Four Years of Farmer Experimentation on Soil Fertility in Tigray, Northern Ethiopia: Trends in Research Strategies

ERIC Educational Resources Information Center

Kraaijvanger, Richard G.; Veldkamp, Tom

2017-01-01

Purpose: This paper analyses research strategies followed by farmer groups in Tigray, that were involved in participatory experimentation. Understanding choices made by farmers in such experimentation processes is important to understand reasons why farmers in Tigray often hesitated to adopt recommended practices. Design/Methodology/Approach: A…

Impact of an inquiry unit on grade 4 students' science learning

NASA Astrophysics Data System (ADS)

Di Mauro, María Florencia; Furman, Melina

2016-09-01

This paper concerns the identification of teaching strategies that enhance the development of 4th grade students' experimental design skills at a public primary school in Argentina. Students' performance in the design of relevant experiments was evaluated before and after an eight-week intervention compared to a control group, as well as the persistence of this learning after eight months. The study involved a quasi-experimental longitudinal study with pre-test/post-test/delayed post-test measures, complemented with semi-structured interviews with randomly selected students. Our findings showed improvement in the experimental design skills as well as its sustainability among students working with the inquiry-based sequence. After the intervention, students were able to establish valid comparisons, propose pertinent designs and identify variables that should remain constant. Contrarily, students in the control group showed no improvement and continued to solve the posed problems based on prior beliefs. In summary, this paper shows evidence that implementing inquiry-based units involving problems set in cross-domain everyday situations that combine independent student work with teacher guidance significantly improves the development of scientific skills in real classroom contexts.

Musk as a Pheromone? Didactic Exercise.

ERIC Educational Resources Information Center

Bersted, Chris T.

A classroom/laboratory exercise has been used to introduce college students to factorial research designs, differentiate between interpretations for experimental and quasi-experimental variables, and exemplify application of laboratory research methods to test practical questions (advertising claims). The exercise involves having randomly divided…

2011 Nanoelectronic Devices for Defense & Security (NANO-DDS) Conference Held in Brooklyn, New York on August 29-September 1, 2011. Technical Program and Abstract Digest

DTIC Science & Technology

2011-08-01

challenges in new design methodologies . Particular examples involve an in-circuit functional timing testing of systems with millions of cores. I...TECHNIQUES Chair: Dwight Woolard, U.S. Army Research Office (ARO) 8:40-9:05 EXPERIMENTAL DESIGN OF SINGLE-CRYSTAL DNA FOR THZ SPECTROSCOPY...Detection Based Techniques EXPERIMENTAL DESIGN OF SINGLE-CRYSTAL DNA FOR THZ SPECTROSCOPY E. R. Brown, M.L. Norton, M. Rahman, W. Zhang Wright

Solar energy program evaluation: an introduction

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

deLeon, P.

The Program Evaluation Methodology provides an overview of the practice and methodology of program evaluation and defines more precisely the evaluation techniques and methodologies that would be most appropriate to government organizations which are actively involved in the research, development, and commercialization of solar energy systems. Formal evaluation cannot be treated as a single methodological approach for assessing a program. There are four basic types of evaluation designs - the pre-experimental design; the quasi-experimental design based on time series; the quasi-experimental design based on comparison groups; and the true experimental design. This report is organized to first introduce the rolemore » and issues of evaluation. This is to provide a set of issues to organize the subsequent sections detailing the national solar energy programs. Then, these two themes are integrated by examining the evaluation strategies and methodologies tailored to fit the particular needs of the various individual solar energy programs. (MCW)« less

Judy Netter | NREL

Science.gov Websites

thermochemical reactions (primarily hydrogen production), and recently Solar Power Tower Receiver design. She has . Her expertise involves the design and fabrication of prototype experimental equipment along with the programs and controls. CSP-related projects include the design of experiments and test equipment for

Overview of clinical research design.

PubMed

Hartung, Daniel M; Touchette, Daniel

2009-02-15

Basic concepts and terminology of clinical research design are presented for new clinical investigators. Clinical research, research involving human subjects, can be described as either observational or experimental. The findings of all clinical research can be threatened by issues of bias and confounding. Biases are systematic errors in how study subjects are selected or measured, which result in false inferences. Confounding is a distortion in findings that is attributable to mixing variable effects. Uncontrolled observation research is generally more prone to bias and confounding than experimental research. Observational research includes designs such as the cohort study, case-control study, and cross-sectional study, while experimental research typically involves a randomized controlled trial (RCT). The cohort study, which includes the RCT, defines subject allocation on the basis of exposure interest (e.g., drug, disease-management program) and follows the patients to assess the outcomes. The case-control study uses the primary outcome of interest (e.g., adverse event) to define subject allocation, and different exposures are assessed in a retrospective manner. Cross-sectional research evaluates both exposure and outcome concurrently. Each of these design methods possesses different strengths and weaknesses in answering research questions, as well as underlying many study subtypes. While experimental research is the strongest method for establishing causality, it can be difficult to accomplish under many scenarios. Observational clinical research offers many design alternatives that may be appropriate if planned and executed carefully.

Measuring and Advancing Experimental Design Ability in an Introductory Course without Altering Existing Lab Curriculum.

PubMed

Shanks, Ryan A; Robertson, Chuck L; Haygood, Christian S; Herdliksa, Anna M; Herdliska, Heather R; Lloyd, Steven A

2017-01-01

Introductory biology courses provide an important opportunity to prepare students for future courses, yet existing cookbook labs, although important in their own way, fail to provide many of the advantages of semester-long research experiences. Engaging, authentic research experiences aid biology students in meeting many learning goals. Therefore, overlaying a research experience onto the existing lab structure allows faculty to overcome barriers involving curricular change. Here we propose a working model for this overlay design in an introductory biology course and detail a means to conduct this lab with minimal increases in student and faculty workloads. Furthermore, we conducted exploratory factor analysis of the Experimental Design Ability Test (EDAT) and uncovered two latent factors which provide valid means to assess this overlay model's ability to increase advanced experimental design abilities. In a pre-test/post-test design, we demonstrate significant increases in both basic and advanced experimental design abilities in an experimental and comparison group. We measured significantly higher gains in advanced experimental design understanding in students in the experimental group. We believe this overlay model and EDAT factor analysis contribute a novel means to conduct and assess the effectiveness of authentic research experiences in an introductory course without major changes to the course curriculum and with minimal increases in faculty and student workloads.

Can Reflection Boost Competences Development in Organizations?

ERIC Educational Resources Information Center

Nansubuga, Florence; Munene, John C.; Ntayi, Joseph M.

2015-01-01

Purpose: The purpose of this paper is to examine the gaps in some existing competence frameworks and investigate the power of reflection on one's behavior to improve the process of the competences development. Design/methodology/approach: The authors used a correlational design and a quasi-experimental non-equivalent group design involving a…

Estimation of sample size and testing power (part 6).

PubMed

Hu, Liang-ping; Bao, Xiao-lei; Guan, Xue; Zhou, Shi-guo

2012-03-01

The design of one factor with k levels (k ≥ 3) refers to the research that only involves one experimental factor with k levels (k ≥ 3), and there is no arrangement for other important non-experimental factors. This paper introduces the estimation of sample size and testing power for quantitative data and qualitative data having a binary response variable with the design of one factor with k levels (k ≥ 3).

Controlled experiments for dense gas diffusion: Experimental design and execution, model comparison

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

Egami, R.; Bowen, J.; Coulombe, W.

1995-07-01

An experimental baseline CO2 release experiment at the DOE Spill Test Facility on the Nevada Test Site in Southern Nevada is described. This experiment was unique in its use of CO2 as a surrogate gas representative of a variety of specific chemicals. Introductory discussion places the experiment in historical perspective. CO2 was selected as a surrogate gas to provide a data base suitable for evaluation of model scenarios involving a variety of specific dense gases. The experiment design and setup are described, including design rationale and quality assurance methods employed. Resulting experimental data are summarized. Data usefulness is examined throughmore » a preliminary comparison of experimental results with simulations performed using the SLAV and DEGADIS dense gas models.« less

Andriy Zakutayev | NREL

Science.gov Websites

technologies using materials-by-design methods. The basic direction involves research on non-equilibrium doping in semiconductors Materials by Design and Materials Genome Non-equilibrium and metastable . 5, 1117 (2014) "Theoretical Prediction and Experimental Realization of New Stable Inorganic

Reflecting on Graphs: Attributes of Graph Choice and Construction Practices in Biology

ERIC Educational Resources Information Center

Angra, Aakanksha; Gardner, Stephanie M.

2017-01-01

Undergraduate biology education reform aims to engage students in scientific practices such as experimental design, experimentation, and data analysis and communication. Graphs are ubiquitous in the biological sciences, and creating effective graphical representations involves quantitative and disciplinary concepts and skills. Past studies…

Compact Heat Exchanger Design and Testing for Advanced Reactors and Advanced Power Cycles

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

Sun, Xiaodong; Zhang, Xiaoqin; Christensen, Richard

The goal of the proposed research is to demonstrate the thermal hydraulic performance of innovative surface geometries in compact heat exchangers used as intermediate heat exchangers (IHXs) and recuperators for the supercritical carbon dioxide (s-CO 2) Brayton cycle. Printed-circuit heat exchangers (PCHEs) are the primary compact heat exchangers of interest. The overall objectives are: To develop optimized PCHE designs for different working fluid combinations including helium to s-CO 2, liquid salt to s-CO 2, sodium to s-CO 2, and liquid salt to helium; To experimentally and numerically investigate thermal performance, thermal stress and failure mechanism of PCHEs under various transients;more » and To study diffusion bonding techniques for elevated-temperature alloys and examine post-test material integrity of the PCHEs. The project objectives were accomplished by defining and executing five different tasks corresponding to these specific objectives. The first task involved a thorough literature review and a selection of IHX candidates with different surface geometries as well as a summary of prototypic operational conditions. The second task involved optimization of PCHE design with numerical analyses of thermal-hydraulic performances and mechanical integrity. The subsequent task dealt with the development of testing facilities and engineering design of PCHE to be tested in s-CO 2 fluid conditions. The next task involved experimental investigation and validation of the thermal-hydraulic performances and thermal stress distribution of prototype PCHEs manufactured with particular surface geometries. The last task involved an investigation of diffusion bonding process and posttest destructive testing to validate mechanical design methods adopted in the design process. The experimental work utilized the two test facilities at The Ohio State University (OSU) including one existing High-Temperature Helium Test Facility (HTHF) and the newly developed s-CO 2 test loop (STL) facility and s-CO 2 test facility at University of Wisconsin – Madison (UW).« less

Linguistic attention control: attention shifting governed by grammaticized elements of language.

PubMed

Taube-Schiff, Marlene; Segalowitz, Norman

2005-05-01

In 2 experiments, the authors investigated attention control for tasks involving the processing of grammaticized linguistic stimuli (function words) contextualized in sentence fragments. Attention control was operationalized as shift costs obtained with adult speakers of English in an alternating-runs experimental design (R. D. Rogers & S. Monsell, 1995). Experiment 1 yielded significant attention shift costs between tasks involving judgments about the meanings of grammatical function words. The authors used a 3-stage experimental design (G. Wylie & A. Allport, 2000), and the emerging pattern of results implicated task set reconfiguration and not task set inertia in these shift costs. Experiment 2 further demonstrated that shift costs were lower when the tasks involved shared attentional resources (processing the same grammatical dimension) versus unshared resources (different grammatical dimensions). The authors discuss the results from a cognitive linguistic perspective and for their implications for the view that language itself can serve a special attention-directing function.

Measuring and Advancing Experimental Design Ability in an Introductory Course without Altering Existing Lab Curriculum†

PubMed Central

Shanks, Ryan A.; Robertson, Chuck L.; Haygood, Christian S.; Herdliksa, Anna M.; Herdliska, Heather R.; Lloyd, Steven A.

2017-01-01

Introductory biology courses provide an important opportunity to prepare students for future courses, yet existing cookbook labs, although important in their own way, fail to provide many of the advantages of semester-long research experiences. Engaging, authentic research experiences aid biology students in meeting many learning goals. Therefore, overlaying a research experience onto the existing lab structure allows faculty to overcome barriers involving curricular change. Here we propose a working model for this overlay design in an introductory biology course and detail a means to conduct this lab with minimal increases in student and faculty workloads. Furthermore, we conducted exploratory factor analysis of the Experimental Design Ability Test (EDAT) and uncovered two latent factors which provide valid means to assess this overlay model’s ability to increase advanced experimental design abilities. In a pre-test/post-test design, we demonstrate significant increases in both basic and advanced experimental design abilities in an experimental and comparison group. We measured significantly higher gains in advanced experimental design understanding in students in the experimental group. We believe this overlay model and EDAT factor analysis contribute a novel means to conduct and assess the effectiveness of authentic research experiences in an introductory course without major changes to the course curriculum and with minimal increases in faculty and student workloads. PMID:28904647

Evaluation Designs for Practitioners. TM Report No. 35.

ERIC Educational Resources Information Center

Eash, Maurice J.; And Others

Practitioners are not afforded the luxury of ideal laboratory conditions. The natural settings of the classroom, the school, or the school system place constraints on the type of data obtainable; hence, educators must work with less than an ideal experimental design. Four evaluation designs used in natural settings are described. Each involves an…

Group-Based Life Design Counseling in an Italian Context

ERIC Educational Resources Information Center

Di Fabio, Annamaria; Maree, Jacobus Gideon

2012-01-01

This study examined the effectiveness of group-based Life Design Counseling using the Career-Story Interview. Written exercises were used to implement the seven topics in the Career-Story Interview. The present study employed an experimental design that involved two groups of Italian entrepreneurs from the agricultural and trade sectors, namely an…

Three-dimensional broadband omnidirectional acoustic ground cloak

NASA Astrophysics Data System (ADS)

Zigoneanu, Lucian; Popa, Bogdan-Ioan; Cummer, Steven A.

2014-04-01

The control of sound propagation and reflection has always been the goal of engineers involved in the design of acoustic systems. A recent design approach based on coordinate transformations, which is applicable to many physical systems, together with the development of a new class of engineered materials called metamaterials, has opened the road to the unconstrained control of sound. However, the ideal material parameters prescribed by this methodology are complex and challenging to obtain experimentally, even using metamaterial design approaches. Not surprisingly, experimental demonstration of devices obtained using transformation acoustics is difficult, and has been implemented only in two-dimensional configurations. Here, we demonstrate the design and experimental characterization of an almost perfect three-dimensional, broadband, and, most importantly, omnidirectional acoustic device that renders a region of space three wavelengths in diameter invisible to sound.

Experiential Learning Theory as a Guide for Effective Teaching.

ERIC Educational Resources Information Center

Murrell, Patricia H.; Claxton, Charles S.

1987-01-01

David Kolb's experiential learning theory involves a framework useful in designing courses that meet needs of diverse learners. Course designs providing systematic activities in concrete experience, reflective observations, abstract conceptualization, and active experimentation will be sensitive to students' learning styles while challenging…

An Example of Process Evaluation.

ERIC Educational Resources Information Center

Karl, Marion C.

The inappropriateness of standard experimental research design, which can stifle innovations, is discussed in connection with the problems of designing practical techniques for evaluating a Title III curriculum development project. The project, involving 12 school districts and 2,500 students, teaches concept understanding, critical thinking, and…

Learning with Concept and Knowledge Maps: A Meta-Analysis

ERIC Educational Resources Information Center

Nesbit, John C.; Adesope, Olusola O.

2006-01-01

This meta-analysis reviews experimental and quasi-experimental studies in which students learned by constructing, modifying, or viewing node-link diagrams. Following an exhaustive search for studies meeting specified design criteria, 67 standardized mean difference effect sizes were extracted from 55 studies involving 5,818 participants. Students…

Eliciting Reciprocal Peer-Tutoring Groups' Metacognitive Regulation through Structuring and Problematizing Scaffolds

ERIC Educational Resources Information Center

De Backer, Liesje; Van Keer, Hilde; Valcke, Martin

2016-01-01

The study examines whether structuring (SS) versus problematising scaffolds (PS) differently affect reciprocal peer-tutoring (RPT) groups' adoption of particular regulation skills, deep-level regulation, and tutee-initiated regulation. A quasi-experimental design involving two experimental groups (SS versus PS condition) was adopted. The first,…

75 FR 70753 - Market Test Involving Greeting Cards

Federal Register 2010, 2011, 2012, 2013, 2014

2010-11-18

... businesses will produce and distribute pre-approved envelopes according to specific design requirements which... will produce and distribute pre-approved envelopes with specific design requirements that will be... a market test beginning on or about January 1, 2011, of an experimental market dominant product...

Improving Students' Conceptual Understanding of a Specific Content Learning: A Designed Teaching Sequence

ERIC Educational Resources Information Center

Ahmad, N. J.; Lah, Y. Che

2012-01-01

The efficacy of a teaching sequence designed for a specific content of learning of electrochemistry is described in this paper. The design of the teaching draws upon theoretical insights into perspectives on learning and empirical studies to improve the teaching of this topic. A case study involving two classes, the experimental and baseline…

Students' Reactions to Manual-Based Treatments for Substance Abuse: An Exploratory Study

ERIC Educational Resources Information Center

Simons, Lori; Jacobucci, Raymond; Houston, Hank

2006-01-01

A quasi-experimental research design with quantitative and qualitative methodologies was conducted to explore reactions of 21 students to treatment manuals for substance abuse. Students were randomized to experimental (n = 11) and attention-control (n = 10) groups involving exposure to one of two manual-based therapy interventions. Quantitative…

Strategies Training in the Teaching of Reading Comprehension for EFL Learners in Indonesia

ERIC Educational Resources Information Center

Mistar, Junaidi; Zuhairi, Alfan; Yanti, Nofita

2016-01-01

This study investigated the effect of reading strategies training on the students' literal and inferential reading comprehension. The training involved three concrete strategies: predicting, text mapping, and summarizing. To achieve the purpose of this study, a quasi experimental design was selected with the experimental group being given reading…

Design and Diagnosis Problem Solving with Multifunctional Technical Knowledge Bases

DTIC Science & Technology

1992-09-29

STRUCTURE METHODOLOGY Design problem solving is a complex activity involving a number of subtasks. and a number of alternative methods potentially available...Conference on Artificial Intelligence. London: The British Computer Society, pp. 621-633. Friedland, P. (1979). Knowledge-based experimental design ...Computing Milieuxl: Management of Computing and Information Systems- -ty,*m man- agement General Terms: Design . Methodology Additional Key Words and Phrases

Compendium of Authenticated Systems and Logistics Terms, Definitions and Acronyms

DTIC Science & Technology

1981-04-01

assigned for storage operations, within OTHER NON WAREHOUSE SPACE a structure designed for other than storage Space being used for storage within any...opposed to Any work done in order to correct rejected work. administrative), design (engineering design and (AFLCM1 74-2) drafting), experimental test...study. (principal or designated representative) authorized practices, methodology , or procedures involved in to request, receive, store, and account

Cross-National Analysis of Islamic Fundamentalism

DTIC Science & Technology

2016-01-20

attitudes, and was fully involved in activities concerning questionnaire design including a new experimental design in the survey, pilot testing, and...possible collaboration with the research design of the panel survey in Tunisia. • Data analysis: Analyses of religious fundamentalism, women’s dress, trust...the Event History Calendar and the best methods to ask about knowledge and experience of past events. The group designed a series of cognitive

Design of a factorial experiment with randomization restrictions to assess medical device performance on vascular tissue.

PubMed

Diestelkamp, Wiebke S; Krane, Carissa M; Pinnell, Margaret F

2011-05-20

Energy-based surgical scalpels are designed to efficiently transect and seal blood vessels using thermal energy to promote protein denaturation and coagulation. Assessment and design improvement of ultrasonic scalpel performance relies on both in vivo and ex vivo testing. The objective of this work was to design and implement a robust, experimental test matrix with randomization restrictions and predictive statistical power, which allowed for identification of those experimental variables that may affect the quality of the seal obtained ex vivo. The design of the experiment included three factors: temperature (two levels); the type of solution used to perfuse the artery during transection (three types); and artery type (two types) resulting in a total of twelve possible treatment combinations. Burst pressures of porcine carotid and renal arteries sealed ex vivo were assigned as the response variable. The experimental test matrix was designed and carried out as a split-plot experiment in order to assess the contributions of several variables and their interactions while accounting for randomization restrictions present in the experimental setup. The statistical software package SAS was utilized and PROC MIXED was used to account for the randomization restrictions in the split-plot design. The combination of temperature, solution, and vessel type had a statistically significant impact on seal quality. The design and implementation of a split-plot experimental test-matrix provided a mechanism for addressing the existing technical randomization restrictions of ex vivo ultrasonic scalpel performance testing, while preserving the ability to examine the potential effects of independent factors or variables. This method for generating the experimental design and the statistical analyses of the resulting data are adaptable to a wide variety of experimental problems involving large-scale tissue-based studies of medical or experimental device efficacy and performance.

Design, Construction and Testing of Annular Diffusers for High Speed Civil Transportation Combustor Applications

NASA Technical Reports Server (NTRS)

Okhio, Cyril B.

1996-01-01

A theoretical and an experimental design study of subsonic flow through curved-wall annular diffusers has been initiated under this award in order to establish the most pertinent design parameters and hence performance characteristics for such devices, an the implications of their application in the design of engine components in the aerospace industries. The diffusers under this study are expected to contain appreciable regions of stall and the effects of swirl on their performance are being studied. The experimental work involves the application of Computer Aided Design software tool to the development of a suitable annular diffuse geometry and the subsequent downloading of such data to a CNC machine at Central State University (CSU). Two experimental run segments have been completed so far during FY-95 involving flow visualization and diffuser performance evaluation based on Kinetic Energy Dissipation. The method of calculation of the performance of diffusers based on pressure recovery coefficient has been shown to have some shortcomings and so the kinetic energy dissipation approach has been introduced in the run segment two with some success. The application of the discretized, full Navier Stokes and Continuity equations to the numerical study of the problem described above for the time-mean flow is expected to follow. Various models of turbulence are being evaluated for adoption throughout the study and comparisons would be made with experimental data where they exist. Assessment of diffuser performance based on the dissipated mechanical energy would also be made. The result of the investigations are expected to indicate that more cost effective component design of such devices as diffusers which normally contain complex flows can still be achieved.

Concept Verification Test - Evaluation of Spacelab/Payload operation concepts

NASA Technical Reports Server (NTRS)

Mcbrayer, R. O.; Watters, H. H.

1977-01-01

The Concept Verification Test (CVT) procedure is used to study Spacelab operational concepts by conducting mission simulations in a General Purpose Laboratory (GPL) which represents a possible design of Spacelab. In conjunction with the laboratory a Mission Development Simulator, a Data Management System Simulator, a Spacelab Simulator, and Shuttle Interface Simulator have been designed. (The Spacelab Simulator is more functionally and physically representative of the Spacelab than the GPL.) Four simulations of Spacelab mission experimentation were performed, two involving several scientific disciplines, one involving life sciences, and the last involving material sciences. The purpose of the CVT project is to support the pre-design and development of payload carriers and payloads, and to coordinate hardware, software, and operational concepts of different developers and users.

Fundamental phenomena on fuel decomposition and boundary layer combustion processes with applications to hybrid rocket motors

NASA Technical Reports Server (NTRS)

Kuo, Kenneth K.; Lu, Y. C.; Chiaverini, Martin J.; Harting, George C.

1994-01-01

An experimental study on the fundamental processes involved in fuel decomposition and boundary layer combustion in hybrid rocket motors is being conducted at the High Pressure Combustion Laboratory of the Pennsylvania State University. This research should provide an engineering technology base for development of large scale hybrid rocket motors as well as a fundamental understanding of the complex processes involved in hybrid propulsion. A high pressure slab motor has been designed for conducting experimental investigations. Oxidizer (LOX or GOX) is injected through the head-end over a solid fuel (HTPB) surface. Experiments using fuels supplied by NASA designated industrial companies will also be conducted. The study focuses on the following areas: measurement and observation of solid fuel burning with LOX or GOX, correlation of solid fuel regression rate with operating conditions, measurement of flame temperature and radical species concentrations, determination of the solid fuel subsurface temperature profile, and utilization of experimental data for validation of a companion theoretical study also being conducted at PSU.

Evaluation of high temperature superconductive thermal bridges for space-borne cryogenic infrared detectors

NASA Technical Reports Server (NTRS)

Scott, Elaine P.

1993-01-01

The focus of this research is on the reduction of the refrigeration requirements for infrared sensors operating in space through the use of high temperature superconductive (HTS) materials as electronic leads between the cooled sensors and the relatively warmer data acquisition components. Specifically, this initial study was directed towards the design of an experiment to quantify the thermal performance of these materials in the space environment. First, an intensive review of relevant literature was undertaken, and then, design requirements were formulated. From this background information, a preliminary experimental design was developed. Additional studies will involve a thermal analysis of the experiment and further modifications of the experimental design.

Quasi-experimental evaluation without regression analysis.

PubMed

Rohrer, James E

2009-01-01

Evaluators of public health programs in field settings cannot always randomize subjects into experimental or control groups. By default, they may choose to employ the weakest study design available: the pretest, posttest approach without a comparison group. This essay argues that natural experiments involving comparison groups are within reach of public health program managers. Methods for analyzing natural experiments are discussed.

Developing the Concept of Perimeter and Area in Students with Learning Disabilities (LD)

ERIC Educational Resources Information Center

Kozulin, Alex; Kazaz, Sigalit

2017-01-01

The present research is aimed at developing an educational program effective for the development of the concepts of perimeter and area in students with LD and testing this program. The study combined action research with quasi-experimental design involving experimental (LD) and comparison (non-LD) groups. The intervention program consisted of 12…

Underwater Sediment Sampling Research

DTIC Science & Technology

2017-01-01

resolved through further experimentation . Underwater Sediment Sampling Research vi UNCLAS//Public | CG-926 RDC | A. Hanson, et al. Public...Chemical Oceanographer, and In situ Chemical Analysis Subject Matter Expert (SME). 2 LABORATORY TEST SET UP The experimental research and laboratory... methodology involved using a fluorescence oil sensor (Turner Designs Cyclops-7) to measure the TPH contained in the interstitial waters (i.e., pore

Comparative Assessment of Torso and Seat Mounted Restraint Systems using Manikins on the Vertical Deceleration Tower

DTIC Science & Technology

2017-03-01

experimental effort involving a series of +z-axis impact tests was conducted on the 711th Human Performance Wing’s Vertical Deceleration Tower (VDT...parameters) and a JSF-styled ejection seat configuration (combined non -baseline test parameters) produced similar biodynamic response parameters for the LOIS...Photography .............................................................................. 12 6.0 EXPERIMENTAL DESIGN

Visual Literacy and the Integration of Parametric Modeling in the Problem-Based Curriculum

ERIC Educational Resources Information Center

Assenmacher, Matthew Benedict

2013-01-01

This quasi-experimental study investigated the application of visual literacy skills in the form of parametric modeling software in relation to traditional forms of sketching. The study included two groups of high school technical design students. The control and experimental groups involved in the study consisted of two randomly selected groups…

Experimental Study of Middle-Term Training in Social Cognition in Preschoolers

ERIC Educational Resources Information Center

Houssa, Marine; Nader-Grosbois, Nathalie

2016-01-01

In an experimental design, we examined the effects of middle-term training in social information processing (SIP) and in Theory of Mind (ToM) on preschoolers' social cognition and social adjustment. 48 preschoolers took part in a pre-test and post-test session involving cognitive, socio-cognitive and social adjustment (direct and indirect)…

Using Different Types of Dictionaries for Improving EFL Reading Comprehension and Vocabulary Learning

ERIC Educational Resources Information Center

Alharbi, Majed A.

2016-01-01

This study investigated the effects of monolingual book dictionaries, popup dictionaries, and type-in dictionaries on improving reading comprehension and vocabulary learning in an EFL program. An experimental design involving four groups and a post-test was chosen for the experiment: (1) pop-up dictionary (experimental group 1); (2) type-in…

R. A. Fisher and his advocacy of randomization.

PubMed

Hall, Nancy S

2007-01-01

The requirement of randomization in experimental design was first stated by R. A. Fisher, statistician and geneticist, in 1925 in his book Statistical Methods for Research Workers. Earlier designs were systematic and involved the judgment of the experimenter; this led to possible bias and inaccurate interpretation of the data. Fisher's dictum was that randomization eliminates bias and permits a valid test of significance. Randomization in experimenting had been used by Charles Sanders Peirce in 1885 but the practice was not continued. Fisher developed his concepts of randomizing as he considered the mathematics of small samples, in discussions with "Student," William Sealy Gosset. Fisher published extensively. His principles of experimental design were spread worldwide by the many "voluntary workers" who came from other institutions to Rothamsted Agricultural Station in England to learn Fisher's methods.

Compiler-aided systematic construction of large-scale DNA strand displacement circuits using unpurified components

NASA Astrophysics Data System (ADS)

Thubagere, Anupama J.; Thachuk, Chris; Berleant, Joseph; Johnson, Robert F.; Ardelean, Diana A.; Cherry, Kevin M.; Qian, Lulu

2017-02-01

Biochemical circuits made of rationally designed DNA molecules are proofs of concept for embedding control within complex molecular environments. They hold promise for transforming the current technologies in chemistry, biology, medicine and material science by introducing programmable and responsive behaviour to diverse molecular systems. As the transformative power of a technology depends on its accessibility, two main challenges are an automated design process and simple experimental procedures. Here we demonstrate the use of circuit design software, combined with the use of unpurified strands and simplified experimental procedures, for creating a complex DNA strand displacement circuit that consists of 78 distinct species. We develop a systematic procedure for overcoming the challenges involved in using unpurified DNA strands. We also develop a model that takes synthesis errors into consideration and semi-quantitatively reproduces the experimental data. Our methods now enable even novice researchers to successfully design and construct complex DNA strand displacement circuits.

Structurally compliant rocket engine combustion chamber: Experimental and analytical validation

NASA Technical Reports Server (NTRS)

Jankovsky, Robert S.; Arya, Vinod K.; Kazaroff, John M.; Halford, Gary R.

1994-01-01

A new, structurally compliant rocket engine combustion chamber design has been validated through analysis and experiment. Subscale, tubular channel chambers have been cyclically tested and analytically evaluated. Cyclic lives were determined to have a potential for 1000 percent increase over those of rectangular channel designs, the current state of the art. Greater structural compliance in the circumferential direction gave rise to lower thermal strains during hot firing, resulting in lower thermal strain ratcheting and longer predicted fatigue lives. Thermal, structural, and durability analyses of the combustion chamber design, involving cyclic temperatures, strains, and low-cycle fatigue lives, have corroborated the experimental observations.

Experimental design matters for statistical analysis: how to handle blocking.

PubMed

Jensen, Signe M; Schaarschmidt, Frank; Onofri, Andrea; Ritz, Christian

2018-03-01

Nowadays, evaluation of the effects of pesticides often relies on experimental designs that involve multiple concentrations of the pesticide of interest or multiple pesticides at specific comparable concentrations and, possibly, secondary factors of interest. Unfortunately, the experimental design is often more or less neglected when analysing data. Two data examples were analysed using different modelling strategies. First, in a randomized complete block design, mean heights of maize treated with a herbicide and one of several adjuvants were compared. Second, translocation of an insecticide applied to maize as a seed treatment was evaluated using incomplete data from an unbalanced design with several layers of hierarchical sampling. Extensive simulations were carried out to further substantiate the effects of different modelling strategies. It was shown that results from suboptimal approaches (two-sample t-tests and ordinary ANOVA assuming independent observations) may be both quantitatively and qualitatively different from the results obtained using an appropriate linear mixed model. The simulations demonstrated that the different approaches may lead to differences in coverage percentages of confidence intervals and type 1 error rates, confirming that misleading conclusions can easily happen when an inappropriate statistical approach is chosen. To ensure that experimental data are summarized appropriately, avoiding misleading conclusions, the experimental design should duly be reflected in the choice of statistical approaches and models. We recommend that author guidelines should explicitly point out that authors need to indicate how the statistical analysis reflects the experimental design. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Measuring Thermal Variations in a Valley Environment Using a Team, Field Project Designed by Students

ERIC Educational Resources Information Center

Abbott, J. Anthony

2006-01-01

Students frequently struggle when scientific instruction seems divorced from personal experience, especially in the physical sub-disciplines, like climatology, where exercise books often present historical or abstracted case studies. In contrast I present a three-phase project involving student input on experimental design, data collection, and…

The Effects of a Course in Science and Culture Designed for Secondary School Students.

ERIC Educational Resources Information Center

Cossman, George Wilford

This study was designed to evaluate the success of an experimental secondary school course for fostering scientific literacy and the development of scientific attitudes. Students were matched using I.Q., sex, grade level, involvement with formal science courses, and cumulative grade point average. Twenty-one "self selected" eleventh and…

Schooling as a Knowledge System: Lessons from Cramim Experimental School

ERIC Educational Resources Information Center

Chen, David

2010-01-01

This article describes an experiment utilizing a research and development strategy to design and implement an innovative school for the future. The development of Cramim Elementary School was a joint effort of researchers from Tel-Aviv University and the staff of the school. The design stage involved constructing a new theoretical framework that…

Effects of mothers involved in dental health program for their children.

PubMed

Choi, Hye Seon; Ahn, Hye Young

2012-12-01

The purpose of this study was to identify the effects of mothers' involvement in a dental health program for their elementary school children. This study was a non-equivalent control group pre-post test design in which knowledge and behaviors related to dental health, perceived benefits and barriers, self-efficacy and plaque control scores were compared between the experimental group (n=26) for whom the dental health program included the direct involvement of the mothers, and the control group (n=24) for whom knowledge related to dental health was provided through brochures. Scores for the experimental group in which the mothers were involved in the dental health program were significantly higher for knowledge, behaviors in dental health, self-efficacy and plaque control compared to the control group. Results of this study suggest that mothers involvement in the dental health program is effective in reinforcing dental health enhancing behavior in elementary school children.

Influence of Cultural, Organizational, and Automation Capability on Human Automation Trust: A Case Study of Auto-GCAS Experimental Test Pilots

NASA Technical Reports Server (NTRS)

Koltai, Kolina; Ho, Nhut; Masequesmay, Gina; Niedober, David; Skoog, Mark; Cacanindin, Artemio; Johnson, Walter; Lyons, Joseph

2014-01-01

This paper discusses a case study that examined the influence of cultural, organizational and automation capability upon human trust in, and reliance on, automation. In particular, this paper focuses on the design and application of an extended case study methodology, and on the foundational lessons revealed by it. Experimental test pilots involved in the research and development of the US Air Force's newly developed Automatic Ground Collision Avoidance System served as the context for this examination. An eclectic, multi-pronged approach was designed to conduct this case study, and proved effective in addressing the challenges associated with the case's politically sensitive and military environment. Key results indicate that the system design was in alignment with pilot culture and organizational mission, indicating the potential for appropriate trust development in operational pilots. These include the low-vulnerability/ high risk nature of the pilot profession, automation transparency and suspicion, system reputation, and the setup of and communications among organizations involved in the system development.

Exploring the Impact of Professional Development and Professional Practice on School Leaders' Self-Efficacy: A Quasi-Experimental Study

ERIC Educational Resources Information Center

Petridou, Alexandra; Nicolaidou, Maria; Karagiorgi, Yiasemina

2017-01-01

Self-efficacy is extensively discussed within social cognitive theory. This study aimed to explore the impact of professional development and practice on school leaders' self-efficacy in Cyprus. A quasi-experimental design involving 2 groups of novice secondary deputy head teachers was employed. All participants practised leadership at the time,…

Applications of Advanced Experimental Methodologies to AWAVS Training Research. Final Report, May 1977-July 1978.

ERIC Educational Resources Information Center

Simon, Charles W.

A major part of the Naval Training Equipment Center's Aviation Wide Angle Visual System (AWAVS) program involves behavioral research to provide a basis for establishing design criteria for flight trainers. As part of the task of defining the purpose and approach of this program, the applications of advanced experimental methods are explained and…

For the Love of Statistics: Appreciating and Learning to Apply Experimental Analysis and Statistics through Computer Programming Activities

ERIC Educational Resources Information Center

Mascaró, Maite; Sacristán, Ana Isabel; Rufino, Marta M.

2016-01-01

For the past 4 years, we have been involved in a project that aims to enhance the teaching and learning of experimental analysis and statistics, of environmental and biological sciences students, through computational programming activities (using R code). In this project, through an iterative design, we have developed sequences of R-code-based…

An experimental approach to free vibration analysis of smart composite beam

NASA Astrophysics Data System (ADS)

Yashavantha Kumar, G. A.; Sathish Kumar, K. M.

2018-02-01

Experimental vibration analysis is a main concern of this study. In designing any structural component the important parameter that has to be considered is vibration. The present work involves the experimental investigation of free vibration analysis of a smart beam. Smart beam consists of glass/epoxy composite as a main substrate and two PZT patches. The PZT patches are glued above and below the main beam. By experimentation the natural frequencies and mode shapes are obtained for both with and without PZT patches of a beam. Finally through experimentation the response of the smart beam is recorded.

Fundamental phenomena on fuel decomposition and boundary layer combustion processes with applications to hybrid rocket motors

NASA Technical Reports Server (NTRS)

Kuo, Kenneth K.; Lu, Y. C.; Chiaverini, Martin J.; Harting, George C.

1994-01-01

An experimental study on the fundamental processes involved in fuel decomposition and boundary layer combustion in hybrid rocket motors is being conducted at the High Pressure Combustion Laboratory of the Pennsylvania State University. This research should provide a useful engineering technology base in the development of hybrid rocket motors as well as a fundamental understanding of the complex processes involved in hybrid propulsion. A high pressure slab motor has been designed and manufactured for conducting experimental investigations. Oxidizer (LOX or GOX) supply and control systems have been designed and partly constructed for the head-end injection into the test chamber. Experiments using HTPB fuel, as well as fuels supplied by NASA designated industrial companies will be conducted. Design and construction of fuel casting molds and sample holders have been completed. The portion of these items for industrial company fuel casting will be sent to the McDonnell Douglas Aerospace Corporation in the near future. The study focuses on the following areas: observation of solid fuel burning processes with LOX or GOX, measurement and correlation of solid fuel regression rate with operating conditions, measurement of flame temperature and radical species concentrations, determination of the solid fuel subsurface temperature profile, and utilization of experimental data for validation of a companion theoretical study (Part 2) also being conducted at PSU.

Design of a factorial experiment with randomization restrictions to assess medical device performance on vascular tissue

PubMed Central

2011-01-01

Background Energy-based surgical scalpels are designed to efficiently transect and seal blood vessels using thermal energy to promote protein denaturation and coagulation. Assessment and design improvement of ultrasonic scalpel performance relies on both in vivo and ex vivo testing. The objective of this work was to design and implement a robust, experimental test matrix with randomization restrictions and predictive statistical power, which allowed for identification of those experimental variables that may affect the quality of the seal obtained ex vivo. Methods The design of the experiment included three factors: temperature (two levels); the type of solution used to perfuse the artery during transection (three types); and artery type (two types) resulting in a total of twelve possible treatment combinations. Burst pressures of porcine carotid and renal arteries sealed ex vivo were assigned as the response variable. Results The experimental test matrix was designed and carried out as a split-plot experiment in order to assess the contributions of several variables and their interactions while accounting for randomization restrictions present in the experimental setup. The statistical software package SAS was utilized and PROC MIXED was used to account for the randomization restrictions in the split-plot design. The combination of temperature, solution, and vessel type had a statistically significant impact on seal quality. Conclusions The design and implementation of a split-plot experimental test-matrix provided a mechanism for addressing the existing technical randomization restrictions of ex vivo ultrasonic scalpel performance testing, while preserving the ability to examine the potential effects of independent factors or variables. This method for generating the experimental design and the statistical analyses of the resulting data are adaptable to a wide variety of experimental problems involving large-scale tissue-based studies of medical or experimental device efficacy and performance. PMID:21599963

Seven Experiment Designs Addressing Problems of Safety and Capacity on Two-Lane Rural Highways : Volume 6. Experimental Design for Comparative Evaluation of Warning-Advisory and Regulatory Traffic Control Devices

DOT National Transportation Integrated Search

2006-04-14

This report presents the results of the national evaluation of the South Lake Tahoe coordinated Transit System (CTS) Project. The CTS Project involved combining transit services offered by private and public sector stakeholders in South Lake Tahoe in...

The Effect of Environmental Science Projects on Students' Environmental Knowledge and Science Attitudes

ERIC Educational Resources Information Center

Al-Balushi, Sulaiman M.; Al-Aamri, Shamsa S.

2014-01-01

The current study explores the effectiveness of involving students in environmental science projects for their environmental knowledge and attitudes towards science. The study design is a quasi-experimental pre-post control group design. The sample was 62 11th-grade female students studying at a public school in Oman. The sample was divided into…

A RANDOM-SCAN DISPLAY OF PREDICTED SATELLITE POSITIONS.

DTIC Science & Technology

With the completion of the NRL evaluation of the experimental model of the Satellite Position Prediction and Display equipment ( SPAD ), efforts were...directed toward the design of an operational version of SPAD . Possible design and equipment configurations were proposed which would lead to a...substantial savings in cost and reduced equipment complexity. These designs involve the displaying of the SPAD information by means of a random scanning of

Intergration of system identification and robust controller designs for flexible structures in space

NASA Technical Reports Server (NTRS)

Juang, Jer-Nan; Lew, Jiann-Shiun

1990-01-01

An approach is developed using experimental data to identify a reduced-order model and its model error for a robust controller design. There are three steps involved in the approach. First, an approximately balanced model is identified using the Eigensystem Realization Algorithm, which is an identification algorithm. Second, the model error is calculated and described in frequency domain in terms of the H(infinity) norm. Third, a pole placement technique in combination with a H(infinity) control method is applied to design a controller for the considered system. A set experimental data from an existing setup, namely the Mini-Mast system, is used to illustrate and verify the approach.

The Influence of Computer-Assisted Instruction on Students' Conceptual Understanding of Chemical Bonding and Attitude toward Chemistry: A Case for Turkey

ERIC Educational Resources Information Center

Ozmen, Haluk

2008-01-01

In this study, the effect of computer-assisted instruction on conceptual understanding of chemical bonding and attitude toward chemistry was investigated. The study employed a quasi-experimental design involving 11 grade students; 25 in an experimental and 25 in a control group. The Chemical Bonding Achievement Test (CBAT) consisting of 15…

A Short Dance-Exercise Intervention as a Strategy for Improving Quality of Life in Inactive Workers

ERIC Educational Resources Information Center

Barranco-Ruiz, Yaira; Mandic, Sandra; Paz-Viteri, Susana; Guerendiain, Marcela; Sandoval, FaustoVinicio; Villa-González, Emilio

2017-01-01

Objective: To investigate the effects of a short exercise intervention based on the use of a Zumba Fitness® programme on the quality of life (QoL) in inactive adult workers. Design: Non-experimental pre-test/post-test study involving one experimental group of inactive university workers. Setting: Riobamba in the Andean region of central Ecuador.…

Digital Storytelling for Enhancing Student Academic Achievement, Critical Thinking, and Learning Motivation: A Year-Long Experimental Study

ERIC Educational Resources Information Center

Yang, Ya-Ting C.; Wu, Wan-Chi I.

2012-01-01

The purpose of this study was to explore the impact of Digital storytelling (DST) on the academic achievement, critical thinking, and learning motivation of senior high school students learning English as a foreign language. The one-year study adopted a pretest and posttest quasi-experimental design involving 110 10th grade students in two English…

Experimental demonstration of photon upconversion via cooperative energy pooling

DOE PAGES

Weingarten, Daniel H.; LaCount, Michael D.; van de Lagemaat, Jao; ...

2017-03-15

Photon upconversion is a fundamental interaction of light and matter that has applications in fields ranging from bioimaging to microfabrication. However, all photon upconversion methods demonstrated thus far involve challenging aspects, including requirements of high excitation intensities, degradation in ambient air, requirements of exotic materials or phases, or involvement of inherent energy loss processes. Here we experimentally demonstrate a mechanism of photon upconversion in a thin film, binary mixture of organic chromophores that provides a pathway to overcoming the aforementioned disadvantages. This singlet-based process, called Cooperative Energy Pooling (CEP), utilizes a sensitizer-acceptor design in which multiple photoexcited sensitizers resonantly andmore » simultaneously transfer their energies to a higher-energy state on a single acceptor. Data from this proof-of-concept implementation is fit by a proposed model of the CEP process. As a result, design guidelines are presented to facilitate further research and development of more optimized CEP systems.« less

Experimental demonstration of photon upconversion via cooperative energy pooling

PubMed Central

Weingarten, Daniel H.; LaCount, Michael D.; van de Lagemaat, Jao; Rumbles, Garry; Lusk, Mark T.; Shaheen, Sean E.

2017-01-01

Photon upconversion is a fundamental interaction of light and matter that has applications in fields ranging from bioimaging to microfabrication. However, all photon upconversion methods demonstrated thus far involve challenging aspects, including requirements of high excitation intensities, degradation in ambient air, requirements of exotic materials or phases, or involvement of inherent energy loss processes. Here we experimentally demonstrate a mechanism of photon upconversion in a thin film, binary mixture of organic chromophores that provides a pathway to overcoming the aforementioned disadvantages. This singlet-based process, called Cooperative Energy Pooling (CEP), utilizes a sensitizer-acceptor design in which multiple photoexcited sensitizers resonantly and simultaneously transfer their energies to a higher-energy state on a single acceptor. Data from this proof-of-concept implementation is fit by a proposed model of the CEP process. Design guidelines are presented to facilitate further research and development of more optimized CEP systems. PMID:28294129

Experimental demonstration of photon upconversion via cooperative energy pooling

NASA Astrophysics Data System (ADS)

Weingarten, Daniel H.; Lacount, Michael D.; van de Lagemaat, Jao; Rumbles, Garry; Lusk, Mark T.; Shaheen, Sean E.

2017-03-01

Photon upconversion is a fundamental interaction of light and matter that has applications in fields ranging from bioimaging to microfabrication. However, all photon upconversion methods demonstrated thus far involve challenging aspects, including requirements of high excitation intensities, degradation in ambient air, requirements of exotic materials or phases, or involvement of inherent energy loss processes. Here we experimentally demonstrate a mechanism of photon upconversion in a thin film, binary mixture of organic chromophores that provides a pathway to overcoming the aforementioned disadvantages. This singlet-based process, called Cooperative Energy Pooling (CEP), utilizes a sensitizer-acceptor design in which multiple photoexcited sensitizers resonantly and simultaneously transfer their energies to a higher-energy state on a single acceptor. Data from this proof-of-concept implementation is fit by a proposed model of the CEP process. Design guidelines are presented to facilitate further research and development of more optimized CEP systems.

From Structure to Function: A Comprehensive Compendium of Tools to Unveil Protein Domains and Understand Their Role in Cytokinesis.

PubMed

Rincon, Sergio A; Paoletti, Anne

2016-01-01

Unveiling the function of a novel protein is a challenging task that requires careful experimental design. Yeast cytokinesis is a conserved process that involves modular structural and regulatory proteins. For such proteins, an important step is to identify their domains and structural organization. Here we briefly discuss a collection of methods commonly used for sequence alignment and prediction of protein structure that represent powerful tools for the identification homologous domains and design of structure-function approaches to test experimentally the function of multi-domain proteins such as those implicated in yeast cytokinesis.

Engineering at SLAC: Designing and constructing experimental devices for the Stanford Synchrotron Radiation Lightsource - Final Paper

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

Djang, Austin

2015-08-22

Thanks to the versatility of the beam lines at SSRL, research there is varied and benefits multiple fields. Each experiment requires a particular set of experiment equipment, which in turns requires its own particular assembly. As such, new engineering challenges arise from each new experiment. My role as an engineering intern has been to help solve these challenges, by designing and assembling experimental devices. My first project was to design a heated sample holder, which will be used to investigate the effect of temperature on a sample's x-ray diffraction pattern. My second project was to help set up an imagingmore » test, which involved designing a cooled grating holder and assembling multiple positioning stages. My third project was designing a 3D-printed pencil holder for the SSRL workstations.« less

Critical Need for Family-Based, Quasi-Experimental Designs in Integrating Genetic and Social Science Research

PubMed Central

Lahey, Benjamin B.; Turkheimer, Eric; Lichtenstein, Paul

2013-01-01

Researchers have identified environmental risks that predict subsequent psychological and medical problems. Based on these correlational findings, researchers have developed and tested complex developmental models and have examined biological moderating factors (e.g., gene–environment interactions). In this context, we stress the critical need for researchers to use family-based, quasi-experimental designs when trying to integrate genetic and social science research involving environmental variables because these designs rigorously examine causal inferences by testing competing hypotheses. We argue that sibling comparison, offspring of twins or siblings, in vitro fertilization designs, and other genetically informed approaches play a unique role in bridging gaps between basic biological and social science research. We use studies on maternal smoking during pregnancy to exemplify these principles. PMID:23927516

Critical need for family-based, quasi-experimental designs in integrating genetic and social science research.

PubMed

D'Onofrio, Brian M; Lahey, Benjamin B; Turkheimer, Eric; Lichtenstein, Paul

2013-10-01

Researchers have identified environmental risks that predict subsequent psychological and medical problems. Based on these correlational findings, researchers have developed and tested complex developmental models and have examined biological moderating factors (e.g., gene-environment interactions). In this context, we stress the critical need for researchers to use family-based, quasi-experimental designs when trying to integrate genetic and social science research involving environmental variables because these designs rigorously examine causal inferences by testing competing hypotheses. We argue that sibling comparison, offspring of twins or siblings, in vitro fertilization designs, and other genetically informed approaches play a unique role in bridging gaps between basic biological and social science research. We use studies on maternal smoking during pregnancy to exemplify these principles.

Theoretical and experimental investigations of sensor location for optimal aeroelastic system state estimation

NASA Technical Reports Server (NTRS)

Liu, G.

1985-01-01

One of the major concerns in the design of an active control system is obtaining the information needed for effective feedback. This involves the combination of sensing and estimation. A sensor location index is defined as the weighted sum of the mean square estimation errors in which the sensor locations can be regarded as estimator design parameters. The design goal is to choose these locations to minimize the sensor location index. The choice of the number of sensors is a tradeoff between the estimation quality based upon the same performance index and the total costs of installing and maintaining extra sensors. An experimental study for choosing the sensor location was conducted on an aeroelastic system. The system modeling which includes the unsteady aerodynamics model developed by Stephen Rock was improved. Experimental results verify the trend of the theoretical predictions of the sensor location index for different sensor locations at various wind speeds.

Effects of the Wisconsin Reading Design Comprehension Program on Reading Achievement and Self-Concept of Sixth Grade Students.

ERIC Educational Resources Information Center

Negley, Sandra Anne

The main purpose of this study was to determine and describe the effects of the comprehension component of the criterion-referenced reading program, Wisconsin Design for Reading Skills Development (WDRSD), on reading achievement and self-concept of sixth-grade students. Parametric techniques were employed in a quasi-experimental study involving 44…

Introducing Experimental Design by Evaluating Efficacy of Herbal Remedies (Do Herbal Remedies Really Work?)

ERIC Educational Resources Information Center

Smith, Robert A.; Pontiggia, Laura; Waterman, Carrie; Lichtenwalner, Meghan

2010-01-01

This paper is based upon experiments developed as part of a Directed Research course designed to provide undergraduate biology students experience in the principles and processes of the scientific method used in biological research. The project involved the evaluation of herbal remedies used in many parts of the world in the treatment of diseases…

Liquid Chromatographic Determination of Nitroanilines: An Experiment for the Quantitative Analysis Laboratory.

ERIC Educational Resources Information Center

Cantwell, Frederick F.; Brown, David W.

1981-01-01

Describes a three-hour liquid chromatography experiment involving rapid separation of colored compounds in glass columns packed with a nonpolar absorbent. Includes apparatus design, sample preparation, experimental procedures, and advantages for this determination. (SK)

Using decoy effects to influence an online brand choice: the role of price-quality trade-offs.

PubMed

Hsu, Huei-Chen; Liu, Wen-Liang

2011-04-01

This research aims to investigate decoy effects on online brand choices. To assess the influence of decoys, we test decoy effects on three constructs-product involvement, judgment conditions, and decoy conditions-within an online experiment. A survey of 635 Internet users and a 2 × 2 × 3 ANOVA between-subjects experimental design is used to guide the research design and the systematic analysis procedure. A major finding of this study is that a standard decoy seems to have a significant effect on an advertised (target) brand for high-involvement products; from the survey, it is also apparent that competitors can also use inferior decoys to increase brand preference for low-involvement products.

Statistical process control in nursing research.

PubMed

Polit, Denise F; Chaboyer, Wendy

2012-02-01

In intervention studies in which randomization to groups is not possible, researchers typically use quasi-experimental designs. Time series designs are strong quasi-experimental designs but are seldom used, perhaps because of technical and analytic hurdles. Statistical process control (SPC) is an alternative analytic approach to testing hypotheses about intervention effects using data collected over time. SPC, like traditional statistical methods, is a tool for understanding variation and involves the construction of control charts that distinguish between normal, random fluctuations (common cause variation), and statistically significant special cause variation that can result from an innovation. The purpose of this article is to provide an overview of SPC and to illustrate its use in a study of a nursing practice improvement intervention. Copyright © 2011 Wiley Periodicals, Inc.

Urban pedestrian accident countermeasures experimental evaluation. Volume 2, Accident studies

DOT National Transportation Integrated Search

1975-02-01

A pedestrian accident data collection system was established in six major cities. The system involved using the regular police accident report form and a specifically designed supplementary data form. The information on the forms was combined, and th...

Virtual parameter-estimation experiments in Bioprocess-Engineering education.

PubMed

Sessink, Olivier D T; Beeftink, Hendrik H; Hartog, Rob J M; Tramper, Johannes

2006-05-01

Cell growth kinetics and reactor concepts constitute essential knowledge for Bioprocess-Engineering students. Traditional learning of these concepts is supported by lectures, tutorials, and practicals: ICT offers opportunities for improvement. A virtual-experiment environment was developed that supports both model-related and experimenting-related learning objectives. Students have to design experiments to estimate model parameters: they choose initial conditions and 'measure' output variables. The results contain experimental error, which is an important constraint for experimental design. Students learn from these results and use the new knowledge to re-design their experiment. Within a couple of hours, students design and run many experiments that would take weeks in reality. Usage was evaluated in two courses with questionnaires and in the final exam. The faculties involved in the two courses are convinced that the experiment environment supports essential learning objectives well.

Statistical issues in quality control of proteomic analyses: good experimental design and planning.

PubMed

Cairns, David A

2011-03-01

Quality control is becoming increasingly important in proteomic investigations as experiments become more multivariate and quantitative. Quality control applies to all stages of an investigation and statistics can play a key role. In this review, the role of statistical ideas in the design and planning of an investigation is described. This involves the design of unbiased experiments using key concepts from statistical experimental design, the understanding of the biological and analytical variation in a system using variance components analysis and the determination of a required sample size to perform a statistically powerful investigation. These concepts are described through simple examples and an example data set from a 2-D DIGE pilot experiment. Each of these concepts can prove useful in producing better and more reproducible data. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Random Measurement Error Does Not Bias the Treatment Effect Estimate in the Regression-Discontinuity Design. II. When an Interaction Effect Is Present.

ERIC Educational Resources Information Center

Trochim, William M. K.; And Others

1991-01-01

The regression-discontinuity design involving a treatment interaction effect (TIE), pretest-posttest functional form specification, and choice of point-of-estimation of the TIE are examined. Formulas for controlling the magnitude of TIE in simulations can be used for simulating the randomized experimental case where estimation is not at the…

Humane Science Projects: Suggestions for Biology Studies That Are Scientifically Educational and Ethically Non-Controversial.

ERIC Educational Resources Information Center

Balcombe, Jonathan P., Comp.

This paper lists 35 studies in biology which can be tailored to suit the full range of student age groups and are designed to involve most or all of the key elements of the scientific process (study design, data collection and presentation, and experimental manipulation). Examples of some studies are: (1) study the growth of molds on food items…

Experimental Design for Hanford Low-Activity Waste Glasses with High Waste Loading

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

Piepel, Gregory F.; Cooley, Scott K.; Vienna, John D.

This report discusses the development of an experimental design for the initial phase of the Hanford low-activity waste (LAW) enhanced glass study. This report is based on a manuscript written for an applied statistics journal. Appendices A, B, and E include additional information relevant to the LAW enhanced glass experimental design that is not included in the journal manuscript. The glass composition experimental region is defined by single-component constraints (SCCs), linear multiple-component constraints (MCCs), and a nonlinear MCC involving 15 LAW glass components. Traditional methods and software for designing constrained mixture experiments with SCCs and linear MCCs are not directlymore » applicable because of the nonlinear MCC. A modification of existing methodology to account for the nonlinear MCC was developed and is described in this report. One of the glass components, SO 3, has a solubility limit in glass that depends on the composition of the balance of the glass. A goal was to design the experiment so that SO 3 would not exceed its predicted solubility limit for any of the experimental glasses. The SO 3 solubility limit had previously been modeled by a partial quadratic mixture model expressed in the relative proportions of the 14 other components. The partial quadratic mixture model was used to construct a nonlinear MCC in terms of all 15 components. In addition, there were SCCs and linear MCCs. This report describes how a layered design was generated to (i) account for the SCCs, linear MCCs, and nonlinear MCC and (ii) meet the goals of the study. A layered design consists of points on an outer layer, and inner layer, and a center point. There were 18 outer-layer glasses chosen using optimal experimental design software to augment 147 existing glass compositions that were within the LAW glass composition experimental region. Then 13 inner-layer glasses were chosen with the software to augment the existing and outer-layer glasses. The experimental design was completed by a center-point glass, a Vitreous State Laboratory glass, and replicates of the center point and Vitreous State Laboratory glasses.« less

Application of experimental design in geothermal resources assessment of Ciwidey-Patuha, West Java, Indonesia

NASA Astrophysics Data System (ADS)

Ashat, Ali; Pratama, Heru Berian

2017-12-01

The successful Ciwidey-Patuha geothermal field size assessment required integration data analysis of all aspects to determined optimum capacity to be installed. Resources assessment involve significant uncertainty of subsurface information and multiple development scenarios from these field. Therefore, this paper applied the application of experimental design approach to the geothermal numerical simulation of Ciwidey-Patuha to generate probabilistic resource assessment result. This process assesses the impact of evaluated parameters affecting resources and interacting between these parameters. This methodology have been successfully estimated the maximum resources with polynomial function covering the entire range of possible values of important reservoir parameters.

An Experimental Fish Ethology Unit.

ERIC Educational Resources Information Center

Fisher, Ronald L., Jr.; Novak, John A.

1984-01-01

Describes a series of four experiments designed for small group involvement (each requiring 6 days) emphasizing students' scientific methodology. Topics include: feeding behavior; light/temperature effects on reproduction; effect of density on feeding; and altered male/female ratios on male behavior. Each experiment includes introduction, material…

A Classroom Demonstration of Psychrometrics.

ERIC Educational Resources Information Center

Clark, Jim A.; Nikolajczyk, David R.

1983-01-01

Presented is a bench-top demonstration of heating/humidification designed to provide visual confirmation of psychrometric principles outlined in thermodynamics texts. Includes a schematic sketch of the heater/humidifier apparatus, discussion of the six steps involved during the demonstration, and a table of experimental results. (JN)

MODELING A MIXTURE: PBPK/PD APPROACHES FOR PREDICTING CHEMICAL INTERACTIONS.

EPA Science Inventory

Since environmental chemical exposures generally involve multiple chemicals, there are both regulatory and scientific drivers to develop methods to predict outcomes of these exposures. Even using efficient statistical and experimental designs, it is not possible to test in vivo a...

Gravity sensing, a largely misunderstood trigger of plant orientated growth.

PubMed

Lopez, David; Tocquard, Kévin; Venisse, Jean-Stéphane; Legué, Valerie; Roeckel-Drevet, Patricia

2014-01-01

Gravity is a crucial environmental factor regulating plant growth and development. Plants have the ability to sense a change in the direction of gravity, which leads to the re-orientation of their growth direction, so-called gravitropism. In general, plant stems grow upward (negative gravitropism), whereas roots grow downward (positive gravitropism). Models describing the gravitropic response following the tilting of plants are presented and highlight that gravitropic curvature involves both gravisensing and mechanosensing, thus allowing to revisit experimental data. We also discuss the challenge to set up experimental designs for discriminating between gravisensing and mechanosensing. We then present the cellular events and the molecular actors known to be specifically involved in gravity sensing.

Identifying Effective Design Approaches to Allocate Genotypes in Two-Phase Designs: A Case Study in Pelargonium zonale.

PubMed

Molenaar, Heike; Boehm, Robert; Piepho, Hans-Peter

2017-01-01

Robust phenotypic data allow adequate statistical analysis and are crucial for any breeding purpose. Such data is obtained from experiments laid out to best control local variation. Additionally, experiments frequently involve two phases, each contributing environmental sources of variation. For example, in a former experiment we conducted to evaluate production related traits in Pelargonium zonale , there were two consecutive phases, each performed in a different greenhouse. Phase one involved the propagation of the breeding strains to obtain the stem cutting count, and phase two involved the assessment of root formation. The evaluation of the former study raised questions regarding options for improving the experimental layout: (i) Is there a disadvantage to using exactly the same design in both phases? (ii) Instead of generating a separate layout for each phase, can the design be optimized across both phases, such that the mean variance of a pair-wise treatment difference (MVD) can be decreased? To answer these questions, alternative approaches were explored to generate two-phase designs either in phase-wise order (Option 1) or across phases (Option 2). In Option 1 we considered the scenarios (i) using in both phases the same experimental design and (ii) randomizing each phase separately. In Option 2, we considered the scenarios (iii) generating a single design with eight replicates and splitting these among the two phases, (iv) separating the block structure across phases by dummy coding, and (v) design generation with optimal alignment of block units in the two phases. In both options, we considered the same or different block structures in each phase. The designs were evaluated by the MVD obtained by the intra-block analysis and the joint inter-block-intra-block analysis. The smallest MVD was most frequently obtained for designs generated across phases rather than for each phase separately, in particular when both phases of the design were separated with a single pseudo-level. The joint optimization ensured that treatment concurrences were equally balanced across pairs, one of the prerequisites for an efficient design. The proposed alternative approaches can be implemented with any model-based design packages with facilities to formulate linear models for treatment and block structures.

A brief understanding of process optimisation in microwave-assisted extraction of botanical materials: options and opportunities with chemometric tools.

PubMed

Das, Anup Kumar; Mandal, Vivekananda; Mandal, Subhash C

2014-01-01

Extraction forms the very basic step in research on natural products for drug discovery. A poorly optimised and planned extraction methodology can jeopardise the entire mission. To provide a vivid picture of different chemometric tools and planning for process optimisation and method development in extraction of botanical material, with emphasis on microwave-assisted extraction (MAE) of botanical material. A review of studies involving the application of chemometric tools in combination with MAE of botanical materials was undertaken in order to discover what the significant extraction factors were. Optimising a response by fine-tuning those factors, experimental design or statistical design of experiment (DoE), which is a core area of study in chemometrics, was then used for statistical analysis and interpretations. In this review a brief explanation of the different aspects and methodologies related to MAE of botanical materials that were subjected to experimental design, along with some general chemometric tools and the steps involved in the practice of MAE, are presented. A detailed study on various factors and responses involved in the optimisation is also presented. This article will assist in obtaining a better insight into the chemometric strategies of process optimisation and method development, which will in turn improve the decision-making process in selecting influential extraction parameters. Copyright © 2013 John Wiley & Sons, Ltd.

Visual monitoring of autonomous life sciences experimentation

NASA Technical Reports Server (NTRS)

Blank, G. E.; Martin, W. N.

1987-01-01

The design and implementation of a computerized visual monitoring system to aid in the monitoring and control of life sciences experiments on board a space station was investigated. A likely multiprocessor design was chosen, a plausible life science experiment with which to work was defined, the theoretical issues involved in the programming of a visual monitoring system for the experiment was considered on the multiprocessor, a system for monitoring the experiment was designed, and simulations of such a system was implemented on a network of Apollo workstations.

Modeling functional Magnetic Resonance Imaging (fMRI) experimental variables in the Ontology of Experimental Variables and Values (OoEVV)

PubMed Central

Burns, Gully A.P.C.; Turner, Jessica A.

2015-01-01

Neuroimaging data is raw material for cognitive neuroscience experiments, leading to scientific knowledge about human neurological and psychological disease, language, perception, attention and ultimately, cognition. The structure of the variables used in the experimental design defines the structure of the data gathered in the experiments; this in turn structures the interpretative assertions that may be presented as experimental conclusions. Representing these assertions and the experimental data which support them in a computable way means that they could be used in logical reasoning environments, i.e. for automated meta-analyses, or linking hypotheses and results across different levels of neuroscientific experiments. Therefore, a crucial first step in being able to represent neuroimaging results in a clear, computable way is to develop representations for the scientific variables involved in neuroimaging experiments. These representations should be expressive, computable, valid, extensible, and easy-to-use. They should also leverage existing semantic standards to interoperate easily with other systems. We present an ontology design pattern called the Ontology of Experimental Variables and Values (OoEVV). This is designed to provide a lightweight framework to capture mathematical properties of data, with appropriate ‘hooks’ to permit linkage to other ontology-driven projects (such as the Ontology of Biomedical Investigations, OBI). We instantiate the OoEVV system with a small number of functional Magnetic Resonance Imaging datasets, to demonstrate the system’s ability to describe the variables of a neuroimaging experiment. OoEVV is designed to be compatible with the XCEDE neuroimaging data standard for data collection terminology, and with the Cognitive Paradigm Ontology (CogPO) for specific reasoning elements of neuroimaging experimental designs. PMID:23684873

Experimental Investigation of the Interaction of Electrothermal Plasmas with Solid Propellants

DTIC Science & Technology

2007-09-14

formation increases propellant burning rate (Koleczko, et al . 2001). The experiments described here were designed to create time and spatially resolved...Pesce-Rodriguez 2004, Koleczko, et al . 2001). Most tests involving plasma propellant interactions involve higher plasma energies than the 3.1 kJ of...product that scatters light. The large jump in pressurization seen in closed bomb plasma ignition tests (Lieb, et al . 2001) during the plasma discharge

Design, construction and testing of annular diffusers for high speed civil transportation combustor applications

NASA Technical Reports Server (NTRS)

Okhio, Cyril B.

1995-01-01

A theoretical and an experimental design study of subsonic flow through curved-wall annular diffusers is being carried out in order to establish the most pertinent design parameters for such devices and the implications of their application in the design of engine components in the aerospace industries. This investigation consists of solving numerically the full Navier Stokes and Continuity equations for the time-mean flow. Various models of turbulence are being evaluated for adoption throughout the study and comparisons would be made with experimental data where they exist. Assessment of diffuser performance based on the dissipated mechanical energy would also be made. The experimental work involves the application of Computer Aided Design software tool to the development of a suitable annular diffuser geometry and the subsequent downloading of such data to a CNC machine at Central State University. The results of the investigations are expected to indicate that more cost effective component design of such devices as effective component design of such devices as diffusers which normally contain complex flows can still be achieved. In this regard a review paper was accepted and presented at the First International Conference on High Speed Civil Transportation Research held at North Carolina A&T in December of 1994.

Quantifying anti-gravity torques in the design of a powered exoskeleton.

PubMed

Ragonesi, Daniel; Agrawal, Sunil; Sample, Whitney; Rahman, Tariq

2011-01-01

Designing an upper extremity exoskeleton for people with arm weakness requires knowledge of the passive and active residual force capabilities of users. This paper experimentally measures the passive gravitational torques of 3 groups of subjects: able-bodied adults, able bodied children, and children with neurological disabilities. The experiment involves moving the arm to various positions in the sagittal plane and measuring the gravitational force at the wrist. This force is then converted to static gravitational torques at the elbow and shoulder. Data are compared between look-up table data based on anthropometry and empirical data. Results show that the look-up torques deviate from experimentally measured torques as the arm reaches up and down. This experiment informs designers of Upper Limb orthoses on the contribution of passive human joint torques.

Bayesian experimental design for models with intractable likelihoods.

PubMed

Drovandi, Christopher C; Pettitt, Anthony N

2013-12-01

In this paper we present a methodology for designing experiments for efficiently estimating the parameters of models with computationally intractable likelihoods. The approach combines a commonly used methodology for robust experimental design, based on Markov chain Monte Carlo sampling, with approximate Bayesian computation (ABC) to ensure that no likelihood evaluations are required. The utility function considered for precise parameter estimation is based upon the precision of the ABC posterior distribution, which we form efficiently via the ABC rejection algorithm based on pre-computed model simulations. Our focus is on stochastic models and, in particular, we investigate the methodology for Markov process models of epidemics and macroparasite population evolution. The macroparasite example involves a multivariate process and we assess the loss of information from not observing all variables. © 2013, The International Biometric Society.

Analysis of a Quasi-Experimental Design Based on Environmental Problem Solving for the Initial Training of Future Teachers of Environmental Education.

ERIC Educational Resources Information Center

Alvarez, Pedro; de la Fuente, Emilia I.; Perales, F. Javier; Garcia, Juan

2002-01-01

Presents research that incorporates constructivism with learning models in environmental education for the preparation and development of teachers. Involves (n=201) teacher trainees at the University of Granada in Spain. (YDS)

Old Wine into New Bottles.

ERIC Educational Resources Information Center

Crandall, G. Douglas

1997-01-01

Discusses how traditional lab exercises can be converted into investigative exercises. Describes an exercise on seed germination that has students design their own experiments based on their initial results. Involves students in the scientific process and allows them to experience the joys and disappointments of experimental work. (JRH)

Scaffolding for Argumentation in Hypothetical and Theoretical Biology Concepts

ERIC Educational Resources Information Center

Weng, Wan-Yun; Lin, Yu-Ren; She, Hsiao-Ching

2017-01-01

The present study investigated the effects of online argumentation scaffolding on students' argumentation involving hypothetical and theoretical biological concepts. Two types of scaffolding were developed in order to improve student argumentation: continuous scaffolding and withdraw scaffolding. A quasi-experimental design was used with four…

Introduction to Psychology.

ERIC Educational Resources Information Center

Edwards, Lesley

Designed for community students interested in learning about psychology as a field of study, this module offers group and individual activities to involve the beginning student in research, experimentation and discussion. Unit 1, "What Is Psychology?," includes the use of animals in psychology, ethics, the history of psychology, an…

Relationship of Leadership/Delegation to Group Effectiveness in Youth Organizations.

ERIC Educational Resources Information Center

Gamon, Julia A.; Carter, Richard I.

1987-01-01

Instructional materials designed to teach high school age youth how to increase member involvement by delegating leadership were experimentally tested. New materials made a difference in one test situation. Positive correlations were found between group effectiveness and tendency toward delegation. (Author/CH)

The Role of Proximity Effects in Transition-Edge Sensor Design and Performance

NASA Technical Reports Server (NTRS)

Smith, Stephen J.

2012-01-01

Transition-edge sensor (TES) microcalorimeters and bolometers are under development by numerous groups worldwide for a variety of applications involving the measurement of particle and photon radiation. Recent experimental and theoretical progress has led to the realization that the fundamental physics of some TES systems involves the longitudinal proximity effect between the electrical bias contacts and the TES. As such, these devices are described as SS'S (or SN'S) weak-links exhibiting Fraunhofer-like magnetic field dependence, and exponential temperature dependence, of the critical current. These discoveries, for the first time, provide a realistic theoretical framework for predicting the resistive transition as a function of temperature, current and magnetic field. In this contribution, we review the latest theoretical and experimental results and investigate how proximity effects play an important role in determining the resistive transition characteristics, which ultimately determines the dynamic range and energy resolution of TES detectors. We investigate how these effects could be utilized in device design to engineer desired transition characteristics for a given application.

Counteracting moment device for reduction of earthquake-induced excursions of multi-level buildings.

PubMed

Nagaya, K; Fukushima, T; Kosugi, Y

1999-05-01

A vibration-control mechanism for beams and columns was presented in our previous report in which the earthquake force was transformed into a vibration-control force by using a gear train mechanism. In our previous report, however, only the principle of transforming the earthquake force into the control force was presented; the discussion for real structures and the design method were not presented. The present article provides a theoretical analysis of the column which is used in multi-layered buildings. Experimental tests were carried out for a model of multi-layered buildings in the frequency range of a principal earthquake wave. Theoretical results are compared to the experimental data. The optimal design of the control mechanism, which is of importance in the column design, is presented. Numerical calculations are carried out for the optimal design. It is shown that vibrations of the column involving the mechanism are suppressed remarkably. The optimal design method and the analytical results are applicable to the design of the column.

Do cooperative learning and family involvement improve variables linked to academic performance?

PubMed

Santos Rego, Miguel A; Ferraces Otero, María J; Godas Otero, Agustín; Lorenzo Moledo, María M

2018-05-01

One of the most serious problems in the Spanish education system is the high percentage of school failure in Compulsory Secondary Education. The aim of this study is to analyze the influence of a socio-educational program based on cooperative learning and family involvement on a series of variables related to academic performance, paying particular attention to the differences between retained and non-retained students. A two-group quasi-experimental design incorporating pre-testing and post-testing was used. The study involved 146 students in the experimental group and 123 in the control group, 8 teachers, and 89 parents or other family members. The program was observed to have a positive effect on self-image, study habits, satisfaction with the subject, maternal support and control, and opinions about the school. In addition, the results for non-retained students are better. Cooperative work and family involvement in education affect the variables which research links to improving school performance.

Experimental and theoretical identification of a four- acoustic-inputs/two-vibration-outputs hearing system

NASA Astrophysics Data System (ADS)

Balaji, P. A.

1999-07-01

A cricket's ear is a directional acoustic sensor. It has a remarkable level of sensitivity to the direction of sound propagation in a narrow frequency bandwidth of 4-5 KHz. Because of its complexity, the directional sensitivity has long intrigued researchers. The cricket's ear is a four-acoustic-inputs/two-vibration-outputs system. In this dissertation, this system is examined in depth, both experimentally and theoretically, with a primary goal to understand the mechanics involved in directional hearing. Experimental identification of the system is done by using random signal processing techniques. Theoretical identification of the system is accomplished by analyzing sound transmission through complex trachea of the ear. Finally, a description of how the cricket achieves directional hearing sensitivity is proposed. The fundamental principle involved in directional heating of the cricket has been utilized to design a device to obtain a directional signal from non- directional inputs.

Assessment of an intervention to train teaching hospital care providers in quality management

PubMed Central

Francois, P; Vinck, D; Labarere, J; Reverdy, T; Peyrin, J

2005-01-01

Background: Successful implementation of continuous quality improvement (CQI) programs in hospitals remains rare in all countries, making it necessary to experiment with implementation methods while considering the cultural factors of resistance to change. Objective: To assess the impact of an educational intervention on involvement of clinical department staff in the quality process. Setting: Twelve voluntary clinical departments (six experimental and six controls) in a French 2000-bed university hospital comprising 40 clinical departments. Intervention: Three day training seminar to a group of 12–20 staff members from each department. Design: Quasi-experimental post-test only design study with control group conducted 12 months after the intervention with a questionnaire completed in a face-to-face interview. Subjects: 98 trained staff and 100 untrained staff from the six experimental departments and 100 staff from the six control departments. Principal measurements: Declared knowledge of the CQI methods and participation in quality management activities. Results: 286 people (96%) were involved in the study. More of the trained staff knew the CQI methods (62.4%) than staff in the control departments (16.5%) (adjusted odds ratio (ORa) = 10.6 (95% CI 4.97 to 22.62)). More trained staff also participated in quality improvement work groups than control department staff (76.3% v 14.0%; ORa = 27.4 (95% CI 11.6 to 64.4)). In the experimental departments the untrained staff's knowledge of CQI methods and their participation in work groups did not differ from that of control department staff. Conclusions: A continuing education intervention can involve care providers in CQI. Dissemination of knowledge from trained personnel to other staff members remains limited. PMID:16076785

An Evaluation of Five Critical/Creative Thinking Strategies for Secondary Science Students.

ERIC Educational Resources Information Center

Zielinski, Edward J.; Sarachine, D. Michael

1994-01-01

Critical and creative thinking lessons were designed and presented to 20 biology students in a rural high school. Student attitudes toward critical thinking activities improved significantly after activities involving experimentation, discrepant events, student questioning, ethical dilemmas, and divergent and critical thinking. Includes examples…

Investigations of Self-Pumped Phase Conjugate Laser Beams and Coherence Length

DTIC Science & Technology

1993-03-01

experiment was designed at the Naval Postgraduate School. This experimental arrangement involved a smaller argon-ion laser and a laser spectrometer...change in coherence length was observed in a phase conjugate laser beam. Eperimental results obtained in these experiments highlight the fact that

Global Design Optimization for Aerodynamics and Rocket Propulsion Components

NASA Technical Reports Server (NTRS)

Shyy, Wei; Papila, Nilay; Vaidyanathan, Rajkumar; Tucker, Kevin; Turner, James E. (Technical Monitor)

2000-01-01

Modern computational and experimental tools for aerodynamics and propulsion applications have matured to a stage where they can provide substantial insight into engineering processes involving fluid flows, and can be fruitfully utilized to help improve the design of practical devices. In particular, rapid and continuous development in aerospace engineering demands that new design concepts be regularly proposed to meet goals for increased performance, robustness and safety while concurrently decreasing cost. To date, the majority of the effort in design optimization of fluid dynamics has relied on gradient-based search algorithms. Global optimization methods can utilize the information collected from various sources and by different tools. These methods offer multi-criterion optimization, handle the existence of multiple design points and trade-offs via insight into the entire design space, can easily perform tasks in parallel, and are often effective in filtering the noise intrinsic to numerical and experimental data. However, a successful application of the global optimization method needs to address issues related to data requirements with an increase in the number of design variables, and methods for predicting the model performance. In this article, we review recent progress made in establishing suitable global optimization techniques employing neural network and polynomial-based response surface methodologies. Issues addressed include techniques for construction of the response surface, design of experiment techniques for supplying information in an economical manner, optimization procedures and multi-level techniques, and assessment of relative performance between polynomials and neural networks. Examples drawn from wing aerodynamics, turbulent diffuser flows, gas-gas injectors, and supersonic turbines are employed to help demonstrate the issues involved in an engineering design context. Both the usefulness of the existing knowledge to aid current design practices and the need for future research are identified.

Efficacy of Visual-Acoustic Biofeedback Intervention for Residual Rhotic Errors: A Single-Subject Randomization Study

ERIC Educational Resources Information Center

Byun, Tara McAllister

2017-01-01

Purpose: This study documented the efficacy of visual-acoustic biofeedback intervention for residual rhotic errors, relative to a comparison condition involving traditional articulatory treatment. All participants received both treatments in a single-subject experimental design featuring alternating treatments with blocked randomization of…

Sleep Does Not Enhance Motor Sequence Learning

ERIC Educational Resources Information Center

Rickard, Timothy C.; Cai, Denise J.; Rieth, Cory A.; Jones, Jason; Ard, M. Colin

2008-01-01

Improvements in motor sequence performance have been observed after a delay involving sleep. This finding has been taken as evidence for an active sleep consolidation process that enhances subsequent performance. In a review of this literature, however, the authors observed 4 aspects of data analyses and experimental design that could lead to…

An Application of Latent Variable Structural Equation Modeling for Experimental Research in Educational Technology

ERIC Educational Resources Information Center

Lee, Hyeon Woo

2011-01-01

As the technology-enriched learning environments and theoretical constructs involved in instructional design become more sophisticated and complex, a need arises for equally sophisticated analytic methods to research these environments, theories, and models. Thus, this paper illustrates a comprehensive approach for analyzing data arising from…

Energy: Machines, Science (Experimental): 5311.03.

ERIC Educational Resources Information Center

Castaldi, June P.

This unit of instruction was designed as an introductory course in energy involving six simple machines, electricity, magnetism, and motion. The booklet lists the relevant state-adopted texts and states the performance objectives for the unit. It provides an outline of the course content and suggests experiments, demonstrations, field trips, and…

Classroom Questioning with Immediate Electronic Response: Do Clickers Improve Learning?

ERIC Educational Resources Information Center

Yourstone, Steven A.; Kraye, Howard S.; Albaum, Gerald

2008-01-01

A number of studies have focused on how students and instructors feel about digital learning technologies. This research is focused on the substantive difference in learning outcomes between traditional classrooms and classrooms using clickers. A randomized block experimental design involving four sections of undergraduate Operations Management…

Conceptual Questions and Lack of Formal Reasoning: Are They Mutually Exclusive?

ERIC Educational Resources Information Center

Igaz, Csaba; Proksa, Miroslav

2012-01-01

Using specially designed conceptual question pairs, 9th grade students were tested on tasks (presented as experimental situations in pictorial form) that involved controlling the variables' scheme of formal reasoning. The question topics focused on these three chemical contexts: chemistry in everyday life, chemistry without formal concepts, and…

The Red and White Yeast Lab: An Introduction to Science as a Process.

ERIC Educational Resources Information Center

White, Brian T.

1999-01-01

Describes an experimental system based on an engineered strain of bakers' yeast that is designed to involve students in the process by which scientific knowledge is generated. Students are asked to determine why the yeast grow to form a reproducible pattern of red and white. (WRM)

An Open-Ended Investigative Microbial Ecology Laboratory for Introductory Biology

ERIC Educational Resources Information Center

Jones-Held, Susan; Paoletti, Robert; Glick, David; Held, Michael E.

2010-01-01

In this article we describe a multi-week investigative laboratory in microbial ecology/diversity and nitrogen cycling that we have used in our introductory biology course. This module encourages active student involvement in experimental design, using the scientific literature and quantitative analysis of large data sets. Students analyze soil…

Effects of Individual Development Accounts (IDAs) on Household Wealth and Saving Taste

ERIC Educational Resources Information Center

Huang, Jin

2010-01-01

This study examines effects of individual development accounts (IDAs) on household wealth of low-income participants. Methods: This study uses longitudinal survey data from the American Dream Demonstration (ADD) involving experimental design (treatment group = 537, control group = 566). Results: Results from quantile regression analysis indicate…

Attributing Responsibility for Child Maltreatment when Domestic Violence Is Present

ERIC Educational Resources Information Center

Landsman, Miriam J.; Hartley, Carolyn Copps

2007-01-01

Objective: The purpose of this study was to examine factors that influence how child welfare workers attribute responsibility for child maltreatment and child safety in cases involving domestic violence. Methods: The study used a factorial survey approach, combining elements of survey research with an experimental design. Case vignettes were…

A Study of the Generalizability of Teacher Change Quasi-Experiments

ERIC Educational Resources Information Center

Stringfield, Samuel; Schaffer, Eugene; Devlin-Scherer, Roberta

2017-01-01

Quasi-experimental teacher effectiveness studies have indicated that properly designed staff development programs can lead to changes in teacher and student behavior and to gains in student achievement. Those studies involved workshop series led by nationally known scholars. Using instructors from varied backgrounds, the current study examined the…

Linguistic Attention Control: Attention Shifting Governed by Grammaticized Elements of Language

ERIC Educational Resources Information Center

Taube-Schiff, Marlene; Segalowitz, Norman

2005-01-01

In 2 experiments, the authors investigated attention control for tasks involving the processing of grammaticized linguistic stimuli (function words) contextualized in sentence fragments. Attention control was operationalized as shift costs obtained with adult speakers of English in an alternating-runs experimental design (R. D. Rogers & S.…

Improving knowledge of garlic paste greening through the design of an experimental strategy.

PubMed

Aguilar, Miguel; Rincón, Francisco

2007-12-12

The furthering of scientific knowledge depends in part upon the reproducibility of experimental results. When experimental conditions are not set with sufficient precision, the resulting background noise often leads to poorly reproduced and even faulty experiments. An example of the catastrophic consequences of this background noise can be found in the design of strategies for the development of solutions aimed at preventing garlic paste greening, where reported results are contradictory. To avoid such consequences, this paper presents a two-step strategy based on the concept of experimental design. In the first step, the critical factors inherent to the problem are identified, using a 2(III)(7-4) Plackett-Burman experimental design, from a list of seven apparent critical factors (ACF); subsequently, the critical factors thus identified are considered as the factors to be optimized (FO), and optimization is performed using a Box and Wilson experimental design to identify the stationary point of the system. Optimal conditions for preventing garlic greening are examined after analysis of the complex process of green-pigment development, which involves both chemical and enzymatic reactions and is strongly influenced by pH, with an overall pH optimum of 4.5. The critical step in the greening process is the synthesis of thiosulfinates (allicin) from cysteine sulfoxides (alliin). Cysteine inhibits the greening process at this critical stage; no greening precursors are formed in the presence of around 1% cysteine. However, the optimal conditions for greening prevention are very sensitive both to the type of garlic and to manufacturing conditions. This suggests that optimal solutions for garlic greening prevention should be sought on a case-by-case basis, using the strategy presented here.

Application of the generalized reduced gradient method to conceptual aircraft design

NASA Technical Reports Server (NTRS)

Gabriele, G. A.

1984-01-01

The complete aircraft design process can be broken into three phases of increasing depth: conceptual design, preliminary design, and detail design. Conceptual design consists primarily of developing general arrangements and selecting the configuration that optimally satisfies all mission requirements. The result of the conceptual phase is a conceptual baseline configuration that serves as the starting point for the preliminary design phase. The conceptual design of an aircraft involves a complex trade-off of many independent variables that must be investigated before deciding upon the basic configuration. Some of these variables are discrete (number of engines), some represent different configurations (canard vs conventional tail) and some may represent incorporation of new technologies (aluminum vs composite materials). At Lockheed-Georgia, the sizing program is known as GASP (Generalized Aircraft Sizing Program). GASP is a large program containing analysis modules covering the many different disciplines involved fin defining the aricraft, such as aerodynamics, structures, stability and control, mission performance, and cost. These analysis modules provide first-level estimates the aircraft properties that are derived from handbook, experimental, and historical sources.

Microcosm assays and Taguchi experimental design for treatment of oil sludge containing high concentration of hydrocarbons.

PubMed

Castorena-Cortés, G; Roldán-Carrillo, T; Zapata-Peñasco, I; Reyes-Avila, J; Quej-Aké, L; Marín-Cruz, J; Olguín-Lora, P

2009-12-01

Microcosm assays and Taguchi experimental design was used to assess the biodegradation of an oil sludge produced by a gas processing unit. The study showed that the biodegradation of the sludge sample is feasible despite the high level of pollutants and complexity involved in the sludge. The physicochemical and microbiological characterization of the sludge revealed a high concentration of hydrocarbons (334,766+/-7001 mg kg(-1) dry matter, d.m.) containing a variety of compounds between 6 and 73 carbon atoms in their structure, whereas the concentration of Fe was 60,000 mg kg(-1) d.m. and 26,800 mg kg(-1) d.m. of sulfide. A Taguchi L(9) experimental design comprising 4 variables and 3 levels moisture, nitrogen source, surfactant concentration and oxidant agent was performed, proving that moisture and nitrogen source are the major variables that affect CO(2) production and total petroleum hydrocarbons (TPH) degradation. The best experimental treatment yielded a TPH removal of 56,092 mg kg(-1) d.m. The treatment was carried out under the following conditions: 70% moisture, no oxidant agent, 0.5% of surfactant and NH(4)Cl as nitrogen source.

Protein crystal growth in space

NASA Technical Reports Server (NTRS)

Bugg, C. E.; Clifford, D. W.

1987-01-01

The advantages of protein crystallization in space, and the applications of protein crystallography to drug design, protein engineering, and the design of synthetic vaccines are examined. The steps involved in using protein crystallography to determine the three-dimensional structure of a protein are discussed. The growth chamber design and the hand-held apparatus developed for protein crystal growth by vapor diffusion techniques (hanging-drop method) are described; the experimental data from the four Shuttle missions are utilized to develop hardware for protein crystal growth in space and to evaluate the effects of gravity on protein crystal growth.

Psychoeducational preparation of children for surgery: the importance of parental involvement.

PubMed

Li, Ho Cheung William; Lopez, Violeta; Lee, Tin Loi Isabel

2007-01-01

To examine the effects of therapeutic play intervention on outcomes of children undergoing day surgery, and to highlight the importance of parental involvement in the psychoeducational preparation of children for surgery. A randomized controlled trial, two group pre-test and repeated post-test, between subjects design was employed. Hong Kong Chinese children (7-12 years of age; n=203) admitted for elective surgery in a day surgery unit, along with their parents during a 13-month period, were invited to participate in the study. By using a simple complete randomization method, 97 of children with their parents were assigned to the experimental group receiving therapeutic play intervention, and 106 children with their parents were assigned to the control group receiving routine information preparation. The results showed that both children and their parents in the experimental group reported lower state anxiety scores in pre- and post-operative periods. Children in the experimental group exhibited fewer instances of negative emotional behaviors and parents in the experimental group reported greater satisfaction. The results, however, find no differences in children's post-operative pain between the two groups. The study provides empirical evidence to support the effectiveness of using therapeutic play intervention and the importance of parental involvement in the psychoeducational preparation of children for surgery. The findings heighten the awareness of the importance of integrating therapeutic play and parental involvement as essential components of holistic and quality nursing care to prepare children for surgery.

Impact of the ConRed program on different cyberbulling roles.

PubMed

Del Rey, Rosario; Casas, José A; Ortega, Rosario

2016-01-01

This article presents results from an evaluation of the ConRed cyberbullying intervention program. The program's impacts were separately determined for the different roles within cyberbullying that students can take, i.e., cyber-victims, cyber-bullies, cyber-bully/victims, and bystanders. The ConRed program is a theory-driven program designed to prevent cyberbullying and improve cyberbullying coping skills. It involves students, teachers, and families. During a 3-month period, external experts conducted eight training sessions with students, two with teachers and one with families. ConRed was evaluated through a quasi-experimental design, in which students from three secondary schools were separated into experimental and control groups. The sample comprised 875 students, aged between 11 and 19 years. More students (n = 586) were allocated to the experimental groups at the specific insistence of the management of all schools; the remainder (n = 289) formed the control. Repeated measures MANOVA showed that cyber victims, cyber aggressors and cyberbully/victims reduced their involvement in cyberbullying. Moreover, cyber-victims and bystanders adjusted their perceptions about their control of personal information on the Internet, and cyber aggressors and bystanders reduced their Internet dependence. The ConRed program had stronger effects on male participants, especially in heightening their affective empathy. © 2015 Wiley Periodicals, Inc.

Damage level prediction of non-reshaped berm breakwater using ANN, SVM and ANFIS models

NASA Astrophysics Data System (ADS)

Mandal, Sukomal; Rao, Subba; N., Harish; Lokesha

2012-06-01

The damage analysis of coastal structure is very important as it involves many design parameters to be considered for the better and safe design of structure. In the present study experimental data for non-reshaped berm breakwater are collected from Marine Structures Laboratory, Department of Applied Mechanics and Hydraulics, NITK, Surathkal, India. Soft computing techniques like Artificial Neural Network (ANN), Support Vector Machine (SVM) and Adaptive Neuro Fuzzy Inference system (ANFIS) models are constructed using experimental data sets to predict the damage level of non-reshaped berm breakwater. The experimental data are used to train ANN, SVM and ANFIS models and results are determined in terms of statistical measures like mean square error, root mean square error, correla-tion coefficient and scatter index. The result shows that soft computing techniques i.e., ANN, SVM and ANFIS can be efficient tools in predicting damage levels of non reshaped berm breakwater.

Pyviko: an automated Python tool to design gene knockouts in complex viruses with overlapping genes.

PubMed

Taylor, Louis J; Strebel, Klaus

2017-01-07

Gene knockouts are a common tool used to study gene function in various organisms. However, designing gene knockouts is complicated in viruses, which frequently contain sequences that code for multiple overlapping genes. Designing mutants that can be traced by the creation of new or elimination of existing restriction sites further compounds the difficulty in experimental design of knockouts of overlapping genes. While software is available to rapidly identify restriction sites in a given nucleotide sequence, no existing software addresses experimental design of mutations involving multiple overlapping amino acid sequences in generating gene knockouts. Pyviko performed well on a test set of over 240,000 gene pairs collected from viral genomes deposited in the National Center for Biotechnology Information Nucleotide database, identifying a point mutation which added a premature stop codon within the first 20 codons of the target gene in 93.2% of all tested gene-overprinted gene pairs. This shows that Pyviko can be used successfully in a wide variety of contexts to facilitate the molecular cloning and study of viral overprinted genes. Pyviko is an extensible and intuitive Python tool for designing knockouts of overlapping genes. Freely available as both a Python package and a web-based interface ( http://louiejtaylor.github.io/pyViKO/ ), Pyviko simplifies the experimental design of gene knockouts in complex viruses with overlapping genes.

Online and offline peer led models against bullying and cyberbullying.

PubMed

Palladino, Benedetta Emanuela; Nocentini, Annalaura; Menesini, Ersilia

2012-11-01

The aim of the present study is to describe and evaluate an ongoing peer-led model against bullying and cyberbullying carried out with Italian adolescents. The evaluation of the project was made through an experimental design consisting of a pre-test and a post-test. Participants in the study were 375 adolescents (20.3% males), enrolled in 9th to 13th grades. The experimental group involved 231 students with 42 peer educators, and the control group involved 144 students. Results showed a significant decrease in the experimental group as compared to the control group for all the variables except for cyberbullying. Besides, in the experimental group we found a significant increase in adaptive coping strategies like problem solving and a significant decrease in maladaptive coping strategies like avoidance: these changes mediate the changes in the behavioural variables. In particular, the decrease in avoidance predicts the decrease in victimization and cybervictimization for peer educators and for the other students in the experimental classes whereas the increase in problem solving predicts the decrease in cyberbullying only in the peer educators group. Results are discussed following recent reviews on evidence based efficacy of peer led models.

Implementation of a Collaborative Series of Classroom-Based Undergraduate Research Experiences Spanning Chemical Biology, Biochemistry, and Neurobiology

PubMed Central

Kowalski, Jennifer R.; Hoops, Geoffrey C.; Johnson, R. Jeremy

2016-01-01

Classroom undergraduate research experiences (CUREs) provide students access to the measurable benefits of undergraduate research experiences (UREs). Herein, we describe the implementation and assessment of a novel model for cohesive CUREs focused on central research themes involving faculty research collaboration across departments. Specifically, we implemented three collaborative CUREs spanning chemical biology, biochemistry, and neurobiology that incorporated faculty members’ research interests and revolved around the central theme of visualizing biological processes like Mycobacterium tuberculosis enzyme activity and neural signaling using fluorescent molecules. Each CURE laboratory involved multiple experimental phases and culminated in novel, open-ended, and reiterative student-driven research projects. Course assessments showed CURE participation increased students’ experimental design skills, attitudes and confidence about research, perceived understanding of the scientific process, and interest in science, technology, engineering, and mathematics disciplines. More than 75% of CURE students also engaged in independent scientific research projects, and faculty CURE contributors saw substantial increases in research productivity, including increased undergraduate student involvement and academic outputs. Our collaborative CUREs demonstrate the advantages of multicourse CUREs for achieving increased faculty research productivity and traditional CURE-associated student learning and attitude gains. Our collaborative CURE design represents a novel CURE model for ongoing laboratory reform that benefits both faculty and students. PMID:27810870

Optimum Tolerance Design Using Component-Amount and Mixture-Amount Experiments

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

Piepel, Gregory F.; Ozler, Cenk; Sehirlioglu, Ali Kemal

2013-08-01

One type of tolerance design problem involves optimizing component and assembly tolerances to minimize the total cost (sum of manufacturing cost and quality loss). Previous literature recommended using traditional response surface (RS) designs and models to solve this type of tolerance design problem. In this article, component-amount (CA) and mixture-amount (MA) approaches are proposed as more appropriate for solving this type of tolerance design problem. The advantages of the CA and MA approaches over the RS approach are discussed. Reasons for choosing between the CA and MA approaches are also discussed. The CA and MA approaches (experimental design, response modeling,more » and optimization) are illustrated using real examples.« less

Comparative Cognitive Task Analyses of Experimental Science and Instructional Laboratory Courses

NASA Astrophysics Data System (ADS)

Wieman, Carl

2015-09-01

Undergraduate instructional labs in physics generate intense opinions. Their advocates are passionate as to their importance for teaching physics as an experimental activity and providing "hands-on" learning experiences, while their detractors (often but not entirely students) offer harsh criticisms that they are pointless, confusing and unsatisfying, and "cookbook." Here, both to help understand the reason for such discrepant views and to aid in the design of instructional lab courses, I compare the mental tasks or types of thinking ("cognitive task analysis") associated with a physicist doing tabletop experimental research with the cognitive tasks of students in an introductory physics instructional lab involving traditional verification/confirmation exercises.

The Design of an Interface to a Programming System and MENUNIX: A Menu-Based Interface to UNIX (User Manual). Two Papers in Cognitive Engineering. Technical Report No. 8105.

ERIC Educational Resources Information Center

Perlman, Gary

This report consists of two papers on MENUNIX, an experimental interface to the approximately 300 programs and files available on the Berkeley UNIX 4.0 version of the UNIX operating system. The first paper discusses some of the psychological concerns involved in the design of MENUNIX; the second is a tutorial user manual for MENUNIX, in which the…

Understanding the effectiveness of the entertainment-education strategy: an investigation of how audience involvement, message processing, and message design influence health information recall.

PubMed

Quintero Johnson, Jessie M; Harrison, Kristen; Quick, Brian L

2013-01-01

A growing body of evidence suggests that entertainment-education (EE) is a promising health communication strategy. The purpose of this study was to identify some of the factors that facilitate and hinder audience involvement with EE messages. Using confirmatory factor analysis, the authors introduce a construct they call experiential involvement, which describes the experience of being cognitively and emotionally involved with EE messages and is a product of transportation into an EE text and identification with EE characters. Using an experimental design, the authors also investigated how reports of experiential involvement and health information recall varied depending on the degree to which the educational content was well integrated with the narrative content in EE messages. Findings indicated that integration significantly influenced health information recall. Results indicated that experiential involvement and the perception that the health topic in EE messages was personally relevant predicted participants' systematic processing of the information in EE messages. Contrary to expectation, personal relevance did not predict experiential involvement, and systematic message processing was negatively related to health information recall. Implications for the construction of EE messages and the study of the EE strategy are discussed.

Pure moment testing for spinal biomechanics applications: Fixed versus sliding ring cable-driven test designs.

PubMed

Eguizabal, Johnny; Tufaga, Michael; Scheer, Justin K; Ames, Christopher; Lotz, Jeffrey C; Buckley, Jenni M

2010-05-07

In vitro multi-axial bending testing using pure moment loading conditions has become the standard in evaluating the effects of different types of surgical intervention on spinal kinematics. Simple, cable-driven experimental set-ups have been widely adopted because they require little infrastructure. Traditionally, "fixed ring" cable-driven experimental designs have been used; however, there have been concerns with the validity of this set-up in applying pure moment loading. This study involved directly comparing the loading state induced by a traditional "fixed ring" apparatus versus a novel "sliding ring" approach. Flexion-extension bending was performed on an artificial spine model and a single cadaveric test specimen, and the applied loading conditions to the specimen were measured with an in-line multiaxial load cell. The results showed that the fixed ring system applies flexion-extension moments that are 50-60% less than the intended values. This design also imposes non-trivial anterior-posterior shear forces, and non-uniform loading conditions were induced along the length of the specimen. The results of this study indicate that fixed ring systems have the potential to deviate from a pure moment loading state and that our novel sliding ring modification corrects this error in the original test design. This suggests that the proposed sliding ring design should be used for future in vitro spine biomechanics studies involving a cable-driven pure moment apparatus. Copyright 2010 Elsevier Ltd. All rights reserved.

Identifying Effective Design Approaches to Allocate Genotypes in Two-Phase Designs: A Case Study in Pelargonium zonale

PubMed Central

Molenaar, Heike; Boehm, Robert; Piepho, Hans-Peter

2018-01-01

Robust phenotypic data allow adequate statistical analysis and are crucial for any breeding purpose. Such data is obtained from experiments laid out to best control local variation. Additionally, experiments frequently involve two phases, each contributing environmental sources of variation. For example, in a former experiment we conducted to evaluate production related traits in Pelargonium zonale, there were two consecutive phases, each performed in a different greenhouse. Phase one involved the propagation of the breeding strains to obtain the stem cutting count, and phase two involved the assessment of root formation. The evaluation of the former study raised questions regarding options for improving the experimental layout: (i) Is there a disadvantage to using exactly the same design in both phases? (ii) Instead of generating a separate layout for each phase, can the design be optimized across both phases, such that the mean variance of a pair-wise treatment difference (MVD) can be decreased? To answer these questions, alternative approaches were explored to generate two-phase designs either in phase-wise order (Option 1) or across phases (Option 2). In Option 1 we considered the scenarios (i) using in both phases the same experimental design and (ii) randomizing each phase separately. In Option 2, we considered the scenarios (iii) generating a single design with eight replicates and splitting these among the two phases, (iv) separating the block structure across phases by dummy coding, and (v) design generation with optimal alignment of block units in the two phases. In both options, we considered the same or different block structures in each phase. The designs were evaluated by the MVD obtained by the intra-block analysis and the joint inter-block–intra-block analysis. The smallest MVD was most frequently obtained for designs generated across phases rather than for each phase separately, in particular when both phases of the design were separated with a single pseudo-level. The joint optimization ensured that treatment concurrences were equally balanced across pairs, one of the prerequisites for an efficient design. The proposed alternative approaches can be implemented with any model-based design packages with facilities to formulate linear models for treatment and block structures. PMID:29354145

Torsion Tests of Stiffened Circular Cylinders

NASA Technical Reports Server (NTRS)

Moore, R L; Wescoat, C

1944-01-01

The design of curved sheet panels to resist shear involves a consideration of several factors: the buckling resistance of the sheet, the stress at which buckling becomes permanent, and the strength which may be developed beyond the buckling limit by tension-field action. Although some experimental as well as theoretical work has been done on the buckling and tension-field phases of this problem, neither of these types of action appears to be very well understood. The problem is of sufficient importance from the standpoint of aircraft design, it is believed, to warrant further experimental investigation. This report presents the results of the first series of torsion tests of stiffened circular cylinders to be completed in connection with this study at Aluminum Research Laboratories. (author)

Keeping the beat: use of rhythmic music during exercise activities for the elderly with dementia.

PubMed

Mathews, R M; Clair, A A; Kosloski, K

2001-01-01

Involving people with dementia in group exercise activities often presents a challenge. The effects of a recorded instrumental musical accompaniment was evaluated on participation in a series of 14 exercise activities with a group of nursing home residents with dementia. All exercise sessions, specifically designed by physical therapists for older adults, were lead by an activity aide and consisted of a series of seated exercises. Direct observations of resident behavior were conducted over a 25-week period in a reversal experimental design. Results showed increased levels of participation during the experimental condition observations where rhythmic music accompanied the exercise activities. The music intervention was most successful on those generally most willing to participate in social activities.

The Social Science Teacher; Vol. 4, No. 1, Summer 1974.

ERIC Educational Resources Information Center

Townley, Charles, Ed.

This new British journal is a medium of communication for those involved in teaching social science and social studies at the secondary and elementary levels. The first article in this issue, Ian Shelton's "The Sociology of Everyday Life," describes an experimental short course in secondary sociology. The course is designed to produce an…

Parent-Child Parallel-Group Intervention for Childhood Aggression in Hong Kong

ERIC Educational Resources Information Center

Fung, Annis L. C.; Tsang, Sandra H. K. M.

2006-01-01

This article reports the original evidence-based outcome study on parent-child parallel group-designed Anger Coping Training (ACT) program for children aged 8-10 with reactive aggression and their parents in Hong Kong. This research program involved experimental and control groups with pre- and post-comparison. Quantitative data collection…

Gaming via Computer Simulation Techniques for Junior College Economics Education. Final Report.

ERIC Educational Resources Information Center

Thompson, Fred A.

A study designed to answer the need for more attractive and effective economics education involved the teaching of one junior college economics class by the conventional (lecture) method and an experimental class by computer simulation techniques. Econometric models approximating the "real world" were computer programed to enable the experimental…

Enhancing Eight Grade Students' Scientific Conceptual Change and Scientific Reasoning through a Web-Based Learning Program

ERIC Educational Resources Information Center

Liao, Ya-Wen; She, Hsiao-Ching

2009-01-01

This study reports the impacts of the Scientific Concept Construction and Reconstruction (SCCR) digital learning system on eighth grade students' concept construction, conceptual change, and scientific reasoning involving the topic of "atoms". A two-factorial experimental design was carried out to investigate the effects of the approach…

Effects of Graphic Organiser on Students' Achievement in Algebraic Word Problems

ERIC Educational Resources Information Center

Owolabi, Josiah; Adaramati, Tobiloba Faith

2015-01-01

This study investigated the effects of graphic organiser and gender on students' academic achievement in algebraic word problem. Three research questions and three null hypotheses were used in guiding this study. Quasi experimental research was employed and Non-equivalent pre and post test design was used. The study involved the Senior Secondary…

MAP Markers: Research and Evaluation of the Mutual Agreement Program. Resource Document No. 5.

ERIC Educational Resources Information Center

Robison, James O.

This report is an evaluation, using randomized experimental/control design, of a program involving negotiated contractual agreements (MAP) between prisoners and parole boards for specific parole dates contingent on performance in work, training and treatment activities. Contracts were generally for less than six months. Both feasibility and…

Cooperative Learning and Learning Achievement in Social Science Subjects for Sociable Students

ERIC Educational Resources Information Center

Herpratiwi; Darsono; Sasmiati; Pujiyatli

2018-01-01

Purpose: The research objective was to compare students' learning achievement for sociable learning motivation students in social science (IPS) using cooperative learning. Research Methods: This research used a quasi-experimental method with a pre-test/post-test design involving 35 fifth-grade students. The learning process was conducted four…

Why Traditional Expository Teaching-Learning Approaches May Founder? An Experimental Examination of Neural Networks in Biology Learning

ERIC Educational Resources Information Center

Lee, Jun-Ki; Kwon, Yong-Ju

2011-01-01

Using functional magnetic resonance imaging (fMRI), this study investigates and discusses neurological explanations for, and the educational implications of, the neural network activations involved in hypothesis-generating and hypothesis-understanding for biology education. Two sets of task paradigms about biological phenomena were designed:…

A Meta-Analysis of Referential Communication Studies: A Computer Readable Literature Review.

ERIC Educational Resources Information Center

Dickson, W. Patrick; Moskoff, Mary

A computer-assisted analysis of studies on referential communication (giving directions/explanations) located 66 reports involving 80 experiments, 114 referential tasks, and over 6,200 individuals. The studies were entered into a statistical software package system (SPSS) and analyzed for characteristics of the subjects and experimental designs,…

Colour and Light Effects on Students' Achievement, Behavior and Physiology.

ERIC Educational Resources Information Center

Wohlfarth, H.

A quasi-experimental non-equivalent control group design was used to investigate the effects of full-spectrum light, prescribed color and light/color combinations, ultra-violet light, and electromagnetic radiation in an elementary school environment. Four schools in the Wetaskiwin School District, Alberta, were involved in the study; three served…

A Naturalistic Alcohol Availability Experiment: Effects on Crime.

ERIC Educational Resources Information Center

Kraushaar, Kevin; Alsop, Brent

Previous investigators have looked at many types of criminal offenses in order to determine alcohol involvement in crime. This longitudinal (4-year) naturalistic experimental and control designed study examined the effects of change in alcohol availability on rates of offending in a small provincial region of New Zealand following the closure of…

Factors that Enhance English-Speaking Speech-Language Pathologists' Transcription of Cantonese-Speaking Children's Consonants

ERIC Educational Resources Information Center

Lockart, Rebekah; McLeod, Sharynne

2013-01-01

Purpose: To investigate speech-language pathology students' ability to identify errors and transcribe typical and atypical speech in Cantonese, a nonnative language. Method: Thirty-three English-speaking speech-language pathology students completed 3 tasks in an experimental within-subjects design. Results: Task 1 (baseline) involved transcribing…

Newspapers in Science Education: A Study Involving Sixth Grade Students

ERIC Educational Resources Information Center

Lai, Ching-San; Wang, Yun-Fei

2016-01-01

The purpose of this study was to explore the learning performance of sixth grade elementary school students using newspapers in science teaching. A quasi-experimental design with a single group was used in this study. Thirty-three sixth grade elementary school students participated in this study. The research instruments consisted of three…

Triple Scheme of Learning Support Design for Scientific Discovery Learning Based on Computer Simulation: Experimental Research

ERIC Educational Resources Information Center

Zhang, Jianwei; Chen, Qi; Sun, Yanquing; Reid, David J.

2004-01-01

Learning support studies involving simulation-based scientific discovery learning have tended to adopt an ad hoc strategies-oriented approach in which the support strategies are typically pre-specified according to learners' difficulties in particular activities. This article proposes a more integrated approach, a triple scheme for learning…

An Experimental Study of Interference between Receptive and Productive Processes Involving Speech

ERIC Educational Resources Information Center

Goldman-Eisler, Frieda; Cohen, Michele

1975-01-01

Reports an experiment designed to throw light on the interference between the reception and production of speech by controlling the level of interference between decoding and encoding, using hesitancy as an indicator of interference. This proved effective in spotting the levels at which interference takes place. (Author/RM)

The feasibility of an efficient drug design method with high-performance computers.

PubMed

Yamashita, Takefumi; Ueda, Akihiko; Mitsui, Takashi; Tomonaga, Atsushi; Matsumoto, Shunji; Kodama, Tatsuhiko; Fujitani, Hideaki

2015-01-01

In this study, we propose a supercomputer-assisted drug design approach involving all-atom molecular dynamics (MD)-based binding free energy prediction after the traditional design/selection step. Because this prediction is more accurate than the empirical binding affinity scoring of the traditional approach, the compounds selected by the MD-based prediction should be better drug candidates. In this study, we discuss the applicability of the new approach using two examples. Although the MD-based binding free energy prediction has a huge computational cost, it is feasible with the latest 10 petaflop-scale computer. The supercomputer-assisted drug design approach also involves two important feedback procedures: The first feedback is generated from the MD-based binding free energy prediction step to the drug design step. While the experimental feedback usually provides binding affinities of tens of compounds at one time, the supercomputer allows us to simultaneously obtain the binding free energies of hundreds of compounds. Because the number of calculated binding free energies is sufficiently large, the compounds can be classified into different categories whose properties will aid in the design of the next generation of drug candidates. The second feedback, which occurs from the experiments to the MD simulations, is important to validate the simulation parameters. To demonstrate this, we compare the binding free energies calculated with various force fields to the experimental ones. The results indicate that the prediction will not be very successful, if we use an inaccurate force field. By improving/validating such simulation parameters, the next prediction can be made more accurate.

Method Improving Reading Comprehension In Primary Education Program Students

NASA Astrophysics Data System (ADS)

Rohana

2018-01-01

This study aims to determine the influence of reading comprehension skills of English for PGSD students through the application of SQ3R learning method. The type of this research is Pre-Experimental research because it is not yet a real experiment, there are external variables that influence the formation of a dependent variable, this is because there is no control variable and the sample is not chosen randomly. The research design is used is one-group pretest-post-test design involving one group that is an experimental group. In this design, the observation is done twice before and after the experiment. Observations made before the experiment (O1) are called pretests and the post-experimental observation (O2) is called posttest. The difference between O1 and O2 ie O2 - O1 is the effect of the treatment. The results showed that there was an improvement in reading comprehension skills of PGSD students in Class M.4.3 using SQ3R method, and better SQ3R enabling SQ3R to improve English comprehension skills.

Establishing a `Centre for Engineering Experimentation and Design Simulation': a step towards restructuring engineering education in India

NASA Astrophysics Data System (ADS)

Venkateswarlu, P.

2017-07-01

Reforms in undergraduate engineering curriculum to produce engineers with entrepreneurial skills should address real-world problems relevant to industry and society with active industry support. Technology-assisted, hands-on projects involving experimentation, design simulation and prototyping will transform graduates into professionals with necessary skills to create and advance knowledge that meets global standards. To achieve this goal, this paper proposes establishing a central facility, 'Centre for Engineering Experimentation and Design Simulation' (CEEDS) in autonomous engineering colleges in India. The centre will be equipped with the most recent technology resources and computational facilities where students execute novel interdisciplinary product-oriented projects benefiting both industry and society. Students undertake two projects: a short-term project aimed at an engineering solution to a problem in energy, health and environment and the other a major industry-supported project devoted to a product that enhances innovation and creativity. The paper presents the current status, the theoretical and pedagogical foundation for the centre's relevance, an activity plan and its implementation in the centre for product-based learning with illustrative examples.

Reflections on experimental research in medical education.

PubMed

Cook, David A; Beckman, Thomas J

2010-08-01

As medical education research advances, it is important that education researchers employ rigorous methods for conducting and reporting their investigations. In this article we discuss several important yet oft neglected issues in designing experimental research in education. First, randomization controls for only a subset of possible confounders. Second, the posttest-only design is inherently stronger than the pretest-posttest design, provided the study is randomized and the sample is sufficiently large. Third, demonstrating the superiority of an educational intervention in comparison to no intervention does little to advance the art and science of education. Fourth, comparisons involving multifactorial interventions are hopelessly confounded, have limited application to new settings, and do little to advance our understanding of education. Fifth, single-group pretest-posttest studies are susceptible to numerous validity threats. Finally, educational interventions (including the comparison group) must be described in detail sufficient to allow replication.

Autogenic-Feedback Training (AFT) as a preventive method for space motion sickness: Background and experimental design

NASA Technical Reports Server (NTRS)

Cowings, Patricia S.; Toscano, William B.

1993-01-01

Finding an effective treatment for the motion sickness-like symptoms that occur in space has become a high priority for NASA. The background research is reviewed and the experimental design of a formal life sciences shuttle flight experiment designed to prevent space motion sickness in shuttle crew members is presented. This experiment utilizes a behavioral medicine approach to solving this problem. This method, Autogenic-Feedback Training (AFT), involves training subjects to voluntarily control several of their own physiological responses to environmental stressors. AFT has been used reliably to increase tolerance to motion sickness during ground-based tests in over 200 men and women under a variety of conditions that induce motion sickness, and preliminary evidence from space suggests that AFT may be an effective treatment for space motion sickness as well. Proposed changes to this experiment for future manifests are included.

Experimental demonstration of active vibration control for flexible structures

NASA Technical Reports Server (NTRS)

Phillips, Douglas J.; Hyland, David C.; Collins, Emmanuel G., Jr.

1990-01-01

Active vibration control of flexible structures for future space missions is addressed. Three experiments that successfully demonstrate control of flexible structures are described. The first is the pendulum experiment. The structure is a 5-m compound pendulum and was designed as an end-to-end test bed for a linear proof mass actuator and its supporting electronics. Experimental results are shown for a maximum-entropy/optimal-projection controller designed to achieve 5 percent damping in the first two pendulum modes. The second experiment was based upon the Harris Multi-Hex prototype experiment (MHPE) apparatus. This is a large optical reflector structure comprising a seven-panel array and supporting truss which typifies a number of generic characteristics of large space systems. The third experiment involved control design and implementation for the ACES structure at NASA Marshall Space Flight Center. The authors conclude with some remarks on the lessons learned from conducting these experiments.

Broadband polygonal invisibility cloak for visible light

PubMed Central

Chen, Hongsheng; Zheng, Bin

2012-01-01

Invisibility cloaks have recently become a topic of considerable interest thanks to the theoretical works of transformation optics and conformal mapping. The design of the cloak involves extreme values of material properties and spatially dependent parameter tensors, which are very difficult to implement. The realization of an isolated invisibility cloak in the visible light, which is an important step towards achieving a fully movable invisibility cloak, has remained elusive. Here, we report the design and experimental demonstration of an isolated polygonal cloak for visible light. The cloak is made of several elements, whose electromagnetic parameters are designed by a linear homogeneous transformation method. Theoretical analysis shows the proposed cloak can be rendered invisible to the rays incident from all the directions. Using natural anisotropic materials, a simplified hexagonal cloak which works for six incident directions is fabricated for experimental demonstration. The performance is validated in a broadband visible spectrum. PMID:22355767

Product design enhancement using apparent usability and affective quality.

PubMed

Seva, Rosemary R; Gosiaco, Katherine Grace T; Santos, Ma Crea Eurice D; Pangilinan, Denise Mae L

2011-03-01

In this study, apparent usability and affective quality were integrated in a design framework called the Usability Perception and Emotion Enhancement Model (UPEEM). The UPEEM was validated using structural equation modeling (SEM). The methodology consists of four phases namely product selection, attribute identification, design alternative generation, and design alternative evaluation. The first stage involved the selection of a product that highly involves the consumer. In the attribute identification stage, design elements of the product were identified. The possible values of these elements were also determined for use in the experimentation process. Design of experiments was used to identify how the attributes will be varied in the design alternative stage and which of the attributes significantly contribute to affective quality, apparent usability, and desirability in the design evaluation stage. Results suggest that product attributes related to form are relevant in eliciting intense affect and perception of usability in mobile phones especially those directly related to functionality and aesthetics. This study considered only four product attributes among so many due to the constraints of the research design employed. Attributes related to aesthetic perception of a product enhance apparent usability such as those related to dimensional ratios. Copyright © 2010 Elsevier Ltd and The Ergonomics Society. All rights reserved.

28th Lanchester Memorial Lecture - Experimental real-gas hypersonics

NASA Astrophysics Data System (ADS)

Hornung, H. G.

1988-12-01

It is possible to simulate a number of dissociative real-gas effects in the laboratory by means quite different from those of the perfect-gas Mach-Reynolds simulation, as presently demonstrated for two sets of results obtained in a free-piston shock tunnel experimental facility designed and built for this purpose. The results concern blunt body flows, which involve the phenomenon of dissociation quenching, and shock detachment from a wedge, which revealed a novel effect of reacting flows in which a thin subsonic layer exists after the shock, followed by a supersonic flow.

Buoyancy-Driven Instabilities in Single-Bubble Sonoluminescence

NASA Technical Reports Server (NTRS)

Matula, Thomas J.

2003-01-01

The principal objectives of this study are to determine how gravity affects the emission of light from single-bubble sonoluminescence (SBSL), and whether or not the bubble extinction is directly related to gravity. Our experimental task involves designing glass or quartz spherical levitation cells that generate very stable SL bubbles. The cells must have minimized vibration, and some temperature control. The experimental system will reside in a light-tight enclosure. Aside from acceleration, the frequency, pressure amplitude, and light intensity must be measured. A computer program will be constructed to perform all aspects of the experiment.

Investigating the Energetic Ordering of Stable and Metastable TiO 2 Polymorphs Using DFT+ U and Hybrid Functionals

DOE PAGES

Curnan, Matthew T.; Kitchin, John R.

2015-08-12

Prediction of transition metal oxide BO 2 (B = Ti, V, etc.) polymorph energetic properties is critical to tunable material design and identifying thermodynamically accessible structures. Determining procedures capable of synthesizing particular polymorphs minimally requires prior knowledge of their relative energetic favorability. Information concerning TiO 2 polymorph relative energetic favorability has been ascertained from experimental research. In this study, the consistency of first-principles predictions and experimental results involving the relative energetic ordering of stable (rutile), metastable (anatase and brookite), and unstable (columbite) TiO 2 polymorphs is assessed via density functional theory (DFT). Considering the issues involving electron–electron interaction and chargemore » delocalization in TiO 2 calculations, relative energetic ordering predictions are evaluated over trends varying Ti Hubbard U 3d or exact exchange fraction parameter values. Energetic trends formed from varying U 3d predict experimentally consistent energetic ordering over U 3d intervals when using GGA-based functionals, regardless of pseudopotential selection. Given pertinent linear response calculated Hubbard U values, these results enable TiO 2 polymorph energetic ordering prediction. Here, the hybrid functional calculations involving rutile–anatase relative energetics, though demonstrating experimentally consistent energetic ordering over exact exchange fraction ranges, are not accompanied by predicted fractions, for a first-principles methodology capable of calculating exact exchange fractions precisely predicting TiO 2 polymorph energetic ordering is not available.« less

Understanding the role consumer involvement plays in the effectiveness of hospital advertising.

PubMed

McCullough, Tammy; Dodge, H Robert

2002-01-01

Both intensified competition and greater consumer participation in the choice process for healthcare has increased the importance of advertising for health care providers and seriously challenged many of the preconceptions regarding advertising. This study investigates the effectiveness of advertising under conditions of high and low involvement using the Elaboration Likelihood Model to develop hypotheses that are tested in a 2 x 2 x 2 experimental design. The study findings provide insights into the influence of message content and message source on consumers categorized as high or low involvement. It was found that consumers classified as high-involvement are more influenced by a core service-relevant message than those consumers classified as low-involvement. Moreover, a non-physician spokesperson was found to have as much or more influence as a physician spokesperson regardless of the consumers' involvement level.

Exploring the relationship between time management skills and the academic achievement of African engineering students - a case study

NASA Astrophysics Data System (ADS)

Swart, Arthur James; Lombard, Kobus; de Jager, Henk

2010-03-01

Poor academic success by African engineering students is currently experienced in many higher educational institutions, contributing to lower financial subsidies by local governments. One of the contributing factors to this low academic success may be the poor time management skills of these students. This article endeavours to explore this relationship by means of a theoretical literature review and an empirical study. Numerous studies have been conducted in this regard, but with mixed results. The case study of this article involves a design module termed Design Projects III, where the empirical study incorporated an ex post facto study involving a pre-experimental/exploratory design using descriptive statistics. The results of this study were applied to various tests, which indicated no statistically significant relationship between time management skills and the academic achievement of African engineering students.

The use of control groups in music therapy research: a content analysis of articles in the Journal of Music Therapy.

PubMed

Jones, Jennifer D

2006-01-01

The use of a control group is fundamental to experimental research design, though the use with clinical populations must be carefully considered. The purpose of this research was to examine the use of control groups in research with clinical and nonclinical populations published in Journal of Musical Therapy from 1964 through 2004. Criteria for inclusion were music or music therapy as an independent variable applied to one or more groups and at least one control group that did not receive a music treatment. Control groups were qualified as alternative treatment, placebo, no contact, and treatment as usual. Of the 692 articles, 94 met these criteria, 62 clinical and 32 nonclinical, representing 13.5% of the publications. Results indicated that research with clinical populations involved a mean of 38.1 subjects typically divided into two groups, an experimental and a control group. The pretest-posttest design was the most common (55%) as was a treatment as usual control group (45%). These design methods maximized the impact of the experimental music treatment on outcome. Experimental music groups significantly improved over control groups in the vast majority of studies identified. Undoubtedly, the foundation for evidence-based clinical practice is firm.

Entropy-Based Search Algorithm for Experimental Design

NASA Astrophysics Data System (ADS)

Malakar, N. K.; Knuth, K. H.

2011-03-01

The scientific method relies on the iterated processes of inference and inquiry. The inference phase consists of selecting the most probable models based on the available data; whereas the inquiry phase consists of using what is known about the models to select the most relevant experiment. Optimizing inquiry involves searching the parameterized space of experiments to select the experiment that promises, on average, to be maximally informative. In the case where it is important to learn about each of the model parameters, the relevance of an experiment is quantified by Shannon entropy of the distribution of experimental outcomes predicted by a probable set of models. If the set of potential experiments is described by many parameters, we must search this high-dimensional entropy space. Brute force search methods will be slow and computationally expensive. We present an entropy-based search algorithm, called nested entropy sampling, to select the most informative experiment for efficient experimental design. This algorithm is inspired by Skilling's nested sampling algorithm used in inference and borrows the concept of a rising threshold while a set of experiment samples are maintained. We demonstrate that this algorithm not only selects highly relevant experiments, but also is more efficient than brute force search. Such entropic search techniques promise to greatly benefit autonomous experimental design.

Experimental Supersonic Combustion Research at NASA Langley

NASA Technical Reports Server (NTRS)

Rogers, R. Clayton; Capriotti, Diego P.; Guy, R. Wayne

1998-01-01

Experimental supersonic combustion research related to hypersonic airbreathing propulsion has been actively underway at NASA Langley Research Center (LaRC) since the mid-1960's. This research involved experimental investigations of fuel injection, mixing, and combustion in supersonic flows and numerous tests of scramjet engine flowpaths in LaRC test facilities simulating flight from Mach 4 to 8. Out of this research effort has come scramjet combustor design methodologies, ground test techniques, and data analysis procedures. These technologies have progressed steadily in support of the National Aero-Space Plane (NASP) program and the current Hyper-X flight demonstration program. During NASP nearly 2500 tests of 15 scramjet engine models were conducted in LaRC facilities. In addition, research supporting the engine flowpath design investigated ways to enhance mixing, improve and apply nonintrusive diagnostics, and address facility operation. Tests of scramjet combustor operation at conditions simulating hypersonic flight at Mach numbers up to 17 also have been performed in an expansion tube pulse facility. This paper presents a review of the LaRC experimental supersonic combustion research efforts since the late 1980's, during the NASP program, and into the Hyper-X Program.

Studying technology use as social practice: the untapped potential of ethnography

PubMed Central

2011-01-01

Information and communications technologies (ICTs) in healthcare are often introduced with expectations of higher-quality, more efficient, and safer care. Many fail to meet these expectations. We argue here that the well-documented failures of ICTs in healthcare are partly attributable to the philosophical foundations of much health informatics research. Positivistic assumptions underpinning the design, implementation and evaluation of ICTs (in particular the notion that technology X has an impact which can be measured and reproduced in new settings), and the deterministic experimental and quasi-experimental study designs which follow from these assumptions, have inherent limitations when ICTs are part of complex social practices involving multiple human actors. We suggest that while experimental and quasi-experimental studies have an important place in health informatics research overall, ethnography is the preferred methodological approach for studying ICTs introduced into complex social systems. But for ethnographic approaches to be accepted and used to their full potential, many in the health informatics community will need to revisit their philosophical assumptions about what counts as research rigor. PMID:21521535

Educated Guesses and Other Ways to Address the Pharmacological Uncertainty of Designer Drugs

PubMed Central

Berning, Moritz

2016-01-01

This study examines how experimentation with designer drugs is mediated by the Internet. We selected a popular drug forum that presents reports on self-experimentation with little or even completely unexplored designer drugs to examine: (1) how participants report their “trying out” of new compounds and (2) how participants reduce the pharmacological uncertainty associated with using these substances. Our methods included passive observation online, engaging more actively with the online community using an avatar, and off-line interviews with key interlocutors to validate our online findings. This article reflects on how forum participants experiment with designer drugs, their trust in suppliers and the testimonials of others, the use of ethno-scientific techniques that involve numerical weighing, “allergy dosing,” and the use of standardized trip reports. We suggest that these techniques contribute to a sense of control in the face of the possible toxicity of unknown or little-known designer drugs. The online reporting of effects allows users to experience not only the thrill of a new kind of high but also connection with others in the self-experimenting drug community. PMID:27721526

Estimating the effect of gang membership on nonviolent and violent delinquency: a counterfactual analysis.

PubMed

Barnes, J C; Beaver, Kevin M; Miller, J Mitchell

2010-01-01

This study reconsiders the well-known link between gang membership and criminal involvement. Recently developed analytical techniques enabled the approximation of an experimental design to determine whether gang members, after being matched with similarly situated nongang members, exhibited greater involvement in nonviolent and violent delinquency. Findings indicated that while gang membership is a function of self-selection, selection effects alone do not account for the greater involvement in delinquency exhibited by gang members. After propensity score matching was employed, gang members maintained a greater involvement in both nonviolent and violent delinquency when measured cross-sectionally, but only violent delinquency when measured longitudinally. Additional analyses using inverse probability of treatment weights reaffirmed these conclusions. © 2010 Wiley-Liss, Inc.

Old Wine in New Skins: The Sensitivity of Established Findings to New Methods

ERIC Educational Resources Information Center

Foster, E. Michael; Wiley-Exley, Elizabeth; Bickman, Leonard

2009-01-01

Findings from an evaluation of a model system for delivering mental health services to youth were reassessed to determine the robustness of key findings to the use of methodologies unavailable to the original analysts. These analyses address a key concern about earlier findings--that the quasi-experimental design involved the comparison of two…

Science Experiments on File. Experiments, Demonstrations and Projects for School and Home.

ERIC Educational Resources Information Center

Tyler, Vicki, Ed.

This book, addressed to students for their independent use as well as to teachers as a supplement to the standard texts, contains nearly 100 practical science experiments that cover a wide range of subjects at different grade and ability levels. It is designed to involve students in active scientific experimentation, demonstrations, and projects…

Energy: Light, Sound, and Heat, Science (Experimental): 5311.04.

ERIC Educational Resources Information Center

Castaldi, June P.

This unit of instruction was designed as a basic course involving the study of light, sound, and heat at the junior high school level. The booklet lists the relevant state-adopted texts and states the performance objectives for the unit. It provides an outline of the course content and suggests experiments, demonstrations, field trips, and topics…

Mind the Gap! Students' Use of Exemplars and Detailed Rubrics as Formative Assessment

ERIC Educational Resources Information Center

Lipnevich, Anastasiya A.; McCallen, Leigh N.; Miles, Katharine Pace; Smith, Jeffrey K.

2014-01-01

The current study examined efficient modes for providing standardized feedback to improve performance on an assignment for a second year college class involving writing a brief research proposal. Two forms of standardized feedback (detailed rubric and proposal exemplars) were utilized is an experimental design with undergraduate students (N = 100)…

Introduction to the Plant World, Science (Experimental): 5311.11.

ERIC Educational Resources Information Center

Payne, Leonard O.

This unit of instruction was designed as a laboratory-oriented course for very low achievers to show how plants are involved in every aspect of their lives. Detailed practical experience in handling and investigating plants, and the use of films, models, and field trips are combined with basic minimal research to guide the student to a better…

Effects Of Rapid Crushing On Composites

NASA Technical Reports Server (NTRS)

Farley, Gary L.

1990-01-01

Experimental study described in NASA technical memorandum performed to determine whether crash energy-absorption capabilities of graphite/epoxy and Kevlar/epoxy composite materials are functions of speed of crushing. Additional objective to develop understanding of mechanisms of crushing. Technology applied to enhancement of safety and crashworthiness of automobiles, design of energy-absorbing devices in machinery, and problems involving explosions and impacts.

Promoting Psychosocial Adjustment and Stress Management in First-Year College Students: The Benefits of Engagement in a Psychosocial Wellness Seminar

ERIC Educational Resources Information Center

Conley, Colleen S.; Travers, Lea V.; Bryant, Fred B.

2013-01-01

Objective/Methods: This research evaluates the effectiveness of a psychosocial wellness seminar for first-year college students, from 2009 to 2011, using an 8-month prospective quasi-experimental design. Participants/Results: Compared with controls ("n" = 22) involved in an alternative seminar, intervention participants ("n" =…

Effects of Testwiseness Training in Mathematics on Adolescent Secondary School Students' Test Anxiety in Ondo State, Nigeria

ERIC Educational Resources Information Center

Gbore, Lawrence Olu; Osakuade, Joseph Oluwatayo

2016-01-01

This study investigated the effects of test-wiseness training in Mathematics on adolescent secondary school students' test anxiety. The research study adopted for the study was an experimental research that involved pretest, posttest and control groups design. One hundred and twenty (120) adolescent senior secondary school class three students of…

An Exploratory Comparison of Traditional Classroom Instruction and Anchored Instruction with Secondary School Students: Turkish Experience

ERIC Educational Resources Information Center

Elcin, Melih; Sezer, Baris

2014-01-01

The purpose of this study was to investigate the impact of anchored instruction on the students in secondary school math studies classrooms. This study adopted a quasi-experimental design. This research involved both quantitative and qualitative methods to investigate the effects of anchored instruction on students' academical achievement,…

A Healthier Workplace? Implementation of Fruit Boxes in the Workplace

ERIC Educational Resources Information Center

Pescud, Melanie; Waterworth, Pippa; Shilton, Trevor; Teal, Renee; Slevin, Terry; Ledger, Melissa; Lester, Leanne; Rosenberg, Michael

2016-01-01

Objective: The purpose of this study was to investigate whether making fruit boxes available in the workplace is a successful health promotion strategy. Design: A quasi-experimental study involving three conditions--free fruit, 50c per piece of fruit and $1 per piece of fruit--to investigate the effect of a contribution scheme on employees' fruit…

An Inquiry-Based Practical for a Large, Foundation-Level Undergraduate Laboratory that Enhances Student Understanding of Basic Cellular Concepts and Scientific Experimental Design

ERIC Educational Resources Information Center

Bugarcic, A.; Zimbardi, K.; Macaranas, J.; Thorn, P.

2012-01-01

Student-centered education involving research experiences or inquiry have been shown to help undergraduate students understand, and become excited about, the process of scientific investigation. These benefits are particularly important for students in the early stages of their degree (Report and Kenny,…

E-Readers and the Effects on Students' Reading Motivation, Attitude, and Comprehension

ERIC Educational Resources Information Center

Long, Deanna

2014-01-01

The purpose of this study was to determine if the use of E-readers during guided reading instruction would affect students' reading motivation, attitude toward reading, and reading comprehension. The study utilized on a quasi-experimental mixed methods research design that involved 35 fifth grade students in two fifth grade reading classes. For 10…

Enhancing Vocabulary and Writing Skills through Digital Storytelling in Higher Education

ERIC Educational Resources Information Center

Tajeri, Mojtaba; Syal, Pushpinder; Marzban, Sanaz

2017-01-01

The purpose of this study was to examine the benefits of using Digital Storytelling (DST) in language classes in higher education. The study also aims to explore the appropriate classroom activities which assist language teaching and learning. The thirteen-week study adopted a pretest and posttest quasi-experimental design involving a group of 20…

North Carolina State Supported Early Childhood Demonstration Centers. Second Annual Evaluation: 1970-1971.

ERIC Educational Resources Information Center

Learning Inst. of North Carolina, Durham.

The second year of a state supported early childhood education program was evaluated, using a pre-post evaluation design involving experimental and control groups. An Early Childhood Assessment Battery was administered to 720 five-year-olds enrolled in the kindergarten program by their teachers. The control group (178) were tested locally. Results…

Social Identity Change: Shifts in Social Identity during Adolescence

ERIC Educational Resources Information Center

Tanti, Chris; Stukas, Arthur A.; Halloran, Michael J.; Foddy, Margaret

2011-01-01

This study investigated the proposition that adolescence involves significant shifts in social identity as a function of changes in social context and cognitive style. Using an experimental design, we primed either peer or gender identity with a sample of 380 early- (12-13 years), mid- (15-16 years), and late-adolescents (18-20 years) and then…

The Modern Design of Experiments for Configuration Aerodynamics: A Case Study

NASA Technical Reports Server (NTRS)

DeLoach, Richard

2006-01-01

The effects of slowly varying and persisting covariate effects on the accuracy and precision of experimental result is reviewed, as is the rationale for run-order randomization as a quality assurance tactic employed in the Modern Design of Experiments (MDOE) to defend against such effects. Considerable analytical complexity is introduced by restrictions on randomization in configuration aerodynamics tests because they involve hard-to-change configuration variables that cannot be randomized conveniently. Tradeoffs are examined between quality and productivity associated with varying degrees of rigor in accounting for such randomization restrictions. Certain characteristics of a configuration aerodynamics test are considered that may justify a relaxed accounting for randomization restrictions to achieve a significant reduction in analytical complexity with a comparably negligible adverse impact on the validity of the experimental results.

Parametric study of closed wet cooling tower thermal performance

NASA Astrophysics Data System (ADS)

Qasim, S. M.; Hayder, M. J.

2017-08-01

The present study involves experimental and theoretical analysis to evaluate the thermal performance of modified Closed Wet Cooling Tower (CWCT). The experimental study includes: design, manufacture and testing prototype of a modified counter flow forced draft CWCT. The modification based on addition packing to the conventional CWCT. A series of experiments was carried out at different operational parameters. In view of energy analysis, the thermal performance parameters of the tower are: cooling range, tower approach, cooling capacity, thermal efficiency, heat and mass transfer coefficients. The theoretical study included develops Artificial Neural Network (ANN) models to predicting various thermal performance parameters of the tower. Utilizing experimental data for training and testing, the models simulated by multi-layer back propagation algorithm for varying all operational parameters stated in experimental test.

Structural model of the hUbA1-UbcH10 quaternary complex: in silico and experimental analysis of the protein-protein interactions between E1, E2 and ubiquitin.

PubMed

Correale, Stefania; de Paola, Ivan; Morgillo, Carmine Marco; Federico, Antonella; Zaccaro, Laura; Pallante, Pierlorenzo; Galeone, Aldo; Fusco, Alfredo; Pedone, Emilia; Luque, F Javier; Catalanotti, Bruno

2014-01-01

UbcH10 is a component of the Ubiquitin Conjugation Enzymes (Ubc; E2) involved in the ubiquitination cascade controlling the cell cycle progression, whereby ubiquitin, activated by E1, is transferred through E2 to the target protein with the involvement of E3 enzymes. In this work we propose the first three dimensional model of the tetrameric complex formed by the human UbA1 (E1), two ubiquitin molecules and UbcH10 (E2), leading to the transthiolation reaction. The 3D model was built up by using an experimentally guided incremental docking strategy that combined homology modeling, protein-protein docking and refinement by means of molecular dynamics simulations. The structural features of the in silico model allowed us to identify the regions that mediate the recognition between the interacting proteins, revealing the active role of the ubiquitin crosslinked to E1 in the complex formation. Finally, the role of these regions involved in the E1-E2 binding was validated by designing short peptides that specifically interfere with the binding of UbcH10, thus supporting the reliability of the proposed model and representing valuable scaffolds for the design of peptidomimetic compounds that can bind selectively to Ubcs and inhibit the ubiquitylation process in pathological disorders.

Designing a mixture experiment when the components are subject to a nonlinear multiple-component constraint

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

Piepel, Greg F.; Cooley, Scott K.; Vienna, John D.

This article presents a case study of developing an experimental design for a constrained mixture experiment when the experimental region is defined by single-component constraints (SCCs), linear multiple-component constraints (MCCs), and a nonlinear MCC. Traditional methods and software for designing constrained mixture experiments with SCCs and linear MCCs are not directly applicable because of the nonlinear MCC. A modification of existing methodology to account for the nonlinear MCC was developed and is described in this article. The case study involves a 15-component nuclear waste glass example in which SO3 is one of the components. SO3 has a solubility limit inmore » glass that depends on the composition of the balance of the glass. A goal was to design the experiment so that SO3 would not exceed its predicted solubility limit for any of the experimental glasses. The SO3 solubility limit had previously been modeled by a partial quadratic mixture (PQM) model expressed in the relative proportions of the 14 other components. The PQM model was used to construct a nonlinear MCC in terms of all 15 components. In addition, there were SCCs and linear MCCs. This article discusses the waste glass example and how a layered design was generated to (i) account for the SCCs, linear MCCs, and nonlinear MCC and (ii) meet the goals of the study.« less

Challenges for Preclinical Investigations of Human Biofield Modalities

PubMed Central

Gronowicz, Gloria; Bengston, William

2015-01-01

Preclinical models for studying the effects of the human biofield have great potential to advance our understanding of human biofield modalities, which include external qigong, Johrei, Reiki, therapeutic touch, healing touch, polarity therapy, pranic healing, and other practices. A short history of Western biofield studies using preclinical models is presented and demonstrates numerous and consistent examples of human biofields significantly affecting biological systems both in vitro and in vivo. Methodological issues arising from these studies and practical solutions in experimental design are presented. Important questions still left unanswered with preclinical models include variable reproducibility, dosing, intentionality of the practitioner, best preclinical systems, and mechanisms. Input from the biofield practitioners in the experimental design is critical to improving experimental outcomes; however, the development of standard criteria for uniformity of practice and for inclusion of multiple practitioners is needed. Research in human biofield studies involving preclinical models promises a better understanding of the mechanisms underlying the efficacy of biofield therapies and will be important in guiding clinical protocols and integrating treatments with conventional medical therapies. PMID:26665042

Implementation and outcome evaluation of high-fidelity simulation scenarios to integrate cognitive and psychomotor skills for Korean nursing students.

PubMed

Ahn, Heejung; Kim, Hyun-Young

2015-05-01

This study is involved in designing high-fidelity simulations reflecting the Korean nursing education environment. In addition, it evaluated the simulations by nursing students' learning outcomes and perceptions of the simulation design features. A quantitative design was used in two separate phases. For the first phase, five nursing experts participated in verifying the appropriateness of two simulation scenarios that reflected the intended learning objectives. For the second phase, 69 nursing students in the third year of a bachelor's degree at a nursing school participated in evaluating the simulations and were randomized according to their previous course grades. The first phase verified the two simulation scenarios using a questionnaire. The second phase evaluated students' perceptions of the simulation design, self-confidence, and critical thinking skills using a quasi-experimental post-test design. ANCOVA was used to compare the experimental and control groups, and correlation coefficient analysis was used to determine the correlation among them. We created 2 simulation scenarios to integrate cognitive and psychomotor skills according to the learning objectives and clinical environment in Korea. The experimental group had significantly higher scores on self-confidence in the first scenario. The positive correlations between perceptions of the simulation design features, self-confidence, and critical thinking skill scores were statistically significant. Students with a more positive perception of the design features of the simulations had better learning outcomes. Based on this result, simulations need to be designed and implemented with more differentiation in order to be perceived more appropriately by students. Copyright © 2015 Elsevier Ltd. All rights reserved.

An Intelligent Automation Platform for Rapid Bioprocess Design.

PubMed

Wu, Tianyi; Zhou, Yuhong

2014-08-01

Bioprocess development is very labor intensive, requiring many experiments to characterize each unit operation in the process sequence to achieve product safety and process efficiency. Recent advances in microscale biochemical engineering have led to automated experimentation. A process design workflow is implemented sequentially in which (1) a liquid-handling system performs high-throughput wet lab experiments, (2) standalone analysis devices detect the data, and (3) specific software is used for data analysis and experiment design given the user's inputs. We report an intelligent automation platform that integrates these three activities to enhance the efficiency of such a workflow. A multiagent intelligent architecture has been developed incorporating agent communication to perform the tasks automatically. The key contribution of this work is the automation of data analysis and experiment design and also the ability to generate scripts to run the experiments automatically, allowing the elimination of human involvement. A first-generation prototype has been established and demonstrated through lysozyme precipitation process design. All procedures in the case study have been fully automated through an intelligent automation platform. The realization of automated data analysis and experiment design, and automated script programming for experimental procedures has the potential to increase lab productivity. © 2013 Society for Laboratory Automation and Screening.

An Intelligent Automation Platform for Rapid Bioprocess Design

PubMed Central

Wu, Tianyi

2014-01-01

Bioprocess development is very labor intensive, requiring many experiments to characterize each unit operation in the process sequence to achieve product safety and process efficiency. Recent advances in microscale biochemical engineering have led to automated experimentation. A process design workflow is implemented sequentially in which (1) a liquid-handling system performs high-throughput wet lab experiments, (2) standalone analysis devices detect the data, and (3) specific software is used for data analysis and experiment design given the user’s inputs. We report an intelligent automation platform that integrates these three activities to enhance the efficiency of such a workflow. A multiagent intelligent architecture has been developed incorporating agent communication to perform the tasks automatically. The key contribution of this work is the automation of data analysis and experiment design and also the ability to generate scripts to run the experiments automatically, allowing the elimination of human involvement. A first-generation prototype has been established and demonstrated through lysozyme precipitation process design. All procedures in the case study have been fully automated through an intelligent automation platform. The realization of automated data analysis and experiment design, and automated script programming for experimental procedures has the potential to increase lab productivity. PMID:24088579

Mechanical-Kinetic Modeling of a Molecular Walker from a Modular Design Principle

NASA Astrophysics Data System (ADS)

Hou, Ruizheng; Loh, Iong Ying; Li, Hongrong; Wang, Zhisong

2017-02-01

Artificial molecular walkers beyond burnt-bridge designs are complex nanomachines that potentially replicate biological walkers in mechanisms and functionalities. Improving the man-made walkers up to performance for widespread applications remains difficult, largely because their biomimetic design principles involve entangled kinetic and mechanical effects to complicate the link between a walker's construction and ultimate performance. Here, a synergic mechanical-kinetic model is developed for a recently reported DNA bipedal walker, which is based on a modular design principle, potentially enabling many directional walkers driven by a length-switching engine. The model reproduces the experimental data of the walker, and identifies its performance-limiting factors. The model also captures features common to the underlying design principle, including counterintuitive performance-construction relations that are explained by detailed balance, entropy production, and bias cancellation. While indicating a low directional fidelity for the present walker, the model suggests the possibility of improving the fidelity above 90% by a more powerful engine, which may be an improved version of the present engine or an entirely new engine motif, thanks to the flexible design principle. The model is readily adaptable to aid these experimental developments towards high-performance molecular walkers.

Department of Physics' Involvement of the Impact Testing Project of the High Speed Civil Transport Program (HSCT)

NASA Technical Reports Server (NTRS)

VonMeerwall, Ernst D.

1994-01-01

The project involved the impact testing of a kevlar-like woven polymer material, PBO. The purpose was to determine whether this material showed any promise as a lightweight replacement material for jet engine fan containment. The currently used metal fan containment designs carry a high drag penalty due to their weight. Projectiles were fired at samples of PBO by means of a 0.5 inch diameter Helium powered gun. The Initial plan was to encase the samples inside a purpose-built steel "hot box" for heating and ricochet containment. The research associate's responsibility was to develop the data acquisition programs and techniques necessary to determine accurately the impacting projectile's velocity. Beyond this, the Research Associate's duties include any physical computations, experimental design, and data analysis necessary.

Parent Involvement Intervention in Developing Weight Management Skills for both Parents and Overweight/Obese Children.

PubMed

Kim, Hee Soon; Park, Jiyoung; Park, Kye-Yeong; Lee, Myung-Nam; Ham, Ok Kyung

2016-03-01

The purpose of the study was to evaluate a parent involvement intervention for childhood obesity intended to increase parents' skills in managing children's weight-related behavior and to improve child-parent relationships. Many studies reported on parental influence on childhood obesity, emphasizing parent involvement in prevention and management of childhood obesity. A randomized controlled trial was conducted. Forty-two parents of overweight/obese children were recruited from four cities and randomized to the experimental group or control group. The parental intervention was provided only to parents in the experimental group and consisted of weekly newsletters and text messages for a period of 5 weeks. Exercise classes and nutrition education were provided to all children. Lifestyle Behaviour Checklist and the Child-Parent Relationship Scale (CPRS) were used for measurement of parent outcome. For the child outcome, dietary self-efficacy, exercise frequency, and body mass index were measured. A mixed-design analysis of variance was performed with city location entered as a random effect. After the intervention, CPRS of parents and dietary self-efficacy of children showed an increase in the experimental group (p < .05). Intervention effects differed significantly according to the city location regarding the control efficacy of parents and dietary self-efficacy of children (p < .05). The results support the effectiveness of the parent involvement intervention in promoting child-parent relationship and dietary self-efficacy of children. However, a 5-week parent involvement intervention was not sufficient to produce significant changes in children's body mass index. Further research is needed to investigate effects of parent involvement intervention with long-term evaluation. Copyright © 2016. Published by Elsevier B.V.

Study of optical design of three-dimensional digital ophthalmoscopes.

PubMed

Fang, Yi-Chin; Yen, Chih-Ta; Chu, Chin-Hsien

2015-10-01

This study primarily involves using optical zoom structures to design a three-dimensional (3D) human-eye optical sensory system with infrared and visible light. According to experimental data on two-dimensional (2D) and 3D images, human-eye recognition of 3D images is substantially higher (approximately 13.182%) than that of 2D images. Thus, 3D images are more effective than 2D images when they are used at work or in high-recognition devices. In the optical system design, infrared and visible light wavebands were incorporated as light sources to perform simulations. The results can be used to facilitate the design of optical systems suitable for 3D digital ophthalmoscopes.

Ego involvement increases doping likelihood.

PubMed

Ring, Christopher; Kavussanu, Maria

2018-08-01

Achievement goal theory provides a framework to help understand how individuals behave in achievement contexts, such as sport. Evidence concerning the role of motivation in the decision to use banned performance enhancing substances (i.e., doping) is equivocal on this issue. The extant literature shows that dispositional goal orientation has been weakly and inconsistently associated with doping intention and use. It is possible that goal involvement, which describes the situational motivational state, is a stronger determinant of doping intention. Accordingly, the current study used an experimental design to examine the effects of goal involvement, manipulated using direct instructions and reflective writing, on doping likelihood in hypothetical situations in college athletes. The ego-involving goal increased doping likelihood compared to no goal and a task-involving goal. The present findings provide the first evidence that ego involvement can sway the decision to use doping to improve athletic performance.

An Experimental Test of the Roles of Audience Involvement and Message Frame in Shaping Public Reactions to Celebrity Illness Disclosures.

PubMed

Myrick, Jessica Gall

2018-04-13

Much research has investigated what happens when celebrities disclose an illness (via media) to the public. While audience involvement (i.e., identification and parasocial relationships) is often the proposed mechanism linking illness disclosures with audience behavior change, survey designs have prevented researchers from understanding if audience involvement prior to the illness disclosure actually predicts post-disclosure emotions, cognitions, and behaviors. Rooted in previous work on audience involvement as well as the Extended Parallel Process Model, the present study uses a national online experiment (N = 1,068) to test how pre-disclosure audience involvement may initiate post-disclosure effects for the message context of skin cancer. The data demonstrate that pre-disclosure audience involvement as well as the celebrity's framing of the disclosure can shape emotional responses (i.e., fear and hope), and that cognitive perceptions of the illness itself also influence behavioral intentions.

Acoustic metamaterials with synergetic coupling

NASA Astrophysics Data System (ADS)

Ma, Fuyin; Huang, Meng; Wu, Jiu Hui

2017-12-01

In this paper, we propose a general design concept for acoustic metamaterials that introduces a ubiquitous synergetic behavior into the design procedure, in which the structure of the design is driven by its functional requirements. Since the physical properties of the widely used, resonant-type metamaterials are mainly determined by the eigenmodes of the structure, we first introduce the design concept through the modal displacement distributions on two typical plate-type structures. Next, by employing broadband sound attenuations that involve both the insulation and absorption as the typical targets, two synergetic coupling behaviors are systematically revealed among the dense resonant modes and multi-cell. Furthermore, through plate-type multiple-cell structures assembled from nine oscillators, the design is shown to realize strong broadband attenuations with either the average sound transmission loss (STL) below 2000 Hz higher than 40 dB or the absorption approximately 0.99 in the range of 400-700 Hz wherein the average absorption below 800 Hz remains higher than 0.8. Finally, two multi-cell plate-type samples are fabricated and then used experimentally to measure the STLs in support of the proposed synergetic coupling design method. Both the computational and experimental results demonstrate that the proposed synergetic design concept could effectively initiate a design for metamaterials that offer a new degree of freedom for broadband sound attenuations.

Effects of a Target-Task Problem-Solving Model on Senior Secondary School Students' Performance in Physics

ERIC Educational Resources Information Center

Olaniyan, A. O.; Omosewo, E. O.

2015-01-01

The study investigated the Effects of a Target-Task Problem-Solving Model on Senior Secondary School Students' Performance in Physics. The research design was a quasi-experimental, non-randomized, non-equivalent pretest, post-test using a control group. The study was conducted in two schools purposively selected and involved a total of 120 Senior…

The Effect of a Suggested Multisensory Phonics Program on Developing Kindergarten Pre-Service Teachers' EFL Reading Accuracy and Phonemic Awareness

ERIC Educational Resources Information Center

Ghoneim, Nahed Mohammed Mahmoud; Elghotmy, Heba Elsayed Abdelsalam

2015-01-01

The current study investigates the effect of a suggested multisensory phonics program on developing kindergarten pre-service teachers' EFL reading accuracy and phonemic awareness. A total of 40 fourth year kindergarten pre-service teachers, Faculty of Education, participated in the study that involved one group experimental design. Pre-post tests…

Aeropropulsion 1987. Session 2: Aeropropulsion Structures Research

NASA Technical Reports Server (NTRS)

1987-01-01

Aeropropulsion systems present unique problems to the structural engineer. The extremes in operating temperatures, rotational effects, and behaviors of advanced material systems combine into complexities that require advances in many scientific disciplines involved in structural analysis and design procedures. This session provides an overview of the complexities of aeropropulsion structures and the theoretical, computational, and experimental research conducted to achieve the needed advances.

Blending Physical and Virtual Manipulatives: An Effort to Improve Students' Conceptual Understanding through Science Laboratory Experimentation

ERIC Educational Resources Information Center

Olympiou, Georgios; Zacharia, Zacharias C.

2012-01-01

This study aimed to investigate the effect of experimenting with physical manipulatives (PM), virtual manipulatives (VM), and a blended combination of PM and VM on undergraduate students' understanding of concepts in the domain of "Light and Color." A pre-post comparison study design was used for the purposes of this study that involved 70…

Gender Differences in Mathematics Achievement and Retention Scores: A Case of Problem-Based Learning Method

ERIC Educational Resources Information Center

Ajai, John T.; Imoko, Benjamin I.

2015-01-01

This study was undertaken to assess gender differences in mathematics achievement and retention by using Problem-Based Learning (PBL). The design of the study was pre-posttest quasi-experimental. Four hundred and twenty eight senior secondary one (SS I) students using multistage sampling from ten grant-aided and government schools were involved in…

Video Interaction Guidance in Collaborative Group Work: Impact on Primary School Pupils' Self-Esteem and Behaviours

ERIC Educational Resources Information Center

Musset, Matthew; Topping, Keith

2017-01-01

Video interaction guidance (VIG) is an increasingly recognised evidence-based intervention. VIG was used to enhance pupil responses during a group work programme. Fifteen primary-aged classes across a range of socio-economic status received regular group work over a year. A mixed methods repeated measures design involved nine experimental classes…

The Effect of Combining Analogy-Based Simulation and Laboratory Activities on Turkish Elementary School Students' Understanding of Simple Electric Circuits

ERIC Educational Resources Information Center

Unlu, Zeynep Koyunlu; Dokme, Ibilge

2011-01-01

The purpose of this study was to investigate whether the combination of both analogy-based simulation and laboratory activities as a teaching tool was more effective than utilizing them separately in teaching the concepts of simple electricity. The quasi-experimental design that involved 66 seventh grade students from urban Turkish elementary…

Effectiveness of Blended Learning and Elearning Modes of Instruction on the Performance of Undergraduates in Kwara State, Nigeria

ERIC Educational Resources Information Center

Gambari, Amosa Isiaka; Shittu, Ahmed Tajudeen; Ogunlade, O. Olufunmilola; Osunlade, Olourotimi Rufus

2017-01-01

This study investigated the effectiveness of blended learning and E-learning modes of instruction on the performance of undergraduates in Kwara State, Nigeria. It also determined if the student performance would vary with gender. Quasi experimental that employs pretest, posttest, control group design was adopted for this study. This involves three…

The Relationship between Active Hand and Ear Advantage in the Native and Foreign Language

ERIC Educational Resources Information Center

Mildner, V.; Stankovic, D.; Petkovic, M.

2005-01-01

In an experimental design involving two auditorily presented competing commands (one to each ear), 144 right-handed subjects (72 male and 72 female) were asked to provide motor responses. Half of each group of subjects was responding with their right hand and the other half with the left. The test was applied in the subjects' native language…

Building Commitment: An Examination of Learning Climate Congruence and the Affective Commitment of Academics in an Australian University

ERIC Educational Resources Information Center

Southcombe, Amie; Fulop, Liz; Carter, Geoff; Cavanagh, Jillian

2015-01-01

The purpose of this study is to explore the relationship between learning climate congruence and the affective commitment of university academics. The strategy of inquiry for this research is quantitative, involving a non-experimental design for the survey research. A non-probability sample of 900 academics from a large Australian university was…

The Effects of Using Concept Mapping for Improving Advanced Level Biology Students' Lower- and Higher-Order Cognitive Skills

ERIC Educational Resources Information Center

Bramwell-Lalor, Sharon; Rainford, Marcia

2014-01-01

This paper reports on teachers' use of concept mapping as an alternative assessment strategy in advanced level biology classes and its effects on students' cognitive skills on selected biology concepts. Using a mixed methods approach, the study employed a pre-test/post-test quasi-experimental design involving 156 students and 8 teachers from…

Computer-Mediated Input, Output and Feedback in the Development of L2 Word Recognition from Speech

ERIC Educational Resources Information Center

Matthews, Joshua; Cheng, Junyu; O'Toole, John Mitchell

2015-01-01

This paper reports on the impact of computer-mediated input, output and feedback on the development of second language (L2) word recognition from speech (WRS). A quasi-experimental pre-test/treatment/post-test research design was used involving three intact tertiary level English as a Second Language (ESL) classes. Classes were either assigned to…

Student Teachers' Team Teaching: How Do Learners in the Classroom Experience Team-Taught Lessons by Student Teachers?

ERIC Educational Resources Information Center

Baeten, Marlies; Simons, Mathea

2016-01-01

This study focuses on student teachers' team teaching. Two team teaching models (sequential and parallel teaching) were applied by 14 student teachers in a quasi-experimental design. When implementing new teaching models, it is important to take into account the perspectives of all actors involved. Although learners are key actors in the teaching…

Synthesis, structure characterization and catalytic activity of nickel tungstate nanoparticles

NASA Astrophysics Data System (ADS)

Pourmortazavi, Seied Mahdi; Rahimi-Nasrabadi, Mehdi; Khalilian-Shalamzari, Morteza; Zahedi, Mir Mahdi; Hajimirsadeghi, Seiedeh Somayyeh; Omrani, Ismail

2012-12-01

Taguchi robust design was applied to optimize experimental parameters for controllable, simple and fast synthesis of nickel tungstate nanoparticles. NiWO4 nanoparticles were synthesized by precipitation reaction involving addition of nickel ion solution to the tungstate aqueous reagent and then formation of nickel tungstate nucleolus which are insoluble in aqueous media. Effects of various parameters such as nickel and tungstate concentrations, flow rate of reagent addition and reactor temperature on diameter of synthesized nickel tungstate nanoparticles were investigated experimentally by the aid of orthogonal array design. The results for analysis of variance (ANOVA) showed that particle size of nickel tungstate can be effectively tuned by controlling significant variables involving nickel and tungstate concentrations and flow rate; while, temperature of the reactor has a no considerable effect on the size of NiWO4 particles. The ANOVA results proposed the optimum conditions for synthesis of nickel tungstate nanoparticles via this technique. Also, under optimum condition nanoparticles of NiWO4 were prepared and their structure and chemical composition were characterized by means of EDAX, XRD, SEM, FT-IR spectroscopy, UV-vis spectroscopy, and photoluminescence. Finally, catalytic activity of the nanoparticles in a cycloaddition reaction was examined.

Computational Design of Functionalized Metal–Organic Framework Nodes for Catalysis

PubMed Central

2017-01-01

Recent progress in the synthesis and characterization of metal–organic frameworks (MOFs) has opened the door to an increasing number of possible catalytic applications. The great versatility of MOFs creates a large chemical space, whose thorough experimental examination becomes practically impossible. Therefore, computational modeling is a key tool to support, rationalize, and guide experimental efforts. In this outlook we survey the main methodologies employed to model MOFs for catalysis, and we review selected recent studies on the functionalization of their nodes. We pay special attention to catalytic applications involving natural gas conversion. PMID:29392172

Applications of asymptotic confidence intervals with continuity corrections for asymmetric comparisons in noninferiority trials.

PubMed

Soulakova, Julia N; Bright, Brianna C

2013-01-01

A large-sample problem of illustrating noninferiority of an experimental treatment over a referent treatment for binary outcomes is considered. The methods of illustrating noninferiority involve constructing the lower two-sided confidence bound for the difference between binomial proportions corresponding to the experimental and referent treatments and comparing it with the negative value of the noninferiority margin. The three considered methods, Anbar, Falk-Koch, and Reduced Falk-Koch, handle the comparison in an asymmetric way, that is, only the referent proportion out of the two, experimental and referent, is directly involved in the expression for the variance of the difference between two sample proportions. Five continuity corrections (including zero) are considered with respect to each approach. The key properties of the corresponding methods are evaluated via simulations. First, the uncorrected two-sided confidence intervals can, potentially, have smaller coverage probability than the nominal level even for moderately large sample sizes, for example, 150 per group. Next, the 15 testing methods are discussed in terms of their Type I error rate and power. In the settings with a relatively small referent proportion (about 0.4 or smaller), the Anbar approach with Yates' continuity correction is recommended for balanced designs and the Falk-Koch method with Yates' correction is recommended for unbalanced designs. For relatively moderate (about 0.6) and large (about 0.8 or greater) referent proportion, the uncorrected Reduced Falk-Koch method is recommended, although in this case, all methods tend to be over-conservative. These results are expected to be used in the design stage of a noninferiority study when asymmetric comparisons are envisioned. Copyright © 2013 John Wiley & Sons, Ltd.

Flume experimentation and simulation of bedrock channel processes

NASA Astrophysics Data System (ADS)

Thompson, Douglas; Wohl, Ellen

Flume experiments can provide cost effective, physically manageable miniature representations of complex bedrock channels. The inherent change in scale in such experiments requires a corresponding change in the scale of the forces represented in the flume system. Three modeling approaches have been developed that either ignore the scaling effects, utilize the change in scaled forces, or assume similarity of process between scales. An understanding of the nonlinear influence of a change in scale on all the forces involved is important to correctly analyze model results. Similarly, proper design and operation of flume experiments requires knowledge of the fundamental components of flume systems. Entrance and exit regions of the flume are used to provide good experimental conditions in the measurement region of the flume where data are collected. To insure reproducibility, large-scale turbulence must be removed in the head of the flume and velocity profiles must become fully developed in the entrance region. Water-surface slope and flow acceleration effects from downstream water-depth control must also be isolated in the exit region. Statistical design and development of representative channel substrate also influence model results in these systems. With proper experimental design, flumes may be used to investigate bedrock channel hydraulics, sediment-transport relations, and morphologic evolution. In particular, researchers have successfully used flume experiments to demonstrate the importance of turbulence and substrate characteristics in bedrock channel evolution. Turbulence often operates in a self perpetuating fashion, can erode bedrock walls with clear water and increase the mobility of sediment particles. Bedrock substrate influences channel evolution by offering varying resistance to erosion, controlling the location or type of incision and modifying the local influence of turbulence. An increased usage of scaled flume models may help to clarify the remaining uncertainties involving turbulence, channel substrate and bedrock channel evolution.

Assess II - A simulated mission of Spacelab

NASA Technical Reports Server (NTRS)

Wegmann, H. M.; Hermann, R.; Wingett, C. M.; De Muizon, M.; Rouan, D.; Lena, P.; Wijnbergen, J.; Olthof, H.; Michel, K. W.; Werner, CH.

1978-01-01

For Assess II, the Spacelab mission simulation conducted in mid-1977, four payload specialists aboard a Convair 990 research aircraft performed six American and six European experiments during nine research flights each of six hours duration in order to evaluate the compatibility of training and experimental design. Mission organization and some initial data from the European experiments are reported. The experiments, conducted over the western U.S., involved infrared astronomy, solar brightness temperature, lidar, airglow TV, and a medical experiment for which physiological parameters were monitored. Conclusions concerning general principles of experiment design are discussed.

Experimental Results from Railgun Firings Involving Magnetic Flux Probes.

DTIC Science & Technology

1986-12-01

record is given as 6.6 x 102 As. A time of 6.6 x 102 As from shot -start falls in the region of noise past the second minimum in Figure 2. Thus the minima...capacitor bank occurred about 200 ps after shot -start. The duration of a firing in the MRAP series was approximately 750 us. The magnetic probes used...designated by a Ŗ" or a ŗ". The transverse probe is designated as MCT in Figure 1. Pieces of aluminium foil weighing about 0.012 g were used to generate

Optimal decentralized feedback control for a truss structure

NASA Technical Reports Server (NTRS)

Cagle, A.; Ozguner, U.

1989-01-01

One approach to the decentralized control of large flexible space structures involves the design of controllers for the substructures of large systems and their subsequent application to the entire coupled system. This approach is presently developed for the case of active vibration damping on an experimental large struss structure. The isolated boundary loading method is used to define component models by FEM; component controllers are designed using an interlocking control concept which minimizes the motion of the boundary nodes, thereby reducing the exchange of mechanical disturbances among components.

Flutter suppression digital control law design and testing for the AFW wind tunnel model

NASA Technical Reports Server (NTRS)

Mukhopadhyay, Vivek

1994-01-01

The design of a control law for simultaneously suppressing the symmetric and antisymmetric flutter modes of a sting mounted fixed-in-roll aeroelastic wind-tunnel model is described. The flutter suppression control law was designed using linear quadratic Gaussian theory, and it also involved control law order reduction, a gain root-locus study, and use of previous experimental results. A 23 percent increase in the open-loop flutter dynamic pressure was demonstrated during the wind-tunnel test. Rapid roll maneuvers at 11 percent above the symmetric flutter boundary were also performed when the model was in a free-to-roll configuration.

Flutter suppression digital control law design and testing for the AFW wind tunnel model

NASA Technical Reports Server (NTRS)

Mukhopadhyay, Vivek

1992-01-01

Design of a control law for simultaneously suppressing the symmetric and antisymmetric flutter modes of a sting mounted fixed-in-roll aeroelastic wind tunnel model is described. The flutter suppression control law was designed using linear quadratic Gaussian theory, and involved control law order reduction, a gain root-locus study and use of previous experimental results. A 23 percent increase in the open-loop flutter dynamic pressure was demonstrated during the wind tunnel test. Rapid roll maneuvers at 11 percent above the symmetric flutter boundary were also performed when the model was in a free-to-roll configuration.

Flutter suppression digital control law design and testing for the AFW wind-tunnel model

NASA Technical Reports Server (NTRS)

Mukhopadhyay, Vivek

1992-01-01

Design of a control law for simultaneously suppressing the symmetric and antisymmetric flutter modes of a string mounted fixed-in-roll aeroelastic wind tunnel model is described. The flutter suppression control law was designed using linear quadratic Gaussian theory and involved control law order reduction, a gain root-locus study, and the use of previous experimental results. A 23 percent increase in open-loop flutter dynamic pressure was demonstrated during the wind tunnel test. Rapid roll maneuvers at 11 percent above the symmetric flutter boundary were also performed when the model was in a free-to-roll configuration.

Design, Kinematic Optimization, and Evaluation of a Teleoperated System for Middle Ear Microsurgery

PubMed Central

Miroir, Mathieu; Nguyen, Yann; Szewczyk, Jérôme; Sterkers, Olivier; Bozorg Grayeli, Alexis

2012-01-01

Middle ear surgery involves the smallest and the most fragile bones of the human body. Since microsurgical gestures and a submillimetric precision are required in these procedures, the outcome can be potentially improved by robotic assistance. Today, there is no commercially available device in this field. Here, we describe a method to design a teleoperated assistance robotic system dedicated to the middle ear surgery. Determination of design specifications, the kinematic structure, and its optimization are detailed. The robot-surgeon interface and the command modes are provided. Finally, the system is evaluated by realistic tasks in experimental dedicated settings and in human temporal bone specimens. PMID:22927789

Experimental confirmation of a PDE-based approach to design of feedback controls

NASA Technical Reports Server (NTRS)

Banks, H. T.; Smith, Ralph C.; Brown, D. E.; Silcox, R. J.; Metcalf, Vern L.

1995-01-01

Issues regarding the experimental implementation of partial differential equation based controllers are discussed in this work. While the motivating application involves the reduction of vibration levels for a circular plate through excitation of surface-mounted piezoceramic patches, the general techniques described here will extend to a variety of applications. The initial step is the development of a PDE model which accurately captures the physics of the underlying process. This model is then discretized to yield a vector-valued initial value problem. Optimal control theory is used to determine continuous-time voltages to the patches, and the approximations needed to facilitate discrete time implementation are addressed. Finally, experimental results demonstrating the control of both transient and steady state vibrations through these techniques are presented.

A statistical approach to optimizing concrete mixture design.

PubMed

Ahmad, Shamsad; Alghamdi, Saeid A

2014-01-01

A step-by-step statistical approach is proposed to obtain optimum proportioning of concrete mixtures using the data obtained through a statistically planned experimental program. The utility of the proposed approach for optimizing the design of concrete mixture is illustrated considering a typical case in which trial mixtures were considered according to a full factorial experiment design involving three factors and their three levels (3(3)). A total of 27 concrete mixtures with three replicates (81 specimens) were considered by varying the levels of key factors affecting compressive strength of concrete, namely, water/cementitious materials ratio (0.38, 0.43, and 0.48), cementitious materials content (350, 375, and 400 kg/m(3)), and fine/total aggregate ratio (0.35, 0.40, and 0.45). The experimental data were utilized to carry out analysis of variance (ANOVA) and to develop a polynomial regression model for compressive strength in terms of the three design factors considered in this study. The developed statistical model was used to show how optimization of concrete mixtures can be carried out with different possible options.

A Statistical Approach to Optimizing Concrete Mixture Design

PubMed Central

Alghamdi, Saeid A.

2014-01-01

A step-by-step statistical approach is proposed to obtain optimum proportioning of concrete mixtures using the data obtained through a statistically planned experimental program. The utility of the proposed approach for optimizing the design of concrete mixture is illustrated considering a typical case in which trial mixtures were considered according to a full factorial experiment design involving three factors and their three levels (33). A total of 27 concrete mixtures with three replicates (81 specimens) were considered by varying the levels of key factors affecting compressive strength of concrete, namely, water/cementitious materials ratio (0.38, 0.43, and 0.48), cementitious materials content (350, 375, and 400 kg/m3), and fine/total aggregate ratio (0.35, 0.40, and 0.45). The experimental data were utilized to carry out analysis of variance (ANOVA) and to develop a polynomial regression model for compressive strength in terms of the three design factors considered in this study. The developed statistical model was used to show how optimization of concrete mixtures can be carried out with different possible options. PMID:24688405

The National Spallation Neutron Source (NSNS) Project

NASA Astrophysics Data System (ADS)

Appleton, Bill R.

1997-05-01

The need and justification for new sources and instrumentation in neutron science have been firmly established by numerous assessments since the early 1970s by the scientific community and the Department of Energy (DOE). In their 1996 budget, the DOE Office of Energy Research asked ORNL to lead the R&D and conceptual design effort for a next-generation spallation neutron source to be used for neutron scattering. To accomplish this, the NSNS collaboration involving five national laboratories (ANL, BNL, LANL, LBNL, and ORNL) has been formed. The NSNS reference design is for a 1-GeV linac and accumulator ring that delivers 1-MW proton beams in microsend pulses to a mercuty target; neutrons are produced by the spallation reaction, moderated, and guided into an experimental hall for neutron scattering. The design includes the necessary flexibility to upgrade the source in stages to significantly higher powers in the future and to expand the experimental capabilities. This talk will describe the origins at NSNS, the current funding status, progress on the technical design, user community input and the intended uses, and future prospects.

Ephus: Multipurpose Data Acquisition Software for Neuroscience Experiments

PubMed Central

Suter, Benjamin A.; O'Connor, Timothy; Iyer, Vijay; Petreanu, Leopoldo T.; Hooks, Bryan M.; Kiritani, Taro; Svoboda, Karel; Shepherd, Gordon M. G.

2010-01-01

Physiological measurements in neuroscience experiments often involve complex stimulus paradigms and multiple data channels. Ephus (http://www.ephus.org) is an open-source software package designed for general-purpose data acquisition and instrument control. Ephus operates as a collection of modular programs, including an ephys program for standard whole-cell recording with single or multiple electrodes in typical electrophysiological experiments, and a mapper program for synaptic circuit mapping experiments involving laser scanning photostimulation based on glutamate uncaging or channelrhodopsin-2 excitation. Custom user functions allow user-extensibility at multiple levels, including on-line analysis and closed-loop experiments, where experimental parameters can be changed based on recently acquired data, such as during in vivo behavioral experiments. Ephus is compatible with a variety of data acquisition and imaging hardware. This paper describes the main features and modules of Ephus and their use in representative experimental applications. PMID:21960959

Laminar Premixed and Diffusion Flames (Ground-Based Study)

NASA Technical Reports Server (NTRS)

Dai, Z.; El-Leathy, A. M.; Lin, K.-C.; Sunderland, P. B.; Xu, F.; Faeth, G. M.; Urban, D. L. (Technical Monitor); Yuan, Z.-G. (Technical Monitor)

2000-01-01

Ground-based studies of soot processes in laminar flames proceeded in two phases, considering laminar premixed flames and laminar diffusion flames, in turn. The test arrangement for laminar premixed flames involved round flat flame burners directed vertically upward at atmospheric pressure. The test arrangement for laminar jet diffusion flames involved a round fuel port directed vertically upward with various hydrocarbon fuels burning at atmospheric pressure in air. In both cases, coflow was used to prevent flame oscillations and measurements were limited to the flame axes. The measurements were sufficient to resolve soot nucleation, growth and oxidation rates, as well as the properties of the environment needed to evaluate mechanisms of these processes. The experimental methods used were also designed to maintain capabilities for experimental methods used in corresponding space-based experiments. This section of the report will be limited to consideration of flame structure for both premixed and diffusion flames.

Experimental Measurements of Heat Transfer through a Lunar Regolith Simulant in a Vibro-Fluidized Reactor Oven

NASA Technical Reports Server (NTRS)

Nayagam, Vedha; Berger, Gordon M.; Sacksteder, Kurt R.; Paz, Aaron

2012-01-01

Extraction of mission consumable resources such as water and oxygen from the planetary environment provides valuable reduction in launch-mass and potentially extends the mission duration. Processing of lunar regolith for resource extraction necessarily involves heating and chemical reaction of solid material with processing gases. Vibrofluidization is known to produce effective mixing and control of flow within granular media. In this study we present experimental results for vibrofluidized heat transfer in lunar regolith simulants (JSC-1 and JSC-1A) heated up to 900 C. The results show that the simulant bed height has a significant influence on the vibration induced flow field and heat transfer rates. A taller bed height leads to a two-cell circulation pattern whereas a single-cell circulation was observed for a shorter height. Lessons learned from these test results should provide insight into efficient design of future robotic missions involving In-Situ Resource Utilization.

Brainlab: A Python Toolkit to Aid in the Design, Simulation, and Analysis of Spiking Neural Networks with the NeoCortical Simulator.

PubMed

Drewes, Rich; Zou, Quan; Goodman, Philip H

2009-01-01

Neuroscience modeling experiments often involve multiple complex neural network and cell model variants, complex input stimuli and input protocols, followed by complex data analysis. Coordinating all this complexity becomes a central difficulty for the experimenter. The Python programming language, along with its extensive library packages, has emerged as a leading "glue" tool for managing all sorts of complex programmatic tasks. This paper describes a toolkit called Brainlab, written in Python, that leverages Python's strengths for the task of managing the general complexity of neuroscience modeling experiments. Brainlab was also designed to overcome the major difficulties of working with the NCS (NeoCortical Simulator) environment in particular. Brainlab is an integrated model-building, experimentation, and data analysis environment for the powerful parallel spiking neural network simulator system NCS.

Brainlab: A Python Toolkit to Aid in the Design, Simulation, and Analysis of Spiking Neural Networks with the NeoCortical Simulator

PubMed Central

Drewes, Rich; Zou, Quan; Goodman, Philip H.

2008-01-01

Neuroscience modeling experiments often involve multiple complex neural network and cell model variants, complex input stimuli and input protocols, followed by complex data analysis. Coordinating all this complexity becomes a central difficulty for the experimenter. The Python programming language, along with its extensive library packages, has emerged as a leading “glue” tool for managing all sorts of complex programmatic tasks. This paper describes a toolkit called Brainlab, written in Python, that leverages Python's strengths for the task of managing the general complexity of neuroscience modeling experiments. Brainlab was also designed to overcome the major difficulties of working with the NCS (NeoCortical Simulator) environment in particular. Brainlab is an integrated model-building, experimentation, and data analysis environment for the powerful parallel spiking neural network simulator system NCS. PMID:19506707

Design and Performance Analysis of an Intrinsically Safe Ultrasonic Ranging Sensor

PubMed Central

Zhang, Hongjuan; Wang, Yu; Zhang, Xu; Wang, Dong; Jin, Baoquan

2016-01-01

In flammable or explosive environments, an ultrasonic sensor for distance measurement poses an important engineering safety challenge, because the driving circuit uses an intermediate frequency transformer as an impedance transformation element, in which the produced heat or spark is available for ignition. In this paper, an intrinsically safe ultrasonic ranging sensor is designed and implemented. The waterproof piezoelectric transducer with integrated transceiver is chosen as an energy transducing element. Then a novel transducer driving circuit is designed based on an impedance matching method considering safety spark parameters to replace an intermediate frequency transformer. Then, an energy limiting circuit is developed to achieve dual levels of over-voltage and over-current protection. The detail calculation and evaluation are executed and the electrical characteristics are analyzed to verify the intrinsic safety of the driving circuit. Finally, an experimental platform of the ultrasonic ranging sensor system is constructed, which involves short-circuit protection. Experimental results show that the proposed ultrasonic ranging sensor is excellent in both ranging performance and intrinsic safety. PMID:27304958

Design and Performance Analysis of an Intrinsically Safe Ultrasonic Ranging Sensor.

PubMed

Zhang, Hongjuan; Wang, Yu; Zhang, Xu; Wang, Dong; Jin, Baoquan

2016-06-13

In flammable or explosive environments, an ultrasonic sensor for distance measurement poses an important engineering safety challenge, because the driving circuit uses an intermediate frequency transformer as an impedance transformation element, in which the produced heat or spark is available for ignition. In this paper, an intrinsically safe ultrasonic ranging sensor is designed and implemented. The waterproof piezoelectric transducer with integrated transceiver is chosen as an energy transducing element. Then a novel transducer driving circuit is designed based on an impedance matching method considering safety spark parameters to replace an intermediate frequency transformer. Then, an energy limiting circuit is developed to achieve dual levels of over-voltage and over-current protection. The detail calculation and evaluation are executed and the electrical characteristics are analyzed to verify the intrinsic safety of the driving circuit. Finally, an experimental platform of the ultrasonic ranging sensor system is constructed, which involves short-circuit protection. Experimental results show that the proposed ultrasonic ranging sensor is excellent in both ranging performance and intrinsic safety.

Design and experimental verification for optical module of optical vector-matrix multiplier.

PubMed

Zhu, Weiwei; Zhang, Lei; Lu, Yangyang; Zhou, Ping; Yang, Lin

2013-06-20

Optical computing is a new method to implement signal processing functions. The multiplication between a vector and a matrix is an important arithmetic algorithm in the signal processing domain. The optical vector-matrix multiplier (OVMM) is an optoelectronic system to carry out this operation, which consists of an electronic module and an optical module. In this paper, we propose an optical module for OVMM. To eliminate the cross talk and make full use of the optical elements, an elaborately designed structure that involves spherical lenses and cylindrical lenses is utilized in this optical system. The optical design software package ZEMAX is used to optimize the parameters and simulate the whole system. Finally, experimental data is obtained through experiments to evaluate the overall performance of the system. The results of both simulation and experiment indicate that the system constructed can implement the multiplication between a matrix with dimensions of 16 by 16 and a vector with a dimension of 16 successfully.

Corrosion Protection Properties of PPy-ND Composite Coating: Sonoelectrochemical Synthesis and Design of Experiment

NASA Astrophysics Data System (ADS)

Ashassi-Sorkhabi, H.; Bagheri, R.; Rezaei-Moghadam, B.

2016-02-01

In this research, the nanocomposite coatings comprising the polypyrrole-nanodiamond, PPy-ND, on St-12 steel electrodes were electro-synthesized using in situ polymerization process under ultrasonic irradiation. The corrosion protection performance and morphology characterization of prepared coatings were investigated by electrochemical methods and scanning electron microscopy, SEM, respectively. Also, the experimental design was employed to determine the best values considering the effective parameters such as the concentration of nanoparticles, the applied current density and synthesis time to achieve the most protective films. A response surface methodology, RSM, involving a central composite design, CCD, was applied to the modeling and optimization of the PPy-ND nanocomposite deposition. Pareto graphic analysis of the parameters indicated that the applied current density and some of the interactions were effective on the response. The electrochemical results proved that the embedment of diamond nanoparticle, DNP, improves the corrosion resistance of PPy coatings significantly. Therefore, desirable correlation exists between predicted data and experimental results.

Discharge Chamber Primary Electron Modeling Activities in Three-Dimensions

NASA Technical Reports Server (NTRS)

Steuber, Thomas J.

2004-01-01

Designing discharge chambers for ion thrusters involves many geometric configuration decisions. Various decisions will impact discharge chamber performance with respect to propellant utilization efficiency, ion production costs, and grid lifetime. These hardware design decisions can benefit from the assistance of computational modeling. Computational modeling for discharge chambers has been limited to two-dimensional codes that leveraged symmetry for interpretation into three-dimensional analysis. This paper presents model development activities towards a three-dimensional discharge chamber simulation to aid discharge chamber design decisions. Specifically, of the many geometric configuration decisions toward attainment of a worthy discharge chamber, this paper focuses on addressing magnetic circuit considerations with a three-dimensional discharge chamber simulation as a tool. With this tool, candidate discharge chamber magnetic circuit designs can be analyzed computationally to gain insight into factors that may influence discharge chamber performance such as: primary electron loss width in magnetic cusps, cathode tip position with respect to the low magnetic field volume, definition of a low magnetic field region, and maintenance of a low magnetic field region across the grid span. Corroborating experimental data will be obtained from mockup hardware tests. Initially, simulated candidate magnetic circuit designs will resemble previous successful thruster designs. To provide opportunity to improve beyond previous performance benchmarks, off-design modifications will be simulated and experimentally tested.

Living organ donation: the effect of message frame on an altruistic behaviour.

PubMed

McGregor, Lesley M; Ferguson, Eamonn; O'Carroll, Ronan E

2012-09-01

This experimental study investigates the impact of message frame and risk perceptions upon willingness to consider living organ donation. A 2 (gain vs. loss) by 2 (liver vs. kidney) by 2 (involved vs. not involved) between-group study was conducted. Eighty-seven participants completed a questionnaire after reading a vignette designed to invite participants to consider living kidney or liver donation. Within a gain frame scenario, willingness to donate was significantly higher when the risk of donating was lower. The results have important implications for the generalizability of framing theories and the promotion of living organ donation.

Strengthening the Role of Unmarried Fathers: Findings from the Co-Parent Court Project.

PubMed

Marczak, Mary S; Becher, Emily H; Hardman, Alisha M; Galos, Dylan L; Ruhland, Ebony

2015-12-01

While the importance of fathers in unmarried coparent families is a strong area of social and political interest, a dearth of community-based interventions exists for supporting the role of fathers in at-risk families. The Co-Parent Court (CPC) was a 3-year demonstration project evaluating the effectiveness of a collaborative intervention to support unmarried coparents establishing paternity and improving their coparenting relationships and paternal involvement in their child's life. A randomized-control experimental design was employed. The paper will explore father involvement and coparent relationship outcomes. © 2015 Family Process Institute.

Computational protein design and protein-ligand interaction studies for the improvement of organophosphorus degrading potential of Deinococcus radiodurans.

PubMed

Manoharan, Prabu; Sridhar, J

2018-05-01

The organophosphorus hydrolase enzyme is involved in the catalyzing reaction that involve hydrolysis of organophosphate toxic compounds. An enzyme from Deinococcus radiodurans reported as homologous to phosphotriesterase and show activity against organophosphate. In the past activity of this enzyme is low and efforts made to improve the activity by experimental mutation study. However only very few organophosphates tested against very few catalytic site mutations. In order to improve the catalytic power of the organophosphorus hydrolase enzyme, we carried out systematic functional hotspot based protein engineering strategy. The mutants tested against 46 know organophosphate compounds using molecular docking study. Finally, we carried out an extensive molecular docking study to predict the binding of 46 organophosphate compounds to wild-type protein and mutant organophosphorus hydrolase enzyme. At the end we are able to improve the degrading potential of organophosphorus hydrolase enzyme against organophosphate toxic compounds. This preliminary study and the outcome would be useful guide for the experimental scientist involved in the bioremediation of toxic organophosphate compounds. Copyright © 2018 Elsevier Inc. All rights reserved.

Inverse problems in complex material design: Applications to non-crystalline solids

NASA Astrophysics Data System (ADS)

Biswas, Parthapratim; Drabold, David; Elliott, Stephen

The design of complex amorphous materials is one of the fundamental problems in disordered condensed-matter science. While impressive developments of ab-initio simulation methods during the past several decades have brought tremendous success in understanding materials property from micro- to mesoscopic length scales, a major drawback is that they fail to incorporate existing knowledge of the materials in simulation methodologies. Since an essential feature of materials design is the synergy between experiment and theory, a properly developed approach to design materials should be able to exploit all available knowledge of the materials from measured experimental data. In this talk, we will address the design of complex disordered materials as an inverse problem involving experimental data and available empirical information. We show that the problem can be posed as a multi-objective non-convex optimization program, which can be addressed using a number of recently-developed bio-inspired global optimization techniques. In particular, we will discuss how a population-based stochastic search procedure can be used to determine the structure of non-crystalline solids (e.g. a-SiH, a-SiO2, amorphous graphene, and Fe and Ni clusters). The work is partially supported by NSF under Grant Nos. DMR 1507166 and 1507670.

Experimental investigation of alternative transmission functions: Quantitative evidence for the importance of nonlinear transmission dynamics in host-parasite systems.

PubMed

Orlofske, Sarah A; Flaxman, Samuel M; Joseph, Maxwell B; Fenton, Andy; Melbourne, Brett A; Johnson, Pieter T J

2018-05-01

Understanding pathogen transmission is crucial for predicting and managing disease. Nonetheless, experimental comparisons of alternative functional forms of transmission remain rare, and those experiments that are conducted are often not designed to test the full range of possible forms. To differentiate among 10 candidate transmission functions, we used a novel experimental design in which we independently varied four factors-duration of exposure, numbers of parasites, numbers of hosts and parasite density-in laboratory infection experiments. We used interactions between amphibian hosts and trematode parasites as a model system and all candidate models incorporated parasite depletion. An additional manipulation involving anaesthesia addressed the effects of host behaviour on transmission form. Across all experiments, nonlinear transmission forms involving either a power law or a negative binomial function were the best-fitting models and consistently outperformed the linear density-dependent and density-independent functions. By testing previously published data for two other host-macroparasite systems, we also found support for the same nonlinear transmission forms. Although manipulations of parasite density are common in transmission studies, the comprehensive set of variables tested in our experiments revealed that variation in density alone was least likely to differentiate among competing transmission functions. Across host-pathogen systems, nonlinear functions may often more accurately represent transmission dynamics and thus provide more realistic predictions for infection. © 2017 The Authors. Journal of Animal Ecology published by John Wiley & Sons Ltd on behalf of British Ecological Society.

Optimal bioprocess design through a gene regulatory network - growth kinetic hybrid model: Towards Replacing Monod kinetics.

PubMed

Tsipa, Argyro; Koutinas, Michalis; Usaku, Chonlatep; Mantalaris, Athanasios

2018-05-02

Currently, design and optimisation of biotechnological bioprocesses is performed either through exhaustive experimentation and/or with the use of empirical, unstructured growth kinetics models. Whereas, elaborate systems biology approaches have been recently explored, mixed-substrate utilisation is predominantly ignored despite its significance in enhancing bioprocess performance. Herein, bioprocess optimisation for an industrially-relevant bioremediation process involving a mixture of highly toxic substrates, m-xylene and toluene, was achieved through application of a novel experimental-modelling gene regulatory network - growth kinetic (GRN-GK) hybrid framework. The GRN model described the TOL and ortho-cleavage pathways in Pseudomonas putida mt-2 and captured the transcriptional kinetics expression patterns of the promoters. The GRN model informed the formulation of the growth kinetics model replacing the empirical and unstructured Monod kinetics. The GRN-GK framework's predictive capability and potential as a systematic optimal bioprocess design tool, was demonstrated by effectively predicting bioprocess performance, which was in agreement with experimental values, when compared to four commonly used models that deviated significantly from the experimental values. Significantly, a fed-batch biodegradation process was designed and optimised through the model-based control of TOL Pr promoter expression resulting in 61% and 60% enhanced pollutant removal and biomass formation, respectively, compared to the batch process. This provides strong evidence of model-based bioprocess optimisation at the gene level, rendering the GRN-GK framework as a novel and applicable approach to optimal bioprocess design. Finally, model analysis using global sensitivity analysis (GSA) suggests an alternative, systematic approach for model-driven strain modification for synthetic biology and metabolic engineering applications. Copyright © 2018. Published by Elsevier Inc.

Nonmedical influences on medical decision making: an experimental technique using videotapes, factorial design, and survey sampling.

PubMed Central

Feldman, H A; McKinlay, J B; Potter, D A; Freund, K M; Burns, R B; Moskowitz, M A; Kasten, L E

1997-01-01

OBJECTIVE: To study nonmedical influences on the doctor-patient interaction. A technique using simulated patients and "real" doctors is described. DATA SOURCES: A random sample of physicians, stratified on such characteristics as demographics, specialty, or experience, and selected from commercial and professional listings. STUDY DESIGN: A medical appointment is depicted on videotape by professional actors. The patient's presenting complaint (e.g., chest pain) allows a range of valid interpretation. Several alternative versions are taped, featuring the same script with patient-actors of different age, sex, race, or other characteristics. Fractional factorial design is used to select a balanced subset of patient characteristics, reducing costs without biasing the outcome. DATA COLLECTION: Each physician is shown one version of the videotape appointment and is asked to describe how he or she would diagnose or treat such a patient. PRINCIPAL FINDINGS: Two studies using this technique have been completed to date, one involving chest pain and dyspnea and the other involving breast cancer. The factorial design provided sufficient power, despite limited sample size, to demonstrate with statistical significance various influences of the experimental and stratification variables, including the patient's gender and age and the physician's experience. Persistent recruitment produced a high response rate, minimizing selection bias and enhancing validity. CONCLUSION: These techniques permit us to determine, with a degree of control unattainable in observational studies, whether medical decisions as described by actual physicians and drawn from a demographic or professional group of interest, are influenced by a prescribed set of nonmedical factors. PMID:9240285

An inquiry-based practical for a large, foundation-level undergraduate laboratory that enhances student understanding of basic cellular concepts and scientific experimental design.

PubMed

Bugarcic, A; Zimbardi, K; Macaranas, J; Thorn, P

2012-01-01

Student-centered education involving research experiences or inquiry have been shown to help undergraduate students understand, and become excited about, the process of scientific investigation. These benefits are particularly important for students in the early stages of their degree (Report and Kenny, http://naplesccsunysbedu/Pres/boyernsf/1998). However, embedding such experiences into the curriculum is particularly difficult when dealing with early stage students, who are in larger cohorts and often lack the background content knowledge necessary to engage with primary research literature and research level methods and equipment. We report here the design, delivery, assessment, and subsequent student learning outcomes of a 4-week practical module for 120 students at the beginning of their second year of university, which successfully engages students in designing cell culture experiments and in understanding the molecular processes and machinery involved in the basic cellular process of macropinocytosis. Copyright © 2011 Wiley Periodicals, Inc.

An Extended Case Study Methoology for Investigating Influence of Cultural, Organizational, and Automation Factors on Human-Automation Trust

NASA Technical Reports Server (NTRS)

Koltai, Kolina Sun; Ho, Nhut; Masequesmay, Gina; Niedober, David; Skoog, Mark; Johnson, Walter; Cacanindin, Artemio

2014-01-01

This paper discusses a case study that examined the influence of cultural, organizational and automation capability upon human trust in, and reliance on, automation. In particular, this paper focuses on the design and application of an extended case study methodology, and on the foundational lessons revealed by it. Experimental test pilots involved in the research and development of the US Air Forces newly developed Automatic Ground Collision Avoidance System served as the context for this examination. An eclectic, multi-pronged approach was designed to conduct this case study, and proved effective in addressing the challenges associated with the cases politically sensitive and military environment. Key results indicate that the system design was in alignment with pilot culture and organizational mission, indicating the potential for appropriate trust development in operational pilots. These include the low-vulnerabilityhigh risk nature of the pilot profession, automation transparency and suspicion, system reputation, and the setup of and communications among organizations involved in the system development.

Harmonic distortion in microwave photonic filters.

PubMed

Rius, Manuel; Mora, José; Bolea, Mario; Capmany, José

2012-04-09

We present a theoretical and experimental analysis of nonlinear microwave photonic filters. Far from the conventional condition of low modulation index commonly used to neglect high-order terms, we have analyzed the harmonic distortion involved in microwave photonic structures with periodic and non-periodic frequency responses. We show that it is possible to design microwave photonic filters with reduced harmonic distortion and high linearity even under large signal operation.

A Three-Dimensional Approach and Open Source Structure for the Design and Experimentation of Teaching-Learning Sequences: The Case of Friction

ERIC Educational Resources Information Center

Besson, Ugo; Borghi, Lidia; De Ambrosis, Anna; Mascheretti, Paolo

2010-01-01

We have developed a teaching-learning sequence (TLS) on friction based on a preliminary study involving three dimensions: an analysis of didactic research on the topic, an overview of usual approaches, and a critical analysis of the subject, considered also in its historical development. We found that mostly the usual presentations do not take…

Coqui frog populations are negatively affected by canopy opening but not detritus deposition following an experimental hurricane in a tropical rainforest

Treesearch

Paul D. Klawanski; Ben Dalton; Aaron B. Shiels

2014-01-01

Hurricanes, cyclones, and typhoons are common disturbances in many island and coastal forests. There is a lack of understanding of the importance to forest biota of the two major physical aspects that occur simultaneously during a hurricane: canopy disturbance and detritus (debris) deposition onto the ground. Using a replicated factorial design, our study involved...

Direct Teaching of Vocabulary after Listening: Is It Worth the Effort and What Method is Best?

ERIC Educational Resources Information Center

Hennebry, Mairin; Rogers, Vivienne; Macaro, Ernesto; Murphy, Victoria

2017-01-01

This paper reports a study comparing the effects of vocabulary instruction on recognition and recall through provision of either an L1 equivalent or an L2 (French) definition. Instruction was in the context of a focus-on-meaning listening activity. The study employed a quasi-experimental design, involving 262 Year 9 learners of French in seven…

What Differentiates Adolescent Problematic Drinkers from Their Peers? Results from a Cross-Sectional Study in Northern Irish School Children

ERIC Educational Resources Information Center

McKay, Michael T.; Sumnall, Harry; Goudie, Andrew J.; Field, Matt; Cole, Jon C.

2011-01-01

Aim: To investigate whether or not a range of factors were associated with problematic drinking, as assessed using the Adolescent Alcohol Involvement Scale (AAIS) in a sample of 11-16-year olds in Northern Ireland. Methods: The study used a cross-sectional experimental design. Post-primary schools in the Eastern Health Board Area of Northern…

Computer Aided Enzyme Design and Catalytic Concepts

PubMed Central

Frushicheva, Maria P.; Mills, Matthew J. L.; Schopf, Patrick; Singh, Manoj K.; Warshel, Arieh

2014-01-01

Gaining a deeper understanding of enzyme catalysis is of great practical and fundamental importance. Over the years it has become clear that despite advances made in experimental mutational studies, a quantitative understanding of enzyme catalysis will not be possible without the use of computer modeling approaches. While we believe that electrostatic preorganization is by far the most important catalytic factor, convincing the wider scientific community of this may require the demonstration of effective rational enzyme design. Here we make the point that the main current advances in enzyme design are basically advances in directed evolution and that computer aided enzyme design must involve approaches that can reproduce catalysis in well-defined test cases. Such an approach is provided by the empirical valence bond method. PMID:24814389

De Novo Computational Design of Retro-Aldol Enzymes

PubMed Central

Jiang, Lin; Althoff, Eric A.; Clemente, Fernando R.; Doyle, Lindsey; Röthlisberger, Daniela; Zanghellini, Alexandre; Gallaher, Jasmine L.; Betker, Jamie L.; Tanaka, Fujie; Barbas, Carlos F.; Hilvert, Donald; Houk, Kendall N.; Stoddard, Barry L.; Baker, David

2012-01-01

The creation of enzymes capable of catalyzing any desired chemical reaction is a grand challenge for computational protein design. Using new algorithms that rely on hashing techniques to construct active sites for multistep reactions, we designed retro-aldolases that use four different catalytic motifs to catalyze the breaking of a carbon-carbon bond in a nonnatural substrate. Of the 72 designs that were experimentally characterized, 32, spanning a range of protein folds, had detectable retro-aldolase activity. Designs that used an explicit water molecule to mediate proton shuffling were significantly more successful, with rate accelerations of up to four orders of magnitude and multiple turnovers, than those involving charged side-chain networks. The atomic accuracy of the design process was confirmed by the x-ray crystal structure of active designs embedded in two protein scaffolds, both of which were nearly superimposable on the design model. PMID:18323453

Semester-long inquiry-based molecular biology laboratory: Transcriptional regulation in yeast.

PubMed

Oelkers, Peter M

2017-03-04

A single semester molecular biology laboratory has been developed in which students design and execute a project examining transcriptional regulation in Saccharomyces cerevisiae. Three weeks of planning are allocated to developing a hypothesis through literature searches and use of bioinformatics. Common experimental plans address a cell process and how three genes that encode for proteins involved in that process are transcriptionally regulated in response to changing environmental conditions. Planning includes designing oligonucleotides to amplify the putative promoters of the three genes of interest. After the PCR, each product is cloned proximal to β-galactosidase in a yeast reporter plasmid. Techniques used include agarose electrophoresis, extraction of DNA from agarose, plasmid purification from bacteria, restriction digestion, ligation, and bacterial transformation. This promoter/reporter plasmid is then transformed into yeast. Transformed yeast are cultured in conditions prescribed in the experimental design, lysed and β-galactosidase activity is measured. The course provides an independent research experience in a group setting. Notebooks are maintained on-line with regular feedback. Projects culminate with the presentation of a poster worth 60% of the grade. Over the last three years, about 65% of students met expectations for experimental design, data acquisition, and analysis. © 2016 by The International Union of Biochemistry and Molecular Biology, 45(2):145-151, 2017. © 2016 The International Union of Biochemistry and Molecular Biology.

Computer experimental analysis of the CHP performance of a 100 kW e SOFC Field Unit by a factorial design

NASA Astrophysics Data System (ADS)

Calì, M.; Santarelli, M. G. L.; Leone, P.

Gas Turbine Technologies (GTT) and Politecnico di Torino, both located in Torino (Italy), have been involved in the design and installation of a SOFC laboratory in order to analyse the operation, in cogenerative configuration, of the CHP 100 kW e SOFC Field Unit, built by Siemens-Westinghouse Power Corporation (SWPC), which is at present (May 2005) starting its operation and which will supply electric and thermal power to the GTT factory. In order to take the better advantage from the analysis of the on-site operation, and especially to correctly design the scheduled experimental tests on the system, we developed a mathematical model and run a simulated experimental campaign, applying a rigorous statistical approach to the analysis of the results. The aim of this work is the computer experimental analysis, through a statistical methodology (2 k factorial experiments), of the CHP 100 performance. First, the mathematical model has been calibrated with the results acquired during the first CHP100 demonstration at EDB/ELSAM in Westerwoort. After, the simulated tests have been performed in the form of computer experimental session, and the measurement uncertainties have been simulated with perturbation imposed to the model independent variables. The statistical methodology used for the computer experimental analysis is the factorial design (Yates' Technique): using the ANOVA technique the effect of the main independent variables (air utilization factor U ox, fuel utilization factor U F, internal fuel and air preheating and anodic recycling flow rate) has been investigated in a rigorous manner. Analysis accounts for the effects of parameters on stack electric power, thermal recovered power, single cell voltage, cell operative temperature, consumed fuel flow and steam to carbon ratio. Each main effect and interaction effect of parameters is shown with particular attention on generated electric power and stack heat recovered.

Modelling and simulation of complex sociotechnical systems: envisioning and analysing work environments

PubMed Central

Hettinger, Lawrence J.; Kirlik, Alex; Goh, Yang Miang; Buckle, Peter

2015-01-01

Accurate comprehension and analysis of complex sociotechnical systems is a daunting task. Empirically examining, or simply envisioning the structure and behaviour of such systems challenges traditional analytic and experimental approaches as well as our everyday cognitive capabilities. Computer-based models and simulations afford potentially useful means of accomplishing sociotechnical system design and analysis objectives. From a design perspective, they can provide a basis for a common mental model among stakeholders, thereby facilitating accurate comprehension of factors impacting system performance and potential effects of system modifications. From a research perspective, models and simulations afford the means to study aspects of sociotechnical system design and operation, including the potential impact of modifications to structural and dynamic system properties, in ways not feasible with traditional experimental approaches. This paper describes issues involved in the design and use of such models and simulations and describes a proposed path forward to their development and implementation. Practitioner Summary: The size and complexity of real-world sociotechnical systems can present significant barriers to their design, comprehension and empirical analysis. This article describes the potential advantages of computer-based models and simulations for understanding factors that impact sociotechnical system design and operation, particularly with respect to process and occupational safety. PMID:25761227

Experimental study designs to improve the evaluation of road mitigation measures for wildlife.

PubMed

Rytwinski, Trina; van der Ree, Rodney; Cunnington, Glenn M; Fahrig, Lenore; Findlay, C Scott; Houlahan, Jeff; Jaeger, Jochen A G; Soanes, Kylie; van der Grift, Edgar A

2015-05-01

An experimental approach to road mitigation that maximizes inferential power is essential to ensure that mitigation is both ecologically-effective and cost-effective. Here, we set out the need for and standards of using an experimental approach to road mitigation, in order to improve knowledge of the influence of mitigation measures on wildlife populations. We point out two key areas that need to be considered when conducting mitigation experiments. First, researchers need to get involved at the earliest stage of the road or mitigation project to ensure the necessary planning and funds are available for conducting a high quality experiment. Second, experimentation will generate new knowledge about the parameters that influence mitigation effectiveness, which ultimately allows better prediction for future road mitigation projects. We identify seven key questions about mitigation structures (i.e., wildlife crossing structures and fencing) that remain largely or entirely unanswered at the population-level: (1) Does a given crossing structure work? What type and size of crossing structures should we use? (2) How many crossing structures should we build? (3) Is it more effective to install a small number of large-sized crossing structures or a large number of small-sized crossing structures? (4) How much barrier fencing is needed for a given length of road? (5) Do we need funnel fencing to lead animals to crossing structures, and how long does such fencing have to be? (6) How should we manage/manipulate the environment in the area around the crossing structures and fencing? (7) Where should we place crossing structures and barrier fencing? We provide experimental approaches to answering each of them using example Before-After-Control-Impact (BACI) study designs for two stages in the road/mitigation project where researchers may become involved: (1) at the beginning of a road/mitigation project, and (2) after the mitigation has been constructed; highlighting real case studies when available. Copyright © 2015 Elsevier Ltd. All rights reserved.

Experimental results for a hypersonic nozzle/afterbody flow field

NASA Technical Reports Server (NTRS)

Spaid, Frank W.; Keener, Earl R.; Hui, Frank C. L.

1995-01-01

This study was conducted to experimentally characterize the flow field created by the interaction of a single-expansion ramp-nozzle (SERN) flow with a hypersonic external stream. Data were obtained from a generic nozzle/afterbody model in the 3.5 Foot Hypersonic Wind Tunnel at the NASA Ames Research Center, in a cooperative experimental program involving Ames and McDonnell Douglas Aerospace. The model design and test planning were performed in close cooperation with members of the Ames computational fluid dynamics (CFD) team for the National Aerospace Plane (NASP) program. This paper presents experimental results consisting of oil-flow and shadow graph flow-visualization photographs, afterbody surface-pressure distributions, rake boundary-layer measurements, Preston-tube skin-friction measurements, and flow field surveys with five-hole and thermocouple probes. The probe data consist of impact pressure, flow direction, and total temperature profiles in the interaction flow field.

Technical, analytical and computer support

NASA Technical Reports Server (NTRS)

1972-01-01

The development of a rigorous mathematical model for the design and performance analysis of cylindrical silicon-germanium thermoelectric generators is reported that consists of two parts, a steady-state (static) and a transient (dynamic) part. The material study task involves the definition and implementation of a material study that aims to experimentally characterize the long term behavior of the thermoelectric properties of silicon-germanium alloys as a function of temperature. Analytical and experimental efforts are aimed at the determination of the sublimation characteristics of silicon germanium alloys and the study of sublimation effects on RTG performance. Studies are also performed on a variety of specific topics on thermoelectric energy conversion.

Engineering and simulation of life science Spacelab experiments

NASA Technical Reports Server (NTRS)

Bush, B.; Rummel, J.; Johnston, R. S.

1977-01-01

Approaches to the planning and realization of Spacelab life sciences experiments, which may involve as many as 16 Space Shuttle missions and 100 tests, are discussed. In particular, a Spacelab simulation program, designed to evaluate problems associated with the use of live animal specimens, the constraints imposed by zero gravity on equipment operation, training of investigators and data management, is described. The simulated facility approximates the hardware and support systems of a current European Space Agency Spacelab model. Preparations necessary for the experimental program, such as crew activity plans, payload documentation and inflight experimental procedures are developed; health problems of the crew, including human/animal microbial contamination, are also assessed.

A conceptual design study of the reusable reentry satellite

NASA Technical Reports Server (NTRS)

Swenson, Byron L.; Mascy, Alfred C.; Carter, Bruce; Cartledge, Alan; Corridan, Robert E.; Edsinger, Larry E.; Jackson, Robert W.; Keller, Robert; Murbach, Marcus S.; Wercinski, Paul F.

1988-01-01

Experimentation leading to an understanding of life processes under reduced and extremely low gravitational forces will profoundly contribute to the success of future space missions involving humans. In addition to research on gravitational biology, research on the effects of cosmic radiation and the interruption and change of circadian rhythms on life systems is also of prime importance. Research in space, however, is currently viewed by biological scientists as an arena that is essential, yet largely inaccessible to them for their experimentation. To fulfill this need, a project and spacecraft system described as the Reusuable Reentry Satellite or Lifesat has been proposed by NASA.

Measuring the impact of enhanced kinship navigator services for informal kinship caregivers using an experimental design.

PubMed

Feldman, Leonard H; Fertig, Amanda

2013-01-01

While relative care may offer significant benefits to kin children as compared to non-relative foster care, informal kinship caregivers often experience various hardships and needs without the resources of the child welfare system to aid them. They may benefit from services provided by an expanded kinship navigator program. This study, using an experimental design, adds to knowledge about the characteristics and needs of kinship caregivers and the impact of enhanced navigator services. The relative effect of this more intensive intervention was mixed. Caregivers had many of their expressed needs met. Yet, the enhanced services group did not demonstrate: an increase in perceived social support; reduction in caregiver stress; or improvement in child behavior compared to the families receiving brief, traditional navigator services. Little difference was found in post intervention involvement in the child welfare system. Further enhancements to the model are suggested.

Development of Problem-Based Learning Oriented Teaching Learning Materials to Facilitate Students’ Mastery of Concept and Critical Thinking Skill

NASA Astrophysics Data System (ADS)

Reza, M.; Ibrahim, M.; Rahayu, Y. S.

2018-01-01

This research aims to develop problem-based learning oriented teaching materials to improve students’ mastery of concept and critical thinking skill. Its procedure was divided into two phases; developmental phase and experimental phase. This developmental research used Four-D Model. However, within this research, the process of development would not involve the last stages, which is disseminate. The teaching learning materials which were developed consist of lesson plan, student handbook, student worksheet, achievement test and critical thinking skill test. The experimental phase employs a research design called one group pretest-posttest design. Results show that the validity of the teaching materials which were developed was good and revealed the enhancement of students’ activities with positive response to the teaching learning process. Furthermore, the learning materials improve the students’ mastery of concept and critical thinking skill.

Evaluation of General Classes of Reliability Estimators Often Used in Statistical Analyses of Quasi-Experimental Designs

NASA Astrophysics Data System (ADS)

Saini, K. K.; Sehgal, R. K.; Sethi, B. L.

2008-10-01

In this paper major reliability estimators are analyzed and there comparatively result are discussed. There strengths and weaknesses are evaluated in this case study. Each of the reliability estimators has certain advantages and disadvantages. Inter-rater reliability is one of the best ways to estimate reliability when your measure is an observation. However, it requires multiple raters or observers. As an alternative, you could look at the correlation of ratings of the same single observer repeated on two different occasions. Each of the reliability estimators will give a different value for reliability. In general, the test-retest and inter-rater reliability estimates will be lower in value than the parallel forms and internal consistency ones because they involve measuring at different times or with different raters. Since reliability estimates are often used in statistical analyses of quasi-experimental designs.

Evaluation of ground motion scaling methods for analysis of structural systems

USGS Publications Warehouse

O'Donnell, A. P.; Beltsar, O.A.; Kurama, Y.C.; Kalkan, E.; Taflanidis, A.A.

2011-01-01

Ground motion selection and scaling comprises undoubtedly the most important component of any seismic risk assessment study that involves time-history analysis. Ironically, this is also the single parameter with the least guidance provided in current building codes, resulting in the use of mostly subjective choices in design. The relevant research to date has been primarily on single-degree-of-freedom systems, with only a few studies using multi-degree-of-freedom systems. Furthermore, the previous research is based solely on numerical simulations with no experimental data available for the validation of the results. By contrast, the research effort described in this paper focuses on an experimental evaluation of selected ground motion scaling methods based on small-scale shake-table experiments of re-configurable linearelastic and nonlinear multi-story building frame structure models. Ultimately, the experimental results will lead to the development of guidelines and procedures to achieve reliable demand estimates from nonlinear response history analysis in seismic design. In this paper, an overview of this research effort is discussed and preliminary results based on linear-elastic dynamic response are presented. ?? ASCE 2011.

Intercomparison of Monte Carlo radiation transport codes to model TEPC response in low-energy neutron and gamma-ray fields.

PubMed

Ali, F; Waker, A J; Waller, E J

2014-10-01

Tissue-equivalent proportional counters (TEPC) can potentially be used as a portable and personal dosemeter in mixed neutron and gamma-ray fields, but what hinders this use is their typically large physical size. To formulate compact TEPC designs, the use of a Monte Carlo transport code is necessary to predict the performance of compact designs in these fields. To perform this modelling, three candidate codes were assessed: MCNPX 2.7.E, FLUKA 2011.2 and PHITS 2.24. In each code, benchmark simulations were performed involving the irradiation of a 5-in. TEPC with monoenergetic neutron fields and a 4-in. wall-less TEPC with monoenergetic gamma-ray fields. The frequency and dose mean lineal energies and dose distributions calculated from each code were compared with experimentally determined data. For the neutron benchmark simulations, PHITS produces data closest to the experimental values and for the gamma-ray benchmark simulations, FLUKA yields data closest to the experimentally determined quantities. © The Author 2013. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Design and experimental study on desulphurization process of ship exhaust

NASA Astrophysics Data System (ADS)

Han, Mingyang; Hao, Shan; Zhou, Junbo; Gao, Liping

2018-02-01

This desulfurization process involves removing sulfur oxides with seawater or alkaline aqueous solutions and then treating the effluent by aeration and pH adjustment before discharging it into the ocean. In the desulfurization system, the spray tower is the key equipment and the venturi tubes are the pretreatment device. The two stages of plates are designed to fully absorb sulfur oxides in exhaust gases. The spiral nozzles atomize and evenly spray the desulfurizers into the tower. This study experimentally investigated the effectiveness of this desulfurization process and the factors influencing it under laboratory conditions, with a diesel engine exhaust used to represent ship exhaust. The experimental results show that this process can effectively absorb the SO2 in the exhaust. When the exhaust flow rate was 25 m3/h and the desulfurizer flow rate was 4 L/min, the sulfur removal efficiency (SRE) reached 99.7%. The flow rate, alkalinity, and temperature of seawater were found to have significant effects on the SRE. Adjusting seawater flow rate (SWR) and alkalinity within certain ranges can substantially improve the SRE.

Added-purpose versus rote exercise in female nursing home residents.

PubMed

Yoder, R M; Nelson, D L; Smith, D A

1989-09-01

Seven recent experimental and quasi-experimental studies have compared the exercise of subjects instructed to pursue some added goal (often termed purposeful activity) with the exercise of subjects instructed to exercise without the suggestion of an added goal (often termed nonpurposeful activity). This article suggests a new terminology for this type of independent variable and describes an experiment within this developing tradition. An occupational form designed, through materials and instructions, to elicit a rotary arm exercise with the added purpose of stirring cookie dough was compared with an occupational form designed to elicit the rotary arm exercise with no added purpose. The subjects were 30 elderly female nursing home residents randomly assigned to the occupational forms. Results indicated that the added-purpose, occupationally embedded exercise condition elicited significantly more exercise repetitions than did the rote exercise condition (one-tailed p = .012). Exercise duration and exercise stoppages were also recorded. This study provides additional support for the traditional occupational therapy idea of embedding exercise within occupation. Suggestions are made for future research involving the experimental analysis of therapeutic occupation.

Determination of excitation profile and dielectric function spatial nonuniformity in porous silicon by using WKB approach.

PubMed

He, Wei; Yurkevich, Igor V; Canham, Leigh T; Loni, Armando; Kaplan, Andrey

2014-11-03

We develop an analytical model based on the WKB approach to evaluate the experimental results of the femtosecond pump-probe measurements of the transmittance and reflectance obtained on thin membranes of porous silicon. The model allows us to retrieve a pump-induced nonuniform complex dielectric function change along the membrane depth. We show that the model fitting to the experimental data requires a minimal number of fitting parameters while still complying with the restriction imposed by the Kramers-Kronig relation. The developed model has a broad range of applications for experimental data analysis and practical implementation in the design of devices involving a spatially nonuniform dielectric function, such as in biosensing, wave-guiding, solar energy harvesting, photonics and electro-optical devices.

Recent Progress on the VASIMR

NASA Technical Reports Server (NTRS)

ChangDiaz, Franklin R.; Squire, J. P.; Ilin, A. V.; Jacobson, V. T.; Glover, T. W.; Baity, F. W.; Carter, M. D.; Goulding, R. H.; Breizman, B. N.

1999-01-01

Experimental and theoretical studies on the Variable Specific Impulse Magnetoplasma Rocket (VASIMR) have continued through a NASA led collaborative program involving several research groups. In the experimental area, performance characterization of the VASIMR helicon plasma source has been obtained over a portion of the parameter space, with helium and hydrogen propellant. Density (10(exp 18) - 10(exp 19)/ cubic meter) and temperature (5 eV) were measured at moderate degree of ionization in two separate experimental devices. Helicon design improvement and optimization will be discussed. Experiments with the ion cyclotron resonance heating (ICRH) subsection have begun and preliminary results will be discussed. Theoretical picture and integrated numerical simulation continue to be refined to account for the main physics elements of the VASIMR, including RF absorption and particle acceleration with subsequent detachment in the magnetic nozzle.

A mobile phone based alarm system for supervising vital parameters in free moving rats.

PubMed

Kellermann, Kristine; Kreuzer, Matthias; Omerovich, Adem; Hoetzinger, Franziska; Kochs, Eberhard F; Jungwirth, Bettina

2012-02-23

Study protocols involving experimental animals often require the monitoring of different parameters not only in anesthetized, but also in free moving animals. Most animal research involves small rodents, in which continuously monitoring parameters such as temperature and heart rate is very stressful for the awake animals or simply not possible. Aim of the underlying study was to monitor heart rate, temperature and activity and to assess inflammation in the heart, lungs, liver and kidney in the early postoperative phase after experimental cardiopulmonary bypass involving 45 min of deep hypothermic circulatory arrest in rats. Besides continuous monitoring of heart rate, temperature and behavioural activity, the main focus was on avoiding uncontrolled death of an animal in the early postoperative phase in order to harvest relevant organs before autolysis would render them unsuitable for the assessment of inflammation. We therefore set up a telemetry-based system (Data Science International, DSI™) that continuously monitored the rat's temperature, heart rate and activity in their cages. The data collection using telemetry was combined with an analysis software (Microsoft excel™), a webmail application (GMX) and a text message-service. Whenever an animal's heart rate dropped below the pre-defined threshold of 150 beats per minute (bpm), a notification in the form of a text message was automatically sent to the experimenter's mobile phone. With a positive predictive value of 93.1% and a negative predictive value of 90.5%, the designed surveillance and alarm system proved a reliable and inexpensive tool to avoid uncontrolled death in order to minimize suffering and harvest relevant organs before autolysis would set in. This combination of a telemetry-based system and software tools provided us with a reliable notification system of imminent death. The system's high positive predictive value helped to avoid uncontrolled death and facilitated timely organ harvesting. Additionally we were able to markedly reduce the drop out rate of experimental animals, and therefore the total number of animals used in our study. This system can be easily adapted to different study designs and prove a helpful tool to relieve stress and more importantly help to reduce animal numbers.

Experimental and Numerical Study on Supersonic Ejectors Working with R-1234ze(E)

NASA Astrophysics Data System (ADS)

Kracik, Jan; Dvorak, Vaclav; Nguyen Van, Vu; Smierciew, Kamil

2018-06-01

These days, much effort is being put into lowering the consumption of electric energy and involving renewable energy sources. Many engineers and designers are trying to develop environment-friendly technologies worldwide. It is related to incorporating appropriate devices into such technologies. The object of this paper is to investigate these devices in connection with refrigeration systems. Ejectors can be considered such as these devices. The primary interest of this paper is to investigate the suitability of a numerical model for an ejector, which is incorporated into a refrigeration system. In the present paper, there have been investigated seven different test runs of working of the ejector with a working fluid R-1234ze(E). Some of the investigated cases seem to have a good agreement and there are no significant discrepancies between them, however, there are also cases that do not correspond to the experimental data at all. The ejector has been investigated in both on-design and off-design working modes. A comparison between the experimental and numerical data (CFD) performed by Ansys Fluent software is presented and discussed for both an ideal and a real gas model. In addition, an enhanced analytical model has been introduced for all runs of the ejector.

Small Engine Technology. Task 4: Advanced Small Turboshaft Compressor (ASTC) Performance and Range Investigation

NASA Technical Reports Server (NTRS)

Hansen, Jeff L.; Delaney, Robert A.

1997-01-01

This contact had two main objectives involving both numerical and experimental investigations of a small highly loaded two-stage axial compressor designated Advanced Small Turboshaft Compressor (ASTC) winch had a design pressure ratio goal of 5:1 at a flowrate of 10.53 lbm/s. The first objective was to conduct 3-D Navier Stokes multistage analyses of the ASTC using several different flow modelling schemes. The second main objective was to complete a numerical/experimental investigation into stall range enhancement of the ASTC. This compressor was designed wider a cooperative Space Act Agreement and all testing was completed at NASA Lewis Research Center. For the multistage analyses, four different flow model schemes were used, namely: (1) steady-state ADPAC analysis, (2) unsteady ADPAC analysis, (3) steady-state APNASA analysis, and (4) steady state OCOM3D analysis. The results of all the predictions were compared to the experimental data. The steady-state ADPAC and APNASA codes predicted similar overall performance and produced good agreement with data, however the blade row performance and flowfield details were quite different. In general, it can be concluded that the APNASA average-passage code does a better job of predicting the performance and flowfield details of the highly loaded ASTC compressor.

Study concerning the loads over driver's chests in car crashes with cars of the same or different generation

NASA Astrophysics Data System (ADS)

Ispas, N.; Năstăsoiu, M.

2016-08-01

Reducing occupant injuries for cars involves in traffic accidents is a main target of today cars designers. Known as active or passive safety, many technological solutions were developing over the time for an actual better car's occupant safety. In the real world, in traffic accidents are often involved cars from different generations with various safety historical solutions. The main aim of these papers are to quantify the influences over the car driver chest loads in cases of same or different generation of cars involved in side car crashes. Both same and different cars generations were used for the study. Other goal of the paper was the study of in time loads conformity for diver's chests from both cars involved in crash. The paper's experimental results were obtained by support of DSD, Dr. Steffan Datentechnik GmbH - Linz, Austria. The described tests were performed in full test facility of DSD Linz, in “Easter 2015 PC-Crash Seminar”. In all crashes we obtaining results from both dummy placed in impacted and hits car. The novelty of the paper are the comparisons of data set from each of driver (dummy) of two cars involved in each of six experimental crashes. Another novelty of this paper consists in possibilities to analyse the influences of structural historical cars solutions over deformation and loads in cases of traffic accidents involved. Paper's conclusions can be future used for car passive safety improvement.

Design of a Pressure Sensor Based on Optical Fiber Bragg Grating Lateral Deformation

PubMed Central

Urban, Frantisek; Kadlec, Jaroslav; Vlach, Radek; Kuchta, Radek

2010-01-01

This paper describes steps involved in the design and realization of a new type of pressure sensor based on the optical fiber Bragg grating. A traditional pressure sensor has very limited usage in heavy industrial environments, particularly in explosive or electromagnetically noisy environments. Utilization of optics in these environments eliminates all surrounding influences. An initial motivation for our development was the research, experimental validation, and realization of a complex smart pressure sensor based on the optical principle. The main benefit of this solution consists of increasing sensitivity, resistance to electromagnetic interference, dimensions, and potential increased accuracy. PMID:22163521

Real-time control systems: feedback, scheduling and robustness

NASA Astrophysics Data System (ADS)

Simon, Daniel; Seuret, Alexandre; Sename, Olivier

2017-08-01

The efficient control of real-time distributed systems, where continuous components are governed through digital devices and communication networks, needs a careful examination of the constraints arising from the different involved domains inside co-design approaches. Thanks to the robustness of feedback control, both new control methodologies and slackened real-time scheduling schemes are proposed beyond the frontiers between these traditionally separated fields. A methodology to design robust aperiodic controllers is provided, where the sampling interval is considered as a control variable of the system. Promising experimental results are provided to show the feasibility and robustness of the approach.

Accelerating Biomedical Research in Designing Diagnostic Assays, Drugs, and Vaccines

DTIC Science & Technology

2010-10-01

biodefense. For example, USAMRIID researchers are using Dovis to initiate drug discovery efforts against the ricin A-chain toxin and the Ebola virus...in host cell invasion and bacterial toxin production). Traditional experimental methods to determine the functions of proteins encoded in genomic...readily modeled. A second study involved determining the pro- tein structure of VP24, the smallest protein in the Ebola and Marburg virus genomes.9

Effects of a Peer Helping Training Program on Helping Skills and Self-Growth of Peer Helpers

ERIC Educational Resources Information Center

Aladag, Mine; Tezer, Esin

2009-01-01

The purpose of this study was to develop a peer helping training program for university students in Turkey and to examine its effectiveness in improving the helping skills and self-growth of peer helpers. A pre-test, post-test, follow-up-test experimental design, involving a treatment and control group, was carried out with a total sample of 31…

Investigating the Role of Context in Experimental Research Involving the Use of Digital Media for the Learning of Mathematics: Boundary Objects as Vehicles for Integration

ERIC Educational Resources Information Center

Kynigos, Chronis; Psycharis, Giorgos

2009-01-01

The paper describes a study of the contexts of six teams, expert in research and development of digital media for learning mathematics, who cross-experimented in classrooms with the use of each other's artefacts. Contextual issues regarding the designed tasks and technologies, the socio-systemic milieu and the ways in which the researchers worked…

Synchrony and exertion during dance independently raise pain threshold and encourage social bonding

PubMed Central

Tarr, Bronwyn; Launay, Jacques; Cohen, Emma; Dunbar, Robin

2015-01-01

Group dancing is a ubiquitous human activity that involves exertive synchronized movement to music. It is hypothesized to play a role in social bonding, potentially via the release of endorphins, which are analgesic and reward-inducing, and have been implicated in primate social bonding. We used a 2 × 2 experimental design to examine effects of exertion and synchrony on bonding. Both demonstrated significant independent positive effects on pain threshold (a proxy for endorphin activation) and in-group bonding. This suggests that dance which involves both exertive and synchronized movement may be an effective group bonding activity. PMID:26510676

American Recovery and Reinvestment Act of 2009: Final Report on Customer Acceptance, Retention, and Response to Time-Based Rates from Consumer Behavior Studies

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

Cappers, Peter; Scheer, Rich

Time-based rate programs, enabled by utility investments in advanced metering infrastructure (AMI), are increasingly being considered by utilities as tools to reduce peak demand and enable customers to better manage consumption and costs. Under the Smart Grid Investment Grant Program (SGIG), the U.S. Department of Energy (DOE) partnered with several electric utilities to conduct consumer behavior studies (CBS). The goals involved applying randomized and controlled experimental designs for estimating customer responses more precisely and credibly to advance understanding of time-based rates and customer systems, and provide new information for improving program designs, implementation strategies, and evaluations. The intent was tomore » produce more robust and credible analysis of impacts, costs, benefits, and lessons learned and assist utility and regulatory decision makers in evaluating investment opportunities involving time-based rates.« less

Laboratory investigations of earthquake dynamics

NASA Astrophysics Data System (ADS)

Xia, Kaiwen

In this thesis this will be attempted through controlled laboratory experiments that are designed to mimic natural earthquake scenarios. The earthquake dynamic rupturing process itself is a complicated phenomenon, involving dynamic friction, wave propagation, and heat production. Because controlled experiments can produce results without assumptions needed in theoretical and numerical analysis, the experimental method is thus advantageous over theoretical and numerical methods. Our laboratory fault is composed of carefully cut photoelastic polymer plates (Homahte-100, Polycarbonate) held together by uniaxial compression. As a unique unit of the experimental design, a controlled exploding wire technique provides the triggering mechanism of laboratory earthquakes. Three important components of real earthquakes (i.e., pre-existing fault, tectonic loading, and triggering mechanism) correspond to and are simulated by frictional contact, uniaxial compression, and the exploding wire technique. Dynamic rupturing processes are visualized using the photoelastic method and are recorded via a high-speed camera. Our experimental methodology, which is full-field, in situ, and non-intrusive, has better control and diagnostic capacity compared to other existing experimental methods. Using this experimental approach, we have investigated several problems: dynamics of earthquake faulting occurring along homogeneous faults separating identical materials, earthquake faulting along inhomogeneous faults separating materials with different wave speeds, and earthquake faulting along faults with a finite low wave speed fault core. We have observed supershear ruptures, subRayleigh to supershear rupture transition, crack-like to pulse-like rupture transition, self-healing (Heaton) pulse, and rupture directionality.

True and Quasi-Experimental Designs. ERIC/AE Digest.

ERIC Educational Resources Information Center

Gribbons, Barry; Herman, Joan

Among the different types of experimental design are two general categories: true experimental designs and quasi- experimental designs. True experimental designs include more than one purposively created group, common measured outcomes, and random assignment. Quasi-experimental designs are commonly used when random assignment is not practical or…

Parametric pendulum based wave energy converter

NASA Astrophysics Data System (ADS)

Yurchenko, Daniil; Alevras, Panagiotis

2018-01-01

The paper investigates the dynamics of a novel wave energy converter based on the parametrically excited pendulum. The herein developed concept of the parametric pendulum allows reducing the influence of the gravity force thereby significantly improving the device performance at a regular sea state, which could not be achieved in the earlier proposed original point-absorber design. The suggested design of a wave energy converter achieves a dominant rotational motion without any additional mechanisms, like a gearbox, or any active control involvement. Presented numerical results of deterministic and stochastic modeling clearly reflect the advantage of the proposed design. A set of experimental results confirms the numerical findings and validates the new design of a parametric pendulum based wave energy converter. Power harvesting potential of the novel device is also presented.

Experimental evaluation of a breadboard heat and product-water removal system for a space-power fuel cell designed with static water removal and evaporative cooling

NASA Technical Reports Server (NTRS)

Hagedorn, N. H.; Prokipius, P. R.

1977-01-01

A test program was conducted to evaluate the design of a heat and product-water removal system to be used with fuel cell having static water removal and evaporative cooling. The program, which was conducted on a breadboard version of the system, provided a general assessment of the design in terms of operational integrity and transient stability. This assessment showed that, on the whole, the concept appears to be inherently sound but that in refining this design, several facets will require additional study. These involve interactions between pressure regulators in the pumping loop that occur when they are not correctly matched and the question of whether an ejector is necessary in the system.

Standardization of the experimental autoimmune myasthenia gravis (EAMG) model by immunization of rats with Torpedo californica acetylcholine receptors — Recommendations for methods and experimental designs

PubMed Central

Losen, Mario; Martinez-Martinez, Pilar; Molenaar, Peter C.; Lazaridis, Konstantinos; Tzartos, Socrates; Brenner, Talma; Duan, Rui-Sheng; Luo, Jie; Lindstrom, Jon; Kusner, Linda

2015-01-01

Myasthenia gravis (MG) with antibodies against the acetylcholine receptor (AChR) is characterized by a chronic, fatigable weakness of voluntary muscles. The production of autoantibodies involves the dysregulation of T cells which provide the environment for the development of autoreactive B cells. The symptoms are caused by destruction of the postsynaptic membrane and degradation of the AChR by IgG autoantibodies, predominantly of the G1 and G3 subclasses. Active immunization of animals with AChR from mammalian muscles, AChR from Torpedo or Electrophorus electric organs, and recombinant or synthetic AChR fragments generates a chronic model of MG, termed experimental autoimmune myasthenia gravis (EAMG). This model covers cellular mechanisms involved in the immune response against the AChR, e.g. antigen presentation, T cell-help and regulation, B cell selection and differentiation into plasma cells. Our aim is to define standard operation procedures and recommendations for the rat EAMG model using purified AChR from the Torpedo californica electric organ, in order to facilitate more rapid translation of preclinical proof of concept or efficacy studies into clinical trials and, ultimately, clinical practice. PMID:25796590

Evaluating two process scale chromatography column header designs using CFD.

PubMed

Johnson, Chris; Natarajan, Venkatesh; Antoniou, Chris

2014-01-01

Chromatography is an indispensable unit operation in the downstream processing of biomolecules. Scaling of chromatographic operations typically involves a significant increase in the column diameter. At this scale, the flow distribution within a packed bed could be severely affected by the distributor design in process scale columns. Different vendors offer process scale columns with varying design features. The effect of these design features on the flow distribution in packed beds and the resultant effect on column efficiency and cleanability needs to be properly understood in order to prevent unpleasant surprises on scale-up. Computational Fluid Dynamics (CFD) provides a cost-effective means to explore the effect of various distributor designs on process scale performance. In this work, we present a CFD tool that was developed and validated against experimental dye traces and tracer injections. Subsequently, the tool was employed to compare and contrast two commercially available header designs. © 2014 American Institute of Chemical Engineers.

A processing centre for the CNES CE-GPS experimentation

NASA Technical Reports Server (NTRS)

Suard, Norbert; Durand, Jean-Claude

1994-01-01

CNES is involved in a GPS (Global Positioning System) geostationary overlay experimentation. The purpose of this experimentation is to test various new techniques in order to select the optimal station synchronization method, as well as the geostationary spacecraft orbitography method. These new techniques are needed to develop the Ranging GPS Integrity Channel services. The CNES experimentation includes three transmitting/receiving ground stations (manufactured by IN-SNEC), one INMARSAT 2 C/L band transponder and a processing center named STE (Station de Traitements de l'Experimentation). Not all the techniques to be tested are implemented, but the experimental system has to include several functions; part of the future system simulation functions, such as a servo-loop function, and in particular a data collection function providing for rapid monitoring of system operation, analysis of existing ground station processes, and several weeks of data coverage for other scientific studies. This paper discusses system architecture and some criteria used in its design, as well as the monitoring function, the approach used to develop a low-cost and short-life processing center in collaboration with a CNES sub-contractor (ATTDATAID), and some results.

Theoretical and Experimental Estimations of Volumetric Inductive Phase Shift in Breast Cancer Tissue

NASA Astrophysics Data System (ADS)

González, C. A.; Lozano, L. M.; Uscanga, M. C.; Silva, J. G.; Polo, S. M.

2013-04-01

Impedance measurements based on magnetic induction for breast cancer detection has been proposed in some studies. This study evaluates theoretical and experimentally the use of a non-invasive technique based on magnetic induction for detection of patho-physiological conditions in breast cancer tissue associated to its volumetric electrical conductivity changes through inductive phase shift measurements. An induction coils-breast 3D pixel model was designed and tested. The model involves two circular coils coaxially centered and a human breast volume centrally placed with respect to the coils. A time-harmonic numerical simulation study addressed the effects of frequency-dependent electrical properties of tumoral tissue on the volumetric inductive phase shift of the breast model measured with the circular coils as inductor and sensor elements. Experimentally; five female volunteer patients with infiltrating ductal carcinoma previously diagnosed by the radiology and oncology departments of the Specialty Clinic for Women of the Mexican Army were measured by an experimental inductive spectrometer and the use of an ergonomic inductor-sensor coil designed to estimate the volumetric inductive phase shift in human breast tissue. Theoretical and experimental inductive phase shift estimations were developed at four frequencies: 0.01, 0.1, 1 and 10 MHz. The theoretical estimations were qualitatively in agreement with the experimental findings. Important increments in volumetric inductive phase shift measurements were evident at 0.01MHz in theoretical and experimental observations. The results suggest that the tested technique has the potential to detect pathological conditions in breast tissue associated to cancer by non-invasive monitoring. Further complementary studies are warranted to confirm the observations.

Development of a flexible microfluidic system integrating magnetic micro-actuators for trapping biological species

NASA Astrophysics Data System (ADS)

Fulcrand, R.; Jugieu, D.; Escriba, C.; Bancaud, A.; Bourrier, D.; Boukabache, A.; Gué, A. M.

2009-10-01

A flexible microfluidic system embedding microelectromagnets has been designed, modeled and fabricated by using a photosensitive resin as structural material. The fabrication process involves the integration of micro-coils in a multilayer SU-8 microfluidic system by combining standard electroplating and dry films lamination. This technique offers numerous advantages in terms of integration, biocompatibility and chemical resistance. Various designs of micro-coils, including spiral, square or serpentine wires, have been simulated and experimentally tested. It has been established that thermal dissipation in micro-coils depends strongly on the number of turns and current density but remains compatible with biological applications. Real-time experimentations show that these micro-actuators are efficient in trapping magnetic micro-beads without any external field source or a permanent magnet and highlight that the size of microfluidic channels has been adequately designed for optimal trapping. Moreover, we trap magnetic beads in less than 2 s and release them instantaneously into the micro-channel. The actuation solely relies on electric fields, which are easier to control than standard magneto-fluidic modules.

A systematic review of interventions to increase the use of standardized outcome measures by rehabilitation professionals.

PubMed

Colquhoun, Heather L; Lamontagne, Marie-Eve; Duncan, Edward As; Fiander, Michelle; Champagne, Catherine; Grimshaw, Jeremy M

2017-03-01

To determine the types and effectiveness of interventions to increase the knowledge about, attitudes towards, and use of standardized outcome measures in rehabilitation professionals. An electronic search using Medline, EMBASE, PsycINFO, CINAHL, Ergonomics Abstracts, Sports Discus. The search is current to February 2016. All study designs testing interventions were included as were all provider and patient types. Two reviewers independently conducted a title and abstract review, followed by a full-text review. Two reviewers independently extracted a priori variables and used consensus for disagreements. Quality assessment was conducted using the Assessment of Quantitative Studies published by the Effective Public Health Practice Group. We identified 11 studies involving at least 1200 providers. Nine of the studies showed improvements in outcome measure use rates but only three of these studies used an experimental or quasi-experimental design. Eight of the studies used an educational approach in the intervention and three used audit and feedback. Poor intervention description and quality of studies limited recommendations. Increased attention to testing interventions focused on known barriers, matched to behavior change techniques, and with stronger designs is warranted.

Use Of Zernike Polynomials And Interferometry In The Optical Design And Assembly Of Large Carbon-Dioxide Laser Systems

NASA Astrophysics Data System (ADS)

Viswanathan, V. K.

1982-02-01

This paper describes the need for non-raytracing schemes in the optical design and analysis of large carbon-dioxide lasers like the Gigawatt,1 Gemini, 2 and Helios3 lasers currently operational at Los Alamos, and the Antares 4 laser fusion system under construction. The scheme currently used at Los Alamos involves characterizing the various optical components with a Zernike polynomial sets obtained by the digitization6 of experimentally produced interferograms of the components. A Fast Fourier Transform code then propagates the complex amplitude and phase of the beam through the whole system and computes the optical parameters of interest. The analysis scheme is illustrated through examples of the Gigawatt, Gemini, and Helios systems. A possible way of using the Zernike polynomials in optical design problems of this type is discussed. Comparisons between the computed values and experimentally obtained results are made and it is concluded that this appears to be a valid approach. As this is a review article, some previously published results are also used where relevant.

An integrated ball projection technology for the study of dynamic interceptive actions.

PubMed

Stone, J A; Panchuk, D; Davids, K; North, J S; Fairweather, I; Maynard, I W

2014-12-01

Dynamic interceptive actions, such as catching or hitting a ball, are important task vehicles for investigating the complex relationship between cognition, perception, and action in performance environments. Representative experimental designs have become more important recently, highlighting the need for research methods to ensure that the coupling of information and movement is faithfully maintained. However, retaining representative design while ensuring systematic control of experimental variables is challenging, due to the traditional tendency to employ methods that typically involve use of reductionist motor responses such as buttonpressing or micromovements. Here, we outline the methodology behind a custom-built, integrated ball projection technology that allows images of advanced visual information to be synchronized with ball projection. This integrated technology supports the controlled presentation of visual information to participants while they perform dynamic interceptive actions. We discuss theoretical ideas behind the integration of hardware and software, along with practical issues resolved in technological design, and emphasize how the system can be integrated with emerging developments such as mixed reality environments. We conclude by considering future developments and applications of the integrated projection technology for research in human movement behaviors.

A numerical study of mixing in supersonic combustors with hypermixing injectors

NASA Technical Reports Server (NTRS)

Lee, J.

1993-01-01

A numerical study was conducted to evaluate the performance of wall mounted fuel-injectors designed for potential Supersonic Combustion Ramjet (SCRAM-jet) engine applications. The focus of this investigation was to numerically simulate existing combustor designs for the purpose of validating the numerical technique and the physical models developed. Three different injector designs of varying complexity were studied to fully understand the computational implications involved in accurate predictions. A dual transverse injection system and two streamwise injector designs were studied. The streamwise injectors were designed with swept ramps to enhance fuel-air mixing and combustion characteristics at supersonic speeds without the large flow blockage and drag contribution of the transverse injection system. For this study, the Mass-Average Navier-Stokes equations and the chemical species continuity equations were solved. The computations were performed using a finite-volume implicit numerical technique and multiple block structured grid system. The interfaces of the multiple block structured grid systems were numerically resolved using the flux-conservative technique. Detailed comparisons between the computations and existing experimental data are presented. These comparisons show that numerical predictions are in agreement with the experimental data. These comparisons also show that a number of turbulence model improvements are needed for accurate combustor flowfield predictions.

A numerical study of mixing in supersonic combustors with hypermixing injectors

NASA Technical Reports Server (NTRS)

Lee, J.

1992-01-01

A numerical study was conducted to evaluate the performance of wall mounted fuel-injectors designed for potential Supersonic Combustion Ramjet (SCRAM-jet) engine applications. The focus of this investigation was to numerically simulate existing combustor designs for the purpose of validating the numerical technique and the physical models developed. Three different injector designs of varying complexity were studied to fully understand the computational implications involved in accurate predictions. A dual transverse injection system and two streamwise injector designs were studied. The streamwise injectors were designed with swept ramps to enhance fuel-air mixing and combustion characteristics at supersonic speeds without the large flow blockage and drag contribution of the transverse injection system. For this study, the Mass-Averaged Navier-Stokes equations and the chemical species continuity equations were solved. The computations were performed using a finite-volume implicit numerical technique and multiple block structured grid system. The interfaces of the multiple block structured grid systems were numerically resolved using the flux-conservative technique. Detailed comparisons between the computations and existing experimental data are presented. These comparisons show that numerical predictions are in agreement with the experimental data. These comparisons also show that a number of turbulence model improvements are needed for accurate combustor flowfield predictions.

What do we mean by Human-Centered Design of Life-Critical Systems?

PubMed

Boy, Guy A

2012-01-01

Human-centered design is not a new approach to design. Aerospace is a good example of a life-critical systems domain where participatory design was fully integrated, involving experimental test pilots and design engineers as well as many other actors of the aerospace engineering community. This paper provides six topics that are currently part of the requirements of the Ph.D. Program in Human-Centered Design of the Florida Institute of Technology (FIT.) This Human-Centered Design program offers principles, methods and tools that support human-centered sustainable products such as mission or process control environments, cockpits and hospital operating rooms. It supports education and training of design thinkers who are natural leaders, and understand complex relationships among technology, organizations and people. We all need to understand what we want to do with technology, how we should organize ourselves to a better life and finally find out whom we are and have become. Human-centered design is being developed for all these reasons and issues.

Avalanching strain dynamics during the hydriding phase transformation in individual palladium nanoparticles

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

Ulvestad, A.; Welland, M. J.; Collins, S. S. E.

2015-12-11

Phase transitions in reactive environments are crucially important in energy and information storage, catalysis and sensors. Nanostructuring active particles can yield faster charging/ discharging kinetics, increased lifespan and record catalytic activities. However, establishing the causal link between structure and function is challenging for nanoparticles, as ensemble measurements convolve intrinsic single-particle properties with sample diversity. Here we study the hydriding phase transformation in individual palladium nanocubes in situ using coherent X-ray diffractive imaging. The phase transformation dynamics, which involve the nucleation and propagation of a hydrogen-rich region, are dependent on absolute time (aging) and involve intermittent dynamics (avalanching). A hydrogen-rich surfacemore » layer dominates the crystal strain in the hydrogen-poor phase, while strain inversion occurs at the cube corners in the hydrogen-rich phase. A three-dimensional phase-field model is used to interpret the experimental results. In conclusion, our experimental and theoretical approach provides a general framework for designing and optimizing phase transformations for single nanocrystals in reactive environments.« less

Experimental Study of Grit Particle Enhancement in Non-Shock Ignition

NASA Astrophysics Data System (ADS)

Browning, Richard V.; Peterson, Paul D.; Roemer, Edward L.; Oldenborg, Michael R.; Thompson, Darla G.; Deluca, Racci

2006-07-01

The drop weight impact test is the most commonly used configuration for evaluating sensitivity of explosives to non-shock ignition. Although developed 60 years ago and widely used both as a material compression test and as a test bed for understanding the ignition process itself, little is known about the flow mechanisms or involvement of grit particles as sensitizing agents. In this paper, we present the results of a series of experiments designed to study the flow mechanisms and events leading up to ignition. The experimental configuration used involves two pellet sizes, 3 and 5 mm in diameter, tested with three conditions: (1) smooth steel anvils, (2) standard flint sandpaper, and (3) shed grit particles loaded between the steel anvils and the pellet faces. Diagnostics include optical micrographs, and scanning electron micrographs. Un-reacted samples show a variety of morphologies, including what appear to be quenched reaction sites, even at very low drop heights. Quasi-static crushing experiments were also done to quantify load-time histories.

Experimental Study of Grit Particle Enhancement in Non-Shock Ignition of PBX 9501

NASA Astrophysics Data System (ADS)

Peterson, Paul

2005-07-01

The drop weight impact test is the most commonly used configuration for evaluating sensitivity of explosives to non-shock ignition. Although developed 60 years ago and widely used both as a material compression test and as a test bed for understanding the ignition process itself, little is known about the flow mechanisms or involvement of grit particles as sensitizing agents. In this paper we present the results of a series of experiments designed to study the flow mechanisms and events leading up to ignition. The experimental configuration used involves two pellet sizes, 3 and 5 mm in diameter, tested in three conditions, (1) with smooth steel anvils, (2) with standard flint sandpaper, and (3) with shed grit particles loaded between the steel anvils and the pellet faces. Diagnostics include optical micrographs, and scanning electron micrographs. Un-reacted samples show a variety of morphologies, including what appear to be quenched reaction sites, even at very low drop heights. Quasi-static crushing experiments were also done to quantify load-time histories.

Numerical Investigation of 'Transonic Resonance' with a Convergent-Divergent Nozzle

NASA Technical Reports Server (NTRS)

Loh, Ching Y.; Zaman, K. B. M. Q.

2002-01-01

At pressure ratios lower than the design value, convergent-divergent (C-D) nozzles often undergo a flow resonance accompanied by the emission of acoustic tones. The phenomenon, driven by the unsteady shock within the divergent section of the nozzle, has been studied experimentally by Zaman et al. In this paper, the space-time conservation element solution element (CE/SE) method is employed to numerically investigate the phenomenon. The computations are performed for a given nozzle geometry for several different pressure ratios. Sustained 'limit cycle' oscillations are encountered in all cases. The oscillation frequencies, their variation with pressure ratio including a 'stage jump', agree well with the experimental results. The unsteady flow data confirm that stage 1 of the resonance (fundamental) involves a one-quarter standing wave while stage 2 (third harmonic) involves a three-quarter standing wave within the divergent section of the nozzle. Details of the shock motion, and the flow and near acoustic field, are documented for one case each of stages 1 and 2.

On the Choice of Adequate Randomization Ranges for Limiting the Use of Unwanted Cues in Same-Different, Dual-Pair, and Oddity Tasks

PubMed Central

Dai, Huanping; Micheyl, Christophe

2010-01-01

A major concern when designing a psychophysical experiment is that participants may use another stimulus feature (“cue”) than that intended by the experimenter. One way to avoid this involves applying random variations to the corresponding feature across stimulus presentations, to make the “unwanted” cue unreliable. An important question facing experimenters who use this randomization (“roving”) technique is: How large should the randomization range be to ensure that participants cannot achieve a certain proportion correct (PC) by using the unwanted cue, while at the same time avoiding unnecessary interference of the randomization with task performance? Previous publications have provided formulas for the selection of adequate randomization ranges in yes-no and multiple-alternative, forced-choice tasks. In this article, we provide figures and tables, which can be used to select randomization ranges that are better suited to experiments involving a same-different, dual-pair, or oddity task. PMID:20139466

Avalanching strain dynamics during the hydriding phase transformation in individual palladium nanoparticles

NASA Astrophysics Data System (ADS)

Ulvestad, A.; Welland, M. J.; Collins, S. S. E.; Harder, R.; Maxey, E.; Wingert, J.; Singer, A.; Hy, S.; Mulvaney, P.; Zapol, P.; Shpyrko, O. G.

2015-12-01

Phase transitions in reactive environments are crucially important in energy and information storage, catalysis and sensors. Nanostructuring active particles can yield faster charging/discharging kinetics, increased lifespan and record catalytic activities. However, establishing the causal link between structure and function is challenging for nanoparticles, as ensemble measurements convolve intrinsic single-particle properties with sample diversity. Here we study the hydriding phase transformation in individual palladium nanocubes in situ using coherent X-ray diffractive imaging. The phase transformation dynamics, which involve the nucleation and propagation of a hydrogen-rich region, are dependent on absolute time (aging) and involve intermittent dynamics (avalanching). A hydrogen-rich surface layer dominates the crystal strain in the hydrogen-poor phase, while strain inversion occurs at the cube corners in the hydrogen-rich phase. A three-dimensional phase-field model is used to interpret the experimental results. Our experimental and theoretical approach provides a general framework for designing and optimizing phase transformations for single nanocrystals in reactive environments.

Avalanching strain dynamics during the hydriding phase transformation in individual palladium nanoparticles

PubMed Central

Ulvestad, A.; Welland, M. J.; Collins, S. S. E.; Harder, R.; Maxey, E.; Wingert, J.; Singer, A.; Hy, S.; Mulvaney, P.; Zapol, P.; Shpyrko, O. G.

2015-01-01

Phase transitions in reactive environments are crucially important in energy and information storage, catalysis and sensors. Nanostructuring active particles can yield faster charging/discharging kinetics, increased lifespan and record catalytic activities. However, establishing the causal link between structure and function is challenging for nanoparticles, as ensemble measurements convolve intrinsic single-particle properties with sample diversity. Here we study the hydriding phase transformation in individual palladium nanocubes in situ using coherent X-ray diffractive imaging. The phase transformation dynamics, which involve the nucleation and propagation of a hydrogen-rich region, are dependent on absolute time (aging) and involve intermittent dynamics (avalanching). A hydrogen-rich surface layer dominates the crystal strain in the hydrogen-poor phase, while strain inversion occurs at the cube corners in the hydrogen-rich phase. A three-dimensional phase-field model is used to interpret the experimental results. Our experimental and theoretical approach provides a general framework for designing and optimizing phase transformations for single nanocrystals in reactive environments. PMID:26655832

Biosorption of Ag(I) from aqueous solutions by Klebsiella sp. 3S1.

PubMed

Muñoz, Antonio Jesús; Espínola, Francisco; Ruiz, Encarnación

2017-05-05

This study investigated the potential ability of Klebsiella sp. 3S1 to remove silver cations from aqueous solutions. The selected strain is a ubiquitous bacterium selected from among several microorganisms that had been isolated from wastewaters. To optimise the operating conditions in the biosorption process, a Rotatable Central Composite Experimental Design was developed establishing pH, temperature and biomass concentration as independent variables. Interaction mechanisms involved were analysed through kinetic and equilibrium studies. The experimental results suit pseudo-second order kinetics with two biosorption stages, being the first almost instantly. The Langmuir equilibrium model predicted a maximum capacity of biosorption (q) of 114.1mg Ag/g biomass. The study of the mechanisms involved in the biosorption was completed by employing advanced techniques which revealed that both bacterium-surface interactions and intracellular bioaccumulation participate in silver removal from aqueous solutions. The ability of Klebsiella sp. 3S1 to form silver chloride nanoparticles with interesting potential applications was also discussed. Copyright © 2017 Elsevier B.V. All rights reserved.

Experimental characterization of an adaptive aileron: lab tests and FE correlation

NASA Astrophysics Data System (ADS)

Amendola, Gianluca; Dimino, Ignazio; Amoroso, Francesco; Pecora, Rosario

2016-04-01

Like any other technology, morphing has to demonstrate system level performance benefits prior to implementation onto a real aircraft. The current status of morphing structures research efforts (as the ones, sponsored by the European Union) involves the design of several subsystems which have to be individually tested in order to consolidate their general performance in view of the final integration into a flyable device. This requires a fundamental understanding of the interaction between aerodynamic, structure and control systems. Important worldwide research collaborations were born in order to exchange acquired experience and better investigate innovative technologies devoted to morphing structures. The "Adaptive Aileron" project represents a joint cooperation between Canadian and Italian research centers and leading industries. In this framework, an overview of the design, manufacturing and testing of a variable camber aileron for a regional aircraft is presented. The key enabling technology for the presented morphing aileron is the actuation structural system, integrating a suitable motor and a load-bearing architecture. The paper describes the lab test campaign of the developed device. The implementation of a distributed actuation system fulfills the actual tendency of the aeronautical research to move toward the use of electrical power to supply non-propulsive systems. The aileron design features are validated by targeted experimental tests, demonstrating both its adaptive capability and robustness under operative loads and its dynamic behavior for further aeroelastic analyses. The experimental results show a satisfactory correlation with the numerical expectations thus validating the followed design approach.

Implementation of a Collaborative Series of Classroom-Based Undergraduate Research Experiences Spanning Chemical Biology, Biochemistry, and Neurobiology.

PubMed

Kowalski, Jennifer R; Hoops, Geoffrey C; Johnson, R Jeremy

2016-01-01

Classroom undergraduate research experiences (CUREs) provide students access to the measurable benefits of undergraduate research experiences (UREs). Herein, we describe the implementation and assessment of a novel model for cohesive CUREs focused on central research themes involving faculty research collaboration across departments. Specifically, we implemented three collaborative CUREs spanning chemical biology, biochemistry, and neurobiology that incorporated faculty members' research interests and revolved around the central theme of visualizing biological processes like Mycobacterium tuberculosis enzyme activity and neural signaling using fluorescent molecules. Each CURE laboratory involved multiple experimental phases and culminated in novel, open-ended, and reiterative student-driven research projects. Course assessments showed CURE participation increased students' experimental design skills, attitudes and confidence about research, perceived understanding of the scientific process, and interest in science, technology, engineering, and mathematics disciplines. More than 75% of CURE students also engaged in independent scientific research projects, and faculty CURE contributors saw substantial increases in research productivity, including increased undergraduate student involvement and academic outputs. Our collaborative CUREs demonstrate the advantages of multicourse CUREs for achieving increased faculty research productivity and traditional CURE-associated student learning and attitude gains. Our collaborative CURE design represents a novel CURE model for ongoing laboratory reform that benefits both faculty and students. © 2016 J. R. Kowalski et al. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

16 CFR 1702.10 - Human experimental data involving the testing of human subjects.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 16 Commercial Practices 2 2011-01-01 2011-01-01 false Human experimental data involving the testing of human subjects. 1702.10 Section 1702.10 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION... PACKAGING ACT REQUIREMENTS; PETITION PROCEDURES AND REQUIREMENTS § 1702.10 Human experimental data involving...

16 CFR 1702.10 - Human experimental data involving the testing of human subjects.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 16 Commercial Practices 2 2012-01-01 2012-01-01 false Human experimental data involving the testing of human subjects. 1702.10 Section 1702.10 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION... PACKAGING ACT REQUIREMENTS; PETITION PROCEDURES AND REQUIREMENTS § 1702.10 Human experimental data involving...

16 CFR 1702.10 - Human experimental data involving the testing of human subjects.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 16 Commercial Practices 2 2014-01-01 2014-01-01 false Human experimental data involving the testing of human subjects. 1702.10 Section 1702.10 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION... PACKAGING ACT REQUIREMENTS; PETITION PROCEDURES AND REQUIREMENTS § 1702.10 Human experimental data involving...

16 CFR 1702.10 - Human experimental data involving the testing of human subjects.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Human experimental data involving the testing of human subjects. 1702.10 Section 1702.10 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION... PACKAGING ACT REQUIREMENTS; PETITION PROCEDURES AND REQUIREMENTS § 1702.10 Human experimental data involving...

Part weight verification between simulation and experiment of plastic part in injection moulding process

NASA Astrophysics Data System (ADS)

Amran, M. A. M.; Idayu, N.; Faizal, K. M.; Sanusi, M.; Izamshah, R.; Shahir, M.

2016-11-01

In this study, the main objective is to determine the percentage difference of part weight between experimental and simulation work. The effect of process parameters on weight of plastic part is also investigated. The process parameters involved were mould temperature, melt temperature, injection time and cooling time. Autodesk Simulation Moldflow software was used to run the simulation of the plastic part. Taguchi method was selected as Design of Experiment to conduct the experiment. Then, the simulation result was validated with the experimental result. It was found that the minimum and maximum percentage of differential of part weight between simulation and experimental work are 0.35 % and 1.43 % respectively. In addition, the most significant parameter that affected part weight is the mould temperature, followed by melt temperature, injection time and cooling time.

Experimental investigation of a four-qubit linear-optical quantum logic circuit

NASA Astrophysics Data System (ADS)

Stárek, R.; Mičuda, M.; Miková, M.; Straka, I.; Dušek, M.; Ježek, M.; Fiurášek, J.

2016-09-01

We experimentally demonstrate and characterize a four-qubit linear-optical quantum logic circuit. Our robust and versatile scheme exploits encoding of two qubits into polarization and path degrees of single photons and involves two crossed inherently stable interferometers. This approach allows us to design a complex quantum logic circuit that combines a genuine four-qubit C3Z gate and several two-qubit and single-qubit gates. The C3Z gate introduces a sign flip if and only if all four qubits are in the computational state |1>. We verify high-fidelity performance of this central four-qubit gate using Hofmann bounds on quantum gate fidelity and Monte Carlo fidelity sampling. We also experimentally demonstrate that the quantum logic circuit can generate genuine multipartite entanglement and we certify the entanglement with the use of suitably tailored entanglement witnesses.

Experimental investigation of a four-qubit linear-optical quantum logic circuit.

PubMed

Stárek, R; Mičuda, M; Miková, M; Straka, I; Dušek, M; Ježek, M; Fiurášek, J

2016-09-20

We experimentally demonstrate and characterize a four-qubit linear-optical quantum logic circuit. Our robust and versatile scheme exploits encoding of two qubits into polarization and path degrees of single photons and involves two crossed inherently stable interferometers. This approach allows us to design a complex quantum logic circuit that combines a genuine four-qubit C(3)Z gate and several two-qubit and single-qubit gates. The C(3)Z gate introduces a sign flip if and only if all four qubits are in the computational state |1〉. We verify high-fidelity performance of this central four-qubit gate using Hofmann bounds on quantum gate fidelity and Monte Carlo fidelity sampling. We also experimentally demonstrate that the quantum logic circuit can generate genuine multipartite entanglement and we certify the entanglement with the use of suitably tailored entanglement witnesses.

A framework for self-experimentation in personalized health.

PubMed

Karkar, Ravi; Zia, Jasmine; Vilardaga, Roger; Mishra, Sonali R; Fogarty, James; Munson, Sean A; Kientz, Julie A

2016-05-01

To describe an interdisciplinary and methodological framework for applying single case study designs to self-experimentation in personalized health. The authors examine the framework's applicability to various health conditions and present an initial case study with irritable bowel syndrome (IBS). An in-depth literature review was performed to develop the framework and to identify absolute and desired health condition requirements for the application of this framework. The authors developed mobile application prototypes, storyboards, and process flows of the framework using IBS as the case study. The authors conducted three focus groups and an online survey using a human-centered design approach for assessing the framework's feasibility. All 6 focus group participants had a positive view about our framework and volunteered to participate in future studies. Most stated they would trust the results because it was their own data being analyzed. They were most concerned about confounds, nonmeaningful measures, and erroneous assumptions on the timing of trigger effects. Survey respondents (N = 60) were more likely to be adherent to an 8- vs 12-day study length even if it meant lower confidence results. Implementation of the self-experimentation framework in a mobile application appears to be feasible for people with IBS. This framework can likely be applied to other health conditions. Considerations include the learning curve for teaching self-experimentation to non-experts and the challenges involved in operationalizing and customizing study designs. Using mobile technology to guide people through self-experimentation to investigate health questions is a feasible and promising approach to advancing personalized health. © The Author 2015. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Solar Pumped Solid State Lasers for Space Solar Power: Experimental Path

NASA Technical Reports Server (NTRS)

Fork, Richard L.; Carrington, Connie K.; Walker, Wesley W.; Cole, Spencer T.; Green, Jason J. A.; Laycock, Rustin L.

2003-01-01

We outline an experimentally based strategy designed to lead to solar pumped solid state laser oscillators useful for space solar power. Our method involves solar pumping a novel solid state gain element specifically designed to provide efficient conversion of sunlight in space to coherent laser light. Kilowatt and higher average power is sought from each gain element. Multiple such modular gain elements can be used to accumulate total average power of interest for power beaming in space, e.g., 100 kilowatts and more. Where desirable the high average power can also be produced as a train of pulses having high peak power (e.g., greater than 10(exp 10 watts). The modular nature of the basic gain element supports an experimental strategy in which the core technology can be validated by experiments on a single gain element. We propose to do this experimental validation both in terrestrial locations and also on a smaller scale in space. We describe a terrestrial experiment that includes diagnostics and the option of locating the laser beam path in vacuum environment. We describe a space based experiment designed to be compatible with the Japanese Experimental Module (JEM) on the International Space Station (ISS). We anticipate the gain elements will be based on low temperature (approx. 100 degrees Kelvin) operation of high thermal conductivity (k approx. 100 W/cm-K) diamond and sapphire (k approx. 4 W/cm-K). The basic gain element will be formed by sequences of thin alternating layers of diamond and Ti:sapphire with special attention given to the material interfaces. We anticipate this strategy will lead to a particularly simple, robust, and easily maintained low mass modelocked multi-element laser oscillator useful for space solar power.

A Multi-Disciplinary University Research Initiative in Hard and Soft Information Fusion: Overview, Research Strategies and Initial Results

DTIC Science & Technology

2010-07-01

Multisource Information Fusion ( CMIF ) along with a team including the Pennsylvania State University (PSU), Iona College (Iona), and Tennessee State...License. 14. ABSTRACT The University at Buffalo (UB) Center for Multisource Information Fusion ( CMIF ) along with a team including the Pennsylvania...of CMIF current research on methods for Test and Evaluation ([7], [8]) involving for example large- factor-space experimental design techniques ([9

Behavior Of Aircraft Components Under Crash-Type Loads

NASA Technical Reports Server (NTRS)

Carden, Huey D.; Boitnott, Richard L.; Fasanella, Edwin L.

1993-01-01

Report presents overview of research involving use of concepts of aircraft elements and substructures not necessarily designed or optimized with respect to energy-absorption or crash-loading considerations. Experimental and analytical data presented in report indicate some general trends in failure behaviors of class of composite-material structures including individual fuselage frames, skeleton subfloors with stringers and floor beams but without skin covering, and subfloors with skin added to frame/stringer arrangement.

Dynamic analysis for shuttle design verification

NASA Technical Reports Server (NTRS)

Fralich, R. W.; Green, C. E.; Rheinfurth, M. H.

1972-01-01

Two approaches that are used for determining the modes and frequencies of space shuttle structures are discussed. The first method, direct numerical analysis, involves finite element mathematical modeling of the space shuttle structure in order to use computer programs for dynamic structural analysis. The second method utilizes modal-coupling techniques of experimental verification made by vibrating only spacecraft components and by deducing modes and frequencies of the complete vehicle from results obtained in the component tests.

An ambient assisted living approach in designing domiciliary services combined with innovative technologies for patients with Alzheimer's disease: a case study.

PubMed

Cavallo, Filippo; Aquilano, Michela; Arvati, Marco

2015-02-01

Alzheimer's disease (AD) is one of the most disabling diseases to affect large numbers of elderly people worldwide. Because of the characteristics of this disease, patients with AD require daily assistance from service providers both in nursing homes and at home. Domiciliary assistance has been demonstrated to be cost effective and efficient in the first phase of the disease, helping to slow down the course of the illness, improve the quality of life and care, and extend independence for patients and caregivers. In this context, the aim of this work is to demonstrate the technical effectiveness and acceptability of an innovative domiciliary smart sensor system for providing domiciliary assistance to patients with AD which has been developed with an Ambient Assisted Living (AAL) approach. The design, development, testing, and evaluation of the innovative technological solution were performed by a multidisciplinary team. In all, 15 sociomedical operators and 14 patients with AD were directly involved in defining the end-users' needs and requirements, identifying design principles with acceptability and usability features and evaluating the technological solutions before and after the real experimentation. A modular technological system was produced to help caregivers continuously monitor the health status, safety, and daily activities of patients with AD. During the experimentation, the acceptability, utility, usability, and efficacy of this system were evaluated as quite positive. The experience described in this article demonstrated that AAL technologies are feasible and effective nowadays and can be actively used in assisting patients with AD in their homes. The extensive involvement of caregivers in the experimentation allowed to assess that there is, through the use of the technological system, a proven improvement in care performance and efficiency of care provision by both formal and informal caregivers and consequently an increase in the quality of life of patients, their relatives, and their caregivers. © The Author(s) 2014.

Quality by design approach of a pharmaceutical gel manufacturing process, part 1: determination of the design space.

PubMed

Rosas, Juan G; Blanco, Marcel; González, Josep M; Alcalá, Manel

2011-10-01

This work was conducted in the framework of a quality by design project involving the production of a pharmaceutical gel. Preliminary work included the identification of the quality target product profiles (QTPPs) from historical values for previously manufactured batches, as well as the critical quality attributes for the process (viscosity and pH), which were used to construct a D-optimal experimental design. The experimental design comprised 13 gel batches, three of which were replicates at the domain center intended to assess the reproducibility of the target process. The viscosity and pH models established exhibited very high linearity and negligible lack of fit (LOF). Thus, R(2) was 0.996 for viscosity and 0.975 for pH, and LOF was 0.53 for the former parameter and 0.84 for the latter. The process proved reproducible at the domain center. Water content and temperature were the most influential factors for viscosity, and water content and acid neutralized fraction were the most influential factors for pH. A desirability function was used to find the best compromise to optimize the QTPPs. The body of information was used to identify and define the design space for the process. A model capable of combining the two response variables into a single one was constructed to facilitate monitoring of the process. Copyright © 2011 Wiley-Liss, Inc.

Vibroacoustic Characterization of a New Hybrid Wing-Body Fuselage Concept

NASA Technical Reports Server (NTRS)

Allen, Albert R.; Przekop, Adam

2012-01-01

A lighter, more robust airframe design is required to withstand the loading inherent to next generation non cylindrical commercial airliners. The Pultruded Rod Stitched Efficient Unitized Structure concept, a highly integrated composite design involving a stitched and co-cured substructure, has been developed to meet such requirements. While this structure has been shown to meet the demanding out-of-plane loading requirements of the flat-sided pressurized cabin design, there are concerns that the stiff co-cured details will result in relatively high acoustic radiation efficiencies at frequencies well below the thin skin acoustic coincidence frequency. To address this concern and establish a set of baseline vibroacoustic characteristics, a representative test panel was fabricated and a suite of tests were conducted that involved measurements of panel vibration and radiated sound power during point force and diffuse acoustic field excitations. Experimental results are shown and compared with Finite Element and Statistical Energy Analysis model predictions through the use of modal and energy correlation techniques among others. The behavior of the structure subject to turbulent boundary layer excitation is also numerically examined.

Advanced propeller research

NASA Technical Reports Server (NTRS)

Groeneweg, John F.; Bober, Lawrence J.

1987-01-01

Resent results of aerodynamic and acoustic research on both single and counter-rotation propellers are reviewed. Data and analytical results are presented for three propellers: SR-7A, the single rotation design used in the NASA Propfan Test Assessment (PTA); and F7-A7, the 8+8 counterrotating design used in the proof-of-concept Unducted Fan (UDF) engine. In addition to propeller efficiencies, cruise and takeoff noise, and blade pressure data, off-design phenomena involving formation of leading edge vortices are described. Aerodynamic and acoustic computational results derived from three-dimensional Euler and acoustic radiation codes are presented. Research on unsteady flows, which are particularly important for understanding counterrotation interaction noise, unsteady loading effects on acoustics, and flutter or forced response is described. The first results of three-dimensional unsteady Euler solutions are illustrated for a single rotation propeller at an angle of attack and for a counterrotation propeller. Basic experimental and theoretical results from studies of the unsteady aerodynamics of oscillating cascades are outlined. Finally, advanced concepts involving swirl recovery vanes and ultra bypass ducted propellers are discussed.

A new hybrid electrospray Fourier transform mass spectrometer: design and performance characteristics.

PubMed

O'connor, Peter B; Pittman, Jason L; Thomson, Bruce A; Budnik, Bogdan A; Cournoyer, Jason C; Jebanathirajah, Judith; Lin, Cheng; Moyer, Susanne; Zhao, Cheng

2006-01-01

A new hybrid electrospray quadrupole Fourier transform mass spectrometry (FTMS) instrument design is shown and characterized. This instrument involves coupling an electrospray source and mass-resolving quadrupole, ion accumulation, and collision cell linear ion trap system developed by MDS Sciex with a home-built ion guide and ion cyclotron resonance (ICR) cell. The iterative progression of this design is shown. The final design involves a set of hexapole ion guides to transfer the ions from the accumulation/collision trap through the magnetic field gradient and into the cell. These hexapole ion guides are separated by a thin gate valve and two conduction limits to maintain the required <10(-9) mbar vacuum for FTICR. Low-attomole detection limits for a pure peptide are shown, 220 000 resolving power in broadband mode and 820 000 resolving power in narrow-band mode are demonstrated, and mass accuracy in the <2 ppm range is routinely available provided the signal is abundant, cleanly resolved, and internally calibrated. This instrument design provides high experimental flexibility, allowing Q2 CAD, SORI-CAD, IRMPD, and ECD experiments with selected ion accumulation as well as experiments such as nozzle skimmer dissociation. Initial top-down mass spectrometry experiments on a protein is shown using ECD.

Design of electrical stimulation bioreactors for cardiac tissue engineering.

PubMed

Tandon, N; Marsano, A; Cannizzaro, C; Voldman, J; Vunjak-Novakovic, G

2008-01-01

Electrical stimulation has been shown to improve functional assembly of cardiomyocytes in vitro for cardiac tissue engineering. Carbon electrodes were found in past studies to have the best current injection characteristics. The goal of this study was to develop rational experimental design principles for the electrodes and stimulation regime, in particular electrode configuration, electrode ageing, and stimulation amplitude. Carbon rod electrodes were compared via electrochemical impedance spectroscopy (EIS) and we identified a safety range of 0 to 8 V/cm by comparing excitation thresholds and maximum capture rates for neonatal rat cardiomyocytes cultured with electrical stimulation. We conclude with recommendations for studies involving carbon electrodes for cardiac tissue engineering.

Development of Meteorological Towers Using Advanced Composite Materials

NASA Astrophysics Data System (ADS)

Alshurafa, Sami A.

The research program involved both numerical and experimental work. The numerical analysis was conducted to simulate the static and dynamic behaviour of the 81 m meteorological FRP guyed tower under wind and ice loading. The FRP tower consisted of 16 segments each made of 3 cells connected together to form an equilateral triangle having equal sides of 450 mm. The segments were interconnected using internal sleeves. Various non-linear finite element models were developed to study a number of design parameters for the 81 m FRP tower such as, different laminates containing a variety of stacking sequences of laminate orientations with various thicknesses, different cable diameters, and appropriate guy cable spacing levels. The effect of pre-stressing the guy cables up to 10 % of their breaking strength was investigated. The effect of fibre volume fraction on the design of the FRP tower was also examined. Furthermore, an 8.6 m FRP tower segment was designed using the finite element analysis and subject to the same loading conditions experienced by the bottom section of the 81 m FRP tower. A modal analysis was carried out for both the 8.6 m FRP tower segment with and without a mass on the top as well as for the 81 m FRP guyed tower to evaluate the vibration performance of these towers. The experimental work involved extensive material testing to define the material properties for use in the analysis of the 81 m FRP tower. It also involved the design and fabrication of a special collapsible mandrel for fabricating the FRP cells for the 8.6 m tower segment. The 8.6 m tower was tested horizontally under static lateral loading to 80 % of its estimated failure load using a "whiffle tree" arrangement, in order to simulate a uniformly distributed wind loading. Later, the same FRP tower was erected in a vertical position and was tested with and without a mass on top under dynamic loading to obtain the natural frequencies. Lastly, a comparative study was conducted between two 81 m FRP towers having different fibre volume fractions and a steel tower having a circular cross section.

Enhancing the Ability of Experimental Autoimmune Encephalomyelitis to Serve as a More Rigorous Model of Multiple Sclerosis through Refinement of the Experimental Design

PubMed Central

Emerson, Mitchell R; Gallagher, Ryan J; Marquis, Janet G; LeVine, Steven M

2009-01-01

Advancing the understanding of the mechanisms involved in the pathogenesis of multiple sclerosis (MS) likely will lead to new and better therapeutics. Although important information about the disease process has been obtained from research on pathologic specimens, peripheral blood lymphocytes and MRI studies, the elucidation of detailed mechanisms has progressed largely through investigations using animal models of MS. In addition, animal models serve as an important tool for the testing of putative interventions. The most commonly studied model of MS is experimental autoimmune encephalomyelitis (EAE). This model can be induced in a variety of species and by various means, but there has been concern that the model may not accurately reflect the disease process, and more importantly, it may give rise to erroneous findings when it is used to test possible therapeutics. Several reasons have been given to explain the shortcomings of this model as a useful testing platform, but one idea provides a framework for improving the value of this model, and thus, it deserves careful consideration. In particular, the idea asserts that EAE studies are inadequately designed to enable appropriate evaluation of putative therapeutics. Here we discuss problem areas within EAE study designs and provide suggestions for their improvement. This paper is principally directed at investigators new to the field of EAE, although experienced investigators may find useful suggestions herein. PMID:19389303

Automatic design and manufacture of robotic lifeforms.

PubMed

Lipson, H; Pollack, J B

2000-08-31

Biological life is in control of its own means of reproduction, which generally involves complex, autocatalysing chemical reactions. But this autonomy of design and manufacture has not yet been realized artificially. Robots are still laboriously designed and constructed by teams of human engineers, usually at considerable expense. Few robots are available because these costs must be absorbed through mass production, which is justified only for toys, weapons and industrial systems such as automatic teller machines. Here we report the results of a combined computational and experimental approach in which simple electromechanical systems are evolved through simulations from basic building blocks (bars, actuators and artificial neurons); the 'fittest' machines (defined by their locomotive ability) are then fabricated robotically using rapid manufacturing technology. We thus achieve autonomy of design and construction using evolution in a 'limited universe' physical simulation coupled to automatic fabrication.

Situational Interest in Engineering Design Activities

NASA Astrophysics Data System (ADS)

Bonderup Dohn, Niels

2013-08-01

The aim of the present mixed-method study was to investigate task-based situational interest of sixth grade students (n = 46), between 12 and 14 years old, during an eight-week engineering design programme in a Science & Technology-class. Students' interests were investigated by means of a descriptive interpretative analysis of qualitative data from classroom observations and informal interviews. The analysis was complemented by a self-report survey to validate findings and determine prevalence. The analysis revealed four main sources of interest: designing inventions, trial-and-error experimentation, achieved functionality of invention, and collaboration. These sources differ in terms of stimuli factors, such as novelty, autonomy (choice), social involvement, self-generation of interest, and task goal orientation. The study shows that design tasks stimulated interest, but only to the extent that students were able to self-regulate their learning strategies.

Implementation of a Care Pathway for Primary Palliative Care in 5 research clusters in Belgium: quasi-experimental study protocol and innovations in data collection (pro-SPINOZA).

PubMed

Leysen, Bert; Van den Eynden, Bart; Gielen, Birgit; Bastiaens, Hilde; Wens, Johan

2015-09-28

Starting with early identification of palliative care patients by general practitioners (GPs), the Care Pathway for Primary Palliative Care (CPPPC) is believed to help primary health care workers to deliver patient- and family-centered care in the last year of life. The care pathway has been pilot-tested, and will now be implemented in 5 Belgian regions: 2 Dutch-speaking regions, 2 French-speaking regions and the bilingual capital region of Brussels. The overall aim of the CPPPC is to provide better quality of primary palliative care, and in the end to reduce the hospital death rate. The aim of this article is to describe the quantitative design and innovative data collection strategy used in the evaluation of this complex intervention. A quasi-experimental stepped wedge cluster design is set up with the 5 regions being 5 non-randomized clusters. The primary outcome is reduced hospital death rate per GPs' patient population. Secondary outcomes are increased death at home and health care consumption patterns suggesting high quality palliative care. Per research cluster, GPs will be recruited via convenience sampling. These GPs -volunteering to be involved will recruit people with reduced life expectancy and their informal care givers. Health care consumption data in the last year of life, available for all deceased people having lived in the research clusters in the study period, will be used for comparison between patient populations of participating GPs and patient populations of non-participating GPs. Description of baseline characteristics of participating GPs and patients and monitoring of the level of involvement by GPs, patients and informal care givers will happen through regular, privacy-secured web-surveys. Web-survey data and health consumption data are linked in a secure way, respecting Belgian privacy laws. To evaluate this complex intervention, a quasi-experimental stepped wedge cluster design has been set up. Context characteristics and involvement level of participants are important parameters in evaluating complex interventions. It is possible to securely link survey data with health consumption data. By appealing to IT solutions we hope to be able to partly reduce respondent burden, a known problem in palliative care research. ClinicalTrials.gov Identifier: NCT02266069.

A new multiresponse optimization approach in combination with a D-Optimal experimental design for the determination of biogenic amines in fish by HPLC-FLD.

PubMed

Herrero, A; Sanllorente, S; Reguera, C; Ortiz, M C; Sarabia, L A

2016-11-16

A new strategy to approach multiresponse optimization in conjunction to a D-optimal design for simultaneously optimizing a large number of experimental factors is proposed. The procedure is applied to the determination of biogenic amines (histamine, putrescine, cadaverine, tyramine, tryptamine, 2-phenylethylamine, spermine and spermidine) in swordfish by HPLC-FLD after extraction with an acid and subsequent derivatization with dansyl chloride. Firstly, the extraction from a solid matrix and the derivatization of the extract are optimized. Ten experimental factors involved in both stages are studied, seven of them at two levels and the remaining at three levels; the use of a D-optimal design leads to optimize the ten experimental variables, significantly reducing by a factor of 67 the experimental effort needed but guaranteeing the quality of the estimates. A model with 19 coefficients, which includes those corresponding to the main effects and two possible interactions, is fitted to the peak area of each amine. Then, the validated models are used to predict the response (peak area) of the 3456 experiments of the complete factorial design. The variability among peak areas ranges from 13.5 for 2-phenylethylamine to 122.5 for spermine, which shows, to a certain extent, the high and different effect of the pretreatment on the responses. Then the percentiles are calculated from the peak areas of each amine. As the experimental conditions are in conflict, the optimal solution for the multiresponse optimization is chosen from among those which have all the responses greater than a certain percentile for all the amines. The developed procedure reaches decision limits down to 2.5 μg L -1 for cadaverine or 497 μg L -1 for histamine in solvent and 0.07 mg kg -1 and 14.81 mg kg -1 in fish (probability of false positive equal to 0.05), respectively. Copyright © 2016 Elsevier B.V. All rights reserved.

Relevance of advanced nuclear fusion research: Breakthroughs and obstructions

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

Coppi, Bruno, E-mail: coppi@mit.edu

2016-03-25

An in depth understanding of the collective modes that can be excited in a wide range of high-energy plasmas is necessary to advance nuclear fusion research in parallel with other fields that include space and astrophysics in particular. Important achievements are shown to have resulted from implementing programs based on this reality, maintaining a tight connection with different areas of investigations. This involves the undertaking of a plurality of experimental approaches aimed at understanding the physics of fusion burning plasmas. At present, the most advanced among these is the Ignitor experiment involving international cooperation, that is designed to investigate burningmore » plasma regimes near ignition for the first time.« less

Development of quantitative radioactive methodologies on paper to determine important lateral-flow immunoassay parameters.

PubMed

Mosley, Garrett L; Nguyen, Phuong; Wu, Benjamin M; Kamei, Daniel T

2016-08-07

The lateral-flow immunoassay (LFA) is a well-established diagnostic technology that has recently seen significant advancements due in part to the rapidly expanding fields of paper diagnostics and paper-fluidics. As LFA-based diagnostics become more complex, it becomes increasingly important to quantitatively determine important parameters during the design and evaluation process. However, current experimental methods for determining these parameters have certain limitations when applied to LFA systems. In this work, we describe our novel methods of combining paper and radioactive measurements to determine nanoprobe molarity, the number of antibodies per nanoprobe, and the forward and reverse rate constants for nanoprobe binding to immobilized target on the LFA test line. Using a model LFA system that detects for the presence of the protein transferrin (Tf), we demonstrate the application of our methods, which involve quantitative experimentation and mathematical modeling. We also compare the results of our rate constant experiments with traditional experiments to demonstrate how our methods more appropriately capture the influence of the LFA environment on the binding interaction. Our novel experimental approaches can therefore more efficiently guide the research process for LFA design, leading to more rapid advancement of the field of paper-based diagnostics.

Doehlert experimental design applied to optimization of light emitting textile structures

NASA Astrophysics Data System (ADS)

Oguz, Yesim; Cochrane, Cedric; Koncar, Vladan; Mordon, Serge R.

2016-07-01

A light emitting fabric (LEF) has been developed for photodynamic therapy (PDT) for the treatment of dermatologic diseases such as Actinic Keratosis (AK). A successful PDT requires homogenous and reproducible light with controlled power and wavelength on the treated skin area. Due to the shape of the human body, traditional PDT with external light sources is unable to deliver homogenous light everywhere on the skin (head vertex, hand, etc.). For better light delivery homogeneity, plastic optical fibers (POFs) have been woven in textile in order to emit laterally the injected light. The previous studies confirmed that the light power could be locally controlled by modifying the radius of POF macro-bendings within the textile structure. The objective of this study is to optimize the distribution of macro-bendings over the LEF surface in order to increase the light intensity (mW/cm2), and to guarantee the best possible light deliver homogeneity over the LEF which are often contradictory. Fifteen experiments have been carried out with Doehlert experimental design involving Response Surface Methodology (RSM). The proposed models are fitted to the experimental data to enable the optimal set up of the warp yarns tensions.

Reflecting on Graphs: Attributes of Graph Choice and Construction Practices in Biology

PubMed Central

Angra, Aakanksha; Gardner, Stephanie M.

2017-01-01

Undergraduate biology education reform aims to engage students in scientific practices such as experimental design, experimentation, and data analysis and communication. Graphs are ubiquitous in the biological sciences, and creating effective graphical representations involves quantitative and disciplinary concepts and skills. Past studies document student difficulties with graphing within the contexts of classroom or national assessments without evaluating student reasoning. Operating under the metarepresentational competence framework, we conducted think-aloud interviews to reveal differences in reasoning and graph quality between undergraduate biology students, graduate students, and professors in a pen-and-paper graphing task. All professors planned and thought about data before graph construction. When reflecting on their graphs, professors and graduate students focused on the function of graphs and experimental design, while most undergraduate students relied on intuition and data provided in the task. Most undergraduate students meticulously plotted all data with scaled axes, while professors and some graduate students transformed the data, aligned the graph with the research question, and reflected on statistics and sample size. Differences in reasoning and approaches taken in graph choice and construction corroborate and extend previous findings and provide rich targets for undergraduate and graduate instruction. PMID:28821538

Statistical power and optimal design in experiments in which samples of participants respond to samples of stimuli.

PubMed

Westfall, Jacob; Kenny, David A; Judd, Charles M

2014-10-01

Researchers designing experiments in which a sample of participants responds to a sample of stimuli are faced with difficult questions about optimal study design. The conventional procedures of statistical power analysis fail to provide appropriate answers to these questions because they are based on statistical models in which stimuli are not assumed to be a source of random variation in the data, models that are inappropriate for experiments involving crossed random factors of participants and stimuli. In this article, we present new methods of power analysis for designs with crossed random factors, and we give detailed, practical guidance to psychology researchers planning experiments in which a sample of participants responds to a sample of stimuli. We extensively examine 5 commonly used experimental designs, describe how to estimate statistical power in each, and provide power analysis results based on a reasonable set of default parameter values. We then develop general conclusions and formulate rules of thumb concerning the optimal design of experiments in which a sample of participants responds to a sample of stimuli. We show that in crossed designs, statistical power typically does not approach unity as the number of participants goes to infinity but instead approaches a maximum attainable power value that is possibly small, depending on the stimulus sample. We also consider the statistical merits of designs involving multiple stimulus blocks. Finally, we provide a simple and flexible Web-based power application to aid researchers in planning studies with samples of stimuli.

The Effect of Visual of a Courseware towards Pre-University Students' Learning in Literature

NASA Astrophysics Data System (ADS)

Masri, Mazyrah; Wan Ahmad, Wan Fatimah; Nordin, Shahrina Md.; Sulaiman, Suziah

This paper highlights the effect of visual of a multimedia courseware, Black Cat Courseware (BC-C), developed for learning literature at a pre-university level in University Teknologi PETRONAS (UTP). The contents of the courseware are based on a Black Cat story which is covered in an English course at the university. The objective of this paper is to evaluate the usability and effectiveness of BC-C. A total of sixty foundation students were involved in the study. Quasi-experimental design was employed, forming two groups: experimental and control groups. The experimental group had to interact with BC-C as part of the learning activities while the control group used the conventional learning methods. The results indicate that the experimental group achieved a statistically significant compared to the control group in understanding the Black Cat story. The study result also proves that the effect of visual increases the students' performances in literature learning at a pre-university level.

Studies on the Parametric Effects of Plasma Arc Welding of 2205 Duplex Stainless Steel

NASA Astrophysics Data System (ADS)

Selva Bharathi, R.; Siva Shanmugam, N.; Murali Kannan, R.; Arungalai Vendan, S.

2018-03-01

This research study attempts to create an optimized parametric window by employing Taguchi algorithm for Plasma Arc Welding (PAW) of 2 mm thick 2205 duplex stainless steel. The parameters considered for experimentation and optimization are the welding current, welding speed and pilot arc length respectively. The experimentation involves the parameters variation and subsequently recording the depth of penetration and bead width. Welding current of 60-70 A, welding speed of 250-300 mm/min and pilot arc length of 1-2 mm are the range between which the parameters are varied. Design of experiments is used for the experimental trials. Back propagation neural network, Genetic algorithm and Taguchi techniques are used for predicting the bead width, depth of penetration and validated with experimentally achieved results which were in good agreement. Additionally, micro-structural characterizations are carried out to examine the weld quality. The extrapolation of these optimized parametric values yield enhanced weld strength with cost and time reduction.

Utilization of variation theory in the classroom: Effect on students' algebraic achievement and motivation

NASA Astrophysics Data System (ADS)

Jing, Ting Jing; Tarmizi, Rohani Ahmad; Bakar, Kamariah Abu; Aralas, Dalia

2017-01-01

This study investigates the effect of utilizing Variation Theory Based Strategy on students' algebraic achievement and motivation in learning algebra. The study used quasi-experimental non-equivalent control group research design and involved 56 Form Two (Secondary Two) students in two classes (28 in experimental group, 28 in control group) in Malaysia The first class of students went through algebra class taught with Variation Theory Based Strategy (VTBS) while the second class of students experienced conventional teaching strategy. The instruments used for the study were a 24-item Algebra Test and 36-item Instructional Materials Motivation Survey. Result from analysis of Covariance indicated that experimental group students achieved significantly better test scores than control group. Result of Multivariate Analysis of Variance also shows evidences of significant effect of VTBS on experimental students' overall motivation in all the five subscales; attention, relevance, confidence, and satisfaction. These results suggested the utilization of VTBS would improve students' learning in algebra.

Experimental feasibility of investigating acoustic waves in Couette flow with entropy and pressure gradients

NASA Technical Reports Server (NTRS)

Parrott, Tony L.; Zorumski, William E.; Rawls, John W., Jr.

1990-01-01

The feasibility is discussed for an experimental program for studying the behavior of acoustic wave propagation in the presence of strong gradients of pressure, temperature, and flow. Theory suggests that gradients effects can be experimentally observed as resonant frequency shifts and mode shape changes in a waveguide. A convenient experimental geometry for such experiments is the annular region between two co-rotating cylinders. Radial temperature gradients in a spinning annulus can be generated by differentially heating the two cylinders via electromagnetic induction. Radial pressure gradients can be controlled by varying the cylinder spin rates. Present technology appears adequate to construct an apparatus to allow independent control of temperature and pressure gradients. A complicating feature of a more advanced experiment, involving flow gradients, is the requirement for independently controlled cylinder spin rates. Also, the boundary condition at annulus terminations must be such that flow gradients are minimally disturbed. The design and construction of an advanced apparatus to include flow gradients will require additional technology development.

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

Noe, F; Diadone, Isabella; Lollmann, Marc

There is a gap between kinetic experiment and simulation in their views of the dynamics of complex biomolecular systems. Whereas experiments typically reveal only a few readily discernible exponential relaxations, simulations often indicate complex multistate behavior. Here, a theoretical framework is presented that reconciles these two approaches. The central concept is dynamical fingerprints which contain peaks at the time scales of the dynamical processes involved with amplitudes determined by the experimental observable. Fingerprints can be generated from both experimental and simulation data, and their comparison by matching peaks permits assignment of structural changes present in the simulation to experimentally observedmore » relaxation processes. The approach is applied here to a test case interpreting single molecule fluorescence correlation spectroscopy experiments on a set of fluorescent peptides with molecular dynamics simulations. The peptides exhibit complex kinetics shown to be consistent with the apparent simplicity of the experimental data. Moreover, the fingerprint approach can be used to design new experiments with site-specific labels that optimally probe specific dynamical processes in the molecule under investigation.« less

Interfacial characterization of flexible hybrid electronics

NASA Astrophysics Data System (ADS)

Najafian, Sara; Amirkhizi, Alireza V.; Stapleton, Scott

2018-03-01

Flexible Hybrid Electronics (FHEs) are the new generation of electronics combining flexible plastic film substrates with electronic devices. Besides the electrical features, design improvements of FHEs depend on the prediction of their mechanical and failure behavior. Debonding of electronic components from the flexible substrate is one of the most common and critical failures of these devices, therefore, the experimental determination of material and interface properties is of great importance in the prediction of failure mechanisms. Traditional interface characterization involves isolated shear and normal mode tests such as the double cantilever beam (DCB) and end notch flexure (ENF) tests. However, due to the thin, flexible nature of the materials and manufacturing restrictions, tests mirroring traditional interface characterization experiments may not always be possible. The ideal goal of this research is to design experiments such that each mode of fracture is isolated. However, due to the complex nonlinear nature of the response and small geometries of FHEs, design of the proper tests to characterize the interface properties can be significantly time and cost consuming. Hence numerical modeling has been implemented to design these novel characterization experiments. This research involves loading case and specimen geometry parametric studies using numerical modeling to design future experiments where either shear or normal fracture modes are dominant. These virtual experiments will provide a foundation for designing similar tests for many different types of flexible electronics and predicting the failure mechanism independent of the specific FHE materials.

Graphical Models for Quasi-Experimental Designs

ERIC Educational Resources Information Center

Kim, Yongnam; Steiner, Peter M.; Hall, Courtney E.; Su, Dan

2016-01-01

Experimental and quasi-experimental designs play a central role in estimating cause-effect relationships in education, psychology, and many other fields of the social and behavioral sciences. This paper presents and discusses the causal graphs of experimental and quasi-experimental designs. For quasi-experimental designs the authors demonstrate…

Development and Design Application of Rigidized Surface Insulation Thermal Protection Systems, Volume 1. [for the space shuttle

NASA Technical Reports Server (NTRS)

1972-01-01

Materials and design technology of the all-silica LI-900 rigid surface insulation (RSI) thermal protection system (TPS) concept for the shuttle spacecraft is presented. All results of contract development efforts are documented. Engineering design and analysis of RSI strain arrestor plate material selections, sizing, and weight studies are reported. A shuttle prototype test panel was designed, analyzed, fabricated, and delivered. Thermophysical and mechanical properties of LI-900 were experimentally established and reported. Environmental tests, including simulations of shuttle loads represented by thermal response, turbulent duct, convective cycling, and chemical tolerance tests are described and results reported. Descriptions of material test samples and panels fabricated for testing are included. Descriptions of analytical sizing and design procedures are presented in a manner formulated to allow competent engineering organizations to perform rational design studies. Results of parametric studies involving material and system variables are reported. Material performance and design data are also delineated.

Structural Characterization of the Putative Cholinergic Binding Region alpha(179-201) of the Nicotinic Acetylcholine Receptor. Part 1. Review and Experimental Design.

DTIC Science & Technology

1993-04-01

SUBJCT TERMS .. 15. NUMBER OF PAGES Nicotinic acetylcholine receptor FTIR 21 Vibrational spectroscopy Cholinergic 16. PRICE COOE Resonance raman 17...Wilson et al 1955). FMR spectroscopy measures the absorbance of infra-red rad iation, where as Raman spectroscopy measures inelastic scattering of...frequency is domrunated by that chromophore, then Raman scattering involving vibrations localized in that chromophore will be sharply enhanced(Cantor and

Losartan Administration Reduces Fibrosis but Hinders Functional Recovery after Volumetric Muscle Loss Injury

DTIC Science & Technology

2014-09-25

therapy. Pre - viously, losartan has been successfully used to reduce fibrosis and improve both muscle regeneration and function in several models of...efficacy of losartan has not yet been tested in a VML injury model. VML injury involves a substantial loss of muscle tissue that does not regenerate by...fibrosis development after VML injury in the rat tibialis anterior (TA) muscle. METHODS Experimental Design Male Lewis rats with VML were provided access

CVT/GPL phase 3 integrated testing

NASA Technical Reports Server (NTRS)

Shurney, R. E.; Cantrell, E.; Maybee, G.; Schmitt, S.

1975-01-01

The hardware for 20 candidate shuttle program life sciences experiments was installed in the GPL and experiments were conducted during a 5-day simulated mission. The experiments involved humans, primates, rats, chickens, and marigold plants. All experiments were completed to the satisfaction of the experimenters. In addition to the scientific data gathered for each experiment, information was obtained concerning experiment hardware design and integration, experiment procedures, GPL support systems, and test operations. The results of the integrated tests are presented.

Isotherm Modelling, Kinetic Study and Optimization of Batch Parameters Using Response Surface Methodology for Effective Removal of Cr(VI) Using Fungal Biomass

PubMed Central

Chidambaram, Ramalingam

2015-01-01

Biosorption is a promising alternative method to replace the existing conventional technique for Cr(VI) removal from the industrial effluent. In the present experimental design, the removal of Cr(VI) from the aqueous solution was studied by Aspergillus niger MSR4 under different environmental conditions in the batch systems. The optimum conditions of biosorption were determined by investigating pH (2.0) and temperature (27°C). The effects of parameters such as biomass dosage (g/L), initial Cr(VI) concentration (mg/L) and contact time (min) on Cr(VI) biosorption were analyzed using a three parameter Box–Behnken design (BBD). The experimental data well fitted to the Langmuir isotherm, in comparison to the other isotherm models tested. The results of the D-R isotherm model suggested that a chemical ion-exchange mechanism was involved in the biosorption process. The biosorption process followed the pseudo-second-order kinetic model, which indicates that the rate limiting step is chemisorption process. Fourier transform infrared (FT-IR) spectroscopic studies revealed the possible involvement of functional groups, such as hydroxyl, carboxyl, amino and carbonyl group in the biosorption process. The thermodynamic parameters for Cr(VI) biosorption were also calculated, and the negative ∆Gº values indicated the spontaneous nature of biosorption process. PMID:25786227

Development of achiral and chiral 2D HPLC methods for analysis of albendazole metabolites in microsomal fractions using multivariate analysis for the in vitro metabolism.

PubMed

Belaz, Kátia Roberta A; Pereira-Filho, Edenir Rodrigues; Oliveira, Regina V

2013-08-01

In this work, the development of two multidimensional liquid chromatography methods coupled to a fluorescence detector is described for direct analysis of microsomal fractions obtained from rat livers. The chiral multidimensional method was then applied for the optimization of the in vitro metabolism of albendazole by experimental design. Albendazole was selected as a model drug because of its anthelmintics properties and recent potential for cancer treatment. The development of two fully automated achiral-chiral and chiral-chiral high performance liquid chromatography (HPLC) methods for the determination of albendazole (ABZ) and its metabolites albendazole sulphoxide (ABZ-SO), albendazole sulphone (ABZ-SO2) and albendazole 2-aminosulphone (ABZ-SO2NH2) in microsomal fractions are described. These methods involve the use of a phenyl (RAM-phenyl-BSA) or octyl (RAM-C8-BSA) restricted access media bovine serum albumin column for the sample clean-up, followed by an achiral phenyl column (15.0×0.46cmI.D.) or a chiral amylose tris(3,5-dimethylphenylcarbamate) column (15.0×0.46cmI.D.). The chiral 2D HPLC method was applied to the development of a compromise condition for the in vitro metabolism of ABZ by means of experimental design involving multivariate analysis. Copyright © 2013 Elsevier B.V. All rights reserved.

A Guide for the Design of Pre-clinical Studies on Sex Differences in Metabolism.

PubMed

Mauvais-Jarvis, Franck; Arnold, Arthur P; Reue, Karen

2017-06-06

In animal models, the physiological systems involved in metabolic homeostasis exhibit a sex difference. Investigators often use male rodents because they show metabolic disease better than females. Thus, females are not used precisely because of an acknowledged sex difference that represents an opportunity to understand novel factors reducing metabolic disease more in one sex than the other. The National Institutes of Health (NIH) mandate to consider sex as a biological variable in preclinical research places new demands on investigators and peer reviewers who often lack expertise in model systems and experimental paradigms used in the study of sex differences. This Perspective discusses experimental design and interpretation in studies addressing the mechanisms of sex differences in metabolic homeostasis and disease, using animal models and cells. We also highlight current limitations in research tools and attitudes that threaten to delay progress in studies of sex differences in basic animal research. Copyright © 2017 Elsevier Inc. All rights reserved.

Social cohesion through football: a quasi-experimental mixed methods design to evaluate a complex health promotion program

PubMed Central

2010-01-01

Social isolation and disengagement fragments local communities. Evidence indicates that refugee families are highly vulnerable to social isolation in their countries of resettlement. Research to identify approaches to best address this is needed. Football United is a program that aims to foster social inclusion and cohesion in areas with high refugee settlement in New South Wales, Australia, through skills and leadership development, mentoring, and the creation of links with local community and corporate leaders and organisations. The Social Cohesion through Football study's broad goal is to examine the implementation of a complex health promotion program, and to analyse the processes involved in program implementation. The study will consider program impact on individual health and wellbeing, social inclusion and cohesion, as well as analyse how the program by necessity interacts and adapts to context during implementation, a concept we refer to as plasticity. The proposed study will be the first prospective cohort impact study to our knowledge to assess the impact of a comprehensive integrated program using football as a vehicle for fostering social inclusion and cohesion in communities with high refugee settlement. Methods/design A quasi-experimental cohort study design with treatment partitioning involving four study sites. The study employs a 'dose response' model, comparing those with no involvement in the Football United program with those with lower or higher levels of participation. A range of qualitative and quantitative measures will be used in the study. Study participants' emotional well being, resilience, ethnic identity and other group orientation, feelings of social inclusion and belonging will be measured using a survey instrument complemented by relevant data drawn from in-depth interviews, self reporting measures and participant observation. The views of key informants from the program and the wider community will also be solicited. Discussion The complexity of the Football United program poses challenges for measurement, and requires the study design to be responsive to the dynamic nature of the program and context. Assessment of change is needed at multiple levels, drawing on mixed methods and multidisciplinary approaches in implementation and evaluation. Attention to these challenges has underpinned the design and methods in the Social Cohesion through Football study, which will use a unique and innovative combination of measures that have not been applied together previously in social inclusion/cohesion and sport and social inclusion/cohesion program research. PMID:20920361

Revealing the Effects of the Herbal Pair of Euphorbia kansui and Glycyrrhiza on Hepatocellular Carcinoma Ascites with Integrating Network Target Analysis and Experimental Validation

PubMed Central

Zhang, Yanqiong; Lin, Ya; Zhao, Haiyu; Guo, Qiuyan; Yan, Chen; Lin, Na

2016-01-01

Although the herbal pair of Euphorbia kansui (GS) and Glycyrrhiza (GC) is one of the so-called "eighteen antagonistic medicaments" in Chinese medicinal literature, it is prescribed in a classic Traditional Chinese Medicine (TCM) formula Gansui-Banxia-Tang for cancerous ascites, suggesting that GS and GC may exhibit synergistic or antagonistic effects in different combination designs. Here, we modeled the effects of GS/GC combination with a target interaction network and clarified the associations between the network topologies involving the drug targets and the drug combination effects. Moreover, the "edge-betweenness" values, which is defined as the frequency with which edges are placed on the shortest paths between all pairs of modules in network, were calculated, and the ADRB1-PIK3CG interaction exhibited the greatest edge-betweenness value, suggesting its crucial role in connecting the other edges in the network. Because ADRB1 and PIK3CG were putative targets of GS and GC, respectively, and both had functional interactions with AVPR2 approved as known therapeutic target for ascites, we proposed that the ADRB1-PIK3CG-AVPR2 signal axis might be involved in the effects of the GS-GC combination on ascites. This proposal was further experimentally validated in a H22 hepatocellular carcinoma (HCC) ascites model. Collectively, this systems-level investigation integrated drug target prediction and network analysis to reveal the combination principles of the herbal pair of GS and GC. Experimental validation in an in vivo system provided convincing evidence that different combination designs of GS and GC might result in synergistic or antagonistic effects on HCC ascites that might be partially related to their regulation of the ADRB1-PIK3CG-AVPR2 signal axis. PMID:27143956

Understanding healthcare innovation systems: the Stockholm region case.

PubMed

Larisch, Lisa-Marie; Amer-Wåhlin, Isis; Hidefjäll, Patrik

2016-11-21

Purpose There is an increasing interest in understanding how innovation processes can address current challenges in healthcare. The purpose of this paper is to analyze the wider socio-economic context and conditions for such innovation processes in the Stockholm region, using the functional dynamics approach to innovation systems (ISs). Design/methodology/approach The analysis is based on triangulation using data from 16 in-depth interviews, two workshops, and additional documents. Using the functional dynamics approach, critical structural and functional components of the healthcare IS were analyzed. Findings The analysis revealed several mechanisms blocking innovation processes such as fragmentation, lack of clear leadership, as well as insufficient involvement of patients and healthcare professionals. Furthermore, innovation is expected to occur linearly as a result of research. Restrictive rules for collaboration with industry, reimbursement, and procurement mechanisms limit entrepreneurial experimentation, commercialization, and spread of innovations. Research limitations/implications In this study, the authors analyzed how certain functions of the functional dynamics approach to ISs related to each other. The authors grouped knowledge creation, resource mobilization, and legitimacy as they jointly constitute conditions for needs articulation and entrepreneurial experimentation. The economic effects of entrepreneurial experimentation and needs articulation are mainly determined by the stage of market formation and existence of positive externalities. Social implications Stronger user involvement; a joint innovation strategy for healthcare, academia, and industry; and institutional reform are necessary to remove blocking mechanisms that today prevent innovation from occurring. Originality/value This study is the first to provide an analysis of the system of innovation in healthcare using a functional dynamics approach, which has evolved as a tool for public policy making. A better understanding of ISs in general, and in healthcare in particular, may provide the basis for designing and evaluating innovation policy.

Challenging Density Functional Theory Calculations with Hemes and Porphyrins.

PubMed

de Visser, Sam P; Stillman, Martin J

2016-04-07

In this paper we review recent advances in computational chemistry and specifically focus on the chemical description of heme proteins and synthetic porphyrins that act as both mimics of natural processes and technological uses. These are challenging biochemical systems involved in electron transfer as well as biocatalysis processes. In recent years computational tools have improved considerably and now can reproduce experimental spectroscopic and reactivity studies within a reasonable error margin (several kcal·mol(-1)). This paper gives recent examples from our groups, where we investigated heme and synthetic metal-porphyrin systems. The four case studies highlight how computational modelling can correctly reproduce experimental product distributions, predicted reactivity trends and guide interpretation of electronic structures of complex systems. The case studies focus on the calculations of a variety of spectroscopic features of porphyrins and show how computational modelling gives important insight that explains the experimental spectra and can lead to the design of porphyrins with tuned properties.

Flexible energy harvesting from hard piezoelectric beams

NASA Astrophysics Data System (ADS)

Delnavaz, Aidin; Voix, Jérémie

2016-11-01

This paper presents design, multiphysics finite element modeling and experimental validation of a new miniaturized PZT generator that integrates a bulk piezoelectric ceramic onto a flexible platform for energy harvesting from the human body pressing force. In spite of its flexibility, the mechanical structure of the proposed device is simple to fabricate and efficient for the energy conversion. The finite element model involves both mechanical and piezoelectric parts of the device coupled with the electrical circuit model. The energy harvester prototype was fabricated and tested under the low frequency periodic pressing force during 10 seconds. The experimental results show that several nano joules of electrical energy is stored in a capacitor that is quite significant given the size of the device. The finite element model is validated by observing a good agreement between experimental and simulation results. the validated model could be used for optimizing the device for energy harvesting from earcanal deformations.

High energy beam impact tests on a LHC tertiary collimator at the CERN high-radiation to materials facility

NASA Astrophysics Data System (ADS)

Cauchi, Marija; Aberle, O.; Assmann, R. W.; Bertarelli, A.; Carra, F.; Cornelis, K.; Dallocchio, A.; Deboy, D.; Lari, L.; Redaelli, S.; Rossi, A.; Salvachua, B.; Mollicone, P.; Sammut, N.

2014-02-01

The correct functioning of a collimation system is crucial to safely operate highly energetic particle accelerators, such as the Large Hadron Collider (LHC). The requirements to handle high intensity beams can be demanding. In this respect, investigating the consequences of LHC particle beams hitting tertiary collimators (TCTs) in the experimental regions is a fundamental issue for machine protection. An experimental test was designed to investigate the robustness and effects of beam accidents on a fully assembled collimator, based on accident scenarios in the LHC. This experiment, carried out at the CERN High-Radiation to Materials (HiRadMat) facility, involved 440 GeV proton beam impacts of different intensities on the jaws of a horizontal TCT. This paper presents the experimental setup and the preliminary results obtained, together with some first outcomes from visual inspection and a comparison of such results with numerical simulations.

LBE water interaction in sub-critical reactors: First experimental and modelling results

NASA Astrophysics Data System (ADS)

Ciampichetti, A.; Agostini, P.; Benamati, G.; Bandini, G.; Pellini, D.; Forgione, N.; Oriolo, F.; Ambrosini, W.

2008-06-01

This paper concerns the study of the phenomena involved in the interaction between LBE and pressurised water which could occur in some hypothetical accidents in accelerator driven system type reactors. The LIFUS 5 facility was designed and built at ENEA-Brasimone to reproduce this kind of interaction in a wide range of conditions. The first test of the experimental program was carried out injecting water at 70 bar and 235 °C in a reaction vessel containing LBE at 1 bar and 350 °C. A pressurisation up to 80 bar was observed in the test section during the considered transient. The SIMMER III code was used to simulate the performed test. The calculated data agree in a satisfactory way with the experimental results giving confidence in the possibility to use this code for safety analyses of heavy liquid metal cooled reactors.

Experimental investigation of a four-qubit linear-optical quantum logic circuit

PubMed Central

Stárek, R.; Mičuda, M.; Miková, M.; Straka, I.; Dušek, M.; Ježek, M.; Fiurášek, J.

2016-01-01

We experimentally demonstrate and characterize a four-qubit linear-optical quantum logic circuit. Our robust and versatile scheme exploits encoding of two qubits into polarization and path degrees of single photons and involves two crossed inherently stable interferometers. This approach allows us to design a complex quantum logic circuit that combines a genuine four-qubit C3Z gate and several two-qubit and single-qubit gates. The C3Z gate introduces a sign flip if and only if all four qubits are in the computational state |1〉. We verify high-fidelity performance of this central four-qubit gate using Hofmann bounds on quantum gate fidelity and Monte Carlo fidelity sampling. We also experimentally demonstrate that the quantum logic circuit can generate genuine multipartite entanglement and we certify the entanglement with the use of suitably tailored entanglement witnesses. PMID:27647176

Experimental Study on the Precise Orbit Determination of the BeiDou Navigation Satellite System

PubMed Central

He, Lina; Ge, Maorong; Wang, Jiexian; Wickert, Jens; Schuh, Harald

2013-01-01

The regional service of the Chinese BeiDou satellite navigation system is now in operation with a constellation including five Geostationary Earth Orbit satellites (GEO), five Inclined Geosynchronous Orbit (IGSO) satellites and four Medium Earth Orbit (MEO) satellites. Besides the standard positioning service with positioning accuracy of about 10 m, both precise relative positioning and precise point positioning are already demonstrated. As is well known, precise orbit and clock determination is essential in enhancing precise positioning services. To improve the satellite orbits of the BeiDou regional system, we concentrate on the impact of the tracking geometry and the involvement of MEOs, and on the effect of integer ambiguity resolution as well. About seven weeks of data collected at the BeiDou Experimental Test Service (BETS) network is employed in this experimental study. Several tracking scenarios are defined, various processing schemata are designed and carried out; and then, the estimates are compared and analyzed in detail. The results show that GEO orbits, especially the along-track component, can be significantly improved by extending the tracking network in China along longitude direction, whereas IGSOs gain more improvement if the tracking network extends in latitude. The involvement of MEOs and ambiguity-fixing also make the orbits better. PMID:23529116

Experimental study on the precise orbit determination of the BeiDou navigation satellite system.

PubMed

He, Lina; Ge, Maorong; Wang, Jiexian; Wickert, Jens; Schuh, Harald

2013-03-01

The regional service of the Chinese BeiDou satellite navigation system is now in operation with a constellation including five Geostationary Earth Orbit satellites (GEO), five Inclined Geosynchronous Orbit (IGSO) satellites and four Medium Earth Orbit (MEO) satellites. Besides the standard positioning service with positioning accuracy of about 10 m, both precise relative positioning and precise point positioning are already demonstrated. As is well known, precise orbit and clock determination is essential in enhancing precise positioning services. To improve the satellite orbits of the BeiDou regional system, we concentrate on the impact of the tracking geometry and the involvement of MEOs, and on the effect of integer ambiguity resolution as well. About seven weeks of data collected at the BeiDou Experimental Test Service (BETS) network is employed in this experimental study. Several tracking scenarios are defined, various processing schemata are designed and carried out; and then, the estimates are compared and analyzed in detail. The results show that GEO orbits, especially the along-track component, can be significantly improved by extending the tracking network in China along longitude direction, whereas IGSOs gain more improvement if the tracking network extends in latitude. The involvement of MEOs and ambiguity-fixing also make the orbits better.

Inflammation as a therapeutic target in myocardial infarction: learning from past failures to meet future challenges

PubMed Central

Saxena, Amit; Russo, Ilaria; Frangogiannis, Nikolaos G

2015-01-01

In the infarcted myocardium, necrotic cardiomyocytes release danger signals, activating an intense inflammatory response. Inflammatory pathways play a crucial role in regulation of a wide range of cellular processes involved in injury, repair and remodeling of the infarcted heart. Pro-inflammatory cytokines, such as tumor necrosis factor-a and interleukin (IL)-1, are markedly upregulated in the infarcted myocardium and promote adhesive interactions between endothelial cells and leukocytes, by stimulating chemokine and adhesion molecule expression. Distinct chemokine/chemokine receptor pairs are implicated in recruitment of various leukocyte subpopulations in the infarcted myocardium. Over the last 30 years, extensive experimental work has explored the role of inflammatory signals and the contributions of leukocyte subpopulations, in myocardial infarction. Robust evidence derived from experimental models of myocardial infarction has identified inflammatory targets that may attenuate cardiomyocyte injury, or protect from adverse remodeling. Unfortunately, attempts to translate the promising experimental findings to clinical therapy have failed. This review manuscript discusses the biology of the inflammatory response following myocardial infarction, attempts to identify the causes for the translational failures of the past, and proposes promising new therapeutic directions. Because of their potential involvement in injurious, reparative and regenerative responses, inflammatory cells may hold the key for design of new therapies in myocardial infarction. PMID:26241027

[Optimization of ultrasonic-assisted extraction of total flavonoids from leaves of the Artocarpus heterophyllus by response surface methodology].

PubMed

Wang, Hong-wu; Liu, Yan-qing; Wang, Yuan-hong

2011-07-01

To investigate the ultrasonic-assisted extract on of total flavonoids from leaves of the Artocarpus heterophyllus. Investigated the effects of ethanol concentration, extraction time, and liquid-solid ratio on flavonoids yield. A 17-run response surface design involving three factors at three levels was generated by the Design-Expert software and experimental data obtained were subjected to quadratic regression analysis to create a mathematical model describing flavonoids extraction. The optimum ultrasonic assisted extraction conditions were: ethanol volume fraction 69.4% and liquid-solid ratio of 22.6:1 for 32 min. Under these optimized conditions, the yield of flavonoids was 7.55 mg/g. The Box-Behnken design and response surface analysis can well optimize the ultrasonic-assisted extraction of total flavonoids from Artocarpus heterophyllus.

Neural architecture design based on extreme learning machine.

PubMed

Bueno-Crespo, Andrés; García-Laencina, Pedro J; Sancho-Gómez, José-Luis

2013-12-01

Selection of the optimal neural architecture to solve a pattern classification problem entails to choose the relevant input units, the number of hidden neurons and its corresponding interconnection weights. This problem has been widely studied in many research works but their solutions usually involve excessive computational cost in most of the problems and they do not provide a unique solution. This paper proposes a new technique to efficiently design the MultiLayer Perceptron (MLP) architecture for classification using the Extreme Learning Machine (ELM) algorithm. The proposed method provides a high generalization capability and a unique solution for the architecture design. Moreover, the selected final network only retains those input connections that are relevant for the classification task. Experimental results show these advantages. Copyright © 2013 Elsevier Ltd. All rights reserved.

Maximizing Macromolecule Crystal Size for Neutron Diffraction Experiments

NASA Technical Reports Server (NTRS)

Judge, R. A.; Kephart, R.; Leardi, R.; Myles, D. A.; Snell, E. H.; vanderWoerd, M.; Curreri, Peter A. (Technical Monitor)

2002-01-01

A challenge in neutron diffraction experiments is growing large (greater than 1 cu mm) macromolecule crystals. In taking up this challenge we have used statistical experiment design techniques to quickly identify crystallization conditions under which the largest crystals grow. These techniques provide the maximum information for minimal experimental effort, allowing optimal screening of crystallization variables in a simple experimental matrix, using the minimum amount of sample. Analysis of the results quickly tells the investigator what conditions are the most important for the crystallization. These can then be used to maximize the crystallization results in terms of reducing crystal numbers and providing large crystals of suitable habit. We have used these techniques to grow large crystals of Glucose isomerase. Glucose isomerase is an industrial enzyme used extensively in the food industry for the conversion of glucose to fructose. The aim of this study is the elucidation of the enzymatic mechanism at the molecular level. The accurate determination of hydrogen positions, which is critical for this, is a requirement that neutron diffraction is uniquely suited for. Preliminary neutron diffraction experiments with these crystals conducted at the Institute Laue-Langevin (Grenoble, France) reveal diffraction to beyond 2.5 angstrom. Macromolecular crystal growth is a process involving many parameters, and statistical experimental design is naturally suited to this field. These techniques are sample independent and provide an experimental strategy to maximize crystal volume and habit for neutron diffraction studies.

fMRI reliability: influences of task and experimental design.

PubMed

Bennett, Craig M; Miller, Michael B

2013-12-01

As scientists, it is imperative that we understand not only the power of our research tools to yield results, but also their ability to obtain similar results over time. This study is an investigation into how common decisions made during the design and analysis of a functional magnetic resonance imaging (fMRI) study can influence the reliability of the statistical results. To that end, we gathered back-to-back test-retest fMRI data during an experiment involving multiple cognitive tasks (episodic recognition and two-back working memory) and multiple fMRI experimental designs (block, event-related genetic sequence, and event-related m-sequence). Using these data, we were able to investigate the relative influences of task, design, statistical contrast (task vs. rest, target vs. nontarget), and statistical thresholding (unthresholded, thresholded) on fMRI reliability, as measured by the intraclass correlation (ICC) coefficient. We also utilized data from a second study to investigate test-retest reliability after an extended, six-month interval. We found that all of the factors above were statistically significant, but that they had varying levels of influence on the observed ICC values. We also found that these factors could interact, increasing or decreasing the relative reliability of certain Task × Design combinations. The results suggest that fMRI reliability is a complex construct whose value may be increased or decreased by specific combinations of factors.

Designing Awe in Virtual Reality: An Experimental Study.

PubMed

Chirico, Alice; Ferrise, Francesco; Cordella, Lorenzo; Gaggioli, Andrea

2017-01-01

Awe is a little-studied emotion with a great transformative potential. Therefore, the interest toward the study of awe's underlying mechanisms has been increased. Specifically, researchers have been interested in how to reproduce intense feelings of awe within laboratory conditions. It has been proposed that the use of virtual reality (VR) could be an effective way to induce awe in controlled experimental settings, thanks to its ability of providing participants with a sense of "presence," that is, the subjective feeling of being displaced in another physical or imaginary place. However, the potential of VR as awe-inducing medium has not been fully tested yet. In the present study, we provided an evidence-based design and a validation of four immersive virtual environments (VEs) involving 36 participants in a within-subject design. Of these, three VEs were designed to induce awe, whereas the fourth VE was targeted as an emotionally neutral stimulus. Participants self-reported the extent to which they felt awe, general affect and sense of presence related to each environment. As expected, results showed that awe-VEs could induce significantly higher levels of awe and presence as compared to the neutral VE. Furthermore, these VEs induced significantly more positive than negative affect. These findings supported the potential of immersive VR for inducing awe and provide useful indications for the design of awe-inspiring virtual environments.

Performance metric comparison study for non-magnetic bi-stable energy harvesters

NASA Astrophysics Data System (ADS)

Udani, Janav P.; Wrigley, Cailin; Arrieta, Andres F.

2017-04-01

Energy harvesting employing non-linear systems offers considerable advantages over linear systems given the broadband resonant response which is favorable for applications involving diverse input vibrations. In this respect, the rich dynamics of bi-stable systems present a promising means for harvesting vibrational energy from ambient sources. Harvesters deriving their bi-stability from thermally induced stresses as opposed to magnetic forces are receiving significant attention as it reduces the need for ancillary components and allows for bio- compatible constructions. However, the design of these bi-stable harvesters still requires further optimization to completely exploit the dynamic behavior of these systems. This study presents a comparison of the harvesting capabilities of non-magnetic, bi-stable composite laminates under variations in the design parameters as evaluated utilizing established power metrics. Energy output characteristics of two bi-stable composite laminate plates with a piezoelectric patch bonded on the top surface are experimentally investigated for variations in the thickness ratio and inertial mass positions for multiple load conditions. A particular design configuration is found to perform better over the entire range of testing conditions which include single and multiple frequency excitation, thus indicating that design optimization over the geometry of the harvester yields robust performance. The experimental analysis further highlights the need for appropriate design guidelines for optimization and holistic performance metrics to account for the range of operational conditions.

Autonomous entropy-based intelligent experimental design

NASA Astrophysics Data System (ADS)

Malakar, Nabin Kumar

2011-07-01

The aim of this thesis is to explore the application of probability and information theory in experimental design, and to do so in a way that combines what we know about inference and inquiry in a comprehensive and consistent manner. Present day scientific frontiers involve data collection at an ever-increasing rate. This requires that we find a way to collect the most relevant data in an automated fashion. By following the logic of the scientific method, we couple an inference engine with an inquiry engine to automate the iterative process of scientific learning. The inference engine involves Bayesian machine learning techniques to estimate model parameters based upon both prior information and previously collected data, while the inquiry engine implements data-driven exploration. By choosing an experiment whose distribution of expected results has the maximum entropy, the inquiry engine selects the experiment that maximizes the expected information gain. The coupled inference and inquiry engines constitute an autonomous learning method for scientific exploration. We apply it to a robotic arm to demonstrate the efficacy of the method. Optimizing inquiry involves searching for an experiment that promises, on average, to be maximally informative. If the set of potential experiments is described by many parameters, the search involves a high-dimensional entropy space. In such cases, a brute force search method will be slow and computationally expensive. We develop an entropy-based search algorithm, called nested entropy sampling, to select the most informative experiment. This helps to reduce the number of computations necessary to find the optimal experiment. We also extended the method of maximizing entropy, and developed a method of maximizing joint entropy so that it could be used as a principle of collaboration between two robots. This is a major achievement of this thesis, as it allows the information-based collaboration between two robotic units towards a same goal in an automated fashion.

Hybrid power system intelligent operation and protection involving distributed architectures and pulsed loads

NASA Astrophysics Data System (ADS)

Mohamed, Ahmed

Efficient and reliable techniques for power delivery and utilization are needed to account for the increased penetration of renewable energy sources in electric power systems. Such methods are also required for current and future demands of plug-in electric vehicles and high-power electronic loads. Distributed control and optimal power network architectures will lead to viable solutions to the energy management issue with high level of reliability and security. This dissertation is aimed at developing and verifying new techniques for distributed control by deploying DC microgrids, involving distributed renewable generation and energy storage, through the operating AC power system. To achieve the findings of this dissertation, an energy system architecture was developed involving AC and DC networks, both with distributed generations and demands. The various components of the DC microgrid were designed and built including DC-DC converters, voltage source inverters (VSI) and AC-DC rectifiers featuring novel designs developed by the candidate. New control techniques were developed and implemented to maximize the operating range of the power conditioning units used for integrating renewable energy into the DC bus. The control and operation of the DC microgrids in the hybrid AC/DC system involve intelligent energy management. Real-time energy management algorithms were developed and experimentally verified. These algorithms are based on intelligent decision-making elements along with an optimization process. This was aimed at enhancing the overall performance of the power system and mitigating the effect of heavy non-linear loads with variable intensity and duration. The developed algorithms were also used for managing the charging/discharging process of plug-in electric vehicle emulators. The protection of the proposed hybrid AC/DC power system was studied. Fault analysis and protection scheme and coordination, in addition to ideas on how to retrofit currently available protection concepts and devices for AC systems in a DC network, were presented. A study was also conducted on the effect of changing the distribution architecture and distributing the storage assets on the various zones of the network on the system's dynamic security and stability. A practical shipboard power system was studied as an example of a hybrid AC/DC power system involving pulsed loads. Generally, the proposed hybrid AC/DC power system, besides most of the ideas, controls and algorithms presented in this dissertation, were experimentally verified at the Smart Grid Testbed, Energy Systems Research Laboratory. All the developments in this dissertation were experimentally verified at the Smart Grid Testbed.

Three-dimensional printing physiology laboratory technology.

PubMed

Sulkin, Matthew S; Widder, Emily; Shao, Connie; Holzem, Katherine M; Gloschat, Christopher; Gutbrod, Sarah R; Efimov, Igor R

2013-12-01

Since its inception in 19th-century Germany, the physiology laboratory has been a complex and expensive research enterprise involving experts in various fields of science and engineering. Physiology research has been critically dependent on cutting-edge technological support of mechanical, electrical, optical, and more recently computer engineers. Evolution of modern experimental equipment is constrained by lack of direct communication between the physiological community and industry producing this equipment. Fortunately, recent advances in open source technologies, including three-dimensional printing, open source hardware and software, present an exciting opportunity to bring the design and development of research instrumentation to the end user, i.e., life scientists. Here we provide an overview on how to develop customized, cost-effective experimental equipment for physiology laboratories.

The strong Bell inequalities: A proposed experimental test

NASA Technical Reports Server (NTRS)

Fry, Edward S.

1994-01-01

All previous experimental tests of Bell inequalities have required additional assumptions. The strong Bell inequalities (i.e. those requiring no additional assumptions) have never been tested. An experiment has been designed that can, for the first time, provide a definitive test of the strong Bell inequalities. Not only will the detector efficiency loophole be closed; but the locality condition will also be rigorously enforced. The experiment involves producing two Hg-199 atoms by a resonant Raman dissociation of a mercury dimer ((199)Hg2) that is in an electronic and nuclear spin singlet state. Bell inequalities can be tested by measuring angular momentum correlations between the spin one-half nuclei of the two Hg-199 atoms. The method used to make these latter measurements will be described.

A practical approach for exploration and modeling of the design space of a bacterial vaccine cultivation process.

PubMed

Streefland, M; Van Herpen, P F G; Van de Waterbeemd, B; Van der Pol, L A; Beuvery, E C; Tramper, J; Martens, D E; Toft, M

2009-10-15

A licensed pharmaceutical process is required to be executed within the validated ranges throughout the lifetime of product manufacturing. Changes to the process, especially for processes involving biological products, usually require the manufacturer to demonstrate that the safety and efficacy of the product remains unchanged by new or additional clinical testing. Recent changes in the regulations for pharmaceutical processing allow broader ranges of process settings to be submitted for regulatory approval, the so-called process design space, which means that a manufacturer can optimize his process within the submitted ranges after the product has entered the market, which allows flexible processes. In this article, the applicability of this concept of the process design space is investigated for the cultivation process step for a vaccine against whooping cough disease. An experimental design (DoE) is applied to investigate the ranges of critical process parameters that still result in a product that meets specifications. The on-line process data, including near infrared spectroscopy, are used to build a descriptive model of the processes used in the experimental design. Finally, the data of all processes are integrated in a multivariate batch monitoring model that represents the investigated process design space. This article demonstrates how the general principles of PAT and process design space can be applied for an undefined biological product such as a whole cell vaccine. The approach chosen for model development described here, allows on line monitoring and control of cultivation batches in order to assure in real time that a process is running within the process design space.

Recommendations for Benchmarking Preclinical Studies of Nanomedicines.

PubMed

Dawidczyk, Charlene M; Russell, Luisa M; Searson, Peter C

2015-10-01

Nanoparticle-based delivery systems provide new opportunities to overcome the limitations associated with traditional small-molecule drug therapy for cancer and to achieve both therapeutic and diagnostic functions in the same platform. Preclinical trials are generally designed to assess therapeutic potential and not to optimize the design of the delivery platform. Consequently, progress in developing design rules for cancer nanomedicines has been slow, hindering progress in the field. Despite the large number of preclinical trials, several factors restrict comparison and benchmarking of different platforms, including variability in experimental design, reporting of results, and the lack of quantitative data. To solve this problem, we review the variables involved in the design of preclinical trials and propose a protocol for benchmarking that we recommend be included in in vivo preclinical studies of drug-delivery platforms for cancer therapy. This strategy will contribute to building the scientific knowledge base that enables development of design rules and accelerates the translation of new technologies. ©2015 American Association for Cancer Research.

Perspective: Recommendations for benchmarking pre-clinical studies of nanomedicines

PubMed Central

Dawidczyk, Charlene M.; Russell, Luisa M.; Searson, Peter C.

2015-01-01

Nanoparticle-based delivery systems provide new opportunities to overcome the limitations associated with traditional small molecule drug therapy for cancer, and to achieve both therapeutic and diagnostic functions in the same platform. Pre-clinical trials are generally designed to assess therapeutic potential and not to optimize the design of the delivery platform. Consequently, progress in developing design rules for cancer nanomedicines has been slow, hindering progress in the field. Despite the large number of pre-clinical trials, several factors restrict comparison and benchmarking of different platforms, including variability in experimental design, reporting of results, and the lack of quantitative data. To solve this problem, we review the variables involved in the design of pre-clinical trials and propose a protocol for benchmarking that we recommend be included in in vivo pre-clinical studies of drug delivery platforms for cancer therapy. This strategy will contribute to building the scientific knowledge base that enables development of design rules and accelerates the translation of new technologies. PMID:26249177

Improving of prospective elementary teachers' reasoning: Learning geometry through mathematical investigation

NASA Astrophysics Data System (ADS)

Sumarna, Nana; Sentryo, Izlan

2017-08-01

This research applies mathematical investigation approach in teaching geometry to improve mathematical reasoning abilities of prospective elementary teachers. Mathematical investigation in this study involved non-routine tasks through a mathematical investigation process, namely through a series of activities as an attribute of mathematical investigation. Developing the ability of mathematical reasoning of research subjects obtained through capability of research subjects in the analysis, generalization, synthesis, justify, and resolve non-routine, which is operationally constructed as an indicator of research and is used as a criterion for measuring the ability of mathematical reasoning. Research design using Quasi-Experimental design. Based on this type, the researchers apply a pre-and posttest design, which is divided into two study groups: control group and the treatment group. The number of research subjects were 111 students consisting of 56 students in the experimental group and 55 students in the control group. The conclusion of this study stated that (1) Investigation of mathematics as an approach to learning is able to give a positive response to the increasing ability of mathematical reasoning, and (2) There is no interaction effect of the factors of learning and prior knowledge of mathematics to the increased ability of mathematical reasoning.

Study of the effects of informational and persuasive messages on the attitudes of high school students toward the use of nuclear energy for electrical production

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

Showers, D.E.

1986-01-01

This investigation assessed the relationship between knowledge about and attitudes toward nuclear energy. The study's purpose was accomplished by attempting to manipulate knowledge about and attitude toward nuclear energy independently. Over two thousand high school students participated in the study. A Non-Equivalent Control Group quasi-experimental design was used involving random assignment by intact groups to treatments. A knowledge treatment was designed to increase student knowledge without affecting attitudes. An attitude treatment was designed to change attitudes without changing knowledge, and a control treatment was employed for comparison to the experimental treatments. Each treatment consisted of a videotape with a viewingmore » guide and a homework assignment. The Nuclear Energy Assessment Battery was used as a pretest, post-test, and retention test. Males scored significantly higher in knowledge and positive attitudes, but no interaction between gender and treatment was found. The study concluded that (1) there is a correlation between nuclear knowledge and attitudes, (2) knowledge about nuclear energy can be changed without affecting attitude and attitude can be changed without affecting knowledge, and (3) students show differences and attitude based on gender.« less

Seven common mistakes in population genetics and how to avoid them.

PubMed

Meirmans, Patrick G

2015-07-01

As the data resulting from modern genotyping tools are astoundingly complex, genotyping studies require great care in the sampling design, genotyping, data analysis and interpretation. Such care is necessary because, with data sets containing thousands of loci, small biases can easily become strongly significant patterns. Such biases may already be present in routine tasks that are present in almost every genotyping study. Here, I discuss seven common mistakes that can be frequently encountered in the genotyping literature: (i) giving more attention to genotyping than to sampling, (ii) failing to perform or report experimental randomization in the laboratory, (iii) equating geopolitical borders with biological borders, (iv) testing significance of clustering output, (v) misinterpreting Mantel's r statistic, (vi) only interpreting a single value of k and (vii) forgetting that only a small portion of the genome will be associated with climate. For every of those issues, I give some suggestions how to avoid the mistake. Overall, I argue that genotyping studies would benefit from establishing a more rigorous experimental design, involving proper sampling design, randomization and better distinction of a priori hypotheses and exploratory analyses. © 2015 John Wiley & Sons Ltd.

Airborne Use of Traffic Intent Information in a Distributed Air-Ground Traffic Management Concept: Experiment Design and Preliminary Results

NASA Technical Reports Server (NTRS)

Wing, David J.; Adams, Richard J.; Duley, Jacqueline A.; Legan, Brian M.; Barmore, Bryan E.; Moses, Donald

2001-01-01

A predominant research focus in the free flight community has been on the type of information required on the flight deck to enable pilots to "autonomously" maintain separation from other aircraft. At issue are the relative utility and requirement for information exchange between aircraft regarding the current "state" and/or the "intent" of each aircraft. This paper presents the experimental design and some initial findings of an experimental research study designed to provide insight into the issue of intent information exchange in constrained en-route operations and its effect on pilot decision making and flight performance. Two operational modes for autonomous operations were compared in a piloted simulation. The tactical mode was characterized primarily by the use of state information for conflict detection and resolution and an open-loop means for the pilot to meet operational constraints. The strategic mode involved the combined use of state and intent information, provided the pilot an additional level of alerting, and allowed a closed-loop approach to meeting operational constraints. Potential operational benefits of both modes are illustrated through several scenario case studies. Subjective data results are presented that generally indicate pilot consensus in favor of the strategic mode.

Manganese ore tailing: optimization of acid leaching conditions and recovery of soluble manganese.

PubMed

Santos, Olívia de Souza Heleno; Carvalho, Cornélio de Freitas; Silva, Gilmare Antônia da; Santos, Cláudio Gouvêa Dos

2015-01-01

Manganese recovery from industrial ore processing waste by means of leaching with sulfuric acid was the objective of this study. Experimental conditions were optimized by multivariate experimental design approaches. In order to study the factors affecting leaching, a screening step was used involving a full factorial design with central point for three variables in two levels (2(3)). The three variables studied were leaching time, concentration of sulfuric acid and sample amount. The three factors screened were shown to be relevant and therefore a Doehlert design was applied to determine the best working conditions for leaching and to build the response surface. By applying the best leaching conditions, the concentrations of 12.80 and 13.64 %w/w of manganese for the global sample and for the fraction -44 + 37 μm, respectively, were found. Microbeads of chitosan were tested for removal of leachate acidity and recovering of soluble manganese. Manganese recovery from the leachate was 95.4%. Upon drying the leachate, a solid containing mostly manganese sulfate was obtained, showing that the proposed optimized method is efficient for manganese recovery from ore tailings. Copyright © 2014 Elsevier Ltd. All rights reserved.

Development of a Model for Measuring Scientific Processing Skills Based on Brain-Imaging Technology: Focused on the Experimental Design Process

ERIC Educational Resources Information Center

Lee, Il-Sun; Byeon, Jung-Ho; Kim, Young-shin; Kwon, Yong-Ju

2014-01-01

The purpose of this study was to develop a model for measuring experimental design ability based on functional magnetic resonance imaging (fMRI) during biological inquiry. More specifically, the researchers developed an experimental design task that measures experimental design ability. Using the developed experimental design task, they measured…

A randomized controlled trial of an intervention program to Brazilian mothers who use corporal punishment.

PubMed

Santini, Paolla Magioni; Williams, Lucia C A

2017-09-01

This study evaluated a positive parenting program to Brazilian mothers who used corporal punishment with their children. The intervention was conducted in four agencies serving vulnerable children, and at a home replica laboratory at the University. Mothers who admitted using corporal punishment were randomly assigned between experimental (n=20) and control group (n=20). The program consisted of 12 individual sessions using one unit from Projeto Parceria (Partnership Project), with specific guidelines and materials on positive parenting, followed by observational sessions of mother-child interaction with live coaching and a video feedback session in the lab. The study used an equivalent group experimental design with pre/post-test and follow-up, in randomized controlled trials. Measures involved: Initial Interview; Strengths and Difficulties Questionnaire (SDQ) - parent and child versions; Beck Depression Inventory (BDI); observational sessions with a protocol; and a Program Evaluation by participants. Analysis of mixed models for repeated measures revealed significant positive effects on the BDI and SDQ total scores, as well as less Conduct problems and Hyperactivity in SDQ measures from the experimental group mothers, comparing pre with post-test. Observational data also indicated significant improvement in positive interaction from the experimental group mothers at post-test, in comparison with controls. No significant results were found, however, in children's observational measures. Limitations of the study involved using a restricted sample, among others. Implications for future research are suggested. Copyright © 2017 Elsevier Ltd. All rights reserved.

Experiment Design for Nonparametric Models Based On Minimizing Bayes Risk: Application to Voriconazole1

PubMed Central

Bayard, David S.; Neely, Michael

2016-01-01

An experimental design approach is presented for individualized therapy in the special case where the prior information is specified by a nonparametric (NP) population model. Here, a nonparametric model refers to a discrete probability model characterized by a finite set of support points and their associated weights. An important question arises as to how to best design experiments for this type of model. Many experimental design methods are based on Fisher Information or other approaches originally developed for parametric models. While such approaches have been used with some success across various applications, it is interesting to note that they largely fail to address the fundamentally discrete nature of the nonparametric model. Specifically, the problem of identifying an individual from a nonparametric prior is more naturally treated as a problem of classification, i.e., to find a support point that best matches the patient’s behavior. This paper studies the discrete nature of the NP experiment design problem from a classification point of view. Several new insights are provided including the use of Bayes Risk as an information measure, and new alternative methods for experiment design. One particular method, denoted as MMopt (Multiple-Model Optimal), will be examined in detail and shown to require minimal computation while having distinct advantages compared to existing approaches. Several simulated examples, including a case study involving oral voriconazole in children, are given to demonstrate the usefulness of MMopt in pharmacokinetics applications. PMID:27909942

Experiment design for nonparametric models based on minimizing Bayes Risk: application to voriconazole¹.

PubMed

Bayard, David S; Neely, Michael

2017-04-01

An experimental design approach is presented for individualized therapy in the special case where the prior information is specified by a nonparametric (NP) population model. Here, a NP model refers to a discrete probability model characterized by a finite set of support points and their associated weights. An important question arises as to how to best design experiments for this type of model. Many experimental design methods are based on Fisher information or other approaches originally developed for parametric models. While such approaches have been used with some success across various applications, it is interesting to note that they largely fail to address the fundamentally discrete nature of the NP model. Specifically, the problem of identifying an individual from a NP prior is more naturally treated as a problem of classification, i.e., to find a support point that best matches the patient's behavior. This paper studies the discrete nature of the NP experiment design problem from a classification point of view. Several new insights are provided including the use of Bayes Risk as an information measure, and new alternative methods for experiment design. One particular method, denoted as MMopt (multiple-model optimal), will be examined in detail and shown to require minimal computation while having distinct advantages compared to existing approaches. Several simulated examples, including a case study involving oral voriconazole in children, are given to demonstrate the usefulness of MMopt in pharmacokinetics applications.

Operator assistant systems - An experimental approach using a telerobotics application

NASA Technical Reports Server (NTRS)

Boy, Guy A.; Mathe, Nathalie

1993-01-01

This article presents a knowledge-based system methodology for developing operator assistant (OA) systems in dynamic and interactive environments. This is a problem both of training and design, which is the subject of this article. Design includes both design of the system to be controlled and design of procedures for operating this system. A specific knowledge representation is proposed for representing the corresponding system and operational knowledge. This representation is based on the situation recognition and analytical reasoning paradigm. It tries to make explicit common factors involved in both human and machine intelligence, including perception and reasoning. An OA system based on this representation has been developed for space telerobotics. Simulations have been carried out with astronauts and the resulting protocols have been analyzed. Results show the relevance of the approach and have been used for improving the knowledge representation and the OA architecture.

Design of a finger base-type pulse oximeter

NASA Astrophysics Data System (ADS)

Lin, Bor-Shyh; Huang, Cheng-Yang; Chen, Chien-Yue; Lin, Jiun-Hung

2016-01-01

A pulse oximeter is a common medical instrument used for noninvasively monitoring arterial oxygen saturation (SpO2). Currently, the fingertip-type pulse oximeter is the prevalent type of pulse oximeter used. However, it is inconvenient for long-term monitoring, such as that under motion. In this study, a wearable and wireless finger base-type pulse oximeter was designed and implemented using the tissue optical simulation technique and the Monte Carlo method. The results revealed that a design involving placing the light source at 135°-165° and placing the detector at 75°-90° or 90°-105° yields the optimal conditions for measuring SpO2. Finally, the wearable and wireless finger base-type pulse oximeter was implemented and compared with the commercial fingertip-type pulse oximeter. The experimental results showed that the proposed optimal finger base-type pulse oximeter design can facilitate precise SpO2 measurement.

Design of a finger base-type pulse oximeter.

PubMed

Lin, Bor-Shyh; Huang, Cheng-Yang; Chen, Chien-Yue; Lin, Jiun-Hung

2016-01-01

A pulse oximeter is a common medical instrument used for noninvasively monitoring arterial oxygen saturation (SpO2). Currently, the fingertip-type pulse oximeter is the prevalent type of pulse oximeter used. However, it is inconvenient for long-term monitoring, such as that under motion. In this study, a wearable and wireless finger base-type pulse oximeter was designed and implemented using the tissue optical simulation technique and the Monte Carlo method. The results revealed that a design involving placing the light source at 135°-165° and placing the detector at 75°-90° or 90°-105° yields the optimal conditions for measuring SpO2. Finally, the wearable and wireless finger base-type pulse oximeter was implemented and compared with the commercial fingertip-type pulse oximeter. The experimental results showed that the proposed optimal finger base-type pulse oximeter design can facilitate precise SpO2 measurement.

Design of a Balun Bandpass Filter with Asymmetrical Coupled Microstrip Lines

NASA Astrophysics Data System (ADS)

Wang, Xuedao; Wang, Jianpeng; Zhang, Gang; Huang, Feng

2017-07-01

A new microstrip coupled-line balun topology and its application to the balun bandpass filter (BPF) with a triple mode response are proposed in this paper. The involved balun structure is composed of two back-to-back quarter-wavelength (λ/4) asymmetrical coupled-line sections. Detailed design formulas based on the asymmetrical coupled-line theory are given to validate the feasibility of the balun. Besides, to obtain filtering performance simultaneously, the balun is then effectively integrated with a pair of triple mode resonators. To demonstrate the design concept of the balun BPF, a prototype operating at 2.4 GHz with the fractional bandwidth (FBW) of about 19.2 % is designed, fabricated, and measured. Results indicate that between the two balanced outputs, the amplitude imbalance is less than 0.3 dB and the phase difference is within 180°±5° inside the whole passband. Both simulated and experimental results are in good agreement.

A novel framework for virtual prototyping of rehabilitation exoskeletons.

PubMed

Agarwal, Priyanshu; Kuo, Pei-Hsin; Neptune, Richard R; Deshpande, Ashish D

2013-06-01

Human-worn rehabilitation exoskeletons have the potential to make therapeutic exercises increasingly accessible to disabled individuals while reducing the cost and labor involved in rehabilitation therapy. In this work, we propose a novel human-model-in-the-loop framework for virtual prototyping (design, control and experimentation) of rehabilitation exoskeletons by merging computational musculoskeletal analysis with simulation-based design techniques. The framework allows to iteratively optimize design and control algorithm of an exoskeleton using simulation. We introduce biomechanical, morphological, and controller measures to quantify the performance of the device for optimization study. Furthermore, the framework allows one to carry out virtual experiments for testing specific "what-if" scenarios to quantify device performance and recovery progress. To illustrate the application of the framework, we present a case study wherein the design and analysis of an index-finger exoskeleton is carried out using the proposed framework.

Titanium-doped sapphire laser research and design study

NASA Technical Reports Server (NTRS)

Moulton, Peter F.

1987-01-01

Three main topics were considered in this study: the fundamental laser parameters of titanium-doped sapphire, characterization of commercially grown material, and design of a tunable, narrow-linewidth laser. Fundamental parameters investigated included the gain cross section, upper-state lifetime as a function of temperature and the surface-damage threshold. Commercial material was found to vary widely in the level of absorption of the laser wavelength with the highest absorption in Czochralski-grown crystals. Several Yi:sapphire lasers were constructed, including a multimode laser with greater than 50mJ of output energy and a single-transverse-mode ring laser, whose spectral and temporal characteristics were completely characterized. A design for a narrow-linewidth (single-frequency) Ti:sapphire laser was developed, based on the results of the experimental work. The design involves the use of a single-frequency, quasi-cw master oscillator, employed as an injection source for a pulsed ring laser.

Design of energy harvesting systems for harnessing vibrational motion from human and vehicular motion

NASA Astrophysics Data System (ADS)

Wickenheiser, Adam; Garcia, Ephrahim

2010-04-01

In much of the vibration-based energy harvesting literature, devices are modeled, designed, and tested for dissipating energy across a resistive load at a single base excitation frequency. This paper presents several practical scenarios germane to tracking, sensing, and wireless communication on humans and land vehicles. Measured vibrational data from these platforms are used to provide a time-varying, broadband input to the energy harvesting system. Optimal power considerations are given for several circuit topologies, including a passive rectifier circuit and active, switching methods. Under various size and mass constraints, the optimal design is presented for two scenarios: walking and idling a car. The frequency response functions are given alongside time histories of the power harvested using the experimental base accelerations recorded. The issues involved in designing an energy harvester for practical (i.e. timevarying, non-sinusoidal) applications are discussed.

Nonlinear Aerodynamics and the Design of Wing Tips

NASA Technical Reports Server (NTRS)

Kroo, Ilan

1991-01-01

The analysis and design of wing tips for fixed wing and rotary wing aircraft still remains part art, part science. Although the design of airfoil sections and basic planform geometry is well developed, the tip regions require more detailed consideration. This is important because of the strong impact of wing tip flow on wing drag; although the tip region constitutes a small portion of the wing, its effect on the drag can be significant. The induced drag of a wing is, for a given lift and speed, inversely proportional to the square of the wing span. Concepts are proposed as a means of reducing drag. Modern computational methods provide a tool for studying these issues in greater detail. The purpose of the current research program is to improve the understanding of the fundamental issues involved in the design of wing tips and to develop the range of computational and experimental tools needed for further study of these ideas.

Sound reduction of air compressors using a systematic approach

NASA Astrophysics Data System (ADS)

Moylan, Justin Tharp

The noise emitted by portable electric air compressors can often be a nuisance or potentially hazardous to the operator or others nearby. Therefore, reducing the noise of these air compressors is desired. This research focuses on compressors with a reciprocating piston design as this is the most common type of pump design for portable compressors. An experimental setup was developed to measure the sound and vibration of the air compressors, including testing inside a semi-anechoic chamber. The design of a quiet air compressor was performed in four stages: 1) Teardown and benchmarking of air compressors, 2) Identification and isolation of noise sources, 3) Development of individual means to quiet noise sources, 4) Selection and testing of integrated solutions. The systematic approach and results for each of these stages will be discussed. Two redesigned solutions were developed and measured to be approximately 65% quieter than the previous unmodified compressor. An additional analysis was performed on the solutions selected by the participants involved in the selection process. This analysis involved determining which of the design criteria each participant considered most important when selecting solutions. The results from each participant were then compared to their educational background and experience and correlations were identified. The correlations discovered suggest that educational background and experience may be key determinants for the preference models developed.

Self-Calibration and Optimal Response in Intelligent Sensors Design Based on Artificial Neural Networks

PubMed Central

Rivera, José; Carrillo, Mariano; Chacón, Mario; Herrera, Gilberto; Bojorquez, Gilberto

2007-01-01

The development of smart sensors involves the design of reconfigurable systems capable of working with different input sensors. Reconfigurable systems ideally should spend the least possible amount of time in their calibration. An autocalibration algorithm for intelligent sensors should be able to fix major problems such as offset, variation of gain and lack of linearity, as accurately as possible. This paper describes a new autocalibration methodology for nonlinear intelligent sensors based on artificial neural networks, ANN. The methodology involves analysis of several network topologies and training algorithms. The proposed method was compared against the piecewise and polynomial linearization methods. Method comparison was achieved using different number of calibration points, and several nonlinear levels of the input signal. This paper also shows that the proposed method turned out to have a better overall accuracy than the other two methods. Besides, experimentation results and analysis of the complete study, the paper describes the implementation of the ANN in a microcontroller unit, MCU. In order to illustrate the method capability to build autocalibration and reconfigurable systems, a temperature measurement system was designed and tested. The proposed method is an improvement over the classic autocalibration methodologies, because it impacts on the design process of intelligent sensors, autocalibration methodologies and their associated factors, like time and cost.

The Design of an Experimental Apparatus to Measure the Motions of a Towed Submersible Environmental Sensor Vehicle.

DTIC Science & Technology

1983-06-01

obtained by the vertical excitation apparatus, keeping the horizontal excitation apparatus .4 at zero frequ ncy. The model c.g. moves in a sinusoidal...point between the support plates and the rail module, foam rubber pads were inserted.. These pads increased the coefficient of friction and reduced the...involved the CADIG 4051 Tektronix computer data SI acquistion and graphic display system. The Tektronix 4050 series computers can be used as stand alone

A review and preliminary evaluation of methodological factors in performance assessments of time-varying aircraft noise effects

NASA Technical Reports Server (NTRS)

Coates, G. D.; Alluisi, E. A.

1975-01-01

The effects of aircraft noise on human performance is considered. Progress is reported in the following areas: (1) review of the literature to identify the methodological and stimulus parameters involved in the study of noise effects on human performance; (2) development of a theoretical framework to provide working hypotheses as to the effects of noise on complex human performance; and (3) data collection on the first of several experimental investigations designed to provide tests of the hypotheses.

High-temperature gas-cooled reactor technology development program. Annual progress report for period ending December 31, 1982

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

Kasten, P.R.; Rittenhouse, P.L.; Bartine, D.E.

1983-06-01

During 1982 the High-Temperature Gas-Cooled Reactor (HTGR) Technology Program at Oak Ridge National Laboratory (ORNL) continued to develop experimental data required for the design and licensing of cogeneration HTGRs. The program involves fuels and materials development (including metals, graphite, ceramic, and concrete materials), HTGR chemistry studies, structural component development and testing, reactor physics and shielding studies, performance testing of the reactor core support structure, and HTGR application and evaluation studies.

Some effects of wing and body geometry on the aerodynamic characteristics of configurations designed for high supersonic Mach numbers

NASA Technical Reports Server (NTRS)

Spearman, M. L.; Tice, David C.; Braswell, Dorothy O.

1992-01-01

Experimental and theoretical results are presented for a family of aerodynamic configurations for flight Mach numbers as high as Mach 8. All of these generic configurations involved 70-deg sweep delta planform wings of three different areas and three fuselage shapes with circular-to-elliptical cross sections. It is noted that fuselage ellipticity enhances lift-curve slope and maximum L/D, while decreasing static longitudinal stability (especially with smaller wing areas).

Dynamic Loading and Characterization of Fiber-Reinforced Composites

NASA Astrophysics Data System (ADS)

Sierakowski, Robert L.; Chaturvedi, Shive K.

1997-02-01

Emphasizing polymer based fiber-reinforced composites, this book is designed to provide readers with a significant understanding of the complexities involved in characterizing dynamic events and the corresponding response of advanced fiber composite materials and structures. These elements include dynamic loading devices, material properties characterization, analytical and experimental techniques to assess the damage and failure modes associated with various dynamic loading events. Concluding remarks are presented throughout the text which summarize key points and raise issues related to important research needed.

Design of Electrical Stimulation Bioreactors for Cardiac Tissue Engineering

PubMed Central

Tandon, N.; Marsano, A.; Cannizzaro, C.; Voldman, J.; Vunjak-Novakovic, G.

2009-01-01

Electrical stimulation has been shown to improve functional assembly of cardiomyocytes in vitro for cardiac tissue engineering. Carbon electrodes were found in past studies to have the best current injection characteristics. The goal of this study was to develop rational experimental design principles for the electrodes and stimulation regime, in particular electrode configuration, electrode ageing, and stimulation amplitude. Carbon rod electrodes were compared via electrochemical impedance spectroscopy (EIS) and we identified a safety range of 0 to 8 V/cm by comparing excitation thresholds and maximum capture rates for neonatal rat cardiomyocytes cultured with electrical stimulation. We conclude with recommendations for studies involving carbon electrodes for cardiac tissue engineering. PMID:19163486

Paper simulation techniques in user requirements analysis for interactive computer systems

NASA Technical Reports Server (NTRS)

Ramsey, H. R.; Atwood, M. E.; Willoughby, J. K.

1979-01-01

This paper describes the use of a technique called 'paper simulation' in the analysis of user requirements for interactive computer systems. In a paper simulation, the user solves problems with the aid of a 'computer', as in normal man-in-the-loop simulation. In this procedure, though, the computer does not exist, but is simulated by the experimenters. This allows simulated problem solving early in the design effort, and allows the properties and degree of structure of the system and its dialogue to be varied. The technique, and a method of analyzing the results, are illustrated with examples from a recent paper simulation exercise involving a Space Shuttle flight design task

Participatory adaptive management leads to environmental learning outcomes extending beyond the sphere of science.

PubMed

Fujitani, Marie; McFall, Andrew; Randler, Christoph; Arlinghaus, Robert

2017-06-01

Resolving uncertainties in managed social-ecological systems requires adaptive experimentation at whole-ecosystem levels. However, whether participatory adaptive management fosters ecological understanding among stakeholders beyond the sphere of science is unknown. We experimentally involved members of German angling clubs ( n = 181 in workshops, n = 2483 in total) engaged in self-governance of freshwater fisheries resources in a large-scale ecological experiment of active adaptive management of fish stocking, which constitutes a controversial management practice for biodiversity and ecosystem functioning when conducted inappropriately. The collaborative ecological experiments spanned several years and manipulated fish densities in 24 lakes with two species. In parallel, we experimentally compared changes in ecological knowledge and antecedents of proenvironmental behavior in stakeholders and managers who were members of a participatory adaptive management treatment group, with those receiving only a standard lecture, relative to placebo controls. Using a within-subjects pretest-posttest control design, changes in ecological knowledge, environmental beliefs, attitudes, norms, and behavioral intentions were evaluated. Participants in adaptive management retained more knowledge of ecological topics after a period of 8 months compared to those receiving a standard lecture, both relative to controls. Involvement in adaptive management was also the only treatment that altered personal norms and beliefs related to stocking. Critically, only the stakeholders who participated in adaptive management reduced their behavioral intentions to engage in fish stocking in the future. Adaptive management is essential for robust ecological knowledge, and we show that involving stakeholders in adaptive management experiments is a powerful tool to enhance ecological literacy and build environmental capacity to move toward sustainability.

Participatory adaptive management leads to environmental learning outcomes extending beyond the sphere of science

PubMed Central

Fujitani, Marie; McFall, Andrew; Randler, Christoph; Arlinghaus, Robert

2017-01-01

Resolving uncertainties in managed social-ecological systems requires adaptive experimentation at whole-ecosystem levels. However, whether participatory adaptive management fosters ecological understanding among stakeholders beyond the sphere of science is unknown. We experimentally involved members of German angling clubs (n = 181 in workshops, n = 2483 in total) engaged in self-governance of freshwater fisheries resources in a large-scale ecological experiment of active adaptive management of fish stocking, which constitutes a controversial management practice for biodiversity and ecosystem functioning when conducted inappropriately. The collaborative ecological experiments spanned several years and manipulated fish densities in 24 lakes with two species. In parallel, we experimentally compared changes in ecological knowledge and antecedents of proenvironmental behavior in stakeholders and managers who were members of a participatory adaptive management treatment group, with those receiving only a standard lecture, relative to placebo controls. Using a within-subjects pretest-posttest control design, changes in ecological knowledge, environmental beliefs, attitudes, norms, and behavioral intentions were evaluated. Participants in adaptive management retained more knowledge of ecological topics after a period of 8 months compared to those receiving a standard lecture, both relative to controls. Involvement in adaptive management was also the only treatment that altered personal norms and beliefs related to stocking. Critically, only the stakeholders who participated in adaptive management reduced their behavioral intentions to engage in fish stocking in the future. Adaptive management is essential for robust ecological knowledge, and we show that involving stakeholders in adaptive management experiments is a powerful tool to enhance ecological literacy and build environmental capacity to move toward sustainability. PMID:28630904

Age and interviewer behavior as predictors of interrogative suggestibility.

PubMed

Dukala, Karolina; Polczyk, Romuald

2014-05-01

The main objective was to explore the influence of interviewer behavior-abrupt versus friendly-and the age of participants on interrogative suggestibility. The study involved 42 young adults and 50 elderly participants. The Gudjonsson Suggestibility Scale 2 was used. Data analysis involved a 2-factor between-subjects design (interviewer behavior × age) and mediation analysis. The scores of elderly participants were significantly lower than younger adults on memory indices and significantly higher on some suggestibility indexes. Some suggestibility indices in the abrupt experimental condition were higher than those in the friendly experimental condition. Elderly participants who were interviewed under the abrupt condition were more likely to change their answers after receiving negative feedback than younger adults. Memory quality was a mediator of the relationship between age and the tendency to yield to suggestive questions. Self-appraisal of memory was a mediator between both age and interviewer behavior and the tendency to change answers after negative feedback. Mechanisms of the relationship between age, interviewer behavior, and suggestibility are discussed on the basis of the mediational analyses. The findings suggest that a friendly manner should be adopted when interrogating witnesses.

Aircraft as Research Tools

NASA Technical Reports Server (NTRS)

1999-01-01

Aeronautical research usually begins with computers, wind tunnels, and flight simulators, but eventually the theories must fly. This is when flight research begins, and aircraft are the primary tools of the trade. Flight research involves doing precision maneuvers in either a specially built experimental aircraft or an existing production airplane that has been modified. For example, the AD-1 was a unique airplane made only for flight research, while the NASA F-18 High Alpha Research Vehicle (HARV) was a standard fighter aircraft that was transformed into a one-of-a-kind aircraft as it was fitted with new propulsion systems, flight controls, and scientific equipment. All research aircraft are able to perform scientific experiments because of the onboard instruments that record data about its systems, aerodynamics, and the outside environment. Since the 1970's, NASA flight research has become more comprehensive, with flights involving everything form Space Shuttles to ultralights. NASA now flies not only the fastest airplanes, but some of the slowest. Flying machines continue to evolve with new wing designs, propulsion systems, and flight controls. As always, a look at today's experimental research aircraft is a preview of the future.

Evaluation of study design variables and their impact on food-maintained operant responding in mice.

PubMed

Haluk, Desirae M; Wickman, Kevin

2010-03-05

Operant conditioning paradigms are useful for studying factors involved in reward, particularly when combined with the tools of genetic manipulation in mice. Published operant studies involving mice vary widely with respect to design, and insight into the consequences of design choices on performance in mice is limited. Here, we evaluated the impact of five design variables on the performance of inbred male mice in operant tasks involving solid food pellets as reinforcing agents. We found that the use of lever-press or nose-poke during FR1 sessions did not impact the performance of C57BL/6 mice, but that the lever-press approach correlated with enhanced performance during PR testing. While FR1 session duration had a notable impact on the rate of acquisition of food-maintained responding, performance during FR1 and PR sessions was largely unaffected. Higher order schedules of reinforcement (FR3 and FR5) led to elevated responding during both FR and PR sessions, and improved the correspondence between rewards earned and consumed. Single and group-housed mice performed indistinguishably during FR1 and PR sessions, while environmental enrichment combined with group housing accelerated the rate of acquisition of food-maintained responding while decreasing responding during PR testing. Finally, while C57BL/6 and 129/Sv mice exhibited comparable behavior during FR1 sessions, C57BL/6 mice tended to acquire food-maintained responding faster than 129/Sv counterparts, and exhibited elevated responding during PR testing. Altogether, our findings indicate that while operant performance for food in mice is relatively insensitive to many study parameters, experimental outcomes can be shaped predictably with proper design decisions. Copyright 2009 Elsevier B.V. All rights reserved.

Quasi-Experimental Designs for Causal Inference

ERIC Educational Resources Information Center

Kim, Yongnam; Steiner, Peter

2016-01-01

When randomized experiments are infeasible, quasi-experimental designs can be exploited to evaluate causal treatment effects. The strongest quasi-experimental designs for causal inference are regression discontinuity designs, instrumental variable designs, matching and propensity score designs, and comparative interrupted time series designs. This…

First-principles chemical kinetic modeling of methyl trans-3-hexenoate epoxidation by HO 2

DOE PAGES

Cagnina, S.; Nicolle, Andre; de Bruin, T.; ...

2017-02-16

The design of innovative combustion processes relies on a comprehensive understanding of biodiesel oxidation kinetics. The present study aims at unraveling the reaction mechanism involved in the epoxidation of a realistic biodiesel surrogate, methyl trans-3-hexenoate, by hydroperoxy radicals using a bottom-up theoretical kinetics methodology. The obtained rate constants are in good agreement with experimental data for alkene epoxidation by HO 2. The impact of temperature and pressure on epoxidation pathways involving H-bonded and non-H-bonded conformers was assessed. As a result, the obtained rate constant was finally implemented into a state-of-the-art detailed combustion mechanism, resulting in fairly good agreement with enginemore » experiments.« less

Microwave Tunable Metamaterial Based on Semiconductor-to-Metal Phase Transition.

PubMed

Zhang, Guanqiao; Ma, He; Lan, Chuwen; Gao, Rui; Zhou, Ji

2017-07-18

A microwave tunable metamaterial utilizing the semiconductor-to-metal transition of vanadium dioxide (VO 2 ) is proposed, experimentally demonstrated and theoretically scrutinized. Basic concept of the design involves the combination of temperature-dependent hysteresis in VO 2 with resonance induced heating, resulting in a nonlinear response to power input. A lithographically prepared gold split-rings resonator (SRR) array deposited with VO 2 thin film is fabricated. Transmission spectra analysis shows a clear manifestation of nonlinearity, involving power-dependence of resonant frequency as well as transmitted intensity at both elevated and room temperature. Simulation performed with CST Microwave Studio conforms with the findings. The concept may find applications in transmission modulation and frequency tuning devices working under microwave frequency bands.

Design and fabrication of forward-swept counterrotation blade configuration for wind tunnel testing

NASA Technical Reports Server (NTRS)

Nichols, G. H.

1994-01-01

Work performed by GE Aircraft on advanced counterrotation blade configuration concepts for high speed turboprop system is described. Primary emphasis was placed on theoretically and experimentally evaluating the aerodynamic, aeromechanical, and acoustic performance of GE-defined counterrotating blade concepts. Several blade design concepts were considered. Feasibility studies were conducted to evaluate a forward-swept versus an aft-swept blade application and how the given blade design would affect interaction between rotors. Two blade designs were initially selected. Both designs involved in-depth aerodynamic, aeromechanical, mechanical, and acoustic analyses followed by the fabrication of forward-swept, forward rotor blade sets to be wind tunnel tested with an aft-swept, aft rotor blade set. A third blade set was later produced from a NASA design that was based on wind tunnel test results from the first two blade sets. This blade set had a stiffer outer ply material added to the original blade design, in order to reach the design point operating line. Detailed analyses, feasibility studies, and fabrication procedures for all blade sets are presented.

The Capillary Flow Experiments Aboard the International Space Station: Increments 9-15

NASA Technical Reports Server (NTRS)

Jenson, Ryan M.; Weislogel, Mark M.; Tavan, Noel T.; Chen, Yongkang; Semerjian, Ben; Bunnell, Charles T.; Collicott, Steven H.; Klatte, Jorg; dreyer, Michael E.

2009-01-01

This report provides a summary of the experimental, analytical, and numerical results of the Capillary Flow Experiment (CFE) performed aboard the International Space Station (ISS). The experiments were conducted in space beginning with Increment 9 through Increment 16, beginning August 2004 and ending December 2007. Both primary and extra science experiments were conducted during 19 operations performed by 7 astronauts including: M. Fincke, W. McArthur, J. Williams, S. Williams, M. Lopez-Alegria, C. Anderson, and P. Whitson. CFE consists of 6 approximately 1 to 2 kg handheld experiment units designed to investigate a selection of capillary phenomena of fundamental and applied importance, such as large length scale contact line dynamics (CFE-Contact Line), critical wetting in discontinuous structures (CFE-Vane Gap), and capillary flows and passive phase separations in complex containers (CFE-Interior Corner Flow). Highly quantitative video from the simply performed flight experiments provide data helpful in benchmarking numerical methods, confirming theoretical models, and guiding new model development. In an extensive executive summary, a brief history of the experiment is reviewed before introducing the science investigated. A selection of experimental results and comparisons with both analytic and numerical predictions is given. The subsequent chapters provide additional details of the experimental and analytical methods developed and employed. These include current presentations of the state of the data reduction which we anticipate will continue throughout the year and culminate in several more publications. An extensive appendix is used to provide support material such as an experiment history, dissemination items to date (CFE publication, etc.), detailed design drawings, and crew procedures. Despite the simple nature of the experiments and procedures, many of the experimental results may be practically employed to enhance the design of spacecraft engineering systems involving capillary interface dynamics.

Thermochemical Modeling of Nonequilibrium Oxygen Flows

NASA Astrophysics Data System (ADS)

Neitzel, Kevin Joseph

The development of hypersonic vehicles leans heavily on computational simulation due to the high enthalpy flow conditions that are expensive and technically challenging to replicate experimentally. The accuracy of the nonequilibrium modeling in the computer simulations dictates the design margin that is required for the thermal protection system and flight dynamics. Previous hypersonic vehicles, such as Apollo and the Space Shuttle, were primarily concerned with re-entry TPS design. The strong flow conditions of re-entry, involving Mach numbers of 25, quickly dissociate the oxygen molecules in air. Sustained flight, hypersonic vehicles will be designed to operate in Mach number ranges of 5 to 10. The oxygen molecules will not quickly dissociate and will play an important role in the flow field behavior. The development of nonequilibrium models of oxygen is crucial for limiting modeling uncertainty. Thermochemical nonequilibrium modeling is investigated for oxygen flows. Specifically, the vibrational relaxation and dissociation behavior that dominate the nonequilibrium physics in this flight regime are studied in detail. The widely used two-temperature (2T) approach is compared to the higher fidelity and more computationally expensive state-to-state (STS) approach. This dissertation utilizes a wide range of rate sources, including newly available STS rates, to conduct a comprehensive study of modeling approaches for hypersonic nonequilibrium thermochemical modeling. Additionally, the physical accuracy of the computational methods are assessed by comparing the numerical results with available experimental data. The numerical results and experimental measurements present strong nonequilibrium, and even non-Boltzmann behavior in the vibrational energy mode for the sustained hypersonic flight regime. The STS approach is able to better capture the behavior observed in the experimental data, especially for stronger nonequilibrium conditions. Additionally, a reduced order model (ROM) modification to the 2T model is developed to improve the capability of the 2T approach framework.

The usefulness of design of experimentation in defining the effect difficult airway factors and training have on simulator oral-tracheal intubation success rates in novice intubators.

PubMed

Thomas, Frank; Carpenter, Judi; Rhoades, Carol; Holleran, Renee; Snow, Gregory

2010-04-01

This exploratory study examined novice intubators and the effect difficult airway factors have on pre- and posttraining oral-tracheal simulation intubation success rates. Using a two-level, full-factorial design of experimentation (DOE) involving a combination of six airway factors (curved vs. straight laryngoscope blade, trismus, tongue edema, laryngeal spasm, pharyngeal obstruction, or cervical immobilization), 64 airway scenarios were prospectively randomized to 12 critical care nurses to evaluate pre- and posttraining first-pass intubation success rates on a simulator. Scenario variables and intubation outcomes were analyzed using a generalized linear mixed-effects model to determine two-way main and interactive effects. Interactive effects between the six study factors were nonsignificant (p = 0.69). For both pre- and posttraining, main effects showed the straight blade (p = 0.006), tongue edema (p = 0.0001), and laryngeal spasm (p = 0.004) significantly reduced success rates, while trismus (p = 0.358), pharyngeal obstruction (p = 0.078), and cervical immobilization did not significantly change the success rate. First-pass intubation success rate on the simulator significantly improved (p = 0.005) from pre- (19%) to posttraining (36%). Design of experimentation is useful in analyzing the effect difficult airway factors and training have on simulator intubation success rates. Future quality improvement DOE simulator research studies should be performed to help clarify the relationship between simulator factors and patient intubation rates.

A More Rigorous Quasi-Experimental Alternative to the One-Group Pretest-Posttest Design.

ERIC Educational Resources Information Center

Johnson, Craig W.

1986-01-01

A simple quasi-experimental design is described which may have utility in a variety of applied and laboratory research settings where ordinarily the one-group pretest-posttest pre-experimental design might otherwise be the procedure of choice. The design approaches the internal validity of true experimental designs while optimizing external…

Using decision mapping to inform the development of a stated choice survey to elicit youth preferences for sexual and reproductive health and HIV services in rural Malawi.

PubMed

Michaels-Igbokwe, Christine; Lagarde, Mylene; Cairns, John; Terris-Prestholt, Fern

2014-03-01

The process of designing and developing discrete choice experiments (DCEs) is often under reported. The need to adequately report the results of qualitative work used to identify attributes and levels used in a DCE is recognised. However, one area that has received relatively little attention is the exploration of the choice question of interest. This paper provides a case study of the process used to design a stated preference survey to assess youth preferences for integrated sexual and reproductive health (SRH) and HIV outreach services in Malawi. Development and design consisted of six distinct but overlapping and iterative stages. Stage one was a review of the literature. Stage two involved developing a decision map to conceptualise the choice processes involved. Stage three included twelve focus group discussions with young people aged 15-24 (n = 113) and three key informant interviews (n = 3) conducted in Ntcheu District, Malawi. Stage four involved analysis of qualitative data and identification of potential attributes and levels. The choice format and experimental design were selected in stages five and six. The results of the literature review were used to develop a decision map outlining the choices that young people accessing SRH services may face. For youth that would like to use services two key choices were identified: the choice between providers and the choice of service delivery attributes within a provider type. Youth preferences for provider type are best explored using a DCE with a labelled design, while preferences for service delivery attributes associated with a particular provider are better understood using an unlabelled design. Consequently, two DCEs were adopted to jointly assess preferences in this context. Used in combination, the results of the literature review, the decision mapping process and the qualitative work provided robust approach to designing the DCEs individually and as complementary pieces of work. Copyright © 2014 Elsevier Ltd. All rights reserved.

Effects of a blended learning module on self-reported learning performances in baccalaureate nursing students.

PubMed

Hsu, Li-Ling; Hsieh, Suh-Ing

2011-11-01

This article is a report of a quasi-experimental study of the effects of blended modules on nursing students' learning of ethics course content. There is yet to be an empirically supported mix of strategies on which a working blended learning model can be built for nursing education. This was a two-group pretest and post-test quasi-experimental study in 2008 involving a total of 233 students. Two of the five clusters were designated the experimental group to experience a blended learning model, and the rest were designated the control group to be given classroom lectures only. The Case Analysis Attitude Scale, Case Analysis Self-Evaluation Scale, Blended Learning Satisfaction Scale, and Metacognition Scale were used in pretests and post-tests for the students to rate their own performance. In this study, the experimental group did not register significantly higher mean scores on the Case Analysis Attitude Scale at post-test and higher mean ranks on the Case Analysis Self-Evaluation Scale, the Blended Learning Satisfaction Scale, and the Metacognition Scale at post-test than the control group. Moreover, the experimental group registered significant progress in the mean ranks on the Case Analysis Self-Evaluation Scale and the Metacognition Scale from pretest to post-test. No between-subjects effects of four scales at post-test were found. Newly developed course modules, be it blended learning or a combination of traditional and innovative components, should be tested repeatedly for effectiveness and popularity for the purpose of facilitating the ultimate creation of a most effective course module for nursing education. © 2011 Blackwell Publishing Ltd.

Effectiveness of metal surface treatments in controlling microleakage of the acrylic resin-metal framework interface.

PubMed

Sharp, B; Morton, D; Clark, A E

2000-12-01

Microleakage at the junction between the metal alloy and acrylic resin in a removable partial denture may result in discoloration, fluid percolation, and acrylic resin deterioration. The junction between a metal alloy and acrylic resin is an area of clinical concern. Failure of a removable partial denture may be linked to this interface. Enhancing resistance to microleakage at this interface may improve the long-term union between the 2 materials. This investigation was designed to determine the effects of various metal surface treatment protocols on microleakage and bond strength between the metal alloy and acrylic resin used in the fabrication of a removable partial denture. Ninety-six nickel-chromium-beryllium alloy specimens were randomly divided into 8 groups. After adaptation of baseplate wax, each specimen was invested. Subsequent to wax removal, each specimen was divided into a control half and an experimental half. Air abrasion, tinplating/oxidation, and silanation were evaluated individually and in all combinations. Heat-polymerized acrylic resin was processed against all specimens before storage in distilled water at 37 degrees C for 72 hours. Each specimen then was thermocycled in distilled water (3000 cycles) before immersion in sodium fluorescein dye for 24 hours. Counting grids that exhibited dye penetration under ultraviolet light exposure allowed assessment of microleakage. Air abrasion resulted in a significant decrease in microleakage when used individually and in all combinations (P<0.05). All experimental combinations that did not involve air abrasion demonstrated no significant reduction in measured microleakage between the experimental and control sides. Tukey's pair-wise comparison of the difference in the mean number of squares exhibiting microleakage between the control and treated sites for each experimental group revealed a significant difference, based on the involvement of air abrasion. Groups involving air abrasion did not differ significantly from each other (P<0.05). In addition, no significant difference was detected between groups not involving air abrasion (P<0.05). Air abrasion, alone and in combination with tinplating/oxidation and with silanation, resulted in a significant reduction in microleakage between the metal alloy and acrylic resin.

Rocket Engine Turbine Blade Surface Pressure Distributions Experiment and Computations

NASA Technical Reports Server (NTRS)

Hudson, Susan T.; Zoladz, Thomas F.; Dorney, Daniel J.; Turner, James (Technical Monitor)

2002-01-01

Understanding the unsteady aspects of turbine rotor flow fields is critical to successful future turbine designs. A technology program was conducted at NASA's Marshall Space Flight Center to increase the understanding of unsteady environments for rocket engine turbines. The experimental program involved instrumenting turbine rotor blades with miniature surface mounted high frequency response pressure transducers. The turbine model was then tested to measure the unsteady pressures on the rotor blades. The data obtained from the experimental program is unique in two respects. First, much more unsteady data was obtained (several minutes per set point) than has been possible in the past. Also, an extensive steady performance database existed for the turbine model. This allowed an evaluation of the effect of the on-blade instrumentation on the turbine's performance. A three-dimensional unsteady Navier-Stokes analysis was also used to blindly predict the unsteady flow field in the turbine at the design operating conditions and at +15 degrees relative incidence to the first-stage rotor. The predicted time-averaged and unsteady pressure distributions show good agreement with the experimental data. This unique data set, the lessons learned for acquiring this type of data, and the improvements made to the data analysis and prediction tools are contributing significantly to current Space Launch Initiative turbine airflow test and blade surface pressure prediction efforts.

Fractional Factorial Design Study on the Performance of GAC-Enhanced Electrocoagulation Process Involved in Color Removal from Dye Solutions.

PubMed

Secula, Marius Sebastian; Cretescu, Igor; Cagnon, Benoit; Manea, Liliana Rozemarie; Stan, Corneliu Sergiu; Breaban, Iuliana Gabriela

2013-07-10

The aim of this study was to determine the effects of main factors and interactions on the color removal performance from dye solutions using the electrocoagulation process enhanced by adsorption on Granular Activated Carbon (GAC). In this study, a mathematical approach was conducted using a two-level fractional factorial design ( FFD ) for a given dye solution. Three textile dyes: Acid Blue 74, Basic Red 1, and Reactive Black 5 were used. Experimental factors used and their respective levels were: current density (2.73 or 27.32 A/m²), initial pH of aqueous dye solution (3 or 9), electrocoagulation time (20 or 180 min), GAC dose (0.1 or 0.5 g/L), support electrolyte (2 or 50 mM), initial dye concentration (0.05 or 0.25 g/L) and current type (Direct Current- DC or Alternative Pulsed Current- APC ). GAC-enhanced electrocoagulation performance was analyzed statistically in terms of removal efficiency, electrical energy, and electrode material consumptions, using modeling polynomial equations. The statistical significance of GAC dose level on the performance of GAC enhanced electrocoagulation and the experimental conditions that favor the process operation of electrocoagulation in APC regime were determined. The local optimal experimental conditions were established using a multi-objective desirability function method.

Adaptive restoration of river terrace vegetation through iterative experiments

USGS Publications Warehouse

Dela Cruz, Michelle P.; Beauchamp, Vanessa B.; Shafroth, Patrick B.; Decker, Cheryl E.; O’Neil, Aviva

2014-01-01

Restoration projects can involve a high degree of uncertainty and risk, which can ultimately result in failure. An adaptive restoration approach can reduce uncertainty through controlled, replicated experiments designed to test specific hypotheses and alternative management approaches. Key components of adaptive restoration include willingness of project managers to accept the risk inherent in experimentation, interest of researchers, availability of funding for experimentation and monitoring, and ability to restore sites as iterative experiments where results from early efforts can inform the design of later phases. This paper highlights an ongoing adaptive restoration project at Zion National Park (ZNP), aimed at reducing the cover of exotic annual Bromus on riparian terraces, and revegetating these areas with native plant species. Rather than using a trial-and-error approach, ZNP staff partnered with academic, government, and private-sector collaborators to conduct small-scale experiments to explicitly address uncertainties concerning biomass removal of annual bromes, herbicide application rates and timing, and effective seeding methods for native species. Adaptive restoration has succeeded at ZNP because managers accept the risk inherent in experimentation and ZNP personnel are committed to continue these projects over a several-year period. Techniques that result in exotic annual Bromus removal and restoration of native plant species at ZNP can be used as a starting point for adaptive restoration projects elsewhere in the region.

Fractional Factorial Design Study on the Performance of GAC-Enhanced Electrocoagulation Process Involved in Color Removal from Dye Solutions

PubMed Central

Secula, Marius Sebastian; Cretescu, Igor; Cagnon, Benoit; Manea, Liliana Rozemarie; Stan, Corneliu Sergiu; Breaban, Iuliana Gabriela

2013-01-01

The aim of this study was to determine the effects of main factors and interactions on the color removal performance from dye solutions using the electrocoagulation process enhanced by adsorption on Granular Activated Carbon (GAC). In this study, a mathematical approach was conducted using a two-level fractional factorial design (FFD) for a given dye solution. Three textile dyes: Acid Blue 74, Basic Red 1, and Reactive Black 5 were used. Experimental factors used and their respective levels were: current density (2.73 or 27.32 A/m2), initial pH of aqueous dye solution (3 or 9), electrocoagulation time (20 or 180 min), GAC dose (0.1 or 0.5 g/L), support electrolyte (2 or 50 mM), initial dye concentration (0.05 or 0.25 g/L) and current type (Direct Current—DC or Alternative Pulsed Current—APC). GAC-enhanced electrocoagulation performance was analyzed statistically in terms of removal efficiency, electrical energy, and electrode material consumptions, using modeling polynomial equations. The statistical significance of GAC dose level on the performance of GAC enhanced electrocoagulation and the experimental conditions that favor the process operation of electrocoagulation in APC regime were determined. The local optimal experimental conditions were established using a multi-objective desirability function method. PMID:28811405

Statistical Metamodeling and Sequential Design of Computer Experiments to Model Glyco-Altered Gating of Sodium Channels in Cardiac Myocytes.

PubMed

Du, Dongping; Yang, Hui; Ednie, Andrew R; Bennett, Eric S

2016-09-01

Glycan structures account for up to 35% of the mass of cardiac sodium ( Nav ) channels. To question whether and how reduced sialylation affects Nav activity and cardiac electrical signaling, we conducted a series of in vitro experiments on ventricular apex myocytes under two different glycosylation conditions, reduced protein sialylation (ST3Gal4(-/-)) and full glycosylation (control). Although aberrant electrical signaling is observed in reduced sialylation, realizing a better understanding of mechanistic details of pathological variations in INa and AP is difficult without performing in silico studies. However, computer model of Nav channels and cardiac myocytes involves greater levels of complexity, e.g., high-dimensional parameter space, nonlinear and nonconvex equations. Traditional linear and nonlinear optimization methods have encountered many difficulties for model calibration. This paper presents a new statistical metamodeling approach for efficient computer experiments and optimization of Nav models. First, we utilize a fractional factorial design to identify control variables from the large set of model parameters, thereby reducing the dimensionality of parametric space. Further, we develop the Gaussian process model as a surrogate of expensive and time-consuming computer models and then identify the next best design point that yields the maximal probability of improvement. This process iterates until convergence, and the performance is evaluated and validated with real-world experimental data. Experimental results show the proposed algorithm achieves superior performance in modeling the kinetics of Nav channels under a variety of glycosylation conditions. As a result, in silico models provide a better understanding of glyco-altered mechanistic details in state transitions and distributions of Nav channels. Notably, ST3Gal4(-/-) myocytes are shown to have higher probabilities accumulated in intermediate inactivation during the repolarization and yield a shorter refractory period than WTs. The proposed statistical design of computer experiments is generally extensible to many other disciplines that involve large-scale and computationally expensive models.

Are decisions under risk malleable?

PubMed

Fong, C; McCabe, K

1999-09-14

Human decision making under risk and uncertainty may depend on individual involvement in the outcome-generating process. Expected utility theory is silent on this issue. Prospect theory in its current form offers little, if any, prediction of how or why involvement in a process should matter, although it may offer ex post interpretations of empirical findings. Well-known findings in psychology demonstrate that when subjects exercise more involvement or choice in lottery procedures, they value their lottery tickets more highly. This often is interpreted as an "illusion of control," meaning that when subjects are more involved in a lottery, they may believe they are more likely to win, perhaps because they perceive that they have more control over the outcome. Our experimental design eliminates several possible alternative explanations for the results of previous studies in an experiment that varies the degree and type of involvement in lottery procedures. We find that in treatments with more involvement subjects on average place less rather than more value on their lottery tickets. One possible explanation for this is that involvement interacts with loss aversion by causing subjects to weigh losses more heavily than they would otherwise. One implication of our study is that involvement, either independently or in interaction with myopic loss aversion, may help explain the extreme risk aversion of bond investors.

Rotating rake design for unique measurement of fan-generated spinning acoustic modes

NASA Technical Reports Server (NTRS)

Konno, Kevin E.; Hausmann, Clifford R.

1993-01-01

In light of the current emphasis on noise reduction in subsonic aircraft design, NASA has been actively studying the source of and propagation of noise generated by subsonic fan engines. NASA/LeRC has developed and tested a unique method of accurately measuring these spinning acoustic modes generated by an experimental fan. This mode measuring method is based on the use of a rotating microphone rake. Testing was conducted in the 9 x 15 Low-speed Wind Tunnel. The rotating rake was tested with the Advanced Ducted Propeller (ADP) model. This memorandum discusses the design and performance of the motor/drive system for the fan-synchronized rotating acoustic rake. This novel motor/drive design approach is now being adapted for additional acoustic mode studies in new test rigs as baseline data for the future design of active noise control for subsonic fan engines. Included in this memorandum are the research requirements, motor/drive specifications, test performance results, and a description of the controls and software involved.

A Novel Latin Hypercube Algorithm via Translational Propagation

PubMed Central

Pan, Guang; Ye, Pengcheng

2014-01-01

Metamodels have been widely used in engineering design to facilitate analysis and optimization of complex systems that involve computationally expensive simulation programs. The accuracy of metamodels is directly related to the experimental designs used. Optimal Latin hypercube designs are frequently used and have been shown to have good space-filling and projective properties. However, the high cost in constructing them limits their use. In this paper, a methodology for creating novel Latin hypercube designs via translational propagation and successive local enumeration algorithm (TPSLE) is developed without using formal optimization. TPSLE algorithm is based on the inspiration that a near optimal Latin Hypercube design can be constructed by a simple initial block with a few points generated by algorithm SLE as a building block. In fact, TPSLE algorithm offers a balanced trade-off between the efficiency and sampling performance. The proposed algorithm is compared to two existing algorithms and is found to be much more efficient in terms of the computation time and has acceptable space-filling and projective properties. PMID:25276844

The effects of small-scale, homelike facilities for older people with dementia on residents, family caregivers and staff: design of a longitudinal, quasi-experimental study.

PubMed

Verbeek, Hilde; van Rossum, Erik; Zwakhalen, Sandra M G; Ambergen, Ton; Kempen, Gertrudis I J M; Hamers, Jan P H

2009-01-20

Small-scale and homelike facilities for older people with dementia are rising in current dementia care. In these facilities, a small number of residents live together and form a household with staff. Normal, daily life and social participation are emphasized. It is expected that these facilities improve residents' quality of life. Moreover, it may have a positive influence on staff's job satisfaction and families involvement and satisfaction with care. However, effects of these small-scale and homelike facilities have hardly been investigated. Since the number of people with dementia increases, and institutional long-term care is more and more organized in small-scale and homelike facilities, more research into effects is necessary. This paper presents the design of a study investigating effects of small-scale living facilities in the Netherlands on residents, family caregivers and nursing staff. A longitudinal, quasi-experimental study is carried out, in which 2 dementia care settings are compared: small-scale living facilities and regular psychogeriatric wards in traditional nursing homes. Data is collected from residents, their family caregivers and nursing staff at baseline and after 6 and 12 months of follow-up. Approximately 2 weeks prior to baseline measurement, residents are screened on cognition and activities of daily living (ADL). Based on this screening profile, residents in psychogeriatric wards are matched to residents living in small-scale living facilities. The primary outcome measure for residents is quality of life. In addition, neuropsychiatric symptoms, depressive symptoms and social engagement are assessed. Involvement with care, perceived burden and satisfaction with care provision are primary outcome variables for family caregivers. The primary outcomes for nursing staff are job satisfaction and motivation. Furthermore, job characteristics social support, autonomy and workload are measured. A process evaluation is performed to investigate to what extent small-scale living facilities and psychogeriatric wards are designed as they were intended. In addition, participants' satisfaction and experiences with small-scale living facilities are investigated. A longitudinal, quasi-experimental study is presented to investigate effects of small-scale living facilities. Although some challenges concerning this design exist, it is currently the most feasible method to assess effects of this relatively new dementia care setting.

Landsat D Thematic Mapper image dimensionality reduction and geometric correction accuracy

NASA Technical Reports Server (NTRS)

Ford, G. E.

1986-01-01

To characterize and quantify the performance of the Landsat thematic mapper (TM), techniques for dimensionality reduction by linear transformation have been studied and evaluated and the accuracy of the correction of geometric errors in TM images analyzed. Theoretical evaluations and comparisons for existing methods for the design of linear transformation for dimensionality reduction are presented. These methods include the discrete Karhunen Loeve (KL) expansion, Multiple Discriminant Analysis (MDA), Thematic Mapper (TM)-Tasseled Cap Linear Transformation and Singular Value Decomposition (SVD). A unified approach to these design problems is presented in which each method involves optimizing an objective function with respect to the linear transformation matrix. From these studies, four modified methods are proposed. They are referred to as the Space Variant Linear Transformation, the KL Transform-MDA hybrid method, and the First and Second Version of the Weighted MDA method. The modifications involve the assignment of weights to classes to achieve improvements in the class conditional probability of error for classes with high weights. Experimental evaluations of the existing and proposed methods have been performed using the six reflective bands of the TM data. It is shown that in terms of probability of classification error and the percentage of the cumulative eigenvalues, the six reflective bands of the TM data require only a three dimensional feature space. It is shown experimentally as well that for the proposed methods, the classes with high weights have improvements in class conditional probability of error estimates as expected.

Statistical modelling of networked human-automation performance using working memory capacity.

PubMed

Ahmed, Nisar; de Visser, Ewart; Shaw, Tyler; Mohamed-Ameen, Amira; Campbell, Mark; Parasuraman, Raja

2014-01-01

This study examines the challenging problem of modelling the interaction between individual attentional limitations and decision-making performance in networked human-automation system tasks. Analysis of real experimental data from a task involving networked supervision of multiple unmanned aerial vehicles by human participants shows that both task load and network message quality affect performance, but that these effects are modulated by individual differences in working memory (WM) capacity. These insights were used to assess three statistical approaches for modelling and making predictions with real experimental networked supervisory performance data: classical linear regression, non-parametric Gaussian processes and probabilistic Bayesian networks. It is shown that each of these approaches can help designers of networked human-automated systems cope with various uncertainties in order to accommodate future users by linking expected operating conditions and performance from real experimental data to observable cognitive traits like WM capacity. Practitioner Summary: Working memory (WM) capacity helps account for inter-individual variability in operator performance in networked unmanned aerial vehicle supervisory tasks. This is useful for reliable performance prediction near experimental conditions via linear models; robust statistical prediction beyond experimental conditions via Gaussian process models and probabilistic inference about unknown task conditions/WM capacities via Bayesian network models.

Computational and experimental model of transdermal iontophorethic drug delivery system.

PubMed

Filipovic, Nenad; Saveljic, Igor; Rac, Vladislav; Graells, Beatriz Olalde; Bijelic, Goran

2017-11-30

The concept of iontophoresis is often applied to increase the transdermal transport of drugs and other bioactive agents into the skin or other tissues. It is a non-invasive drug delivery method which involves electromigration and electroosmosis in addition to diffusion and is shown to be a viable alternative to conventional administration routs such as oral, hypodermic and intravenous injection. In this study we investigated, experimentally and numerically, in vitro drug delivery of dexamethasone sodium phosphate to porcine skin. Different current densities, delivery durations and drug loads were investigated experimentally and introduced as boundary conditions for numerical simulations. Nernst-Planck equation was used for calculation of active substance flux through equivalent model of homogeneous hydrogel and skin layers. The obtained numerical results were in good agreement with experimental observations. A comprehensive in-silico platform, which includes appropriate numerical tools for fitting, could contribute to iontophoretic drug-delivery devices design and correct dosage and drug clearance profiles as well as to perform much faster in-silico experiments to better determine parameters and performance criteria of iontophoretic drug delivery. Copyright © 2017 Elsevier B.V. All rights reserved.

Downwash and Wake Behind Plain and Flapped Airfoils

NASA Technical Reports Server (NTRS)

Silverstein, Abe; Katzoff, S; Bullivant, W Kenneth

1939-01-01

Extensive experimental measurements have been made of the downwash angles and the wake characteristics behind airfoils with and without flaps and the data have been analyzed and correlated with the theory. A detailed study was made of the errors involved in applying lifting-line theory, such as the effects of a finite wing chord, the rolling-up of the trailing vortex sheet, and the wake. The downwash angles, as computed from the theoretical span load distribution by means of the Biot-Savart equation, were found to be in satisfactory agreement with the experimental results. The rolling-up of the trailing vortex sheet may be neglected, but the vertical displacement of the vortex sheet requires consideration. By the use of a theoretical treatment indicated by Prandtl, it has been possible to generalize the available experimental results so the predictions can be made of the important wake parameters in terms of the distance behind the airfoil trailing edge and the profile-drag coefficient. The method of application of the theory to design and the satisfactory agreement between predicted and experimental results when applied to an airplane are demonstrated.

Second-order sliding mode control with experimental application.

PubMed

Eker, Ilyas

2010-07-01

In this article, a second-order sliding mode control (2-SMC) is proposed for second-order uncertain plants using equivalent control approach to improve the performance of control systems. A Proportional + Integral + Derivative (PID) sliding surface is used for the sliding mode. The sliding mode control law is derived using direct Lyapunov stability approach and asymptotic stability is proved theoretically. The performance of the closed-loop system is analysed through an experimental application to an electromechanical plant to show the feasibility and effectiveness of the proposed second-order sliding mode control and factors involved in the design. The second-order plant parameters are experimentally determined using input-output measured data. The results of the experimental application are presented to make a quantitative comparison with the traditional (first-order) sliding mode control (SMC) and PID control. It is demonstrated that the proposed 2-SMC system improves the performance of the closed-loop system with better tracking specifications in the case of external disturbances, better behavior of the output and faster convergence of the sliding surface while maintaining the stability. 2010 ISA. Published by Elsevier Ltd. All rights reserved.

Experimental hexamitiasis in juvenile coho salmon (Oncorhynchus kisutch) and steelhead trout (Salmo gairdner)

USGS Publications Warehouse

1965-01-01

An exogenous strain of cultured Hexamita salmonis (Moore) was employed to induce trophic hexamitiasis in otherwise disease-free juveniles of coho salmon (Oncorhynchus kisutch) and steelhead trout (Salmo gairdneri). Mortality and growth were the parameters used to detect the effects of hexamitiasis on the two species. Two levels of each of the three experimental factors under study, Hexamita infection, species of fish, and density of fish, were arranged in a three-way factorial design. Replicate lots involved a total of 1,440 fish held under controlled laboratory conditions.Comparisons of growth and mortality indicate that infection with H. salmonis over a period of 8 weeks is innocuous to coho salmon. Steelhead trout suffered a low, but statistically significant mortality which subsided after the sixth week; growth rate was not affected.

Assessing signal-to-noise in quantitative proteomics: multivariate statistical analysis in DIGE experiments.

PubMed

Friedman, David B

2012-01-01

All quantitative proteomics experiments measure variation between samples. When performing large-scale experiments that involve multiple conditions or treatments, the experimental design should include the appropriate number of individual biological replicates from each condition to enable the distinction between a relevant biological signal from technical noise. Multivariate statistical analyses, such as principal component analysis (PCA), provide a global perspective on experimental variation, thereby enabling the assessment of whether the variation describes the expected biological signal or the unanticipated technical/biological noise inherent in the system. Examples will be shown from high-resolution multivariable DIGE experiments where PCA was instrumental in demonstrating biologically significant variation as well as sample outliers, fouled samples, and overriding technical variation that would not be readily observed using standard univariate tests.

Thermodynamics and Mechanics of Membrane Curvature Generation and Sensing by Proteins and Lipids

PubMed Central

Baumgart, Tobias; Capraro, Benjamin R.; Zhu, Chen; Das, Sovan L.

2014-01-01

Research investigating lipid membrane curvature generation and sensing is a rapidly developing frontier in membrane physical chemistry and biophysics. The fast recent progress is based on the discovery of a plethora of proteins involved in coupling membrane shape to cellular membrane function, the design of new quantitative experimental techniques to study aspects of membrane curvature, and the development of analytical theories and simulation techniques that allow a mechanistic interpretation of quantitative measurements. The present review first provides an overview of important classes of membrane proteins for which function is coupled to membrane curvature. We then survey several mechanisms that are assumed to underlie membrane curvature sensing and generation. Finally, we discuss relatively simple thermodynamic/mechanical models that allow quantitative interpretation of experimental observations. PMID:21219150

Experimental investigation of the wake behind a model of wind turbine in a water flume

NASA Astrophysics Data System (ADS)

Okulov, V. L.; Naumov, I. N.; Kabardin, I.; Mikkelsen, R.; Sørensen, J. N.

2014-12-01

The flow behind the model of wind turbine rotor is investigated experimentally in a water flume using Particle Image Velocimetry. The study carried out involves rotors of three bladed wind turbine designed using Glauert's optimization. The transitional regime, generally characterized as in between the regime governed by stable organized vortical structures and the turbulent wake, develops from disturbances of the tip and root vorticies through vortex paring and further complex behaviour towards the fully turbulent wake. Our PIV measurements pay special attention to the onset of the instabilities. The near wake characteristics (development of expansion, tip vortex position, deficit velocity and rotation in the wake) have been measured for different tip speed ratio to compare with main assumptions and conclusions of various rotor theories.

Experimental verification of multipartite entanglement in quantum networks

PubMed Central

McCutcheon, W.; Pappa, A.; Bell, B. A.; McMillan, A.; Chailloux, A.; Lawson, T.; Mafu, M.; Markham, D.; Diamanti, E.; Kerenidis, I.; Rarity, J. G.; Tame, M. S.

2016-01-01

Multipartite entangled states are a fundamental resource for a wide range of quantum information processing tasks. In particular, in quantum networks, it is essential for the parties involved to be able to verify if entanglement is present before they carry out a given distributed task. Here we design and experimentally demonstrate a protocol that allows any party in a network to check if a source is distributing a genuinely multipartite entangled state, even in the presence of untrusted parties. The protocol remains secure against dishonest behaviour of the source and other parties, including the use of system imperfections to their advantage. We demonstrate the verification protocol in a three- and four-party setting using polarization-entangled photons, highlighting its potential for realistic photonic quantum communication and networking applications. PMID:27827361

Time-to-event continual reassessment method incorporating treatment cycle information with application to an oncology phase I trial.

PubMed

Huang, Bo; Kuan, Pei Fen

2014-11-01

Delayed dose limiting toxicities (i.e. beyond first cycle of treatment) is a challenge for phase I trials. The time-to-event continual reassessment method (TITE-CRM) is a Bayesian dose-finding design to address the issue of long observation time and early patient drop-out. It uses a weighted binomial likelihood with weights assigned to observations by the unknown time-to-toxicity distribution, and is open to accrual continually. To avoid dosing at overly toxic levels while retaining accuracy and efficiency for DLT evaluation that involves multiple cycles, we propose an adaptive weight function by incorporating cyclical data of the experimental treatment with parameters updated continually. This provides a reasonable estimate for the time-to-toxicity distribution by accounting for inter-cycle variability and maintains the statistical properties of consistency and coherence. A case study of a First-in-Human trial in cancer for an experimental biologic is presented using the proposed design. Design calibrations for the clinical and statistical parameters are conducted to ensure good operating characteristics. Simulation results show that the proposed TITE-CRM design with adaptive weight function yields significantly shorter trial duration, does not expose patients to additional risk, is competitive against the existing weighting methods, and possesses some desirable properties. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Design and fabrication of a full-scale actively controlled satellite appendage simulator unit

NASA Astrophysics Data System (ADS)

Jacobs, Jack H.; Quenon, Dan; Hadden, Steve; Self, Rick

1999-07-01

Modern satellites require the ability to slew and settle quickly in order to acquire or transmit data efficiently. Solar arrays and communication antennas cause low frequency disturbances to the satellite bus during these maneuvers causing undesirable induced vibration of the payload. The ability to develop and experimentally demonstrate attitude control laws which compensate for these flexible body disturbances is of prime importance to modern day satellite manufacturers. Honeywell has designed and fabricated an actively controlled Appendage Simulator Unit (ASU) which can physically induce the modal characteristics of satellite appendages on to a ground based satellite test bed installed on an air bearing. The ASU consists of two orthogonal fulcrum beams weighting over 800 pounds each utilizing two electrodynamic shakers to induce active torques onto the bus. The ASU is programmed with the state space characteristics of the desired appendage and responds in real time to the bus motion to generate realistic disturbances back onto the satellite. Two LVDT's are used on each fulcrum beam to close the loop and insure the system responds in real time the same way a real solar array would on-orbit. Each axis is independently programmable in order to simulate various orientations or modal contributions from an appendage. The design process for the ASU involved the optimization of sensors, actuators, control authority, weight, power and functionality. The smart structure system design process and experimental results are described in detail.

Quantifying the effect of experimental design choices for in vitro scratch assays.

PubMed

Johnston, Stuart T; Ross, Joshua V; Binder, Benjamin J; Sean McElwain, D L; Haridas, Parvathi; Simpson, Matthew J

2016-07-07

Scratch assays are often used to investigate potential drug treatments for chronic wounds and cancer. Interpreting these experiments with a mathematical model allows us to estimate the cell diffusivity, D, and the cell proliferation rate, λ. However, the influence of the experimental design on the estimates of D and λ is unclear. Here we apply an approximate Bayesian computation (ABC) parameter inference method, which produces a posterior distribution of D and λ, to new sets of synthetic data, generated from an idealised mathematical model, and experimental data for a non-adhesive mesenchymal population of fibroblast cells. The posterior distribution allows us to quantify the amount of information obtained about D and λ. We investigate two types of scratch assay, as well as varying the number and timing of the experimental observations captured. Our results show that a scrape assay, involving one cell front, provides more precise estimates of D and λ, and is more computationally efficient to interpret than a wound assay, with two opposingly directed cell fronts. We find that recording two observations, after making the initial observation, is sufficient to estimate D and λ, and that the final observation time should correspond to the time taken for the cell front to move across the field of view. These results provide guidance for estimating D and λ, while simultaneously minimising the time and cost associated with performing and interpreting the experiment. Copyright © 2016 Elsevier Ltd. All rights reserved.

Social cohesion through football: a quasi-experimental mixed methods design to evaluate a complex health promotion program.

PubMed

Nathan, Sally; Bunde-Birouste, Anne; Evers, Clifton; Kemp, Lynn; MacKenzie, Julie; Henley, Robert

2010-10-05

Social isolation and disengagement fragments local communities. Evidence indicates that refugee families are highly vulnerable to social isolation in their countries of resettlement. Research to identify approaches to best address this is needed. Football United is a program that aims to foster social inclusion and cohesion in areas with high refugee settlement in New South Wales, Australia, through skills and leadership development, mentoring, and the creation of links with local community and corporate leaders and organisations. The Social Cohesion through Football study's broad goal is to examine the implementation of a complex health promotion program, and to analyse the processes involved in program implementation. The study will consider program impact on individual health and wellbeing, social inclusion and cohesion, as well as analyse how the program by necessity interacts and adapts to context during implementation, a concept we refer to as plasticity. The proposed study will be the first prospective cohort impact study to our knowledge to assess the impact of a comprehensive integrated program using football as a vehicle for fostering social inclusion and cohesion in communities with high refugee settlement. A quasi-experimental cohort study design with treatment partitioning involving four study sites. The study employs a 'dose response' model, comparing those with no involvement in the Football United program with those with lower or higher levels of participation. A range of qualitative and quantitative measures will be used in the study. Study participants' emotional well being, resilience, ethnic identity and other group orientation, feelings of social inclusion and belonging will be measured using a survey instrument complemented by relevant data drawn from in-depth interviews, self reporting measures and participant observation. The views of key informants from the program and the wider community will also be solicited. The complexity of the Football United program poses challenges for measurement, and requires the study design to be responsive to the dynamic nature of the program and context. Assessment of change is needed at multiple levels, drawing on mixed methods and multidisciplinary approaches in implementation and evaluation. Attention to these challenges has underpinned the design and methods in the Social Cohesion through Football study, which will use a unique and innovative combination of measures that have not been applied together previously in social inclusion/cohesion and sport and social inclusion/cohesion program research.

Experimental design methods for bioengineering applications.

PubMed

Keskin Gündoğdu, Tuğba; Deniz, İrem; Çalışkan, Gülizar; Şahin, Erdem Sefa; Azbar, Nuri

2016-01-01

Experimental design is a form of process analysis in which certain factors are selected to obtain the desired responses of interest. It may also be used for the determination of the effects of various independent factors on a dependent factor. The bioengineering discipline includes many different areas of scientific interest, and each study area is affected and governed by many different factors. Briefly analyzing the important factors and selecting an experimental design for optimization are very effective tools for the design of any bioprocess under question. This review summarizes experimental design methods that can be used to investigate various factors relating to bioengineering processes. The experimental methods generally used in bioengineering are as follows: full factorial design, fractional factorial design, Plackett-Burman design, Taguchi design, Box-Behnken design and central composite design. These design methods are briefly introduced, and then the application of these design methods to study different bioengineering processes is analyzed.

75 FR 48672 - Pesticides; Revised Fee Schedule for Registration Applications

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-11

... follows B772 118 Amend or extend Experimental 3 11,577 Use Permit; minor changes to experimental design...,942 Experimental Use Permit; minor changes to experimental design; extend established temporary... revision of experimental design B780 121 New active ingredient; non- 12 144,704 food/feed; no SAP review...

The effects of using diagramming as a representational technique on high school students' achievement in solving math word problems

NASA Astrophysics Data System (ADS)

Banerjee, Banmali

Methods and procedures for successfully solving math word problems have been, and continue to be a mystery to many U.S. high school students. Previous studies suggest that the contextual and mathematical understanding of a word problem, along with the development of schemas and their related external representations, positively contribute to students' accomplishments when solving word problems. Some studies have examined the effects of diagramming on students' abilities to solve word problems that only involved basic arithmetic operations. Other studies have investigated how instructional models that used technology influenced students' problem solving achievements. Still other studies have used schema-based instruction involving students with learning disabilities. No study has evaluated regular high school students' achievements in solving standard math word problems using a diagramming technique without technological aid. This study evaluated students' achievement in solving math word problems using a diagramming technique. Using a quasi-experimental experimental pretest-posttest research design, quantitative data were collected from 172 grade 11 Hispanic English language learners (ELLS) and African American learners whose first language is English (EFLLs) in 18 classes at an inner city high school in Northern New Jersey. There were 88 control and 84 experimental students. The pretest and posttest of each participating student and samples of the experimental students' class assignments provided the qualitative data for the study. The data from this study exhibited that the diagramming method of solving math word problems significantly improved student achievement in the experimental group (p<.01) compared to the control group. The study demonstrated that urban, high school, ELLs benefited from instruction that placed emphasis on the mathematical vocabulary and symbols used in word problems and that both ELLs and EFLLs improved their problem solving success through careful attention to the creation and labeling of diagrams to represent the mathematics involved in standard word problems. Although Learnertype (ELL, EFLL), Classtype (Bilingual and Mixed), and Gender (Female, Male) were not significant indicators of student achievement, there was significant interaction between Treatment and Classtype at the level of the Bilingual students ( p<.01) and between Treatment and Learnertype at the level of the ELLs (p<.01).

Development and Validation of a Rubric for Diagnosing Students’ Experimental Design Knowledge and Difficulties

PubMed Central

Dasgupta, Annwesa P.; Anderson, Trevor R.

2014-01-01

It is essential to teach students about experimental design, as this facilitates their deeper understanding of how most biological knowledge was generated and gives them tools to perform their own investigations. Despite the importance of this area, surprisingly little is known about what students actually learn from designing biological experiments. In this paper, we describe a rubric for experimental design (RED) that can be used to measure knowledge of and diagnose difficulties with experimental design. The development and validation of the RED was informed by a literature review and empirical analysis of undergraduate biology students’ responses to three published assessments. Five areas of difficulty with experimental design were identified: the variable properties of an experimental subject; the manipulated variables; measurement of outcomes; accounting for variability; and the scope of inference appropriate for experimental findings. Our findings revealed that some difficulties, documented some 50 yr ago, still exist among our undergraduate students, while others remain poorly investigated. The RED shows great promise for diagnosing students’ experimental design knowledge in lecture settings, laboratory courses, research internships, and course-based undergraduate research experiences. It also shows potential for guiding the development and selection of assessment and instructional activities that foster experimental design. PMID:26086658

Comparative Investigation on Tool Wear during End Milling of AISI H13 Steel with Different Tool Path Strategies

NASA Astrophysics Data System (ADS)

Adesta, Erry Yulian T.; Riza, Muhammad; Avicena

2018-03-01

Tool wear prediction plays a significant role in machining industry for proper planning and control machining parameters and optimization of cutting conditions. This paper aims to investigate the effect of tool path strategies that are contour-in and zigzag tool path strategies applied on tool wear during pocket milling process. The experiments were carried out on CNC vertical machining centre by involving PVD coated carbide inserts. Cutting speed, feed rate and depth of cut were set to vary. In an experiment with three factors at three levels, Response Surface Method (RSM) design of experiment with a standard called Central Composite Design (CCD) was employed. Results obtained indicate that tool wear increases significantly at higher range of feed per tooth compared to cutting speed and depth of cut. This result of this experimental work is then proven statistically by developing empirical model. The prediction model for the response variable of tool wear for contour-in strategy developed in this research shows a good agreement with experimental work.

Spectrophotometric determination of triclosan based on diazotization reaction: response surface optimization using Box-Behnken design.

PubMed

Kaur, Inderpreet; Gaba, Sonal; Kaur, Sukhraj; Kumar, Rajeev; Chawla, Jyoti

2018-05-01

A spectrophotometric method based on diazotization of aniline with triclosan has been developed for the determination of triclosan in water samples. The diazotization process involves two steps: (1) reaction of aniline with sodium nitrite in an acidic medium to form diazonium ion and (2) reaction of diazonium ion with triclosan to form a yellowish-orange azo compound in an alkaline medium. The resulting yellowish-orange product has a maximum absorption at 352 nm which allows the determination of triclosan in aqueous solution in the linear concentration range of 0.1-3.0 μM with R 2 = 0.998. The concentration of hydrochloric acid, sodium nitrite, and aniline was optimized for diazotization reaction to achieve good spectrophotometric determination of triclosan. The optimization of experimental conditions for spectrophotometric determination of triclosan in terms of concentration of sodium nitrite, hydrogen chloride and aniline was also carried out by using Box-Behnken design of response surface methodology and results obtained were in agreement with the experimentally optimized values. The proposed method was then successfully applied for analyses of triclosan content in water samples.

Experimental Studies of the Heat Transfer to RBCC Rocket Nozzles for CFD Application to Design Methodologies

NASA Technical Reports Server (NTRS)

Santoro, Robert J.; Pal, Sibtosh

1999-01-01

Rocket thrusters for Rocket Based Combined Cycle (RBCC) engines typically operate with hydrogen/oxygen propellants in a very compact space. Packaging considerations lead to designs with either axisymmetric or two-dimensional throat sections. Nozzles tend to be either two- or three-dimensional. Heat transfer characteristics, particularly in the throat, where the peak heat flux occurs, are not well understood. Heat transfer predictions for these small thrusters have been made with one-dimensional analysis such as the Bartz equation or scaling of test data from much larger thrusters. The current work addresses this issue with an experimental program that examines the heat transfer characteristics of a gaseous oxygen (GO2)/gaseous hydrogen (GH2) two-dimensional compact rocket thruster. The experiments involved measuring the axial wall temperature profile in the nozzle region of a water-cooled gaseous oxygen/gaseous hydrogen rocket thruster at a pressure of 3.45 MPa. The wall temperature measurements in the thruster nozzle in concert with Bartz's correlation are utilized in a one-dimensional model to obtain axial profiles of nozzle wall heat flux.

Automated measurement of mouse social behaviors using depth sensing, video tracking, and machine learning.

PubMed

Hong, Weizhe; Kennedy, Ann; Burgos-Artizzu, Xavier P; Zelikowsky, Moriel; Navonne, Santiago G; Perona, Pietro; Anderson, David J

2015-09-22

A lack of automated, quantitative, and accurate assessment of social behaviors in mammalian animal models has limited progress toward understanding mechanisms underlying social interactions and their disorders such as autism. Here we present a new integrated hardware and software system that combines video tracking, depth sensing, and machine learning for automatic detection and quantification of social behaviors involving close and dynamic interactions between two mice of different coat colors in their home cage. We designed a hardware setup that integrates traditional video cameras with a depth camera, developed computer vision tools to extract the body "pose" of individual animals in a social context, and used a supervised learning algorithm to classify several well-described social behaviors. We validated the robustness of the automated classifiers in various experimental settings and used them to examine how genetic background, such as that of Black and Tan Brachyury (BTBR) mice (a previously reported autism model), influences social behavior. Our integrated approach allows for rapid, automated measurement of social behaviors across diverse experimental designs and also affords the ability to develop new, objective behavioral metrics.

Probing the effects of surface hydrophobicity and tether orientation on antibody-antigen binding

NASA Astrophysics Data System (ADS)

Bush, Derek B.; Knotts, Thomas A.

2017-04-01

Antibody microarrays have the potential to revolutionize molecular detection for many applications, but their current use is limited by poor reliability, and efforts to change this have not yielded fruitful results. One difficulty which limits the rational engineering of next-generation devices is that little is known, at the molecular level, about the antibody-antigen binding process near solid surfaces. Atomic-level structural information is scant because typical experimental techniques (X-ray crystallography and NMR) cannot be used to image proteins bound to surfaces. To overcome this limitation, this study uses molecular simulation and an advanced, experimentally validated, coarse-grain, protein-surface model to compare fab-lysozyme binding in bulk solution and when the fab is tethered to hydrophobic and hydrophilic surfaces. The results show that the tether site in the fab, as well as the surface hydrophobicity, significantly impacts the binding process and suggests that the optimal design involves tethering fabs upright on a hydrophilic surface. The results offer an unprecedented, molecular-level picture of the binding process and give hope that the rational design of protein-microarrays is possible.

Evaluation and simultaneous optimization of bio-hydrogen production using 3 2 factorial design and the desirability function

NASA Astrophysics Data System (ADS)

Cuetos, M. J.; Gómez, X.; Escapa, A.; Morán, A.

Various mixtures incorporating a simulated organic fraction of municipal solid wastes and blood from a poultry slaughterhouse were used as substrate in a dark fermentation process for the production of hydrogen. The individual and interactive effects of hydraulic retention time (HRT), solid content in the feed (%TS) and proportion of residues (%Blood) on bio-hydrogen production were studied in this work. A central composite design and response surface methodology were employed to determine the optimum conditions for the hydrogen production process. Experimental results were approximated to a second-order model with the principal effects of the three factors considered being statistically significant (P < 0.05). The production of hydrogen obtained from the experimental point at conditions close to best operability was 0.97 L Lr -1 day -1. Moreover, a desirability function was employed in order to optimize the process when a second, methanogenic, phase is coupled with it. In this last case, the optimum conditions lead to a reduction in the production of hydrogen when the optimization process involves the maximization of intermediary products.

Automated measurement of mouse social behaviors using depth sensing, video tracking, and machine learning

PubMed Central

Hong, Weizhe; Kennedy, Ann; Burgos-Artizzu, Xavier P.; Zelikowsky, Moriel; Navonne, Santiago G.; Perona, Pietro; Anderson, David J.

2015-01-01

A lack of automated, quantitative, and accurate assessment of social behaviors in mammalian animal models has limited progress toward understanding mechanisms underlying social interactions and their disorders such as autism. Here we present a new integrated hardware and software system that combines video tracking, depth sensing, and machine learning for automatic detection and quantification of social behaviors involving close and dynamic interactions between two mice of different coat colors in their home cage. We designed a hardware setup that integrates traditional video cameras with a depth camera, developed computer vision tools to extract the body “pose” of individual animals in a social context, and used a supervised learning algorithm to classify several well-described social behaviors. We validated the robustness of the automated classifiers in various experimental settings and used them to examine how genetic background, such as that of Black and Tan Brachyury (BTBR) mice (a previously reported autism model), influences social behavior. Our integrated approach allows for rapid, automated measurement of social behaviors across diverse experimental designs and also affords the ability to develop new, objective behavioral metrics. PMID:26354123

Learning Abstract Physical Concepts from Experience: Design and Use of an RC Circuit

NASA Astrophysics Data System (ADS)

Parra, Alfredo; Ordenes, Jorge; de la Fuente, Milton

2018-05-01

Science learning for undergraduate students requires grasping a great number of theoretical concepts in a rather short time. In our experience, this is especially difficult when students are required to simultaneously use abstract concepts, mathematical reasoning, and graphical analysis, such as occurs when learning about RC circuits. We present a simple experimental model in this work that allows students to easily design, build, and analyze RC circuits, thus providing an opportunity to test personal ideas, build graphical descriptions, and explore the meaning of the respective mathematical models, ultimately gaining a better grasp of the concepts involved. The result suggests that the simple setup indeed helps untrained students to visualize the essential points of this kind of circuit.

Wide range operation of advanced low NOx aircraft gas turbine combustors

NASA Technical Reports Server (NTRS)

Roberts, P. B.; Fiorito, R. J.; Butze, H. F.

1978-01-01

The paper summarizes the results of an experimental test rig program designed to define and demonstrates techniques which would allow the jet-induced circulation and vortex air blast combustors to operate stably with acceptable emissions at simulated engine idle without compromise to the low NOx emissions under the high-altitude supersonic cruise condition. The discussion focuses on the test results of the key combustor modifications for both the simulated engine idle and cruise conditions. Several range-augmentation techniques are demonstrated that allow the lean-reaction premixed aircraft gas turbine combustor to operate with low NOx emissons at engine cruise and acceptable CO and UHC levels at engine idle. These techniques involve several combinations, including variable geometry and fuel switching designs.

Model of Ni-63 battery with realistic PIN structure

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

Munson, Charles E.; Voss, Paul L.; Ougazzaden, Abdallah, E-mail: aougazza@georgiatech-metz.fr

2015-09-14

GaN, with its wide bandgap of 3.4 eV, has emerged as an efficient material for designing high-efficiency betavoltaic batteries. An important part of designing efficient betavoltaic batteries involves a good understanding of the full process, from the behavior of the nuclear material and the creation of electron-hole pairs all the way through the collection of photo-generated carriers. This paper presents a detailed model based on Monte Carlo and Silvaco for a GaN-based betavoltaic battery device, modeled after Ni-63 as an energy source. The accuracy of the model is verified by comparing it with experimental values obtained for a GaN-based p-i-nmore » structure under scanning electron microscope illumination.« less

Long-term radiation effects on GaAs solar cell characteristics

NASA Technical Reports Server (NTRS)

Heinbockel, J. H.; Doviak, M. J.

1978-01-01

This report investigates preliminary design considerations which should be considered for a space experiment involving Gallium Arsenide (GaAs) solar cells. The electron radiation effects on GaAs solar cells were conducted in a laboratory environment, and a statistical analysis of the data is presented. In order to augment the limited laboratory data, a theoretical investigation of the effect of radiation on GaAs solar cells is also developed. The results of this study are empirical prediction equations which can be used to estimate the actual damage of electrical characteristics in a space environment. The experimental and theoretical studies also indicate how GaAs solar cell parameters should be designed in order to withstand the effects of electron radiation damage.

Model of Ni-63 battery with realistic PIN structure

NASA Astrophysics Data System (ADS)

Munson, Charles E.; Arif, Muhammad; Streque, Jeremy; Belahsene, Sofiane; Martinez, Anthony; Ramdane, Abderrahim; El Gmili, Youssef; Salvestrini, Jean-Paul; Voss, Paul L.; Ougazzaden, Abdallah

2015-09-01

GaN, with its wide bandgap of 3.4 eV, has emerged as an efficient material for designing high-efficiency betavoltaic batteries. An important part of designing efficient betavoltaic batteries involves a good understanding of the full process, from the behavior of the nuclear material and the creation of electron-hole pairs all the way through the collection of photo-generated carriers. This paper presents a detailed model based on Monte Carlo and Silvaco for a GaN-based betavoltaic battery device, modeled after Ni-63 as an energy source. The accuracy of the model is verified by comparing it with experimental values obtained for a GaN-based p-i-n structure under scanning electron microscope illumination.

Quasi experimental designs in pharmacist intervention research.

PubMed

Krass, Ines

2016-06-01

Background In the field of pharmacist intervention research it is often difficult to conform to the rigorous requirements of the "true experimental" models, especially the requirement of randomization. When randomization is not feasible, a practice based researcher can choose from a range of "quasi-experimental designs" i.e., non-randomised and at time non controlled. Objective The aim of this article was to provide an overview of quasi-experimental designs, discuss their strengths and weaknesses and to investigate their application in pharmacist intervention research over the previous decade. Results In the literature quasi experimental studies may be classified into five broad categories: quasi-experimental design without control groups; quasi-experimental design that use control groups with no pre-test; quasi-experimental design that use control groups and pre-tests; interrupted time series and stepped wedge designs. Quasi-experimental study design has consistently featured in the evolution of pharmacist intervention research. The most commonly applied of all quasi experimental designs in the practice based research literature are the one group pre-post-test design and the non-equivalent control group design i.e., (untreated control group with dependent pre-tests and post-tests) and have been used to test the impact of pharmacist interventions in general medications management as well as in specific disease states. Conclusion Quasi experimental studies have a role to play as proof of concept, in the pilot phases of interventions when testing different intervention components, especially in complex interventions. They serve to develop an understanding of possible intervention effects: while in isolation they yield weak evidence of clinical efficacy, taken collectively, they help build a body of evidence in support of the value of pharmacist interventions across different practice settings and countries. However, when a traditional RCT is not feasible for logistical and/or ethical reasons researchers should endeavour to use the more robust of the quasi experimental designs.

16 CFR § 1702.10 - Human experimental data involving the testing of human subjects.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 16 Commercial Practices 2 2013-01-01 2013-01-01 false Human experimental data involving the testing of human subjects. § 1702.10 Section § 1702.10 Commercial Practices CONSUMER PRODUCT SAFETY... PREVENTION PACKAGING ACT REQUIREMENTS; PETITION PROCEDURES AND REQUIREMENTS § 1702.10 Human experimental data...

Compelled body weight shift approach in rehabilitation of individuals with chronic stroke.

PubMed

Aruin, Alexander S; Rao, Noel; Sharma, Asha; Chaudhuri, Gouri

2012-01-01

This study was designed to evaluate the effectiveness of the compelled body weight shift (CBWS) therapy approach in the rehabilitation of individuals with chronic stroke. CBWS involves a forced shift of body weight toward a person's affected side by means of a shoe insert that establishes a lift of the nonaffected lower extremity. Eighteen individuals with chronic, unilateral stroke (mean age 57.7 ± 11.9 years, with a range of 35-75 years; mean time since stroke 6.7 ± 3.9 years, with a range of 1.1-14.1 years) who showed asymmetrical stance were randomly divided into 2 groups: the experimental group received 6 weeks of physical therapy combined with CBWS therapy, and the control group received only physical therapy. Both groups underwent a battery of identical tests (Fugl-Meyer Assessment, Berg Balance Scale, weight bearing, and gait velocity) before the start of the rehabilitation intervention, following its completion, and 3 months after the end of therapy. After the intervention, weight bearing on the affected side (measured with the Balance Master) increased in the experimental group to a larger degree compared to the control group (9.7% vs 6.4%). Similarly, gait velocity increased 10.5% in the experimental group compared to the control group. Improvements in weight bearing and gait velocity were maintained in the experimental group after the 3-month retention period. The study outcome revealed that a 6-week intervention involving CBWS therapy could result in a long-lasting improvement of the symmetry of weight bearing and velocity of gait in individuals with chronic stroke.

MicroGen: a MIAME compliant web system for microarray experiment information and workflow management.

PubMed

Burgarella, Sarah; Cattaneo, Dario; Pinciroli, Francesco; Masseroli, Marco

2005-12-01

Improvements of bio-nano-technologies and biomolecular techniques have led to increasing production of high-throughput experimental data. Spotted cDNA microarray is one of the most diffuse technologies, used in single research laboratories and in biotechnology service facilities. Although they are routinely performed, spotted microarray experiments are complex procedures entailing several experimental steps and actors with different technical skills and roles. During an experiment, involved actors, who can also be located in a distance, need to access and share specific experiment information according to their roles. Furthermore, complete information describing all experimental steps must be orderly collected to allow subsequent correct interpretation of experimental results. We developed MicroGen, a web system for managing information and workflow in the production pipeline of spotted microarray experiments. It is constituted of a core multi-database system able to store all data completely characterizing different spotted microarray experiments according to the Minimum Information About Microarray Experiments (MIAME) standard, and of an intuitive and user-friendly web interface able to support the collaborative work required among multidisciplinary actors and roles involved in spotted microarray experiment production. MicroGen supports six types of user roles: the researcher who designs and requests the experiment, the spotting operator, the hybridisation operator, the image processing operator, the system administrator, and the generic public user who can access the unrestricted part of the system to get information about MicroGen services. MicroGen represents a MIAME compliant information system that enables managing workflow and supporting collaborative work in spotted microarray experiment production.

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

Effect of simulation on knowledge of advanced cardiac life support, knowledge retention, and confidence of nursing students in Jordan.

PubMed

Tawalbeh, Loai I; Tubaishat, Ahmad

2014-01-01

This study examined the effect of simulation on nursing students' knowledge of advanced cardiac life support (ACLS), knowledge retention, and confidence in applying ACLS skills. An experimental, randomized controlled (pretest-posttest) design was used. The experimental group (n = 40) attended an ACLS simulation scenario, a 4-hour PowerPoint presentation, and demonstration on a static manikin, whereas the control group (n = 42) attended the PowerPoint presentation and a demonstration only. A paired t test indicated that posttest mean knowledge of ACLS and confidence was higher in both groups. The experimental group showed higher knowledge of ACLS and higher confidence in applying ACLS, compared with the control group. Traditional training involving PowerPoint presentation and demonstration on a static manikin is an effective teaching strategy; however, simulation is significantly more effective than traditional training in helping to improve nursing students' knowledge acquisition, knowledge retention, and confidence about ACLS. Copyright 2014, SLACK Incorporated.

Challenging Density Functional Theory Calculations with Hemes and Porphyrins

PubMed Central

de Visser, Sam P.; Stillman, Martin J.

2016-01-01

In this paper we review recent advances in computational chemistry and specifically focus on the chemical description of heme proteins and synthetic porphyrins that act as both mimics of natural processes and technological uses. These are challenging biochemical systems involved in electron transfer as well as biocatalysis processes. In recent years computational tools have improved considerably and now can reproduce experimental spectroscopic and reactivity studies within a reasonable error margin (several kcal·mol−1). This paper gives recent examples from our groups, where we investigated heme and synthetic metal-porphyrin systems. The four case studies highlight how computational modelling can correctly reproduce experimental product distributions, predicted reactivity trends and guide interpretation of electronic structures of complex systems. The case studies focus on the calculations of a variety of spectroscopic features of porphyrins and show how computational modelling gives important insight that explains the experimental spectra and can lead to the design of porphyrins with tuned properties. PMID:27070578

High Resolution, High-Speed Photography, an Increasingly Prominent Diagnostic in Ballistic Research Experiments

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

Shaw, L.; Muelder, S.

1999-10-22

High resolution, high-speed photography is becoming a prominent diagnostic in ballistic experimentation. The development of high speed cameras utilizing electro-optics and the use of lasers for illumination now provide the capability to routinely obtain high quality photographic records of ballistic style experiments. The purpose of this presentation is to review in a visual manner the progress of this technology and how it has impacted ballistic experimentation. Within the framework of development at LLNL, we look at the recent history of large format high-speed photography, and present a number of photographic records that represent the state of the art at themore » time they were made. These records are primarily from experiments involving shaped charges. We also present some examples of current photographic technology, developed within the ballistic community, that has application to hydro diagnostic experimentation at large. This paper is designed primarily as an oral-visual presentation. This written portion is to provide general background, a few examples, and a bibliography.« less

Experimental study on the role of a resistor in the filter of Hall thrusters

NASA Astrophysics Data System (ADS)

Liqiu, Wei; Chunsheng, Wang; Zhongxi, Ning; Weiwei, Liu; ChaoHai, Zhang; Daren, Yu

2011-06-01

A filter is a mainly component applied to reduce the discharge current low frequency oscillation in the range of 10-100 kHz. The only form of the filter in actual use involves RLC networks, whose design originates from the 1970s, but even now, researchers are unaware of the actual primary motivations for the resistor's presence [S. Barral et al., AIAA Paper 2008-4632, 2008]. Therefore, the role of the resistor in the filter is experimentally studied and discussed through the analysis of control system and electric circuit theory. Experimental results and analysis indicate that the presence of a resistor makes the filter having the phase compensation function. The proper phase-angle and amplitude provided by the filter would increase or decrease the ion mobility and be helpful to balance the ion production in the discharge channel and then to decrease the fluctuation of the plasma density and lower the low frequency oscillation.

Desorption isotherms and isosteric heat of desorption of previously frozen raw pork meat.

PubMed

Clemente, G; Bon, J; Benedito, J; Mulet, A

2009-08-01

Some meat products involve drying previously frozen pork meat, which makes the knowledge of sorption characteristics very important for the design and management of meat dehydration processes. The sorption isotherms of raw pork meat from the Biceps femoris and Semimembranosus muscles were determined at four temperatures: 25, 30, 35 and 40°C. The experimental results were modelled using the GAB (Guggenheim, Anderson and De Boer) model. The effect of temperature was also taken into account to model the experimental sorption isotherms using four models (GAB, Oswin, Halsey and Henderson). The best results were provided by the GAB model. From the experimental sorption isotherms the isosteric heats of sorption were determined. For a moisture content higher than 0.15kgwater/kgdm, the isosteric heat of meat was similar to the latent heat of vaporization for pure water. For a lower moisture content, an increase in the isosteric heat was observed when the moisture content decreased.

The Experimental Measurement of Local and Bulk Oxygen Transport Resistances in the Catalyst Layer of Proton Exchange Membrane Fuel Cells.

PubMed

Wang, Chao; Cheng, Xiaojing; Lu, Jiabin; Shen, Shuiyun; Yan, Xiaohui; Yin, Jiewei; Wei, Guanghua; Zhang, Junliang

2017-12-07

Remarkable progress has been made in reducing the cathodic Pt loading of PEMFCs; however, a huge performance loss appears at high current densities, indicating the existence of a large oxygen transport resistance associated with the ultralow Pt loading catalyst layer. To reduce the Pt loading without sacrificing cell performance, it is essential to illuminate the oxygen transport mechanism in the catalyst layer. Toward this goal, an experimental approach to measure the oxygen transport resistance in catalyst layers is proposed and realized for the first time in this study. The measuring approach involves a dual-layer catalyst layer design, which consists of a dummy catalyst layer and a practical catalyst layer, followed by changing the thickness of dummy layer to respectively quantify the local and bulk resistances via limiting current measurements combined with linear extrapolation. The experimental results clearly reveal that the local resistance dominates the total resistance in the catalyst layer.

No Evidence of Association between Toxoplasma gondii Infection and Financial Risk Taking in Females

PubMed Central

Šebánková, Blanka; Flegr, Jaroslav; Nave, Gideon

2015-01-01

Background Past research linked Toxoplasma gondii (TG) infection in humans with neurological and mental disorders (e.g., schizophrenia, Alzheimer’s disease and attention disorders), irregularities of the dopaminergic and testosterone system, and increased likelihood of being involved in traffic accidents. Methodology/Principal Findings We test for an association between TG infection and financial decision-making (DM) using a case-control design in a sample of female Czech students (n = 79). We estimate each subject's risk attitude and loss aversion using an experimental economic task involving real monetary incentives. We find no significant evidence that either measure of decision-making is associated with TG infection. Conclusion We were unable to find evidence of an association between TG infection and financial decision-making in females. PMID:26401912

The design and application of a Transportable Inference Engine (TIE1)

NASA Technical Reports Server (NTRS)

Mclean, David R.

1986-01-01

A Transportable Inference Engine (TIE1) system has been developed by the author as part of the Interactive Experimenter Planning System (IEPS) task which is involved with developing expert systems in support of the Spacecraft Control Programs Branch at Goddard Space Flight Center in Greenbelt, Maryland. Unlike traditional inference engines, TIE1 is written in the C programming language. In the TIE1 system, knowledge is represented by a hierarchical network of objects which have rule frames. The TIE1 search algorithm uses a set of strategies, including backward chaining, to obtain the values of goals. The application of TIE1 to a spacecraft scheduling problem is described. This application involves the development of a strategies interpreter which uses TIE1 to do constraint checking.

Carboxyhemoglobin formation secondary to nitric oxide therapy in the setting of interstitial lung disease and pulmonary hypertension.

PubMed

Ruisi, Phillip; Ruisi, Michael

2011-01-01

Carbon monoxide (CO) has been widely recognized as an exogenous poison, although endogenous mechanisms for its formation involve heme-oxygenase (HO) isoforms, more specifically HO-1, in the setting of oxidative stress such as acute respiratory distress syndrome, sepsis, trauma, and nitric oxide use have been studied. In patients with refractory hypoxemia, inhaled nitric oxide (iNO) therapy is used to selectively vasodilate the pulmonary vasculature and improve ventilation-perfusion match. Inhaled nitric oxide is rapidly inactivated on binding to hemoglobin in the formation of nitrosyl- and methemoglobin in the pulmonary vasculature. Hence, inhaled nitric oxide has minimal systemic dissemination. Several experimental design studies involving lab rats have demonstrated increased levels of carboxyhemoglobin and exhaled CO as a result of nitric oxide HO-1 induction.

Estimating Intervention Effects across Different Types of Single-Subject Experimental Designs: Empirical Illustration

ERIC Educational Resources Information Center

Moeyaert, Mariola; Ugille, Maaike; Ferron, John M.; Onghena, Patrick; Heyvaert, Mieke; Beretvas, S. Natasha; Van den Noortgate, Wim

2015-01-01

The purpose of this study is to illustrate the multilevel meta-analysis of results from single-subject experimental designs of different types, including AB phase designs, multiple-baseline designs, ABAB reversal designs, and alternating treatment designs. Current methodological work on the meta-analysis of single-subject experimental designs…

Experimental Test Rig for Optimal Control of Flexible Space Robotic Arms

DTIC Science & Technology

2016-12-01

was used to refine the test bed design and the experimental workflow. Three concepts incorporated various strategies to design a robust flexible link...used to refine the test bed design and the experimental workflow. Three concepts incorporated various strategies to design a robust flexible link... designed to perform the experimentation . The first and second concepts use traditional elastic springs in varying configurations while a third uses a

Research Methods in Healthcare Epidemiology and Antimicrobial Stewardship-Quasi-Experimental Designs.

PubMed

Schweizer, Marin L; Braun, Barbara I; Milstone, Aaron M

2016-10-01

Quasi-experimental studies evaluate the association between an intervention and an outcome using experiments in which the intervention is not randomly assigned. Quasi-experimental studies are often used to evaluate rapid responses to outbreaks or other patient safety problems requiring prompt, nonrandomized interventions. Quasi-experimental studies can be categorized into 3 major types: interrupted time-series designs, designs with control groups, and designs without control groups. This methods paper highlights key considerations for quasi-experimental studies in healthcare epidemiology and antimicrobial stewardship, including study design and analytic approaches to avoid selection bias and other common pitfalls of quasi-experimental studies. Infect Control Hosp Epidemiol 2016;1-6.

Research Methods in Healthcare Epidemiology and Antimicrobial Stewardship – Quasi-Experimental Designs

PubMed Central

Schweizer, Marin L.; Braun, Barbara I.; Milstone, Aaron M.

2016-01-01

Quasi-experimental studies evaluate the association between an intervention and an outcome using experiments in which the intervention is not randomly assigned. Quasi-experimental studies are often used to evaluate rapid responses to outbreaks or other patient safety problems requiring prompt non-randomized interventions. Quasi-experimental studies can be categorized into three major types: interrupted time series designs, designs with control groups, and designs without control groups. This methods paper highlights key considerations for quasi-experimental studies in healthcare epidemiology and antimicrobial stewardship including study design and analytic approaches to avoid selection bias and other common pitfalls of quasi-experimental studies. PMID:27267457

Development of a step-down method for altering male C57BL/6 mouse housing density and hierarchical structure: Preparations for spaceflight studies

NASA Astrophysics Data System (ADS)

Scofield, David C.; Rytlewski, Jeffrey D.; Childress, Paul; Shah, Kishan; Tucker, Aamir; Khan, Faisal; Peveler, Jessica; Li, Ding; McKinley, Todd O.; Chu, Tien-Min G.; Hickman, Debra L.; Kacena, Melissa A.

2018-05-01

This study was initiated as a component of a larger undertaking designed to study bone healing in microgravity aboard the International Space Station (ISS). Spaceflight experimentation introduces multiple challenges not seen in ground studies, especially with regard to physical space, limited resources, and inability to easily reproduce results. Together, these can lead to diminished statistical power and increased risk of failure. It is because of the limited space, and need for improved statistical power by increasing sample size over historical numbers, NASA studies involving mice require housing mice at densities higher than recommended in the Guide for the Care and Use of Laboratory Animals (National Research Council, 2011). All previous NASA missions in which mice were co-housed, involved female mice; however, in our spaceflight studies examining bone healing, male mice are required for optimal experimentation. Additionally, the logistics associated with spaceflight hardware and our study design necessitated variation of density and cohort make up during the experiment. This required the development of a new method to successfully co-house male mice while varying mouse density and hierarchical structure. For this experiment, male mice in an experimental housing schematic of variable density (Spaceflight Correlate) analogous to previously established NASA spaceflight studies was compared to a standard ground based housing schematic (Normal Density Controls) throughout the experimental timeline. We hypothesized that mice in the Spaceflight Correlate group would show no significant difference in activity, aggression, or stress when compared to Normal Density Controls. Activity and aggression were assessed using a novel activity scoring system (based on prior literature, validated in-house) and stress was assessed via body weights, organ weights, and veterinary assessment. No significant differences were detected between the Spaceflight Correlate group and the Normal Density Controls in activity, aggression, body weight, or organ weight, which was confirmed by veterinary assessments. Completion of this study allowed for clearance by NASA of our bone healing experiments aboard the ISS, and our experiment was successfully launched February 19, 2017 on SpaceX CRS-10.

Development of a step-down method for altering male C57BL/6 mouse housing density and hierarchical structure: Preparations for spaceflight studies.

PubMed

Scofield, David C; Rytlewski, Jeffrey D; Childress, Paul; Shah, Kishan; Tucker, Aamir; Khan, Faisal; Peveler, Jessica; Li, Ding; McKinley, Todd O; Chu, Tien-Min G; Hickman, Debra L; Kacena, Melissa A

2018-05-01

This study was initiated as a component of a larger undertaking designed to study bone healing in microgravity aboard the International Space Station (ISS). Spaceflight experimentation introduces multiple challenges not seen in ground studies, especially with regard to physical space, limited resources, and inability to easily reproduce results. Together, these can lead to diminished statistical power and increased risk of failure. It is because of the limited space, and need for improved statistical power by increasing sample size over historical numbers, NASA studies involving mice require housing mice at densities higher than recommended in the Guide for the Care and Use of Laboratory Animals (National Research Council, 2011). All previous NASA missions in which mice were co-housed, involved female mice; however, in our spaceflight studies examining bone healing, male mice are required for optimal experimentation. Additionally, the logistics associated with spaceflight hardware and our study design necessitated variation of density and cohort make up during the experiment. This required the development of a new method to successfully co-house male mice while varying mouse density and hierarchical structure. For this experiment, male mice in an experimental housing schematic of variable density (Spaceflight Correlate) analogous to previously established NASA spaceflight studies was compared to a standard ground based housing schematic (Normal Density Controls) throughout the experimental timeline. We hypothesized that mice in the Spaceflight Correlate group would show no significant difference in activity, aggression, or stress when compared to Normal Density Controls. Activity and aggression were assessed using a novel activity scoring system (based on prior literature, validated in-house) and stress was assessed via body weights, organ weights, and veterinary assessment. No significant differences were detected between the Spaceflight Correlate group and the Normal Density Controls in activity, aggression, body weight, or organ weight, which was confirmed by veterinary assessments. Completion of this study allowed for clearance by NASA of our bone healing experiments aboard the ISS, and our experiment was successfully launched February 19, 2017 on SpaceX CRS-10. Copyright © 2018 The Committee on Space Research (COSPAR). Published by Elsevier Ltd. All rights reserved.

IFMIF: overview of the validation activities

NASA Astrophysics Data System (ADS)

Knaster, J.; Arbeiter, F.; Cara, P.; Favuzza, P.; Furukawa, T.; Groeschel, F.; Heidinger, R.; Ibarra, A.; Matsumoto, H.; Mosnier, A.; Serizawa, H.; Sugimoto, M.; Suzuki, H.; Wakai, E.

2013-11-01

The Engineering Validation and Engineering Design Activities (EVEDA) for the International Fusion Materials Irradiation Facility (IFMIF), an international collaboration under the Broader Approach Agreement between Japan Government and EURATOM, aims at allowing a rapid construction phase of IFMIF in due time with an understanding of the cost involved. The three main facilities of IFMIF (1) the Accelerator Facility, (2) the Target Facility and (3) the Test Facility are the subject of validation activities that include the construction of either full scale prototypes or smartly devised scaled down facilities that will allow a straightforward extrapolation to IFMIF needs. By July 2013, the engineering design activities of IFMIF matured with the delivery of an Intermediate IFMIF Engineering Design Report (IIEDR) supported by experimental results. The installation of a Linac of 1.125 MW (125 mA and 9 MeV) of deuterons started in March 2013 in Rokkasho (Japan). The world's largest liquid Li test loop is running in Oarai (Japan) with an ambitious experimental programme for the years ahead. A full scale high flux test module that will house ∼1000 small specimens developed jointly in Europe and Japan for the Fusion programme has been constructed by KIT (Karlsruhe) together with its He gas cooling loop. A full scale medium flux test module to carry out on-line creep measurement has been validated by CRPP (Villigen).

The Taguchi methodology as a statistical tool for biotechnological applications: a critical appraisal.

PubMed

Rao, Ravella Sreenivas; Kumar, C Ganesh; Prakasham, R Shetty; Hobbs, Phil J

2008-04-01

Success in experiments and/or technology mainly depends on a properly designed process or product. The traditional method of process optimization involves the study of one variable at a time, which requires a number of combinations of experiments that are time, cost and labor intensive. The Taguchi method of design of experiments is a simple statistical tool involving a system of tabulated designs (arrays) that allows a maximum number of main effects to be estimated in an unbiased (orthogonal) fashion with a minimum number of experimental runs. It has been applied to predict the significant contribution of the design variable(s) and the optimum combination of each variable by conducting experiments on a real-time basis. The modeling that is performed essentially relates signal-to-noise ratio to the control variables in a 'main effect only' approach. This approach enables both multiple response and dynamic problems to be studied by handling noise factors. Taguchi principles and concepts have made extensive contributions to industry by bringing focused awareness to robustness, noise and quality. This methodology has been widely applied in many industrial sectors; however, its application in biological sciences has been limited. In the present review, the application and comparison of the Taguchi methodology has been emphasized with specific case studies in the field of biotechnology, particularly in diverse areas like fermentation, food processing, molecular biology, wastewater treatment and bioremediation.