will be presented as a proof-of-principle step towards a high field Nb3Sn magnet. Finally, the design and initial steps in the fabrication of the 16 T Nb3Sn dipole CCT2 will be described. Part II of this thesis will investigate the CCT concept extended to a curved magnet for use in an ion beam therapy gantry. The introduction of superconducting technology in this field shows promise to reduce the weight and cost of gantries, as well as open the door to new beam optics solutions with high energy acceptance. An analytic approach developed for modeling curved CCT magnets will be presented, followed by a design study of a superconducting magnet for a proton therapy gantry. Finally, a new magnet concept called the "Alternating Gradient CCT" (AG-CCT) will be introduced. This concept will be shown to be a practical magnet solution for achieving the alternating quadrupole fields desired for an achromatic gantry, allowing for the consideration of treatment with minimal field changes in the superconducting magnets. The primary motivation of this thesis is to share new developments for Canted-Cosine-Theta superconducting magnets, with the hope this design will improve technology for high energy physics and ion beam cancer therapy.

Content Analysis of Introductory Interior Design College Textbooks: A Study Revisited

ERIC Educational Resources Information Center

Temple, Julie A.; Potthoff, Joy K.

2013-01-01

Introductory interior design texts adopted by design educators present information relevant to both historical and contemporary issues in interior design. According to one author, they provide a "survey of the field of interior design as it now exists" (Pile, 2007). A comparison of the content of contemporary texts with those of more…

The Designer-by-Assignment in Practice: Instructional Design Thinking of Subject Matter Experts

ERIC Educational Resources Information Center

Pesce, Sandra V.

2012-01-01

Designers-by-assignment, or subject matter experts (SMEs) who are pressed into training service, have become common in the workplace. A review of more than 24 studies on expert and novice instructional designers, however, revealed that little is known about how designers-by-assignment think about design and make design decisions in the field. A…

(TUCSON) STUDY DESIGN AND PRELIMINARY EXPOSURE FINDINGS ASSOCIATED WITH THE DEARS

EPA Science Inventory

The Detroit Exposure and Aerosol Research Study (DEARS) is a three-year field monitoring study initiated in 2004 that is designed to measure exposure and describe exposure relationships for air toxics, PM components, PM from specific sources, and criteria pollutants. Detroit, Mic...

Periodontal Research: Basics and beyond - Part I (Defining the research problem, study design and levels of evidence).

PubMed

Avula, Haritha; Pandey, Ruchi; Bolla, Vijayalakshmi; Rao, Harika; Avula, Jaya Kumar

2013-09-01

Research in the field of periodontology has witnessed a tremendous upsurge in the last two decades unveiling newer innovations in techniques, methodologies, and material science. The recent focus in periodontal research is an evidence-based approach which offers a bridge from science to clinical practice. This three part review series intends to take a reader through a maze of periodontal research, unraveling and simplifying various issues in the design, conduct and interpretation of various study designs routinely used in the field of periodontal research. This understanding would facilitate a researcher with a focused and an enhanced vision toward formulating studies which can more efficiently translate sound scientific phenomena into clinically meaningful results.

Periodontal Research: Basics and beyond – Part I (Defining the research problem, study design and levels of evidence)

PubMed Central

Avula, Haritha; Pandey, Ruchi; Bolla, Vijayalakshmi; Rao, Harika; Avula, Jaya Kumar

2013-01-01

Research in the field of periodontology has witnessed a tremendous upsurge in the last two decades unveiling newer innovations in techniques, methodologies, and material science. The recent focus in periodontal research is an evidence-based approach which offers a bridge from science to clinical practice. This three part review series intends to take a reader through a maze of periodontal research, unraveling and simplifying various issues in the design, conduct and interpretation of various study designs routinely used in the field of periodontal research. This understanding would facilitate a researcher with a focused and an enhanced vision toward formulating studies which can more efficiently translate sound scientific phenomena into clinically meaningful results. PMID:24174746

Bridging the Field Trip Gap: Integrating Web-Based Video as a Teaching and Learning Partner in Interior Design Education

ERIC Educational Resources Information Center

Roehl, Amy

2013-01-01

This study utilizes web-based video as a strategy to transfer knowledge about the interior design industry in a format that interests the current generation of students. The model of instruction developed is based upon online video as an engaging, economical, and time-saving alternative to a field trip, guest speaker, or video teleconference.…

Analysis of Satellite Communications Antenna Patterns

NASA Technical Reports Server (NTRS)

Rahmat-Samii, Y.

1985-01-01

Computer program accurately and efficiently predicts far-field patterns of offset, or symmetric, parabolic reflector antennas. Antenna designer uses program to study effects of varying geometrical and electrical (RF) parameters of parabolic reflector and its feed system. Accurate predictions of far-field patterns help designer predict overall performance of antenna. These reflectors used extensively in modern communications satellites and in multiple-beam and low side-lobe antenna systems.

Field Test Report of the Self-Directed, Interpretive, and Creative Reading Elements of the Wisconsin Design for Reading Skill Development. Technical Report No. 330.

ERIC Educational Resources Information Center

Chester, Robert; And Others

This study of the self-directed, interpretive, and creative reading elements of the Wisconsin Design for Reading Skill Development was conducted to gather descriptive data about implementation strategies being developed and practiced by field test teachers and to gather evaluative information about the usability of various management and…

Evaluation of a Six Week Professional Education Curriculum Designed To Retrain Registered Psychiatric Nurses into the Field of Psychiatric Nursing.

ERIC Educational Resources Information Center

Safian-Rush, Donna

During the past few years, there has been a drastic shortage of registered nurses in the field of psychiatric mental health. An evaluation conducted on an internship curriculum designed to facilitate effective nursing care in the treatment of clients who exhibit emotional problems is presented with details on a study to attract and retain nurses…

Field experimental design comparisons to detect field effects associated with agronomic traits in Upland cotton

USDA-ARS?s Scientific Manuscript database

Field variation is one of the important factors that can have a significant impact on genetic data analysis. Ineffective control of field variation may result in an inflated residual variance and/or biased estimation of genetic variations and/or effects. In this study, we addressed this problem by m...

Construction and Application of a Terahertz Scanning Near-Field Microscope for Study of Correlated Electron Materials at Cryogenic Temperatures and Nanometer Length Scales

NASA Astrophysics Data System (ADS)

Stinson, Harry Theodore, III

This dissertation describes the design and construction of the world's first cryogenic apertureless near-field microscope designed for terahertz sources and detectors. I first provide motivation for the creation of this instrument in the context of spectroscopy of correlated electron materials, and background information on the two techniques that the instrument combines, scanning near-field optical microscopy and terahertz time-domain spectroscopy. I then detail key components of the instrument design, including proof-of-principle results obtained at room and cryogenic temperatures. Following this, I discuss an imaging experiment performed with this instrument on vanadium dioxide, an insulator-metal transition material, which sheds new light on the nature of the phase transition and provides support for a new model Hamiltonian for the system. Finally, I discuss a theoretical proposal for the study of cuprate superconductors using this instrument.

Key aspects of cost effective collector and solar field design

NASA Astrophysics Data System (ADS)

von Reeken, Finn; Nicodemo, Dario; Keck, Thomas; Weinrebe, Gerhard; Balz, Markus

2016-05-01

A study has been performed where different key parameters influencing solar field cost are varied. By using levelised cost of energy as figure of merit it is shown that parameters like GoToStow wind speed, heliostat stiffness or tower height should be adapted to respective site conditions from an economical point of view. The benchmark site Redstone (Northern Cape Province, South Africa) has been compared to an alternate site close to Phoenix (AZ, USA) regarding site conditions and their effect on cost-effective collector and solar field design.

Establishing a design procedure for buried steel-reinforced high-density polyethylene pipes : a field study.

DOT National Transportation Integrated Search

2015-11-01

Two field tests were conducted to investigate the field performance of steel-reinforced high-density polyethylene : (SRHDPE) pipes during installation and under traffic loading. One test site was located on E 1000 road in Lawrence, KS, which is : clo...

Comparison of Precision of Biomass Estimates in Regional Field Sample Surveys and Airborne LiDAR-Assisted Surveys in Hedmark County, Norway

NASA Technical Reports Server (NTRS)

Naesset, Erik; Gobakken, Terje; Bollandsas, Ole Martin; Gregoire, Timothy G.; Nelson, Ross; Stahl, Goeran

2013-01-01

Airborne scanning LiDAR (Light Detection and Ranging) has emerged as a promising tool to provide auxiliary data for sample surveys aiming at estimation of above-ground tree biomass (AGB), with potential applications in REDD forest monitoring. For larger geographical regions such as counties, states or nations, it is not feasible to collect airborne LiDAR data continuously ("wall-to-wall") over the entire area of interest. Two-stage cluster survey designs have therefore been demonstrated by which LiDAR data are collected along selected individual flight-lines treated as clusters and with ground plots sampled along these LiDAR swaths. Recently, analytical AGB estimators and associated variance estimators that quantify the sampling variability have been proposed. Empirical studies employing these estimators have shown a seemingly equal or even larger uncertainty of the AGB estimates obtained with extensive use of LiDAR data to support the estimation as compared to pure field-based estimates employing estimators appropriate under simple random sampling (SRS). However, comparison of uncertainty estimates under SRS and sophisticated two-stage designs is complicated by large differences in the designs and assumptions. In this study, probability-based principles to estimation and inference were followed. We assumed designs of a field sample and a LiDAR-assisted survey of Hedmark County (HC) (27,390 km2), Norway, considered to be more comparable than those assumed in previous studies. The field sample consisted of 659 systematically distributed National Forest Inventory (NFI) plots and the airborne scanning LiDAR data were collected along 53 parallel flight-lines flown over the NFI plots. We compared AGB estimates based on the field survey only assuming SRS against corresponding estimates assuming two-phase (double) sampling with LiDAR and employing model-assisted estimators. We also compared AGB estimates based on the field survey only assuming two-stage sampling (the NFI plots being grouped in clusters) against corresponding estimates assuming two-stage sampling with the LiDAR and employing model-assisted estimators. For each of the two comparisons, the standard errors of the AGB estimates were consistently lower for the LiDAR-assisted designs. The overall reduction of the standard errors in the LiDAR-assisted estimation was around 40-60% compared to the pure field survey. We conclude that the previously proposed two-stage model-assisted estimators are inappropriate for surveys with unequal lengths of the LiDAR flight-lines and new estimators are needed. Some options for design of LiDAR-assisted sample surveys under REDD are also discussed, which capitalize on the flexibility offered when the field survey is designed as an integrated part of the overall survey design as opposed to previous LiDAR-assisted sample surveys in the boreal and temperate zones which have been restricted by the current design of an existing NFI.

Conceptual design of a compact high gradient quadrupole magnet of varying strength using permanent magnets

NASA Astrophysics Data System (ADS)

Sinha, Gautam

2018-02-01

A concept is presented to design magnets using cylindrical-shaped permanent-magnet blocks, where various types of magnetic fields can be produced by either rotating or varying the size of the magnetic blocks within a given mechanical structure. A general method is introduced to calculate the 3D magnetic field produced by a set of permanent magnets. An analytical expression of the 2D field and the condition to generate various magnetic fields like dipole, quadrupole, and sextupole are derived. Using the 2D result as a starting point, a computer code is developed to get the optimum orientation of the magnets to obtain the user-specific target field profile over a given volume in 3D. Designs of two quadrupole magnets are presented, one using 12 and the other using 24 permanent-magnet blocks. Variation of the quadrupole strength is achieved using tuning coils of a suitable current density and specially designed end tubes. A new concept is introduced to reduce the integrated quadrupole field strength by inserting two hollow cylindrical tubes made of iron, one at each end. This will not affect the field gradient at the center but reduce the integrated field strength by shielding the magnetic field near the ends where the tubes are inserted. The advantages of this scheme are that it is easy to implement, the magnetic axis will not shift, and it will prevent interference with nearby devices. Around 40% integrated field variation is achieved using this method in the present example. To get a realistic estimation of the field quality, a complete 3D model using a nonlinear B -H curve is also studied using a finite-element-based computer code. An example to generate around an 80 T /m quadrupole field gradient is also presented.

Design Considerations and Experimental Verification of a Rail Brake Armature Based on Linear Induction Motor Technology

NASA Astrophysics Data System (ADS)

Sakamoto, Yasuaki; Kashiwagi, Takayuki; Hasegawa, Hitoshi; Sasakawa, Takashi; Fujii, Nobuo

This paper describes the design considerations and experimental verification of an LIM rail brake armature. In order to generate power and maximize the braking force density despite the limited area between the armature and the rail and the limited space available for installation, we studied a design method that is suitable for designing an LIM rail brake armature; we considered adoption of a ring winding structure. To examine the validity of the proposed design method, we developed a prototype ring winding armature for the rail brakes and examined its electromagnetic characteristics in a dynamic test system with roller rigs. By repeating various tests, we confirmed that unnecessary magnetic field components, which were expected to be present under high speed running condition or when a ring winding armature was used, were not present. Further, the necessary magnetic field component and braking force attained the desired values. These studies have helped us to develop a basic design method that is suitable for designing the LIM rail brake armatures.

The use of affective interaction design in car user interfaces.

PubMed

Gkouskos, Dimitrios; Chen, Fang

2012-01-01

Recent developments in the car industry have put Human Machine Interfaces under the spotlight. Developing gratifying human-car interactions has become one of the more prominent areas that car manufacturers want to invest in. However, concepts like emotional design remain foreign to the industry. In this study 12 experts on the field of automobile HMI design were interviewed in order to investigate their needs and opinions of emotional design. Results show that emotional design has yet to be introduced for this context of use. Designers need a tool customized for the intricacies of the car HMI field that can provide them with support and guidance so that they can create emotionally attractive experiences for drivers and passengers alike.

Foveated optics

NASA Astrophysics Data System (ADS)

Bryant, Kyle R.

2016-05-01

Foveated imaging can deliver two different resolutions on a single focal plane, which might inexpensively allow more capability for military systems. The following design study results provide starting examples, lessons learned, and helpful setup equations and pointers to aid the lens designer in any foveated lens design effort. Our goal is to put robust sensor in a small package with no moving parts, but still be able to perform some of the functions of a sensor in a moving gimbal. All of the elegant solutions are out (for various reasons). This study is an attempt to see if lens designs can solve this problem and realize some gains in performance versus cost for airborne sensors. We determined a series of design concepts to simultaneously deliver wide field of view and high foveal resolution without scanning or gimbals. Separate sensors for each field of view are easy and relatively inexpensive, but lead to bulky detectors and electronics. Folding and beam-combining of separate optical channels reduces sensor footprint, but induces image inversions and reduced transmission. Entirely common optics provide good resolution, but cannot provide a significant magnification increase in the foveal region. Offsetting the foveal region from the wide field center may not be physically realizable, but may be required for some applications. The design study revealed good general guidance for foveated optics designs with a cold stop. Key lessons learned involve managing distortion, telecentric imagers, matching image inversions and numerical apertures between channels, reimaging lenses, and creating clean resolution zone splits near internal focal planes.

A field evaluation of data link flight information services for general aviation pilots

DOT National Transportation Integrated Search

1997-02-01

This report documents a field study of Data Link Flight Information Services : (FIS) designed for use by general aviation (GA) pilots. The Data Link FIS : package that was evaluated in this study included the Traffic Information : Service (TIS), Text...

Engineering properties of resin modified pavement (RMP) for mechanistic design

NASA Astrophysics Data System (ADS)

Anderton, Gary Lee

1997-11-01

The research study described in this report focuses on determining the engineering properties of the resin modified pavement (RMP) material relating to pavement performance, and then developing a rational mechanistic design procedure to replace the current empirical design procedure. A detailed description of RMP is provided, including a review of the available literature on this relatively new pavement technology. Field evaluations of four existing and two new RMP project sites were made to assess critical failure modes and to obtain pavement samples for subsequent laboratory testing. Various engineering properties of laboratory-produced and field-recovered samples of RMP were measured and analyzed. The engineering properties evaluated included those relating to the material's stiffness, strength, thermal properties, and traffic-related properties. Comparisons of these data to typical values for asphalt concrete and portland cement concrete were made to relate the physical nature of RMP to more common pavement surfacing materials. A mechanistic design procedure was developed to determine appropriate thickness profiles of RMP, using stiffness and fatigue properties determined by this study. The design procedure is based on the U.S. Army Corps of Engineers layered elastic method for airfield flexible pavements. The WESPAVE computer program was used to demonstrate the new design procedure for a hypothetical airfield apron design. The results of the study indicated that RMP is a relatively stiff, viscoelastic pavement surfacing material with many of its strength and stiffness properties falling between those of typical asphalt concrete and portland cement concrete. The RMP's thermal and traffic-related properties indicated favorable field performance. The layered elastic design approach appeared to be a reasonable and practical method for RMP mechanistic pavement design, and this design procedure was recommended for future use and development.

Universities' Intermediary Role in the "Design for Sustainability" Field

ERIC Educational Resources Information Center

Küçüksayraç, Elif; Wever, Renee; Brezet, Han

2017-01-01

Purpose: This paper aims to investigate the intermediary role of universities in spreading design for sustainability into industry. Design/methodology/approach: Three case studies were undertaken on Delft University of Technology, Design for Sustainability Program from The Netherlands; a center on sustainable consumption and production; and Prof.…

Predictive and postdictive analysis of forage yield trials

USDA-ARS?s Scientific Manuscript database

Classical experimental design theory, the predominant treatment in most textbooks, promotes the use of blocking designs for control of spatial variability in field studies and other situations in which there is significant variation among heterogeneity among experimental units. Many blocking design...

Design, Research, and Design Research: Synergies and Contradictions

ERIC Educational Resources Information Center

Nelson, Wayne A.

2013-01-01

Notions of design, research, and design research in the field of educational technology are quite different from conceptualizations held by other design fields. Examining the ways that research is conducted and used in educational technology in comparison to other design fields can provide novel insights into how research and design practice can…

( DETROIT, MI ) STUDY DESIGN AND PRELIMINARY EXPOSURE FINDINGS ASSOCIATED WITH THE DEARS

EPA Science Inventory

The Detroit Exposure and Aerosol Research Study (DEARS) is a three-year field monitoring study initiated in 2004 that is designed to measure exposure and describe exposure relationships for air toxics, PM components, PM from specific sources, and criteria pollutants. Detroit, Mic...

Rehabilitation of jointed Portland cement concrete pavements : SPS-6--initial evaluation and analysis

DOT National Transportation Integrated Search

2005-10-01

The Specific Pavement Studies 6 (SPS-6) experiment, "Rehabilitation of Jointed Portland Cement Concrete Pavements," was designed as a controlled field experiment that focuses on the study of specific rehabilitation design features of jointed plain co...

Selection of nontarget arthropod taxa for field research on transgenic insecticidal crops: using empirical data and statistical power.

PubMed

Prasifka, J R; Hellmich, R L; Dively, G P; Higgins, L S; Dixon, P M; Duan, J J

2008-02-01

One of the possible adverse effects of transgenic insecticidal crops is the unintended decline in the abundance of nontarget arthropods. Field trials designed to evaluate potential nontarget effects can be more complex than expected because decisions to conduct field trials and the selection of taxa to include are not always guided by the results of laboratory tests. Also, recent studies emphasize the potential for indirect effects (adverse impacts to nontarget arthropods without feeding directly on plant tissues), which are difficult to predict because of interactions among nontarget arthropods, target pests, and transgenic crops. As a consequence, field studies may attempt to monitor expansive lists of arthropod taxa, making the design of such broad studies more difficult and reducing the likelihood of detecting any negative effects that might be present. To improve the taxonomic focus and statistical rigor of future studies, existing field data and corresponding power analysis may provide useful guidance. Analysis of control data from several nontarget field trials using repeated-measures designs suggests that while detection of small effects may require considerable increases in replication, there are taxa from different ecological roles that are sampled effectively using standard methods. The use of statistical power to guide selection of taxa for nontarget trials reflects scientists' inability to predict the complex interactions among arthropod taxa, particularly when laboratory trials fail to provide guidance on which groups are more likely to be affected. However, scientists still may exercise judgment, including taxa that are not included in or supported by power analyses.

Planning and setting objectives in field studies: Chapter 2

USGS Publications Warehouse

Fisher, Robert N.; Dodd, C. Kenneth

2016-01-01

This chapter enumerates the steps required in designing and planning field studies on the ecology and conservation of reptiles, as these involve a high level of uncertainty and risk. To this end, the chapter differentiates between goals (descriptions of what one intends to accomplish) and objectives (the measurable steps required to achieve the established goals). Thus, meeting a specific goal may require many objectives. It may not be possible to define some of them until certain experiments have been conducted; often evaluations of sampling protocols are needed to increase certainty in the biological results. And if sampling locations are fixed and sampling events are repeated over time, then both study-specific covariates and sampling-specific covariates should exist. Additionally, other critical design considerations for field study include obtaining permits, as well as researching ethics and biosecurity issues.

The School for Field Studies Centre for Coastal Studies: A Case Study of Sustainable Development Education in Mexico

ERIC Educational Resources Information Center

Farrell, T. A.; Ollervides, F.

2005-01-01

Purpose: To present the School for Field Studies-Centre for Coastal Studies (SFS-CCS) study abroad Mexico program, and consider its relative success as a sustainable development education program. Design/methodology/approach: The SFS-CCS academic model and results of its implementation are presented. Program success is discussed by applying…

Adaptive optics for MOSAIC: design and performance of the wide(st)-field AO system for the E-ELT

NASA Astrophysics Data System (ADS)

Morris, Tim; Basden, Alastair; Buey, Tristan; Chemla, Fanny; Conan, Jean-Marc; Fitzsimons, Ewan; Fusco, Thierry; Gendron, Eric; Hammer, Francois; Jagourel, Pascal; Morel, Carine; Myers, Richard; Neichel, Benoit; Petit, Cyril; Rodrigues, Myriam; Rousset, Gérard

2016-07-01

MOSAIC is the proposed multiple-object spectrograph for the E-ELT that will utilise the widest possible field of view provided by the telescope. In terms of adaptive optics, there are two distinct operating modes required to meet the top-level science requirements. The MOSAIC High Multiplex Mode (HMM) requires either seeing-limited or GLAO correction within a 0.6 (NIR) and 0.9 (VIS) arcsecond sub-fields over the widest possible field for a few hundred objects. To achieve seeing limited operation whilst maintaining the maximum unvignetted field of view for scientific observation will require recreating some of the functionality present in the Pre-Focal Station relating to control of the E-ELT active optics. MOSAIC High Definition Mode Control (HDM) requires a 25% Ensquared Energy (EE) within 150mas in the H-band element for approximately 10 targets distributed across the full E-ELT field, implying the use of Multiple Object AO (MOAO). Initial studies have shown that to meet the EE requirements whilst maintaining high-sky coverage will require the combination of wavefront signals from both high-order NGS and LGS to provide a tomographic estimate for the correction to be applied to the open-loop MOAO DMs. In this paper we present the current MOSAIC AO design and provide the first performance estimates for the baseline instrument design. We then report on the various trade-offs that will be investigated throughout the course of the Phase A study, such as the requirement to mix NGS and LGS signals tomographically. Finally, we discuss how these will impact the AO architecture, the MOSAIC design and ultimately the scientific performance of this wide-field workhorse instrument at the E-ELT.

Identifying Unique Ethical Challenges of Indigenous Field-Workers: A Commentary on Alexander and Richman's "Ethical Dilemmas in Evaluations Using Indigenous Research Workers"

ERIC Educational Resources Information Center

Smith, Nick L.

2008-01-01

In contrast with nonindigenous workers, to what extent do unique ethical problems arise when indigenous field-workers participate in field studies? Three aspects of study design and operation are considered: data integrity issues, risk issues, and protection issues. Although many of the data quality issues that arise with the use of indigenous…

[A study of magnetic shielding design for a magnetic resonance imaging linac system].

PubMed

Zhang, Zheshun; Chen, Wenjing; Qiu, Yang; Zhu, Jianming

2017-12-01

One of the main technical challenges when integrating magnetic resonance imaging (MRI) systems with medical linear accelerator is the strong interference of fringe magnetic fields from the MRI system with the electron beams of linear accelerator, making the linear accelerator not to work properly. In order to minimize the interference of magnetic fields, a magnetic shielding cylinder with an open structure made of high permeability materials is designed. ANSYS Maxwell was used to simulate Helmholtz coil which generate uniform magnetic field instead of the fringe magnetic fields which affect accelerator gun. The parameters of shielding tube, such as permeability, radius, length, side thickness, bottom thickness and fringe magnetic fields strength are simulated, and the data is processed by MATLAB to compare the shielding performance. This article gives out a list of magnetic shielding effectiveness with different side thickness and bottom thickness under the optimal radius and length, which showes that this design can meet the shielding requirement for the MRI-linear accelerator system.

Extra high speed modified Lundell alternator parameters and open/short-circuit characteristics from global 3D-FE magnetic field solutions

NASA Astrophysics Data System (ADS)

Wang, R.; Demerdash, N. A.

1992-06-01

The combined magnetic vector potential - magnetic scalar potential method of computation of 3D magnetic fields by finite elements, introduced in a companion paper, is used for global 3D field analysis and machine performance computations under open-circuit and short-circuit conditions for an example 14.3 kVA modified Lundell alternator, whose magnetic field is of intrinsic 3D nature. The computed voltages and currents under these machine test conditions were verified and found to be in very good agreement with corresponding test data. Results of use of this modelling and computation method in the study of a design alteration example, in which the stator stack length of the example alternator is stretched in order to increase voltage and volt-ampere rating, are given here. These results demonstrate the inadequacy of conventional 2D-based design concepts and the imperative of use of this type of 3D magnetic field modelling in the design and investigation of such machines.

Extra high speed modified Lundell alternator parameters and open/short-circuit characteristics from global 3D-FE magnetic field solutions

NASA Technical Reports Server (NTRS)

Wang, R.; Demerdash, N. A.

1992-01-01

The combined magnetic vector potential - magnetic scalar potential method of computation of 3D magnetic fields by finite elements, introduced in a companion paper, is used for global 3D field analysis and machine performance computations under open-circuit and short-circuit conditions for an example 14.3 kVA modified Lundell alternator, whose magnetic field is of intrinsic 3D nature. The computed voltages and currents under these machine test conditions were verified and found to be in very good agreement with corresponding test data. Results of use of this modelling and computation method in the study of a design alteration example, in which the stator stack length of the example alternator is stretched in order to increase voltage and volt-ampere rating, are given here. These results demonstrate the inadequacy of conventional 2D-based design concepts and the imperative of use of this type of 3D magnetic field modelling in the design and investigation of such machines.

Wide-field ultraviolet imager for astronomical transient studies

NASA Astrophysics Data System (ADS)

Mathew, Joice; Ambily, S.; Prakash, Ajin; Sarpotdar, Mayuresh; Nirmal, K.; G. Sreejith, A.; Safonova, Margarita; Murthy, Jayant; Brosch, Noah

2018-04-01

Though the ultraviolet (UV) domain plays a vital role in the studies of astronomical transient events, the UV time-domain sky remains largely unexplored. We have designed a wide-field UV imager that can be flown on a range of available platforms, such as high-altitude balloons, CubeSats, and larger space missions. The major scientific goals are the variability of astronomical sources, detection of transients such as supernovae, novae, tidal disruption events, and characterizing active galactic nuclei variability. The instrument has a 80 mm aperture with a circular field of view of 10.8 degrees, an angular resolution of ˜22 arcsec, and a 240 - 390 nm spectral observation window. The detector for the instrument is a Microchannel Plate (MCP)-based image intensifier with both photon counting and integration capabilities. An FPGA-based detector readout mechanism and real time data processing have been implemented. The imager is designed in such a way that its lightweight and compact nature are well fitted for the CubeSat dimensions. Here we present various design and developmental aspects of this UV wide-field transient explorer.

Tolerance Studies of the Mu2e Solenoid System

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lopes, M. L.; Ambrosio, G.; Buehler, M.

2014-01-01

The muon-to-electron conversion experiment at Fermilab is designed to explore charged lepton flavor violation. It is composed of three large superconducting solenoids, namely, the production solenoid, the transport solenoid, and the detector solenoid. Each subsystem has a set of field requirements. Tolerance sensitivity studies of the magnet system were performed with the objective of demonstrating that the present magnet design meets all the field requirements. Systematic and random errors were considered on the position and alignment of the coils. The study helps to identify the critical sources of errors and which are translated to coil manufacturing and mechanical support tolerances.

The Utilization of Edge-of-Field Monitoring of Agricultural Runoff in Addressing Nonpoint Source Pollution

USDA-ARS?s Scientific Manuscript database

While basin-scale studies and modeling are important tools in relating land uses to water quality concerns, edge-of-field monitoring (EOFM) provides the necessary resolution to spatially target, design, and evaluate in-field conservation practices for reducing nutrient and sediment loading from agri...

Avionics Instrument Systems Specialist (AFSC 32551).

ERIC Educational Resources Information Center

Miller, Lawrence B.; Crowcroft, Robert A.

This six-volume student text is designed for use by Air Force personnel enrolled in a self-study extension course for avionics instrument systems specialists. Covered in the individual volumes are career field familiarization (career field progression and training, security, occupational safety and health, and career field reference material);…

Supervisor Attachment, Supervisory Working Alliance, and Affect in Social Work Field Instruction

ERIC Educational Resources Information Center

Bennett, Susanne; Mohr, Jonathan; Deal, Kathleen Holtz; Hwang, Jeongha

2013-01-01

Objective: This study focused on interrelationships among supervisor attachment, supervisory working alliance, and supervision-related affect, plus the moderating effect of a field instructor training. Method: The researchers employed a pretest-posttest follow-up design of 100 randomly assigned field instructors and 64 students in two…

Researching Design Practices and Design Cognition: Contexts, Experiences and Pedagogical Knowledge-in-Pieces

ERIC Educational Resources Information Center

Kali, Yael; Goodyear, Peter; Markauskaite, Lina

2011-01-01

If research and development in the field of learning design is to have a serious and sustained impact on education, then technological innovation needs to be accompanied--and probably guided--by good empirical studies of the design practices and design thinking of those who develop these innovations. This article synthesises two related lines of…

Prototype Imaging Spectrograph for Coronagraphic Exoplanet Studies (PISCES) for WFIRST/AFTA

NASA Technical Reports Server (NTRS)

Gong, Qian; McElwain, Michael; Greeley, Bradford; Grammer, Bryan; Marx, Catherine; Memarsadeghi, Nargess; Hilton, George; Perrin, Marshall; Sayson, Llop; Domingo, Jorge;

Field study of communication and workload in police helicopters - Implications for AI cockpit design

NASA Technical Reports Server (NTRS)

Linde, Charlotte; Shively, Robert J.

1988-01-01

This paper reports on the work performed by civilian helicopter crews, using audio and video recordings and a variety of workload measures (heart rate and subjective ratings) obtained in a field study of public service helicopter missions. The number and frequency of communications provided a significant source of workload. This is relevant to the design of automated cockpit systems, since many designs presuppose the use of voice I/O systems. Fluency of communications (including pauses, hesitation markers, repetitions, and false starts) furnished an early indication of the effects of fatigue. Three workload measures were correlated to identify high workload segments of flight, and to suggest alternate task allocations between crew members.

Establishing a design procedure for buried steel-reinforced high-density polyethylene pipes : a field study, [technical summary].

DOT National Transportation Integrated Search

2015-11-01

Several national standards and specification have been developed for design, installation, : and materials for precast concrete pipe, corrugated metal pipe, and HDPE pipes. However, : no national accepted installation standard or design method is ava...

Using a Field Trip Inventory to Determine If Listening to Elementary School Students' Conversations, While on a Zoo Field Trip, Enhances Preservice Teachers' Abilities to Plan Zoo Field Trips

ERIC Educational Resources Information Center

Patrick, Patricia; Mathews, Cathy; Tunnicliffe, Sue Dale

2013-01-01

This study investigated whether listening to spontaneous conversations of elementary students and their teachers/chaperones, while they were visiting a zoo, affected preservice elementary teachers' conceptions about planning a field trip to the zoo. One hundred five preservice elementary teachers designed field trips prior to and after…

Laboratory study - laboratory testing of bridge deck mixes

DOT National Transportation Integrated Search

2003-03-01

The purpose of this investigation was to develop bridge deck mixes that will improve field performance and minimize cracking potential compared to MoDOT's current (B-2) bridge deck mix design. The mix designs developed in this study were tested and c...

Single-Case Design Research: Building the Evidence-Base in the Field of Education of Deaf and Hard of Hearing Students

ERIC Educational Resources Information Center

Cannon, Joanna E.; Guardino, Caroline; Antia, Shirin D.; Luckner, John L.

2015-01-01

The field of education of deaf and hard of hearing (DHH) students has a paucity of evidence-based practices (EBPs) to guide instruction. The authors discussed how the research methodology of single-case design (SCD) can be used to build EBPs through direct and systematic replication of studies. An overview of SCD research methods is presented,…

MECHANICAL DRAFTING AND DESIGN TECHNOLOGY, JOB DESCRIPTIONS AND SUGGESTED TECHNIQUES FOR DETERMINING COURSES OF STUDY IN VOCATIONAL EDUCATION PROGRAMS.

ERIC Educational Resources Information Center

PETERSON, CLARENCE E.

THIS IS THE FIRST OF A SERIES DESIGNED TO PROVIDE AID TO STATES IN ORGANIZING AND OPERATING PROGRAMS UNDER TITLE VIII OF THE NATIONAL DEFENSE EDUCATION ACT, PUBLIC LAW 85-864. IT FURNISHES--(1) GENERAL INFORMATION ABOUT A TECHNOLOGY OR BROAD FIELD OF WORK, (2) COMPOSITE JOB DESCRIPTIONS OF REPRESENTATIVE OCCUPATIONS IN THAT FIELD OF WORK, (3) A…

Advances in Residential Design Related to the Influence of Geomagnetism.

PubMed

Glaria, Francisco; Arnedo, Israel; Sánchez-Ostiz, Ana

2018-02-23

Since the origin of the Modern Movement, there has been a basic commitment to improving housing conditions and the well-being of occupants, especially given the prediction that 2/3 of humanity will reside in cities by 2050. Moreover, a compact model of the city with tall buildings and urban densification at this scale will be generated. Continuous constructive and technological advances have developed solid foundations on safety, energy efficiency, habitability, and sustainability in housing design. However, studies on improving the quality of life in these areas continue to be a challenge for architects and engineers. This paper seeks to contribute health-related information to the study of residential design, specifically the influence of the geomagnetic field on its occupants. After compiling information on the effects of geomagnetic fields from different medical studies over 23 years, a case study of a 16-story high-rise building is presented, with the goal of proposing architectural design recommendations for long-term occupation in the same place. The purpose of the present work is three-fold: first, to characterize the geomagnetic field variability of buildings; second, to identify the causes and possible related mechanisms; and third, to define architectural criteria on the arrangement of uses and constructive elements for housing.

Advances in Residential Design Related to the Influence of Geomagnetism

PubMed Central

Arnedo, Israel; Sánchez-Ostiz, Ana

2018-01-01

Since the origin of the Modern Movement, there has been a basic commitment to improving housing conditions and the well-being of occupants, especially given the prediction that 2/3 of humanity will reside in cities by 2050. Moreover, a compact model of the city with tall buildings and urban densification at this scale will be generated. Continuous constructive and technological advances have developed solid foundations on safety, energy efficiency, habitability, and sustainability in housing design. However, studies on improving the quality of life in these areas continue to be a challenge for architects and engineers. This paper seeks to contribute health-related information to the study of residential design, specifically the influence of the geomagnetic field on its occupants. After compiling information on the effects of geomagnetic fields from different medical studies over 23 years, a case study of a 16-story high-rise building is presented, with the goal of proposing architectural design recommendations for long-term occupation in the same place. The purpose of the present work is three-fold: first, to characterize the geomagnetic field variability of buildings; second, to identify the causes and possible related mechanisms; and third, to define architectural criteria on the arrangement of uses and constructive elements for housing. PMID:29473902

Diagnostic techniques for measurement of aerodynamic noise in free field and reverberant environment of wind tunnels

NASA Technical Reports Server (NTRS)

El-Sum, H. M. A.; Mawardi, O. K.

1973-01-01

Techniques for studying aerodynamic noise generating mechanisms without disturbing the flow in a free field, and in the reverberation environment of the ARC wind tunnel were investigated along with the design and testing of an acoustic antenna with an electronic steering control. The acoustic characteristics of turbojet as a noise source, detection of direct sound from a source in a reverberant background, optical diagnostic methods, and the design characteristics of a high directivity acoustic antenna. Recommendations for further studies are included.

Stratigraphic traps 3

DOE Office of Scientific and Technical Information (OSTI.GOV)

Foster, N.H.; Beaumont, E.A.

1992-01-01

This book reports on the Treatise of Petroleum Geology was conceived during a discussion held at the annual AAPG meeting in 1984 in San Antonio, Texas. With input form the Advisory Board of the Treatise of Petroleum Geology, the authors designed this set of publications to represent, to the degree possible, the cutting edge in petroleum exploration knowledge and application: the Reprint Series to provide useful and important published literature; the Atlas to comprise a collection of detailed field studies that illustrate the many ways oil and gas are trapped and to serve as a guide to the petroleum geologymore » of basins where these fields are found; and the Handbook as a professional explorationist's guide to the latest knowledge in the various areas of petroleum geology and related disciplines. The treatise Atlas is part of AAPG's long tradition of publishing field studies. Notable AAPG field study complications include Structure of Typical American Fields, published in 1929 and edited by Sidney Powers; and Memoir 30, Giant Fields of 1968-1978, published in 1981 and edited by Michel T. Halbouty. The Treatise Atlas continues that tradition but introduces a format designed for easier access to data.« less

Towards non-conventional methods of designing register-based epidemiological studies: An application to pediatric research.

PubMed

Gong, Tong; Brew, Bronwyn; Sjölander, Arvid; Almqvist, Catarina

2017-07-01

Various epidemiological designs have been applied to investigate the causes and consequences of fetal growth restriction in register-based observational studies. This review seeks to provide an overview of several conventional designs, including cohort, case-control and more recently applied non-conventional designs such as family-based designs. We also discuss some practical points regarding the application and interpretation of family-based designs. Definitions of each design, the study population, the exposure and the outcome measures are briefly summarised. Examples of study designs are taken from the field of low birth-weight research for illustrative purposes. Also examined are relative advantages and disadvantages of each design in terms of assumptions, potential selection and information bias, confounding and generalisability. Kinship data linkage, statistical models and result interpretation are discussed specific to family-based designs. When all information is retrieved from registers, there is no evident preference of the case-control design over the cohort design to estimate odds ratios. All conventional designs included in the review are prone to bias, particularly due to residual confounding. Family-based designs are able to reduce such bias and strengthen causal inference. In the field of low birth-weight research, family-based designs have been able to confirm a negative association not confounded by genetic or shared environmental factors between low birth weight and the risk of asthma. We conclude that there is a broader need for family-based design in observational research as evidenced by the meaningful contributions to the understanding of the potential causal association between low birth weight and subsequent outcomes.

Hospital graduate social work field work programs: a study in New York City.

PubMed

Showers, N

1990-02-01

Twenty-seven hospital field work programs in New York City were studied. Questionnaires were administered to program coordinators and 238 graduate social work students participating in study programs. High degrees of program structural complexity and variation were found, indicating a state of art well beyond that described in the general field work literature. High rates of student satisfaction with learning, field instructors, programs, and the overall field work experience found suggest that the complexity of study programs may be more effective than traditional field work models. Statistically nonsignificant study findings indicate areas in which hospital social work departments may develop field work programs consistent with shifting organizational needs, without undue risk to educational effectiveness. Statistically significant findings suggest areas in which inflexibility in program design may be more beneficial in the diagnostic related groups era.

Exploring Design Elements for Online STEM Courses: Active Learning, Engagement & Assessment Design

ERIC Educational Resources Information Center

Chen, Baiyun; Bastedo, Kathleen; Howard, Wendy

2018-01-01

The purpose of this study was to examine effective design elements for online courses in the science, technology, engineering, and mathematics (STEM) fields at a large four-year public university in southeastern United States. Our research questions addressed the influence of online design elements on students' perception of learning and learning…

Developing Elementary Math and Science Process Skills Through Engineering Design Instruction

NASA Astrophysics Data System (ADS)

Strong, Matthew G.

This paper examines how elementary students can develop math and science process skills through an engineering design approach to instruction. The performance and development of individual process skills overall and by gender were also examined. The study, preceded by a pilot, took place in a grade four extracurricular engineering design program in a public, suburban school district. Students worked in pairs and small groups to design and construct airplane models from styrofoam, paper clips, and toothpicks. The development and performance of process skills were assessed through a student survey of learning gains, an engineering design packet rubric (student work), observation field notes, and focus group notes. The results indicate that students can significantly develop process skills, that female students may develop process skills through engineering design better than male students, and that engineering design is most helpful for developing the measuring, suggesting improvements, and observing process skills. The study suggests that a more regular engineering design program or curriculum could be beneficial for students' math and science abilities both in this school and for the elementary field as a whole.

An improved design method of a tuned mass damper for an in-service footbridge

NASA Astrophysics Data System (ADS)

Shi, Weixing; Wang, Liangkun; Lu, Zheng

2018-03-01

Tuned mass damper (TMD) has a wide range of applications in the vibration control of footbridges. However, the traditional engineering design method may lead to a mistuned TMD. In this paper, an improved TMD design method based on the model updating is proposed. Firstly, the original finite element model (FEM) is studied and the natural characteristics of the in-service or newly built footbridge is identified by field test, and then the original FEM is updated. TMD is designed according to the new updated FEM, and it is optimized according to the simulation on vibration control effects. Finally, the installation and field measurement of TMD are carried out. The improved design method can be applied to both in-service and newly built footbridges. This paper illustrates the improved design method with an engineering example. The frequency identification results of field test and original FEM show that there is a relatively large difference between them. The TMD designed according to the updated FEM has better vibration control effect than the TMD designed according to the original FEM. The site test results show that TMD has good effect on controlling human-induced vibrations.

Molecular dynamics, flexible docking, virtual screening, ADMET predictions, and molecular interaction field studies to design novel potential MAO-B inhibitors.

PubMed

Braun, Glaucia H; Jorge, Daniel M M; Ramos, Henrique P; Alves, Raquel M; da Silva, Vinicius B; Giuliatti, Silvana; Sampaio, Suley Vilela; Taft, Carlton A; Silva, Carlos H T P

2008-02-01

Monoamine oxidase is a flavoenzyme bound to the mitochondrial outer membranes of the cells, which is responsible for the oxidative deamination of neurotransmitter and dietary amines. It has two distinct isozymic forms, designated MAO-A and MAO-B, each displaying different substrate and inhibitor specificities. They are the well-known targets for antidepressant, Parkinson's disease, and neuroprotective drugs. Elucidation of the x-ray crystallographic structure of MAO-B has opened the way for the molecular modeling studies. In this work we have used molecular modeling, density functional theory with correlation, virtual screening, flexible docking, molecular dynamics, ADMET predictions, and molecular interaction field studies in order to design new molecules with potential higher selectivity and enzymatic inhibitory activity over MAO-B.

Incidental Becomes Visible: A Comparison of School- and Community-Based Field Experience Narratives

ERIC Educational Resources Information Center

Holder, K. C.; Downey, Jayne A.

2008-01-01

The purpose of this study was to describe and compare student learning documented using written field experience summary narratives and occurring in community-based or school-based locations. Utilizing a hybrid portraiture--instrumental case study design, two researchers selected participants from undergraduate educational psychology courses using…

Genetic analysis without replications: Model evaluation and application in spring wheat

USDA-ARS?s Scientific Manuscript database

Genetic data collected from plant breeding and genetic studies may not be replicated in field designs even though field variation is present. In this study, we addressed this problem using spring wheat (Triticum eastivum L.) trial data collected from two locations. There were no intra-location repl...

Characterizing The Microbial Community In A TCE DNAPL Site: SABRE Column And Field Studies

EPA Science Inventory

The SABRE (Source Area BioREmediation) project is evaluating accelerated anaerobic bioremediation of chlorinated solvents in areas of high concentration, such as DNAPL source areas. In support of a field scale pilot test, column studies were conducted to design the system and ob...

Design Methodology for Magnetic Field-Based Soft Tri-Axis Tactile Sensors.

PubMed

Wang, Hongbo; de Boer, Greg; Kow, Junwai; Alazmani, Ali; Ghajari, Mazdak; Hewson, Robert; Culmer, Peter

2016-08-24

Tactile sensors are essential if robots are to safely interact with the external world and to dexterously manipulate objects. Current tactile sensors have limitations restricting their use, notably being too fragile or having limited performance. Magnetic field-based soft tactile sensors offer a potential improvement, being durable, low cost, accurate and high bandwidth, but they are relatively undeveloped because of the complexities involved in design and calibration. This paper presents a general design methodology for magnetic field-based three-axis soft tactile sensors, enabling researchers to easily develop specific tactile sensors for a variety of applications. All aspects (design, fabrication, calibration and evaluation) of the development of tri-axis soft tactile sensors are presented and discussed. A moving least square approach is used to decouple and convert the magnetic field signal to force output to eliminate non-linearity and cross-talk effects. A case study of a tactile sensor prototype, MagOne, was developed. This achieved a resolution of 1.42 mN in normal force measurement (0.71 mN in shear force), good output repeatability and has a maximum hysteresis error of 3.4%. These results outperform comparable sensors reported previously, highlighting the efficacy of our methodology for sensor design.

Design Methodology for Magnetic Field-Based Soft Tri-Axis Tactile Sensors

PubMed Central

Wang, Hongbo; de Boer, Greg; Kow, Junwai; Alazmani, Ali; Ghajari, Mazdak; Hewson, Robert; Culmer, Peter

2016-01-01

Tactile sensors are essential if robots are to safely interact with the external world and to dexterously manipulate objects. Current tactile sensors have limitations restricting their use, notably being too fragile or having limited performance. Magnetic field-based soft tactile sensors offer a potential improvement, being durable, low cost, accurate and high bandwidth, but they are relatively undeveloped because of the complexities involved in design and calibration. This paper presents a general design methodology for magnetic field-based three-axis soft tactile sensors, enabling researchers to easily develop specific tactile sensors for a variety of applications. All aspects (design, fabrication, calibration and evaluation) of the development of tri-axis soft tactile sensors are presented and discussed. A moving least square approach is used to decouple and convert the magnetic field signal to force output to eliminate non-linearity and cross-talk effects. A case study of a tactile sensor prototype, MagOne, was developed. This achieved a resolution of 1.42 mN in normal force measurement (0.71 mN in shear force), good output repeatability and has a maximum hysteresis error of 3.4%. These results outperform comparable sensors reported previously, highlighting the efficacy of our methodology for sensor design. PMID:27563908

Structural concept studies for a horizontal cylindrical lunar habitat and a lunar guyed tower

NASA Technical Reports Server (NTRS)

Yin, Paul K.

1990-01-01

A conceptual structural design of a horizontal cylindrical lunar habitat is presented. The design includes the interior floor framing, the exterior support structure, the foundation mat, and the radiation shielding. Particular attention was given on its efficiency in shipping and field erection, and on selection of structural materials. Presented also is a conceptual design of a 2000-foot lunar guyed tower. A special field erection scheme is implemented in the design. In order to analyze the over-all column buckling of the mast, where its axial compression includes its own body weight, a simple numerical procedure is formulated in a form ready for coding in FORTRAN. Selection of structural materials, effect of temperature variations, dynamic response of the tower to moonquake, and guy anchoring system are discussed. Proposed field erection concepts for the habitat and for the guyed tower are described.

Magnetic-Nozzle Studies for Fusion Propulsion Applications: Gigawatt Plasma Source Operation and Magnetic Nozzle Analysis

NASA Technical Reports Server (NTRS)

Gilland, James H.; Mikekkides, Ioannis; Mikellides, Pavlos; Gregorek, Gerald; Marriott, Darin

2004-01-01

This project has been a multiyear effort to assess the feasibility of a key process inherent to virtually all fusion propulsion concepts: the expansion of a fusion-grade plasma through a diverging magnetic field. Current fusion energy research touches on this process only indirectly through studies of plasma divertors designed to remove the fusion products from a reactor. This project was aimed at directly addressing propulsion system issues, without the expense of constructing a fusion reactor. Instead, the program designed, constructed, and operated a facility suitable for simulating fusion reactor grade edge plasmas, and to examine their expansion in an expanding magnetic nozzle. The approach was to create and accelerate a dense (up to l0(exp 20)/m) plasma, stagnate it in a converging magnetic field to convert kinetic energy to thermal energy, and examine the subsequent expansion of the hot (100's eV) plasma in a subsequent magnetic nozzle. Throughout the project, there has been a parallel effort between theoretical and numerical design and modelling of the experiment and the experiment itself. In particular, the MACH2 code was used to design and predict the performance of the magnetoplasmadynamic (MPD) plasma accelerator, and to design and predict the design and expected behavior for the magnetic field coils that could be added later. Progress to date includes the theoretical accelerator design and construction, development of the power and vacuum systems to accommodate the powers and mass flow rates of interest to out research, operation of the accelerator and comparison to theoretical predictions, and computational analysis of future magnetic field coils and the expected performance of an integrated source-nozzle experiment.

A survey of snake-inspired robot designs.

PubMed

Hopkins, James K; Spranklin, Brent W; Gupta, Satyandra K

2009-06-01

Body undulation used by snakes and the physical architecture of a snake body may offer significant benefits over typical legged or wheeled locomotion designs in certain types of scenarios. A large number of research groups have developed snake-inspired robots to exploit these benefits. The purpose of this review is to report different types of snake-inspired robot designs and categorize them based on their main characteristics. For each category, we discuss their relative advantages and disadvantages. This review will assist in familiarizing a newcomer to the field with the existing designs and their distinguishing features. We hope that by studying existing robots, future designers will be able to create new designs by adopting features from successful robots. The review also summarizes the design challenges associated with the further advancement of the field and deploying snake-inspired robots in practice.

Pulsed magnetic field generation suited for low-field unilateral nuclear magnetic resonance systems

NASA Astrophysics Data System (ADS)

Gaunkar, Neelam Prabhu; Selvaraj, Jayaprakash; Theh, Wei-Shen; Weber, Robert; Mina, Mani

2018-05-01

Pulsed magnetic fields can be used to provide instantaneous localized magnetic field variations. In presence of static fields, pulsed field variations are often used to apply torques and in-effect to measure behavior of magnetic moments in different states. In this work, the design and experimental performance of a pulsed magnetic field generator suited for low static field nuclear magnetic resonance (NMR) applications is presented. One of the challenges of low bias field NMR measurements is low signal to noise ratio due to the comparable nature of the bias field and the pulsed field. Therefore, a circuit is designed to apply pulsed currents through an inductive load, leading to generation of pulsed magnetic fields which can temporarily overpower the effect of the bias field on magnetic moments. The designed circuit will be tuned to operate at the precession frequency of 1H (protons) placed in a bias field produced by permanent magnets. The designed circuit parameters may be tuned to operate under different bias conditions. Therefore, low field NMR measurements can be performed for different bias fields. Circuit simulations were used to determine design parameters, corresponding experimental measurements will be presented in this work.

Construction of a solenoid used on a magnetized plasma experiment

DOE PAGES

Klein, S. R.; Manuel, M. J. -E.; Pollock, B. B.; ...

2014-10-30

Creating magnetized jets in the laboratory is relevant to studying young stellar objects, but generating these types of plasmas within the laboratory setting has proven to be challenging. Here, we present the construction of a solenoid designed to produce an axial magnetic field with strengths in the gap of up to 5 T. This novel design was a compact 75 mm × 63 mm × 88 mm, allowing it to be placed in the Titan target chamber. As a result, it was robust, surviving over 50 discharges producing fields ≲ 5 T, reaching a peak magnetic field of 12.5 T.

Qualitative Research and Educational Leadership: Essential Dynamics to Consider When Designing and Conducting Studies

ERIC Educational Resources Information Center

Brooks, Jeffrey S.; Normore, Anthony H.

2015-01-01

Purpose: The purpose of this paper is to highlight issues relayed to appropriate design and conduct of qualitative studies in educational leadership. Design/Methodology/Approach: The paper is a conceptual/logical argument that centers around the notion that while scholars in the field have at times paid attention to such dynamics, it is important…

Designing a Field Experience Tracking System in the Area of Special Education

ERIC Educational Resources Information Center

He, Wu; Watson, Silvana

2014-01-01

Purpose: To improve the quality of field experience, support field experience cooperation and streamline field experience management, the purpose of this paper is to describe the experience in using Activity Theory to design and develop a web-based field experience tracking system for a special education program. Design/methodology/approach: The…

Design principles for high–pressure force fields: Aqueous TMAO solutions from ambient to kilobar pressures

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hölzl, Christoph; Horinek, Dominik, E-mail: dominik.horinek@ur.de; Kibies, Patrick

Accurate force fields are one of the major pillars on which successful molecular dynamics simulations of complex biomolecular processes rest. They have been optimized for ambient conditions, whereas high-pressure simulations become increasingly important in pressure perturbation studies, using pressure as an independent thermodynamic variable. Here, we explore the design of non-polarizable force fields tailored to work well in the realm of kilobar pressures – while avoiding complete reparameterization. Our key is to first compute the pressure-induced electronic and structural response of a solute by combining an integral equation approach to include pressure effects on solvent structure with a quantum-chemical treatmentmore » of the solute within the embedded cluster reference interaction site model (EC-RISM) framework. Next, the solute’s response to compression is taken into account by introducing pressure-dependence into selected parameters of a well-established force field. In our proof-of-principle study, the full machinery is applied to N,N,N-trimethylamine-N-oxide (TMAO) in water being a potent osmolyte that counteracts pressure denaturation. EC-RISM theory is shown to describe well the charge redistribution upon compression of TMAO(aq) to 10 kbar, which is then embodied in force field molecular dynamics by pressure-dependent partial charges. The performance of the high pressure force field is assessed by comparing to experimental and ab initio molecular dynamics data. Beyond its broad usefulness for designing non-polarizable force fields for extreme thermodynamic conditions, a good description of the pressure-response of solutions is highly recommended when constructing and validating polarizable force fields.« less

Design principles for high-pressure force fields: Aqueous TMAO solutions from ambient to kilobar pressures.

PubMed

Hölzl, Christoph; Kibies, Patrick; Imoto, Sho; Frach, Roland; Suladze, Saba; Winter, Roland; Marx, Dominik; Horinek, Dominik; Kast, Stefan M

2016-04-14

Accurate force fields are one of the major pillars on which successful molecular dynamics simulations of complex biomolecular processes rest. They have been optimized for ambient conditions, whereas high-pressure simulations become increasingly important in pressure perturbation studies, using pressure as an independent thermodynamic variable. Here, we explore the design of non-polarizable force fields tailored to work well in the realm of kilobar pressures--while avoiding complete reparameterization. Our key is to first compute the pressure-induced electronic and structural response of a solute by combining an integral equation approach to include pressure effects on solvent structure with a quantum-chemical treatment of the solute within the embedded cluster reference interaction site model (EC-RISM) framework. Next, the solute's response to compression is taken into account by introducing pressure-dependence into selected parameters of a well-established force field. In our proof-of-principle study, the full machinery is applied to N,N,N-trimethylamine-N-oxide (TMAO) in water being a potent osmolyte that counteracts pressure denaturation. EC-RISM theory is shown to describe well the charge redistribution upon compression of TMAO(aq) to 10 kbar, which is then embodied in force field molecular dynamics by pressure-dependent partial charges. The performance of the high pressure force field is assessed by comparing to experimental and ab initio molecular dynamics data. Beyond its broad usefulness for designing non-polarizable force fields for extreme thermodynamic conditions, a good description of the pressure-response of solutions is highly recommended when constructing and validating polarizable force fields.

GeoJourney: A Field-Based, Interdisciplinary Approach to Teaching Geology, Native American Cultures, and Environmental Studies

ERIC Educational Resources Information Center

Elkins, Joe; Elkins, Nichole M. L.; Hemmings, Sarah N. J.

2008-01-01

GeoJourney is an interdisciplinary field trip in geology, Native American studies, and environmental studies designed for introductory-level undergraduates. The program travels 23,345 kilometers by van to national parks, industrial sites, museums, and Indian reservations in 24 of the United States. During the day, students carry out hands-on…

Development of interactive hypermedia software for high school biology: A research and development study

NASA Astrophysics Data System (ADS)

Alturki, Uthman T.

The goal of this research was to research, design, and develop a hypertext program for students who study biology. The Ecology Hypertext Program was developed using Research and Development (R&D) methodology. The purpose of this study was to place the final "product", a CD-ROM for learning biology concepts, in the hands of teachers and students to help them in learning and teaching process. The product was created through a cycle of literature review, needs assessment, development, and a cycle of field tests and revisions. I applied the ten steps of R&D process suggested by Borg and Gall (1989) which, consisted of: (1) Literature review, (2) Needs assessment, (3) Planning, (4) Develop preliminary product, (5) Preliminary field-testing, (6) Preliminary revision, (7) Main field-testing, (8) Main revision, (9) Final field-testing, and (10) Final product revision. The literature review and needs assessment provided a support and foundation for designing the preliminary product---the Ecology Hypertext Program. Participants in the needs assessment joined a focus group discussion. They were a group of graduate students in education who suggested the importance for designing this product. For the preliminary field test, the participants were a group of high school students studying biology. They were the potential user of the product. They reviewed the preliminary product and then filled out a questionnaire. Their feedback and suggestions were used to develop and improve the product in a step called preliminary revision. The second round of field tasting was the main field test in which the participants joined a focus group discussion. They were the same group who participated in needs assessment task. They reviewed the revised product and then provided ideas and suggestions to improve the product. Their feedback were categorized and implemented to develop the product as in the main revision task. Finally, a group of science teachers participated in this study by reviewing the product and then filling out the questionnaire. Their suggestions were used to conduct the final step in R&D methodology, the final product revision. The primary result of this study was the Ecology Hypertext Program. It considered a small attempt to give students an opportunity to learn through an interactive hypertext program. In addition, using the R&D methodology was an ideal procedure for designing and developing new educational products and material.

Introducing Field-Based Geologic Research Using Soil Geomorphology

ERIC Educational Resources Information Center

Eppes, Martha Cary

2009-01-01

A field-based study of soils and the factors that influence their development is a strong, broad introduction to geologic concepts and research. A course blueprint is detailed where students design and complete a semester-long field-based soil geomorphology project. Students are first taught basic soil concepts and to describe soil, sediment and…

Utilizing Field-Based Instruction as an Effective Teaching Strategy

ERIC Educational Resources Information Center

Kozar, Joy M.; Marcketti, Sara B.

2008-01-01

The purpose of this study was to examine the effectiveness of field-based instruction on student learning outcomes. Researchers in the past have noted the importance of engaging students on a deeper level through the use of active course designs. To investigate the outcomes of active learning, two field assignments created for two separate…

The Impact of an Inquiry-Based Geoscience Field Course on Pre-Service Teachers

ERIC Educational Resources Information Center

Nugent, Gwen; Toland, Michael D.; Levy, Richard; Kunz, Gina; Harwood, David; Green, Denise; Kitts, Kathy

2012-01-01

The purpose of this quasi-experimental study was to determine the effects of a field-based, inquiry-focused course on pre-service teachers' geoscience content knowledge, attitude toward science, confidence in teaching science, and inquiry understanding and skills. The field-based course was designed to provide students with opportunities to…

Optimizing the Design of Preprinted Orders for Ambulatory Chemotherapy: Combining Oncology, Human Factors, and Graphic Design

PubMed Central

Jeon, Jennifer; White, Rachel E.; Hunt, Richard G.; Cassano-Piché, Andrea L.; Easty, Anthony C.

2012-01-01

Purpose: To establish a set of guidelines for developing ambulatory chemotherapy preprinted orders. Methods: Multiple methods were used to develop the preprinted order guidelines. These included (A) a comprehensive literature review and an environmental scan; (B) analyses of field study observations and incident reports; (C) critical review of evidence from the literature and the field study observation analyses; (D) review of the draft guidelines by a clinical advisory group; and (E) collaboration with graphic designers to develop sample preprinted orders, refine the design guidelines, and format the resulting content. Results: The Guidelines for Developing Ambulatory Chemotherapy Preprinted Orders, which consist of guidance on the design process, content, and graphic design elements of ambulatory chemotherapy preprinted orders, have been established. Conclusion: Health care is a safety critical, dynamic, and complex sociotechnical system. Identifying safety risks in such a system and effectively addressing them often require the expertise of multiple disciplines. This study illustrates how human factors professionals, clinicians, and designers can leverage each other's expertise to uncover commonly overlooked patient safety hazards and to provide health care professionals with innovative, practical, and user-centered tools to minimize those hazards. PMID:23077436

Optimizing the design of preprinted orders for ambulatory chemotherapy: combining oncology, human factors, and graphic design.

PubMed

Jeon, Jennifer; White, Rachel E; Hunt, Richard G; Cassano-Piché, Andrea L; Easty, Anthony C

2012-03-01

To establish a set of guidelines for developing ambulatory chemotherapy preprinted orders. Multiple methods were used to develop the preprinted order guidelines. These included (A) a comprehensive literature review and an environmental scan; (B) analyses of field study observations and incident reports; (C) critical review of evidence from the literature and the field study observation analyses; (D) review of the draft guidelines by a clinical advisory group; and (E) collaboration with graphic designers to develop sample preprinted orders, refine the design guidelines, and format the resulting content. The Guidelines for Developing Ambulatory Chemotherapy Preprinted Orders, which consist of guidance on the design process, content, and graphic design elements of ambulatory chemotherapy preprinted orders, have been established. Health care is a safety critical, dynamic, and complex sociotechnical system. Identifying safety risks in such a system and effectively addressing them often require the expertise of multiple disciplines. This study illustrates how human factors professionals, clinicians, and designers can leverage each other's expertise to uncover commonly overlooked patient safety hazards and to provide health care professionals with innovative, practical, and user-centered tools to minimize those hazards.

The Study on Human-Computer Interaction Design Based on the Users’ Subconscious Behavior

NASA Astrophysics Data System (ADS)

Li, Lingyuan

2017-09-01

Human-computer interaction is human-centered. An excellent interaction design should focus on the study of user experience, which greatly comes from the consistence between design and human behavioral habit. However, users’ behavioral habits often result from subconsciousness. Therefore, it is smart to utilize users’ subconscious behavior to achieve design's intention and maximize the value of products’ functions, which gradually becomes a new trend in this field.

Field-based optimal-design of an electric motor: a new sensitivity formulation

NASA Astrophysics Data System (ADS)

Barba, Paolo Di; Mognaschi, Maria Evelina; Lowther, David Alister; Wiak, Sławomir

2017-12-01

In this paper, a new approach to robust optimal design is proposed. The idea is to consider the sensitivity by means of two auxiliary criteria A and D, related to the magnitude and isotropy of the sensitivity, respectively. The optimal design of a switched-reluctance motor is considered as a case study: since the case study exhibits two design criteria, the relevant Pareto front is approximated by means of evolutionary computing.

Bifunctional metamaterials with simultaneous and independent manipulation of thermal and electric fields.

PubMed

Lan, Chuwen; Bi, Ke; Fu, Xiaojian; Li, Bo; Zhou, Ji

2016-10-03

Metamaterials offer a powerful way to manipulate a variety of physical fields ranging from wave fields (electromagnetic field, acoustic field, elastic wave, etc.), static fields (static magnetic field, static electric field) to diffusive fields (thermal field, diffusive mass). However, the relevant reports and studies are usually limited to a single physical field or functionality. In this study, we proposed and experimentally demonstrated a bifunctional metamaterial which could manipulate thermal and electric fields simultaneously and independently. Specifically, a composite with independently controllable thermal and electric conductivity was introduced, on the basis of which a bifunctional device capable of shielding thermal flux and concentrating electric current simultaneously was designed, fabricated and characterized. This work provides an encouraging example of metamaterials transcending their natural limitations, which offers a promising future in building a broad platform for the manipulation of multi-physics fields.

The Opinions of Masters Students about the Learning Program in the Field of Teaching Turkish to Foreigners

ERIC Educational Resources Information Center

Kilinç, Hasan Huseyin

2015-01-01

The purpose of this study is to determine the opinions of Master students about the learning program in the field of teaching Turkish to foreigners. In the study, case study design which is one of the qualitative research methods was used. The population of the study consists of students studying in the Master program with thesis of Teaching…

Designing Ready to Deliver Units of Learning: A Case Study

ERIC Educational Resources Information Center

Maina, Marcello

2009-01-01

The field of instructional design and technology has always evolved and grown, translating new knowledge in the learning and cognitive sciences into instructional principles, increasingly incorporating technological innovations into the design of educational solutions, and adapting to social changes (Reiser, 2007; Tennyson, 2005). The "learning…

Design standards for experimental and field studies to evaluate diagnostic accuracy of tests for infectious diseases in aquatic animals.

PubMed

Laurin, E; Thakur, K K; Gardner, I A; Hick, P; Moody, N J G; Crane, M S J; Ernst, I

2018-05-01

Design and reporting quality of diagnostic accuracy studies (DAS) are important metrics for assessing utility of tests used in animal and human health. Following standards for designing DAS will assist in appropriate test selection for specific testing purposes and minimize the risk of reporting biased sensitivity and specificity estimates. To examine the benefits of recommending standards, design information from published DAS literature was assessed for 10 finfish, seven mollusc, nine crustacean and two amphibian diseases listed in the 2017 OIE Manual of Diagnostic Tests for Aquatic Animals. Of the 56 DAS identified, 41 were based on field testing, eight on experimental challenge studies and seven on both. Also, we adapted human and terrestrial-animal standards and guidelines for DAS structure for use in aquatic animal diagnostic research. Through this process, we identified and addressed important metrics for consideration at the design phase: study purpose, targeted disease state, selection of appropriate samples and specimens, laboratory analytical methods, statistical methods and data interpretation. These recommended design standards for DAS are presented as a checklist including risk-of-failure points and actions to mitigate bias at each critical step. Adherence to standards when designing DAS will also facilitate future systematic review and meta-analyses of DAS research literature. © 2018 John Wiley & Sons Ltd.

Space telescope optical telescope assembly/scientific instruments. Phase B: Preliminary design and program definition study. Volume 2A(3): Astrometry

NASA Technical Reports Server (NTRS)

1976-01-01

Wide field measurements, namely, measurements of relative angular separations between stars over a relatively wide field for parallax and proper motion determinations, were made with the third fine guidance sensor. Narrow field measurements, i.e., double star measurements, are accomplished primarily with the area photometer or faint object camera at f/96. The wavelength range required can be met by the fine guidance sensor which has a spectral coverage from 3000 to 7500 A. The field of view of the fine guidance sensor also exceeds that required for the wide field astrometric instrument. Requirements require a filter wheel for the wide field astrometer, and so one was incorporated into the design of the fine guidance sensor. The filter wheel probably would contain two neutral density filters to extend the dynamic range of the sensor and three spectral filters for narrowing effective double star magnitude difference.

Topology optimization based design of unilateral NMR for generating a remote homogeneous field.

PubMed

Wang, Qi; Gao, Renjing; Liu, Shutian

2017-06-01

This paper presents a topology optimization based design method for the design of unilateral nuclear magnetic resonance (NMR), with which a remote homogeneous field can be obtained. The topology optimization is actualized by seeking out the optimal layout of ferromagnetic materials within a given design domain. The design objective is defined as generating a sensitive magnetic field with optimal homogeneity and maximal field strength within a required region of interest (ROI). The sensitivity of the objective function with respect to the design variables is derived and the method for solving the optimization problem is presented. A design example is provided to illustrate the utility of the design method, specifically the ability to improve the quality of the magnetic field over the required ROI by determining the optimal structural topology for the ferromagnetic poles. Both in simulations and experiments, the sensitive region of the magnetic field achieves about 2 times larger than that of the reference design, validating validates the feasibility of the design method. Copyright © 2017. Published by Elsevier Inc.

High Voltage Design Considerations for the Electrostatic Septum for the Mu2e Beam Resonant

DOE Office of Scientific and Technical Information (OSTI.GOV)

Alvarez, Matthew L.; Jensen, C.; Morris, D.

aTwo electrostatic septa (ESS) are being designed for the slow extraction of 8GeV proton beam for the Mu2e experiment at Fermilab. Special attention is given to the high voltage components that affect the performance of the septa. The components under consideration are the high voltage (HV) feedthrough, cathode standoff (CS), and clearing electrode ceramic standoffs (CECS). Previous experience with similar HV systems at Fermilab was used to define the evaluation criteria of the design of the high voltage components. Using electric field simulation software, high E-field intensities on the components and integrated field strength along the surface of the dielectricmore » material were minimized. Here we discuss the limitations found and improvements made based on those studies.« less

Important considerations for designing and reporting epidemiologic and clinical studies in dental traumatology.

PubMed

Andersson, Lars; Andreasen, Jens O

2011-08-01

The purpose of this article is to suggest important considerations for epidemiologic and clinical studies in the field of dental traumatology. The article is based on the authors' experiences from research in this field and editorial board work for the scientific journal Dental Traumatology. Examples are given of issues where development is important. The importance of planning ahead of the study and consulting with experts in other fields is emphasized. © 2011 John Wiley & Sons A/S.

Commentary on "Studying eyewitness investigations in the field": a look forward.

PubMed

Steblay, Nancy Kay

2008-02-01

Schacter et al. (2007, this issue) address the controversy surrounding an Illinois pilot project that attempted to compare sequential versus simultaneous police lineup formats. The statement by these experts will guide the design and execution of future field lineup experiments. This commentary discusses three aspects of field studies that pose challenges as lineup experiments are interpreted: the imprecise meaning of the dependent measure (eyewitness decisions), the limitations of single studies, and the necessity to devise public policy from incomplete knowledge. A combination of laboratory and field information provides the means to determine best practices in eyewitness identification procedures.

Aberrations for Grazing Incidence Optics

NASA Technical Reports Server (NTRS)

Saha, Timo T.

2008-01-01

Large number of grazing incidence telescope configurations have been designed and studied. Wolte1 telescopes are commonly used in astronomical applications. Wolter telescopes consist of a paraboloidal primary mirror and a hyperboloidal or an ellipsoidal secondary mirror. There are 8 possible combinations of Wolter telescopes. Out of these possible designs only type 1 and type 2 telescopes are widely used. Type 1 telescope is typically used for x-ray applications and type 2 telescopes are used for EUV applications. Wolter-Schwarzshild (WS) telescopes offer improved image quality over a small field of view. The WS designs are stigmatic and free of third order coma and, therefore, the PSF is significantly better over a small field of view. Typically the image is more symmetric about its centroid. As for the Wolter telescopes there are 8 possible combinations of WS telescopes. These designs have not been widely used because the surface equations are complex parametric equations complicating the analysis and typically the resolution requirements are too low to take full advantage of the WS designs. There are several other design options. Most notable are wide field x-ray telescope designs. Polynomial designs were originally suggested by Burrows4 and hyperboloid-hyperboloid designs for solar physics applications were designed by Harvey5. No general aberration theory exists for grazing incidence telescopes that would cover all the design options. Several authors have studied the aberrations of grazing incidence telescopes. A comprehensive theory of Wolter type 1 and 2 telescopes has been developed. Later this theory was expanded to include all possible combinations of grazing incidence and also normal incidence paraboloid-hyperboloid and paraboloid-ellipsoid telescopes. In this article the aberration theory of Wolter type telescopes is briefly reviewed.

Low-cost modular array-field designs for flat-panel and concentrator photovoltaic systems

NASA Astrophysics Data System (ADS)

Post, H. N.; Carmichael, D. C.; Alexander, G.; Castle, J. A.

1982-09-01

Described are the design and development of low-cost, modular array fields for flat-panel and concentrator photovoltaic (PV) systems. The objective of the work was to reduce substantially the cost of the array-field Balance-of-System (BOS) subsystems and site-specific design costs as compared to previous PV installations. These subsystems include site preparation, foundations, support structures, electrical writing, grounding, lightning protection, electromagnetic interference considerations, and controls. To reduce these BOS and design costs, standardized modular (building-block) designs for flat-panel and concentrator array fields have been developed that are fully integrated and optimized for lowest life-cycle costs. Using drawings and specifications now available, these building-block designs can be used in multiples to install various size array fields. The developed designs are immediately applicable (1982) and reduce the array-field BOS costs to a fraction of previous costs.

Ligand design for riboswitches, an emerging target class for novel antibiotics.

PubMed

Rekand, Illimar Hugo; Brenk, Ruth

2017-09-01

Riboswitches are cis-acting gene regulatory elements and constitute potential targets for new antibiotics. Recent studies in this field have started to explore these targets for drug discovery. New ligands found by fragment screening, design of analogs of the natural ligands or serendipitously by phenotypic screening have shown antibacterial effects in cell assays against a range of bacteria strains and in animal models. In this review, we highlight the most advanced drug design work of riboswitch ligands and discuss the challenges in the field with respect to the development of antibiotics with a new mechanism of action.

A program to study antiprotons in the cosmic rays: Arizona collaboration

NASA Technical Reports Server (NTRS)

Bowen, Theodore

1992-01-01

The Cherenkov detector designed and built for the LEAP (Low Energy AntiProton) experiment utilized a novel design to achieve appreciable sensitive area (02. sq m) with a refractive index of 1.25 in a magnetic fringe field region (500-1000 Gauss). The weight was held to only 64 kg by using 16 unshielded Hamamatsu R2490-01 photomultiplier tubes, each aligned with its local magnetic field. A filling and reservoir system for the highly volatile FC-72 liquid Cherenkov radiator also presented many design challenges. Relativistic particles yielded about 72 photoelectrons, total.

On the Design of Wide-Field X-ray Telescopes

NASA Technical Reports Server (NTRS)

Elsner, Ronald F.; O'Dell, Stephen L.; Ramsey, Brian D.; Weiskopf, Martin C.

2009-01-01

X-ray telescopes having a relatively wide field-of-view and spatial resolution vs. polar off-axis angle curves much flatter than the parabolic dependence characteristic of Wolter I designs are of great interest for surveys of the X-ray sky and potentially for study of the Sun s X-ray emission. We discuss the various considerations affecting the design of such telescopes, including the possible use of polynomial mirror surface prescriptions, a method of optimizing the polynomial coefficients, scaling laws for mirror segment length vs. intersection radius, the loss of on-axis spatial resolution, and the positioning of focal plane detectors.

Optical Isolators With Transverse Magnets

NASA Technical Reports Server (NTRS)

Fan, Yuan X.; Byer, Robert L.

1991-01-01

New design for isolator includes zigzag, forward-and-backward-pass beam path and use of transverse rather than longitudinal magnetic field. Design choices produce isolator with as large an aperture as desired using low-Verdet-constant glass rather than more expensive crystals. Uses commercially available permanent magnets in Faraday rotator. More compact and less expensive. Designed to transmit rectangular beam. Square cross section of beam extended to rectangular shape by increasing one dimension of glass without having to increase magnetic field. Potentially useful in laser systems involving slab lasers and amplifiers. Has applications to study of very-high-power lasers for fusion research.

[Design of Complex Cavity Structure in Air Route System of Automated Peritoneal Dialysis Machine].

PubMed

Quan, Xiaoliang

2017-07-30

This paper introduced problems about Automated Peritoneal Dialysis machine(APD) that the lack of technical issues such as the structural design of the complex cavities. To study the flow characteristics of this special structure, the application of ANSYS CFX software is used with k-ε turbulence model as the theoretical basis of fluid mechanics. The numerical simulation of flow field simulation result in the internal model can be gotten after the complex structure model is imported into ANSYS CFX module. Then, it will present the distribution of complex cavities inside the flow field and the flow characteristics parameter, which will provide an important reference design for APD design.

Guidelines for reporting evaluations based on observational methodology.

PubMed

Portell, Mariona; Anguera, M Teresa; Chacón-Moscoso, Salvador; Sanduvete-Chaves, Susana

2015-01-01

Observational methodology is one of the most suitable research designs for evaluating fidelity of implementation, especially in complex interventions. However, the conduct and reporting of observational studies is hampered by the absence of specific guidelines, such as those that exist for other evaluation designs. This lack of specific guidance poses a threat to the quality and transparency of these studies and also constitutes a considerable publication hurdle. The aim of this study thus was to draw up a set of proposed guidelines for reporting evaluations based on observational methodology. The guidelines were developed by triangulating three sources of information: observational studies performed in different fields by experts in observational methodology, reporting guidelines for general studies and studies with similar designs to observational studies, and proposals from experts in observational methodology at scientific meetings. We produced a list of guidelines grouped into three domains: intervention and expected outcomes, methods, and results. The result is a useful, carefully crafted set of simple guidelines for conducting and reporting observational studies in the field of program evaluation.

Near-term hybrid vehicle program, phase 1. Appendix C: Preliminary design data package

NASA Technical Reports Server (NTRS)

1979-01-01

The design methodology, the design decision rationale, the vehicle preliminary design summary, and the advanced technology developments are presented. The detailed vehicle design, the vehicle ride and handling and front structural crashworthiness analysis, the microcomputer control of the propulsion system, the design study of the battery switching circuit, the field chopper, and the battery charger, and the recent program refinements and computer results are presented.

Assessing Student Learning in the Major Field of Study

ERIC Educational Resources Information Center

Volkwein, J. Fredericks

2010-01-01

Assessing student attainment in the major field of study is increasingly important to employers and accrediting bodies alike. Construction and manufacturing firms do not like engineers who design faulty bridges and airplanes. Marketing firms want to hire students who understand the difference between a niche market and a global market. School…

Images of Imaging: Notes on Doing Longitudinal Field Work.

ERIC Educational Resources Information Center

Barley, Stephen R.

1990-01-01

Discusses the processes involved in a field study of technological change in radiology and how researchers can design a qualitative study and then collect data in a systematic and explicit manner. Illustrates the social and human problems of gaining entry into a research site, constructing a research role, and managing relationships. (63…

Why Most Published Research Findings Are False

PubMed Central

Ioannidis, John P. A.

2005-01-01

Summary There is increasing concern that most current published research findings are false. The probability that a research claim is true may depend on study power and bias, the number of other studies on the same question, and, importantly, the ratio of true to no relationships among the relationships probed in each scientific field. In this framework, a research finding is less likely to be true when the studies conducted in a field are smaller; when effect sizes are smaller; when there is a greater number and lesser preselection of tested relationships; where there is greater flexibility in designs, definitions, outcomes, and analytical modes; when there is greater financial and other interest and prejudice; and when more teams are involved in a scientific field in chase of statistical significance. Simulations show that for most study designs and settings, it is more likely for a research claim to be false than true. Moreover, for many current scientific fields, claimed research findings may often be simply accurate measures of the prevailing bias. In this essay, I discuss the implications of these problems for the conduct and interpretation of research. PMID:16060722

Reinventing Material Science - Continuum Magazine | NREL

Science.gov Websites

to reinvent an entire field of study, but that is exactly what the Center for Inverse Design is functional materials by developing an "inverse design" approach, powered by theory that guides experiment. The Center for Inverse Design was established as an Energy Frontier Research Center, funded by

Establishing Equivalence: Methodological Progress in Group-Matching Design and Analysis

ERIC Educational Resources Information Center

Kover, Sara T.; Atwood, Amy K.

2013-01-01

This methodological review draws attention to the challenges faced by intellectual and developmental disabilities researchers in the appropriate design and analysis of group comparison studies. We provide a brief overview of matching methodologies in the field, emphasizing group-matching designs used in behavioral research on cognition and…

Active Learning through Toy Design and Development

ERIC Educational Resources Information Center

Sirinterlikci, Arif; Zane, Linda; Sirinterlikci, Aleea L.

2009-01-01

This article presents an initiative that is based on active learning pedagogy by engaging elementary and middle school students in the toy design and development field. The case study presented in this article is about student learning experiences during their participation in the TOYchallenge National Toy Design Competition. Students followed the…

SOLERAS - Solar Controlled Environment Agriculture Project. Final report, Volume 4. Saudi Engineering Solar Energy Applications System Design Study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1985-01-01

Literature summarizing a study on the Saudi Arabian solar controlled environment agriculture system is presented. Specifications and performance requirements for the system components are revealed. Detailed performance and cost analyses are used to determine the optimum design. A preliminary design of an engineering field test is included. Some weather data are provided for Riyadh, Saudi Arabia. (BCS)

The Impact of Ideology on the Interaction between Tutors and Students in the Education of Industrial Design: A Case Study in Taiwan

ERIC Educational Resources Information Center

Hsiao, Hsi-Chi; Cheng, Yung-Shin

2006-01-01

This paper applies the concept of ideology to the field of design education. Specifically, this study explores the potential impact of ideology on the interaction between tutors and students involved in the education of industrial design in Taiwan. Particular emphasis is placed upon the instruction of the core curriculum. The present investigation…

Effects of Anode Flow Field Design on CO2 Bubble Behavior in μDMFC

PubMed Central

Li, Miaomiao; Liang, Junsheng; Liu, Chong; Sun, Gongquan; Zhao, Gang

2009-01-01

Clogging of anode flow channels by CO2 bubbles is a vital problem for further performance improvements of the micro direct methanol fuel cell (μDMFC). In this paper, a new type anode structure using the concept of the non-equipotent serpentine flow field (NESFF) to solve this problem was designed, fabricated and tested. Experiments comparing the μDMFC with and without this type of anode flow field were implemented using a home-made test loop. Results show that the mean-value, amplitude and frequency of the inlet-to-outlet pressure drops in the NESFF is far lower than that in the traditional flow fields at high μDMFC output current. Furthermore, the sequential images of the CO2 bubbles as well as the μDMFC performance with different anode flow field pattern were also investigated, and the conclusions are in accordance with those derived from the pressure drop experiments. Results of this study indicate that the non-equipotent design of the μDMFC anode flow field can effectively mitigate the CO2 clogging in the flow channels, and hence lead to a significant promotion of the μDMFC performance. PMID:22412313

Multi scale modeling of 2450MHz electric field effects on microtubule mechanical properties.

PubMed

Setayandeh, S S; Lohrasebi, A

2016-11-01

Microtubule (MT) rigidity and response to 2450MHz electric fields were investigated, via multi scale modeling approach. For this purpose, six systems were designed and simulated to consider all types of feasible interactions between α and β monomers in MT, by using all atom molecular dynamics method. Subsequently, coarse grain modeling was used to design different lengths of MT. Investigation of effects of external 2450MHz electric field on MT showed MT less rigidity in the presence of such field, which may perturb its functions. Moreover, an additional computational setup was designed to study effects of 2450MHz field on MT response to AFM tip. It was found, more tip velocity led to MT faster transformation and less time was required to change MT elastic response to plastic one, applying constant radius. Moreover it was observed smaller tip caused to increase required time to change MT elastic response to plastic one, considering constant velocity. Furthermore, exposing MT to 2450MHz field led to no significant changes in MT response to AFM tip, but quick change in MT elastic response to plastic one. Copyright © 2016 Elsevier Inc. All rights reserved.

Estimation of polarization distribution on gold nanorods system from hierarchical features of optical near-field

NASA Astrophysics Data System (ADS)

Uchiyama, Kazuharu; Nishikawa, Naoki; Nakagomi, Ryo; Kobayashi, Kiyoshi; Hori, Hirokazu

2018-02-01

To design optoelectronic functionalities in nanometer scale based on interactions of electronic system with optical near-fields, it is essential to evaluate the relationship between optical near-fields and their sources. Several theoretical studies have been performed, so far, to analyze such complex relationship to design the interaction fields of several specific scales. In this study, we have performed detailed and high-precision measurements of optical near-field structures woven by a large number of independent polarizations generated in the gold nanorods array under laser light irradiation at the resonant frequency. We have accumulated the multi-layered data of optical near-field imaging at different heights above the planar surface with the resolution of several nm by a STM-assisted scanning near-field optical microscope. Based on these data, we have performed an inverse calculation to estimate the position, direction, and strength of the local polarization buried under the flat surface of the sample. As a result of the inverse operation, we have confirmed that the complexities in the nanometer scale optical near-fields could be reconstructed by combinations of induced polarization in each gold nanorod. We have demonstrated the hierarchical properties of optical near-fields based on spatial frequency expansion and superposition of dipole fields to provide insightful information for applications such for secure multi-layered information storage.

Assessment of the Bordas-Carnot Losses within the diffuser of tidal turbines using far-field and near-field CFD models.

NASA Astrophysics Data System (ADS)

Hajaali, Arthur

2017-04-01

This project has for ambition to analyse and further the general understanding on cross-flows interactions and behaviours at the mouth of a mini/small tidal hydropower plant and a river. Although, the study of these interactions could benefit and find applications in multiple hydraulic problems, this project concentrates its focus on the influence of the transposed turbulences generated by the cross-flow into the diffuser. These eddies affect the overall performance and efficiency of the bulb-turbines by minimizing the pressure recovery. In the past, these turbulences were accounted with the implementation of the Bordas-Carnot losses coefficient for the design of tidal project using bulb-turbines. The bulb turbine technology has been the interest and subject of many scientific papers but most of them concentrate and narrow their focus on the design of the rotor, blades and combiner. This project wants to focus the design of the diffuser by performing an analysis on the development of eddies and the turbulences using computational fluid dynamic (CFD) models. The Severn estuary is endowed with one of the highest tidal range around the hemisphere. The first part of the research requires to select case studies sites such as Briton-Ferry to virtually design mini-tidal plant in 0-Dimentional (D), 2D and 3D modelling to study development and behaviour of turbulences within the diffuser. The far-field model represents the marine environment prior and after the structure where bulb turbines are located. The near-field modelling has allowed researcher to study at much higher resolution and precision the design of a single turbine feeding model with predetermined and fix boundary condition. For this reason, a near-field model is required to study in depth the behaviour and evolution of the turbulence with the diffuser. One of the main challenge and advancement of this research is to find a methodology and system to link the far-field and near-field modelling to produce an interacting and dynamic model. The first model of the tidal plant in 0D is near completion and will provide a rough idea of the energy potential of the Briton-Ferry site based on the operation type of the turbine. Simultaneously, the 2D modelling of the area was initiated a week ago using TELEMAC-2D and Bluekenue as pre/post-processor. The hope for the conference would be to present result on the turbulence occurring at the mouth of the river and the structure in the far-field model and to have started the near-field model on Hydro3D with some idea on ways to connect it adequately to the far-field model. Ulterior to the conference next September, the ongoing collaboration with GE will benefit the validation of the computational model as the second part of this research will consist of building a bulb turbine and the diffuser with their facilities and laboratory in Grenoble (France). Once the collection of the necessary experimental observations on the turbulence within the diffuser will be complete, the model will be refined. Finally, it will be attempt to improve the design of the diffuser.

How Learning Environments Can Stimulate Student Imagination

ERIC Educational Resources Information Center

Liang, Chaoyun; Hsu, Yuling; Huang, Yinghsiu; Chen, Sheng-Chih

2012-01-01

The purpose of this study was to investigate an array of environmental factors that can stimulate imagination and explore how these factors manifest in different design phases. The participants of this study were students in the field of educational technology from four universities across Taiwan. The instructional design process was divided into…

Pavement design and performance studies : progress report no. 4 on phase A, performance study of typical Virginia pavements.

DOT National Transportation Integrated Search

1970-01-01

The performance of in-service typical Virginia flexible and rigid pavements in all areas of the state is under evaluation. The objectives are to provide a ready reference for designers and field engineers and to provide background information for des...

Accumulating Knowledge: When Are Reading Intervention Results Meaningful?

ERIC Educational Resources Information Center

Fletcher, Jack M.; Wagner, Richard K.

2014-01-01

The three target articles provide examples of intervention studies that are excellent models for the field. They rely on rigorous and elegant designs, the interventions are motivated by attention to underlying theoretical mechanisms, and longitudinal designs are used to examine the duration of effects of interventions that occur. When studies are…

Helicopter far-field acoustic levels as a function of reduced main-rotor advancing blade-tip Mach number

NASA Technical Reports Server (NTRS)

Mueller, Arnold W.; Smith, Charles D.; Lemasurier, Philip

1990-01-01

During the design of a helicopter, the weight, engine, rotor speed, and rotor geometry are given significant attention when considering the specific operations for which the helicopter will be used. However, the noise radiated from the helicopter and its relationship to the design variables is currently not well modeled with only a limited set of full-scale field test data to study. In general, limited field data have shown that reduced main-rotor advancing blade-tip Mach numbers result in reduced far-field noise levels. The status of a recent helicopter noise research project is reviewed. It is designed to provide flight experimental data which may be used to further understand helicopter main-rotor advancing blade-tip Mach number effects on far-field acoustic levels. Preliminary results are presented relative to tests conducted with a Sikorsky S-76A helicopter operating with both the rotor speed and the flight speed as the control variable. The rotor speed was operated within the range of 107 to 90 percent NR at nominal forward speeds of 35, 100, and 155 knots.

Monte Carlo-based diode design for correction-less small field dosimetry.

PubMed

Charles, P H; Crowe, S B; Kairn, T; Knight, R T; Hill, B; Kenny, J; Langton, C M; Trapp, J V

2013-07-07

Due to their small collecting volume, diodes are commonly used in small field dosimetry. However, the relative sensitivity of a diode increases with decreasing small field size. Conversely, small air gaps have been shown to cause a significant decrease in the sensitivity of a detector as the field size is decreased. Therefore, this study uses Monte Carlo simulations to look at introducing air upstream to diodes such that they measure with a constant sensitivity across all field sizes in small field dosimetry. Varying thicknesses of air were introduced onto the upstream end of two commercial diodes (PTW 60016 photon diode and PTW 60017 electron diode), as well as a theoretical unenclosed silicon chip using field sizes as small as 5 mm × 5 mm. The metric D(w,Q)/D(Det,Q) used in this study represents the ratio of the dose to a point of water to the dose to the diode active volume, for a particular field size and location. The optimal thickness of air required to provide a constant sensitivity across all small field sizes was found by plotting D(w,Q)/D(Det,Q) as a function of introduced air gap size for various field sizes, and finding the intersection point of these plots. That is, the point at which D(w,Q)/D(Det,Q) was constant for all field sizes was found. The optimal thickness of air was calculated to be 3.3, 1.15 and 0.10 mm for the photon diode, electron diode and unenclosed silicon chip, respectively. The variation in these results was due to the different design of each detector. When calculated with the new diode design incorporating the upstream air gap, k(f(clin),f(msr))(Q(clin),Q(msr)) was equal to unity to within statistical uncertainty (0.5%) for all three diodes. Cross-axis profile measurements were also improved with the new detector design. The upstream air gap could be implanted on the commercial diodes via a cap consisting of the air cavity surrounded by water equivalent material. The results for the unclosed silicon chip show that an ideal small field dosimetry diode could be created by using a silicon chip with a small amount of air above it.

High-performance superconductors for Fusion Nuclear Science Facility

DOE PAGES

Zhai, Yuhu; Kessel, Chuck; Barth, Christian; ...

2016-11-09

High-performance superconducting magnets play an important role in the design of the next step large-scale, high-field fusion reactors such as the fusion nuclear science facility (FNSF) and the spherical tokamak (ST) pilot plant beyond ITER. Here, Princeton Plasma Physics Laboratory is currently leading the design studies of the FNSF and the ST pilot plant study. ITER, which is under construction in the south of France, utilizes the state-of-the-art low temperature superconducting magnet technology based on the cable-in-conduit conductor design, where over a thousand multifilament Nb 3Sn superconducting strands are twisted together to form a high-current-carrying cable inserted into a steelmore » jacket for coil windings. We present design options of the high-performance superconductors in the winding pack for the FNSF toroidal field magnet system based on the toroidal field radial build from the system code. For the low temperature superconductor options, the advanced J cNb 3Sn RRP strands (J c > 1000 A/mm 2 at 16 T, 4 K) from Oxford Superconducting Technology are under consideration. For the high-temperature superconductor options, the rectangular-shaped high-current HTS cable made of stacked YBCO tapes will be considered to validate feasibility of TF coil winding pack design for the ST-FNSF magnets.« less

High-performance superconductors for Fusion Nuclear Science Facility

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhai, Yuhu; Kessel, Chuck; Barth, Christian

High-performance superconducting magnets play an important role in the design of the next step large-scale, high-field fusion reactors such as the fusion nuclear science facility (FNSF) and the spherical tokamak (ST) pilot plant beyond ITER. Here, Princeton Plasma Physics Laboratory is currently leading the design studies of the FNSF and the ST pilot plant study. ITER, which is under construction in the south of France, utilizes the state-of-the-art low temperature superconducting magnet technology based on the cable-in-conduit conductor design, where over a thousand multifilament Nb 3Sn superconducting strands are twisted together to form a high-current-carrying cable inserted into a steelmore » jacket for coil windings. We present design options of the high-performance superconductors in the winding pack for the FNSF toroidal field magnet system based on the toroidal field radial build from the system code. For the low temperature superconductor options, the advanced J cNb 3Sn RRP strands (J c > 1000 A/mm 2 at 16 T, 4 K) from Oxford Superconducting Technology are under consideration. For the high-temperature superconductor options, the rectangular-shaped high-current HTS cable made of stacked YBCO tapes will be considered to validate feasibility of TF coil winding pack design for the ST-FNSF magnets.« less

How Long Should a Training Program Be? A Field Study of "Rules-of-Thumb"

ERIC Educational Resources Information Center

Cole, Nina

2008-01-01

Purpose: This study aims to examine the question of how long a behavioral skills training program should be in order to result in measurable behavioral change. Design/methodology/approach: An empirical field study was conducted to compare two different lengths of time for a managerial skills training program aimed at achieving behavioral change.…

Evaluation and verification of two systems for mechanistic structural design of asphalt concrete pavements in Nebraska

NASA Astrophysics Data System (ADS)

Sneddon, R. V.

1982-07-01

The VESY-3-A mechanistic design system for asphalt pavements was field verified for three pavement sections at two test sites in Nebraska. PSI predictions from VESYS were in good agreement with field measurements for a 20 year old 3 layer pavement located near Elmwood, Nebraska. Field measured PSI values for an 8 in. full depth pavement also agreed with VESYS predictions for the study period. Rut depth estimates from the model were small and were in general agreement with field measurements. Cracking estimates were poor and tended to underestimate the time required to develop observable fatigue cracking in the field. Asphalt, base course and subgrade materials were tested in a 4.0 in. diameter modified triaxial cell. Test procedures used dynamic conditioning and rest periods to simulate service conditions.

Active magnetic radiation shielding system analysis and key technologies.

PubMed

Washburn, S A; Blattnig, S R; Singleterry, R C; Westover, S C

2015-01-01

Many active magnetic shielding designs have been proposed in order to reduce the radiation exposure received by astronauts on long duration, deep space missions. While these designs are promising, they pose significant engineering challenges. This work presents a survey of the major systems required for such unconfined magnetic field design, allowing the identification of key technologies for future development. Basic mass calculations are developed for each system and are used to determine the resulting galactic cosmic radiation exposure for a generic solenoid design, using a range of magnetic field strength and thickness values, allowing some of the basic characteristics of such a design to be observed. This study focuses on a solenoid shaped, active magnetic shield design; however, many of the principles discussed are applicable regardless of the exact design configuration, particularly the key technologies cited. Copyright © 2015 The Committee on Space Research (COSPAR). All rights reserved.

Tracer tomography: design concepts and field experiments using heat as a tracer.

PubMed

Doro, Kennedy O; Cirpka, Olaf A; Leven, Carsten

2015-04-01

Numerical and laboratory studies have provided evidence that combining hydraulic tomography with tomographic tracer tests could improve the estimation of hydraulic conductivity compared with using hydraulic data alone. Field demonstrations, however, have been lacking so far, which we attribute to experimental difficulties. In this study, we present a conceptual design and experimental applications of tracer tomography at the field scale using heat as a tracer. In our experimental design, we improve active heat tracer testing by minimizing possible effects of heat losses, buoyancy, viscosity, and changing boundary conditions. We also utilize a cost-effective approach of measuring temperature changes in situ at high resolution. We apply the presented method to the 8 m thick heterogeneous, sandy gravel, alluvial aquifer at the Lauswiesen Hydrogeological Research Site in Tübingen, Germany. Results of our tomographic heat-tracer experiments are in line with earlier work on characterizing the aquifer at the test site. We demonstrate from the experimental perspective that tracer tomography is applicable and suitable at the field scale using heat as a tracer. The experimental results also demonstrate the potential of heat-tracer tomography as a cost-effective means for characterizing aquifer heterogeneity. © 2014, National Ground Water Association.

Field demonstration of the combined effects of absorption and evapotranspiration on septic system drainfield capacity.

PubMed

Rainwater, Ken; Jackson, Andrew; Ingram, Wesley; Lee, Chang Yong; Thompson, David; Mollhagen, Tony; Ramsey, Heyward; Urban, Lloyd

2005-01-01

Drainfields for disposal of septic tank effluents are typically designed by considering the loss of water by either upward evapotranspiration into the atmosphere or lateral and downward absorption into the adjacent soil. While this approach is appropriate for evapotranspiration systems, absorption systems allow water loss by both mechanisms. It was proposed that, in areas where high evapotranspiration rates coincide with permeable soils, drainfield sizes could be substantially reduced by accounting for both mechanisms. A two-year field demonstration was conducted to determine appropriate design criteria for areas typical of the Texas High Plains. The study consisted of evaluating the long-term acceptance rates for three different drainfield configurations: evapotranspiration only, absorption only, and combined conditions. A second field demonstration repeated the experiments for additional observation of the combined evapotranspiration and absorption and achieved similar results as the first study. The field tests indicated that the current design loading criteria may be increased by at least a factor of two for the Texas High Plains region and other Texas areas with similar soil composition and evapotranspiration rates, while still retaining a factor of safety of two.

The Relationship of Field Dependent/Independent Cognitive Styles, Stimuli Variability and Time Factor on Student Achievement.

ERIC Educational Resources Information Center

Atang, Christopher I.

The effects of black and white and color illustrations on student achievement were studied to investigate the relationships between cognitive styles and instructional design. Field dependence (FD) and field independence (FI) were chosen as the cognitive style variables. Subjects were 85 freshman students in the Iowa State University Psychology…

NHEXAS PHASE I REGION 5 STUDY--STANDARD OPERATING PROCEDURE--HANDLING QUALITY CONTROL SAMPLES IN THE FIELD (RTI/ACS-AP-209-090)

EPA Science Inventory

This protocol describes how quality control samples should be handled in the field, and was designed as a quick reference source for the field staff. The protocol describes quality control samples for air-VOCs, air-particles, water samples, house dust, soil, urine, blood, hair, a...

Wolves Are Beautiful and Proud: Science Learning from a School Field Trip

ERIC Educational Resources Information Center

Glick, Marilyn Petty; Samarapungavan, Ala

2008-01-01

This research examines the impact of related classroom activities on fourth grade students' science learning from a school field trip. The current study draws upon research in psychology and education to create an intervention that is designed to enhance what students learn from school science field trips. The intervention comprises a set of…

Exploring Group Cohesion in a Higher Education Field Experience

ERIC Educational Resources Information Center

Malcarne, Brian Keith

2012-01-01

The purpose of this study was to gain understanding into the experience of group cohesion for university students participating in an academic field experience. A mixed methods approach was used following a two-phase, sequential research design to help provide a more complete explanation of how group cohesion was impacted by the field experience.…

Microwave remote sensing laboratory design

NASA Technical Reports Server (NTRS)

Friedman, E.

1979-01-01

Application of active and passive microwave remote sensing to the study of ocean pollution is discussed. Previous research efforts, both in the field and in the laboratory were surveyed to derive guidance for the design of a laboratory program of research. The essential issues include: choice of radar or radiometry as the observational technique; choice of laboratory or field as the research site; choice of operating frequency; tank sizes and material; techniques for wave generation and appropriate wavelength spectrum; methods for controlling and disposing of pollutants used in the research; and pollutants other than oil which could or should be studied.

Empirical studies of design software: Implications for software engineering environments

NASA Technical Reports Server (NTRS)

Krasner, Herb

1988-01-01

The empirical studies team of MCC's Design Process Group conducted three studies in 1986-87 in order to gather data on professionals designing software systems in a range of situations. The first study (the Lift Experiment) used thinking aloud protocols in a controlled laboratory setting to study the cognitive processes of individual designers. The second study (the Object Server Project) involved the observation, videotaping, and data collection of a design team of a medium-sized development project over several months in order to study team dynamics. The third study (the Field Study) involved interviews with the personnel from 19 large development projects in the MCC shareholders in order to study how the process of design is affected by organizationl and project behavior. The focus of this report will be on key observations of design process (at several levels) and their implications for the design of environments.

Measurements of crossed-field demagnetisation rate of trapped field magnets at high frequencies and below 77 K

NASA Astrophysics Data System (ADS)

Baskys, A.; Patel, A.; Glowacki, B. A.

2018-06-01

Design requirements of the next generation of electric aircraft place stringent requirements on the power density required from electric motors. A future prototype planned in the scope of the European project ‘Advanced Superconducting Motor Experimental Demonstrator’ (ASuMED) considers a permanent magnet synchronous motor, where the conventional ferromagnets are replaced with superconducting trapped field magnets, which promise higher flux densities and thus higher output power without adding weight. Previous work has indicated that stacks of tape show lower cross-field demagnetisation rates to bulk (RE)BCO whilst retaining similar performance for their size, however the crossed-field demagnetisation rate has not been studied in the temperature, the magnetic field and frequency range that are relevant for the operational prototype motor. This work investigates crossed-field demagnetisation in 2G high temperature superconducting stacks at temperatures below 77 K and a frequency range above 10 Hz. This information is crucial in developing designs and determining operational time before re-magnetisation could be required.

Field test of a motorcycle safety education course for novice riders

DOT National Transportation Integrated Search

1982-07-01

The purpose of this study was to subject the Motorcycle Safety Foundation's Motorcycle Rider Course (MRC) to a large-scale field test designed to evaluate the following aspects of the course: (1) Instructional Effectiveness, (2) User Acceptance, and ...

Design and Construction of Field Reversed Configuration Plasma Chamber for Plasma Material Interaction Studies

NASA Astrophysics Data System (ADS)

Smith, DuWayne L.

A Field Reversed Configuration (FRC) plasma source was designed and constructed to conduct high energy plasma-materials interaction studies. The purpose of these studies is the development of advanced materials for use in plasma based electric propulsion systems and nuclear fusion containment vessels. Outlined within this thesis is the basic concept of FRC plasmoid creation, an overview of the device design and integration of various diagnostics systems for plasma conditions and characterization, discussion on the variety of material defects resulting from the plasma exposure with methods and tools designed for characterization. Using a Michelson interferometer it was determined that the FRC plasma densities are on the order of ~1021 m-3. A novel dynamic pressure probe was created to measure ion velocities averaging 300 km/s. Compensating flux loop arrays were used to measure magnetic field strength and verify the existence of the FRC plasmoid and when used in combination with density measurements it was determined that the average ion temperatures are ~130 eV. X-ray Photoelectron Spectroscopy (XPS) was employed as a means of characterizing the size and shape of the plasma jet in the sample exposure positions. SEM results from preliminary studies reveal significant morphological changes on plasma facing material surfaces, and use of XRD to elucidate fuel gas-ion implantation strain rates correlated to plasma exposure energies.

Magnet Design Considerations for Fusion Nuclear Science Facility

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhai, Y.; Kessel, C.; El-Guebaly, L.

2016-06-01

The Fusion Nuclear Science Facility (FNSF) is a nuclear confinement facility that provides a fusion environment with components of the reactor integrated together to bridge the technical gaps of burning plasma and nuclear science between the International Thermonuclear Experimental Reactor (ITER) and the demonstration power plant (DEMO). Compared with ITER, the FNSF is smaller in size but generates much higher magnetic field, i.e., 30 times higher neutron fluence with three orders of magnitude longer plasma operation at higher operating temperatures for structures surrounding the plasma. Input parameters to the magnet design from system code analysis include magnetic field of 7.5more » T at the plasma center with a plasma major radius of 4.8 m and a minor radius of 1.2 m and a peak field of 15.5 T on the toroidal field (TF) coils for the FNSF. Both low-temperature superconductors (LTS) and high-temperature superconductors (HTS) are considered for the FNSF magnet design based on the state-of-the-art fusion magnet technology. The higher magnetic field can be achieved by using the high-performance ternary restacked-rod process Nb3Sn strands for TF magnets. The circular cable-in-conduit conductor (CICC) design similar to ITER magnets and a high-aspect-ratio rectangular CICC design are evaluated for FNSF magnets, but low-activation-jacket materials may need to be selected. The conductor design concept and TF coil winding pack composition and dimension based on the horizontal maintenance schemes are discussed. Neutron radiation limits for the LTS and HTS superconductors and electrical insulation materials are also reviewed based on the available materials previously tested. The material radiation limits for FNSF magnets are defined as part of the conceptual design studies for FNSF magnets.« less

Magnet design considerations for Fusion Nuclear Science Facility

DOE PAGES

Zhai, Yuhu; Kessel, Chuck; El-guebaly, Laila; ...

2016-02-25

The Fusion Nuclear Science Facility (FNSF) is a nuclear confinement facility to provide a fusion environment with components of the reactor integrated together to bridge the technical gaps of burning plasma and nuclear science between ITER and the demonstration power plant (DEMO). Compared to ITER, the FNSF is smaller in size but generates much higher magnetic field, 30 times higher neutron fluence with 3 orders of magnitude longer plasma operation at higher operating temperatures for structures surrounding the plasma. Input parameters to the magnet design from system code analysis include magnetic field of 7.5 T at the plasma center withmore » plasma major radius of 4.8 m and minor radius of 1.2 m, and a peak field of 15.5 T on the TF coils for FNSF. Both low temperature superconductor (LTS) and high temperature superconductor (HTS) are considered for the FNSF magnet design based on the state-of-the-art fusion magnet technology. The higher magnetic field can be achieved by using the high performance ternary Restack Rod Process (RRP) Nb3Sn strands for toroidal field (TF) magnets. The circular cable-in-conduit conductor (CICC) design similar to ITER magnets and a high aspect ratio rectangular CICC design are evaluated for FNSF magnets but low activation jacket materials may need to be selected. The conductor design concept and TF coil winding pack composition and dimension based on the horizontal maintenance schemes are discussed. Neutron radiation limits for the LTS and HTS superconductors and electrical insulation materials are also reviewed based on the available materials previously tested. As a result, the material radiation limits for FNSF magnets are defined as part of the conceptual design studies for FNSF magnets.« less

Preliminary Mechanical Design Study of the Hollow Electron Lens for HL-LHC

NASA Astrophysics Data System (ADS)

Zanoni, Carlo; Gobbi, Giorgia; Perini, Diego; Stancari, Giulio

2017-07-01

A Hollow Electron Lens (HEL) has been proposed in order to improve performance of halo control and collimation in the Large Hadron Collider in view of its High Luminosity upgrade (HL-LHC). The concept is based on a hollow beam of electrons that travels around the protons for a few meters. The electron beam is produced by a cathode and then guided by a strong magnetic field. The first step of the design is the definition of the magnetic field that drives the electron trajectories. The estimation of such trajectories by means of a dedicated MATLAB tool is presented. The influence of the main geometrical and electrical parameters is analyzed and discussed. Then, the main mechanical design choices for the solenoids, cryostats gun and collector are described. The aim of this paper is to provide an overview of the feasibility study of the Electron Lens for LHC. The methods used in this study also serve as examples for future mechanical and integration designs of similar devices.

Preliminary Mechanical Design Study of the Hollow Electron Lens for HL-LHC

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zanoni, Carlo; Gobbi, Giorgia; Perini, Diego

A Hollow Electron Lens (HEL) has been proposed in order to improve performance of halo control and collimation in the Large Hadron Collider in view of its High Luminosity upgrade (HL-LHC). The concept is based on a hollow beam of electrons that travels around the protons for a few meters. The electron beam is produced by a cathode and then guided by a strong magnetic field. The first step of the design is the definition of the magnetic field that drives the electron trajectories. The estimation of such trajectories by means of a dedicated MATLAB tool is presented. The influencemore » of the main geometrical and electrical parameters is analyzed and discussed. Then, the main mechanical design choices for the solenoids, cryostats gun and collector are described. The aim of this paper is to provide an overview of the feasibility study of the Electron Lens for LHC. The methods used in this study also serve as examples for future mechanical and integration designs of similar devices.« less

From Rhetoric to Reality: Case Studies of Two Fifth Grade Science Teachers to Inform Reform

ERIC Educational Resources Information Center

Maynard, Kathie Jo

2013-01-01

The purpose of this qualitative study was to explore two elementary teachers' implementation of engineering design over two academic years and to describe how their teaching practice changed over the two instructional cycles. This study used field notes and audio transcripts of the teachers during their engineering design teaching, written…

Design of a Horizontal Penetrometer for Measuring On-the-Go Soil Resistance

PubMed Central

Topakci, Mehmet; Unal, Ilker; Canakci, Murad; Celik, Huseyin Kursat; Karayel, Davut

2010-01-01

Soil compaction is one of the main negative factors that limits plant growth and crop yield. Therefore, it is important to determine the soil resistance level and map it for the field to find solutions for the negative effects of the compaction. Nowadays, high powered communication technology and computers help us on this issue within the approach of precision agriculture applications. This study is focused on the design of a penetrometer, which can make instantaneous soil resistance measurements in the soil horizontally and data acquisition software based on the GPS (Global Positioning System). The penetrometer was designed using commercial 3D parametric solid modelling design software. The data acquisition software was developed in Microsoft Visual Basic.NET programming language. After the design of the system, manufacturing and assembly of the system was completed and then a field experiment was carried out. According to the data from GPS and penetration resistance values which are collected in Microsoft SQL Server database, a Kriging method by ArcGIS was used and soil resistance was mapped in the field for a soil depth of 40 cm. During operation, no faults, either in mechanical and software parts, were seen. As a result, soil resistance values of 0.2 MPa and 3 MPa were obtained as minimum and maximum values, respectively. In conclusion, the experimental results showed that the designed system works quite well in the field and the horizontal penetrometer is a practical tool for providing on-line soil resistance measurements. This study contributes to further research for the development of on-line soil resistance measurements and mapping within the precision agriculture applications. PMID:22163410

Design of a horizontal penetrometer for measuring on-the-go soil resistance.

PubMed

Topakci, Mehmet; Unal, Ilker; Canakci, Murad; Celik, Huseyin Kursat; Karayel, Davut

2010-01-01

Soil compaction is one of the main negative factors that limits plant growth and crop yield. Therefore, it is important to determine the soil resistance level and map it for the field to find solutions for the negative effects of the compaction. Nowadays, high powered communication technology and computers help us on this issue within the approach of precision agriculture applications. This study is focused on the design of a penetrometer, which can make instantaneous soil resistance measurements in the soil horizontally and data acquisition software based on the GPS (Global Positioning System). The penetrometer was designed using commercial 3D parametric solid modelling design software. The data acquisition software was developed in Microsoft Visual Basic.NET programming language. After the design of the system, manufacturing and assembly of the system was completed and then a field experiment was carried out. According to the data from GPS and penetration resistance values which are collected in Microsoft SQL Server database, a Kriging method by ArcGIS was used and soil resistance was mapped in the field for a soil depth of 40 cm. During operation, no faults, either in mechanical and software parts, were seen. As a result, soil resistance values of 0.2 MPa and 3 MPa were obtained as minimum and maximum values, respectively. In conclusion, the experimental results showed that the designed system works quite well in the field and the horizontal penetrometer is a practical tool for providing on-line soil resistance measurements. This study contributes to further research for the development of on-line soil resistance measurements and mapping within the precision agriculture applications.

Design and Simulation of a Birdcage Coil using CST Studio Suite for Application at 7T

NASA Astrophysics Data System (ADS)

Palau Tomas, Bernat; Li, Houmin; Anjum, M. R.

2013-12-01

This work describes the study of coils for Magnetic Resonance Imaging (MRI) applications. The principal objective is the design of a birdcage Radio Frequency (RF) coil to use in a 7 Tesla (7T) scanner. Higher strength field generates a better SNR and increased chemical shift effect, improving spectral fat suppression and spectroscopy. Moreover, a better SNR increases the spatial resolution or reduces the imaging time. This research work presented recent developments based on high field 7T design using CST studio. The birdcage coil achieves circular polarization and generates a high homogeneous radio frequency magnetic field under many conditions. Design of a Birdcage coil for a 7T to obtain the images from s mall animals (i.e. mouse). It opens the door to design and construct a Birdcage coil for a 7T to obtain human brain images. Firstly we design a birdcage coil then the results are obtained with simulator CST Wave Studio, creating a 3D model and generating a simulation. Finally the parameters are re adjusted to obtain our desired Larmor frequency 298.2 MHz for a correct operation in 7T. This research work demonstrates the theoretical results from our design and shows the designed antenna behavior.

Prototype Imaging Spectrograph for Coronagraphic Exoplanet Studies (PISCES) for WFIRST/AFTA

NASA Technical Reports Server (NTRS)

Gong, Qian; Mcelwain, Michael; Greeley, Bradford; Grammer, Bryan; Marx, Catherine; Memarsadeghi, Nargess; Stapelfeldt, Karl; Hilton, George; Sayson, Jorge Llop; Perrin, Marshall;

Prototype Imaging Spectrograph for Coronagraphic Exoplanet Studies (PISCES) for WFIRST-AFTA

NASA Technical Reports Server (NTRS)

Gong, Qian; Mcelwain, Michael; Greeley, Bradford; Grammer, Bryan; Marx, Catherine; Memarsadeghi, Nargess; Stapelfeldt, Karl; Hilton, George; Sayson, Jorge Llop; Perrin, Marshall;

Achieving bifunctional cloak via combination of passive and active schemes

NASA Astrophysics Data System (ADS)

Lan, Chuwen; Bi, Ke; Gao, Zehua; Li, Bo; Zhou, Ji

2016-11-01

In this study, a simple and delicate approach to realizing manipulation of multi-physics field simultaneously through combination of passive and active schemes is proposed. In the design, one physical field is manipulated with passive scheme while the other with active scheme. As a proof of this concept, a bifunctional device is designed and fabricated to behave as electric and thermal invisibility cloak simultaneously. It is found that the experimental results are consistent with the simulated ones well, confirming the feasibility of our method. Furthermore, the proposed method could also be extended to other multi-physics fields, which might lead to potential applications in thermal, electric, and acoustic areas.

The importance of replication in wildlife research

USGS Publications Warehouse

Johnson, D.H.

2002-01-01

Wildlife ecology and management studies have been widely criticized for deficiencies in design or analysis. Manipulative experiments--with controls, randomization, and replication in space and time--provide powerful ways of learning about natural systems and establishing causal relationships, but such studies are rare in our field. Observational studies and sample surveys are more common; they also require appropriate design and analysis. More important than the design and analysis of individual studies is metareplication: replication of entire studies. Similar conclusions obtained from studies of the same phenomenon conducted under widely differing conditions will give us greater confidence in the generality of those findings than would any single study, however well designed and executed.

Design and fabrication of a 3D-structured gold film with nanopores for local electric field enhancement in the pore

NASA Astrophysics Data System (ADS)

Grant-Jacob, James A.; Zin Oo, Swe; Carpignano, Francesca; Boden, Stuart A.; Brocklesby, William S.; Charlton, Martin D. B.; Melvin, Tracy

2016-02-01

Three-dimensionally structured gold membrane films with nanopores of defined, periodic geometries are designed and fabricated to provide the spatially localised enhancement of electric fields by manipulation of the plasmons inside nanopores. Square nanopores of different size and orientation relative to the pyramid are considered for films in aqueous and air environments, which allow for control of the position of electric fields within the structure. Designs suitable for use with 780 nm light were created. Here, periodic pyramidal cavities produced by potassium hydroxide etching to the {111} planes of (100) silicon substrates are used as templates for creating a periodic, pyramidal structured, free-standing thin gold film. Consistent with the findings from the theoretical studies, a nano-sized hole of 50 nm square was milled through the gold film at a specific location in the cavity to provide electric field control which can subsequently used for enhancement of fluorescence or Raman scattering of molecules in the nanopore.

Design and fabrication of a 3D-structured gold film with nanopores for local electric field enhancement in the pore.

PubMed

Grant-Jacob, James A; Oo, Swe Zin; Carpignano, Francesca; Boden, Stuart A; Brocklesby, William S; Charlton, Martin D B; Melvin, Tracy

2016-02-12

Three-dimensionally structured gold membrane films with nanopores of defined, periodic geometries are designed and fabricated to provide the spatially localised enhancement of electric fields by manipulation of the plasmons inside nanopores. Square nanopores of different size and orientation relative to the pyramid are considered for films in aqueous and air environments, which allow for control of the position of electric fields within the structure. Designs suitable for use with 780 nm light were created. Here, periodic pyramidal cavities produced by potassium hydroxide etching to the {111} planes of (100) silicon substrates are used as templates for creating a periodic, pyramidal structured, free-standing thin gold film. Consistent with the findings from the theoretical studies, a nano-sized hole of 50 nm square was milled through the gold film at a specific location in the cavity to provide electric field control which can subsequently used for enhancement of fluorescence or Raman scattering of molecules in the nanopore.

Design study of electron cyclotron resonance-ion plasma accelerator for heavy ion cancer therapy.

PubMed

Inoue, T; Hattori, T; Sugimoto, S; Sasai, K

2014-02-01

Electron Cyclotron Resonance-Ion Plasma Accelerator (ECR-IPAC) device, which theoretically can accelerate multiple charged ions to several hundred MeV with short acceleration length, has been proposed. The acceleration mechanism is based on the combination of two physical principles, plasma electron ion adiabatic ejection (PLEIADE) and Gyromagnetic Autoresonance (GYRAC). In this study, we have designed the proof of principle machine ECR-IPAC device and simulated the electromagnetic field distribution generating in the resonance cavity. ECR-IPAC device consisted of three parts, ECR ion source section, GYRAC section, and PLEIADE section. ECR ion source section and PLEIADE section were designed using several multi-turn solenoid coils and sextupole magnets, and GYRAC section was designed using 10 turns coil. The structure of ECR-IPAC device was the cylindrical shape, and the total length was 1024 mm and the maximum diameter was 580 mm. The magnetic field distribution, which maintains the stable acceleration of plasma, was generated on the acceleration center axis throughout three sections. In addition, the electric field for efficient acceleration of electrons was generated in the resonance cavity by supplying microwave of 2.45 GHz.

Residential Interior Design as Complex Composition: A Case Study of a High School Senior's Composing Process

ERIC Educational Resources Information Center

Smagorinsky, Peter; Zoss, Michelle; Reed, Patty M.

2006-01-01

This research analyzed the composing processes of one high school student as she designed the interiors of homes for a course in interior design. Data included field notes, an interview with the teacher, artifacts from the class, and the focal student's concurrent and retrospective protocols in relation to her design of home interiors. The…

The order and priority of research and design method application within an assistive technology new product development process: a summative content analysis of 20 case studies.

PubMed

Torrens, George Edward

2018-01-01

Summative content analysis was used to define methods and heuristics from each case study. The review process was in two parts: (1) A literature review to identify conventional research methods and (2) a summative content analysis of published case studies, based on the identified methods and heuristics to suggest an order and priority of where and when were used. Over 200 research and design methods and design heuristics were identified. From the review of the 20 case studies 42 were identified as being applied. The majority of methods and heuristics were applied in phase two, market choice. There appeared a disparity between the limited numbers of methods frequently used, under 10 within the 20 case studies, when hundreds were available. Implications for Rehabilitation The communication highlights a number of issues that have implication for those involved in assistive technology new product development: •The study defined over 200 well-established research and design methods and design heuristics that are available for use by those who specify and design assistive technology products, which provide a comprehensive reference list for practitioners in the field; •The review within the study suggests only a limited number of research and design methods are regularly used by industrial design focused assistive technology new product developers; and, •Debate is required within the practitioners working in this field to reflect on how a wider range of potentially more effective methods and heuristics may be incorporated into daily working practice.

Dual-telescope multi-channel thermal-infrared radiometer for outer planet fly-by missions

NASA Astrophysics Data System (ADS)

Aslam, Shahid; Amato, Michael; Bowles, Neil; Calcutt, Simon; Hewagama, Tilak; Howard, Joseph; Howett, Carly; Hsieh, Wen-Ting; Hurford, Terry; Hurley, Jane; Irwin, Patrick; Jennings, Donald E.; Kessler, Ernst; Lakew, Brook; Loeffler, Mark; Mellon, Michael; Nicoletti, Anthony; Nixon, Conor A.; Putzig, Nathaniel; Quilligan, Gerard; Rathbun, Julie; Segura, Marcia; Spencer, John; Spitale, Joseph; West, Garrett

2016-11-01

The design of a versatile dual-telescope thermal-infrared radiometer spanning the spectral wavelength range 8-200 μm, in five spectral pass bands, for outer planet fly-by missions is described. The dual-telescope design switches between a narrow-field-of-view and a wide-field-of-view to provide optimal spatial resolution images within a range of spacecraft encounters to the target. The switchable dual-field-of-view system uses an optical configuration based on the axial rotation of a source-select mirror along the optical axis. The optical design, spectral performance, radiometric accuracy, and retrieval estimates of the instrument are discussed. This is followed by an assessment of the surface coverage performance at various spatial resolutions by using the planned NASA Europa Mission 13-F7 fly-by trajectories as a case study.

Dual-Telescope Multi-Channel Thermal-Infrared Radiometer for Outer Planet Fly-By Missions

NASA Technical Reports Server (NTRS)

Aslam, Shahid; Amato, Michael; Bowles, Neil; Calcutt, Simon; Hewagama, Tilak; Howard, Joseph; Howett, Carly; Hsieh, Wen-Ting; Hurford, Terry; Hurley, Jane;

Electrostatic focal spot correction for x-ray tubes operating in strong magnetic fields.

PubMed

Lillaney, Prasheel; Shin, Mihye; Hinshaw, Waldo; Fahrig, Rebecca

2014-11-01

A close proximity hybrid x-ray/magnetic resonance (XMR) imaging system offers several critical advantages over current XMR system installations that have large separation distances (∼5 m) between the imaging fields of view. The two imaging systems can be placed in close proximity to each other if an x-ray tube can be designed to be immune to the magnetic fringe fields outside of the MR bore. One of the major obstacles to robust x-ray tube design is correcting for the effects of the MR fringe field on the x-ray tube focal spot. Any fringe field component orthogonal to the x-ray tube electric field leads to electron drift altering the path of the electron trajectories. The method proposed in this study to correct for the electron drift utilizes an external electric field in the direction of the drift. The electric field is created using two electrodes that are positioned adjacent to the cathode. These electrodes are biased with positive and negative potential differences relative to the cathode. The design of the focusing cup assembly is constrained primarily by the strength of the MR fringe field and high voltage standoff distances between the anode, cathode, and the bias electrodes. From these constraints, a focusing cup design suitable for the close proximity XMR system geometry is derived, and a finite element model of this focusing cup geometry is simulated to demonstrate efficacy. A Monte Carlo simulation is performed to determine any effects of the modified focusing cup design on the output x-ray energy spectrum. An orthogonal fringe field magnitude of 65 mT can be compensated for using bias voltages of +15 and -20 kV. These bias voltages are not sufficient to completely correct for larger orthogonal field magnitudes. Using active shielding coils in combination with the bias electrodes provides complete correction at an orthogonal field magnitude of 88.1 mT. Introducing small fields (<10 mT) parallel to the x-ray tube electric field in addition to the orthogonal field does not affect the electrostatic correction technique. However, rotation of the x-ray tube by 30° toward the MR bore increases the parallel magnetic field magnitude (∼72 mT). The presence of this larger parallel field along with the orthogonal field leads to incomplete correction. Monte Carlo simulations demonstrate that the mean energy of the x-ray spectrum is not noticeably affected by the electrostatic correction, but the output flux is reduced by 7.5%. The maximum orthogonal magnetic field magnitude that can be compensated for using the proposed design is 65 mT. Larger orthogonal field magnitudes cannot be completely compensated for because a pure electrostatic approach is limited by the dielectric strength of the vacuum inside the x-ray tube insert. The electrostatic approach also suffers from limitations when there are strong magnetic fields in both the orthogonal and parallel directions because the electrons prefer to stay aligned with the parallel magnetic field. These challenging field conditions can be addressed by using a hybrid correction approach that utilizes both active shielding coils and biasing electrodes.

Electrostatic focal spot correction for x-ray tubes operating in strong magnetic fields

PubMed Central

Lillaney, Prasheel; Shin, Mihye; Hinshaw, Waldo; Fahrig, Rebecca

2014-01-01

Purpose: A close proximity hybrid x-ray/magnetic resonance (XMR) imaging system offers several critical advantages over current XMR system installations that have large separation distances (∼5 m) between the imaging fields of view. The two imaging systems can be placed in close proximity to each other if an x-ray tube can be designed to be immune to the magnetic fringe fields outside of the MR bore. One of the major obstacles to robust x-ray tube design is correcting for the effects of the MR fringe field on the x-ray tube focal spot. Any fringe field component orthogonal to the x-ray tube electric field leads to electron drift altering the path of the electron trajectories. Methods: The method proposed in this study to correct for the electron drift utilizes an external electric field in the direction of the drift. The electric field is created using two electrodes that are positioned adjacent to the cathode. These electrodes are biased with positive and negative potential differences relative to the cathode. The design of the focusing cup assembly is constrained primarily by the strength of the MR fringe field and high voltage standoff distances between the anode, cathode, and the bias electrodes. From these constraints, a focusing cup design suitable for the close proximity XMR system geometry is derived, and a finite element model of this focusing cup geometry is simulated to demonstrate efficacy. A Monte Carlo simulation is performed to determine any effects of the modified focusing cup design on the output x-ray energy spectrum. Results: An orthogonal fringe field magnitude of 65 mT can be compensated for using bias voltages of +15 and −20 kV. These bias voltages are not sufficient to completely correct for larger orthogonal field magnitudes. Using active shielding coils in combination with the bias electrodes provides complete correction at an orthogonal field magnitude of 88.1 mT. Introducing small fields (<10 mT) parallel to the x-ray tube electric field in addition to the orthogonal field does not affect the electrostatic correction technique. However, rotation of the x-ray tube by 30° toward the MR bore increases the parallel magnetic field magnitude (∼72 mT). The presence of this larger parallel field along with the orthogonal field leads to incomplete correction. Monte Carlo simulations demonstrate that the mean energy of the x-ray spectrum is not noticeably affected by the electrostatic correction, but the output flux is reduced by 7.5%. Conclusions: The maximum orthogonal magnetic field magnitude that can be compensated for using the proposed design is 65 mT. Larger orthogonal field magnitudes cannot be completely compensated for because a pure electrostatic approach is limited by the dielectric strength of the vacuum inside the x-ray tube insert. The electrostatic approach also suffers from limitations when there are strong magnetic fields in both the orthogonal and parallel directions because the electrons prefer to stay aligned with the parallel magnetic field. These challenging field conditions can be addressed by using a hybrid correction approach that utilizes both active shielding coils and biasing electrodes. PMID:25370658

Initial Field Testing for Forest Tree Improvement

Treesearch

C. B. Briscoe

1963-01-01

Initial field testing for forest tree improvement is essentially a comparison of genetic groups whether the level of comparison is of species, provenances, or individual trees. A good study design should be as economical as possible, for a given precision, and must be accurate. The latter is simply obtained by restricting the study to a specified set of conditions,...

A Guide to Field Studies for the Coastal Environment. Project CAPE Teaching Module.

ERIC Educational Resources Information Center

Barker, Wells J.

Twenty-five coastal field study investigations, comprising this supplement to a junior high school earth science curriculum, are designed to help students obtain a fuller understanding of: (1) their coastal environment, (2) some of the problems which confront it, (3) the interrelationships between the land and the surrounding bodies of water, and…

Curriculum Package: High School Social Studies Lessons. [A Visit to the Louisville, Kentucky Airports: Standiford and Bowman Fields.

ERIC Educational Resources Information Center

DeSensi, Frank; Rostov, Susan

These lesson plans are designed for use by high school social studies teachers who take their students on a field trip to the regional airports of Louisville, Kentucky. Twelve lesson plans are included: "It's the Computer's Fault"; "The Play's the Thing"; "A Hub! Yes, There's the Rub!"; "People and…

Teaching Statistical Inference for Causal Effects in Experiments and Observational Studies

ERIC Educational Resources Information Center

Rubin, Donald B.

2004-01-01

Inference for causal effects is a critical activity in many branches of science and public policy. The field of statistics is the one field most suited to address such problems, whether from designed experiments or observational studies. Consequently, it is arguably essential that departments of statistics teach courses in causal inference to both…

Effects of Field Instructor Training on Student Competencies and the Supervisory Alliance

ERIC Educational Resources Information Center

Deal, Kathleen Holtz; Bennett, Susanne; Mohr, Jonathan; Hwang, Jeongha

2011-01-01

Objectives: This study of a field instructor (FI) training model, offered at two universities, focused on the relationship between student competencies, the supervisory alliance, and students' attachment styles. Method: The study used a pretest-posttest follow-up design of 100 randomly assigned FIs (training group = 48; control group = 52) and 64…

Field investigation of high performance pavements in Virginia.

DOT National Transportation Integrated Search

2005-01-01

This study evaluated 18 pavement sections located in high-traffic highways in Virginia to find a premium pavement design with a life span of 40 years or more using current and past field experience. The selected pavement sections were thought to perf...

Inhibition of brain tumor cell proliferation by alternating electric fields

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jeong, Hyesun; Oh, Seung-ick; Hong, Sunghoi, E-mail: shong21@korea.ac.kr, E-mail: radioyoon@korea.ac.kr

2014-11-17

This study was designed to investigate the mechanism by which electric fields affect cell function, and to determine the optimal conditions for electric field inhibition of cancer cell proliferation. Low-intensity (<2 V/cm) and intermediate-frequency (100–300 kHz) alternating electric fields were applied to glioblastoma cell lines. These electric fields inhibited cell proliferation by inducing cell cycle arrest and abnormal mitosis due to the malformation of microtubules. These effects were significantly dependent on the intensity and frequency of applied electric fields.

Towards an electro-magnetic field separation of deposited material implemented in an ion beam sputter process

DOE Office of Scientific and Technical Information (OSTI.GOV)

Malobabic, Sina; Jupe, Marco; Ristau, Detlev

Nowadays, Ion Beam Sputter (IBS) processes are very well optimized on an empirical basis. To achieve further progresses, a modification of the IBS process by guiding the coating material using an axial magnetic field and an additional electrical field has been studied. The electro-magnetic (EM) field leads to a significant change in plasma properties and deposition rate distributions, whereas an increase in deposition rate along the centerline of the axial EM field around 150% was observed. These fundamental studies on the prototype are the basis for the development of an applicable and workable design of a separation device.

Usability Testing with Online Research Panels: A Case Study from the Field of Instructional Design

ERIC Educational Resources Information Center

Williams Van Rooij, Shahron

2013-01-01

One of the challenges experienced by students of instructional design is eliciting user participation when designing and developing products for course or program projects, particularly over multiple cycles of evaluation. Student projects do not normally have budgets to engage recruitment companies or provide participant incentives. This paper…

The Engineering Design Process: Conceptions along the Learning-To-Teach Continuum

ERIC Educational Resources Information Center

Iveland, Ashley

2017-01-01

In this study, I sought to identify differences in the views and understandings of engineering design among individuals along the learning-to-teach continuum. To do so, I conducted a comprehensive review of literature to determine the various aspects of engineering design described in the fields of professional engineering and engineering…

The Roles of Technical Communication Researchers in Design Scholarship

ERIC Educational Resources Information Center

Sánchez, Fernando

2017-01-01

Design has come to be understood as an essential aspect of the work that technical communicators claim. As a result, research in the field of technical communication has approached studies of design in numerous ways. This article showcases how technical communication researchers assume the roles of observers, testers, critics, creators, and…

Learning Design: Requirements, Practice and Prospects

ERIC Educational Resources Information Center

MacLean, Piers; Scott, Bernard

2007-01-01

Purpose: The purpose of this paper is to describe research into the requirements, practice and prospects for the field of learning design and provide the findings of this study to date alongside early recommendations for furthering the profession in the UK. Design/methodology/approach: The paper describes the findings of a review of the literature…

A generalized algorithm to design finite field normal basis multipliers

NASA Technical Reports Server (NTRS)

Wang, C. C.

1986-01-01

Finite field arithmetic logic is central in the implementation of some error-correcting coders and some cryptographic devices. There is a need for good multiplication algorithms which can be easily realized. Massey and Omura recently developed a new multiplication algorithm for finite fields based on a normal basis representation. Using the normal basis representation, the design of the finite field multiplier is simple and regular. The fundamental design of the Massey-Omura multiplier is based on a design of a product function. In this article, a generalized algorithm to locate a normal basis in a field is first presented. Using this normal basis, an algorithm to construct the product function is then developed. This design does not depend on particular characteristics of the generator polynomial of the field.

TU-H-BRA-05: A System Design for Integration of An Interior MRI and a Linear Accelerator

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mao, W; Henry Ford Hospital, Detroit, MI; Wang, G

Purpose: MRI is a highly desirable modality to guide radiation therapy but it is difficult to combine a conventional MRI scanner directly with a linear accelerator (linac). An interior MRI (iMRI) concept has been proposed to acquire MRI images within a small field of view only covering targets and immediate surrounding tissues. The objective of this project is to design an interior MRI system to work with a linac using a magnet to provide a field around 0.2T in a cube of 20cm per side, and perform image reconstruction with a slightly inhomogeneous static magnetic fields. Methods: All the resultsmore » are simulated using a commercially available software package, FARADY. In our design, a ring structure holds the iMRI system and also imbeds a linac treatment head. The ring is synchronized to the linac gantry rotation. Half of the ring is made of steel and becomes a magnetic flux return path (yoke) so that a strong magnetic field will be limited inside the iron circuit and fringe fields will be very weak. In order to increase the static magnetic field homogeneity, special steel magnet boots or tips were simulated. Three curved boots were designed based on two-dimensional curves: arc, parabola and hyperbola. Results: Different boot surfaces modify magnetic field distributions differently. With the same pair of neodymium-iron-boron (NdFeB) magnets, the magnetic induction at the centers are 0.217T, 0.201T, 0.204T, and 0.212T for flat, arc, parabola and hyperbola boots, respectively. The hyperbola boots lead to the most homogeneous results, the static magnetic field deviations are within 0.5% in a cube of 20cm, and can be further improved using shimming techniques. Conclusion: This study supports the concept of an iMRI design. Successful development of iMRI will provide crucial information for tumor delineation in radiation therapy.« less

Measurements of the Basic SR-71 Airplane Near-Field Signature

NASA Technical Reports Server (NTRS)

Haering, Edward A., Jr.; Whitmore, Stephen A.; Ehernberger, L. J.

1999-01-01

Airplane design studies have developed configuration concepts that may produce lower sonic boom annoyance levels. Since lower noise designs differ significantly from other HSCT designs, it is necessary to accurately assess their potential before HSCT final configuration decisions are made. Flight tests to demonstrate lower noise design capability by modifying an existing airframe have been proposed for the Mach 3 SR-71 reconnaissance airplane. To support the modified SR-71 proposal, baseline in-flight measurements were made of the unmodified aircraft. These measurements of SR-71 near-field sonic boom signatures were obtained by an F-16XL probe airplane at flightpath separation distances ranging from approximately 740 to 40 ft. This paper discusses the methods used to gather and analyze the flight data, and makes comparisons of these flight data with CFD results from Douglas Aircraft Corporation and NASA Langley Research Center. The CFD solutions were obtained for the near-field flow about the SR-71, and then propagated to the flight test measurement location using the program MDBOOM.

Optimal Bayesian Adaptive Design for Test-Item Calibration.

PubMed

van der Linden, Wim J; Ren, Hao

2015-06-01

An optimal adaptive design for test-item calibration based on Bayesian optimality criteria is presented. The design adapts the choice of field-test items to the examinees taking an operational adaptive test using both the information in the posterior distributions of their ability parameters and the current posterior distributions of the field-test parameters. Different criteria of optimality based on the two types of posterior distributions are possible. The design can be implemented using an MCMC scheme with alternating stages of sampling from the posterior distributions of the test takers' ability parameters and the parameters of the field-test items while reusing samples from earlier posterior distributions of the other parameters. Results from a simulation study demonstrated the feasibility of the proposed MCMC implementation for operational item calibration. A comparison of performances for different optimality criteria showed faster calibration of substantial numbers of items for the criterion of D-optimality relative to A-optimality, a special case of c-optimality, and random assignment of items to the test takers.

Optical Design for a Survey X-Ray Telescope

NASA Technical Reports Server (NTRS)

Saha, Timo T.; Zhang, William W.; McClelland, Ryan S.

2014-01-01

Optical design trades are underway at the Goddard Space Flight Center to define a telescope for an x-ray survey mission. Top-level science objectives of the mission include the study of x-ray transients, surveying and long-term monitoring of compact objects in nearby galaxies, as well as both deep and wide-field x-ray surveys. In this paper we consider Wolter, Wolter-Schwarzschild, and modified Wolter-Schwarzschild telescope designs as basic building blocks for the tightly nested survey telescope. Design principles and dominating aberrations of individual telescopes and nested telescopes are discussed and we compare the off-axis optical performance at 1.0 KeV and 4.0 KeV across a 1.0-degree full field-of-view.

The personnel economics approach to public workforce research.

PubMed

Gibbs, Michael

2009-11-01

This article argues that the relatively new field of personnel economics (PE) holds strong potential as a tool for studying public sector workforces. This subfield of labor economics is based on a strong foundation of microeconomics, which provides a robust theoretical foundation for studying workforce and organizational design issues. PE has evolved on this foundation to a strong practical emphasis, with theoretical insights designed for practical use and with strong focus on empirical research. The field is also characterized by creative data entrepreneurship. The types of datasets that personnel economists use are described. If similar datasets can be obtained for public sector workforces, PE should be a very useful approach for studying them.

Using experimental design and spatial analyses to improve the precision of NDVI estimates in upland cotton field trials

USDA-ARS?s Scientific Manuscript database

Controlling for spatial variability is important in high-throughput phenotyping studies that enable large numbers of genotypes to be evaluated across time and space. In the current study, we compared the efficacy of different experimental designs and spatial models in the analysis of canopy spectral...

Design Criteria for Learning and Teaching Genetics

ERIC Educational Resources Information Center

Knippels, Marie-Christine P. J.; Waarlo, Arend Jan; Boersma, Kerst Th.

2005-01-01

While learning and teaching difficulties in genetics have been abundantly explored and described, there has been less focus on the development and field-testing of strategies to address them. To inform the design of such a strategy a review study, focus group interviews with teachers, a case study of a traditional series of genetics lessons,…

Mobile application for field data collection and query: Example from wildlife research (Invited)

NASA Astrophysics Data System (ADS)

Bateman, H.; Lindquist, T.; Whitehouse, R.

2013-12-01

Field data collection is often used in many scientific disciplines and effective approaches rely on accurate data collection and recording. We designed a smartphone and tablet application (app) for field-collected data and tested it during a study on wildlife. The objective of our study was to determine the effectiveness of mobile applications in wildlife field research. Student software developers designed applications for mobile devices on the iOS and Android operating systems. Both platforms had similar user interactions via data entry on a touch screen using pre-programmed fields, checkboxes, drop-down menus, and keypad entry. The mobile application included features to insure collection of all measurements in the field through pop-up messages and could proof entries for valid formats. We used undergraduate student subjects to compare the duration of data recording and data entry, and the frequency of errors between the mobile application and traditional (paper) techniques. We field-tested the mobile application using an existing study on wildlife. From the field, technicians could query a database stored on a mobile device to view histories of previously captured animals. Overall, we found that because the mobile application allowed us to enter data in a digital format in the field we could eliminate timely steps to process handwritten data sheets and double-checking data entries. We estimated that, for a 2-month project, using the mobile application instead of traditional data entry and proofing reduced our total project time by 10%. To our knowledge, this is the first application developed for mobile devices for wildlife users interesting in viewing animal capture histories from the field and could be developed for use in other areas of field research.

Topology optimized gold nanostrips for enhanced near-infrared photon upconversion

NASA Astrophysics Data System (ADS)

Vester-Petersen, Joakim; Christiansen, Rasmus E.; Julsgaard, Brian; Balling, Peter; Sigmund, Ole; Madsen, Søren P.

2017-09-01

This letter presents a topology optimization study of metal nanostructures optimized for electric-field enhancement in the infrared spectrum. Coupling of such nanostructures with suitable ions allows for an increased photon-upconversion yield, with one application being an increased solar-cell efficiency by exploiting the long-wavelength part of the solar spectrum. In this work, topology optimization is used to design a periodic array of two-dimensional gold nanostrips for electric-field enhancements in a thin film doped with upconverting erbium ions. The infrared absorption band of erbium is utilized by simultaneously optimizing for two polarizations, up to three wavelengths, and three incident angles. Geometric robustness towards manufacturing variations is implemented considering three different design realizations simultaneously in the optimization. The polarization-averaged field enhancement for each design is evaluated over an 80 nm wavelength range and a ±15-degree incident angle span. The highest polarization-averaged field enhancement is 42.2 varying by maximally 2% under ±5 nm near-uniform design perturbations at three different wavelengths (1480 nm, 1520 nm, and 1560 nm). The proposed method is generally applicable to many optical systems and is therefore not limited to enhancing photon upconversion.

Design of a conduction-cooled 4 T superconducting racetrack for a multi-field coupling measurement system

NASA Astrophysics Data System (ADS)

Chen, Yu-Quan; Ma, Li-Zhen; Wu, Wei; Guan, Ming-Zhi; Wu, Bei-Min; Mei, En-Ming; Xin, Can-Jie

2015-12-01

A conduction-cooled superconducting magnet producing a transverse field of 4 T has been designed for a new generation multi-field coupling measurement system, which will be used to study the mechanical behavior of superconducting samples at cryogenic temperatures and intense magnetic fields. A compact cryostat with a two-stage GM cryocooler is designed and manufactured for the superconducting magnet. The magnet is composed of a pair of flat racetrack coils wound by NbTi/Cu superconducting composite wires, a copper and stainless steel combinational former and two Bi2Sr2CaCu2Oy superconducting current leads. The two coils are connected in series and can be powered with a single power supply. In order to support the high stress and attain uniform thermal distribution in the superconducting magnet, a detailed finite element (FE) analysis has been performed. The results indicate that in the operating status the designed magnet system can sufficiently bear the electromagnetic forces and has a uniform temperature distribution. Supported by National Natural Science Foundation of China (11327802, 11302225), China Postdoctoral Science Foundation (2014M560820) and National Scholarship Foundation of China (201404910172)

Design and field test of collaborative tools in the service of an innovative organization

DOE Office of Scientific and Technical Information (OSTI.GOV)

De Beler, N.; Parfouru, S.

2012-07-01

This paper presents the design process of collaborative tools, based on ICT, aiming at supporting the tasks of the team that manages an outage of an energy production plant for maintenance activities. The design process follows an iterative and multidisciplinary approach, based on a collective tasks modeling of the outage management team in the light of Socio Organizational and Human (SOH) field studies, and on the state of the art of ICT. Field test of the collaborative tools designed plays a great place in this approach, allowing taking into account the operational world but involves also some risks which mustmore » be managed. To implement tools on all the production plants, we build an 'operational concept' with a level of description which authorizes the evolution of tools and allows some local adaptations. The field tests provide lessons on the ICT topics. For examples: the status of the remote access tools, the potential of use of a given information input by an actor for several individual and collective purposes, the actors perception of the tools meaning, and the requirements for supporting the implementation of change. (authors)« less

Production optimization of sucker rod pumping wells producing viscous oil in Boscan field, Venezuela

DOE Office of Scientific and Technical Information (OSTI.GOV)

Guirados, C.; Sandoval, J.; Rivas, O.

1995-12-31

Boscan field is located in the western coast of Maracaibo lake and is operated by Maraven S.A., affiliate of Petroleos de Venezuela S.A. It has 315 active wells, 252 of which are produced with sucker rod pumping. Other artificial lift methods currently applied in this field are hydraulic (piston) pumping (39 wells) and ESP (24 wells). This paper presents the results of the production optimization of two sucker rod pumping wells of Boscan field producing viscous oil. This optimization has been possible due to the development of a new production scheme and the application of system analysis in completion design.more » The new production scheme involves the utilization of a subsurface stuffing box assembly and a slotted housing, both designed and patented by Intevep S.A., affiliate of Petroleos de Venezuela S.A. The completion design method and software used in the optimization study were also developed by Intevep S.A. The new production scheme and design method proved to be effective in preventing the causes of the above mentioned problems, allowing the increase of oil production under better operating conditions.« less

Geotechnical Field Data and Analysis Report, July 1991--June 1992. Volume 1

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1993-09-01

The Geotechnical Field Data and Analysis Report documents the geotechnical data from the underground excavations at the Waste Isolation Pilot Plant (WIPP) located near Carlsbad, New Mexico. The data are used to characterize conditions, confirm design assumptions, and understand and predict the performance of the underground excavations during operations. The data are obtained as part of a routine monitoring program and do not include data from tests performed by Sandia National Laboratories (SNL), the Scientific Advisor to the project, in support of performance assessment studies. The purpose of the geomechanical monitoring program is to provide in situ data to supportmore » continuing assessments of the design for the underground facilities. Specifically, the program provides: Early detection of conditions that could compromise operational safety; evaluation of room closure to ensure retrievability of waste; guidance for design modifications and remedial actions; and data for interpreting the actual behavior of underground openings, in comparison with established design criteria. This Geotechnical Field Data and Analysis Report covers the period July 1, 1991 to June 30, 1992. Volume 1 provides an interpretation of the field data while Volume 2 describes and presents the data itself.« less

Investigation on the optimal magnetic field of a cusp electron gun for a W-band gyro-TWA

NASA Astrophysics Data System (ADS)

Zhang, Liang; He, Wenlong; Donaldson, Craig R.; Cross, Adrian W.

2018-05-01

High efficiency and broadband operation of a gyrotron traveling wave amplifier (gyro-TWA) require a high-quality electron beam with low-velocity spreads. The beam velocity spreads are mainly due to the differences of the electric and magnetic fields that the electrons withstand the electron gun. This paper investigates the possibility to decouple the design of electron gun geometry and the magnet system while still achieving optimal results, through a case study of designing a cusp electron gun for a W-band gyro-TWA. A global multiple-objective optimization routing was used to optimize the electron gun geometry for different predefined magnetic field profiles individually. Their results were compared and the properties of the required magnetic field profile are summarized.

Light field otoscope design for 3D in vivo imaging of the middle ear

PubMed Central

Bedard, Noah; Shope, Timothy; Hoberman, Alejandro; Haralam, Mary Ann; Shaikh, Nader; Kovačević, Jelena; Balram, Nikhil; Tošić, Ivana

2016-01-01

We present a light field digital otoscope designed to measure three-dimensional shape of the tympanic membrane. This paper describes the optical and anatomical considerations we used to develop the prototype, along with the simulation and experimental measurements of vignetting, field curvature, and lateral resolution. Using an experimental evaluation procedure, we have determined depth accuracy and depth precision of our system to be 0.05–0.07 mm and 0.21–0.44 mm, respectively. To demonstrate the application of our light field otoscope, we present the first three-dimensional reconstructions of tympanic membranes in normal and otitis media conditions, acquired from children who participated in a feasibility study at the Children’s Hospital of Pittsburgh of the University of Pittsburgh Medical Center. PMID:28101416

Stiffness control of magnetorheological gels for adaptive tunable vibration absorber

NASA Astrophysics Data System (ADS)

Kim, Hyun Kee; Kim, Hye Shin; Kim, Young-Keun

2017-01-01

In this study, a stiffness feedback control system for magnetorheological (MR) gel—a smart material of variable stiffness—is proposed, toward the design of a tunable vibration absorber that can adaptively tune to a time varying disturbance in real time. A PID controller was designed to track the required stiffness of the MR gel by controlling the magnitude of the target external magnetic field pervading the MR gel. This paper proposes a novel magnetic field generator that could produce a variable magnetic field with low energy consumption. The performance of the MR gel stiffness control was validated through experiments that showed the MR gel absorber system could be automatically tuned from 56 Hz to 67 Hz under a field of 100 mT to minimize the vibration of the primary system.

Design and fabrication of novel anode flow-field for commercial size solid oxide fuel cells

NASA Astrophysics Data System (ADS)

Canavar, Murat; Timurkutluk, Bora

2017-04-01

In this study, nickel based woven meshes are tested as not only anode current collecting meshes but also anode flow fields instead of the conventional gas channels fabricated by machining. For this purpose, short stacks with different anode flow fields are designed and built by using different number of meshes with various wire diameters and widths of opening. A short stack with classical machined flow channels is also constructed. Performance and impedance measurements of the short stacks with commercial size cells of 81 cm2 active area are performed and compared. The results reveal that it is possible to create solid oxide fuel cell anode flow fields with woven meshes and obtain acceptable power with a proper selection of the mesh number, type and orientation.

Simulation analysis of rectifying microfluidic mixing with field-effect-tunable electrothermal induced flow.

PubMed

Liu, Weiyu; Ren, Yukun; Tao, Ye; Yao, Bobin; Li, You

2018-03-01

We report herein field-effect control on in-phase electrothermal streaming from a theoretical point of view, a phenomenon termed "alternating-current electrothermal-flow field effect transistor" (ACET-FFET), in the context of a new technology for handing analytes in microfluidics. Field-effect control through a gate terminal endows ACET-FFET the ability to generate arbitrary symmetry breaking in the transverse vortex flow pattern, which makes it attractive for mixing microfluidic samples. A computational model is developed to study the feasibility of this new microfluidic device design for micromixing. The influence of various parameters on developing an efficient mixer is investigated, and an integrated layout of discrete electrode array is suggested for achieving high-throughput mixing. Our physical demonstration with field-effect electrothermal flow control using a simple electrode structure proves invaluable for designing active micromixers for modern micro total analytical system. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Study of the Insulating Magnetic Field in an Accelerating Ion Diode

NASA Astrophysics Data System (ADS)

Kozlovsky, K. I.; Martynenko, A. S.; Vovchenko, E. D.; Lisovsky, M. I.; Isaev, A. A.

2017-12-01

The results of examination of the insulating magnetic field in an accelerating ion diode are presented. This field is produced in order to suppress the electron current and thus enhance the neutron yield of the D( d, n)3He nuclear reaction. The following two designs are discussed: a gas-filled diode with inertial electrostatic confinement of ions and a vacuum diode with a laser-plasma ion source and pulsed magnetic insulation. Although the insulating field of permanent magnets is highly nonuniform, it made it possible to extend the range of accelerating voltages to U = 200 kV and raise the neutron yield to Q = 107 in the first design. The nonuniform field structure is less prominent in the device with pulsed magnetic insulation, which demonstrated efficient deuteron acceleration with currents up to 1 kA at U = 400 kV. The predicted neutron yield is as high as 109 neutrons/pulse.

Langmuir probe measurements in the intense RF field of a helicon discharge

NASA Astrophysics Data System (ADS)

Chen, Francis F.

2012-10-01

Helicon discharges have extensively been studied for over 25 years both because of their intriguing physics and because of their utility in producing high plasma densities for industrial applications. Almost all measurements so far have been made away from the antenna region in the plasma ejected into a chamber where there may be a strong magnetic field (B-field) but where the radiofrequency (RF) field is much weaker than under the antenna. Inside the source region, the RF field distorts the current-voltage (I-V) characteristic of the probe unless it is specially designed with strong RF compensation. For this purpose, a thin probe was designed and used to show the effect of inadequate compensation on electron temperature (Te) measurements. The subtraction of ion current from the I-V curve is essential; and, surprisingly, Langmuir's orbital motion limited theory for ion current can be used well beyond its intended regime.

Numerical analysis of magnetic field in superconducting magnetic energy storage

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kanamaru, Y.; Amemiya, Y.

1991-09-01

This paper reports that the superconducting magnetic energy storage (SMES) is more useful than the other systems of electric energy storage because of larger stored energy and higher efficiency. The other systems are the battery, the flywheel, the pumped-storage power station. Some models of solenoid type SMES are designed in U.S.A. and Japan. But a high magnetic field happens by the large scale SMES in the living environment, and makes the erroneous operations of the computer display, the pacemaker of the heart and the electronic equipments. We study some fit designs of magnetic shielding of the solenoidal type SMES formore » reduction of the magnetic field in living environment. When some superconducting shielding coils are over the main storage coil, magnetic field reduces remarkably than the case of non shielding coil. The calculated results of the magnetic field are obtained y the finite element method.« less

Design of an 81.25 MHz continuous-wave radio-frequency quadrupole accelerator for Low Energy Accelerator Facility

NASA Astrophysics Data System (ADS)

Ma, Wei; Lu, Liang; Xu, Xianbo; Sun, Liepeng; Zhang, Zhouli; Dou, Weiping; Li, Chenxing; Shi, Longbo; He, Yuan; Zhao, Hongwei

2017-03-01

An 81.25 MHz continuous wave (CW) radio frequency quadrupole (RFQ) accelerator has been designed for the Low Energy Accelerator Facility (LEAF) at the Institute of Modern Physics (IMP) of the Chinese Academy of Science (CAS). In the CW operating mode, the proposed RFQ design adopted the conventional four-vane structure. The main design goals are providing high shunt impendence with low power losses. In the electromagnetic (EM) design, the π-mode stabilizing loops (PISLs) were optimized to produce a good mode separation. The tuners were also designed and optimized to tune the frequency and field flatness of the operating mode. The vane undercuts were optimized to provide a flat field along the RFQ cavity. Additionally, a full length model with modulations was set up for the final EM simulations. Following the EM design, thermal analysis of the structure was carried out. In this paper, detailed EM design and thermal simulations of the LEAF-RFQ will be presented and discussed. Structure error analysis was also studied.

A ligand-based comparative molecular field analysis (CoMFA) and homology model based molecular docking studies on 3', 4'-dihydroxyflavones as rat 5-lipoxygenase inhibitors: Design of new inhibitors.

PubMed

Ahamed, T K Shameera; Muraleedharan, K

2017-12-01

In this study, ligand based comparative molecular field analysis (CoMFA) with five principal components was performed on class of 3', 4'-dihydroxyflavone derivatives for potent rat 5-LOX inhibitors. The percentage contributions in building of CoMFA model were 91.36% for steric field and 8.6% for electrostatic field. R 2 values for training and test sets were found to be 0.9320 and 0.8259, respectively. In case of LOO, LTO and LMO cross validation test, q 2 values were 0.6587, 0.6479 and 0.5547, respectively. These results indicate that the model has high statistical reliability and good predictive power. The extracted contour maps were used to identify the important regions where the modification was necessary to design a new molecule with improved activity. The study has developed a homology model for rat 5-LOX and recognized the key residues at the binding site. Docking of most active molecule to the binding site of 5-LOX confirmed the stability and rationality of CoMFA model. Based on molecular docking results and CoMFA contour plots, new inhibitors with higher activity with respect to the most active compound in data set were designed. Copyright © 2017 Elsevier Ltd. All rights reserved.

Contending Claims to Causality: A Critical Review of Mediation Research in HRD

ERIC Educational Resources Information Center

Ghosh, Rajashi; Jacobson, Seth

2016-01-01

Purpose: The purpose of this paper is to conduct a critical review of the mediation studies published in the field of Human Resource Development (HRD) to discern if the study designs, the nature of data collection and the choice of statistical methods justify the causal claims made in those studies. Design/methodology/approach: This paper conducts…

Toward Development of a Stochastic Wake Model: Validation Using LES and Turbine Loads

DOE PAGES

Moon, Jae; Manuel, Lance; Churchfield, Matthew; ...

2017-12-28

Wind turbines within an array do not experience free-stream undisturbed flow fields. Rather, the flow fields on internal turbines are influenced by wakes generated by upwind unit and exhibit different dynamic characteristics relative to the free stream. The International Electrotechnical Commission (IEC) standard 61400-1 for the design of wind turbines only considers a deterministic wake model for the design of a wind plant. This study is focused on the development of a stochastic model for waked wind fields. First, high-fidelity physics-based waked wind velocity fields are generated using Large-Eddy Simulation (LES). Stochastic characteristics of these LES waked wind velocity field,more » including mean and turbulence components, are analyzed. Wake-related mean and turbulence field-related parameters are then estimated for use with a stochastic model, using Multivariate Multiple Linear Regression (MMLR) with the LES data. To validate the simulated wind fields based on the stochastic model, wind turbine tower and blade loads are generated using aeroelastic simulation for utility-scale wind turbine models and compared with those based directly on the LES inflow. The study's overall objective is to offer efficient and validated stochastic approaches that are computationally tractable for assessing the performance and loads of turbines operating in wakes.« less

Toward Development of a Stochastic Wake Model: Validation Using LES and Turbine Loads

DOE Office of Scientific and Technical Information (OSTI.GOV)

Moon, Jae; Manuel, Lance; Churchfield, Matthew

Wind turbines within an array do not experience free-stream undisturbed flow fields. Rather, the flow fields on internal turbines are influenced by wakes generated by upwind unit and exhibit different dynamic characteristics relative to the free stream. The International Electrotechnical Commission (IEC) standard 61400-1 for the design of wind turbines only considers a deterministic wake model for the design of a wind plant. This study is focused on the development of a stochastic model for waked wind fields. First, high-fidelity physics-based waked wind velocity fields are generated using Large-Eddy Simulation (LES). Stochastic characteristics of these LES waked wind velocity field,more » including mean and turbulence components, are analyzed. Wake-related mean and turbulence field-related parameters are then estimated for use with a stochastic model, using Multivariate Multiple Linear Regression (MMLR) with the LES data. To validate the simulated wind fields based on the stochastic model, wind turbine tower and blade loads are generated using aeroelastic simulation for utility-scale wind turbine models and compared with those based directly on the LES inflow. The study's overall objective is to offer efficient and validated stochastic approaches that are computationally tractable for assessing the performance and loads of turbines operating in wakes.« less

Structural basis of orientation sensitivity of cat retinal ganglion cells.

PubMed

Leventhal, A G; Schall, J D

1983-11-10

We investigated the structural basis of the physiological orientation sensitivity of retinal ganglion cells (Levick and Thibos, '82). The dendritic fields of 840 retinal ganglion cells labeled by injections of horseradish peroxidase into the dorsal lateral geniculate nucleus (LGNd) or optic tracts of normal cats. Siamese cats, and cat deprived of patterned visual experience from birth by monocular lid-suture (MD) were studied. Mathematical techniques designed to analyze direction were used to find the dendritic field orientation of each cell. Statistical techniques designed for angular data were used to determine the relationship between dendritic field orientation and angular position on the retina (polar angle). Our results indicate that 88% of retinal ganglion cells have oriented dendritic fields and that dendritic field orientation is related systematically to retinal position. In all regions of retina more that 0.5 mm from the area centralis the dendritic fields of retinal ganglion cells are oriented radially, i.e., like the spokes of a wheel having the area centralis at its hub. This relationship was present in all animals and cell types studied and was strongest for cells located close to the horizontal meridian (visual streak) of the retina. Retinal ganglion cells appear to be sensitive to stimulus orientation because they have oriented dendritic fields.

The importance of aerodynamics for prosthetic limb design used by competitive cyclists with an amputation: An introduction.

PubMed

Dyer, Bryce

2015-06-01

This study introduces the importance of the aerodynamics to prosthetic limb design for athletes with either a lower-limb or upper-limb amputation. The study comprises two elements: 1) An initial experiment investigating the stability of outdoor velodrome-based field tests, and 2) An experiment evaluating the application of outdoor velodrome aerodynamic field tests to detect small-scale changes in aerodynamic drag respective of prosthetic limb componentry changes. An outdoor field-testing method is used to detect small and repeatable changes in the aerodynamic drag of an able-bodied cyclist. These changes were made at levels typical of alterations in prosthetic componentry. The field-based test method of assessment is used at a smaller level of resolution than previously reported. With a carefully applied protocol, the field test method proved to be statistically stable. The results of the field test experiments demonstrate a noticeable change in overall athlete performance. Aerodynamic refinement of artificial limbs is worthwhile for athletes looking to maximise their competitive performance. A field-testing method illustrates the importance of the aerodynamic optimisation of prosthetic limb components. The field-testing protocol undertaken in this study gives an accessible and affordable means of doing so by prosthetists and sports engineers. Using simple and accessible field-testing methods, this exploratory experiment demonstrates how small changes to riders' equipment, consummate of the scale of a small change in prosthetics componentry, can affect the performance of an athlete. Prosthetists should consider such opportunities for performance enhancement when possible. © The International Society for Prosthetics and Orthotics 2014.

Field Water Balance of Landfill Final Covers

EPA Science Inventory

Landfill covers are critical to waste containment, yet field performance of specific cover designs has not been well documented and seldom been compared in side-by-side testing. A study was conducted to assess the ability of landfill final covers to control percolation into unde...

General design method for three-dimensional potential flow fields. 1: Theory

NASA Technical Reports Server (NTRS)

Stanitz, J. D.

1980-01-01

A general design method was developed for steady, three dimensional, potential, incompressible or subsonic-compressible flow. In this design method, the flow field, including the shape of its boundary, was determined for arbitrarily specified, continuous distributions of velocity as a function of arc length along the boundary streamlines. The method applied to the design of both internal and external flow fields, including, in both cases, fields with planar symmetry. The analytic problems associated with stagnation points, closure of bodies in external flow fields, and prediction of turning angles in three dimensional ducts were reviewed.

Modeling and simulation of flow field in giant magnetostrictive pump

NASA Astrophysics Data System (ADS)

Zhao, Yapeng; Ren, Shiyong; Lu, Quanguo

2017-09-01

Recent years, there has been significant research in the design and analysis of giant magnetostrictive pump. In this paper, the flow field model of giant magnetostrictive pump was established and the relationship between pressure loss and working frequency of piston was studied by numerical simulation method. Then, the influence of different pump chamber height on pressure loss in giant magnetostrictive pump was studied by means of flow field simulation. Finally, the fluid pressure and velocity vector distribution in giant magnetostrictive pump chamber were simulated.

Science in the Wild: Technology Needs and Opportunities in Scientific Fieldwork

NASA Technical Reports Server (NTRS)

Guice, Jon; Hoffower, Heidi; Norvig, Peter (Technical Monitor)

1999-01-01

Considering that much contemporary natural science involves field expeditions, fieldwork is an under-studied topic. There is also little information technology specifically designed to support scientific fieldwork, aside from portable scientific instruments. This article describes a variety of fieldwork practices in an interdisciplinary research area, proposes a framework linking types of fieldwork to types of needs in information technology, and identifies promising opportunities for technology development. Technologies that are designed to support the integration of field observations and samples with laboratory work are likely to aid nearly all research teams who conduct fieldwork. However, technologies that support highly detailed representations of field sites will likely trigger the deepest changes in work practice. By way of illustration, we present brief case studies of how fieldwork is done today and how it might be conducted with the introduction of new information technologies.

Conducting field studies for testing pesticide leaching models

USGS Publications Warehouse

Smith, Charles N.; Parrish, Rudolph S.; Brown, David S.

1990-01-01

A variety of predictive models are being applied to evaluate the transport and transformation of pesticides in the environment. These include well known models such as the Pesticide Root Zone Model (PRZM), the Risk of Unsaturated-Saturated Transport and Transformation Interactions for Chemical Concentrations Model (RUSTIC) and the Groundwater Loading Effects of Agricultural Management Systems Model (GLEAMS). The potentially large impacts of using these models as tools for developing pesticide management strategies and regulatory decisions necessitates development of sound model validation protocols. This paper offers guidance on many of the theoretical and practical problems encountered in the design and implementation of field-scale model validation studies. Recommendations are provided for site selection and characterization, test compound selection, data needs, measurement techniques, statistical design considerations and sampling techniques. A strategy is provided for quantitatively testing models using field measurements.

Ergonomic design in ancient Greece.

PubMed

Marmaras, N; Poulakakis, G; Papakostopoulos, V

1999-08-01

Although the science of ergonomics did not actually emerge until the 20th century, there is evidence to suggest that ergonomic principles were in fact known and adhered to 25 centuries ago. The study reported here is a first attempt to research the ergonomics concerns of ancient Greeks, on both a conceptual and a practical level. On the former we present a collection of literature references to the concepts of usability and human-centred design. On the latter, examples of ergonomic design from a variety of fields are analysed. The fields explored here include the design of everyday utensils, the sculpture and manipulation of marble as a building material and the design of theatres. Though hardly exhaustive, these examples serve to demonstrate that the ergonomics principles, in content if not in name, actually emerged a lot earlier than is traditionally thought.

Nanomaterials in the field of design ergonomics: present status.

PubMed

Chowdhury, Anirban; Sanjog, J; Reddy, Swathi Matta; Karmakar, Sougata

2012-01-01

Application of nanotechnology and nanomaterials is not new in the field of design, but a recent trend of extensive use of nanomaterials in product and/or workplace design is drawing attention of design researchers all over the world. In the present paper, an attempt has been made to describe the diverse use of nanomaterials in product and workplace design with special emphasis on ergonomics (occupational health and safety; thermo-regulation and work efficiency, cognitive interface design; maintenance of workplace, etc.) to popularise the new discipline 'nanoergonomics' among designers, design users and design researchers. Nanoergonomics for sustainable product and workplace design by minimising occupational health risks has been felt by the authors to be an emerging research area in coming years. Use of nanomaterials in the field of design ergonomics is less explored till date. In the present review, an attempt has been made to extend general awareness among ergonomists/designers about applications of nanomaterials/nanotechnology in the field of design ergonomics and about health implications of nanomaterials during their use.

Beam dynamics validation of the Halbach Technology FFAG Cell for Cornell-BNL Energy Recovery Linac

NASA Astrophysics Data System (ADS)

Méot, F.; Tsoupas, N.; Brooks, S.; Trbojevic, D.

2018-07-01

The Cornell-BNL Electron Test Accelerator (CBETA), a 150 MeV energy recovery linac (ERL) now in construction at Cornell, employs a fixed-field alternating gradient optics return loop: a single beam line comprised of FFAG cells, which accepts four recirculated energies. CBETA FFAG cell uses Halbach permanent magnet technology, its design studies have covered an extended period of time supported by extensive particle dynamics simulations using computed 3-D field map models. This approach is discussed, and illustrated here, based on the final stage in these beam dynamics studies, namely the validation of a ultimate, optimized design of the Halbach cell.

Studies of $${\\rm Nb}_{3}{\\rm Sn}$$ Strands Based on the Restacked-Rod Process for High Field Accelerator Magnets

DOE PAGES

Barzi, E.; Bossert, M.; Gallo, G.; ...

2011-12-21

A major thrust in Fermilab's accelerator magnet R&D program is the development of Nb 3Sn wires which meet target requirements for high field magnets, such as high critical current density, low effective filament size, and the capability to withstand the cabling process. The performance of a number of strands with 150/169 restack design produced by Oxford Superconducting Technology was studied for round and deformed wires. To optimize the maximum plastic strain, finite element modeling was also used as an aid in the design. Results of mechanical, transport and metallographic analyses are presented for round and deformed wires.

Relation between experimental and non-experimental study designs. HB vaccines: a case study

PubMed Central

Jefferson, T.; Demicheli, V.

1999-01-01

STUDY OBJECTIVE: To examine the relation between experimental and non- experimental study design in vaccinology. DESIGN: Assessment of each study design's capability of testing four aspects of vaccine performance, namely immunogenicity (the capacity to stimulate the immune system), duration of immunity conferred, incidence and seriousness of side effects, and number of infections prevented by vaccination. SETTING: Experimental and non-experimental studies on hepatitis B (HB) vaccines in the Cochrane Vaccines Field Database. RESULTS: Experimental and non-experimental vaccine study designs are frequently complementary but some aspects of vaccine quality can only be assessed by one of the types of study. More work needs to be done on the relation between study quality and its significance in terms of effect size.   PMID:10326054

Design and simulation of the micromixer with chaotic advection in twisted microchannels.

PubMed

Jen, Chun-Ping; Wu, Chung-Yi; Lin, Yu-Cheng; Wu, Ching-Yi

2003-05-01

Chaotic mixers with twisted microchannels were designed and simulated numerically in the present study. The phenomenon whereby a simple Eulerian velocity field may generate a chaotic response in the distribution of a Lagrangian marker is termed chaotic advection. Dynamic system theory indicates that chaotic particle motion can occur when a velocity field is either two-dimensional and time-dependent, or three-dimensional. In the present study, micromixers with three-dimensional structures of the twisted microchannel were designed in order to induce chaotic mixing. In addition to the basic T-mixer, three types of micromixers with inclined, oblique and wavelike microchannels were investigated. In the design of each twisted microchannel, the angle of the channels' bottoms alternates in each subsection. When the fluids enter the twisted microchannels, the flow sways around the varying structures within the microchannels. The designs of the twisted microchannels provide a third degree of freedom to the flow field in the microchannel. Therefore, chaotic regimes that lead to chaotic mixing may arise. The numerical results indicate that mixing occurs in the main channel and progressively larger mixing lengths are required as the Peclet number increased. The swaying of the flow in the twisted microchannel causes chaotic advection. Among the four micromixer designs, the micromixer with the inclined channel most improved mixing. Furthermore, using the inclined mixer with six subsections yielded optimum performance, decreasing the mixing length by up to 31% from that of the basic T-mixer.

Tucson Diversion Channel. Phase I. Sport Fields & Picnic Area. Feature Design Memorandum Number 3.

DTIC Science & Technology

1983-04-01

opportunities for picnicking, a variety of field sports and court games , archery, jogging, and bicycling. d. Rapid urban growth in the Tucson metropolitan area...AD’A136 927 TUCSON DIVERSION CHANNEL PHASE I SPORT FIELDS A PICNI IC J AREA FEATURE DESIGN MEMORANDUM NUMBER 3(U) ARMY ENGINEER DISTRICT LOS ANGELES...TUCSON DIVERSION CHMNEL DESIGN EIORANDUK NO. 3 FEATURE DESIGN MNRORANDIJ PHASE I SPORT FIELDS & PICNIC AREA APRIL 1983 t1 US AM CORPS OF

"From the Formal to the Innovative": The Use of Case Studies and Sustainable Projects in Developing a Design Process Model for Educating Product/Industrial Designers

ERIC Educational Resources Information Center

Oakes, G. L.; Felton, A. J.; Garner, K. B.

2006-01-01

The BSc in computer aided product design (CAPD) course at the University of Wolverhampton was conceived as a collaborative venture in 1989 between the School of Engineering and the School of Art and Design. The award was at the forefront of forging interdisciplinary collaboration at undergraduate level in the field of product design. It has…

Solid-state X-band Combiner Study

NASA Technical Reports Server (NTRS)

Pitzalis, O., Jr.; Russell, K. J.

1979-01-01

The feasibility of developing solid-state amplifiers at 4 and 10 GHz for application in spacecraft altimeters was studied. Bipolar-transistor, field-effect-transistor, and Impatt-diode amplifier designs based on 1980 solid-state technology are investigated. Several output power levels of the pulsed, low-duty-factor amplifiers are considered at each frequency. Proposed transistor and diode amplifier designs are illustrated in block diagrams. Projections of size, weight, and primary power requirements are given for each design.

Magnetic field mapping of the UCNTau magneto-gravitational trap: design study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Libersky, Matthew Murray

2014-09-04

The beta decay lifetime of the free neutron is an important input to the Standard Model of particle physics, but values measured using different methods have exhibited substantial disagreement. The UCN r experiment in development at Los Alamos National Laboratory (LANL) plans to explore better methods of measuring the neutron lifetime using ultracold neutrons (UCNs). In this experiment, UCNs are confined in a magneto-gravitational trap formed by a curved, asymmetric Halbach array placed inside a vacuum vessel and surrounded by holding field coils. If any defects present in the Halbach array are sufficient to reduce the local field near themore » surface below that needed to repel the desired energy level UCNs, loss by material interaction can occur at a rate similar to the loss by beta decay. A map of the magnetic field near the surface of the array is necessary to identify any such defects, but the array's curved geometry and placement in a vacuum vessel make conventional field mapping methods difficult. A system consisting of computer vision-based tracking and a rover holding a Hall probe has been designed to map the field near the surface of the array, and construction of an initial prototype has begun at LANL. The design of the system and initial results will be described here.« less

Simulated Design Strategies for SPECT Collimators to Reduce the Eddy Currents Induced by MRI Gradient Fields

NASA Astrophysics Data System (ADS)

Samoudi, Amine M.; Van Audenhaege, Karen; Vermeeren, Günter; Verhoyen, Gregory; Martens, Luc; Van Holen, Roel; Joseph, Wout

2015-10-01

Combining single photon emission computed tomography (SPECT) with magnetic resonance imaging (MRI) requires the insertion of highly conductive SPECT collimators inside the MRI scanner, resulting in an induced eddy current disturbing the combined system. We reduced the eddy currents due to the insert of a novel tungsten collimator inside transverse and longitudinal gradient coils. The collimator was produced with metal additive manufacturing, that is part of a microSPECT insert for a preclinical SPECT/MRI scanner. We characterized the induced magnetic field due to the gradient field and adapted the collimators to reduce the induced eddy currents. We modeled the x-, y-, and z-gradient coil and the different collimator designs and simulated them with FEKO, a three-dimensional method of moments / finite element methods (MoM/FEM) full-wave simulation tool. We used a time analysis approach to generate the pulsed magnetic field gradient. Simulation results show that the maximum induced field can be reduced by 50.82% in the final design bringing the maximum induced magnetic field to less than 2% of the applied gradient for all the gradient coils. The numerical model was validated with measurements and was proposed as a tool for studying the effect of a SPECT collimator within the MRI gradient coils.

Near- and Far-Field Characterization of Planar mm-Wave Antenna Arrays with Waveguide-to-Microstrip Transition

NASA Astrophysics Data System (ADS)

Salhi, Mohammed Adnan; Kazemipour, Alireza; Gentille, Gennaro; Spirito, Marco; Kleine-Ostmann, Thomas; Schrader, Thorsten

2016-09-01

We present the design and characterization of planar mm-wave patch antenna arrays with waveguide-to-microstrip transition using both near- and far-field methods. The arrays were designed for metrological assessment of error sources in antenna measurement. One antenna was designed for the automotive radar frequency range at 77 GHz, while another was designed for the frequency of 94 GHz, which is used, e.g., for imaging radar applications. In addition to the antennas, a simple transition from rectangular waveguide WR-10 to planar microstrip line on Rogers 3003™ substrate has been designed based on probe coupling. For determination of the far-field radiation pattern of the antennas, we compare results from two different measurement methods to simulations. Both a far-field antenna measurement system and a planar near-field scanner with near-to-far-field transformation were used to determine the antenna diagrams. The fabricated antennas achieve a good matching and a good agreement between measured and simulated antenna diagrams. The results also show that the far-field scanner achieves more accurate measurement results with regard to simulations than the near-field scanner. The far-field antenna scanning system is built for metrological assessment and antenna calibration. The antennas are the first which were designed to be tested with the measurement system.

Selecting a proper design period for heliostat field layout optimization using Campo code

NASA Astrophysics Data System (ADS)

Saghafifar, Mohammad; Gadalla, Mohamed

2016-09-01

In this paper, different approaches are considered to calculate the cosine factor which is utilized in Campo code to expand the heliostat field layout and maximize its annual thermal output. Furthermore, three heliostat fields containing different number of mirrors are taken into consideration. Cosine factor is determined by considering instantaneous and time-average approaches. For instantaneous method, different design days and design hours are selected. For the time average method, daily time average, monthly time average, seasonally time average, and yearly time averaged cosine factor determinations are considered. Results indicate that instantaneous methods are more appropriate for small scale heliostat field optimization. Consequently, it is proposed to consider the design period as the second design variable to ensure the best outcome. For medium and large scale heliostat fields, selecting an appropriate design period is more important. Therefore, it is more reliable to select one of the recommended time average methods to optimize the field layout. Optimum annual weighted efficiency for heliostat fields (small, medium, and large) containing 350, 1460, and 3450 mirrors are 66.14%, 60.87%, and 54.04%, respectively.

An Innovative Approach to the Design and Implementation of an International Finance Field Study Course

ERIC Educational Resources Information Center

Wynne, Kevin; Filante, Ronald W.

2004-01-01

Internationalization of a business school curriculum has long been an important objective of AACSB-accredited schools in the United States. During the past 4 years, the authors of this article have developed, taught, and guided an undergraduate finance field study course that has incorporated trips to London, Dublin, and Paris. In this article,…

Forum Theatre and Parables: A Qualitative Field Experiment in a Seventh-Day Adventist Academy

ERIC Educational Resources Information Center

Freed, Dena Davis

2012-01-01

In this article, the author describes a qualitative field study designed to test the effectiveness of Forum Theatre (FT) as a cross-disciplinary approach to Biblical parabolic literature analysis for students enrolled in a Seventh-day Adventist (SDA) Academy. The author provides a brief overview of the theoretical framework of the study, the study…

NADE Members Respond--Developmental Education Research Agenda: Survey of Field Professionals, Part 2

ERIC Educational Resources Information Center

Saxon, D. Patrick; Martirosyan, Nara M.; Wentworth, Rebecca A.; Boylan, Hunter R.

2015-01-01

This is the final of a two-part article that provides the results of a qualitative study designed to document ideas and beliefs that professionals have regarding an appropriate research agenda on which the field of developmental education should focus in the near future. The participants of the study were members of the National Association for…

Initial design of 12S-10P outer-rotor field excitation flux switching motor with different rotor width

NASA Astrophysics Data System (ADS)

Othman, Syed Muhammad Naufal bin Syed; Sulaiman, Erwan bin; Husin, Zhafir Aizat; Khan, Faisal; Mazlan, Mohamed Mubin Aizat

2015-05-01

This paper proposes an initial design of 12 slot, 10 pole outer-rotor field-excitation flux switching motor (FEFSM) with two different rotor width based from 2 different formula to design the rotor width. Hence, initial design include the three coil test to determine the U, W, V-phase, the flux strengthening and weakening, flux at various armature coil and field-excitation coil current, and finally the torque at various JA and JE. As for the materials, the stator and rotor consists of steel sheets made of electromagnetic steels, copper for armature coils and field excitation coils as the only field for magnetic flux source. There will be some design specification and restriction on outer-rotor FEFSM based on 2D-Finite Element Analysis will be applied to design the proposed machine.

Design and Fabrication of Helmholtz Coils to Study the Effects of Pulsed Electromagnetic Fields on the Healing Process in Periodontitis: Preliminary Animal Results

PubMed Central

Haghnegahdar, A; Khosrovpanah, H; Andisheh-Tadbir, A; Mortazavi, Gh; Saeedi Moghadam, M; Mortazavi, SMJ; Zamani, A; Haghani, M; Shojaei Fard, M; Parsaei, H; Koohi, O

2014-01-01

Background: Effects of electromagnetic fields on healing have been investigated for centuries. Substantial data indicate that exposure to electromagnetic field can lead to enhanced healing in both soft and hard tissues. Helmholtz coils are devices that generate pulsed electromagnetic fields (PEMF). Objective: In this work, a pair of Helmholtz coils for enhancing the healing process in periodontitis was designed and fabricated. Method: An identical pair of square Helmholtz coils generated the 50 Hz magnetic field.  This device was made up of two parallel coaxial circular coils (100 turns in each loop, wound in series) which were separated from each other by a distance equal to the radius of one coil (12.5 cm). The windings of our Helmholtz coil was made of standard 0.95mm wire to provide the maximum possible current. The coil was powered by a function generator.  Results: The Helmholtz Coils generated a uniform magnetic field between its coils. The magnetic field strength at the center of the space between two coils was 97.6 μT. Preliminary biological studies performed on rats show that exposure of laboratory animals to pulsed electromagnetic fields enhanced the healing of periodontitis. Conclusion: Exposure to PEMFs can lead to stimulatory physiological effects on cells and tissues such as enhanced healing of periodontitis. PMID:25505775

Design of sparse Halbach magnet arrays for portable MRI using a genetic algorithm.

PubMed

Cooley, Clarissa Zimmerman; Haskell, Melissa W; Cauley, Stephen F; Sappo, Charlotte; Lapierre, Cristen D; Ha, Christopher G; Stockmann, Jason P; Wald, Lawrence L

2018-01-01

Permanent magnet arrays offer several attributes attractive for the development of a low-cost portable MRI scanner for brain imaging. They offer the potential for a relatively lightweight, low to mid-field system with no cryogenics, a small fringe field, and no electrical power requirements or heat dissipation needs. The cylindrical Halbach array, however, requires external shimming or mechanical adjustments to produce B 0 fields with standard MRI homogeneity levels (e.g., 0.1 ppm over FOV), particularly when constrained or truncated geometries are needed, such as a head-only magnet where the magnet length is constrained by the shoulders. For portable scanners using rotation of the magnet for spatial encoding with generalized projections, the spatial pattern of the field is important since it acts as the encoding field. In either a static or rotating magnet, it will be important to be able to optimize the field pattern of cylindrical Halbach arrays in a way that retains construction simplicity. To achieve this, we present a method for designing an optimized cylindrical Halbach magnet using the genetic algorithm to achieve either homogeneity (for standard MRI applications) or a favorable spatial encoding field pattern (for rotational spatial encoding applications). We compare the chosen designs against a standard, fully populated sparse Halbach design, and evaluate optimized spatial encoding fields using point-spread-function and image simulations. We validate the calculations by comparing to the measured field of a constructed magnet. The experimentally implemented design produced fields in good agreement with the predicted fields, and the genetic algorithm was successful in improving the chosen metrics. For the uniform target field, an order of magnitude homogeneity improvement was achieved compared to the un-optimized, fully populated design. For the rotational encoding design the resolution uniformity is improved by 95% compared to a uniformly populated design.

A novel beam optics concept in a particle therapy gantry utilizing the advantages of superconducting magnets.

PubMed

Gerbershagen, Alexander; Meer, David; Schippers, Jacobus Maarten; Seidel, Mike

2016-09-01

A first order design of the beam optics of a superconducting proton therapy gantry beam is presented. The possibilities of superconducting magnets with respect to the beam optics such as strong fields, large apertures and superposition of different multipole fields have been exploited for novel concepts in a gantry. Since various techniques used in existing gantries have been used in our first design steps, some examples of the existing superconducting gantry designs are described and the necessary requirements of such a gantry are explained. The study of a gantry beam optics design is based on superconducting combined function magnets. The simulations have been performed in first order with the conventional beam transport codes. The superposition of strong dipole and quadrupole fields generated by superconducting magnets enables the introduction of locally achromatic bending sections without increasing the gantry size. A rigorous implementation of such beam optics concepts into the proposed gantry design dramatically increases the momentum acceptance compared to gantries with normal conducting magnets. In our design this large acceptance has been exploited by the implementation of a degrader within the gantry and a potential possibility to use the same magnetic field for all energies used in a treatment, so that the superconducting magnets do not have to vary their fields during a treatment. This also enables very fast beam energy changes, which is beneficial for spreading the Bragg peak over the thickness of the tumor. The results show an improvement of its momentum acceptance. Large momentum acceptance in the gantry creates a possibility to implement faster dose application techniques. Copyright © 2016. Published by Elsevier GmbH.

Optimization design and laser damage threshold analysis of pulse compression multilayer dielectric gratings

NASA Astrophysics Data System (ADS)

Fan, Shuwei; Bai, Liang; Chen, Nana

2016-08-01

As one of the key elements of high-power laser systems, the pulse compression multilayer dielectric grating is required for broader band, higher diffraction efficiency and higher damage threshold. In this paper, the multilayer dielectric film and the multilayer dielectric gratings(MDG) were designed by eigen matrix and optimized with the help of generic algorithm and rigorous coupled wave method. The reflectivity was close to 100% and the bandwith were over 250nm, twice compared to the unoptimized film structure. The simulation software of standing wave field distribution within MDG was developed and the electric field of the MDG was calculated. And the key parameters which affected the electric field distribution were also studied.

Advanced Field Artillery System (AFAS) Future Armored Resupply Vehicle (FARV) Simulation Feasibility Analysis Study (FAS). Appendix C-F. Revision 1.0

DTIC Science & Technology

1994-07-18

09 Software Product Training 3 .4 .11 Physical Cues Segment Development3 .01 Technical Management .02 SW Requirements Analysis .03 Preliminary Design...Mission Planning Subsystem Development3 .01 Technical Management .02 SW Requirements Analysis .03 Preliminary Design - .04 Detailed Design .05 Code & CSU

A Field Study of Performance Among Embarked Infantry Personnel Exposed to Waterborne Motion

DTIC Science & Technology

2012-09-01

was designed with four groups with 16 participants per group to accommodate the calculated sample size and the maximum seating capacity of the...25  A.  APPROACH TO THE EXPERIMENTAL DESIGN .................................25  B.  VARIABLES...39  viii 1.  Design of the Training Period ...........................................................39  2.  Training Period

The Effectiveness of Scaffolding Design in Training Writing Skills Physics Teaching Materials

ERIC Educational Resources Information Center

Sinaga, Parlindungan; Suhandi, Andi; Liliasari

2015-01-01

Result of field studies showed low writing skill of teachers in teaching material. The root of the problem lies in their inability on translating description of teaching material into writing. This research focused on the effectiveness of scaffolding design. The scaffolding design was tested in the selected topics of physics courses for…

Design and Use of Interactive Social Stories for Children with Autism Spectrum Disorder (ASD)

ERIC Educational Resources Information Center

Sani-Bozkurt, Sunagul; Vuran, Sezgin; Akbulut, Yavuz

2017-01-01

The current study aimed to design technology-supported interactive social stories to teach social skills to children with autism spectrum disorder (ASD). A design-based research was implemented with children with ASD along with the participation of their mothers, teachers, peers and field experts. An iterative remediation process was followed…

National Study of Social Welfare and Rehabilitation Workers, Work, and Organizational Contexts. Research Report No. 1: Overview Study of the Dynamics of Worker Job Mobility.

ERIC Educational Resources Information Center

Social and Rehabilitation Service (DHEW), Washington, DC.

The goals of this study were to review what is known about worker job mobility in the social welfare and rehabilitation services fields, to organize this knowledge, and to suggest improvements in career design and employee management in these fields. To supplement the review of research and theoretical literature, two sets of personal interviews…

Field size, length, and width distributions based on LACIE ground truth data. [large area crop inventory experiment

NASA Technical Reports Server (NTRS)

Pitts, D. E.; Badhwar, G.

1980-01-01

The development of agricultural remote sensing systems requires knowledge of agricultural field size distributions so that the sensors, sampling frames, image interpretation schemes, registration systems, and classification systems can be properly designed. Malila et al. (1976) studied the field size distribution for wheat and all other crops in two Kansas LACIE (Large Area Crop Inventory Experiment) intensive test sites using ground observations of the crops and measurements of their field areas based on current year rectified aerial photomaps. The field area and size distributions reported in the present investigation are derived from a representative subset of a stratified random sample of LACIE sample segments. In contrast to previous work, the obtained results indicate that most field-size distributions are not log-normally distributed. The most common field size observed in this study was 10 acres for most crops studied.

Study of the flow mixing in a novel ARID raceway for algae production

DOE PAGES

Xu, Ben; Li, Peiwen; Waller, P.

2014-07-31

A novel flow field for algae raceways has been proposed, which is fundamentally different from traditional paddlewheel-driven raceways. To reduce freezing and heat loss in the raceway during cold time, the water is drained to a deep storage canal. The ground bed of the new raceway has a low slope so that water, lifted by propeller pump, can flow down in laterally-laid serpentine channels, relying on gravitational force. The flow rate of water is controlled so that it can overflow the lateral channel walls and mix with the main flow in the next lower channel, which thus creates a bettermore » mixing. In order to optimize the design parameters of the new flow field, methods including flow visualization, local point velocity measurement, and CFD analysis were employed to investigate the flow mixing features. Different combinations of channel geometries and water velocities were evaluated. An optimized flow field design and details of flow mixing are presented. The study offers an innovative design for large scale algae growth raceways which is of significance to the algae and biofuel industry.« less

Study of the flow mixing in a novel ARID raceway for algae production

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xu, Ben; Li, Peiwen; Waller, P.

A novel flow field for algae raceways has been proposed, which is fundamentally different from traditional paddlewheel-driven raceways. To reduce freezing and heat loss in the raceway during cold time, the water is drained to a deep storage canal. The ground bed of the new raceway has a low slope so that water, lifted by propeller pump, can flow down in laterally-laid serpentine channels, relying on gravitational force. The flow rate of water is controlled so that it can overflow the lateral channel walls and mix with the main flow in the next lower channel, which thus creates a bettermore » mixing. In order to optimize the design parameters of the new flow field, methods including flow visualization, local point velocity measurement, and CFD analysis were employed to investigate the flow mixing features. Different combinations of channel geometries and water velocities were evaluated. An optimized flow field design and details of flow mixing are presented. The study offers an innovative design for large scale algae growth raceways which is of significance to the algae and biofuel industry.« less

eLISA Telescope In-field Pointing and Scattered Light Study

NASA Astrophysics Data System (ADS)

Livas, J.; Sankar, S.; West, G.; Seals, L.; Howard, J.; Fitzsimons, E.

2017-05-01

The orbital motion of the three spacecraft that make up the eLISA Observatory constellation causes long-arm line of sight variations of approximately ± one degree over the course of a year. The baseline solution is to package the telescope, the optical bench, and the gravitational reference sensor (GRS) into an optical assembly at each end of the measurement arm, and then to articulate the assembly. An optical phase reference is exchanged between the moving optical benches with a single mode optical fiber (“backlink” fiber). An alternative solution, referred to as in-field pointing, embeds a steering mirror into the optical design, fixing the optical benches and eliminating the backlink fiber, but requiring the additional complication of a two-stage optical design for the telescope. We examine the impact of an in-field pointing design on the scattered light performance.

Cryogenic solid Schmidt camera as a base for future wide-field IR systems

NASA Astrophysics Data System (ADS)

Yudin, Alexey N.

2011-11-01

Work is focused on study of capability of solid Schmidt camera to serve as a wide-field infrared lens for aircraft system with whole sphere coverage, working in 8-14 um spectral range, coupled with spherical focal array of megapixel class. Designs of 16 mm f/0.2 lens with 60 and 90 degrees sensor diagonal are presented, their image quality is compared with conventional solid design. Achromatic design with significantly improved performance, containing enclosed soft correcting lens behind protective front lens is proposed. One of the main goals of the work is to estimate benefits from curved detector arrays in 8-14 um spectral range wide-field systems. Coupling of photodetector with solid Schmidt camera by means of frustrated total internal reflection is considered, with corresponding tolerance analysis. The whole lens, except front element, is considered to be cryogenic, with solid Schmidt unit to be flown by hydrogen for improvement of bulk transmission.

DIRECT operational field test evaluation : natural use study : part 2 : driver satisfaction in DIRECT controlling for reliability

DOT National Transportation Integrated Search

1998-08-01

This report describes the DIRECT field test which was designed to evaluate the user benefits, institutional issues, and technical issues of en-route driver advisory and traveler information services. Focus was on testing and evaluating the voice-base...

Evaluation of fatigue-prone details using a low-cost thermoelastic stress analysis system.

DOT National Transportation Integrated Search

2016-11-01

This study was designed to develop a novel approach for in situ evaluation of stress fields in the vicinity of fatigue-prone details on highway bridges using a low-cost microbolometer thermal imager. : The method was adapted into a field-deployable i...

Multitrophic Cry-protein flow in Bt-cotton

USDA-ARS?s Scientific Manuscript database

Although most genetically engineered cotton plants grown today produce the insecticidal Cry-proteins Cry1Ac and Cry2Ab, studies are lacking on multitrophic Cry-protein acquisition in dual-gene cotton fields. Such field data are important for the design and interpretation of laboratory risk assessmen...

The application of mixed methods designs to trauma research.

PubMed

Creswell, John W; Zhang, Wanqing

2009-12-01

Despite the use of quantitative and qualitative data in trauma research and therapy, mixed methods studies in this field have not been analyzed to help researchers designing investigations. This discussion begins by reviewing four core characteristics of mixed methods research in the social and human sciences. Combining these characteristics, the authors focus on four select mixed methods designs that are applicable in trauma research. These designs are defined and their essential elements noted. Applying these designs to trauma research, a search was conducted to locate mixed methods trauma studies. From this search, one sample study was selected, and its characteristics of mixed methods procedures noted. Finally, drawing on other mixed methods designs available, several follow-up mixed methods studies were described for this sample study, enabling trauma researchers to view design options for applying mixed methods research in trauma investigations.

South American Field Experience: An Initiative in International Education. The Implementation Journal for the South American Field Experience.

ERIC Educational Resources Information Center

Martin, William J.

A description is provided of Williamsport Area Community College's (WACC's) South American Field Experience program, a travel/study program for faculty and staff designed to provide a variety of learning experiences through a three week trip to Peru, Chile, Argentina, and Brazil. Chapter I presents an overview of the development of the project,…

DOE Office of Scientific and Technical Information (OSTI.GOV)

Imani, Mohammadreza F., E-mail: mohamad.imani@gmail.com; Grbic, Anthony

One of the obstacles preventing wireless power transfer from becoming ubiquitous is their leakage of power: high-amplitude electromagnetic fields that can interfere with other electronic devices, increase health concerns, or hinder power metering. In this paper, we present near-field plates (NFPs) as a novel method to tailor the electromagnetic fields generated by a wireless power transfer system while maintaining high efficiency. NFPs are modulated arrays or surfaces designed to form prescribed near-field patterns. The NFP proposed in this paper consists of an array of loaded loops that are designed to confine the electromagnetic fields of a resonant transmitting loop tomore » the desired direction (receiving loop) while suppressing fields in other directions. The step-by-step design procedure for this device is outlined. Two NFPs are designed and examined in full-wave simulation. Their performance is shown to be in close agreement with the design predictions, thereby verifying the proposed design and operation. A NFP is also fabricated and experimentally shown to form a unidirectional wireless power transfer link with high efficiency.« less

Field guide for collecting and processing stream-water samples for the National Water-Quality Assessment Program

USGS Publications Warehouse

Shelton, Larry R.

1994-01-01

The U.S. Geological Survey's National Water-Quality Assessment program includes extensive data- collection efforts to assess the quality of the Nations's streams. These studies require analyses of stream samples for major ions, nutrients, sediments, and organic contaminants. For the information to be comparable among studies in different parts of the Nation, consistent procedures specifically designed to produce uncontaminated samples for trace analysis in the laboratory are critical. This field guide describes the standard procedures for collecting and processing samples for major ions, nutrients, organic contaminants, sediment, and field analyses of conductivity, pH, alkalinity, and dissolved oxygen. Samples are collected and processed using modified and newly designed equipment made of Teflon to avoid contamination, including nonmetallic samplers (D-77 and DH-81) and a Teflon sample splitter. Field solid-phase extraction procedures developed to process samples for organic constituent analyses produce an extracted sample with stabilized compounds for more accurate results. Improvements to standard operational procedures include the use of processing chambers and capsule filtering systems. A modified collecting and processing procedure for organic carbon is designed to avoid contamination from equipment cleaned with methanol. Quality assurance is maintained by strict collecting and processing procedures, replicate sampling, equipment blank samples, and a rigid cleaning procedure using detergent, hydrochloric acid, and methanol.

Freeform Optical Design of Two Mirror Telescopes

NASA Technical Reports Server (NTRS)

Howard, Joseph; West, Garrett; Trumper, Isaac; Anderson, Alex

2015-01-01

Two Mirror telescopes composed of freeform optical surfaces are investigated and surveyed to explore the usable design space. F-number and field of view are evaluated and plotted. A case study is presented to show the benefits of volume reduction using freeform surfaces.

Field evaluation of alternative and cost efficient bridge approach slabs.

DOT National Transportation Integrated Search

2013-11-01

Based on a recent study on cost efficient alternative bridge approach slab (BAS) designs (Thiagarajan et al. 2010) has recommended : three new BAS designs for possible implementation by MoDOT namely a) 20 feet cast-inplace slab with sleeper slab (CIP...

Experimental Design for Evaluating the Safety Benefits of Railroad Advance Warning Signs

DOT National Transportation Integrated Search

1979-04-01

The report presents the findings and conclusions of a study to develop an experimental design and analysis plan for field testing and evaluation of the accident reduction potential of a proposed new railroad grade crossing advance warning sign. Sever...

Improving the conspicuity of trailblazing signs for incident management.

DOT National Transportation Integrated Search

1998-03-01

This report represents efforts to design and evaluate a new sign design for emergency route trailblazing in a two-part series. : Study was an off-road field experiment conducted to determine the best sign color combination, letter stroke width, and l...

Numerical simulations on active shielding methods comparison and wrapped angle optimization for gradient coil design in MRI with enhanced shielding effect

NASA Astrophysics Data System (ADS)

Wang, Yaohui; Xin, Xuegang; Guo, Lei; Chen, Zhifeng; Liu, Feng

2018-05-01

The switching of a gradient coil current in magnetic resonance imaging will induce an eddy current in the surrounding conducting structures while the secondary magnetic field produced by the eddy current is harmful for the imaging. To minimize the eddy current effects, the stray field shielding in the gradient coil design is usually realized by minimizing the magnetic fields on the cryostat surface or the secondary magnetic fields over the imaging region. In this work, we explicitly compared these two active shielding design methods. Both the stray field and eddy current on the cryostat inner surface were quantitatively discussed by setting the stray field constraint with an ultra-low maximum intensity of 2 G and setting the secondary field constraint with an extreme small shielding ratio of 0.000 001. The investigation revealed that the secondary magnetic field control strategy can produce coils with a better performance. However, the former (minimizing the magnetic fields) is preferable when designing a gradient coil with an ultra-low eddy current that can also strictly control the stray field leakage at the edge of the cryostat inner surface. A wrapped-edge gradient coil design scheme was then optimized for a more effective control of the stray fields. The numerical simulation on the wrapped-edge coil design shows that the optimized wrapping angles for the x and z coils in terms of our coil dimensions are 40° and 90°, respectively.

Joint design of large-tip-angle parallel RF pulses and blipped gradient trajectories.

PubMed

Cao, Zhipeng; Donahue, Manus J; Ma, Jun; Grissom, William A

2016-03-01

To design multichannel large-tip-angle kT-points and spokes radiofrequency (RF) pulses and gradient waveforms for transmit field inhomogeneity compensation in high field magnetic resonance imaging. An algorithm to design RF subpulse weights and gradient blip areas is proposed to minimize a magnitude least-squares cost function that measures the difference between realized and desired state parameters in the spin domain, and penalizes integrated RF power. The minimization problem is solved iteratively with interleaved target phase updates, RF subpulse weights updates using the conjugate gradient method with optimal control-based derivatives, and gradient blip area updates using the conjugate gradient method. Two-channel parallel transmit simulations and experiments were conducted in phantoms and human subjects at 7 T to demonstrate the method and compare it to small-tip-angle-designed pulses and circularly polarized excitations. The proposed algorithm designed more homogeneous and accurate 180° inversion and refocusing pulses than other methods. It also designed large-tip-angle pulses on multiple frequency bands with independent and joint phase relaxation. Pulses designed by the method improved specificity and contrast-to-noise ratio in a finger-tapping spin echo blood oxygen level dependent functional magnetic resonance imaging study, compared with circularly polarized mode refocusing. A joint RF and gradient waveform design algorithm was proposed and validated to improve large-tip-angle inversion and refocusing at ultrahigh field. © 2015 Wiley Periodicals, Inc.

Recreation safety in municipal parks - Bloomington, Indiana and Tsukuba, Japan: a comparison study of risk management

Treesearch

Bruce Hronek

2001-01-01

Cultural differences affects the design and use of playground equipment in parks. Comparative research exploring the differences in playground facilities, parental supervision, and use was conducted on-site in Tsukuba City, Ibaraki Perfecture, Japan and Bloomington, Indiana, USA. The study examines park design, play equipment, sports fields, use patterns, and parental...

DOE Office of Scientific and Technical Information (OSTI.GOV)

Logan, B.G.

A recently completed two-year study of a commercial tandem mirror reactor design (Mirror Advanced Reactor Study (MARS)) is briefly reviewed. The end plugs are designed for trapped particle stability, MHD ballooning, balanced geodesic curvature, and small radial electric fields in the central cell. New technologies such as lithium-lead blankets, 24T hybrid coils, gridless direct converters and plasma halo vacuum pumps are highlighted.

Development of a study design and implementation plan to estimate juvenile salmon survival in Lookout Point Reservoir and other reservoirs of the Willamette Project, western Oregon

USGS Publications Warehouse

Kock, Tobias J.; Perry, Russell W.; Monzyk, Fred R.; Pope, Adam C.; Plumb, John M.

2016-12-23

Survival estimates for juvenile salmon and steelhead fry in reservoirs impounded by high head dams are coveted data by resource managers.  However, this information is difficult to obtain because these fish are too small for tagging using conventional methods such as passive-integrated transponders or radio or acoustic transmitters.  We developed a study design and implementation plan to conduct a pilot evaluation that would assess the performance of two models for estimating fry survival in a field setting.  The first model is a staggered-release recovery model that was described by Skalski and others (2009) and Skalski (2016).  The second model is a parentage-based tagging N-mixture model that was developed and described in this document.  Both models are conceptually and statistically sound, but neither has been evaluated in the field.  In this document we provide an overview of a proposed study for 2017 in Lookout Point Reservoir, Oregon, that will evaluate survival of Chinook salmon fry using both models.  This approach will allow us to test each model and compare survival estimates, to determine model performance and better understand these study designs using field-collected data.

A case study on better iconographic design in electronic medical records' user interface.

PubMed

Tasa, Umut Burcu; Ozcan, Oguzhan; Yantac, Asim Evren; Unluer, Ayca

2008-06-01

It is a known fact that there is a conflict between what users expect and what user interface designers create in the field of medical informatics along with other fields of interface design. The objective of the study is to suggest, from the 'design art' perspective, a method for improving the usability of an electronic medical record (EMR) interface. The suggestion is based on the hypothesis that the user interface of an EMR should be iconographic. The proposed three-step method consists of a questionnaire survey on how hospital users perceive concepts/terms that are going to be used in the EMR user interface. Then icons associated with the terms are designed by a designer, following a guideline which is prepared according to the results of the first questionnaire. Finally the icons are asked back to the target group for proof. A case study was conducted with 64 medical staff and 30 professional designers for the first questionnaire, and with 30 medical staff for the second. In the second questionnaire 7.53 icons out of 10 were matched correctly with a standard deviation of 0.98. Also, all icons except three were matched correctly in at least 83.3% of the forms. The proposed new method differs from the majority of previous studies which are based on user requirements by leaning on user experiments instead. The study demonstrated that the user interface of EMRs should be designed according to a guideline that results from a survey on users' experiences on metaphoric perception of the terms.

Approaches, field considerations and problems associated with radio tracking carnivores

USGS Publications Warehouse

Sargeant, A.B.; Amlaner, C. J.; MacDonald, D.W.

1979-01-01

The adaptation of radio tracking to ecological studies was a major technological advance affecting field investigations of animal movements and behavior. Carnivores have been the recipients of much attention with this new technology and study approaches have varied from simple to complex. Equipment performance has much improved over the years, but users still face many difficulties. The beginning of all radio tracking studies should be a precise definition of objectives. Study objectives dictate type of gear required and field procedures. Field conditions affect equipment performance and investigator ability to gather data. Radio tracking carnivores is demanding and generally requires greater time than anticipated. Problems should be expected and planned for in study design. Radio tracking can be an asset in carnivore studies but caution is needed in its application.

A proposal of image slicer designed for integral field spectroscopy with NIRSpec/JSWT

NASA Astrophysics Data System (ADS)

Prieto, E.; Vivès, S.

2006-06-01

Integral field spectroscopy (IFS) provides a spectrum simultaneously for each spatial sample of an extended, two-dimensional field. It consists of an integral field unit (IFU) which slices and re-arranges the initial field along the entrance slit of a spectrograph. This article presents a deviation of the classical design of IFU based on the advanced image slicer concept [Content, R., 1997. A new design for integral field spectroscopy with 8-m telescopes. Proc. SPIE 2871, 1295]. To reduce optical aberrations, pupil and slit mirrors are disposed in a fan-shaped configuration that means that angles between incident and reflected beams on each elements are minimized. The fan-shaped image slicer is explained more in details in [Vivès, S., Prieto, E. submitted for publication. An original image slicer designed for Integral Field Spectroscopy with NIRSpec/JSWT. Opt Eng. Available from: ArXiv Physics e-prints, arXiv:0512002.] As an example, we are presenting the design LAM used for its proposal at the NIRSPEC/IFU invitation of tender.

Optical Design Trade Study for the Wide Field Infrared Survey Telescope [WFIRST

NASA Technical Reports Server (NTRS)

Content, David A.; Goullioud, R.; Lehan, John P.; Mentzell, John E.

2011-01-01

The Wide Field Infrared Survey Telescope (WFIRST) mission concept was ranked first in new space astrophysics mission by the Astro2010 Decadal Survey incorporating the Joint Dark Energy Mission (JDEM)-Omega payload concept and multiple science white papers. This mission is based on a space telescope at L2 studying exoplanets [via gravitational microlensing], probing dark energy, and surveying the near infrared sky. Since the release of NWNH, the WFIRST project has been working with the WFIRST science definition team (SDT) to refine mission and payload concepts. We present the driving requirements. The current interim reference mission point design, based on the use of a 1.3m unobscured aperture three mirror anastigmat form, with focal imaging and slitless spectroscopy science channels, is consistent with the requirements, requires no technology development, and out performs the JDEM-Omega design.

Analysis of flow field characteristics in IC equipment chamber based on orthogonal design

NASA Astrophysics Data System (ADS)

Liu, W. F.; Yang, Y. Y.; Wang, C. N.

2017-01-01

This paper aims to study the influence of the configuration of processing chamber as a part of IC equipment on flow field characteristics. Four parameters, including chamber height, chamber diameter, inlet mass flow rate and outlet area, are arranged using orthogonally design method to study their influence on flow distribution in the processing chamber with the commercial software-Fluent. The velocity, pressure and temperature distribution above the holder were analysed respectively. The velocity difference value of the gas flow above the holder is defined as the evaluation criteria to evaluate the uniformity of the gas flow. The quantitative relationship between key parameters and the uniformity of gas flow was found through analysis of experimental results. According to our study, the chamber height is the most significant factor, and then follows the outlet area, chamber diameter and inlet mass flow rate. This research can provide insights into the study and design of configuration of etcher, plasma enhanced chemical vapor deposition (PECVD) equipment, and other systems with similar configuration and processing condition.

Temporary practice pause then resumption (TPPR) study design: an extension of the withdrawal study design to complementary and alternative medicine mind and body interventions (CAM-MABI).

PubMed

Braun, M Miles

2013-10-01

Study of complementary and alternative medicine's mind and body interventions (CAM-MABI) is hindered not only by the inability to mask participants and their teachers to the study intervention but also by the major practical hurdles of long-term study of practices that can be lifelong. Two other important methodological problems are that study of newly trained practitioners cannot directly address long-term practice, and that long-term practitioners likely self-select in ways that make finding appropriate controls (or a comparison group) challenging. The temporary practice pause then resumption study design (TPPR) introduced here is a new tool that extends the withdrawal study design, established in the field of drug evaluation, to the field of CAM-MABI. With the exception of the inability to mask, TPPR can address the other methodological problems noted above. Of great interest to investigators will likely be measures in practitioners of CAM-MABI that change with temporary pausing of CAM-MABI practice, followed by return of the measures to pre-pause levels with resumption of practice; this would suggest a link of the practice to measured changes. Such findings using this tool may enhance our insight into fundamental biological processes, leading to beneficial practical applications.

Observations of the Earth's magnetic field from the Space Station: Measurement at high and extremely low altitude using Space Station-controlled free-flyers

NASA Technical Reports Server (NTRS)

Webster, W., Jr.; Frawley, J. J.; Stefanik, M.

1984-01-01

Simulation studies established that the main (core), crustal and electrojet components of the Earth's magnetic field can be observed with greater resolution or over a longer time-base than is presently possible by using the capabilities provided by the space station. Two systems are studied. The first, a large lifetime, magnetic monitor would observe the main field and its time variation. The second, a remotely-piloted, magnetic probe would observe the crustal field at low altitude and the electrojet field in situ. The system design and the scientific performance of these systems is assessed. The advantages of the space station are reviewed.

Design of the STAR-X Telescope

NASA Technical Reports Server (NTRS)

Saha, Timo T.; Zhang, William W.; McClelland, Ryan S.

2017-01-01

Top-level science goals of the Survey and Time-domain Astrophysical Research eXplorer (STAR-X) include: investigations of most violent explosions in the universe, study of growth of black holes across cosmic time and mass scale, and measure how structure formation heats majority of baryons in the universe. To meet these goals, the field-of-view of the telescope should be about 1 square-degree, the angular resolution should be 5 arc-seconds or below across large part of the field-of-view. The on-axis effective area at 1 KeV should be about 2,000 sq cm. Payload cost and launch considerations limit the outer diameter, focal length, and mass to 1.3 meters, 5 meters, and 250 kilograms, respectively. Telescope design is based on a segmented meta-shell approach we have developed at Goddard Space Flight Center for the STAR-X telescope. The telescope shells are divided into 30-degree segments. Individual telescopes and meta-shells are nested inside each other to meet the effective area requirements in 0.5 - 6.0 KeV range. We consider Wolter-Schwarzschild, and Modified-Wolter-Schwarzschild telescope designs as basic building blocks of the nested STAR-X telescope. These designs offer an excellent resolution over a large field of views. Nested telescopes are vulnerable to stray light problems. We have designed a multi-component baffle system to eliminate direct and single-reflection light paths inside the telescopes. Large number of internal and external baffle vane structures are required to prevent stray rays from reaching the focal plane. We have developed a simple ray-trace based tool to determine the dimensions and locations of the baffles. In this paper, we present the results of our trade studies, baffle design studies, and optical performance analyses of the STAR-X telescope.

Optical Design of the STAR-X Telescope

NASA Technical Reports Server (NTRS)

Saha, Timo T.; Zhang, William W.; McClelland, Ryan S.

2017-01-01

Top-level science goals of the Survey and Time-domain Astrophysical Research eXplorer (STAR-X) include: investigations of most violent explosions in the universe, study of growth of black holes across cosmic time and mass scale, and measure how structure formation heats majority of baryons in the universe. To meet these goals, the field-of-view of the telescope should be about 1 square-degree, the angular resolution should be 5 arc-seconds or below across large part of the field-of-view. The on-axis effective area at 1 KeV should be about 2,000 sq cm. Payload cost and launch considerations limit the outer diameter, focal length, and mass to 1.3 meters, 5 meters, and 250 kilograms, respectively. Telescope design is based on a segmented meta-shell approach we have developed at Goddard Space Flight Center for the STAR-X telescope. The telescope shells are divided into 30-degree segments. Individual telescopes and meta-shells are nested inside each other to meet the effective area requirements in 0.5 - 6.0 KeV range. We consider Wolter-Schwarzschild, and Modified-Wolter-Schwarzschild telescope designs as basic building blocks of the nested STAR-X telescope. These designs offer an excellent resolution over a large field of views. Nested telescopes are vulnerable to stray light problems. We have designed a multi-component baffle system to eliminate direct and single-reflection light paths inside the telescopes. Large number of internal and external baffle vane structures are required to prevent stray rays from reaching the focal plane. We have developed a simple ray-trace based tool to determine the dimensions and locations of the baffles. In this paper, we present the results of our trade studies, baffle design studies, and optical performance analyses of the STAR-X telescope.

Energy Efficiency and Universal Design in Home Renovations - A Comparative Review.

PubMed

Kapedani, Ermal; Herssens, Jasmien; Verbeeck, Griet

2016-01-01

Policy and societal objectives indicate a large need for housing renovations that both accommodate lifelong living and significantly increase energy efficiency. However, these two areas of research are not yet examined in conjunction and this paper hypothesizes this as a missed opportunity to create better renovation concepts. The paper outlines a comparative review on research in Energy Efficiency and Universal Design in order to find the similarities and differences in both depth and breadth of knowledge. Scientific literature in the two fields reveals a disparate depth of knowledge in areas of theory, research approach, and degree of implementation in society. Universal Design and Energy Efficiency are part of a trajectory of expanding scope towards greater sustainability and, although social urgency has been a driver of the research intensity and approach in both fields, in energy efficiency there is an engineering, problem solving approach while Universal Design has a more sociological, user-focused one. These different approaches are reflected in the way home owners in Energy Efficiency research are viewed as consumers and decision makers whose drivers are studied, while Universal Design treats home owners as informants in the design process and studies their needs. There is an inherent difficulty in directly merging Universal Design and Energy Efficiency at a conceptual level because Energy Efficiency is understood as a set of measures, i.e. a product, while Universal Design is part of a (design) process. The conceptual difference is apparent in their implementation as well. Internationally energy efficiency in housing has been largely imposed through legislation, while legislation directly mandating Universal Design is either non-existent or it has an explicit focus on accessibility. However, Energy Efficiency and Universal Design can be complementary concepts and, even though it is more complex than expected, the combination offers possibilities to advance knowledge in both fields.

Methodological Review of Studies on Educational Leaders and Emotions (1992-2012): Insights into the Meaning of an Emerging Research Field in Educational Administration

ERIC Educational Resources Information Center

Berkovich, Izhak; Eyal, Ori

2017-01-01

Purpose: The purpose of this paper is to do methodological review of the literature on educational leaders and emotions that includes 49 empirical studies published in peer-reviewed journals between 1992 and 2012. Design/methodology/approach: The work systematically analyzes descriptive information, methods, and designs in these studies, and their…

Design Architecture of field-effect transistor with back gate electrode for biosensor application

NASA Astrophysics Data System (ADS)

Fathil, M. F. M.; Arshad, M. K. Md.; Hashim, U.; Ruslinda, A. R.; Gopinath, Subash C. B.; M. Nuzaihan M., N.; Ayub, R. M.; Adzhri, R.; Zaki, M.; Azman, A. H.

2016-07-01

This paper presents the preparation method of photolithography chrome mask design used in fabrication process of field-effect transistor with back gate biasing based biosensor. Initially, the chrome masks are designed by studying the process flow of the biosensor fabrication, followed by drawing of the actual chrome mask using the AutoCAD software. The overall width and length of the device is optimized at 16 mm and 16 mm, respectively. Fabrication processes of the biosensor required five chrome masks, which included source and drain formation mask, the back gate area formation mask, electrode formation mask, front gate area formation mask, and passivation area formation mask. The complete chrome masks design will be sent for chrome mask fabrication and for future use in biosensor fabrication.

Optical cylinder designs to increase the field of vision in the osteo-odonto-keratoprosthesis.

PubMed

Hull, C C; Liu, C S; Sciscio, A; Eleftheriadis, H; Herold, J

2000-12-01

The single optical cylinders used in the osteo-odonto-keratoprosthesis (OOKP) are known to produce very small visual fields. Values of 40 degrees are typically quoted. The purpose of this paper is to present designs for new optical cylinders that significantly increase the field of view and therefore improve the visual rehabilitation of patients having an OOKP. Computer ray-tracing techniques were used to design and analyse improved one- and two-piece optical cylinders made from polymethyl methacrylate. All designs were required to have a potential visual acuity of 6/6 before consideration was given to the visual field and optimising off-axis image quality. Aspheric surfaces were used where this significantly improved off-axis image quality. Single optical cylinders, with increased posterior cylinder (intraocular) diameters, gave an increase in the theoretical visual field of 18% (from 76 degrees to 90 degrees) over current designs. Two-piece designs based on an inverted telephoto principle gave theoretical field angles over 120 degrees. Aspheric surfaces were shown to improve the off-axis image quality while maintaining a potential visual acuity of at least 6/6. This may well increase the measured visual field by improving the retinal illuminance off-axis. Results demonstrate that it is possible to significantly increase the theoretical maximum visual field through OOKP optical cylinders. Such designs will improve the visual rehabilitation of patients undergoing this procedure.

Field studies in pesticide registration: questioning the answers.

PubMed

Montforts, Mark H M M; de Jong, Frank M W

2007-01-01

The principal conclusion of a workshop in October 2005 at RIVM (Bilthoven, The Netherlands) on the assessment of field studies with pesticides for authorization is that the lack of a definition of acceptability of effects is recognized as a problem by all stakeholders: Industry, risk assessors, and regulators. Because of this lack of definition in the legislation, it is unclear what critical effect values should be assessed in field studies. Despite the extensive documentation on field study performance, the decision making is not based on justifiable scientific opinions or publicly shared values but on technical limitations of the test design instead. In the workshop, research was identified that should result in a scientific basis for value judgments applied in decision making.

Early results from Magsat. [studies of near-earth magnetic fields

NASA Technical Reports Server (NTRS)

Langel, R. A.; Estes, R. H.; Mayhew, M. A.

1981-01-01

Papers presented at the May 27, 1981 meeting of the American Geophysical Union concerning early results from the Magsat satellite program, which was designed to study the near-earth magnetic fields originating in the core and lithosphere, are discussed. The satellite was launched on October 30, 1979 into a sun-synchronous (twilight) orbit, and re-entered the atmosphere on June 11, 1980. Instruments carried included a cesium vapor magnetometer to measure field magnitudes, a fluxgate magnetometer to measure field components and an optical system to measure fluxgate magnetometer orientation. Early results concerned spherical harmonic models, fields due to ionospheric and magnetospheric currents, the identification and interpretation of fields from lithospheric sources. The preliminary results confirm the possibility of separating the measured field into core, crustal and external components, and represent significant developments in analytical techniques in main-field modelling and the physics of the field sources.

Super-Compact Laser

NASA Technical Reports Server (NTRS)

1997-01-01

Microcosm, Inc. produced the portable Farfield-2 laser for field applications that require high power pulsed illumination. The compact design was conceived through research at Goddard Space Flight Center on laser instruments for space missions to carry out geoscience studies of Earth. An exclusive license to the key NASA patent for the compact laser design was assigned to Microcosm. The FarField-2 is ideal for field applications, has low power consumption, does not need water cooling or gas supplies, and produces nearly ideal beam quality. The properties of the laser also make it effective over long distances, which is one reason why NASA developed the technology for laser altimeters that can be toted aboard spacecraft. Applications for the FarField-2 include medicine, biology, and materials science and processing, as well as diamond marking, semiconductor line-cutting, chromosome surgery, and fluorescence microscopy.

A Tabletop Persistent-Mode, Liquid-Helium-Free, 1.5-T/90-mm MgB2 “Finger” MRI Magnet for Osteoporosis Screening: Two Design Options

PubMed Central

Park, Dongkeun; Bascuñán, Juan; Michael, Philip C.; Iwasa, Yukikazu

2017-01-01

In this paper we present two design options for a tabletop liquid-helium-free, persistent-mode 1.5-T/90-mm MgB2 “finger” MRI magnet for osteoporosis screening. Both designs, one with and the other without an iron yoke, satisfy the following criteria: 1) 1.5-T center field with a 90-mm room-temperature bore for a finger to be placed at the magnet center; 2) spatial field homogeneity of <5 ppm over a 20-mm diameter of spherical volume (DSV); 3) persistent-mode operation with temporal stability of <0.1 ppm/hr; 4) liquid-helium-free operation; 5) 5-gauss fringe field radius of <50 cm from the magnet center; and 6) small and light enough for placement on an exam table. Although the magnet is designed to operate nominally at 10 K, maintained by a cryocooler, it has a 5-K temperature margin to keep its 1.5-T persistent field up to 15 K. The magnet will be immersed in a volume of solid nitrogen (SN2) that provides additional thermal mass when the cryocooler is switched off to provide a vibration-free measurement environment. The SN2 enables the magnet to maintain its persistent field over a period of time sufficient for quiescent measurement, while still limiting the magnet operating temperature to ≤15 K. We discuss first pros and cons of each design, and then further studies of our proposed MgB2 finger MRI magnet. PMID:29456437

A Tabletop Persistent-Mode, Liquid-Helium-Free, 1.5-T/90-mm MgB2 "Finger" MRI Magnet for Osteoporosis Screening: Two Design Options.

PubMed

Park, Dongkeun; Bascuñán, Juan; Michael, Philip C; Iwasa, Yukikazu

2018-04-01

In this paper we present two design options for a tabletop liquid-helium-free, persistent-mode 1.5-T/90-mm MgB 2 "finger" MRI magnet for osteoporosis screening. Both designs, one with and the other without an iron yoke, satisfy the following criteria: 1) 1.5-T center field with a 90-mm room-temperature bore for a finger to be placed at the magnet center; 2) spatial field homogeneity of <5 ppm over a 20-mm diameter of spherical volume (DSV); 3) persistent-mode operation with temporal stability of <0.1 ppm/hr; 4) liquid-helium-free operation; 5) 5-gauss fringe field radius of <50 cm from the magnet center; and 6) small and light enough for placement on an exam table. Although the magnet is designed to operate nominally at 10 K, maintained by a cryocooler, it has a 5-K temperature margin to keep its 1.5-T persistent field up to 15 K. The magnet will be immersed in a volume of solid nitrogen (SN 2 ) that provides additional thermal mass when the cryocooler is switched off to provide a vibration-free measurement environment. The SN 2 enables the magnet to maintain its persistent field over a period of time sufficient for quiescent measurement, while still limiting the magnet operating temperature to ≤15 K. We discuss first pros and cons of each design, and then further studies of our proposed MgB 2 finger MRI magnet.

Student-guided field based investigations of microplastic contamination in urban waterways as a tool to introduce environmental science students to scientific inquiry

NASA Astrophysics Data System (ADS)

Pondell, C.

2016-12-01

Microplastic pollution is becoming an increasing concern in oceanographic and environmental studies, and offers an opportunity to engage undergraduate students in environmental research using a highly relevant field of investigation. For instance, a majority of environmental science majors not only know about the Great Pacific Garbage Patch, but can also list off several statistics about its size and impact on marine life. Building on this enthusiasm for understanding the impact of microplastics on the environment, a laboratory class was designed to introduce environmental science majors to the rigors of scientific investigation using microplastic pollution in urban waterways as the focus of their laboratory experience. Over a seven-week period, students worked in small groups to design an experiment, collect samples in the field, analyze the samples in the lab, and present their findings in a university-wide forum. Their research questions focused on developing a better understanding of the transportation and fate of microplastics in the urban waterways of Washington, D.C. This presentation will explore the benefits and challenges associated with a student guided field study for environmental science undergraduates, and will describe results and student feedback from their urban microplastic field study.

Standardization of Course Plan and Design of Objective Structured Field Examination (OSFE) for the Assessment of Pharm.D. Student’s Community Pharmacy Clerkship Skills

PubMed Central

Monajjemzadeh, Farnaz; Shokri, Javad; Mohajel Nayebi, Ali Reza; Nemati, Mahboob; Azarmi, Yadollah; Charkhpour, Mohammad; Najafi, Moslem

2014-01-01

Purpose: This study was aimed to design Objective Structured Field Examination (OSFE) and also standardize the course plan of community pharmacy clerkship at Pharmacy Faculty of Tabriz University of Medical Sciences (Iran). Methods: The study was composed of several stages including; evaluation of the old program, standardization and implementation of the new course plan, design and implementation of OSFE, and finally results evaluation. Results: Lack of a fair final assessment protocol and proper organized educating system in various fields of community pharmacy clerkship skills were assigned as the main weaknesses of the old program. Educational priorities were determined and student’s feedback was assessed to design the new curriculum consisting of sessions to fulfill a 60-hour training course. More than 70% of the students were satisfied and successfulness and efficiency of the new clerkship program was significantly greater than the old program (P<0.05). In addition, they believed that OSFE was a suitable testing method. Conclusion: The defined course plan was successfully improved different skills of the students and OSFE was concluded as a proper performance based assessment method. This is easily adoptable by pharmacy faculties to improve the educational outcomes of the clerkship course. PMID:24511477

First Studies for the Development of Computational Tools for the Design of Liquid Metal Electromagnetic Pumps

DOE Office of Scientific and Technical Information (OSTI.GOV)

Maidana, Carlos O.; Nieminen, Juha E.

Liquid alloy systems have a high degree of thermal conductivity, far superior to ordinary nonmetallic liquids and inherent high densities and electrical conductivities. This results in the use of these materials for specific heat conducting and dissipation applications for the nuclear and space sectors. Uniquely, they can be used to conduct heat and electricity between nonmetallic and metallic surfaces. The motion of liquid metals in strong magnetic fields generally induces electric currents, which, while interacting with the magnetic field, produce electromagnetic forces. Electromagnetic pumps exploit the fact that liquid metals are conducting fluids capable of carrying currents, which is amore » source of electromagnetic fields useful for pumping and diagnostics. The coupling between the electromagnetics and thermo-fluid mechanical phenomena and the determination of its geometry and electrical configuration, gives rise to complex engineering magnetohydrodynamics problems. The development of tools to model, characterize, design, and build liquid metal thermomagnetic systems for space, nuclear, and industrial applications are of primordial importance and represent a cross-cutting technology that can provide unique design and development capabilities as well as a better understanding of the physics behind the magneto-hydrodynamics of liquid metals. Here, first studies for the development of computational tools for the design of liquid metal electromagnetic pumps are discussed.« less

First Studies for the Development of Computational Tools for the Design of Liquid Metal Electromagnetic Pumps

DOE PAGES

Maidana, Carlos O.; Nieminen, Juha E.

2017-02-01

Liquid alloy systems have a high degree of thermal conductivity, far superior to ordinary nonmetallic liquids and inherent high densities and electrical conductivities. This results in the use of these materials for specific heat conducting and dissipation applications for the nuclear and space sectors. Uniquely, they can be used to conduct heat and electricity between nonmetallic and metallic surfaces. The motion of liquid metals in strong magnetic fields generally induces electric currents, which, while interacting with the magnetic field, produce electromagnetic forces. Electromagnetic pumps exploit the fact that liquid metals are conducting fluids capable of carrying currents, which is amore » source of electromagnetic fields useful for pumping and diagnostics. The coupling between the electromagnetics and thermo-fluid mechanical phenomena and the determination of its geometry and electrical configuration, gives rise to complex engineering magnetohydrodynamics problems. The development of tools to model, characterize, design, and build liquid metal thermomagnetic systems for space, nuclear, and industrial applications are of primordial importance and represent a cross-cutting technology that can provide unique design and development capabilities as well as a better understanding of the physics behind the magneto-hydrodynamics of liquid metals. Here, first studies for the development of computational tools for the design of liquid metal electromagnetic pumps are discussed.« less

Coaxial cable sensors and sensing instrument for crack detection in bridge structures--phase I : field qualification/validation planning.

DOT National Transportation Integrated Search

2009-11-01

The objectives of this study are to pre-test analyze a decommissioned reinforced concrete (RC) bridge that is selected in consultation with the New York State Department of Transportation (NYSDOT), and design and plan the field tests of the bridge fo...

Using Artificial Nests to Study Nest Predation in Birds

ERIC Educational Resources Information Center

Belthoff, James R.

2005-01-01

A simple and effective field exercise that demonstrates factors affecting predation on bird nests is described. With instructor guidance, students in high school biology or college-level biology, ecology, animal behavior, wildlife management or ornithology laboratory courses can collaborate to design field experiments related to nest depredation.

Creating Dissonance in Pre-Service Teachers' Field Experiences

ERIC Educational Resources Information Center

Eisenhardt, Sara; Besnoy, Kevin; Steele, Emily

2012-01-01

The study is practical in nature and addresses the call for investigating effective aspects of field experiences in teacher preparation. The authors designed a framework of assignments requiring the pre-service teachers to collect data about two diverse elementary students in their assigned elementary classroom during the twelve weeks of their…

Structural and Conceptual Interweaving of Mathematics Methods Coursework and Field Practica

ERIC Educational Resources Information Center

Bahr, Damon L.; Monroe, Eula Ewing; Eggett, Dennis

2014-01-01

This paper describes a study of observed relationships between the design of a preservice elementary mathematics methods course with accompanying field practicum and changes in the extent to which participating prospective teachers identified themselves with the mathematics reform movement after becoming practicing teachers. The curriculum of the…

DESIGN OF SUPERCONDUCTING COMBINED FUNCTION MAGNETS FOR THE 50 GEV PROTON BEAM LINE FOR THE J-PARC NEUTRINO EXPERIMENT.

DOE Office of Scientific and Technical Information (OSTI.GOV)

WANDERER,P.; ET AL.

2003-06-15

Superconducting combined function magnets will be utilized for the 50GeV-750kW proton beam line for the J-PARC neutrino experiment and an R and D program has been launched at KEK. The magnet is designed to provide a combined function with a dipole field of 2.59 T and a quadrupole field of 18.7 T/m in a coil aperture of 173.4 mm. A single layer coil is proposed to reduce the fabrication cost and the coil arrangement in the 2-D cross-section results in left-right asymmetry. This paper reports the design study of the magnet.

RF Design of a High Average Beam-Power SRF Electron Source

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sipahi, Nihan; Biedron, Sandra; Gonin, Ivan

2016-06-01

There is a significant interest in developing high-average power electron sources, particularly in the area of electron sources integrated with Superconducting Radio Frequency (SRF) systems. For these systems, the electron gun and cathode parts are critical components for stable intensity and high-average powers. In this initial design study, we will present the design of a 9-cell accelerator cavity having a frequency of 1.3 GHz and the corresponding field optimization studies.

Optimized magnet for a 250 MeV proton radiotherapy cyclotron

NASA Astrophysics Data System (ADS)

Kim, J.; Blosser, H.

2001-12-01

The NSCL accelerator group in 1993 carried out an extensive design study [1] for a K250 superconducting cyclotron for advanced cancer therapy. A private company ACCEL now offers cyclotrons based on this study on a commercial basis, and actual construction of a first such cyclotron is likely in the near future. In view of this, further optimization of the design of the superconducting magnet is currently underway. The configuration of the cyclotron has many similarities with previous NSCL-built superconducting cyclotrons—notable differences are the peak average field of 3 T (required by the focusing limit for protons) vs the 5 tesla of other MSU designs, and the use of four sectors rather than three to avoid the νr=3/2 stopband. The further optimization of the magnetic design described here keys on using the true 3D magnetic field program to more precisely match the design to an optimized orbital frequency configuration and to explore reducing the amount of spiral in the hills which then shortens the linear length of the rf elements and therefore reduces capacity and power consumption.

33 CFR 273.14 - Planning procedures.

Code of Federal Regulations, 2011 CFR

2011-07-01

..., D.C. 20314 will be followed by further investigations. Normally, a detailed State design memorandum... information. Field surveys and office studies should be limited to minimum essentials for further detailed... include, but not be limited to, the information contained in Appendix B. (b) State design memorandum. When...

33 CFR 273.14 - Planning procedures.

Code of Federal Regulations, 2010 CFR

2010-07-01

..., D.C. 20314 will be followed by further investigations. Normally, a detailed State design memorandum... information. Field surveys and office studies should be limited to minimum essentials for further detailed... include, but not be limited to, the information contained in Appendix B. (b) State design memorandum. When...

33 CFR 273.14 - Planning procedures.

Code of Federal Regulations, 2013 CFR

2013-07-01

..., D.C. 20314 will be followed by further investigations. Normally, a detailed State design memorandum... information. Field surveys and office studies should be limited to minimum essentials for further detailed... include, but not be limited to, the information contained in Appendix B. (b) State design memorandum. When...

33 CFR 273.14 - Planning procedures.

Code of Federal Regulations, 2012 CFR

2012-07-01

..., D.C. 20314 will be followed by further investigations. Normally, a detailed State design memorandum... information. Field surveys and office studies should be limited to minimum essentials for further detailed... include, but not be limited to, the information contained in Appendix B. (b) State design memorandum. When...

33 CFR 273.14 - Planning procedures.

Code of Federal Regulations, 2014 CFR

2014-07-01

..., D.C. 20314 will be followed by further investigations. Normally, a detailed State design memorandum... information. Field surveys and office studies should be limited to minimum essentials for further detailed... include, but not be limited to, the information contained in appendix B. (b) State design memorandum. When...

Gathering system optimization in a gas field with commingled flowlines

DOE Office of Scientific and Technical Information (OSTI.GOV)

Soetedja, V.; Harun, A.F.

1995-10-01

Badak Field, located in East Kalimantan, Indonesia, is a giant onshore gas field with 181 wells and total gas deliverability of 1.3 billion standard cubic feet (BSCF) per day. In many cases, gas from more than one well is commingled in the same flowline. This study concludes that commingling flowlines has been extremely cost effective over the life of the field. However, good initial design is required to anticipate future reservoir depletion and recompletions in order to achieve the best economic efficiency.

Design progress of the solar UV-Vis-IR telescope (SUVIT) aboard SOLAR-C

NASA Astrophysics Data System (ADS)

Katsukawa, Y.; Ichimoto, K.; Suematsu, Y.; Hara, H.; Kano, R.; Shimizu, T.; Matsuzaki, K.

2013-09-01

We present a design progress of the Solar UV-Vis-IR Telescope (SUVIT) aboard the next Japanese solar mission SOLAR-C. SUVIT has an aperture diameter of ~1.4 m for achieving spectro-polarimetric observations with spatial and temporal resolution exceeding the Hinode Solar Optical Telescope (SOT). We have studied structural and thermal designs of the optical telescope as well as the optical interface between the telescope and the focal plane instruments. The focal plane instruments are installed into two packages, filtergraph and spectrograph packages. The spectropolarimeter is the instrument dedicated to accurate polarimetry in the three spectrum windows at 525 nm, 854 nm, and 1083 nm for observing magnetic fields at both the photospheric and chromospheric layers. We made optical design of the spectrograph accommodating the conventional slit spectrograph and the integral field unit (IFU) for two-dimensional coverage. We are running feasibility study of the IFU using fiber arrays consisting of rectangular cores.

Analytical and numerical study on cooling flow field designs performance of PEM fuel cell with variable heat flux

NASA Astrophysics Data System (ADS)

Afshari, Ebrahim; Ziaei-Rad, Masoud; Jahantigh, Nabi

2016-06-01

In PEM fuel cells, during electrochemical generation of electricity more than half of the chemical energy of hydrogen is converted to heat. This heat of reactions, if not exhausted properly, would impair the performance and durability of the cell. In general, large scale PEM fuel cells are cooled by liquid water that circulates through coolant flow channels formed in bipolar plates or in dedicated cooling plates. In this paper, a numerical method has been presented to study cooling and temperature distribution of a polymer membrane fuel cell stack. The heat flux on the cooling plate is variable. A three-dimensional model of fluid flow and heat transfer in cooling plates with 15 cm × 15 cm square area is considered and the performances of four different coolant flow field designs, parallel field and serpentine fields are compared in terms of maximum surface temperature, temperature uniformity and pressure drop characteristics. By comparing the results in two cases, the constant and variable heat flux, it is observed that applying constant heat flux instead of variable heat flux which is actually occurring in the fuel cells is not an accurate assumption. The numerical results indicated that the straight flow field model has temperature uniformity index and almost the same temperature difference with the serpentine models, while its pressure drop is less than all of the serpentine models. Another important advantage of this model is the much easier design and building than the spiral models.

The effects of field dependent/independent style awareness on learning strategies and outcomes in an instructional hypermedia module

NASA Astrophysics Data System (ADS)

Fyle, Clifford Omodele

The purpose of this study was to examine whether field-dependent/independent style awareness affects learning outcomes and learning strategies used in a hypermedia instructional module. Field-dependent/independent style was measured using the Global Embedded Figures Test. Style awareness meant that students were provided with information and explanations about their individual cognitive styles and the learning strategies that accommodate those styles. The study entailed examining students' achievement in a multiple-choice test and performance in a design task, and also their navigation patterns as they studied a science-oriented Webquest. The sample consisted of 149 eighth-grade students in 10 sections of a science class taught by two teachers in a public middle school. A two-group posttest-only design on one factor (style awareness) was used. Sixty-eight students in five sections of the class were assigned to the treatment group (field dependent/independent style awareness) while the other 81 students in five sections were assigned to the control group (no field dependent/independent style awareness). The study took place over a period of 6 days. On the first day, students in the treatment group were first tested and debriefed on their individual styles. Next, all students in both the treatment and control groups studied the hypermedia instructional module (Webquest) over a period of two days. On the fourth and fifth days students worked on the performance tasks, and on the sixth day students took the multiple-choice test and students in the control group were tested and debriefed on their individual styles. The findings indicate that style awareness significantly influenced the learning strategies of field-dependent students as they studied and carried out learning tasks in the Webquest. Field-dependent students with style awareness used hypertext links and navigated the menu sequentially a greater number of times than their counterparts with no style awareness. Correspondingly, there were no significant findings for field-independent students of the effects of style awareness on learning strategies. The findings also revealed significant differences in terms of style awareness and its interactions with achievement on the multiple-choice test. Both field-dependent and field-independent students with style awareness achieved higher scores than their counterparts who received no style awareness. There were however no significant findings with respect to the effects of style awareness on performance on the design task. Overall this study demonstrated that providing middle-school students with cognitive-style awareness training can improve both their academic performance as well as enable them to adopt more effective learning strategies when learning in hypermedia environments.

Intervention studies to foster resilience - A systematic review and proposal for a resilience framework in future intervention studies.

PubMed

Chmitorz, A; Kunzler, A; Helmreich, I; Tüscher, O; Kalisch, R; Kubiak, T; Wessa, M; Lieb, K

2018-02-01

Psychological resilience refers to the phenomenon that many people are able to adapt to the challenges of life and maintain mental health despite exposure to adversity. This has stimulated research on training programs to foster psychological resilience. We evaluated concepts, methods and designs of 43 randomized controlled trials published between 1979 and 2014 which assessed the efficacy of such training programs and propose standards for future intervention research based on recent developments in the field. We found that concepts, methods and designs in current resilience intervention studies are of limited use to properly assess efficacy of interventions to foster resilience. Major problems are the use of definitions of resilience as trait or a composite of resilience factors, the use of unsuited assessment instruments, and inappropriate study designs. To overcome these challenges, we propose 1) an outcome-oriented definition of resilience, 2) an outcome-oriented assessment of resilience as change in mental health in relation to stressor load, and 3) methodological standards for suitable study designs of future intervention studies. Our proposals may contribute to an improved quality of resilience intervention studies and may stimulate further progress in this growing research field. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Woman Friendly Mosque, Features and Facilities: A Case Study on Masjid Sultan Ibrahim, Universiti Tun Hussein Onn Malaysia

NASA Astrophysics Data System (ADS)

Suratkon, A.; Salam, N. N. Abd; Rahmat, M. H.; Arhan, A. S. Mohd; Wahab, I. Abd; Ghaffar, S. A.

2017-12-01

Mosque has gone through a long and complex development throughout the Muslim’s history which involved the interrelation between its functions and its design. During the process, many aspects of its design were reconfigured including the female facilities in the mosque. In Malaysia, there is a progressive movement to transform the roles and functions of the mosque from exclusive place for prayers and seclusion to a community center. Nevertheless, there are still a numbers of muslim women voices their frustration towards the facilities provided to them in the mosque. Indirectly, this has discourage participation of women in the mosque. The objective of this paper is to investigate the opinions and needs of muslim women in a mosque and to propose appropriate features and facilities for a female-friendly mosque. The study explored through a field observation and a set of questionnaires, which involves a case study of Masjid Sultan Ibrahim in Universiti Tun Hussein Onn Malaysia. The field observation was carried out to analyze its current conditions, facilities, design and features. On the other hand, a set of questionnaire was distributed to the women visitors who were mainly students and staffs as to get their insight on this issue. From the field observation and the survey distributed, it was clearly seen that the facilities provided for the female users were still not up to the standard of a ‘women-friendly mosque’. Some proposals were provided to improve on the current condition and to be taken into consideration by future designers in designing a mosque.

Variable-speed Generators with Flux Weakening

NASA Technical Reports Server (NTRS)

Fardoun, A. A.; Fuchs, E. F.; Carlin, P. W.

1993-01-01

A cost-competitive, permanent-magnet 20 kW generator is designed such that the following criteria are satisfied: an (over) load capability of at least 30 kW over the entire speed range of 60-120 rpm, generator weight of about 550 lbs with a maximum radial stator flux density of 0.82 T at low speed, unity power factor operation, acceptably small synchronous reactances and operation without a gear box. To justify this final design four different generator designs are investigated: the first two designs are studied to obtain a speed range from 20 to 200 rpm employing rotor field weakening, and the latter two are investigated to obtain a maximum speed range of 40 to 160 rpm based on field weakening via the stator excitation. The generator reactances and induced voltages are computed using finite element/difference solutions. Generator losses and efficiencies are presented for all four designs at rated temperature of Tr=120C.

Experimental and Study Design Considerations for Uncovering Oncometabolites.

PubMed

Haznadar, Majda; Mathé, Ewy A

2017-01-01

Metabolomics as a field has gained attention due to its potential for biomarker discovery, namely because it directly reflects disease phenotype and is the downstream effect of posttranslational modifications. The field provides a "top-down," integrated view of biochemistry in complex organisms, as opposed to the traditional "bottom-up" approach that aims to analyze networks of interactions between genes, proteins and metabolites. It also allows for the detection of thousands of endogenous metabolites in various clinical biospecimens in a high-throughput manner, including tissue and biofluids such as blood and urine. Of note, because biological fluid samples can be collected relatively easily, the time-dependent fluctuations of metabolites can be readily studied in detail.In this chapter, we aim to provide an overview of (1) analytical methods that are currently employed in the field, and (2) study design concepts that should be considered prior to conducting high-throughput metabolomics studies. While widely applicable, the concepts presented here are namely applicable to high-throughput untargeted studies that aim to search for metabolite biomarkers that are associated with a particular human disease.

Beam dynamics and electromagnetic studies of a 3 MeV, 325 MHz radio frequency quadrupole accelerator

NASA Astrophysics Data System (ADS)

Gaur, Rahul; Kumar, Vinit

2018-05-01

We present the beam dynamics and electromagnetic studies of a 3 MeV, 325 MHz H- radio frequency quadrupole (RFQ) accelerator for the proposed Indian Spallation Neutron Source project. We have followed a design approach, where the emittance growth and the losses are minimized by keeping the tune depression ratio larger than 0.5. The transverse cross-section of RFQ is designed at a frequency lower than the operating frequency, so that the tuners have their nominal position inside the RFQ cavity. This has resulted in an improvement of the tuning range, and the efficiency of tuners to correct the field errors in the RFQ. The vane-tip modulations have been modelled in CST-MWS code, and its effect on the field flatness and the resonant frequency has been studied. The deterioration in the field flatness due to vane-tip modulations is reduced to an acceptable level with the help of tuners. Details of the error study and the higher order mode study along with mode stabilization technique are also described in the paper.

TU-H-BRA-07: Design, Construction, and Installation of An Experimental Beam Line for the Development of MRI-Linac Compatible Electron Accelerator

DOE Office of Scientific and Technical Information (OSTI.GOV)

Whelan, B; Keall, P; Holloway, L

Purpose: MRI guided radiation therapy (MRIgRT) is a rapidly growing field; however, Linac operation in MRI fringe fields represents an ongoing challenge. We have previously shown in-silico that Linacs could be redesigned to function in the in-line orientation with no magnetic shielding by adopting an RF-gun configuration. Other authors have also published insilico studies of Linac operation in magnetic fields; however to date no experimental validation data is published. This work details the design, construction, and installation of an experimental beam line to validate our in-silico results. Methods: An RF-gun comprising 1.5 accelerating cells and capable of generating electron energiesmore » up to 3.2MeV is used. The experimental apparatus was designed to monitor both beam current (toroid current monitor), spot size (two phosphor screens with viewports), and generate peak magnetic fields of at least 1000G (three variable current electromagnetic coils). Thermal FEM simulations were developed to ensure coil temperature remained within 100degC. Other design considerations included beam disposal, vacuum maintenance, radiation shielding, earthquake safety, and machine protection interlocks. Results: The beam line has been designed, built, and installed in a radiation shielded bunker. Water cooling, power supplies, thermo-couples, cameras, and radiation shielding have been successfully connected and tested. Interlock testing, vacuum processing, and RF processing have been successfully completed. The first beam on is expected within weeks. The coil heating simulations show that with care, peak fields of up to 1200G (320G at cathode) can be produced using 40A current, which is well within the fields expected for MRI-Linac systems. The maximum coil temperature at this current was 84degC after 6 minutes. Conclusion: An experimental beam line has been constructed and installed at SLAC in order to experimentally characterise RF gun performance in in-line magnetic fields, validate in-silico design work, and provide the first published experimental data relating to accelerator functionality for MRIgRT.« less

Relation between experimental and non-experimental study designs. HB vaccines: a case study.

PubMed

Jefferson, T; Demicheli, V

1999-01-01

To examine the relation between experimental and non-experimental study design in vaccinology. Assessment of each study design's capability of testing four aspects of vaccine performance, namely immunogenicity (the capacity to stimulate the immune system), duration of immunity conferred, incidence and seriousness of side effects, and number of infections prevented by vaccination. Experimental and non-experimental studies on hepatitis B (HB) vaccines in the Cochrane Vaccines Field Database. Experimental and non-experimental vaccine study designs are frequently complementary but some aspects of vaccine quality can only be assessed by one of the types of study. More work needs to be done on the relation between study quality and its significance in terms of effect size.

Cosmic Dawn Intensity Mapper (CDIM): Instrument and Mission Design

NASA Astrophysics Data System (ADS)

Unwin, Stephen C.; CDIM Team

2018-01-01

CDIM is the Cosmic Dawn Intensity Mapper, one of the probe-class missions currently under study for NASA. A detailed Report from the study will be submitted to NASA and for consideration by the Decadal Survey. The flight system will comprise a wide-field cryogenic telescope with a large focal plane array providing complete coverage from optical through mid-IR. The system will be deployed to L2 or Earth-trailing orbit, to provide a stable thermal environment and allow extended observations of fields selected to be cross-correlated with deep surveys in other wavebands. Spectra with will be measured for every point in each target field, using linear variable filters (LVFs). These filters eliminate the need for a spectrometer in the focal plane. Spectra are built up through simple imaging of a series of telescope pointings separated by small angular offsets. This poster presents the initial concept for the instrument and mission design.

A design study for a medium-scale field demonstration of the viscous barrier technology

DOE Office of Scientific and Technical Information (OSTI.GOV)

Moridis, G.; Yen, P.; Persoff, P.

1996-09-01

This report is the design study for a medium-scale field demonstration of Lawrence Berkeley National Laboratory`s new subsurface containment technology for waste isolation using a new generation of barrier liquids. The test site is located in central California in a quarry owned by the Los Banos Gravel Company in Los Banos, California, in heterogeneous unsaturated deposits of sand, silt, and -ravel typical of many of the and DOE cleanup sites and particularly analogous to the Hanford site. The coals of the field demonstration are (a) to demonstrate the ability to create a continuous subsurface barrier isolating a medium-scale volume (30more » ft long by 30 ft wide by 20 ft deep, i.e. 1/10th to 1/8th the size of a buried tank at the Hanford Reservation) in the subsurface, and (b) to demonstrate the continuity, performance, and integrity of the barrier.« less

Optical design for CETUS: a wide-field 1.5m aperture UV payload being studied for a NASA probe class mission study

NASA Astrophysics Data System (ADS)

Woodruff, Robert A.; Hull, Tony; Heap, Sara R.; Danchi, William; Kendrick, Stephen E.; Purves, Lloyd

2017-09-01

We are developing a NASA Headquarters selected Probe-class mission concept called the Cosmic Evolution Through UV Spectroscopy (CETUS) mission, which includes a 1.5-m aperture diameter large field-of-view (FOV) telescope optimized for UV imaging, multi-object spectroscopy, and point-source spectroscopy. The optical system includes a Three Mirror Anastigmatic (TMA) telescope that simultaneously feeds three separate scientific instruments: the near-UV (NUV) Multi-Object Spectrograph (MOS) with a next-generation Micro-Shutter Array (MSA); the two-channel camera covering the far-UV (FUV) and NUV spectrum; and the point-source spectrograph covering the FUV and NUV region with selectable R 40,000 echelle modes and R 2,000 first order modes. The optical system includes fine guidance sensors, wavefront sensing, and spectral and flat-field in-flight calibration sources. This paper will describe the current optical design of CETUS.

Optical design for CETUS: a wide-field 1.5m aperture UV payload being studied for a NASA probe class mission study

NASA Astrophysics Data System (ADS)

Woodruff, Robert; Robert Woodruff, Goddard Space Flight Center, Kendrick Optical Consulting

2018-01-01

We are developing a NASA Headquarters selected Probe-class mission concept called the Cosmic Evolution Through UV Spectroscopy (CETUS) mission, which includes a 1.5-m aperture diameter large field-of-view (FOV) telescope optimized for UV imaging, multi-object spectroscopy, and point-source spectroscopy. The optical system includes a Three Mirror Anastigmatic (TMA) telescope that simultaneously feeds three separate scientific instruments: the near-UV (NUV) Multi-Object Spectrograph (MOS) with a next-generation Micro-Shutter Array (MSA); the two-channel camera covering the far-UV (FUV) and NUV spectrum; and the point-source spectrograph covering the FUV and NUV region with selectable R~ 40,000 echelle modes and R~ 2,000 first order modes. The optical system includes fine guidance sensors, wavefront sensing, and spectral and flat-field in-flight calibration sources. This paper will describe the current optical design of CETUS.

Visual analytics as a translational cognitive science.

PubMed

Fisher, Brian; Green, Tera Marie; Arias-Hernández, Richard

2011-07-01

Visual analytics is a new interdisciplinary field of study that calls for a more structured scientific approach to understanding the effects of interaction with complex graphical displays on human cognitive processes. Its primary goal is to support the design and evaluation of graphical information systems that better support cognitive processes in areas as diverse as scientific research and emergency management. The methodologies that make up this new field are as yet ill defined. This paper proposes a pathway for development of visual analytics as a translational cognitive science that bridges fundamental research in human/computer cognitive systems and design and evaluation of information systems in situ. Achieving this goal will require the development of enhanced field methods for conceptual decomposition of human/computer cognitive systems that maps onto laboratory studies, and improved methods for conducting laboratory investigations that might better map onto real-world cognitive processes in technology-rich environments. Copyright © 2011 Cognitive Science Society, Inc.

The Role of Emotions in Fieldwork: A Self-Study of Family Research in a Corrections Setting

ERIC Educational Resources Information Center

Arditti, Joyce A.; Joest, Karen S.; Lambert-Shute, Jennifer; Walker, Latanya

2010-01-01

In this study, we document a reflexive process via bracketing techniques and the development of a conceptual map in order to better understand how emotions that arise in the field can inform research design, implementation, and results. We conducted a content analysis of field notes written by a team of researchers who administered an interview to…

High Fidelity Modeling of Field Reversed Configuration (FRC) Thrusters

DTIC Science & Technology

2016-06-01

space propulsion . This effort consists of numerical model development, physical model development, and systematic studies of the non-linear plasma...studies of the physical characteristics of Field Reversed Configuration (FRC) plasma for advanced space propulsion . This effort consists of numerical...FRCs for propulsion application. Two of the most advanced designs are based on the theta-pinch formation and the RMF formation mechanism, which

Advancing Higher Education as a Field of Study: In Quest of Doctoral Degree Guidelines--Commemorating 120 Years of Excellence

ERIC Educational Resources Information Center

Freeman, Sydney, Jr., Ed.; Hagedorn, Linda Serra, Ed.; Goodchild, Lester, Ed.; Wright, Dianne, Ed.

2013-01-01

Where is higher education as a field of study going in this century? How will higher education program leaders design and sustain their degree programs' vitality in the face of perennial challenges from inside and outside the academy? While in 1979 the Council for the Advancement of Standards in Higher Education (CAS) defined standards for student…

A Field Study of a Rural Ungraded Primary School with a Statistical Analysis of Reading Achievement and Personality Adjustment.

ERIC Educational Resources Information Center

McCoy, Edwardine Cordell

The purpose of this field study was to develop a rural ungraded primary school with an accompanying design and appropriate materials for use by educators interested in this innovation. Pretests and posttests measured the effects of ungradedness on the reading achievement and personality development of the 177 students. Implemented by a $50,000…

Salinity Changes in a Tidal River. A Learning Experience for Coastal and Oceanic Awareness Studies, No. 308. [Project COAST].

ERIC Educational Resources Information Center

Delaware Univ., Newark. Coll. of Education.

The materials in this packet are designed to aid teachers in the implementation of a science field studies unit concerning tidal rivers. The packet consists of the following: (1) background material for the teacher; (2) lab exercises; (3) field activities; and (4) classroom activities. The overall purpose of this packet is to provide information…

A Design-Based Research Case Study Documenting a Constructivist ID Process and Instructional Solution for a Cross-Cultural Workforce

ERIC Educational Resources Information Center

Tracey, Monica W.; Unger, Kelly L.

2012-01-01

As the need for instructing a globalized workforce increases, instructional designers must embrace the constraints and the opportunities these projects provide in order to move the field of cross-cultural instructional design (ID) forward. Cross-cultural projects offer multiple avenues for growth in ID practice, overcoming cultural barriers, and a…

Magnetic fields for transporting charged beams

DOE Office of Scientific and Technical Information (OSTI.GOV)

Parzen, G.

1976-01-01

The transport of charged particle beams requires magnetic fields that must be shaped correctly and very accurately. During the last 20 years or so, many studies have been made, both analytically and through the use of computer programs, of various magnetic shapes that have proved to be useful. Many of the results for magnetic field shapes can be applied equally well to electric field shapes. A report is given which gathers together the results that have more general significance and would be useful in designing a configuration to produce a desired magnetic field shape. The field shapes studied include themore » fields in dipoles, quadrupoles, sextupoles, octupoles, septum magnets, combined-function magnets, and electrostatic septums. Where possible, empirical formulas are proposed, based on computer and analytical studies and on magnetic field measurements. These empirical formulas are often easier to use than analytical formulas and often include effects that are difficult to compute analytically. In addition, results given in the form of tables and graphs serve as illustrative examples. The field shapes studied include uniform fields produced by window-frame magnets, C-magnets, H-magnets, and cosine magnets; linear fields produced by various types of quadrupoles; quadratic and cubic fields produced by sextupoles and octupoles; combinations of uniform and linear fields; and septum fields with sharp boundaries.« less

Reusable Launch Vehicle Tank/Intertank Sizing Trade Study

NASA Technical Reports Server (NTRS)

Dorsey, John T.; Myers, David E.; Martin, Carl J.

2000-01-01

A tank and intertank sizing tool that includes effects of major design drivers, and which allows parametric studies to be performed, has been developed and calibrated against independent representative results. Although additional design features, such as bulkheads and field joints, are not currently included in the process, the improved level of fidelity has allowed parametric studies to be performed which have resulted in understanding of key tank and intertank design drivers, design sensitivities, and definition of preferred design spaces. The sizing results demonstrated that there were many interactions between the configuration parameters of internal/external payload, vehicle fineness ratio (half body angle), fuel arrangement (LOX-forward/LOX-aft), number of tanks, and tank shape/arrangement (number of lobes).

Diffraction modeling of finite subband EFC probing on dark hole contrast with WFIRST-CGI shaped pupil coronagraph

NASA Astrophysics Data System (ADS)

Zhou, Hanying; Krist, John; Nemati, Bijan

2016-08-01

Current coronagraph instrument design (CGI), as a part of a proposed NASA WFIRST (Wide-Field InfraRed Survey Telescope) mission, allocates two subband filters per full science band in order to contain system complexity and cost. We present our detailed investigation results on the adequacy of such limited number of finite subband filters in achieving full band dark hole contrast with shaped pupil coronagraph. The study is based on diffraction propagation modeling with realistic WFIRST optics, where each subband's complex field estimation is obtained, using Electric Field Conjugation (EFC) wavefront sensing / control algorithm, from pairwise pupil plane deformable mirror (DM) probing and image plane intensity averaging of the resulting fields of multiple (subband) wavelengths. Multiple subband choices and probing and control strategies are explored, including standard subband probing; mixed wavelength and/or weighted Jacobian matrix; subband probing with intensity subtraction; and extended subband probing with intensity subtraction. Overall, the investigation shows that the achievable contrast with limited number of finite subband EFC probing is about 2 2.5x worse than the designed post-EFC contrast for current SPC design. The result suggests that for future shaped pupil design, slightly larger over intended full bandwidth should be considered if it will be used with limited subbands for probing.

Field-based education and indigenous knowledge: Essential components of geoscience education for native American communities

NASA Astrophysics Data System (ADS)

Riggs, Eric M.

2005-03-01

The purpose of this study is to propose a framework drawing on theoretical and empirical science education research that explains the common prominent field-based components of the handful of persistent and successful Earth science education programs designed for indigenous communities in North America. These programs are primarily designed for adult learners, either in a postsecondary or in a technical education setting and all include active collaboration between local indigenous communities and geoscientists from nearby universities. Successful Earth science curricula for indigenous learners share in common an explicit emphasis on outdoor education, a place and problem-based structure, and the explicit inclusion of traditional indigenous knowledge in the instruction. Programs sharing this basic design have proven successful and popular for a wide range of indigenous cultures across North America. We present an analysis of common field-based elements to yield insight into indigenous Earth science education. We provide an explanation for the success of this design based in research on field-based learning, Native American learning styles research, and theoretical and empirical research into the nature and structure of indigenous knowledge. We also provide future research directions that can test and further refine our understanding of best practices in indigenous Earth science education.

Investigation of Condensed Media in Weak Fields by the Method of Nuclear Magnetic Resonance

NASA Astrophysics Data System (ADS)

Davydov, V. V.; Myazin, N. S.; Dudkin, V. I.; Velichko, E. N.

2018-05-01

A compact design of a rapid-response nuclear magnetic spectrometer for investigation of condensed media in weak fields is reported. As a result of investigation of different condensed media, special features of recording a nuclear magnetic resonance (NMR) signal in a weak magnetic field from a small volume of the medium under study are established. For the first time the NMR absorption spectra of condensed media in a weak field are collected. Based on the results of experimental studies, the potential of using a compact NMR-spectrometer for condensed media monitoring in a rapid response mode is determined.

Design of illumination system in ring field capsule endoscope

NASA Astrophysics Data System (ADS)

Jeng, Wei-De; Mang, Ou-Yang; Chen, Yu-Ta; Wu, Ying-Yi

2011-03-01

This paper is researching about the illumination system in ring field capsule endoscope. It is difficult to obtain the uniform illumination on the observed object because the light intensity of LED will be changed along its angular displacement and same as luminous intensity distribution curve. So we use the optical design software which is Advanced Systems Analysis Program (ASAP) to build a photometric model for the optimal design of LED illumination system in ring field capsule endoscope. In this paper, the optimal design of illumination uniformity in the ring field capsule endoscope is from origin 0.128 up to optimum 0.603 and it would advance the image quality of ring field capsule endoscope greatly.

Usability engineering for augmented reality: employing user-based studies to inform design.

PubMed

Gabbard, Joseph L; Swan, J Edward

2008-01-01

A major challenge, and thus opportunity, in the field of human-computer interaction and specifically usability engineering is designing effective user interfaces for emerging technologies that have no established design guidelines or interaction metaphors or introduce completely new ways for users to perceive and interact with technology and the world around them. Clearly, augmented reality is one such emerging technology. We propose a usability engineering approach that employs user-based studies to inform design, by iteratively inserting a series of user-based studies into a traditional usability engineering lifecycle to better inform initial user interface designs. We present an exemplar user-based study conducted to gain insight into how users perceive text in outdoor augmented reality settings and to derive implications for design in outdoor augmented reality. We also describe lessons learned from our experiences conducting user-based studies as part of the design process.

Development of an Instrument for the Measurement of Leadership Commitment to Organizational Process

ERIC Educational Resources Information Center

Hylton, Peter D.

2013-01-01

The purpose of this research study was to create a new instrument designed to examine the commitment of an organization's leadership to following organizational processes, as measured by stakeholder perceptions. This instrument was designed to aid in closure of a gap in the field of leadership studies relative to the impact that a leader's…

A preliminary optical design for the JANUS camera of ESA's space mission JUICE

NASA Astrophysics Data System (ADS)

Greggio, D.; Magrin, D.; Ragazzoni, R.; Munari, M.; Cremonese, G.; Bergomi, M.; Dima, M.; Farinato, J.; Marafatto, L.; Viotto, V.; Debei, S.; Della Corte, V.; Palumbo, P.; Hoffmann, H.; Jaumann, R.; Michaelis, H.; Schmitz, N.; Schipani, P.; Lara, L.

2014-08-01

The JANUS (Jovis, Amorum ac Natorum Undique Scrutator) will be the on board camera of the ESA JUICE satellite dedicated to the study of Jupiter and its moons, in particular Ganymede and Europa. This optical channel will provide surface maps with plate scale of 15 microrad/pixel with both narrow and broad band filters in the spectral range between 0.35 and 1.05 micrometers over a Field of View 1.72 × 1.29 degrees2. The current optical design is based on TMA design, with on-axis pupil and off-axis field of view. The optical stop is located at the secondary mirror providing an effective collecting area of 7854 mm2 (100 mm entrance pupil diameter) and allowing a simple internal baffling for first order straylight rejection. The nominal optical performances are almost limited by the diffraction and assure a nominal MTF better than 63% all over the whole Field of View. We describe here the optical design of the camera adopted as baseline together with the trade-off that has led us to this solution.

Beam dynamics validation of the Halbach Technology FFAG Cell for Cornell-BNL Energy Recovery Linac

DOE Office of Scientific and Technical Information (OSTI.GOV)

Meot, Francois; Tsoupas, N.; Brooks, S.

The Cornell-BNL Electron Test Accelerator (CBETA), a 150 MeV energy recovery linac (ERL) now in construction at Cornell, employs a fixed-field alternating gradient optics return loop: a single beam line comprised of FFAG cells, which accepts four recirculated energies. CBETA FFAG cell uses Halbach permanent magnet technology, its design studies have covered an extended period of time supported by extensive particle dynamics simulations using computed 3-D field map models. As a result, this approach is discussed, and illustrated here, based on the final stage in these beam dynamics studies, namely the validation of a ultimate, optimized design of the Halbachmore » cell.« less

Beam dynamics validation of the Halbach Technology FFAG Cell for Cornell-BNL Energy Recovery Linac

DOE PAGES

Meot, Francois; Tsoupas, N.; Brooks, S.; ...

2018-04-16

The Cornell-BNL Electron Test Accelerator (CBETA), a 150 MeV energy recovery linac (ERL) now in construction at Cornell, employs a fixed-field alternating gradient optics return loop: a single beam line comprised of FFAG cells, which accepts four recirculated energies. CBETA FFAG cell uses Halbach permanent magnet technology, its design studies have covered an extended period of time supported by extensive particle dynamics simulations using computed 3-D field map models. As a result, this approach is discussed, and illustrated here, based on the final stage in these beam dynamics studies, namely the validation of a ultimate, optimized design of the Halbachmore » cell.« less

[Not Available].

PubMed

Paturzo, Marco; Colaceci, Sofia; Clari, Marco; Mottola, Antonella; Alvaro, Rosaria; Vellone, Ercole

2016-01-01

. Mixed methods designs: an innovative methodological approach for nursing research. The mixed method research designs (MM) combine qualitative and quantitative approaches in the research process, in a single study or series of studies. Their use can provide a wider understanding of multifaceted phenomena. This article presents a general overview of the structure and design of MM to spread this approach in the Italian nursing research community. The MM designs most commonly used in the nursing field are the convergent parallel design, the sequential explanatory design, the exploratory sequential design and the embedded design. For each method a research example is presented. The use of MM can be an added value to improve clinical practices as, through the integration of qualitative and quantitative methods, researchers can better assess complex phenomena typical of nursing.

The GlueX central drift chamber: Design and performance

DOE Office of Scientific and Technical Information (OSTI.GOV)

Van Haarlem, Y; Barbosa, F; Dey, B

2010-10-01

Tests and studies concerning the design and performance of the GlueX Central Drift Chamber (CDC) are presented. A full-scale prototype was built to test and steer the mechanical and electronic design. Small scale prototypes were constructed to test for sagging and to do timing and resolution studies of the detector. These studies were used to choose the gas mixture and to program a Monte Carlo simulation that can predict the detector response in an external magnetic field. Particle identification and charge division possibilities were also investigated.

SUSTAINABLE ENERGY SYSTEMS DESIGN FOR A TRIBAL VILLAGE IN INDIA

EPA Science Inventory