Methodological convergence of program evaluation designs.
Chacón-Moscoso, Salvador; Anguera, M Teresa; Sanduvete-Chaves, Susana; Sánchez-Martín, Milagrosa
2014-01-01
Nowadays, the confronting dichotomous view between experimental/quasi-experimental and non-experimental/ethnographic studies still exists but, despite the extensive use of non-experimental/ethnographic studies, the most systematic work on methodological quality has been developed based on experimental and quasi-experimental studies. This hinders evaluators and planners' practice of empirical program evaluation, a sphere in which the distinction between types of study is changing continually and is less clear. Based on the classical validity framework of experimental/quasi-experimental studies, we carry out a review of the literature in order to analyze the convergence of design elements in methodological quality in primary studies in systematic reviews and ethnographic research. We specify the relevant design elements that should be taken into account in order to improve validity and generalization in program evaluation practice in different methodologies from a practical methodological and complementary view. We recommend ways to improve design elements so as to enhance validity and generalization in program evaluation practice.
Zhang, Zhongheng; Ni, Hongying; Xu, Xiao
2014-08-01
Propensity score (PS) analysis has been increasingly used in critical care medicine; however, its validation has not been systematically investigated. The present study aimed to compare effect sizes in PS-based observational studies vs. randomized controlled trials (RCTs) (or meta-analysis of RCTs). Critical care observational studies using PS were systematically searched in PubMed from inception to April 2013. Identified PS-based studies were matched to one or more RCTs in terms of population, intervention, comparison, and outcome. The effect sizes of experimental treatments were compared for PS-based studies vs. RCTs (or meta-analysis of RCTs) with sign test. Furthermore, ratio of odds ratio (ROR) was calculated from the interaction term of treatment × study type in a logistic regression model. A ROR < 1 indicates greater benefit for experimental treatment in RCTs compared with PS-based studies. RORs of each comparison were pooled by using meta-analytic approach with random-effects model. A total of 20 PS-based studies were identified and matched to RCTs. Twelve of the 20 comparisons showed greater beneficial effect for experimental treatment in RCTs than that in PS-based studies (sign test P = 0.503). The difference was statistically significant in four comparisons. ROR can be calculated from 13 comparisons, of which four showed significantly greater beneficial effect for experimental treatment in RCTs. The pooled ROR was 0.71 (95% CI: 0.63, 0.79; P = 0.002), suggesting that RCTs (or meta-analysis of RCTs) were more likely to report beneficial effect for the experimental treatment than PS-based studies. The result remained unchanged in sensitivity analysis and meta-regression. In critical care literature, PS-based observational study is likely to report less beneficial effect of experimental treatment compared with RCTs (or meta-analysis of RCTs). Copyright © 2014 Elsevier Inc. All rights reserved.
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…
Web Searching: A Process-Oriented Experimental Study of Three Interactive Search Paradigms.
ERIC Educational Resources Information Center
Dennis, Simon; Bruza, Peter; McArthur, Robert
2002-01-01
Compares search effectiveness when using query-based Internet search via the Google search engine, directory-based search via Yahoo, and phrase-based query reformulation-assisted search via the Hyperindex browser by means of a controlled, user-based experimental study of undergraduates at the University of Queensland. Discusses cognitive load,…
Reliability-based structural optimization: A proposed analytical-experimental study
NASA Technical Reports Server (NTRS)
Stroud, W. Jefferson; Nikolaidis, Efstratios
1993-01-01
An analytical and experimental study for assessing the potential of reliability-based structural optimization is proposed and described. In the study, competing designs obtained by deterministic and reliability-based optimization are compared. The experimental portion of the study is practical because the structure selected is a modular, actively and passively controlled truss that consists of many identical members, and because the competing designs are compared in terms of their dynamic performance and are not destroyed if failure occurs. The analytical portion of this study is illustrated on a 10-bar truss example. In the illustrative example, it is shown that reliability-based optimization can yield a design that is superior to an alternative design obtained by deterministic optimization. These analytical results provide motivation for the proposed study, which is underway.
Effect of Computer-Based Video Games on Children: An Experimental Study
ERIC Educational Resources Information Center
Chuang, Tsung-Yen; Chen, Wei-Fan
2009-01-01
This experimental study investigated whether computer-based video games facilitate children's cognitive learning. In comparison to traditional computer-assisted instruction (CAI), this study explored the impact of the varied types of instructional delivery strategies on children's learning achievement. One major research null hypothesis was…
NASA Astrophysics Data System (ADS)
Zolfigol, Mohammad Ali; Kiafar, Mahya; Yarie, Meysam; Taherpour, Avat(Arman); Fellowes, Thomas; Nicole Hancok, Amber; Yari, Ako
2017-06-01
Experimental and computational studies in the synthesis of 2-amino-4,6-diphenylnicotinonitrile using HBF4 as an oxidizing promoter catalyst under mild and solvent free conditions were carried out. The suggested anomeric based oxidation (ABO) mechanism is supported by experimental and theoretical evidence. The theoretical study shows that the intermediate isomers with 5R- and 5S- chiral positions have suitable structures for the aromatization through an anomeric based oxidation in the final step of the mechanistic pathway.
Louisiana experimental base project : interim report No. 1.
DOT National Transportation Integrated Search
1979-11-01
The Louisiana Experimental Base Project is a research study evaluating the design/performance characteristics of three types of base courses as incorporated into comparable flexible pavement systems on a full-scale test road. Fourteen different test ...
NASA Technical Reports Server (NTRS)
Powers, E. J.; Kim, Y. C.; Hong, J. Y.; Roth, J. R.; Krawczonek, W. M.
1978-01-01
A diagnostic, based on fast Fourier-transform spectral analysis techniques, that provides experimental insight into the relationship between the experimentally observable spectral characteristics of the fluctuations and the fluctuation-induced plasma transport is described. The model upon which the diagnostic technique is based and its experimental implementation is discussed. Some characteristic results obtained during the course of an experimental study of fluctuation-induced transport in the electric field dominated NASA Lewis bumpy torus plasma are presented.
NASA Astrophysics Data System (ADS)
Tumewu, Widya Anjelia; Wulan, Ana Ratna; Sanjaya, Yayan
2017-05-01
The purpose of this study was to know comparing the effectiveness of learning using Project-based learning (PjBL) and Discovery Learning (DL) toward students metacognitive strategies on global warming concept. A quasi-experimental research design with a The Matching-Only Pretest-Posttest Control Group Design was used in this study. The subjects were students of two classes 7th grade of one of junior high school in Bandung City, West Java of 2015/2016 academic year. The study was conducted on two experimental class, that were project-based learning treatment on the experimental class I and discovery learning treatment was done on the experimental class II. The data was collected through questionnaire to know students metacognitive strategies. The statistical analysis showed that there were statistically significant differences in students metacognitive strategies between project-based learning and discovery learning.
NASA Technical Reports Server (NTRS)
Chambers, A. B.; Blackaby, J. R.; Miles, J. B.
1973-01-01
Experimental results for three subjects walking on a treadmill at exercise rates of up to 590 watts showed that thermal comfort could be maintained in a liquid cooled garment by using an automatic temperature controller based on sweat rate. The addition of head- and neck-cooling to an Apollo type liquid cooled garment increased its effectiveness and resulted in greater subjective comfort. The biothermal model of man developed in the second portion of the study utilized heat rates and exchange coefficients based on the experimental data, and included the cooling provisions of a liquid-cooled garment with automatic temperature control based on sweat rate. Simulation results were good approximations of the experimental results.
Efficacy of Group Based Learning in Learning Moral Value
ERIC Educational Resources Information Center
Singaravelu, G.
2008-01-01
The present study highlights the efficacy of Group Based Learning on cultivating moral value of the students at Standard VIII. Parallel group Experimental method was adopted in the study. Eighty students (control group = 40 students + experimental = 40 students) were selected as sample for the study. Researcher self-made achievement tool was…
ERIC Educational Resources Information Center
Ilter, Ilhan
2014-01-01
In this research, an experimental study was carried out in social studies 4th grade students to develop students' conceptual achievement and motivation to succeed academically. The study aims to investigate the effectiveness of project-based learning (PBL) in social studies. A quasi-experimental research design (pre- and posttest) was used in the…
Mechanisms of Hydrocarbon Based Polymer Etch
NASA Astrophysics Data System (ADS)
Lane, Barton; Ventzek, Peter; Matsukuma, Masaaki; Suzuki, Ayuta; Koshiishi, Akira
2015-09-01
Dry etch of hydrocarbon based polymers is important for semiconductor device manufacturing. The etch mechanisms for oxygen rich plasma etch of hydrocarbon based polymers has been studied but the mechanism for lean chemistries has received little attention. We report on an experimental and analytic study of the mechanism for etching of a hydrocarbon based polymer using an Ar/O2 chemistry in a single frequency 13.56 MHz test bed. The experimental study employs an analysis of transients from sequential oxidation and Ar sputtering steps using OES and surface analytics to constrain conceptual models for the etch mechanism. The conceptual model is consistent with observations from MD studies and surface analysis performed by Vegh et al. and Oehrlein et al. and other similar studies. Parameters of the model are fit using published data and the experimentally observed time scales.
Experimental studies on twin PTCs driven by dual piston head linear compressor
NASA Astrophysics Data System (ADS)
Gour, Abhay S.; Joy, Joewin; Sagar, Pankaj; Sudharshan, H.; Mallappa, A.; Karunanithi, R.; Jacob, S.
2017-02-01
An experimental study on pulse tube cryocooler is presented with a twin pulse tube configuration. The study is conducted with a dual piston head linear compressor design which is developed indigenously. The two identical pulse tube cryocoolers are operated by a single linear motor which generates 1800 out of phase dual pressure waves. The advantages of the configuration being the reduction in fabrication cost and the increased cooling power. The compressor is driven at a frequency of 48 Hz using indigenously developed PWM based power supply. The CFD study of pulse tube cryocooler is discussed along with the experimental cool down results. A detailed experimental and FEM based studies on the fabrication procedure of heat exchangers is conducted to ensure better heat transfer in the same.
NASA Astrophysics Data System (ADS)
Aswan, D. M.; Lufri, L.; Sumarmin, R.
2018-04-01
This research intends to determine the effect of Problem Based Learning models on students' critical thinking skills and competences. This study was a quasi-experimental research. The population of the study was the students of class VIII SMPN 1 Subdistrict Gunuang Omeh. Random sample selection is done by randomizing the class. Sample class that was chosen VIII3 as an experimental class given that treatment study based on problems and class VIII1 as control class that treatment usually given study. Instrument that used to consist of critical thinking test, cognitive tests, observation sheet of affective and psychomotor. Independent t-test and Mann Whitney U test was used for the analysis. Results showed that there was significant difference (sig <0.05) between control and experimental group. The conclusion of this study was Problem Based Learning models affected the students’ critical thinking skills and competences.
ERIC Educational Resources Information Center
Wendt, Oliver; Miller, Bridget
2012-01-01
Critical appraisal of the research literature is an essential step in informing and implementing evidence-based practice. Quality appraisal tools that assess the methodological quality of experimental studies provide a means to identify the most rigorous research suitable for evidence-based decision-making. In single-subject experimental research,…
Creative Digital Worksheet Base on Mobile Learning
NASA Astrophysics Data System (ADS)
Wibawa, S. C.; Cholifah, R.; Utami, A. W.; Nurhidayat, A. I.
2018-01-01
The student is required to understand and act in the classroom and it is very important for selecting the media learning to determine the learning outcome. An instructional media is needed to help students achieve the best learning outcome. The objectives of this study are (1) to make Android-based student worksheet, (2) to know the students’ response on Android-based student worksheet in multimedia subject, (3) to determine the student result using Android-based student worksheet. The method used was Research and Development (R&D) using post-test-only in controlled quasi-experimental group design. The subjects of the study were 2 classes, a control class and an experimental class. The results showed (1) Android-based student worksheet was categorized very good as percentage of 85%; (2) the students’ responses was categorized very good as percentage of 86.42%; (3) the experimental class results were better than control class. The average result on cognitive tests on the experimental class was 89.97 and on control class was 78.31; whether the average result on psychomotor test on the experimental class was 89.90 and on the control class was 79.83. In conclusion, student result using Android-based student worksheet was better than those without it.
Implementing Reading Strategies Based on Collaborative Learning Approach in an English Class
ERIC Educational Resources Information Center
Suwantharathip, Ornprapat
2015-01-01
The present study investigated the effects of reading strategies based on collaborative learning approach on students' reading comprehension and reading strategy use. The quasi-experimental research study was performed with two groups of students. While the control group was taught in the traditional way, the experimental group received reading…
Problem-Based Learning in the English Language Classroom
ERIC Educational Resources Information Center
Othman, Normala; Shah, Mohamed Ismail Ahamad
2013-01-01
The purpose of this study was to investigate the effects of the problem-based learning approach (PBL) on students in language classes in two areas: course content and language development. The study was conducted on 128 students, grouped into the experimental and control groups, and employed an experimental research design. The syllabus, textbook,…
Experimental Learning Enhancing Improvisation Skills
ERIC Educational Resources Information Center
Pereira Christopoulos, Tania; Wilner, Adriana; Trindade Bestetti, Maria Luisa
2016-01-01
Purpose: This study aims to present improvisation training and experimentation as an alternative method to deal with unexpected events in which structured processes do not seem to work. Design/Methodology/Approach: Based on the literature of sensemaking and improvisation, the study designs a framework and process model of experimental learning…
Effects of a Web-based course on nursing skills and knowledge learning.
Lu, Der-Fa; Lin, Zu-Chun; Li, Yun-Ju
2009-02-01
The purpose of the study was to assess the effectiveness of supplementing traditional classroom teaching with Web-based learning design when teaching intramuscular injection nursing skills. Four clusters of nursing students at a junior college in eastern Taiwan were randomly assigned to experimental and control groups. A total of 147 students (80 in the experimental group, 67 in the control group) completed the study. All participants received the same classroom lectures and skill demonstration. The experimental group interacted using a Web-based course and were able to view the content on demand. The students and instructor interacted via a chatroom, the bulletin board, and e-mail. Participants in the experimental group had significantly higher scores on both intramuscular injection knowledge and skill learning. A Web-based design can be an effective supplementing learning tool for teaching nursing knowledge and skills.
DOT National Transportation Integrated Search
2009-10-01
This report documents the results of a study that was conducted to characterize the behavior of geogrid reinforced base : course materials. The research was conducted through an experimental testing and numerical modeling programs. The : experimental...
Using inquiry-based instructional strategies in third-grade science
NASA Astrophysics Data System (ADS)
Harris, Fanicia D.
The purpose of the study was to determine if the use of inquiry-based instructional strategies as compared to traditional instructional strategies would increase third-grade students' achievement in science, based on the pretest/posttest of the school system and the Georgia Criterion-Referenced Competency Test (CRCT). Inquiry-based instruction, presented students with a question, an observation, a data set, or a hypothesis for problem solving such as scientists use when working in real-world situations. This descriptive research employed a quantitative strategy using a pretest/posttest control group design. The research compared the science academic achievement levels of one Grade 3 class [N=14] exposed to a teacher's inquiry-based instructional strategies as compared to one Grade 3 class [ N=18] exposed to a teacher's traditional instructional strategies. The study compared the science academic performance levels of third-grade students as measured by pretest/posttest mean scores from the school system-based assessment and the Georgia CRCT. Four research hypotheses were examined. Based on the overall findings from this study, both the experimental group and the control group significantly increased their mean scores from the pretests to the posttests. The amount of gain from the pretest to the posttest was significantly greater for the experimental group than the control group for pretest/posttest 1 [t(12) = 8.79, p < .01] and pretest/posttest 2 [t(12) = 9.40, p < .01]. The experimental group significantly outperformed the control group with regard to their mean number of items answered correctly on the life sciences test [t(27) = -1.95, p = .06]. Finally, the control group did not outperform the experimental group on any of the comparisons made throughout this study. The results of this study provide empirical support for the effectiveness of the use of inquiry-based learning strategies, given that the experimental group outperformed the control group on all four posttests, on the science CRCT and on the individual Science portions on the test including earth, life and physical sciences. In fact, this study was able to detect significant differences between the experimental group and the control group with regard to the degree to which the students improved from the pretests to the posttests.
ERIC Educational Resources Information Center
Lewis, Kelly M.; Sullivan, Cris M.; Bybee, Deborah
2006-01-01
This study experimentally examined the effect of a school-based emancipatory intervention on the psychological and behavioral well-being of African American adolescents. Sixty-five eighth graders in an inner-city, predominantly Black school were randomly assigned to either receive the experimental intervention or a regular Life Skills course (the…
Karataş, Zeynep; Gökçakan, Dan Zafer
2009-01-01
This study aimed to examine the effect of group-based psychodrama therapy on the level aggression in adolescents. The study included 23 students from Nezihe Yalvac Anatolian Vocational High School of Hotel Management and Tourism that had high aggression scores. Eleven of the participants (6 female, 5 male) constituted the experimental group and 12 (6 male, 6 female) were in the control group. The 34-item Aggression Scale was used to measure level of aggression. We utilized mixed pattern design including experiment-control, pre-test and post test and follow up. The experimental group participated in group-based psychodrama therapy once a week for 90 minutes, for 14 weeks in total. The Aggression Scale was administered to the experimental and control groups before and after treatment; it was additionally administered to the experimental group 16 weeks after treatment. Data were analyzed using ANCOVA and dependent samples t tests. Our analysis shows that group-based psychodrama had an effect on the experimental group in terms of total aggression, anger, hostility, and indirect aggression scores (F=65.109, F=20.175, F=18.593, F=40.987, respectively, P<.001). There was no effect of the group-based treatment on verbal or physical aggression scores. Follow-up indicated that the effect of the therapy was still measureable 16 weeks after the cessation of the therapy. Results of the present study indicate that group-based psychodrama therapy decreased the level of aggression in the experimental group. Current findings are discussed with reference to the literature. Recommendations for further research and for psychiatric counselors are provided.
A Case-Based Approach Improves Science Students' Experimental Variable Identification Skills
ERIC Educational Resources Information Center
Grunwald, Sandra; Hartman, Andrew
2010-01-01
Incorporation of experimental case studies into the laboratory curriculum increases students' abilities to identify experimental variables that affect the outcome of an experiment. Here the authors describe how such case studies were incorporated using an online course management system into a biochemistry laboratory curriculum and the assessment…
ERIC Educational Resources Information Center
Yang, Ya-Ting C.; Newby, Timothy; Bill, Robert
2008-01-01
This experimental study investigated the effectiveness of structured Web-Based Bulletin Board (WBB) discussions in improving the critical thinking (CT) skills of learners involved in veterinary distance learning, as well as their attitudes toward learning via WBBs. The two dependent variables were learners' CT skills and their attitudes toward…
Description of alpha-nucleus interaction cross sections for cosmic ray shielding studies
NASA Technical Reports Server (NTRS)
Cucinotta, Francis A.; Townsend, Lawrence W.; Wilson, John W.
1993-01-01
Nuclear interactions of high-energy alpha particles with target nuclei important for cosmic ray studies are discussed. Models for elastic, quasi-elastic, and breakup reactions are presented and compared with experimental data. Energy-dependent interaction cross sections and secondary spectra are presented based on theoretical models and the limited experimental data base.
Developing Business Management Students' Persuasive Writing through Blog-Based Peer-Feedback
ERIC Educational Resources Information Center
Sayed, Osama H.
2010-01-01
The present study attempted to investigate the effect of using blog-based peer feedback on the persuasive writing of EFL business management students at the community college in Bisha, King Khalid University, Saudi Arabia. The study used a pre-test/post-test experimental and control group design. An experimental group and a control group were…
Arshad, Muhammad Nadeem; Bibi, Aisha; Mahmood, Tariq; Asiri, Abdullah M; Ayub, Khurshid
2015-04-03
We report here a comparative theoretical and experimental study of four triazine-based hydrazone derivatives. The hydrazones are synthesized by a three step process from commercially available benzil and thiosemicarbazide. The structures of all compounds were determined by using the UV-Vis., FT-IR, NMR (1H and 13C) spectroscopic techniques and finally confirmed unequivocally by single crystal X-ray diffraction analysis. Experimental geometric parameters and spectroscopic properties of the triazine based hydrazones are compared with those obtained from density functional theory (DFT) studies. The model developed here comprises of geometry optimization at B3LYP/6-31G (d, p) level of DFT. Optimized geometric parameters of all four compounds showed excellent correlations with the results obtained from X-ray diffraction studies. The vibrational spectra show nice correlations with the experimental IR spectra. Moreover, the simulated absorption spectra also agree well with experimental results (within 10-20 nm). The molecular electrostatic potential (MEP) mapped over the entire stabilized geometries of the compounds indicated their chemical reactivates. Furthermore, frontier molecular orbital (electronic properties) and first hyperpolarizability (nonlinear optical response) were also computed at the B3LYP/6-31G (d, p) level of theory.
Hsieh, Suh-Ing; Hsu, Li-Ling; Huang, Tzu-Hsin
2016-07-01
Baccalaureate nursing students perceive research as unattractive, doubt the value of nursing research, and do not appreciate the link of research with practice. No studies have examined students' cognitive load during an evidence-based practice research course versus a traditional research course. To assess the effect of integrating constructivist theories and evidence-based practice on student cognitive load and learning performance in a research course. A true experimental study. A Registered Nurse-to-Bachelor of Science in Nursing program. Six classes of second-year students. Students were randomly allocated to the control group (two classes) or the experimental group (two classes) using cluster randomization. The control group underwent "traditional research"; the experimental group experienced "integrating evidence-based practice into research." Instruments for outcome assessment include the Cognitive Load Scale, cognitive test, team critique paper, and qualitative feedback on course satisfaction. The between-subjects effects were compared by Analysis of Covariance. The experimental group had significantly higher mental load (8.74 vs. 7.27, p<.001), mental effort (11.07 vs. 10.07, p=.009), mental efficiency (0.33 vs. -0.31, p<.001), and research knowledge (70.61 vs. 44.92, p<.001) than the control group. The experimental group had better critique paper scores in introduction (92.80%), literature review (91.70%), and assignment requirement and writing (89.40%). Some experimental learners expressed satisfaction with learning evidence-based practice (17.78%) and critiquing a research article (7.78%). Integrating evidence-based practice into a research course not only improved the research knowledge of baccalaureate nursing students, but also increased their mental load, mental effort, and mental efficiency. Additional studies may track learners' responses to different learning systems using the developed instrument to measure the three types of cognitive load. These findings may help educators design more effective and interesting curricula for integrating research and evidence-based practice into the studies of student nurses. Copyright © 2016. Published by Elsevier Ltd.
ERIC Educational Resources Information Center
Cavus, Nadire; Ibrahim, Dogan
2007-01-01
The development of collaborative studies in learning has led to a renewed interest in the field of Web-based education. In this experimental study a highly interactive and collaborative virtual teaching environment has been created by supporting Moodle LMS with collaborative learning tool GREWPtool. The aim of this experimental study has been to…
ERIC Educational Resources Information Center
Najmuldeen, Hanan A.
2017-01-01
The present study aims to evaluate the impact of educational games-based iPad applications on the development of social studies achievement and learning retention. Sample consisted of (48) sixth grade primary students in Jeddah. The author adopted Quasi-experimental design of the experimental and control groups. She also provided the teacher a…
Kokornaczyk, Maria Olga; Scherr, Claudia; Bodrova, Natalia Borisovna; Baumgartner, Stephan
2018-05-16
Methods based on phase-transition-induced pattern formation (PTPF) are increasingly used in medical research. Frequent application fields are medical diagnosis and basic research in homeopathy. Here, we present a systematic review of experimental studies concerning PTPF-based methods applied to homeopathy research. We also aimed at categorizing the PTPF methods included in this review. Experimental studies were collected from scientific databases (PubMed, Web of Science, Russian eLibrary) and from experts in the research field in question, following the PRISMA guidelines. The studies were rated according to pre-defined scientific criteria. The review included 15 experimental studies. We identified seven different PTPF methods applied in 12 experimental models. Among these methods, phase-transition was triggered through evaporation, freezing, or solution, and in most cases led to the formation of crystals. First experimental studies concerning the application of PTPF methods in homeopathic research were performed in the first half of the 20th century; however, they were not continued in the following years. Only in the last decade, different research groups re-launched the idea, introducing new experimental approaches and computerized pattern evaluation techniques. The here-identified PTPF methods are for the first time proposed to be classified as one group of methods based on the same basic physical phenomenon. Although the number of experimental studies in the area is still rather limited, the long tradition in the application of PTPF methods and the dynamics of the present developments point out the high potential of these methods and indicate that they might meet the demand for scientific methods to study potentized preparations. The Faculty of Homeopathy.
Neil H. Berg
1990-01-01
The 10 experimental forests and ranges in California administered by the Pacific Southwest Research Station, Forest Service, U.S. Department of Agriculture, are described. The purposes of these facilities, and how to request their use for approved scientific study are given, and the natural resource base, data bases, studies, and general features of each are also...
ERIC Educational Resources Information Center
Al-Zahrani, Mona Abdullah Bakheet
2011-01-01
The current study aimed at investigating the effectiveness of keyword-based instruction in enhancing English vocabulary achievement and retention of intermediate stage pupils with different working memory capacities. The study adopted a quasi experimental design employing two groups (experimental and control). The design included an independent…
ERIC Educational Resources Information Center
Tekerci, Hacer; Kandir, Adalet
2017-01-01
Purpose: This study aimed to examine the effects of the Sense-Based Science Education Program on 60-66 months old children's scientific process skills. Research Methods: In this study, which carries experimental attribute features, the pre-test/final-test/observing-test control grouped experimental pattern, and qualitative research were used.…
ERIC Educational Resources Information Center
Laforest, Sophie; Lorthios-Guilledroit, Agathe; Nour, Kareen; Parisien, Manon; Fournier, Michel; Ellemberg, Dave; Guay, Danielle; Desgagnés-Cyr, Charles-Émile; Bier, Nathalie
2017-01-01
This study examined the effects on attitudes and lifestyle behavior of "Jog your Mind," a multi-factorial community-based program promoting cognitive vitality among seniors with no known cognitive impairment. A quasi-experimental study was conducted. Twenty-three community organizations were assigned either to the experimental group…
The Effect of Brain Based Instruction on Student Achievement in Algebra I
ERIC Educational Resources Information Center
Vass, Melissa G.
2010-01-01
This quantitative quasi-experimental study examined the effect of brain-based instruction compared to teacher-centered instruction on student achievement in algebra I. A pre-test and post-test were given to a control group of 30 and experimental group of 42 before and after a unit if study in algebra I, which was taught using the two instructional…
NASA Astrophysics Data System (ADS)
Dhote, Sharvari; Yang, Zhengbao; Zu, Jean
2018-01-01
This paper presents the modeling and experimental parametric study of a nonlinear multi-frequency broad bandwidth piezoelectric vibration-based energy harvester. The proposed harvester consists of a tri-leg compliant orthoplanar spring (COPS) and multiple masses with piezoelectric plates attached at three different locations. The vibration modes, resonant frequencies, and strain distributions are studied using the finite element analysis. The prototype is manufactured and experimentally investigated to study the effect of single as well as multiple light-weight masses on the bandwidth. The dynamic behavior of the harvester with a mass at the center is modeled numerically and characterized experimentally. The simulation and experimental results are in good agreement. A wide bandwidth with three close nonlinear vibration modes is observed during the experiments when four masses are added to the proposed harvester. The current generator with four masses shows a significant performance improvement with multiple nonlinear peaks under both forward and reverse frequency sweeps.
ERIC Educational Resources Information Center
Kaplan, David
2010-01-01
In recent years, attention in the education community has focused on the need for evidenced-based research, particularly educational policies and interventions that rest on "scientifically based research". The emphasis on scientifically based research in education has led to a corresponding increase in studies designed to provide strong warrants…
Sensitive Metamaterial Sensor for Distinction of Authentic and Inauthentic Fuel Samples
NASA Astrophysics Data System (ADS)
Tümkaya, Mehmet Ali; Dinçer, Furkan; Karaaslan, Muharrem; Sabah, Cumali
2017-08-01
A metamaterial-based sensor has been realized to distinguish authentic and inauthentic fuel samples in the microwave frequency regime. Unlike the many studies in literature on metamaterial-based sensor applications, this study focuses on a compact metamaterial-based sensor operating in the X-band frequency range. Firstly, electromagnetic properties of authentic and inauthentic fuel samples were obtained experimentally in a laboratory environment. Secondly, these experimental results were used to design and create a highly efficient metamaterial-based sensor with easy fabrication characteristics and simple design structure. The experimental results for the sensor were in good agreement with the numerical ones. The proposed sensor offers a more efficient design and can be used to detect fuel and multiple other liquids in various application fields from medical to military areas in several frequency regimes.
Experimental and numerical investigations of sedimentation of porous wastewater sludge flocs.
Hriberšek, M; Zajdela, B; Hribernik, A; Zadravec, M
2011-02-01
The paper studies the properties and sedimentation characteristics of sludge flocs, as they appear in biological wastewater treatment (BWT) plants. The flocs are described as porous and permeable bodies, with their properties defined based on conducted experimental study. The derivation is based on established geometrical properties, high-speed camera data on settling velocities and non-linear numerical model, linking settling velocity with physical properties of porous flocs. The numerical model for derivation is based on generalized Stokes model, with permeability of the floc described by the Brinkman model. As a result, correlation for flocs porosity is obtained as a function of floc diameter. This data is used in establishing a CFD numerical model of sedimentation of flocs in test conditions, as recorded during experimental investigation. The CFD model is based on Euler-Lagrange formulation, where the Lagrange formulation is chosen for computation of flocs trajectories during sedimentation. The results of numerical simulations are compared with experimental results and very good agreement is observed. © 2010 Elsevier Ltd. All rights reserved.
Modeling and experimental study of resistive switching in vertically aligned carbon nanotubes
NASA Astrophysics Data System (ADS)
Ageev, O. A.; Blinov, Yu F.; Ilina, M. V.; Ilin, O. I.; Smirnov, V. A.
2016-08-01
Model of the resistive switching in vertically aligned carbon nanotube (VA CNT) taking into account the processes of deformation, polarization and piezoelectric charge accumulation have been developed. Origin of hysteresis in VA CNT-based structure is described. Based on modeling results the VACNTs-based structure has been created. The ration resistance of high-resistance to low-resistance states of the VACNTs-based structure amounts 48. The correlation the modeling results with experimental studies is shown. The results can be used in the development nanoelectronics devices based on VA CNTs, including the nonvolatile resistive random-access memory.
NASA Astrophysics Data System (ADS)
Suresha, B. L.; Sumantha, H. S.; Salman, K. Mohammed; Pramod, N. G.; Abhiram, J.
2018-04-01
The ionization potential is usually found to be less in acid and more in base. The experiment proves that the ionization potential increases on dilution of acid to base and reduces from base to acid. The potential can be tailored according to the desired properties based on our choice of acid or base. The experimental study establishes a direct relationship between pH and electric potential. This work provides theoretical insights on the need for a basic media of pH 10 in chemical thin film growth techniques called Chemical Bath Deposition Techniques.
Chimluang, Janya; Thanasilp, Sureeporn; Akkayagorn, Lanchasak; Upasen, Ratchaneekorn; Pudtong, Noppamat; Tantitrakul, Wilailuck
2017-12-01
To evaluate the effect of an intervention based on basic Buddhist principles on the spiritual well-being of patients with terminal cancer. This quasi-experimental research study had pre- and post-test control groups. The experimental group received conventional care and an intervention based on basic Buddhist principles for three consecutive days, including seven activities based on precept activities, concentration activities and wisdom activities. The control group received conventional care alone. Forty-eight patients participated in this study: 23 in the experimental group and 25 in the control group. Their mean age was 53 (standard deviation 10) years. The spiritual well-being of participants in the experimental group was significantly higher than that of participants in the control group at the second post-test (P < 0.05). An intervention based on basic Buddhist principles improved the spiritual well-being of patients with terminal cancer. This result supports the beneficial effects of implementing this type of intervention for patients with terminal cancer. Copyright © 2017 Elsevier Ltd. All rights reserved.
ERIC Educational Resources Information Center
Pahnke, Johan; Lundgren, Tobias; Hursti, Timo; Hirvikoski, Tatja
2014-01-01
Autism spectrum disorder is characterized by social impairments and behavioural inflexibility. In this pilot study, the feasibility and outcomes of a 6-week acceptance and commitment therapy-based skills training group were evaluated in a special school setting using a quasi-experimental design (acceptance and commitment therapy/school classes as…
Project-based physics labs using low-cost open-source hardware
NASA Astrophysics Data System (ADS)
Bouquet, F.; Bobroff, J.; Fuchs-Gallezot, M.; Maurines, L.
2017-03-01
We describe a project-based physics lab, which we proposed to third-year university students. These labs are based on new open-source low-cost equipment (Arduino microcontrollers and compatible sensors). Students are given complete autonomy: they develop their own experimental setup and study the physics topic of their choice. The goal of these projects is to let students to discover the reality of experimental physics. Technical specifications of the acquisition material and case studies are presented for practical implementation in other universities.
ERIC Educational Resources Information Center
Lents, Nathan H.; Cifuentes, Oscar E.
2009-01-01
This study is an experimental introduction of web-based lecture delivery into a majors-level introductory biology course. Web-based delivery, achieved through the use of prerecorded Voice-Over PowerPoint video lectures, was introduced on a limited basis to an experimental section while a control group, with the same instructor, received standard…
NASA Astrophysics Data System (ADS)
Zhu, Jun
Ru and Pt are candidate additional component for improving the high temperature properties of Ni-base superalloys. A thermodynamic description of the Ni-Al-Cr-Ru-Pt system, serving as an essential knowledge base for better alloy design and processing control, was developed in the present study by means of thermodynamic modeling coupled with experimental investigations of phase equilibria. To deal with the order/disorder transition occurring in the Ni-base superalloys, a physical sound model, Cluster/Site Approximation (CSA) was used to describe the fcc phases. The CSA offers computational advantages, without loss of accuracy, over the Cluster Variation Method (CVM) in the calculation of multicomponent phase diagrams. It has been successfully applied to fcc phases in calculating technologically important Ni-Al-Cr phase diagrams. Our effort in this study focused on the two key ternary systems: Ni-Al-Ru and Ni-Al-Pt. The CSA calculated Ni-Al-Ru ternary phase diagrams are in good agreement with the experimental results in the literature and from the current study. A thermodynamic description of quaternary Ni-Al-Cr-Ru was obtained based on the descriptions of the lower order systems and the calculated results agree with experimental data available in literature and in the current study. The Ni-Al-Pt system was thermodynamically modeled based on the limited experimental data available in the literature and obtained from the current study. With the help of the preliminary description, a number of alloy compositions were selected for further investigation. The information obtained was used to improve the current modeling. A thermodynamic description of the Ni-Al-Cr-Pt quaternary was then obtained via extrapolation from its constituent lower order systems. The thermodynamic description for Ni-base superalloy containing Al, Cr, Ru and Pt was obtained via extrapolation. It is believed to be reliable and useful to guide the alloy design and further experimental investigation.
USDA-ARS?s Scientific Manuscript database
The present experiment was conducted to study the effects of dietary Bacillus-based direct-fed microbials (DFMs) on cytokine expression patterns, intestinal intraepithelial lymphocyte (IEL) subpopulation, splenocyte proliferation, macrophage functions and resistance against experimental coccidiosis ...
Module-Based Professional Development for Teachers: A Cost-Effective Philippine Experiment
ERIC Educational Resources Information Center
San Antonio, Diosdado M.; Morales, Nelson S.; Moral, Leo S.
2011-01-01
This article examines the impact of implementing module-based professional development for teachers (MBPDT) in the Philippines. A mixed-method study, experimental design with empirical surveys and an open-ended questionnaire revealed that the experimental group of teachers had greater professional content knowledge compared with the control group…
Ding, Yongxia; Zhang, Peili
2018-06-12
Problem-based learning (PBL) is an effective and highly efficient teaching approach that is extensively applied in education systems across a variety of countries. This study aimed to investigate the effectiveness of web-based PBL teaching pedagogies in large classes. The cluster sampling method was used to separate two college-level nursing student classes (graduating class of 2013) into two groups. The experimental group (n = 162) was taught using a web-based PBL teaching approach, while the control group (n = 166) was taught using conventional teaching methods. We subsequently assessed the satisfaction of the experimental group in relation to the web-based PBL teaching mode. This assessment was performed following comparison of teaching activity outcomes pertaining to exams and self-learning capacity between the two groups. When compared with the control group, the examination scores and self-learning capabilities were significantly higher in the experimental group (P < 0.01) compared with the control group. In addition, 92.6% of students in the experimental group expressed satisfaction with the new web-based PBL teaching approach. In a large class-size teaching environment, the web-based PBL teaching approach appears to be more optimal than traditional teaching methods. These results demonstrate the effectiveness of web-based teaching technologies in problem-based learning. Copyright © 2018. Published by Elsevier Ltd.
Kim, Sunghee; Shin, Gisoo
2016-02-01
Since previous studies on simulation-based education have been focused on fundamental nursing skills for nursing students in South Korea, there is little research available that focuses on clinical nurses in simulation-based training. Further, there is a paucity of research literature related to the integration of the nursing process into simulation training particularly in the emergency nursing care of high-risk maternal and neonatal patients. The purpose of this study was to identify the effects of nursing process-based simulation on knowledge, attitudes, and skills for maternal and child emergency nursing care in clinical nurses in South Korea. Data were collected from 49 nurses, 25 in the experimental group and 24 in the control group, from August 13 to 14, 2013. This study was an equivalent control group pre- and post-test experimental design to compare the differences in knowledge, attitudes, and skills for maternal and child emergency nursing care between the experimental group and the control group. The experimental group was trained by the nursing process-based simulation training program, while the control group received traditional methods of training for maternal and child emergency nursing care. The experimental group was more likely to improve knowledge, attitudes, and skills required for clinical judgment about maternal and child emergency nursing care than the control group. Among five stages of nursing process in simulation, the experimental group was more likely to improve clinical skills required for nursing diagnosis and nursing evaluation than the control group. These results will provide valuable information on developing nursing process-based simulation training to improve clinical competency in nurses. Further research should be conducted to verify the effectiveness of nursing process-based simulation with more diverse nurse groups on more diverse subjects in the future. Copyright © 2015 Elsevier Ltd. All rights reserved.
ERIC Educational Resources Information Center
van Lier, Pol A. C.; Huizink, Anja; Vuijk, Patricia
2011-01-01
Having friends who engage in disruptive behavior in childhood may be a risk factor for childhood tobacco experimentation. This study tested the role of friends' disruptive behavior as a mediator of the effects of a classroom based intervention on children's tobacco experimentation. 433 Children (52% males) were randomly assigned to the Good…
NASA Astrophysics Data System (ADS)
Niaz, Mansoor; Aguilera, Damarys; Maza, Arelys; Liendo, Gustavo
2002-07-01
Most general chemistry courses and textbooks emphasize experimental details and lack a history and philosophy of science perspective. The objective of this study is to facilitate freshman general chemistry students' understanding of atomic structure based on the work of Thomson, Rutherford, and Bohr. It is hypothesized that classroom discussions based on arguments/counterarguments of the heuristic principles, on which these scientists based their atomic models, can facilitate students' conceptual understanding. This study is based on 160 freshman students enrolled in six sections of General Chemistry I (three sections formed part of the experimental group). All three models (Thomson, Rutherford, and Bohr) were presented to the experimental and control group students in the traditional manner, as found in most textbooks. After this, the three sections of the experimental group participated in the discussion of six items with alternative responses. Students were first asked to select a response and then participate in classroom discussions leading to arguments in favor or against the selected response and finally select a new response. Three weeks after having discussed the six items, both the experimental and control groups presented a monthly exam (based on the three models) and after another 3 weeks a semester exam. Results obtained show that given the opportunity to argue and discuss, students' understanding can go beyond the simple regurgitation of experimental details. Performance of the experimental group showed contradictions, resistances, and progressive conceptual change with considerable and consistent improvement in the last item. It is concluded that if we want our students to understand scientific progress and practice, then it is important that we include the experimental details not as a rhetoric of conclusions (Schwab, 1962, The teaching of science as enquiry, Cambridge, MA, Harward University Press; Schwab, 1974, Conflicting conceptions of curriculum, Berkeley, CA, McCutchan) but as heuristic principles (Lakatos, 1970, Criticism and the growth of knowledge, Cambridge, UK, Cambridge University Press, pp. 91-195), which were based on arguments, controversies, and interpretations of the scientists.
ERIC Educational Resources Information Center
Van Gundy, Karen; Morton, Beth A.; Liu, Hope Q.; Kline, Jennifer
2006-01-01
To explore the effects of web-based instruction (WBI) on math anxiety, the sense of mastery, and global self-esteem, we use quasi-experimental data from undergraduate statistics students in classes assigned to three study conditions, each with varied access to, and incentive for, the use of online technologies. Results suggest that when statistics…
ERIC Educational Resources Information Center
Elshirbini Abdel-fattah Al-Ashrii, Ismail Ibrahim
2011-01-01
This study aimed to examine the effectiveness of using a suggested program based on integrating the direct and indirect approaches on developing Strategic Competence skills of EFL secondary school students. The study adopted the experimental design. One group was an experimental group (using the suggested program) and another group worked as the…
ERIC Educational Resources Information Center
Aaron Price, C.; Chiu, A.
2018-01-01
We present results of an experimental study of an urban, museum-based science teacher PD programme. A total of 125 teachers and 1676 of their students in grades 4-8 were tested at the beginning and end of the school year in which the PD programme took place. Teachers and students were assessed on subject content knowledge and attitudes towards…
Yajima, Ichiro; Zou, Cunchao; Li, Xiang; Nakano, Chizuru; Omata, Yasuhiro; Kumasaka, Mayuko Y
2015-01-01
Heavy-metal pollution occurs in various environments, including water, air and soil, and has serious effects on human health. Since heavy-metal pollution in drinking water causes various diseases including skin cancer, it has become a global problem worldwide. However, there is limited information on the mechanism of development of heavy-metal-mediated disease. We performed both fieldwork and experimental studies to elucidate the levels of heavy-metal pollution and mechanisms of development of heavy-metal-related disease and to develop a novel remediation system. Our fieldwork in Bangladesh, Vietnam and Malaysia demonstrated that drinking well water in these countries was polluted with high concentrations of several heavy metals including arsenic, barium, iron and manganese. Our experimental studies based on the data from our fieldwork demonstrated that these heavy metals caused skin cancer and hearing loss. Further experimental studies resulted in the development of a novel remediation system with which toxic heavy metals were absorbed from polluted drinking water. Implementation of both fieldwork and experimental studies is important for prediction, prevention and therapy of heavy-metal-mediated diseases.
Hochlaf, Majdi; Pan, Yi; Lau, Kai-Chung; Majdi, Youssef; Poisson, Lionel; Garcia, Gustavo A; Nahon, Laurent; Al Mogren, Muneerah Mogren; Schwell, Martin
2015-02-19
For fully understanding the light-molecule interaction dynamics at short time scales, recent theoretical and experimental studies proved the importance of accurate characterizations not only of the ground (D0) but also of the electronic excited states (e.g., D1) of molecules. While ground state investigations are currently straightforward, those of electronic excited states are not. Here, we characterized the à electronic state of ionic thymine (T(+)) DNA base using explicitly correlated coupled cluster ab initio methods and state-of-the-art synchrotron-based electron/ion coincidence techniques. The experimental spectrum is composed of rich and long vibrational progressions corresponding to the population of the low frequency modes of T(+)(Ã). This work challenges previous numerous works carried out on DNA bases using common synchrotron and VUV-based photoelectron spectroscopies. We provide hence a powerful theoretical and experimental framework to study the electronic structure of ionized DNA bases that could be generalized to other medium-sized biologically relevant systems.
2017-05-01
the oxidation ones for all concentrations of oxygen studied . Similarly to the oxidation-and-growth case , the graphene edge became “non-reactive...oxidation. Effect of Graphene Curvature on the Rate of Oxidation In an earlier experimental study , Vander Wal and Tomasek [91] investigated the...well [119, 123–125]. On the experimental side, Geigle et al. [1, 126–128] have studied gas turbine combustors experimentally with high-fidelity
Pu239 Cross-Section Variations Based on Experimental Uncertainties and Covariances
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sigeti, David Edward; Williams, Brian J.; Parsons, D. Kent
2016-10-18
Algorithms and software have been developed for producing variations in plutonium-239 neutron cross sections based on experimental uncertainties and covariances. The varied cross-section sets may be produced as random samples from the multi-variate normal distribution defined by an experimental mean vector and covariance matrix, or they may be produced as Latin-Hypercube/Orthogonal-Array samples (based on the same means and covariances) for use in parametrized studies. The variations obey two classes of constraints that are obligatory for cross-section sets and which put related constraints on the mean vector and covariance matrix that detemine the sampling. Because the experimental means and covariances domore » not obey some of these constraints to sufficient precision, imposing the constraints requires modifying the experimental mean vector and covariance matrix. Modification is done with an algorithm based on linear algebra that minimizes changes to the means and covariances while insuring that the operations that impose the different constraints do not conflict with each other.« less
Interaction Effects of Simultaneous Torsional and Compressional Cyclic Loading of Sand.
1979-12-01
loading 3a AftrRACT (rwo si .v1W f9111 t "Ofslr -d IderufI ST *lack ""iha)ln experimental research program based on laboratory test studies and scaled...experimental research program based on laboratory test studies and scaled slope model tests was conducted with specimens of Monterey No. 0 sand. The principal...objective of the research was to study the effects of interactive coupling during combined compression (normal) and shear loading on the response of
ERIC Educational Resources Information Center
Düsmez, Ihsan; Barut, Yasar
2016-01-01
The research is an experimental study which has experimental and control groups, and based on pre-test, post-test, monitoring test model. Research group consists of second and third grade students of Primary School Education and Psychological Counseling undergraduate programmes in Giresun University Faculty of Educational Sciences. The research…
Effects of Experiential-Based Videos in Multi-Disciplinary Learning
ERIC Educational Resources Information Center
Jabbar, Khalid Bin Abdul; Ong, Alex; Choy, Jeanette; Lim, Lisa
2013-01-01
This study examined the use of authentic experiential-based videos in self-explanation activities on 32 polytechnic students' learning and motivation, using a mixed method quasi-experimental design. The control group analysed a set of six pre-recorded videos of a subject performing the standing broad jump (SBJ). The experimental group captured…
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…
Biophysics of cadherin adhesion.
Leckband, Deborah; Sivasankar, Sanjeevi
2012-01-01
Since the identification of cadherins and the publication of the first crystal structures, the mechanism of cadherin adhesion, and the underlying structural basis have been studied with a number of different experimental techniques, different classical cadherin subtypes, and cadherin fragments. Earlier studies based on biophysical measurements and structure determinations resulted in seemingly contradictory findings regarding cadherin adhesion. However, recent experimental data increasingly reveal parallels between structures, solution binding data, and adhesion-based biophysical measurements that are beginning to both reconcile apparent differences and generate a more comprehensive model of cadherin-mediated cell adhesion. This chapter summarizes the functional, structural, and biophysical findings relevant to cadherin junction assembly and adhesion. We emphasize emerging parallels between findings obtained with different experimental approaches. Although none of the current models accounts for all of the available experimental and structural data, this chapter discusses possible origins of apparent discrepancies, highlights remaining gaps in current knowledge, and proposes challenges for further study.
Wang, Dansheng; Wang, Qinghua; Wang, Hao; Zhu, Hongping
2016-01-01
In the electromechanical impedance (EMI) method, the PZT patch performs the functions of both sensor and exciter. Due to the high frequency actuation and non-model based characteristics, the EMI method can be utilized to detect incipient structural damage. In recent years EMI techniques have been widely applied to monitor the health status of concrete and steel materials, however, studies on application to timber are limited. This paper will explore the feasibility of using the EMI technique for damage detection in timber specimens. In addition, the conventional damage index, namely root mean square deviation (RMSD) is employed to evaluate the level of damage. On that basis, a new damage index, Mahalanobis distance based on RMSD, is proposed to evaluate the damage severity of timber specimens. Experimental studies are implemented to detect notch and hole damage in the timber specimens. Experimental results verify the availability and robustness of the proposed damage index and its superiority over the RMSD indexes. PMID:27782088
Wang, Dansheng; Wang, Qinghua; Wang, Hao; Zhu, Hongping
2016-10-22
In the electromechanical impedance (EMI) method, the PZT patch performs the functions of both sensor and exciter. Due to the high frequency actuation and non-model based characteristics, the EMI method can be utilized to detect incipient structural damage. In recent years EMI techniques have been widely applied to monitor the health status of concrete and steel materials, however, studies on application to timber are limited. This paper will explore the feasibility of using the EMI technique for damage detection in timber specimens. In addition, the conventional damage index, namely root mean square deviation (RMSD) is employed to evaluate the level of damage. On that basis, a new damage index, Mahalanobis distance based on RMSD, is proposed to evaluate the damage severity of timber specimens. Experimental studies are implemented to detect notch and hole damage in the timber specimens. Experimental results verify the availability and robustness of the proposed damage index and its superiority over the RMSD indexes.
NASA Astrophysics Data System (ADS)
Arsal, Zeki
2017-07-01
In the study, the impact of inquiry-based learning on pre-service teachers' critical thinking dispositions was investigated. The sample of the study comprised of 56 pre-service teachers in the science education teacher education programme at the public university in the north of Turkey. In the study, quasi-experimental design with an experimental and a control group were applied to find out the impact of inquiry-based learning on the critical thinking dispositions of the pre-service teachers in the teacher education programme. The results showed that the pre-service teachers in the experimental group did not show statistically significant greater progress in terms of critical thinking dispositions than those in the control group. Teacher educators who are responsible for pedagogical courses in the teacher education programme should consider that the inquiry-based learning could not be effective method to improve pre-service teachers' critical thinking dispositions. The results are discussed in relation to potential impact on science teacher education and implications for future research.
Research on Hygiene Based on Fieldwork and Experimental Studies.
Yajima, Ichiro
2017-01-01
Several experimental studies on hygiene have recently been performed and fieldwork studies are also important and essential tools. However, the implementation of experimental studies is insufficient compared with that of fieldwork studies on hygiene. Here, we show our well-balanced implementation of both fieldwork and experimental studies of toxic-element-mediated diseases including skin cancer and hearing loss. Since the pollution of drinking well water by toxic elements induces various diseases including skin cancer, we performed both fieldwork and experimental studies to determine the levels of toxic elements and the mechanisms behind the development of toxic-element-related diseases and to develop a novel remediation system. Our fieldwork studies in several countries including Bangladesh, Vietnam and Malaysia demonstrated that drinking well water was polluted with high concentrations of several toxic elements including arsenic, barium, iron and manganese. Our experimental studies using the data from our fieldwork studies demonstrated that these toxic elements caused skin cancer and hearing loss. Further experimental studies resulted in the development of a novel remediation system that adsorbs toxic elements from polluted drinking water. A well-balanced implementation of both fieldwork and experimental studies is important for the prediction, prevention and therapy of toxic-element-mediated diseases.
van Steenbergen, Henk; Bocanegra, Bruno R
2016-12-01
In a recent letter, Plant (2015) reminded us that proper calibration of our laboratory experiments is important for the progress of psychological science. Therefore, carefully controlled laboratory studies are argued to be preferred over Web-based experimentation, in which timing is usually more imprecise. Here we argue that there are many situations in which the timing of Web-based experimentation is acceptable and that online experimentation provides a very useful and promising complementary toolbox to available lab-based approaches. We discuss examples in which stimulus calibration or calibration against response criteria is necessary and situations in which this is not critical. We also discuss how online labor markets, such as Amazon's Mechanical Turk, allow researchers to acquire data in more diverse populations and to test theories along more psychological dimensions. Recent methodological advances that have produced more accurate browser-based stimulus presentation are also discussed. In our view, online experimentation is one of the most promising avenues to advance replicable psychological science in the near future.
Active-learning versus teacher-centered instruction for learning acids and bases
NASA Astrophysics Data System (ADS)
Acar Sesen, Burcin; Tarhan, Leman
2011-07-01
Background and purpose: Active-learning as a student-centered learning process has begun to take more interest in constructing scientific knowledge. For this reason, this study aimed to investigate the effectiveness of active-learning implementation on high-school students' understanding of 'acids and bases'. Sample The sample of this study was 45 high-school students (average age 17 years) from two different classes, which were randomly assigned to the experimental (n = 21) and control groups (n = 25), in a high school in Turkey. Design and methods A pre-test consisting of 25 items was applied to both experimental and control groups before the treatment in order to identify student prerequisite knowledge about their proficiency for learning 'acids and bases'. A one-way analysis of variance (ANOVA) was conducted to compare the pre-test scores for groups and no significant difference was found between experimental (ME = 40.14) and control groups (MC = 41.92) in terms of mean scores (F 1,43 = 2.66, p > 0.05). The experimental group was taught using an active-learning curriculum developed by the authors and the control group was taught using traditional course content based on teacher-centered instruction. After the implementation, 'Acids and Bases Achievement Test' scores were collected for both groups. Results ANOVA results showed that students' 'Acids and Bases Achievement Test' post-test scores differed significantly in terms of groups (F 1,43 = 102.53; p < 0.05). Additionally, in this study 54 misconceptions, 14 of them not reported in the literature before, were observed in the following terms: 'acid and base theories'; 'metal and non-metal oxides'; 'acid and base strengths'; 'neutralization'; 'pH and pOH'; 'hydrolysis'; 'acid-base equilibrium'; 'buffers'; 'indicators'; and 'titration'. Based on the achievement test and individual interview results, it was found that high-school students in the experimental group had fewer misconceptions and understood the concepts more meaningfully than students in control group. Conclusion The study revealed that active-learning implementation is more effective at improving students' learning achievement and preventing misconceptions.
Carvalho, Fabíola G; Negrini, Thais De Cássia; Sacramento, Luis Victor S; Hebling, Josimeri; Spolidorio, Denise M P; Duque, Cristiane
2011-01-01
The objective of this study was to evaluate the antimicrobial activity of six toothpastes for infants: 3 fluoride-free experimental toothpastes--cashew-based, mango-based and without plant extract and fluoride compared with 2 commercially fluoride-free toothpastes and 1 fluoridated toothpastes. Six toothpastes for infants were evaluated in this study: (1) experimental cashew-based toothpaste; (2) experimental mango-based toothpaste; (3) experimental toothpaste without plant extract and fluoride (negative control); (4) First Teeth brand toothpaste; (5) Weleda brand toothpaste; and (6) Tandy brand toothpaste (positive control). The antimicrobial activity was recorded against Streptococcus mutans, Streptococcus sobrinus, Lactobacillus acidophilus, and Candida albicans using the agar plate diffusion test. First Teeth, Weleda, mango-based toothpaste, and toothpaste without plant extract presented no antimicrobial effect against any of the tested micro-organisms. Cashew toothpaste had antimicrobial activity against S mutans, S sobrinus, and L acidophilus, but it showed no antimicrobial activity against C albicans. There was no statistical difference between the inhibition halo of cashew and Tandy toothpastes against S mutans and L acidophilus. Cashew fluoride-free toothpaste had inhibitory activity against Streptococcus mutans and Lactobacillus acidophilus, and these results were similar to those obtained for fluoridated toothpaste.
Efficacy of a Home-Based Exercise Program After Thyroidectomy for Thyroid Cancer Patients.
Kim, Kyunghee; Gu, Mee Ock; Jung, Jung Hwa; Hahm, Jong Ryeal; Kim, Soo Kyoung; Kim, Jin Hyun; Woo, Seung Hoon
2018-02-01
The objective of this study was to determine the effect of a home-based exercise program on fatigue, anxiety, quality of life (QoL), and immune function of thyroid cancer patients taking thyroid hormone replacement after thyroidectomy. This quasi-experimental study with a non-equivalent control group included 43 outpatients taking thyroid hormone replacement after thyroidectomy (22 in the experimental group and 21 in the control group). After education about the home-based exercise program, subjects in the experimental group underwent 12 weeks of aerobic, resistance, and flexibility exercise. A comparative analysis was conducted between the two groups. Patients in the experimental group were significantly less fatigued or anxious (p < 0.01). They reported significantly improved QoL (p < 0.05) compared to those in the control group. Natural killer cell activity was significantly higher in the exercise group compared to that in the control group (p < 0.05). A home-based exercise program is effective in reducing fatigue and anxiety, improving QoL, and increasing immune function in patients taking thyroid hormone replacement after thyroidectomy. Therefore, such a home-based exercise program can be used as an intervention for patients who are taking thyroid hormone replacement after thyroidectomy.
NASA Astrophysics Data System (ADS)
Zhang, Chongfu; Qiu, Kun; Zhou, Heng; Ling, Yun; Wang, Yawei; Xu, Bo
2010-03-01
In this paper, the tunable multiple optical orthogonal codes sequences (MOOCS)-based optical label for optical packet switching (OPS) (MOOCS-OPS) is experimentally demonstrated for the first time. The tunable MOOCS-based optical label is performed by using fiber Bragg grating (FBG)-based optical en/decoders group and optical switches configured by using Field Programmable Gate Array (FPGA), and the optical label is erased by using Semiconductor Optical Amplifier (SOA). Some waveforms of the MOOCS-based optical label, optical packet including the MOOCS-based optical label and the payloads are obtained, the switching control mechanism and the switching matrix are discussed, the bit error rate (BER) performance of this system is also studied. These experimental results show that the tunable MOOCS-OPS scheme is effective.
Experimental design and quantitative analysis of microbial community multiomics.
Mallick, Himel; Ma, Siyuan; Franzosa, Eric A; Vatanen, Tommi; Morgan, Xochitl C; Huttenhower, Curtis
2017-11-30
Studies of the microbiome have become increasingly sophisticated, and multiple sequence-based, molecular methods as well as culture-based methods exist for population-scale microbiome profiles. To link the resulting host and microbial data types to human health, several experimental design considerations, data analysis challenges, and statistical epidemiological approaches must be addressed. Here, we survey current best practices for experimental design in microbiome molecular epidemiology, including technologies for generating, analyzing, and integrating microbiome multiomics data. We highlight studies that have identified molecular bioactives that influence human health, and we suggest steps for scaling translational microbiome research to high-throughput target discovery across large populations.
ERIC Educational Resources Information Center
Sen, Ceylan; Sezen Vekli, Gülsah
2016-01-01
The aim of this study is to determine the influence of inquiry-based teaching approach on pre-service science teachers' laboratory self-efficacy perceptions and scientific process skills. The quasi experimental model with pre-test-post-test control group design was used as an experimental design in this research. The sample of this study included…
ERIC Educational Resources Information Center
Pekdogan, Serpil
2016-01-01
The aim of this study is to investigate the effect of Story-Based Social Skills Training Program on the social skill development of 5-6 year-old children. In the study, the pre-test/post-test and retention test experimental design with a control group was used. 5-6 year-old 60 (30 experimental, 30 control) preschool children participated in the…
Effect of processing parameters on FDM process
NASA Astrophysics Data System (ADS)
Chari, V. Srinivasa; Venkatesh, P. R.; Krupashankar, Dinesh, Veena
2018-04-01
This paper focused on the process parameters on fused deposition modeling (FDM). Infill, resolution, temperature are the process variables considered for experimental studies. Compression strength, Hardness test microstructure are the outcome parameters, this experimental study done based on the taguchi's L9 orthogonal array is used. Taguchi array used to build the 9 different models and also to get the effective output results on the under taken parameters. The material used for this experimental study is Polylactic Acid (PLA).
ERIC Educational Resources Information Center
Cummings, Anne R.; Carr, James E.; LeBlanc, Linda A.
2012-01-01
The Picture Exchange Communication System (PECS) is a picture-based alternative communication method that is widely accepted and utilized with individuals with disabilities. Although prior studies have examined the clinical efficacy of PECS, none have experimentally evaluated its manualized training structure. We experimentally evaluated the…
USDA-ARS?s Scientific Manuscript database
For the purpose of developing an improved experimental model for studies of foot-and-mouth disease virus (FMDV) infection in cattle, three different experimental systems based on natural or simulated-natural virus exposure were compared under standardized experimental conditions. Antemortem infecti...
Experimental study of Cu-water nanofluid forced convective flow inside a louvered channel
NASA Astrophysics Data System (ADS)
Khoshvaght-Aliabadi, M.; Hormozi, F.; Zamzamian, A.
2015-03-01
Heat transfer enhancement plays a very important role for energy saving in plate-fin heat exchangers. In the present study, the influences of simultaneous utilization of a louvered plate-fin channel and copper-base deionized water nanofluid on performance of these exchangers are experimentally explored. The effects of flow rate (2-5 l/min) and nanoparticles weight fraction (0-0.4 %) on heat transfer and pressure drop characteristics are determined. Experimental results indicate that the use of louvered channel instead of the plain one can improve the heat transfer performance. Likewise, addition of small amounts of copper nanoparticles to the base fluid augments the convective heat transfer coefficient remarkably. The maximum rise of 21.7 % in the convective heat transfer coefficient is observed for the 0.4 % wt nanofluid compared to the base fluid. Also, pumping power for the base fluid and nanofluids are calculated based on the measured pressure drop in the louvered channel. The average increase in pumping power is 11.8 % for the nanofluid with 0.4 % wt compared to the base fluid. Applied performance criterion shows a maximum performance index of 1.167 for the nanofluid with 0.1 % wt Finally, two correlations are proposed for Nusselt number and friction factor which fit the experimental data with in ±10 %.
Yoo, Moon-Sook; Park, Hyung-Ran
2015-06-01
The purpose of this study was to explore the effects of case-based learning on communication skills, problem-solving ability, and learning motivation in sophomore nursing students. In this prospective, quasi-experimental study, we compared the pretest and post-test scores of an experimental group and a nonequivalent, nonsynchronized control group. Both groups were selected using convenience sampling, and consisted of students enrolled in a health communication course in the fall semesters of 2011 (control group) and 2012 (experimental group) at a nursing college in Suwon, South Korea. The two courses covered the same material, but in 2011 the course was lecture-based, while in 2012, lectures were replaced by case-based learning comprising five authentic cases of patient-nurse communication. At post-test, the case-based learning group showed significantly greater communication skills, problem-solving ability, and learning motivation than the lecture-based learning group. This finding suggests that case-based learning is an effective learning and teaching method. © 2014 Wiley Publishing Asia Pty Ltd.
Exploiting Defect Clustering to Screen Bare Die for Infant Mortality Failure: An Experimental Study
NASA Technical Reports Server (NTRS)
Lakin, David R., II; Singh, Adit D.
1999-01-01
We present the first experimental results to establish that a binning strategy based on defect clustering can be used to screen bare die for early life failures. The data for this study comes from the SEMATECH test methods experiment.
Catalyst and Fuel Interactions to Optimize Endothermic Cooling
2016-08-30
research , special, group study, etc. 3. DATES COVERED. Indicate the time during which the work was performed and the report was written, e.g., Jun 1997...information from the experimental measurements. In close collaboration with experimental group of Anderson, we completed theoretical studies on the effect...observed shifts. 3. Methane Activation by Controlling s- and d-states in Iron-based Single Site Catalysts In a recent experimental finding Guo et
NASA Astrophysics Data System (ADS)
Çam, Aylin; Geban, Ömer
2011-02-01
The purpose of the study was to investigate the effectiveness of case-based learning instruction over traditionally designed chemistry instruction on eleventh grade students' epistemological beliefs and their attitudes toward chemistry as a school subject. The subjects of this study consisted of 63 eleventh grade students from two intact classes of an urban high school instructed with same teacher. Each teaching method was randomly assigned to one class. The experimental group received case-based learning and the control group received traditional instruction. At the experimental group, life cases were presented with small group format; at the control group, lecturing and discussion was carried out. The results showed that there was a significant difference between the experimental and control group with respect to their epistemological beliefs and attitudes toward chemistry as a school subject in favor of case-based learning method group. Thus, case base learning is helpful for development of students' epistemological beliefs and attitudes toward chemistry.
Theoretical and experimental characterization of the DUal-BAse transistor (DUBAT)
NASA Astrophysics Data System (ADS)
Wu, Chung-Yu; Wu, Ching-Yuan
1980-11-01
A new A-type integrated voltage controlled differential negative resistance device using an extra effective base region to form a lateral pnp (npn) bipolar transistor beside the original base region of a vertical npn (pnp) bipolar junction transistor, and so called the DUal BAse Transistor (DUBAT), is studied both experimentally and theoretically, The DUBAT has three terminals and is fully comparible with the existing bipolar integrated circuits technologies. Based upon the equivalent circuit of the DUBAT, a simple first-order analytical theory is developed, and important device parameters, such as: the I-V characteristic, the differential negative resistance, and the peak and valley points, are also characterized. One of the proposed integrated structures of the DUBAT, which is similar in structure to I 2L but with similar high density and a normally operated vertical npn transistor, has been successfully fabricated and studied. Comparisons between the experimental data and theoretical analyses are made, and show in satisfactory agreements.
NASA Astrophysics Data System (ADS)
Syifahayu
2017-02-01
The study was conducted based on teaching and learning problems led by conventional method that had been done in the process of learning science. It gave students lack opportunities to develop their competence and thinking skills. Consequently, the process of learning science was neglected. Students did not have opportunity to improve their critical attitude and creative thinking skills. To cope this problem, the study was conducted using Project-Based Learning model through inquiry-based science education about environment. The study also used an approach called Sains Lingkungan and Teknologi masyarakat - “Saling Temas” (Environmental science and Technology in Society) which promoted the local content in Lampung as a theme in integrated science teaching and learning. The study was a quasi-experimental with pretest-posttest control group design. Initially, the subjects were given a pre-test. The experimental group was given inquiry learning method while the control group was given conventional learning. After the learning process, the subjects of both groups were given post-test. Quantitative analysis was performed using the Mann-Whitney U-test and also a qualitative descriptive. Based on the result, environmental literacy skills of students who get inquiry learning strategy, with project-based learning model on the theme soil washing, showed significant differences. The experimental group is better than the control group. Data analysis showed the p-value or sig. (2-tailed) is 0.000 <α = 0.05 with the average N-gain of experimental group is 34.72 and control group is 16.40. Besides, the learning process becomes more meaningful.
ERIC Educational Resources Information Center
Toker, Betül; Avci, Rasit
2015-01-01
This study examined the effectiveness of a cognitive-behavioral theory (CBT) psycho-educational group program on the academic procrastination behaviors of university students and the persistence of any training effect. This was a quasi-experimental research based on an experimental and control group pretest, posttest, and followup test model.…
ERIC Educational Resources Information Center
Gundogdu, Rezzan
2012-01-01
The purpose of this quasi-experimental research is to study the effects of the creative drama-based assertiveness program (CDBAP) on the assertiveness skill of Psychological Counselling and Guidance (PCG) department students. The opinions of experimental group students on the program were obtained through the CDBAP evaluation form. The sample of…
ERIC Educational Resources Information Center
Braiden, Hannah Jane; McDaniel, Benny; McCrudden, Eunan; Janes, Michele; Crozier, Barbara
2012-01-01
This study used a pre-experimental and post-experimental design to evaluate a TEACCH-based Early Intervention Programme. Thirty-one parents of 18 preschool children recently diagnosed with an Autistic Spectrum Disorder attended the eight-week programme delivered by trained facilitators. Parents completed pre-intervention and post-intervention…
Tsai, Yi-Jing; Hsu, Yu-Yun; Hou, Ting-Wei; Chang, Chiung-Hsin
2018-03-01
Women may experience significant stress during pregnancy, and antenatal care and education provide a means to address this. E-health, the use of computer and information technology for health care, has been incorporated into antenatal care and education, but e-health has not been evaluated for its usefulness in addressing stress. The objective of this study was to investigate the effectiveness of a web-based antenatal care and education system on pregnancy-related stress, general self-efficacy, and satisfaction with antenatal care. A quasi-experimental design enrolled pregnant women at 16 to 24 weeks' gestation with a low-risk pregnancy. Women in the control group (n = 67) received routine antenatal care; women in the experimental group (n = 68) also received a web-based antenatal care and education program in the second trimester. Pregnancy stress and general self-efficacy were assessed at study entry and again at 36 to 38 weeks' gestation; satisfaction with care was assessed at the study endpoint. When the pretest scores were controlled, the women in the experimental group reported significantly lower pregnancy-related stress (F = 12.9, P < .001) and significantly higher self-efficacy (F = 17.61, P < .001) than did the women in the control group. Women in the experimental group reported lower pregnancy-related stress (t = 5.09, P < .001) and a higher general self-efficacy (t = -3.17, P = .001) at posttest compared to pretest. However, the women in the control group reported a lower general self-efficacy at posttest compared to pretest (t = 2.86, P = .006). Women in the experimental group reported significantly higher satisfaction levels with antenatal care than those in the control group. A web-based antenatal care and education system can improve pregnancy-related stress and general self-efficacy among pregnant women. Integrating health care with web-based or internet-based interventions may improve the quality of antenatal care. © 2018 by the American College of Nurse-Midwives.
Helgason, Benedikt; Viceconti, Marco; Rúnarsson, Tómas P; Brynjólfsson, Sigurour
2008-01-01
Pushout tests can be used to estimate the shear strength of the bone implant interface. Numerous such experimental studies have been published in the literature. Despite this researchers are still some way off with respect to the development of accurate numerical models to simulate implant stability. In the present work a specific experimental pushout study from the literature was simulated using two different bones implant interface models. The implant was a porous coated Ti-6Al-4V retrieved 4 weeks postoperatively from a dog model. The purpose was to find out which of the interface models could replicate the experimental results using physically meaningful input parameters. The results showed that a model based on partial bone ingrowth (ingrowth stability) is superior to an interface model based on friction and prestressing due to press fit (initial stability). Even though the present study is limited to a single experimental setup, the authors suggest that the presented methodology can be used to investigate implant stability from other experimental pushout models. This would eventually enhance the much needed understanding of the mechanical response of the bone implant interface and help to quantify how implant stability evolves with time.
A new scenario-based approach to damage detection using operational modal parameter estimates
NASA Astrophysics Data System (ADS)
Hansen, J. B.; Brincker, R.; López-Aenlle, M.; Overgaard, C. F.; Kloborg, K.
2017-09-01
In this paper a vibration-based damage localization and quantification method, based on natural frequencies and mode shapes, is presented. The proposed technique is inspired by a damage assessment methodology based solely on the sensitivity of mass-normalized experimental determined mode shapes. The present method differs by being based on modal data extracted by means of Operational Modal Analysis (OMA) combined with a reasonable Finite Element (FE) representation of the test structure and implemented in a scenario-based framework. Besides a review of the basic methodology this paper addresses fundamental theoretical as well as practical considerations which are crucial to the applicability of a given vibration-based damage assessment configuration. Lastly, the technique is demonstrated on an experimental test case using automated OMA. Both the numerical study as well as the experimental test case presented in this paper are restricted to perturbations concerning mass change.
Numerical and experimental study of electron-beam coatings with modifying particles FeB and FeTi
NASA Astrophysics Data System (ADS)
Kryukova, Olga; Kolesnikova, Kseniya; Gal'chenko, Nina
2016-07-01
An experimental study of wear-resistant composite coatings based on titanium borides synthesized in the process of electron-beam welding of components thermo-reacting powders are composed of boron-containing mixture. A model of the process of electron beam coating with modifying particles of boron and titanium based on physical-chemical transformations is supposed. The dissolution process is described on the basis of formal kinetic approach. The result of numerical solution is the phase and chemical composition of the coating under nonequilibrium conditions, which is one of the important characteristics of the coating forming during electron beam processing. Qualitative agreement numerical calculations with experimental data was shown.
NASA Astrophysics Data System (ADS)
Hamed Mashhadzadeh, A.; Fereidoon, Ab.; Ghorbanzadeh Ahangari, M.
2017-10-01
In current study we combined theoretical and experimental studies to evaluate the effect of functionalization and silanization on mechanical behavior of polymer-based/CNT nanocomposites. Epoxy was selected as thermoset polymer, polypropylene and poly vinyl chloride were selected as thermoplastic polymers. The whole procedure is divided to two sections . At first we applied density functional theory (DFT) to analyze the effect of functionalization on equilibrium distance and adsorption energy of unmodified, functionalized by sbnd OH group and silanized epoxy/CNT, PP/CNT and PVC/CNT nanocomposites and the results showed that functionalization increased adsorption energy and reduced the equilibrium distance in all studied nanocomposites and silanization had higher effect comparing to OH functionalizing. Then we prepared experimental samples of all mentioned nanocomposites and tested their tensile and flexural strength properties. The obtained results showed that functionalization increased the studied mechanical properties in all evaluated nanocomposites. Finally we compared the results of experimental and theoretical sections with each other and estimated a suitable agreement between these parts.
DOT National Transportation Integrated Search
1979-01-01
The objective of this study was to investigate the resistance of field concretes containing fly ash to damage from cycles of freezing and thawing as evidenced by scaling, based upon a reevaluation of a field project. In 1955 and 1956 an experimental ...
CALL, Prewriting Strategies, and EFL Writing Quantity
ERIC Educational Resources Information Center
Shafiee, Sajad; Koosha, Mansour; Afghar, Akbar
2015-01-01
This study sought to explore the effect of teaching prewriting strategies through different methods of input delivery (i.e. conventional, web-based, and hybrid) on EFL learners' writing quantity. In its quasi-experimental study, the researchers recruited 98 available sophomores, and assigned them to three experimental groups (conventional,…
Hinkle, Joshua C; Weisburd, David; Famega, Christine; Ready, Justin
2013-01-01
Hot spots policing is one of the most influential police innovations, with a strong body of experimental research showing it to be effective in reducing crime and disorder. However, most studies have been conducted in major cities, and we thus know little about whether it is effective in smaller cities, which account for a majority of police agencies. The lack of experimental studies in smaller cities is likely in part due to challenges designing statistically powerful tests in such contexts. The current article explores the challenges of statistical power and "noise" resulting from low base rates of crime in smaller cities and provides suggestions for future evaluations to overcome these limitations. Data from a randomized experimental evaluation of broken windows policing in hot spots are used to illustrate the challenges that low base rates present for evaluating hot spots policing programs in smaller cities. Analyses show low base rates make it difficult to detect treatment effects. Very large effect sizes would be required to reach sufficient power, and random fluctuations around low base rates make detecting treatment effects difficult, irrespective of power, by masking differences between treatment and control groups. Low base rates present strong challenges to researchers attempting to evaluate hot spots policing in smaller cities. As such, base rates must be taken directly into account when designing experimental evaluations. The article offers suggestions for researchers attempting to expand the examination of hot spots policing and other microplace-based interventions to smaller jurisdictions.
ERIC Educational Resources Information Center
Wongpinunwatana, Nitaya
2013-01-01
This study examined the use and effect of a role-playing game on learners' ability in information systems audit. The study is based on experimental research. Information systems control and audit case study and video had been developed. A total of 75 graduate students undertaking a Master's degree in accounting participated in the experiment. The…
Dimensional Comparisons: An Experimental Approach to the Internal/External Frame of Reference Model.
ERIC Educational Resources Information Center
Moller, Jens; Koller, Olaf
2001-01-01
Three experimental studies investigated psychological processes underlying the effects of achievement in one domain and on self-perceived competence in another. In Study 1, high achievement in one domain led to lower self-perceived competence in the other. Study 2 showed inverse effects on self-perceived competence based on achievement feedback.…
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…
ERIC Educational Resources Information Center
Ercan, Orhan; Bilen, Kadir; Ural, Evrim
2016-01-01
This study investigated the impact of a web-based teaching method on students' academic achievement and attitudes in the elementary education fifth grade Science and Technology unit, "System of Earth, Sun and Moon". The study was a quasi-experimental study with experimental and control groups comprising 54 fifth grade students attending…
Quasi-experimental study designs series-paper 9: collecting data from quasi-experimental studies.
Aloe, Ariel M; Becker, Betsy Jane; Duvendack, Maren; Valentine, Jeffrey C; Shemilt, Ian; Waddington, Hugh
2017-09-01
To identify variables that must be coded when synthesizing primary studies that use quasi-experimental designs. All quasi-experimental (QE) designs. When designing a systematic review of QE studies, potential sources of heterogeneity-both theory-based and methodological-must be identified. We outline key components of inclusion criteria for syntheses of quasi-experimental studies. We provide recommendations for coding content-relevant and methodological variables and outlined the distinction between bivariate effect sizes and partial (i.e., adjusted) effect sizes. Designs used and controls used are viewed as of greatest importance. Potential sources of bias and confounding are also addressed. Careful consideration must be given to inclusion criteria and the coding of theoretical and methodological variables during the design phase of a synthesis of quasi-experimental studies. The success of the meta-regression analysis relies on the data available to the meta-analyst. Omission of critical moderator variables (i.e., effect modifiers) will undermine the conclusions of a meta-analysis. Copyright © 2017 Elsevier Inc. All rights reserved.
ERIC Educational Resources Information Center
Halupa, Colleen M.; Caldwell, Benjamin W.
2015-01-01
This quasi-experimental research study evaluated two intact undergraduate engineering statics classes at a private university in Texas. Students in the control group received traditional lecture, readings and homework assignments. Those in the experimental group also were given access to a complete set of online video lectures and videos…
ERIC Educational Resources Information Center
Al Sadi, Fatma H.; Basit, Tehmina N.
2017-01-01
This paper is based on a quasi-experimental study which examines the effects of a school-based intervention on Omani girls' attitudes towards the notion of gender equality. A questionnaire was administered before and after the intervention to 241 girls (116 in the experimental group; 125 in the control group). A semi-structured interview was…
Games for Traffic Education: An Experimental Study of a Game-Based Driving Simulator
ERIC Educational Resources Information Center
Backlund, Per; Engstrom, Henrik; Johannesson, Mikael; Lebram, Mikael
2010-01-01
In this article, the authors report on the construction and evaluation of a game-based driving simulator using a real car as a joystick. The simulator is constructed from off-the-shelf hardware and the simulation runs on open-source software. The feasibility of the simulator as a learning tool has been experimentally evaluated. Results are…
An Increasing of Primary School Teachers' Competency in Brain-Based Learning
ERIC Educational Resources Information Center
Waree, Chaiwat
2017-01-01
The purpose of the study was to develop a powerful and empowering guide (CBT) of elementary school teachers, to compare the ability of elementary school teachers. Management learning uses brain as a base. The experimental group with a control group the experimental group used in this research was a teacher at the grade level. 4-6 in province By…
Oh, Hyun Soo; Park, Won; Kwon, Seong Ryul; Lim, Mie Jin; Suh, Yeon Ok; Seo, Wha Sook; Park, Jong Suk
2013-08-01
This study was conducted to examine the changing patterns of knowledge related to disease, medication adherence, and self-management and to determine if outcomes were more favorable in the experimental group than in the comparison group through 6 months after providing a web-based self-management intervention. A non-equivalent control group quasi-experimental design was used and 65 patients with gout, 34 in experimental group and 31 in comparison group, were selected from the rheumatic clinics of two university hospitals. Data were collected four times, at baseline, at 1 month, 3 months, and 6 months after the intervention. According to the study results, the changing patterns of knowledge and self-management were more positive in the experimental group than in the control group, whereas difference in the changing pattern of medication adherence between two groups was not significant. The results indicate that the web-based self-management program has significant effect on improving knowledge and self-management for middle aged male patients with gout. However, in order to enhance medication adherence, the web-based intervention might not be sufficient and other strategies need to be added.
Data base for the prediction of inlet external drag
NASA Technical Reports Server (NTRS)
Mcmillan, O. J.; Perkins, E. W.; Perkins, S. C., Jr.
1980-01-01
Results are presented from a study to define and evaluate the data base for predicting an airframe/propulsion system interference effect shown to be of considerable importance, inlet external drag. The study is focused on supersonic tactical aircraft with highly integrated jet propulsion systems, although some information is included for supersonic strategic aircraft and for transport aircraft designed for high subsonic or low supersonic cruise. The data base for inlet external drag is considered to consist of the theoretical and empirical prediction methods as well as the experimental data identified in an extensive literature search. The state of the art in the subsonic and transonic speed regimes is evaluated. The experimental data base is organized and presented in a series of tables in which the test article, the quantities measured and the ranges of test conditions covered are described for each set of data; in this way, the breadth of coverage and gaps in the existing experimental data are evident. Prediction methods are categorized by method of solution, type of inlet and speed range to which they apply, major features are given, and their accuracy is assessed by means of comparison to experimental data.
Experimental study of low-cost fiber optic distributed temperature sensor system performance
NASA Astrophysics Data System (ADS)
Dashkov, Michael V.; Zharkov, Alexander D.
2016-03-01
The distributed control of temperature is an actual task for various application such as oil & gas fields, high-voltage power lines, fire alarm systems etc. The most perspective are optical fiber distributed temperature sensors (DTS). They have advantages on accuracy, resolution and range, but have a high cost. Nevertheless, for some application the accuracy of measurement and localization aren't so important as cost. The results of an experimental study of low-cost Raman based DTS based on standard OTDR are represented.
[Effect of school-based peer leader centered smoking prevention program].
Shin, Sung Rae; Oh, Pok Ja; Youn, Hye Kyung; Shin, Sun Hwa
2014-12-01
The purpose of this study was to develop and evaluate a school-based peer leader centered smoking prevention program. Non-equivalent control group with a pre/post-test design was used. Students (n=174) in two boys' junior high schools located in D city, Korea participated with 85 being selected for the experimental group and 89 for the control group. Five sessions were given to the experimental group and a 50 minute lecture to the control group. Knowledge, attitude, non-smoking intention, and non-smoking efficacy were measured for the both experimental and control group at two weeks before the program and one month after the program was completed. Data were analyzed using χ²-test, Fisher's exact test, independent t-test and paired t-test with the SPSS 21.0 program. The experimental group showed higher overall knowledge, negative attitude toward smoking, and higher non-smoking intention and efficacy. After receiving the school based peer leader centered smoking prevention program scores for attitude toward smoking and non-smoking efficacy increased in the experimental group were higher than in the control group. The school-based peer leader centered smoking prevention program needs longitudinal evaluation, but from this study, there is an indication that this program can be used with junior high school students and effectively change students' attitude toward smoking and promote non-smoking efficacy.
Kwon, Hye Kyung; Lee, Sook Ja
2017-06-01
The aim of this study was to develop and measure the effect of a movie-based-nursing intervention program designed to enhance motivation for rehabilitation and reduce depression levels in stroke patients. The study used a quasi-experimental, nonequivalent control group and a pretest-posttest design. The 60 research subjects were assigned to the experimental (n=30) or control group (n=30). The moviebased nursing intervention program was provided for the experimental group during 60-minute sessions held once per week for 10 weeks. The program consisted of patient education to strengthen motivation for rehabilitation and reduce depression, watching movies to identify role models, and group discussion to facilitate therapeutic interaction. After 10 weeks of participation in the movie-based nursing intervention program, the experimental group's rehabilitation motivation score was significantly higher, F=1161.54 (within groups df=49, between groups df=1), p<.001, relative to that observed in the control group. In addition, the experimental group's depression score was significantly lower relative to that observed in the control group, F=258.97 (within groups df=49, between groups df=1), p<.001. The movie-based nursing intervention program could be used for stroke patients experiencing psychological difficulties including reduced motivation for rehabilitation and increased depression during the rehabilitation process. © 2017 Korean Society of Nursing Science
Kunstler, Breanne E; Cook, Jill L; Freene, Nicole; Finch, Caroline F; Kemp, Joanne L; O'Halloran, Paul D; Gaida, James E
2018-06-01
Physiotherapists promote physical activity as part of their practice. This study reviewed the behaviour change techniques physiotherapists use when promoting physical activity in experimental and observational studies. Systematic review of experimental and observational studies. Twelve databases were searched using terms related to physiotherapy and physical activity. We included experimental studies evaluating the efficacy of physiotherapist-led physical activity interventions delivered to adults in clinic-based private practice and outpatient settings to individuals with, or at risk of, non-communicable diseases. Observational studies reporting the techniques physiotherapists use when promoting physical activity were also included. The behaviour change techniques used in all studies were identified using the Behaviour Change Technique Taxonomy. The behaviour change techniques appearing in efficacious and inefficacious experimental interventions were compared using a narrative approach. Twelve studies (nine experimental and three observational) were retained from the initial search yield of 4141. Risk of bias ranged from low to high. Physiotherapists used seven behaviour change techniques in the observational studies, compared to 30 behaviour change techniques in the experimental studies. Social support (unspecified) was the most frequently identified behaviour change technique across both settings. Efficacious experimental interventions used more behaviour change techniques (n=29) and functioned in more ways (n=6) than did inefficacious experimental interventions (behaviour change techniques=10 and functions=1). Physiotherapists use a small number of behaviour change techniques. Less behaviour change techniques were identified in observational studies compared to experimental studies, suggesting physiotherapists use less BCTs clinically than experimentally. Copyright © 2017 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.
Saas, Philippe; Daguindau, Etienne; Perruche, Sylvain
2016-06-01
The objectives of this review are to summarize the experimental data obtained using apoptotic cell-based therapies, and then to discuss future clinical developments. Indeed, apoptotic cells exhibit immunomodulatory properties that are reviewed here by focusing on more recent mechanisms. These immunomodulatory mechanisms are in particular linked to the clearance of apoptotic cells (called also efferocytosis) by phagocytes, such as macrophages, and the induction of regulatory T cells. Thus, apoptotic cell-based therapies have been used to prevent or treat experimental inflammatory diseases. Based on these studies, we have identified critical steps to design future clinical trials. This includes: the administration route, the number and schedule of administration, the appropriate apoptotic cell type to be used, as well as the apoptotic signal. We also have analyzed the clinical relevancy of apoptotic-cell-based therapies in experimental models. Additional experimental data are required concerning the treatment of inflammatory diseases (excepted for sepsis) before considering future clinical trials. In contrast, apoptotic cells have been shown to favor engraftment and to reduce acute graft-versus-host disease (GvHD) in different relevant models of transplantation. This has led to the conduct of a phase 1/2a clinical trial to alleviate GvHD. The absence of toxic effects obtained in this trial may support the development of other clinical studies based on this new cell therapy. Stem Cells 2016;34:1464-1473. © 2016 AlphaMed Press.
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.
Adhesive joint evaluation by ultrasonic interface and lamb waves
NASA Technical Reports Server (NTRS)
Rokhlin, S. I.
1986-01-01
Some results on the application of interface and Lamb waves for the study of curing of thin adhesive layers were summarized. In the case of thick substrates (thickness much more than the wave length) the interface waves can be used. In this case the experimental data can be inverted and the shear modulus of the adhesive film may be explicitly found based on the measured interface wave velocity. It is shown that interface waves can be used for the study of curing of structural adhesives as a function of different temperatures and other experimental conditions. The kinetics of curing was studied. In the case of thin substrates the wave phenomena are much more complicated. It is shown that for successful measurements proper selection of experimental conditions is very important. This can be done based on theoretical estimations. For correctly selected experimental conditions the Lamb waves may be a sensitive probe of adhesive bond quality and may be used or cure monitoring.
A school-based health promotion program for stressed nursing students in Taiwan.
Hsieh, Pei-Lin
2011-09-01
: Nursing students face both clinical and academic stress. Extensive theoretical and research literature suggests that peer support and regular exercise are critically important and can efficiently manage stress for nursing students. : The purpose of this study was to investigate the effect of a school-based health promotion program in a group physical activity intervention and peer support program for stressed nursing students. : This study used a quasi-experimental design to collect information and collected data from a stress questionnaire, semistructured questionnaire, and group discussion. Participants included 77 nursing students at an institute of technology in northern Taiwan. Participants were randomly assigned into experimental (n = 37) and control (n = 40) groups. Program duration was 16 weeks. Participants were selected based on their assessment results as having moderate or severe levels of stress. All participants in the experimental group took part in a group physical activity for 30 minutes three times a week. Eight weeks later, the researcher invited each group to discuss their feelings and stress coping strategies. Both groups completed pretest and posttest stress questionnaires. Quantitative data were analyzed using SPSS 14.0 Statistical Package for Windows, and qualitative data from each group discussion were analyzed using content analysis. : Results revealed that level of stress was statistically decreased in the experimental group. Posttest stress levels were significantly different in experimental and control groups. The results suggested that students who participated in the intervention had less stress than did those in the control group after the intervention. Those in the experimental group held positive views of peer support and physical activity. : The results of this study confirmed the efficacy of school-based health promotion programs in reducing stress in nursing students. Findings may provide educators with information to assist their developing effective health promotion programs to manage stress for their students. This study can also help students develop personal coping strategies through physical activity and peer support.
Modelling of Batch Lactic Acid Fermentation in the Presence of Anionic Clay
Jinescu, Cosmin; Aruş, Vasilica Alisa; Nistor, Ileana Denisa
2014-01-01
Summary Batch fermentation of milk inoculated with lactic acid bacteria was conducted in the presence of hydrotalcite-type anionic clay under static and ultrasonic conditions. An experimental study of the effect of fermentation temperature (t=38–43 °C), clay/milk ratio (R=1–7.5 g/L) and ultrasonic field (ν=0 and 35 kHz) on process dynamics was performed. A mathematical model was selected to describe the fermentation process kinetics and its parameters were estimated based on experimental data. A good agreement between the experimental and simulated results was achieved. Consequently, the model can be employed to predict the dynamics of batch lactic acid fermentation with values of process variables in the studied ranges. A statistical analysis of the data based on a 23 factorial experiment was performed in order to express experimental and model-regressed process responses depending on t, R and ν factors. PMID:27904318
NASA Astrophysics Data System (ADS)
Cheng, Yongzhi; Nie, Yan; Wang, Xian; Gong, Rongzhou
2014-02-01
In this paper, the magnetic rubber plate absorber (MRPA) and metamaterial absorber (MA) based on MRP substrate were proposed and studied numerically and experimentally. Based on the characteristic of L-C resonances, experimental results show that the MA composed of cross resonator (CR) embedded single layer MRP could be adjustable easily by changing the wire length and width of CR structure and MRP thickness. Finally, experimental results show that the MA composed of CR-embedded two layers MRP with the total thickness of 2.42 mm exhibit a -10 dB absorption bandwidth from 1.65 GHz to 3.7 GHz, which is 1.86 times wider than the same thickness MRPA.
Lee, Jung Min; Kim, Shin-Jeong; Min, Hae Young
This study aimed to identify the effects of smartphone-based nebulizer therapy education on the knowledge and confidence of parents while performing care for their children with respiratory disease. This quasi-experimental study employed a pretest-posttest design using a nonequivalent control group. Data were collected from children's parents who had not used nebulizer therapy for their children previously. Both the groups were given nebulizer therapy education using the same content but different learning methods. The experimental group (n=36) was taught using smartphones, while the control group (n=36) was taught using verbal and paper-based methods. The data were analyzed using the Chi Square test, repeated measures analysis of variance, and t-test. The mean scores on knowledge improvement (F=100.949, p<0.001) and confidence in performing care (t=-6.959, p<0.001) were significantly higher for the experimental group as compared to the control group. Further, the scores on satisfaction with the learning method were significantly higher for the experimental group as compared to the control group (t=-5.819, p<0.001). Our results suggest that smartphone-based education on nebulizer therapy might be effective in improving parents' knowledge and confidence in performing care for their children. This study suggests that smartphone-based education needs to be considered as an effective educational intervention in providing nursing support for parents of children with respiratory disease. Copyright © 2017 Elsevier Inc. All rights reserved.
Cooke, Steven J; Birnie-Gauvin, Kim; Lennox, Robert J; Taylor, Jessica J; Rytwinski, Trina; Rummer, Jodie L; Franklin, Craig E; Bennett, Joseph R; Haddaway, Neal R
2017-01-01
Policy development and management decisions should be based upon the best available evidence. In recent years, approaches to evidence synthesis, originating in the medical realm (such as systematic reviews), have been applied to conservation to promote evidence-based conservation and environmental management. Systematic reviews involve a critical appraisal of evidence, but studies that lack the necessary rigour (e.g. experimental, technical and analytical aspects) to justify their conclusions are typically excluded from systematic reviews or down-weighted in terms of their influence. One of the strengths of conservation physiology is the reliance on experimental approaches that help to more clearly establish cause-and-effect relationships. Indeed, experimental biology and ecology have much to offer in terms of building the evidence base that is needed to inform policy and management options related to pressing issues such as enacting endangered species recovery plans or evaluating the effectiveness of conservation interventions. Here, we identify a number of pitfalls that can prevent experimental findings from being relevant to conservation or would lead to their exclusion or down-weighting during critical appraisal in a systematic review. We conclude that conservation physiology is well positioned to support evidence-based conservation, provided that experimental designs are robust and that conservation physiologists understand the nuances associated with informing decision-making processes so that they can be more relevant.
Birnie-Gauvin, Kim; Lennox, Robert J.; Taylor, Jessica J.; Rytwinski, Trina; Rummer, Jodie L.; Franklin, Craig E.; Bennett, Joseph R.; Haddaway, Neal R.
2017-01-01
Abstract Policy development and management decisions should be based upon the best available evidence. In recent years, approaches to evidence synthesis, originating in the medical realm (such as systematic reviews), have been applied to conservation to promote evidence-based conservation and environmental management. Systematic reviews involve a critical appraisal of evidence, but studies that lack the necessary rigour (e.g. experimental, technical and analytical aspects) to justify their conclusions are typically excluded from systematic reviews or down-weighted in terms of their influence. One of the strengths of conservation physiology is the reliance on experimental approaches that help to more clearly establish cause-and-effect relationships. Indeed, experimental biology and ecology have much to offer in terms of building the evidence base that is needed to inform policy and management options related to pressing issues such as enacting endangered species recovery plans or evaluating the effectiveness of conservation interventions. Here, we identify a number of pitfalls that can prevent experimental findings from being relevant to conservation or would lead to their exclusion or down-weighting during critical appraisal in a systematic review. We conclude that conservation physiology is well positioned to support evidence-based conservation, provided that experimental designs are robust and that conservation physiologists understand the nuances associated with informing decision-making processes so that they can be more relevant. PMID:28835842
Systematic methods for the design of a class of fuzzy logic controllers
NASA Astrophysics Data System (ADS)
Yasin, Saad Yaser
2002-09-01
Fuzzy logic control, a relatively new branch of control, can be used effectively whenever conventional control techniques become inapplicable or impractical. Various attempts have been made to create a generalized fuzzy control system and to formulate an analytically based fuzzy control law. In this study, two methods, the left and right parameterization method and the normalized spline-base membership function method, were utilized for formulating analytical fuzzy control laws in important practical control applications. The first model was used to design an idle speed controller, while the second was used to control an inverted control problem. The results of both showed that a fuzzy logic control system based on the developed models could be used effectively to control highly nonlinear and complex systems. This study also investigated the application of fuzzy control in areas not fully utilizing fuzzy logic control. Three important practical applications pertaining to the automotive industries were studied. The first automotive-related application was the idle speed of spark ignition engines, using two fuzzy control methods: (1) left and right parameterization, and (2) fuzzy clustering techniques and experimental data. The simulation and experimental results showed that a conventional controller-like performance fuzzy controller could be designed based only on experimental data and intuitive knowledge of the system. In the second application, the automotive cruise control problem, a fuzzy control model was developed using parameters adaptive Proportional plus Integral plus Derivative (PID)-type fuzzy logic controller. Results were comparable to those using linearized conventional PID and linear quadratic regulator (LQR) controllers and, in certain cases and conditions, the developed controller outperformed the conventional PID and LQR controllers. The third application involved the air/fuel ratio control problem, using fuzzy clustering techniques, experimental data, and a conversion algorithm, to develop a fuzzy-based control algorithm. Results were similar to those obtained by recently published conventional control based studies. The influence of the fuzzy inference operators and parameters on performance and stability of the fuzzy logic controller was studied Results indicated that, the selections of certain parameters or combinations of parameters, affect greatly the performance and stability of the fuzzy controller. Diagnostic guidelines used to tune or change certain factors or parameters to improve controller performance were developed based on knowledge gained from conventional control methods and knowledge gained from the experimental and the simulation results of this study.
Promoting students' conceptual understanding using STEM-based e-book
NASA Astrophysics Data System (ADS)
Komarudin, U.; Rustaman, N. Y.; Hasanah, L.
2017-05-01
This study aims to examine the effect of Science, Technology, Engineering, and Mathematics (STEM) based e-book in promoting students'conceptual understanding on lever system in human body. The E-book used was the e-book published by National Ministry of Science Education. The research was conducted by a quasi experimental with pretest and posttest design. The subjects consist of two classes of 8th grade junior high school in Pangkalpinang, Indonesia, which were devided into experimental group (n=34) and control group (n=32). The students in experimental group was taught by STEM-based e-book, while the control group learned by non STEM-based e-book. The data was collected by an instrument pretest and postest. Pretest and posttest scored, thenanalyzed using descriptive statistics and independent t-test. The result of independent sample t-test shows that no significant differenceson students' pretest score between control and experimental group. However, there were significant differences on students posttest score and N-gain score between control and experimental group with sig = 0.000(p<0.005). N-gain analysis showsthe higher performance of students who were participated in experimental group (mean = 66.03) higher compared to control group (mean = 47.66) in answering conceptual understanding questions. Based on the results, it can be concluded that STEM-based e-book has positiveimpact in promoting students' understanding on lever system in human body. Therefore this learning approach is potential to be used as an alternative to triger the enhancement of students' understanding in science.
3-D and quasi-2-D discrete element modeling of grain commingling in a bucket elevator boot system
USDA-ARS?s Scientific Manuscript database
Unwanted grain commingling impedes new quality-based grain handling systems and has proven to be an expensive and time consuming issue to study experimentally. Experimentally validated models may reduce the time and expense of studying grain commingling while providing additional insight into detail...
ERIC Educational Resources Information Center
Kim, Heesung; Ke, Fengfeng
2017-01-01
This experimental study was intended to examine whether the integration of game characteristics in the OpenSimulator-supported virtual reality (VR) learning environment can improve mathematical achievement for elementary school students. In this pre- and posttest experimental comparison study, data were collected from 132 fourth graders through an…
Using entropy measures to characterize human locomotion.
Leverick, Graham; Szturm, Tony; Wu, Christine Q
2014-12-01
Entropy measures have been widely used to quantify the complexity of theoretical and experimental dynamical systems. In this paper, the value of using entropy measures to characterize human locomotion is demonstrated based on their construct validity, predictive validity in a simple model of human walking and convergent validity in an experimental study. Results show that four of the five considered entropy measures increase meaningfully with the increased probability of falling in a simple passive bipedal walker model. The same four entropy measures also experienced statistically significant increases in response to increasing age and gait impairment caused by cognitive interference in an experimental study. Of the considered entropy measures, the proposed quantized dynamical entropy (QDE) and quantization-based approximation of sample entropy (QASE) offered the best combination of sensitivity to changes in gait dynamics and computational efficiency. Based on these results, entropy appears to be a viable candidate for assessing the stability of human locomotion.
A comparison of problem-based learning and conventional teaching in nursing ethics education.
Lin, Chiou-Fen; Lu, Meei-Shiow; Chung, Chun-Chih; Yang, Che-Ming
2010-05-01
The aim of this study was to compare the learning effectiveness of peer tutored problem-based learning and conventional teaching of nursing ethics in Taiwan. The study adopted an experimental design. The peer tutored problem-based learning method was applied to an experimental group and the conventional teaching method to a control group. The study sample consisted of 142 senior nursing students who were randomly assigned to the two groups. All the students were tested for their nursing ethical discrimination ability both before and after the educational intervention. A learning satisfaction survey was also administered to both groups at the end of each course. After the intervention, both groups showed a significant increase in ethical discrimination ability. There was a statistically significant difference between the ethical discrimination scores of the two groups (P < 0.05), with the experimental group on average scoring higher than the control group. There were significant differences in satisfaction with self-motivated learning and critical thinking between the groups. Peer tutored problem-based learning and lecture-type conventional teaching were both effective for nursing ethics education, but problem-based learning was shown to be more effective. Peer tutored problem-based learning has the potential to enhance the efficacy of teaching nursing ethics in situations in which there are personnel and resource constraints.
The Effect of Progressive Sentence Development Activities on 5th Graders' Description Skills
ERIC Educational Resources Information Center
Hamzadayi, Ergun
2015-01-01
The aim of this study was to examine the effect of progressive sentence development activities on 5th graders' description skills. The study was conducted based on the pretest-posttest quasi-experimental model with a control group. A total of 58 students participated in the study; 29 in the control group, and 29 in the experimental group. The…
ERIC Educational Resources Information Center
Armah, Robert Benjamin; Cofie, Primrose Otokonor; Okpoti, Christopher Adjei
2018-01-01
This study investigated the effect of van Hiele Phase-based Instruction (VHPI) on Ghanaian Pre-service Teachers' (PTs') geometric thinking in terms of the van Hiele Levels. A pre-test post-test quasi-experimental design was employed. There were 75 PTs each in the experimental group and the control group. Van Hiele Geometry Test (VHGT) was…
ERIC Educational Resources Information Center
González-Cutre, David; Sierra, Ana C.; Beltrán-Carrillo, Vicente J.; Peláez-Pérez, Manuel; Cervelló, Eduardo
2018-01-01
The authors analyzed the effects of a multidimensional intervention to promote physical activity (PA) in school, based on self-determination theory. The study involved 88 students, between 14 and 17 years old, who were divided into a control group (n = 59) and an experimental group (n = 29). In the experimental group, a 6-month intervention was…
ERIC Educational Resources Information Center
Colakkadioglu, Oguzhan; Gucray, S. Sonay
2012-01-01
In this study, the effect of conflict theory based decision making skill training group applications on decision making styles of adolescents was investigated. A total of 36 students, including 18 students in experimental group and 18 students in control group, participated in the research. When assigning students to experimental group or control…
Wyman C. Schmidt; Judy L. Friede
1996-01-01
This is a compendium of experimental forests, ranges, watersheds, and other outdoor laboratories, formally established by the Forest Service and Agricultural Research Service of the U.S. Department of Agriculture, and the universities in Utah, Idaho, and Montana. The purposes, histories, natural resource bases, data bases, past and current studies, locations, and who...
NASA Technical Reports Server (NTRS)
Alcorn, Charles W.; Britcher, Colin
1988-01-01
An experimental investigation is reported on slanted base ogive cylinders at zero incidence. The Mach number range is 0.05 to 0.3. All flow disturbances associated with wind tunnel supports are eliminated in this investigation by magnetically suspending the wind tunnel models. The sudden and drastic changes in the lift, pitching moment, and drag for a slight change in base slant angle are reported. Flow visualization with liquid crystals and oil is used to observe base flow patterns, which are responsible for the sudden changes in aerodynamic characteristics. Hysteretic effects in base flow pattern changes are present in this investigation and are reported. The effect of a wire support attachment on the 0 deg slanted base model is studied. Computational drag and transition location results using VSAERO and SANDRAG are presented and compared with experimental results. Base pressure measurements over the slanted bases are made with an onboard pressure transducer using remote data telemetry.
NASA Astrophysics Data System (ADS)
Liliawati, W.; Purwanto; Zulfikar, A.; Kamal, R. N.
2018-05-01
This study aims to examine the effectiveness of the use of teaching materials based on multiple intelligences on the understanding of high school students’ material on the theme of global warming. The research method used is static-group pretest-posttest design. Participants of the study were 60 high school students of XI class in one of the high schools in Bandung. Participants were divided into two classes of 30 students each for the experimental class and control class. The experimental class uses compound-based teaching materials while the experimental class does not use a compound intelligence-based teaching material. The instrument used is a test of understanding of the concept of global warming with multiple choices form amounted to 15 questions and 5 essay items. The test is given before and after it is applied to both classes. Data analysis using N-gain and effect size. The results obtained that the N-gain for both classes is in the medium category and the effectiveness of the use of teaching materials based on the results of effect-size test results obtained in the high category.
[Bases and methods of suturing].
Vogt, P M; Altintas, M A; Radtke, C; Meyer-Marcotty, M
2009-05-01
If pharmaceutic modulation of scar formation does not improve the quality of the healing process over conventional healing, the surgeon must rely on personal skill and experience. Therefore a profound knowledge of wound healing based on experimental and clinical studies supplemented by postsurgical means of scar management and basic techniques of planning incisions, careful tissue handling, and thorough knowledge of suturing remain the most important ways to avoid abnormal scarring. This review summarizes the current experimental and clinical bases of surgical scar management.
Electrical coupled Morris-Lecar neurons: From design to pattern analysis
DOE Office of Scientific and Technical Information (OSTI.GOV)
Binczak, S.; Behdad, R.; Rossé, M.
2016-06-08
In this study, an experimental electronic neuron based on Morris-Lecar model is presented, able to become an experimental unit tool to study collective association of robust coupled neurons. The circuit design is given according to the ionic currents of this model. A weak coupling of such neurons under Multisim Software can generate clusters based on the boundary conditions of the neurons and their initial conditions. For this study, we work in the region close to the fold bifurcation of limit cycles. In this region two limit cycles exist, one of the cycles is stable and another one is unstable.
Study on light scattering characterization for polishing surface of optical elements
NASA Astrophysics Data System (ADS)
Zhang, Yingge; Tian, Ailing; Wang, Chunhui; Wang, Dasen; Liu, Weiguo
2017-02-01
Based on the principle of bidirectional reflectance distribution function (BRDF), the relationship between the surface roughness and the spatial scattering distribution of the optical elements were studied. First, a series of optical components with different surface roughness was obtained by the traditional polishing processing, and measured by Talysurf CCI 3000. Secondly, the influences of different factors on the scattering characteristics were simulated and analyzed, such as different surface roughness, incident wavelength and incident angle. Finally, the experimental device was built, and the spatial distribution of scattered light was measured with the different conditions, and then the data curve variation was analyzed. It was shown that the experimental method was reliable by comparing the simulation and experimental results. Base on this to know, many studies on light scattering characteristics for optical element polishing surface can try later.
Milani, Atefeh; Nikmanesh, Zahra; Farnam, Ali
2013-12-01
In the present era, delinquency in children and adolescents is undoubtedly a difficult and upsetting issue attracting the attention of many experts such as psychologists, sociologists, and criminologists. These experts often try to answer why a number of children and adolescents engage in various crimes such as aggressive and anti-social crimes. They also try to find out how these crimes can be prevented. The present study investigates the effectiveness of mindfulness-based cognitive therapy training (MBCT) in reducing aggression in a juvenile correction and rehabilitation center of Zahedan province during years 1991 to 1992. This experimental study included an experimental and a control group with a pretest, posttest, and follow-up approach. The Buss and Perry aggression questionnaire (1992) was used for data collection. The sample group included 22 (10 experimental and 12 control groups) adolescent males in a juvenile correction and rehabilitation center of Zahedan province who were selected through a census method. Using a matching method based on the pre-test scores of the aggression questionnaire, they were then divided into two equivalent categories and were randomly assigned to the two groups. Mindfulness-based cognitive training took the group training in 8 sessions administered on experimental group. The follow-up test was conducted two weeks after the end of the posttest sessions. The results were analyzed using ANCOVA. The results of ANCOVA showed that mindfulness-based cognitive training could significantly reduce aggression during posttest and follow-up test phases in the experimental group, compared to the control group (P < 0.01). Moreover, the results indicated the effectiveness of this method in significantly reducing anger, physical aggression, and hostility during posttest and follow-up test phases (P < 0.05). However, no significant reduction was observed in the verbal aggression subscale. According to the results of the present study, mindfulness-based cognitive training seems to be effective for reducing aggressive behaviors.
NASA Astrophysics Data System (ADS)
Tahernezhad-Javazm, Farajollah; Azimirad, Vahid; Shoaran, Maryam
2018-04-01
Objective. Considering the importance and the near-future development of noninvasive brain-machine interface (BMI) systems, this paper presents a comprehensive theoretical-experimental survey on the classification and evolutionary methods for BMI-based systems in which EEG signals are used. Approach. The paper is divided into two main parts. In the first part, a wide range of different types of the base and combinatorial classifiers including boosting and bagging classifiers and evolutionary algorithms are reviewed and investigated. In the second part, these classifiers and evolutionary algorithms are assessed and compared based on two types of relatively widely used BMI systems, sensory motor rhythm-BMI and event-related potentials-BMI. Moreover, in the second part, some of the improved evolutionary algorithms as well as bi-objective algorithms are experimentally assessed and compared. Main results. In this study two databases are used, and cross-validation accuracy (CVA) and stability to data volume (SDV) are considered as the evaluation criteria for the classifiers. According to the experimental results on both databases, regarding the base classifiers, linear discriminant analysis and support vector machines with respect to CVA evaluation metric, and naive Bayes with respect to SDV demonstrated the best performances. Among the combinatorial classifiers, four classifiers, Bagg-DT (bagging decision tree), LogitBoost, and GentleBoost with respect to CVA, and Bagging-LR (bagging logistic regression) and AdaBoost (adaptive boosting) with respect to SDV had the best performances. Finally, regarding the evolutionary algorithms, single-objective invasive weed optimization (IWO) and bi-objective nondominated sorting IWO algorithms demonstrated the best performances. Significance. We present a general survey on the base and the combinatorial classification methods for EEG signals (sensory motor rhythm and event-related potentials) as well as their optimization methods through the evolutionary algorithms. In addition, experimental and statistical significance tests are carried out to study the applicability and effectiveness of the reviewed methods.
Mohsenizadeh, Daniel N; Dehghannasiri, Roozbeh; Dougherty, Edward R
2018-01-01
In systems biology, network models are often used to study interactions among cellular components, a salient aim being to develop drugs and therapeutic mechanisms to change the dynamical behavior of the network to avoid undesirable phenotypes. Owing to limited knowledge, model uncertainty is commonplace and network dynamics can be updated in different ways, thereby giving multiple dynamic trajectories, that is, dynamics uncertainty. In this manuscript, we propose an experimental design method that can effectively reduce the dynamics uncertainty and improve performance in an interaction-based network. Both dynamics uncertainty and experimental error are quantified with respect to the modeling objective, herein, therapeutic intervention. The aim of experimental design is to select among a set of candidate experiments the experiment whose outcome, when applied to the network model, maximally reduces the dynamics uncertainty pertinent to the intervention objective.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chen, S.S.; Zhu, S.; Cai, Y.
Motion-dependent magnetic forces are the key elements in the study of magnetically levitated vehicle (maglev) system dynamics. In the past, most maglev-system designs were based on a quasisteady-motion theory of magnetic forces. This report presents an experimental and analytical study that will enhance our understanding of the role of unsteady-motion-dependent magnetic forces and demonstrate an experimental technique that can be used to measure those unsteady magnetic forces directly. The experimental technique provides a useful tool to measure motion-dependent magnetic forces for the prediction and control of maglev systems.
Providing Guidance in Virtual Lab Experimentation: The Case of an Experiment Design Tool
ERIC Educational Resources Information Center
Efstathiou, Charalampos; Hovardas, Tasos; Xenofontos, Nikoletta A.; Zacharia, Zacharias C.; deJong, Ton; Anjewierden, Anjo; van Riesen, Siswa A. N.
2018-01-01
The present study employed a quasi-experimental design to assess a computer-based tool, which was intended to scaffold the task of designing experiments when using a virtual lab for the process of experimentation. In particular, we assessed the impact of this tool on primary school students' cognitive processes and inquiry skills before and after…
A Benchmark and Comparative Study of Video-Based Face Recognition on COX Face Database.
Huang, Zhiwu; Shan, Shiguang; Wang, Ruiping; Zhang, Haihong; Lao, Shihong; Kuerban, Alifu; Chen, Xilin
2015-12-01
Face recognition with still face images has been widely studied, while the research on video-based face recognition is inadequate relatively, especially in terms of benchmark datasets and comparisons. Real-world video-based face recognition applications require techniques for three distinct scenarios: 1) Videoto-Still (V2S); 2) Still-to-Video (S2V); and 3) Video-to-Video (V2V), respectively, taking video or still image as query or target. To the best of our knowledge, few datasets and evaluation protocols have benchmarked for all the three scenarios. In order to facilitate the study of this specific topic, this paper contributes a benchmarking and comparative study based on a newly collected still/video face database, named COX(1) Face DB. Specifically, we make three contributions. First, we collect and release a largescale still/video face database to simulate video surveillance with three different video-based face recognition scenarios (i.e., V2S, S2V, and V2V). Second, for benchmarking the three scenarios designed on our database, we review and experimentally compare a number of existing set-based methods. Third, we further propose a novel Point-to-Set Correlation Learning (PSCL) method, and experimentally show that it can be used as a promising baseline method for V2S/S2V face recognition on COX Face DB. Extensive experimental results clearly demonstrate that video-based face recognition needs more efforts, and our COX Face DB is a good benchmark database for evaluation.
Charge of the containerless experimentation in microgravity
NASA Technical Reports Server (NTRS)
Lee, Mark C.
1990-01-01
The experimentation was undertaken to study the elimination or reduction of surface contamination for which there is adequate Earth-based technology along with the reduction of dynamic nucleation for which there a paucity of reliable data. One objective is to delineate scientific justification of the U.S. Containerless Experimentation Program in Microgravity for the next decade and beyond. Another objective is for the guidance of NASA to define the next generation of containerless experimentation instruments in microgravity.
Quasi experimental designs in pharmacist intervention research.
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.
The Contribution of Music to the Fluent Writing Skills: Mayaz Technique
ERIC Educational Resources Information Center
Batur, Zekerya
2016-01-01
This is an experimental study. In this study, experimental and control groups have been formed based on the scores obtained from Turkish language exams. The study group consists of 80 pupils currently studying in the 5th and 6th grades of the secondary school who have an average GPA of 70 to 80 (of the 5th grade pupils, 20 of them are in the…
ERIC Educational Resources Information Center
Hirsch, Jorge E.; Scalapino, Douglas J.
1983-01-01
Discusses ways computers are being used in condensed-matter physics by experimenters and theorists. Experimenters use them to control experiments and to gather and analyze data. Theorists use them for detailed predictions based on realistic models and for studies on systems not realizable in practice. (JN)
Laser-ion accelerators: State-of-the-art and scaling laws
DOE Office of Scientific and Technical Information (OSTI.GOV)
Borghesi, M.; Kar, S.; Margarone, D.
2013-07-26
A significant amount of experimental work has been devoted over the last decade to the development and optimization of proton acceleration based on the so-called Target Normal Sheath acceleration mechanism. Several studies have been dedicated to the determination of scaling laws for the maximum energy of the protons as a function of the parameters of the irradiating pulses, studies based on experimental results and on models of the acceleration process. We briefly summarize the state of the art in this area, and review some of the scaling studies presented in the literature. We also discuss some recent results, and projectedmore » scalings, related to a different acceleration mechanism for ions, based on the Radiation Pressure of an ultraintense laser pulse.« less
Yemets, Anatoliy V; Donchenko, Viktoriya I; Scrinick, Eugenia O
2018-01-01
Introduction: Experimental work is aimed at introducing theoretical and methodological foundations for the professional training of the future doctor. The aim: Identify the dynamics of quantitative and qualitative indicators of the readiness of a specialist in medicine. Materials and methods: The article presents the course and results of the experimental work of the conditions of forming the readiness of future specialists in medicine. Results: Our methodical bases for studying the disciplines of the general practice and specialized professional stage of experimental training of future physicians have been worked out. Conclusions: It is developed taking into account the peculiarities of future physician training of materials for various stages of experimental implementation in the educational process of higher medical educational institutions.
An analytical and experimental evaluation of a Fresnel lens solar concentrator
NASA Technical Reports Server (NTRS)
Hastings, L. J.; Allums, S. A.; Cosby, R. M.
1976-01-01
An analytical and experimental evaluation of line focusing Fresnel lenses with application potential in the 200 to 370 C range was studied. Analytical techniques were formulated to assess the solar transmission and imaging properties of a grooves down lens. Experimentation was based on a 56 cm wide, f/1.0 lens. A Sun tracking heliostat provided a nonmoving solar source. Measured data indicated more spreading at the profile base than analytically predicted, resulting in a peak concentration 18 percent lower than the computed peak of 57. The measured and computed transmittances were 85 and 87 percent, respectively. Preliminary testing with a subsequent lens indicated that modified manufacturing techniques corrected the profile spreading problem and should enable improved analytical experimental correlation.
Barbarich-Marsteller, Nicole C.; Underwood, Mark D.; Foltin, Richard W.; Myers, Michael M.; Walsh, B. Timothy; Barrett, Jeffrey S.; Marsteller, Douglas A.
2018-01-01
Objective Activity-based anorexia is a translational rodent model that results in severe weight loss, hyperactivity, and voluntary self-starvation. The goal of our investigation was to identify vulnerable and resistant phenotypes of activity-based anorexia in adolescent female rats. Method Sprague-Dawley rats were maintained under conditions of restricted access to food (N = 64; or unlimited access, N = 16) until experimental exit, predefined as a target weight loss of 30–35% or meeting predefined criteria for animal health. Nonlinear mixed effects statistical modeling was used to describe wheel running behavior, time to event analysis was used to assess experimental exit, and a regressive partitioning algorithm was used to classify phenotypes. Results Objective criteria were identified for distinguishing novel phenotypes of activity-based anorexia, including a vulnerable phenotype that conferred maximal hyperactivity, minimal food intake, and the shortest time to experimental exit, and a resistant phenotype that conferred minimal activity and the longest time to experimental exit. Discussion The identification of objective criteria for defining vulnerable and resistant phenotypes of activity-based anorexia in adolescent female rats provides an important framework for studying the neural mechanisms that promote vulnerability to or protection against the development of self-starvation and hyperactivity during adolescence. Ultimately, future studies using these novel phenotypes may provide important translational insights into the mechanisms that promote these maladaptive behaviors characteristic of anorexia nervosa. PMID:23853140
Barbarich-Marsteller, Nicole C; Underwood, Mark D; Foltin, Richard W; Myers, Michael M; Walsh, B Timothy; Barrett, Jeffrey S; Marsteller, Douglas A
2013-11-01
Activity-based anorexia is a translational rodent model that results in severe weight loss, hyperactivity, and voluntary self-starvation. The goal of our investigation was to identify vulnerable and resistant phenotypes of activity-based anorexia in adolescent female rats. Sprague-Dawley rats were maintained under conditions of restricted access to food (N = 64; or unlimited access, N = 16) until experimental exit, predefined as a target weight loss of 30-35% or meeting predefined criteria for animal health. Nonlinear mixed effects statistical modeling was used to describe wheel running behavior, time to event analysis was used to assess experimental exit, and a regressive partitioning algorithm was used to classify phenotypes. Objective criteria were identified for distinguishing novel phenotypes of activity-based anorexia, including a vulnerable phenotype that conferred maximal hyperactivity, minimal food intake, and the shortest time to experimental exit, and a resistant phenotype that conferred minimal activity and the longest time to experimental exit. The identification of objective criteria for defining vulnerable and resistant phenotypes of activity-based anorexia in adolescent female rats provides an important framework for studying the neural mechanisms that promote vulnerability to or protection against the development of self-starvation and hyperactivity during adolescence. Ultimately, future studies using these novel phenotypes may provide important translational insights into the mechanisms that promote these maladaptive behaviors characteristic of anorexia nervosa. Copyright © 2013 Wiley Periodicals, Inc.
A quasi-experimental study of after-event reviews and leadership development.
Derue, D Scott; Nahrgang, Jennifer D; Hollenbeck, John R; Workman, Kristina
2012-09-01
We examine how structured reflection through after-event reviews (AERs) promotes experience-based leadership development and how people's prior experiences and personality attributes influence the impact of AERs on leadership development. We test our hypotheses in a time-lagged, quasi-experimental study that followed 173 research participants for 9 months and across 4 distinct developmental experiences. Findings indicate that AERs have a positive effect on leadership development, and this effect is accentuated when people are conscientious, open to experience, and emotionally stable and have a rich base of prior developmental experiences.
Bolt, Hermann M; Başaran, Nurşen; Duydu, Yalçın
2012-01-01
The reproductive toxicity of boric acid and borates is a matter of current regulatory concern. Based on experimental studies in rats, no-observed-adverse-effect levels (NOAELs) were found to be 17.5 mg boron (B)/kg body weight (b.w.) for male fertility and 9.6 mg B/kg b.w. for developmental toxicity. Recently, occupational human field studies in highly exposed cohorts were reported from China and Turkey, with both studies showing negative results regarding male reproduction. A comparison of the conditions of these studies with the experimental NOAEL conditions are based on reported B blood levels, which is clearly superior to a scaling according to estimated B exposures. A comparison of estimated daily B exposure levels and measured B blood levels confirms the preference of biomonitoring data for a comparison of human field studies. In general, it appears that high environmental exposures to B are lower than possible high occupational exposures. The comparison reveals no contradiction between human and experimental reproductive toxicity data. It clearly appears that human B exposures, even in the highest exposed cohorts, are too low to reach the blood (and target tissue) concentrations that would be required to exert adverse effects on reproductive functions.
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.
A study of microstructural characteristics and differential thermal analysis of Ni-based superalloys
NASA Technical Reports Server (NTRS)
Aggarwal, M. D.; Lal, R. B.; Oyekenu, Samuel A.; Parr, Richard; Gentz, Stephen
1989-01-01
The objective of this work is to correlate the mechanical properties of the Ni-based superalloy MAR M246(Hf) used in the Space Shuttle Main Engine with its structural characteristics by systematic study of optical photomicrographs and differential thermal analysis. The authors developed a method of predicting the liquidus and solidus temperature of various nickel based superalloys (MAR-M247, Waspaloy, Udimet-41, polycrystalline and single crystals of CMSX-2 and CMSX-3) and comparing the predictions with the experimental differential thermal analysis (DTA) curves using Perkin-Elmer DTA 1700. The method of predicting these temperatures is based on the additive effect of the components dissolved in nickel. The results were compared with the experimental values.
Weak nanoscale chaos and anomalous relaxation in DNA
NASA Astrophysics Data System (ADS)
Mazur, Alexey K.
2017-06-01
Anomalous nonexponential relaxation in hydrated biomolecules is commonly attributed to the complexity of the free-energy landscapes, similarly to polymers and glasses. It was found recently that the hydrogen-bond breathing of terminal DNA base pairs exhibits a slow power-law relaxation attributable to weak Hamiltonian chaos, with parameters similar to experimental data. Here, the relationship is studied between this motion and spectroscopic signals measured in DNA with a small molecular photoprobe inserted into the base-pair stack. To this end, the earlier computational approach in combination with an analytical theory is applied to the experimental DNA fragment. It is found that the intensity of breathing dynamics is strongly increased in the internal base pairs that flank the photoprobe, with anomalous relaxation quantitatively close to that in terminal base pairs. A physical mechanism is proposed to explain the coupling between the relaxation of base-pair breathing and the experimental response signal. It is concluded that the algebraic relaxation observed experimentally is very likely a manifestation of weakly chaotic dynamics of hydrogen-bond breathing in the base pairs stacked to the photoprobe and that the weak nanoscale chaos can represent an ubiquitous hidden source of nonexponential relaxation in ultrafast spectroscopy.
Weak nanoscale chaos and anomalous relaxation in DNA.
Mazur, Alexey K
2017-06-01
Anomalous nonexponential relaxation in hydrated biomolecules is commonly attributed to the complexity of the free-energy landscapes, similarly to polymers and glasses. It was found recently that the hydrogen-bond breathing of terminal DNA base pairs exhibits a slow power-law relaxation attributable to weak Hamiltonian chaos, with parameters similar to experimental data. Here, the relationship is studied between this motion and spectroscopic signals measured in DNA with a small molecular photoprobe inserted into the base-pair stack. To this end, the earlier computational approach in combination with an analytical theory is applied to the experimental DNA fragment. It is found that the intensity of breathing dynamics is strongly increased in the internal base pairs that flank the photoprobe, with anomalous relaxation quantitatively close to that in terminal base pairs. A physical mechanism is proposed to explain the coupling between the relaxation of base-pair breathing and the experimental response signal. It is concluded that the algebraic relaxation observed experimentally is very likely a manifestation of weakly chaotic dynamics of hydrogen-bond breathing in the base pairs stacked to the photoprobe and that the weak nanoscale chaos can represent an ubiquitous hidden source of nonexponential relaxation in ultrafast spectroscopy.
Flexible 2D RF Nanoelectronics based on Layered Semiconductor Transistor (NBIT III)
2016-11-11
Experimental and computational studies in multidisciplinary fields of electrical, mechanical engineering , and materials science were conducted to achieve...plan for this project. Experimental and computational studies in multidisciplinary fields of electrical, mechanical engineering , and materials...electrostatic or physisorption gating, defect engineering , and substitutional doping during the growth. These methods result in uniform doping or composition
ERIC Educational Resources Information Center
Johnson, Afra Kaletta
2012-01-01
The purpose of this quasi-experimental study examines the effects of reading interventions for bi-lingual and bi-dialectal Broward County School District middle school children using research-based strategies combined with metacognitive and meta-comprehension frameworks. The experimental study reports findings on the effects of an 8-week…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ye, Tianyu; Mani, Ramesh G.; Wegscheider, Werner
2013-12-04
We present the results of a concurrent experimental study of microwave reflection and transport in the GaAs/AlGaAs two dimensional electron gas system and correlate observed features in the reflection with the observed transport features. The experimental results are compared with expectations based on theory.
A Musical Approach to Reading Fluency: An Experimental Study in First-Grade Classrooms
ERIC Educational Resources Information Center
Leguizamon, Daniel F.
2010-01-01
The purpose of this quantitative, quasi-experimental study was to investigate the relationship between Kodaly-based music instruction and reading fluency in first-grade classrooms. Reading fluency and overall reading achievement were measured for 109 participants at mid-point in the academic year pre- and post treatment. Tests were carried out to…
ERIC Educational Resources Information Center
De Smet, M.; Van Keer, H.; Valcke, M.
2008-01-01
Cross-age tutors were randomly assigned to one of the three tutor training conditions distinguished for the current study: (1) the labelling experimental condition, characterized by requirements to label their tutor interventions, based on the e-moderating model of Salmon; (2) the non-labelling experimental condition, focusing on tutor's acting…
Experimental study of the oscillation of spheres in an acoustic levitator.
Andrade, Marco A B; Pérez, Nicolás; Adamowski, Julio C
2014-10-01
The spontaneous oscillation of solid spheres in a single-axis acoustic levitator is experimentally investigated by using a high speed camera to record the position of the levitated sphere as a function of time. The oscillations in the axial and radial directions are systematically studied by changing the sphere density and the acoustic pressure amplitude. In order to interpret the experimental results, a simple model based on a spring-mass system is applied in the analysis of the sphere oscillatory behavior. This model requires the knowledge of the acoustic pressure distribution, which was obtained numerically by using a linear finite element method (FEM). Additionally, the linear acoustic pressure distribution obtained by FEM was compared with that measured with a laser Doppler vibrometer. The comparison between numerical and experimental pressure distributions shows good agreement for low values of pressure amplitude. When the pressure amplitude is increased, the acoustic pressure distribution becomes nonlinear, producing harmonics of the fundamental frequency. The experimental results of the spheres oscillations for low pressure amplitudes are consistent with the results predicted by the simple model based on a spring-mass system.
Validation of radiocarpal joint contact models based on images from a clinical MRI scanner.
Johnson, Joshua E; McIff, Terence E; Lee, Phil; Toby, E Bruce; Fischer, Kenneth J
2014-01-01
This study was undertaken to assess magnetic resonance imaging (MRI)-based radiocarpal surface contact models of functional loading in a clinical MRI scanner for future in vivo studies, by comparison with experimental measures from three cadaver forearm specimens. Experimental data were acquired using a Tekscan sensor during simulated light grasp. Magnetic resonance (MR) images were used to obtain model geometry and kinematics (image registration). Peak contact pressures (PPs) and average contact pressures (APs), contact forces and contact areas were determined in the radiolunate and radioscaphoid joints. Contact area was also measured directly from MR images acquired with load and compared with model data. Based on the validation criteria (within 25% of experimental data), out of the six articulations (three specimens with two articulations each), two met the criterion for AP (0%, 14%); one for peak pressure (20%); one for contact force (5%); four for contact area with respect to experiment (8%, 13%, 19% and 23%), and three contact areas met the criterion with respect to direct measurements (14%, 21% and 21%). Absolute differences between model and experimental PPs were reasonably low (within 2.5 MPa). Overall, the results indicate that MRI-based models generated from 3T clinical MR scanner appear sufficient to obtain clinically relevant data.
NASA Astrophysics Data System (ADS)
Bhattacharyya, Sumita; Volk, Trudi; Lumpe, Andrew
2009-06-01
This study examined the effects of an extensive inquiry-based field experience on pre service elementary teachers’ personal agency beliefs, a composite measure of context beliefs and capability beliefs related to teaching science. The research combined quantitative and qualitative approaches and included an experimental group that utilized the inquiry method and a control group that used traditional teaching methods. Pre- and post-test scores for the experimental and control groups were compared. The context beliefs of both groups showed no significant change as a result of the experience. However, the control group’s capability belief scores, lower than those of the experimental group to start with, declined significantly; the experimental group’s scores remained unchanged. Thus, the inquiry-based field experience led to an increase in personal agency beliefs. The qualitative data suggested a new hypothesis that there is a spiral relationship among teachers’ ability to establish communicative relationships with students, desire for personal growth and improvement, ability to implement multiple instructional strategies, and possession of substantive content knowledge. The study concludes that inquiry-based student teaching should be encouraged in the training of elementary school science teachers. However, the meaning and practice of the inquiry method should be clearly delineated to ensure its correct implementation in the classroom.
Gierthmühlen, Janne; Enax-Krumova, Elena K; Attal, Nadine; Bouhassira, Didier; Cruccu, Giorgio; Finnerup, Nanna B; Haanpää, Maija; Hansson, Per; Jensen, Troels S; Freynhagen, Rainer; Kennedy, Jeffrey D; Mainka, Tina; Rice, Andrew S C; Segerdahl, Märta; Sindrup, Søren H; Serra, Jordi; Tölle, Thomas; Treede, Rolf-Detlef; Baron, Ralf; Maier, Christoph
2015-11-01
Clinical and human experimental pain studies often include so-called "healthy" controls in investigations of sensory abnormalities, using quantitative sensory testing (QST) as an outcome measure. However, the criteria for what is considered "healthy" vary among the different studies and between study centers and investigators, partly explaining the high variability of the results. Therefore, several aspects should be considered during inclusion of healthy volunteers in QST-based trials to have homogenous groups of healthy controls with less variability between human experimental studies, so that results are less likely to be false negative or false positive because of subject-related factors. The EUROPAIN and NEUROPAIN consortia aimed to define factors influencing the variability in selection of healthy subjects in QST-based studies before the start of both projects and to give recommendations how to minimize it based on the current literature and expertise of the participants. The present suggestions for inclusion criteria of healthy volunteers into QST-based trials describe a 2-level approach including standardized questionnaires enabling the collection of relevant information on sociodemographic data, medical history, current health status, coping strategies in dealing with pain, and the motivation of the volunteer to participate in the study. These suggestions are believed to help researchers interpret their results in comparison with others and improve the quality of clinical studies including healthy volunteers as controls or in human experimental pain studies. They aim to reduce any confounding factors. Furthermore, the acquired information will allow post hoc analyses of variance for different potential influencing factors.
Solanki, Prem K; Rabin, Yoed
2018-01-01
This study presents experimental results and an analysis approach for polarized light effects associated with thermomechanical stress during cooling of glass promoting solutions, with applications to cryopreservation and tissue banking in a process known as vitrification. Polarized light means have been previously integrated into the cryomacroscope-a visualization device to detect physical effects associated with cryopreservation success, such as crystallization, fracture formation, and contamination. The experimental study concerns vitrification in a cuvette, which is a rectangular container. Polarized light modeling in the cuvette is based on subdividing the tridimensional (3D) domain into a series of planar (2D) problems, for which a mathematical solution is available in the literature. The current analysis is based on tracking the accumulated changes in light polarization and magnitude, as it passes through the sequence of planar problems. Results of this study show qualitative agreement in light intensity history and distribution between experimental data and simulated results. The simulated results help explaining differences between 2D and 3D effects in photoelasticity, most notably, the counterintuitive observation that high stress areas may correlate with low light intensity regions based on the particular experimental conditions. Finally, it is suggested that polarized-light analysis must always be accompanied by thermomechanical stress modeling in order to explain 3D effects.
Park, Kyung Im; Oh, Sangeun
2012-10-01
The purpose of this study was to verify effects of the Active Parenting Today (APT) program based on King's Goal Attainment Theory on parenting stress, parenting behavior, and parenting satisfaction in mothers of school-age children. This was a quasi-experimental study with a non-equivalent control group pre-post test design. Participants were 39 mothers of school-age children (19 in the experiment group and 20 in the control group) who were registered at two community children centers in G city. The experimental group received the APT program (2 hours/session/week) and telephone counseling (2 times/week) for 8 weeks. Data were analyzed using χ²-test, t-test, Fisher exact probability test, and ANCOVA with the SPSS/Win15.0 program. Parenting stress was significantly lower in the experimental group than in the control group. Positive parenting behavior and parenting satisfaction were significantly higher in the experimental group than in the control group. However, negative parenting behavior was not significantly different between the two groups. The results of this study indicate that the APT program based on King's Goal Attainment Theory is useful in reducing parenting stress, creating positive parenting behavior change, and promoting parenting satisfaction in mothers of school-age children.
2018-01-01
This study presents experimental results and an analysis approach for polarized light effects associated with thermomechanical stress during cooling of glass promoting solutions, with applications to cryopreservation and tissue banking in a process known as vitrification. Polarized light means have been previously integrated into the cryomacroscope—a visualization device to detect physical effects associated with cryopreservation success, such as crystallization, fracture formation, and contamination. The experimental study concerns vitrification in a cuvette, which is a rectangular container. Polarized light modeling in the cuvette is based on subdividing the tridimensional (3D) domain into a series of planar (2D) problems, for which a mathematical solution is available in the literature. The current analysis is based on tracking the accumulated changes in light polarization and magnitude, as it passes through the sequence of planar problems. Results of this study show qualitative agreement in light intensity history and distribution between experimental data and simulated results. The simulated results help explaining differences between 2D and 3D effects in photoelasticity, most notably, the counterintuitive observation that high stress areas may correlate with low light intensity regions based on the particular experimental conditions. Finally, it is suggested that polarized-light analysis must always be accompanied by thermomechanical stress modeling in order to explain 3D effects. PMID:29912973
Jalali, Farzad; Hasani, Alireza; Hashemi, Seyedeh Fatemeh; Kimiaei, Seyed Ali; Babaei, Ali
2018-06-01
Depression is one the most common mental disorders in prisons. People living with HIV are more likely to develop psychological difficulties when compared with the general population. This study aims to determine the efficacy of cognitive group therapy based on schema-focused approach in reducing depression in prisoners living with HIV. The design of this study was between-groups (or "independent measures"). It was conducted with pretest, posttest, and waiting list control group. The research population comprised all prisoners living with HIV in a men's prison in Iran. Based on voluntary desire, screening, and inclusion criteria, 42 prisoners living with HIV participated in this study. They were randomly assigned to an experimental group (21 prisoners) and waiting list control group (21 prisoners). The experimental group received 11 sessions of schema-focused cognitive group therapy, while the waiting list control group received the treatment after the completion of the study. The various groups were evaluated in terms of depression. ANCOVA models were employed to test the study hypotheses. Collated results indicated that depression was reduced among prisoners in the experimental group. Schema therapy (ST) could reduce depression among prisoners living with HIV/AIDS.
Ulbrecht, Jan S.; Hurley, Timothy; Mauger, David T.
2014-01-01
OBJECTIVE To assess the efficacy of in-shoe orthoses that were designed based on shape and barefoot plantar pressure in reducing the incidence of submetatarsal head plantar ulcers in people with diabetes, peripheral neuropathy, and a history of similar prior ulceration. RESEARCH DESIGN AND METHODS Single-blinded multicenter randomized controlled trial with subjects randomized to wear shape- and pressure-based orthoses (experimental, n = 66) or standard-of-care A5513 orthoses (control, n = 64). Patients were followed for 15 months, until a study end point (forefoot plantar ulcer or nonulcerative plantar forefoot lesion) or to study termination. Proportional hazards regression was used for analysis. RESULTS There was a trend in the composite primary end point (both ulcers and nonulcerative lesions) across the full follow-up period (P = 0.13) in favor of the experimental orthoses. This trend was due to a marked difference in ulcer occurrence (P = 0.007) but no difference in the rate of nonulcerative lesions (P = 0.76). At 180 days, the ulcer prevention effect of the experimental orthoses was already significant (P = 0.003) when compared with control, and the benefit of the experimental orthoses with respect to the composite end point was also significant (P = 0.042). The hazard ratio was 3.4 (95% CI 1.3–8.7) for the occurrence of a submetatarsal head plantar ulcer in the control compared with experimental arm over the duration of the study. CONCLUSIONS We conclude that shape- and barefoot plantar pressure–based orthoses were more effective in reducing submetatarsal head plantar ulcer recurrence than current standard-of-care orthoses, but they did not significantly reduce nonulcerative lesions. PMID:24760263
Ulbrecht, Jan S; Hurley, Timothy; Mauger, David T; Cavanagh, Peter R
2014-07-01
To assess the efficacy of in-shoe orthoses that were designed based on shape and barefoot plantar pressure in reducing the incidence of submetatarsal head plantar ulcers in people with diabetes, peripheral neuropathy, and a history of similar prior ulceration. Single-blinded multicenter randomized controlled trial with subjects randomized to wear shape- and pressure-based orthoses (experimental, n = 66) or standard-of-care A5513 orthoses (control, n = 64). Patients were followed for 15 months, until a study end point (forefoot plantar ulcer or nonulcerative plantar forefoot lesion) or to study termination. Proportional hazards regression was used for analysis. There was a trend in the composite primary end point (both ulcers and nonulcerative lesions) across the full follow-up period (P = 0.13) in favor of the experimental orthoses. This trend was due to a marked difference in ulcer occurrence (P = 0.007) but no difference in the rate of nonulcerative lesions (P = 0.76). At 180 days, the ulcer prevention effect of the experimental orthoses was already significant (P = 0.003) when compared with control, and the benefit of the experimental orthoses with respect to the composite end point was also significant (P = 0.042). The hazard ratio was 3.4 (95% CI 1.3-8.7) for the occurrence of a submetatarsal head plantar ulcer in the control compared with experimental arm over the duration of the study. We conclude that shape- and barefoot plantar pressure-based orthoses were more effective in reducing submetatarsal head plantar ulcer recurrence than current standard-of-care orthoses, but they did not significantly reduce nonulcerative lesions. © 2014 by the American Diabetes Association.
Experimental research of radio-frequency ion thruster
NASA Astrophysics Data System (ADS)
Antropov, N. N.; Akhmetzhanov, R. V.; Bogatyy, A. V.; Grishin, R. A.; Kozhevnikov, V. V.; Plokhikh, A. P.; Popov, G. A.; Khartov, S. A.
2016-12-01
The article is devoted to the research of low-power (300 W) radio-frequency ion thruster designed at the Moscow Aviation Institute. The main results of experimental research of the thruster using the testfacility power supplies and the power processing unit of their own design are presented. The dependence of the working fluid ionization cost on its mass flow rate at the constant ion beam current was investigated experimentally. The influence of the shape and material of the discharge chamber on the integral characteristics of the thruster was studied. The recommendations on the optimization of the thruster primary performance were developed based on the results of experimental studies.
Effectiveness of inquiry-based learning in an undergraduate exercise physiology course.
Nybo, Lars; May, Michael
2015-06-01
The present study was conducted to investigate the effects of changing a laboratory physiology course for undergraduate students from a traditional step-by-step guided structure to an inquiry-based approach. With this aim in mind, quantitative and qualitative evaluations of learning outcomes (individual subject-specific tests and group interviews) were performed for a laboratory course in cardiorespiratory exercise physiology that was conducted in one year with a traditional step-by-step guided manual (traditional course) and the next year completed with an inquiry-based structure (I-based course). The I-based course was a guided inquiry course where students had to design the experimental protocol and conduct their own study on the basis of certain predefined criteria (i.e., they should evaluate respiratory responses to submaximal and maximal exercise and provide indirect and direct measures of aerobic exercise capacity). The results indicated that the overall time spent on the experimental course as well as self-evaluated learning outcomes were similar across groups. However, students in the I-based course used more time in preparation (102 ± 5 min) than students in the traditional course (42 ± 3 min, P < 0.05), and 65 ± 5% students in the I-based course searched for additional literature before experimentation compared with only 2 ± 1% students in the traditional course. Furthermore, students in the I-based course achieved a higher (P < 0.05) average score on the quantitative test (45 ± 3%) compared with students in the traditional course (31 ± 4%). Although students were unfamiliar with cardiorespiratory exercise physiology and the experimental methods before the course, it appears that an inquiry-based approach rather than one that provides students with step-by-step instructions may benefit learning outcomes in a laboratory physiology course. Copyright © 2015 The American Physiological Society.
Choi, Jin Yi; Kang, Hyun Sook
2012-02-01
The purpose of this study was to identify the effects of a home based exercise program for patients with stomach cancer who were undergoing oral chemotherapy. The home-based exercise program was developed from the study findings of Winningham (1990) and data from the Korea Athletic Promotion Association (2007). The home-based exercise program consisted of 8 weeks of individual exercise education and exercise adherence strategy. Participants were 24 patients with stomach cancer who were undergoing oral chemotherapy following surgery in 2007 or 2008 at a university hospital in Seoul. Patients were randomly assigned to either the experimental group (11) or control group (13). The effects of the home-based exercise program were measured by level of cancer related fatigue, NK cell ratio, anxiety, and quality of life. Data were analyzed using SPSS/WIN 13.0 version. The degree of cancer related fatigue and anxiety in the experimental group decreased compared to the control group. The NK cell ratio and the degree of quality of life of experimental group increased while that of the control group decreased. This study result indicate the importance of exercise and provide empirical evidence for continuation of safe exercise for patients with cancer during their chemotherapy.
Robitaille, Yvonne; Fournier, Michel; Laforest, Sophie; Gauvin, Lise; Filiatrault, Johanne; Corriveau, Hélène
2012-08-01
To examine the effect of a fall prevention program offered under real-world conditions on balance maintenance several months after the program. To explore the program's impact on falls. A quasi-experimental study was conducted among community-dwelling seniors, with pre- and postintervention measures of balance performance and self-reported falls. Ten community-based organizations offered the intervention (98 participants) and 7 recruited participants to the study's control arm (102 participants). An earlier study examined balance immediately after the 12-week program. The present study focuses on the 12-month effect. Linear regression (balance) and negative binomial regression (falls) procedures were performed.falls. During the 12-month study period, experimental participants improved and maintained their balance as reflected by their scores on three performance tests. There was no evidence of an effect on falls.falls. Structured group exercise programs offered in community-based settings can maintain selected components of balance for several months after the program's end.
NASA Astrophysics Data System (ADS)
Chen, Tian-Yu; Chen, Yang; Yang, Hu-Jiang; Xiao, Jing-Hua; Hu, Gang
2018-03-01
Nowadays, massive amounts of data have been accumulated in various and wide fields, it has become today one of the central issues in interdisciplinary fields to analyze existing data and extract as much useful information as possible from data. It is often that the output data of systems are measurable while dynamic structures producing these data are hidden, and thus studies to reveal system structures by analyzing available data, i.e., reconstructions of systems become one of the most important tasks of information extractions. In the past, most of the works in this respect were based on theoretical analyses and numerical verifications. Direct analyses of experimental data are very rare. In physical science, most of the analyses of experimental setups were based on the first principles of physics laws, i.e., so-called top-down analyses. In this paper, we conducted an experiment of “Boer resonant instrument for forced vibration” (BRIFV) and inferred the dynamic structure of the experimental set purely from the analysis of the measurable experimental data, i.e., by applying the bottom-up strategy. Dynamics of the experimental set is strongly nonlinear and chaotic, and itʼs subjects to inevitable noises. We proposed to use high-order correlation computations to treat nonlinear dynamics; use two-time correlations to treat noise effects. By applying these approaches, we have successfully reconstructed the structure of the experimental setup, and the dynamic system reconstructed with the measured data reproduces good experimental results in a wide range of parameters.
ERIC Educational Resources Information Center
Lang'at, Edwin K.
2014-01-01
Purpose and Method of Study: The purpose of this study was to investigate teachers' self-perceived readiness to teach school-based HIV/AIDS Awareness and Prevention education in Kenyan primary schools based on their knowledge, attitudes and instructional confidence. This research utilized a non-experimental quantitative approach with a…
Submerged plant’s ability to present photosynthesis based on oxygen production
NASA Astrophysics Data System (ADS)
Supriatno, B.; Ulfa, K.
2018-05-01
This study aims to provide information about alternative experimental photosynthesis for experimental teaching practices in school in the coastal region. The research method was conducted experimentally by taking examples of Submerged plant in littoral area of Leuweng Sancang beach, Garut. Plant samples were given the same light intensity treatment, then the oxygen productivity was studied as an indicator of photosynthesis rate. The results showed that there were different photosynthetic rates in different types of submerged plants. Algae as submerged plants generally photosynthesize at high light intensity. However, there are also plants with photosynthesis in low light. The comparison between sea grass (Thallasia sp) with sea weed (Ulva sp) shows the difference in oxygen productivity. Submerged plants based on their ability to produce measurable oxygen can be utilized for experiments on photosynthesis learning.
Julie N. Symons; Dean H. K. Fairbanks; Carl N. Skinner
2008-01-01
This study utilizes forest stand structures and fuel profiles to evaluate the influence of different types of silvicultural treatments on fire severity in the Blacks Mountain Experimental Forest (BMEF), located within Lassen National Forest of northeastern California. We compare the severity of fire, assessed based on tree crown and bole scorch on 100 ha experimental...
An experimental study for a miniature Stirling refrigerator
NASA Technical Reports Server (NTRS)
Li, S.; Chen, G.; Huang, Z.; Zhang, F.; Cui, C.; Li, J.
1985-01-01
Experimental results of a miniature two-stage Stirling cryocooler are introduced. The influence of filling gas pressure and refrigeration temperature on the refrigerating capacity along with the relationship between parameters was measured. The valley pressure corresponding to the lowest refrigeration temperature and the cooldown time versus operating pressure are discussed. The coefficient of performance and thermodynamic efficiency of the cryocooler are calculated based on experimental data.
James M. Vose; Wayne T. Swank; Mary Beth Adams; Devendra Amatya; John Campbell; Sherri Johnson; Frederick J. Swanson; Randy Kolka; Ariel E. Lugo; Robert Musselman; Charles Rhoades
2014-01-01
Forest Service watershed-based Experimental Forests and Ranges (EFRs) have significantly advanced scientific knowledge on ecosystem structure and function through long-term monitoring and experimental research on hydrologic and biogeochemical cycling processes. Research conducted in the 1940s and 1950s began as âclassicâ paired watershed studies. The emergence of the...
ERIC Educational Resources Information Center
Blanco, Pedro J.
2009-01-01
This study examined the effectiveness of child centered play therapy (CCPT) with academically at-risk 1st graders. In this quasi-experimental design, twenty-one 1st grade students were assigned to the experimental group and 20 students were assigned to the no treatment control group. The children in the experimental group received two 30 minute…
NASA Astrophysics Data System (ADS)
Stavinskiy, A. V.
2017-09-01
A possibility of studying cold nuclear matter on the Nuclotron-NICA facility at baryonic densities characteristic of and higher than at the center of a neutron star is considered based on the data from cumulative processes. A special rare-event kinematic trigger for collisions of relativistic ions is proposed for effective selection of events accompanied by production of dense baryonic systems. Possible manifestations of new matter states under these unusual conditions and an experimental program for their study are discussed. Various experimental setups are proposed for these studies, and a possibility of using experimental setups at the Nuclotron-NICA facility for this purpose is considered.
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.
Metacognitive Skills Development: A Web-Based Approach in Higher Education
ERIC Educational Resources Information Center
Shen, Chun-Yi; Liu, Hsiu-Chuan
2011-01-01
Although there were studies that presented the applications of metacognitive skill training, the research on web-based metacognitive skills training are few. The purpose of this study is to design a web-based learning environment and further examine the effect of the web-based training. A pretest-posttest quasi-experimental design was used in this…
The Impact of Problem-Based Learning on Iranian EFL Learners' Speaking Proficiency
ERIC Educational Resources Information Center
Ansarian, Loghman; Adlipour, Ali Akbar; Saber, Mehrnoush Akhavan; Shafiei, Elmira
2016-01-01
The study investigated the effect of problem-based learning through cognition-based tasks on speaking proficiency of Iranian intermediate EFL learners in comparison to the effect of objective-based tasks. To this end, a true experimental research design was employed. Ninety five (N = 95) language learners studying at a language institute in the…
Thermal conductivity improvement in carbon nanoparticle doped PAO oil: An experimental study
NASA Astrophysics Data System (ADS)
Shaikh, S.; Lafdi, K.; Ponnappan, R.
2007-03-01
The present work involves a study on the thermal conductivity of nanoparticle-oil suspensions for three types of nanoparticles, namely, carbon nanotubes (CNTs), exfoliated graphite (EXG), and heat treated nanofibers (HTT) with PAO oil as the base fluid. To accomplish the above task, an experimental analysis is performed using a modern light flash technique (LFA 447) for measuring the thermal conductivity of the three types of nanofluids, for different loading of nanoparticles. The experimental results show a similar trend as observed in literature for nanofluids with a maximum enhancement of approximately 161% obtained for the CNT-PAO oil suspension. The overall percent enhancements for different volume fractions of the nanoparticles are highest for the CNT-based nanofluid, followed by the EXG and the HTT. The findings from this study for the three different types of carbon nanoparticles can have great potential in the field of thermal management.
The effect of dense gas dynamics on loss in ORC transonic turbines
NASA Astrophysics Data System (ADS)
Durá Galiana, FJ; Wheeler, APS; Ong, J.; Ventura, CA de M.
2017-03-01
This paper describes a number of recent investigations into the effect of dense gas dynamics on ORC transonic turbine performance. We describe a combination of experimental, analytical and computational studies which are used to determine how, in-particular, trailing-edge loss changes with choice of working fluid. A Ludwieg tube transient wind-tunnel is used to simulate a supersonic base flow which mimics an ORC turbine vane trailing-edge flow. Experimental measurements of wake profiles and trailing-edge base pressure with different working fluids are used to validate high-order CFD simulations. In order to capture the correct mixing in the base region, Large-Eddy Simulations (LES) are performed and verified against the experimental data by comparing the LES with different spatial and temporal resolutions. RANS and Detached-Eddy Simulation (DES) are also compared with experimental data. The effect of different modelling methods and working fluid on mixed-out loss is then determined. Current results point at LES predicting the closest agreement with experimental results, and dense gas effects are consistently predicted to increase loss.
NASA Astrophysics Data System (ADS)
Vincent, M.; Xolin, P.; Gevrey, A.-M.; Thiebaud, F.; Engels-Deutsch, M.; Ben Zineb, T.
2017-04-01
This paper presents an experimental and numerical study showing that single crystal shape memory alloy (SMA) Cu-based endodontic instruments can lead to equivalent mechanical performances compared to NiTi-based instruments besides their interesting biological properties. Following a previous finite element analysis (FEA) of single crystal CuAlBe endodontic instruments (Vincent et al 2015 J. Mater. Eng. Perform. 24 4128-39), prototypes with the determined geometrical parameters were machined and experimentally characterized in continuous rotation during a penetration/removal (P/R) protocol in artificial canals. The obtained mechanical responses were compared to responses of NiTi endodontic files in the same conditions. In addition, FEA was conducted and compared with the experimental results to validate the adopted modeling and to evaluate the local quantities inside the instrument as the stress state and the distribution of volume fraction of martensite. The obtained results highlight that single crystal CuAlBe SMA prototypes show equivalent mechanical responses to its NiTi homologous prototypes in the same P/R experimental conditions.
Joint research effort on vibrations of twisted plates, phase 1: Final results
NASA Technical Reports Server (NTRS)
Kielb, R. E.; Leissa, A. W.; Macbain, J. C.; Carney, K. S.
1985-01-01
The complete theoretical and experimental results of the first phase of a joint government/industry/university research study on the vibration characteristics of twisted cantilever plates are given. The study is conducted to generate an experimental data base and to compare many different theoretical methods with each other and with the experimental results. Plates with aspect ratios, thickness ratios, and twist angles representative of current gas turbine engine blading are investigated. The theoretical results are generated by numerous finite element, shell, and beam analysis methods. The experimental results are obtained by precision matching a set of twisted plates and testing them at two laboratories. The second and final phase of the study will concern the effects of rotation.
Assessment of semi-active friction dampers
NASA Astrophysics Data System (ADS)
dos Santos, Marcelo Braga; Coelho, Humberto Tronconi; Lepore Neto, Francisco Paulo; Mafhoud, Jarir
2017-09-01
The use of friction dampers has been widely proposed for a variety of mechanical systems for which applying viscoelastic materials, fluid based dampers or other viscous dampers is impossible. An important example is the application of friction dampers in aircraft engines to reduce the blades' vibration amplitudes. In most cases, friction dampers have been studied in a passive manner, but significant improvements can be achieved by controlling the normal force in the contact region. The aim of this paper is to present and study five control strategies for friction dampers based on three different hysteresis cycles by using the Harmonic Balance Method (HBM), a numerical and experimental analysis. The first control strategy uses the friction force as a resistance when the system is deviating from its equilibrium position. The second control strategy maximizes the energy removal in each harmonic oscillation cycle by calculating the optimal normal force based on the last displacement peak. The third control strategy combines the first strategy with the homogenous modulation of the friction force. Finally, the last two strategies attempt to predict the system's movement based on its velocity and acceleration and our knowledge of its physical properties. Numerical and experimental studies are performed with these five strategies, which define the performance metrics. The experimental testing rig is fully identified and its parameters are used for numerical simulations. The obtained results show the satisfactory performance of the friction damper and selected strategy and the suitable agreement between the numerical and experimental results.
NASA Astrophysics Data System (ADS)
Aissaoui, Tayeb; Benguerba, Yacine; AlNashef, Inas M.
2017-08-01
The in-silico combination mechanism of triethylene glycol based DESs has been studied. COSMO-RS and graphical user interface TmoleX software were used to predict the interaction mechanism of hydrogen bond donors (HBDs) with hydrogen bond acceptors (HBA) to form DESs. The predicted IR results were compared with the previously reported experimental FT-IR analysis for the same studied DESs. The sigma profiles for the HBD, HBAs and formed DESs were interpreted to identify qualitatively molecular properties like polarity or hydrogen bonding donor and acceptor abilities. The predicted physicochemical properties reported in this study were in good agreement with experimental ones.
Fan, Ang-Xiao; Dakpé, Stéphanie; Dao, Tien Tuan; Pouletaut, Philippe; Rachik, Mohamed; Ho Ba Tho, Marie Christine
2017-07-01
Finite element simulation of facial mimics provides objective indicators about soft tissue functions for improving diagnosis, treatment and follow-up of facial disorders. There is a lack of in vivo experimental data for model development and validation. In this study, the contribution of the paired Zygomaticus Major (ZM) muscle contraction on the facial mimics was investigated using in vivo experimental data derived from MRI. Maximal relative differences of 7.7% and 37% were noted between MRI-based measurements and numerical outcomes for ZM and skin deformation behaviors respectively. This study opens a new direction to simulate facial mimics with in vivo data.
Rossi, Michael R.; Tanaka, Daigo; Shimada, Kenji; Rabin, Yoed
2009-01-01
The current study focuses on experimentally validating a planning scheme based on the so-called bubble-packing method. This study is a part of an ongoing effort to develop computerized planning tools for cryosurgery, where bubble packing has been previously developed as a means to find an initial, uniform distribution of cryoprobes within a given domain; the so-called force-field analogy was then used to move cryoprobes to their optimum layout. However, due to the high quality of the cryoprobes’ distribution, suggested by bubble packing and its low computational cost, it has been argued that a planning scheme based solely on bubble packing may be more clinically relevant. To test this argument, an experimental validation is performed on a simulated cross-section of the prostate, using gelatin solution as a phantom material, proprietary liquid-nitrogen based cryoprobes, and a cryoheater to simulate urethral warming. Experimental results are compared with numerically simulated temperature histories resulting from planning. Results indicate an average disagreement of 0.8 mm in identifying the freezing front location, which is an acceptable level of uncertainty in the context of prostate cryosurgery imaging. PMID:19885373
NASA Astrophysics Data System (ADS)
Maurya, R. C.; Malik, B. A.; Mir, J. M.; Vishwakarma, P. K.; Rajak, D. K.; Jain, N.
2015-11-01
The present report pertains to synthesis and combined experimental-DFT studies of a series of four novel mixed-ligand complexes of cobalt(II) of the general composition [Co(dha)(L)(H2O)2], where dhaH = dehydroacetic acid, LH = β-ketoenolates viz., o-acetoacetotoluidide (o-aatdH), o-acetoacetanisidide (o-aansH), acetylacetone (acacH) or 1-benzoylacetone (1-bac). The resulting complexes were formulated based on elemental analysis, molar conductance, magnetic measurements, mass spectrometric, IR, electronic, electron spin resonance and cyclic voltammetric studies. The TGA based thermal behavior of one representative complex was evaluated. Molecular geometry optimizations and vibrational frequency calculations have been performed with Gaussian 09 software package by using density functional theory (DFT) methods with B3LYP/LANL2MB combination for dhaH and one of its complexes, [Co(dha)(1-bac)(H2O)2]. Theoretical data has been found in an excellent agreement with the experimental results. Based on experimental and theoretical data, suitable trans-octahedral structure has been proposed for the present class of complexes. Moreover, the complexes also showed a satisfactory antibacterial activity.
Experimental and AI-based numerical modeling of contaminant transport in porous media
NASA Astrophysics Data System (ADS)
Nourani, Vahid; Mousavi, Shahram; Sadikoglu, Fahreddin; Singh, Vijay P.
2017-10-01
This study developed a new hybrid artificial intelligence (AI)-meshless approach for modeling contaminant transport in porous media. The key innovation of the proposed approach is that both black box and physically-based models are combined for modeling contaminant transport. The effectiveness of the approach was evaluated using experimental and real world data. Artificial neural network (ANN) and adaptive neuro-fuzzy inference system (ANFIS) were calibrated to predict temporal contaminant concentrations (CCs), and the effect of noisy and de-noised data on the model performance was evaluated. Then, considering the predicted CCs at test points (TPs, in experimental study) and piezometers (in Myandoab plain) as interior conditions, the multiquadric radial basis function (MQ-RBF), as a meshless approach which solves partial differential equation (PDE) of contaminant transport in porous media, was employed to estimate the CC values at any point within the study area where there was no TP or piezometer. Optimal values of the dispersion coefficient in the advection-dispersion PDE and shape coefficient of MQ-RBF were determined using the imperialist competitive algorithm. In temporal contaminant transport modeling, de-noised data enhanced the performance of ANN and ANFIS methods in terms of the determination coefficient, up to 6 and 5%, respectively, in the experimental study and up to 39 and 18%, respectively, in the field study. Results showed that the efficiency of ANFIS-meshless model was more than ANN-meshless model up to 2 and 13% in the experimental and field studies, respectively.
ERIC Educational Resources Information Center
Korkmaz, Özgen
2016-01-01
The aim of this study was to investigate the effect of the Scratch and Lego Mindstorms Ev3 programming activities on academic achievement with respect to computer programming, and on the problem-solving and logical-mathematical thinking skills of students. This study was a semi-experimental, pretest-posttest study with two experimental groups and…
Scientific Reasoning across Different Domains.
ERIC Educational Resources Information Center
Glaser, Robert; And Others
This study seeks to establish which scientific reasoning skills are primarily domain-general and which appear to be domain-specific. The subjects, 12 university undergraduates, each participated in self-directed experimentation with three different content domains. The experimentation contexts were computer-based laboratories in d.c. circuits…
Space Weather Studies Using Ground-based Experimental Complex in Kazakhstan
NASA Astrophysics Data System (ADS)
Kryakunova, O.; Yakovets, A.; Monstein, C.; Nikolayevskiy, N.; Zhumabayev, B.; Gordienko, G.; Andreyev, A.; Malimbayev, A.; Levin, Yu.; Salikhov, N.; Sokolova, O.; Tsepakina, I.
2015-12-01
Kazakhstan ground-based experimental complex for space weather study is situated near Almaty. Results of space environment monitoring are accessible via Internet on the web-site of the Institute of Ionosphere (http://www.ionos.kz/?q=en/node/21) in real time. There is a complex database with hourly data of cosmic ray intensity, geomagnetic field intensity, and solar radio flux at 10.7 cm and 27.8 cm wavelengths. Several studies using those data are reported. They are an estimation of speed of a coronal mass ejection, a study of large scale traveling distrubances, an analysis of geomagnetically induced currents using the geomagnetic field data, and a solar energetic proton event on 27 January 2012.
Effects of a System Thinking-Based Simulation Program for Congestive Heart Failure.
Kim, Hyeon-Young; Yun, Eun Kyoung
2018-03-01
This study evaluated a system thinking-based simulation program for the care of patients with congestive heart failure. Participants were 67 undergraduate nursing students from a nursing college in Seoul, South Korea. The experimental group was given a 4-hour system-thinking program and a 2-hour simulation program, whereas the control group had a 4-hour case study and a 2-hour simulation program. There were significant improvements in critical thinking in both groups, but no significant group differences between educational methods (F = 3.26, P = .076). Problem-solving ability in the experimental group was significantly higher than in the control group (F = 5.04, P = .028). Clinical competency skills in the experimental group were higher than in the control group (t = 2.12, P = .038). A system thinking-based simulation program is a more effective learning method in terms of problem-solving ability and clinical competency skills compared to the existing simulation program. Further research using a longitudinal study is needed to test the long-term effect of the intervention and apply it to the nursing curriculum.
NASA Astrophysics Data System (ADS)
Lee, Bo Mi; Loh, Kenneth J.
2017-04-01
Carbon nanotubes can be randomly deposited in polymer thin film matrices to form nanocomposite strain sensors. However, a computational framework that enables the direct design of these nanocomposite thin films is still lacking. The objective of this study is to derive an experimentally validated and two-dimensional numerical model of carbon nanotube-based thin film strain sensors. This study consisted of two parts. First, multi-walled carbon nanotube (MWCNT)-Pluronic strain sensors were fabricated using vacuum filtration, and their physical, electrical, and electromechanical properties were evaluated. Second, scanning electron microscope images of the films were used for identifying topological features of the percolated MWCNT network, where the information obtained was then utilized for developing the numerical model. Validation of the numerical model was achieved by ensuring that the area ratios (of MWCNTs relative to the polymer matrix) were equivalent for both the experimental and modeled cases. Strain sensing behavior of the percolation-based model was simulated and then compared to experimental test results.
ERIC Educational Resources Information Center
Pandya, Samta P.
2018-01-01
Based on a one-year longitudinal experimental study with 3,782 kindergarten school children across 15 countries, this article examines the association between prayer and happiness. Results show that the post-test scores on the faces scale were higher for the participant group who had taken the prayer lessons vis-à-vis the comparison group.…
NASA Astrophysics Data System (ADS)
Acar Sesen, Burcin; Tarhan, Leman
2013-02-01
This study aimed to investigate the effects of inquiry-based laboratory activities on high school students' understanding of electrochemistry and attitudes towards chemistry and laboratory work. The participants were 62 high school students (average age 17 years) in an urban public high school in Turkey. Students were assigned to experimental ( N = 30) and control groups ( N = 32). The experimental group was taught using inquiry-based laboratory activities developed by the researchers and the control group was instructed using traditional laboratory activities. The results of the study indicated that instruction based on inquiry-based laboratory activities caused a significantly better acquisition of scientific concepts related to electrochemistry, and produced significantly higher positive attitudes towards chemistry and laboratory. In the light of the findings, it is suggested that inquiry-based laboratory activities should be developed and applied to promote students' understanding in chemistry subjects and to improve their positive attitudes.
Bröder, Arndt; Malejka, Simone
2017-07-01
The experimental manipulation of response biases in recognition-memory tests is an important means for testing recognition models and for estimating their parameters. The textbook manipulations for binary-response formats either vary the payoff scheme or the base rate of targets in the recognition test, with the latter being the more frequently applied procedure. However, some published studies reverted to implying different base rates by instruction rather than actually changing them. Aside from unnecessarily deceiving participants, this procedure may lead to cognitive conflicts that prompt response strategies unknown to the experimenter. To test our objection, implied base rates were compared to actual base rates in a recognition experiment followed by a post-experimental interview to assess participants' response strategies. The behavioural data show that recognition-memory performance was estimated to be lower in the implied base-rate condition. The interview data demonstrate that participants used various second-order response strategies that jeopardise the interpretability of the recognition data. We thus advice researchers against substituting actual base rates with implied base rates.
NASA Astrophysics Data System (ADS)
Mourid, Amina; El Alami, Mustapha
2018-05-01
In this paper, we present a comparative thermal study of the usual insulation materials used in the building as well as the innovate one like phase change materials (PCMs). Both experimental study and numerical approach were applied in this work for summer season. In the experimental study the PCM was installed on the outer surface on the ceiling of one of two full-scale rooms located at FSAC, Casablanca. A simulation model was performed with TRNSYS’17 software. We have established as a criterion of comparison the internal temperatures. An economic study also has been carried out. Based on this latter, that the PCM is most efficient.
An innovative seismic bracing system based on a superelastic shape memory alloy ring
NASA Astrophysics Data System (ADS)
Gao, Nan; Jeon, Jong-Su; Hodgson, Darel E.; DesRoches, Reginald
2016-05-01
Shape memory alloys (SMAs) have great potential in seismic applications because of their remarkable superelasticity. Seismic bracing systems based on SMAs can mitigate the damage caused by earthquakes. The current study investigates a bracing system based on an SMA ring which is capable of both re-centering and energy dissipation. This lateral force resisting system is a cross-braced system consisting of an SMA ring and four tension-only cable assemblies, which can be applied to both new construction and seismic retrofit. The performance of this bracing system is examined through a quasi-static cyclic loading test and finite element (FE) analysis. This paper describes the experimental design in detail, discusses the experimental results, compares the performance with other bracing systems based on SMAs, and presents an Abaqus FE model calibrated on the basis of experimental results to simulate the superelastic behavior of the SMA ring. The experimental results indicate that the seismic performance of this system is promising in terms of damping and re-centering. The FE model can be used in the simulation of building structures using the proposed bracing system.
Lee, Kyung Eun
2018-04-01
An important goal of nursing education is helping students achieve core competencies efficiently. One proposed way of improving nursing education is team-based learning (TBL). The aim of this study was to assess the comparative effectiveness of TBL and lecture-style classes in terms of teaching core competencies in nursing education, which include clinical competence skills, problem-solving ability, communication competencies, critical thinking ability, and self-leadership. This quasi-experimental study enrolled 183 students as participants, with 95 and 88 in the experimental and control groups, respectively. These two groups attended 6 hours (2 hours weekly for 3 weeks) of TBL and lecture-style classes, respectively. Differences in core competencies between the two groups were compared before and after the intervention. The experimental group achieved significantly higher scores for clinical competence skills, communication competence, critical thinking ability, and self-leadership at posttest than at pretest, whereas the control group achieved significantly higher scores for clinical competence skills and critical thinking ability at posttest than at pretest. After the intervention, the experimental group had significantly better clinical competence skills, communication competence, and self-leadership than the control group. TBL is an effective approach method to teaching core competencies in nursing education.
NASA Astrophysics Data System (ADS)
Venables, Jeffrey M.
The literature on microcomputer-based laboratories (MBL) lacks quantitative studies that measure the effect of MBL on student achievement. The purpose of this study was to investigate the effect of MBL systems on the achievement of high school chemistry students. The first research question examined the effect of MBL systems on student achievement in high school chemistry laboratories. The second question analyzed the effect of MBL systems on the academic achievement of students of different genders, ethnicities, and socioeconomic backgrounds. This quasi-experimental quantitative research study evaluated the effects of MBL on student achievement in high school chemistry. The sample consisted of 124 college preparatory chemistry students at two high schools in a South Carolina school district. There were 42 participants in the experimental group and 82 participants in the control group. Both experimental and groups completed a pre- and post-test with MBL being the independent variable. The mean difference score for the experimental group was compared to that of the control group using an independent-measures t test and an analysis of variance. For the second research question, results were analyzed using a two-factor analysis of variance. Participant scores were broken down by gender, ethnicity, and socioeconomic status in order to identify potential differences. The results revealed no significant differences between the experimental and control groups, and no significant differences in effects of MBL on different segments of the population. Future studies should examine students using MBL for longer durations than one unit of study. As society continues to make technological advances, the effective assessment and implementation of technology resources for the classroom are becoming increasingly important.
Bunker, Alex; Magarkar, Aniket; Viitala, Tapani
2016-10-01
Combined experimental and computational studies of lipid membranes and liposomes, with the aim to attain mechanistic understanding, result in a synergy that makes possible the rational design of liposomal drug delivery system (LDS) based therapies. The LDS is the leading form of nanoscale drug delivery platform, an avenue in drug research, known as "nanomedicine", that holds the promise to transcend the current paradigm of drug development that has led to diminishing returns. Unfortunately this field of research has, so far, been far more successful in generating publications than new drug therapies. This partly results from the trial and error based methodologies used. We discuss experimental techniques capable of obtaining mechanistic insight into LDS structure and behavior. Insight obtained purely experimentally is, however, limited; computational modeling using molecular dynamics simulation can provide insight not otherwise available. We review computational research, that makes use of the multiscale modeling paradigm, simulating the phospholipid membrane with all atom resolution and the entire liposome with coarse grained models. We discuss in greater detail the computational modeling of liposome PEGylation. Overall, we wish to convey the power that lies in the combined use of experimental and computational methodologies; we hope to provide a roadmap for the rational design of LDS based therapies. Computational modeling is able to provide mechanistic insight that explains the context of experimental results and can also take the lead and inspire new directions for experimental research into LDS development. This article is part of a Special Issue entitled: Biosimulations edited by Ilpo Vattulainen and Tomasz Róg. Copyright © 2016 Elsevier B.V. All rights reserved.
Theoretical and experimental study of a thruster discharging a weight
NASA Astrophysics Data System (ADS)
Michaels, Dan; Gany, Alon
2014-06-01
An innovative concept for a rocket type thruster that can be beneficial for spacecraft trajectory corrections and station keeping was investigated both experimentally and theoretically. It may also be useful for divert and attitude control systems (DACS). The thruster is based on a combustion chamber discharging a weight through an exhaust tube. Calculations with granular double-base propellant and a solid ejected weight reveal that a specific impulse based on the propellant mass of well above 400 s can be obtained. An experimental thruster was built in order to demonstrate the new idea and validate the model. The thruster impulse was measured both directly with a load cell and indirectly by using a pressure transducer and high speed photography of the weight as it exits the tube, with both ways producing very similar total impulse measurement. The good correspondence between the computations and the measured data validates the model as a useful tool for studying and designing such a thruster.
NASA Astrophysics Data System (ADS)
Baumwoll, Alma Aron
As education and neuroscience begin to merge, creating the new field of brain-based education, teachers are working to integrate scientific research into the classroom. While working to improve my own teaching, I developed a lesson plan to teach mitosis and meiosis through movement. My thesis reviews education theory and neuroscience to support using movement as a teaching tool in high-level, subject-based classrooms. I then outline my lesson plan and present my investigations of its effectiveness as demonstrated through short-term memory, long-term memory, and students' personal responses to the class. Two experiments were completed with biology lab sections at Northeastern University between 2009 and 2012; I taught my lesson to experimental groups while control groups learned through video-based lessons. The short-term study showed significant improvement in both the grades and enjoyment of the experimental groups. The long-term, retroactive study yielded no significant data, possibly due to weaknesses in the experimental design.
Intuitive web-based experimental design for high-throughput biomedical data.
Friedrich, Andreas; Kenar, Erhan; Kohlbacher, Oliver; Nahnsen, Sven
2015-01-01
Big data bioinformatics aims at drawing biological conclusions from huge and complex biological datasets. Added value from the analysis of big data, however, is only possible if the data is accompanied by accurate metadata annotation. Particularly in high-throughput experiments intelligent approaches are needed to keep track of the experimental design, including the conditions that are studied as well as information that might be interesting for failure analysis or further experiments in the future. In addition to the management of this information, means for an integrated design and interfaces for structured data annotation are urgently needed by researchers. Here, we propose a factor-based experimental design approach that enables scientists to easily create large-scale experiments with the help of a web-based system. We present a novel implementation of a web-based interface allowing the collection of arbitrary metadata. To exchange and edit information we provide a spreadsheet-based, humanly readable format. Subsequently, sample sheets with identifiers and metainformation for data generation facilities can be created. Data files created after measurement of the samples can be uploaded to a datastore, where they are automatically linked to the previously created experimental design model.
NASA Astrophysics Data System (ADS)
Yenni, Rita; Hernani, Widodo, Ari
2017-05-01
The study aims to determine the increasing of students' science literacy skills on content aspects and competency of science by using Integrated Science teaching materials based Socio-scientific Issues (SSI) for environmental pollution theme. The method used in the study is quasi-experiment with nonequivalent pretest and posttest control group design. The students of experimental class used teaching materials based SSI, whereas the students of control class were still using the usual textbooks. The result of this study showed a significant difference between the value of N-gain of experimental class and control class, whichalso occurred in every indicator of content aspects and competency of science. This result indicates that using of Integrated Science teaching materials based SSI can improve content aspect and competency of science and can be used as teaching materials alternative in teaching of Integrated Science.
McNabb, Jaimie; Gray, Rob
2016-01-01
Previous research on smart phone use while driving has primarily focused on phone calls and texting. Drivers are now increasingly using their phone for other activities during driving, in particular social media, which have different cognitive demands. The present study compared the effects of four different smart phone tasks on car-following performance in a driving simulator. Phone tasks were chosen that vary across two factors: interaction medium (text vs image) and task pacing (self-paced vs experimenter-paced) and were as follows: Text messaging with the experimenter (text/other-paced), reading Facebook posts (text/self-paced), exchanging photos with the experimenter via Snapchat (image, experimenter -paced), and viewing updates on Instagram (image, experimenter -paced). Drivers also performed a driving only baseline. Brake reaction times (BRTs) were significantly greater in the text-based conditions (Mean = 1.16 s) as compared to both the image-based conditions (Mean = 0.92 s) and the baseline (0.88 s). There was no significant difference between BRTs in the image-based and baseline conditions and there was no significant effect of task-pacing. Similar results were obtained for Time Headway variability. These results are consistent with the picture superiority effect found in memory research and suggest that image-based interfaces could provide safer ways to “stay connected” while driving than text-based interfaces. PMID:26886099
McNabb, Jaimie; Gray, Rob
2016-01-01
Previous research on smart phone use while driving has primarily focused on phone calls and texting. Drivers are now increasingly using their phone for other activities during driving, in particular social media, which have different cognitive demands. The present study compared the effects of four different smart phone tasks on car-following performance in a driving simulator. Phone tasks were chosen that vary across two factors: interaction medium (text vs image) and task pacing (self-paced vs experimenter-paced) and were as follows: Text messaging with the experimenter (text/other-paced), reading Facebook posts (text/self-paced), exchanging photos with the experimenter via Snapchat (image, experimenter-paced), and viewing updates on Instagram (image, experimenter-paced). Drivers also performed a driving only baseline. Brake reaction times (BRTs) were significantly greater in the text-based conditions (Mean = 1.16 s) as compared to both the image-based conditions (Mean = 0.92 s) and the baseline (0.88 s). There was no significant difference between BRTs in the image-based and baseline conditions and there was no significant effect of task-pacing. Similar results were obtained for Time Headway variability. These results are consistent with the picture superiority effect found in memory research and suggest that image-based interfaces could provide safer ways to "stay connected" while driving than text-based interfaces.
Conduction-driven cooling of LED-based automotive LED lighting systems for abating local hot spots
NASA Astrophysics Data System (ADS)
Saati, Ferina; Arik, Mehmet
2018-02-01
Light-emitting diode (LED)-based automotive lighting systems pose unique challenges, such as dual-side packaging (front side for LEDs and back side for driver electronics circuit), size, harsh ambient, and cooling. Packaging for automotive lighting applications combining the advanced printed circuit board (PCB) technology with a multifunctional LED-based board is investigated with a focus on the effect of thermal conduction-based cooling for hot spot abatement. A baseline study with a flame retardant 4 technology, commonly known as FR4 PCB, is first compared with a metal-core PCB technology, both experimentally and computationally. The double-sided advanced PCB that houses both electronics and LEDs is then investigated computationally and experimentally compared with the baseline FR4 PCB. Computational models are first developed with a commercial computational fluid dynamics software and are followed by an advanced PCB technology based on embedded heat pipes, which is computationally and experimentally studied. Then, attention is turned to studying different heat pipe orientations and heat pipe placements on the board. Results show that conventional FR4-based light engines experience local hot spots (ΔT>50°C) while advanced PCB technology based on heat pipes and thermal spreaders eliminates these local hot spots (ΔT<10°C), leading to a higher lumen extraction with improved reliability. Finally, possible design options are presented with embedded heat pipe structures that further improve the PCB performance.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Leszczynski, Jerzy; Sponer, Judit; Sponer, Jiri
Recent experimental studies on the Watson Crick type base pairing of triazine and aminopyrimidine derivatives suggest that acid/base properties of the constituent bases might be related to the duplex stabilities measured in solution. Herein we use high-level quantum chemical calculations and molecular dynamics simulations to evaluate the base pairing and stacking interactions of seven selected base pairs, which are common in that they are stabilized by two NH O hydrogen bonds separated by one NH N hydrogen bond. We show that neither the base pairing nor the base stacking interaction energies correlate with the reported pKa data of the basesmore » and the melting points of the duplexes. This suggests that the experimentally observed correlation between the melting point data of the duplexes and the pKa values of the constituent bases is not rooted in the intrinsic base pairing and stacking properties. The physical chemistry origin of the observed experimental correlation thus remains unexplained and requires further investigations. In addition, since our calculations are carried out with extrapolation to the complete basis set of atomic orbitals and with inclusion of higher electron correlation effects, they provide reference data for stacking and base pairing energies of non-natural bases.« less
Sun, Chunran; Wang, Muguang; Jian, Shuisheng
2017-08-21
In this paper, a novel quasi-fan Solc structure filter based on elliptical-core spun fiber for twist sensing has been experimentally investigated and theoretically analyzed. The discrete model of spun fiber has been built to analyze the transmission characteristics of proposed sensor. Both experimental and simulated results indicate that the extinction ratio of the comb spectrum based on quasi-fan Solc birefringent fiber filter varies with twist angle and agrees well with each other. Based on the intensity modulation, the proposed twist sensor exhibits a high sensitivity of 0.02219 dB/(°/m). Moreover, thanks to the invariability of the fiber birefringence and the state of polarization of the input light, the proposed twist sensor has a very low temperature and strain sensitivity, which can avoid the cross-sensitivity problem existing in most twist sensors.
James M. Vose; Wayne T. Swank; Mary Beth Adams; Devendra Amatya; John Campbell; Sherri Johnson; Frederick J. Swanson; Randy Kolka; Ariel E. Lugo; Robert Musselman; Charles Rhoades
2014-01-01
Forest Service watershed-based Experimental Forests and Ranges (EFRs) have significantly advanced scientific knowledge on ecosystem structure and function through long-term monitoring and experimental research on hydrologic and biogeochemical cycling processes. Research conducted in the 1940s and 1950s began as âclassicâ paired watershed studies. The emergence of the...
NASA Astrophysics Data System (ADS)
Kisała, Dawid; Tekieli, Marcin
2017-10-01
Steel plate-concrete composite structures are a new innovative design concept in which a thin steel plate is attached to the reinforced concrete beam by means of welded headed studs. The comparison between experimental studies and theoretical analysis of this type of structures shows that their behaviour is dependent on the load-slip relationship of the shear connectors used to ensure sufficient bond between the concrete and steel parts of the structure. The aim of this paper is to describe an experimental study on headed studs used in steel plate-concrete composite structures. Push-out tests were carried out to investigate the behaviour of shear connectors. The test specimens were prepared according to standard push-out tests, however, instead of I-beam, a steel plate 16 mm thick was used to better reflect the conditions in the real structure. The test specimens were produced in two batches using concrete with significantly different compressive strength. The experimental study was carried out on twelve specimens. Besides the traditional measurements based on LVDT sensors, optical measurements based on the digital image correlation method (DIC) and pattern tracking methods were used. DIC is a full-field contactless optical method for measuring displacements in experimental testing, based on the correlation of the digital images taken during test execution. With respect to conventional methods, optical measurements offer a wider scope of results and can give more information about the material or construction behaviour during the test. The ultimate load capacity and load-slip curves obtained from the experiments were compared with the values calculated based on Eurocodes, American and Chinese design specifications. It was observed that the use of the relationships developed for the traditional steel-concrete composite structures is justified in the case of ultimate load capacity of shear connectors in steel plate-concrete composite structures.
Music and suicidality: a quantitative review and extension.
Stack, Steven; Lester, David; Rosenberg, Jonathan S
2012-12-01
This article provides the first quantitative review of the literature on music and suicidality. Multivariate logistic regression techniques are applied to 90 findings from 21 studies. Investigations employing ecological data on suicide completions are 19.2 times more apt than other studies to report a link between music and suicide. More recent and studies with large samples are also more apt than their counterparts to report significant results. Further, none of the studies based on experimental research designs found a link between music and suicide ideation, prompting us to do a brief content analysis of 24 suicide songs versus 24 nonsuicide songs from the same album. Using Linguistic Inquiry and Word Count software, we found no difference in the content of the suicide songs and controls, including the percentage of sad words, negative affect, and mentions of death, thus providing an explanation for nonfindings from experimental research. In summary, ecologically based (which capture at-risk persons not in typical school-based samples) and more recent investigations (which have used superior or new methodologies) tend to demonstrate a linkage between music and suicidality. Experimental research is needed with a control group of songs from an alternative genre with low suicidogenic content. © 2012 The American Association of Suicidology.
Use of Internal Consistency Coefficients for Estimating Reliability of Experimental Tasks Scores
Green, Samuel B.; Yang, Yanyun; Alt, Mary; Brinkley, Shara; Gray, Shelley; Hogan, Tiffany; Cowan, Nelson
2017-01-01
Reliabilities of scores for experimental tasks are likely to differ from one study to another to the extent that the task stimuli change, the number of trials varies, the type of individuals taking the task changes, the administration conditions are altered, or the focal task variable differs. Given reliabilities vary as a function of the design of these tasks and the characteristics of the individuals taking them, making inferences about the reliability of scores in an ongoing study based on reliability estimates from prior studies is precarious. Thus, it would be advantageous to estimate reliability based on data from the ongoing study. We argue that internal consistency estimates of reliability are underutilized for experimental task data and in many applications could provide this information using a single administration of a task. We discuss different methods for computing internal consistency estimates with a generalized coefficient alpha and the conditions under which these estimates are accurate. We illustrate use of these coefficients using data for three different tasks. PMID:26546100
NASA Astrophysics Data System (ADS)
Xiao, Deli; Zhang, Chan; He, Jia; Zeng, Rong; Chen, Rong; He, Hua
2016-12-01
Simple, accurate and high-throughput pretreatment method would facilitate large-scale studies of trace analysis in complex samples. Magnetic mixed hemimicelles solid-phase extraction has the power to become a key pretreatment method in biological, environmental and clinical research. However, lacking of experimental predictability and unsharpness of extraction mechanism limit the development of this promising method. Herein, this work tries to establish theoretical-based experimental designs for extraction of trace analytes from complex samples using magnetic mixed hemimicelles solid-phase extraction. We selected three categories and six sub-types of compounds for systematic comparative study of extraction mechanism, and comprehensively illustrated the roles of different force (hydrophobic interaction, π-π stacking interactions, hydrogen-bonding interaction, electrostatic interaction) for the first time. What’s more, the application guidelines for supporting materials, surfactants and sample matrix were also summarized. The extraction mechanism and platform established in the study render its future promising for foreseeable and efficient pretreatment under theoretical based experimental design for trace analytes from environmental, biological and clinical samples.
Discussion Based Fish Bowl Strategy in Learning Psychology
ERIC Educational Resources Information Center
Singaravelu, G.
2007-01-01
The present study investigates the learning problems in psychology at Master of Education(M.Ed.,) in Bharathiar University and finds the effectiveness of Discussion Based Fish Bowl Strategy in learning psychology. Single group Experimental method was adopted for the study. Both qualitative and quantitative approaches were adopted for this study.…
Study of combustion experiments in space
NASA Technical Reports Server (NTRS)
Berlad, A. L.; Huggett, C.; Kaufman, F.; Markstein, G. H.; Palmer, H. B.; Yang, C. H.
1974-01-01
The physical bases and scientific merits were examined of combustion experimentation in a space environment. For a very broad range of fundamental combustion problems, extensive and systematic experimentation at reduced gravitational levels (0 g 1) are viewed as essential to the development of needed observations and related theoretical understanding.
Learning Experimentation through Science Fairs
ERIC Educational Resources Information Center
Paul, Jürgen; Lederman, Norman G.; Groß, Jorge
2016-01-01
Experiments are essential for both doing science and learning science. The aim of the German youth science fair, "Jugend forscht," is to encourage scientific thinking and inquiry methods such as experimentation. Based on 57 interviews with participants of the competition, this study summarises students' conceptions and steps of learning…
Making Controlled Experimentation More Informative in Inquiry Investigations
ERIC Educational Resources Information Center
McElhaney, Kevin Wei Hong
2010-01-01
This dissertation incorporates three studies that examine how the design of inquiry based science instruction, dynamic visualizations, and guidance for experimentation contribute to physics students' understanding of science. I designed a week-long, technology-enhanced inquiry module on car collisions that logs students' interactions with a…
Evaluation and experimentation with duck management strategies
Nichols, J.D.; Johnson, F.A.
1989-01-01
Our knowledge of the effects of hunting regulations on duck populations has been based largely on retrospective studies of historical data. We have reached the limits of what can be learned in this way. Future knowledge gains will likely come about only through experimentation and adaptive management.
NASA Astrophysics Data System (ADS)
Zhang, Junwei; Hong, Xuezhi; Liu, Jie; Guo, Changjian
2018-04-01
In this work, we investigate and experimentally demonstrate an orthogonal frequency division multiplexing (OFDM) based high speed wavelength-division multiplexed (WDM) visible light communication (VLC) system using an inter-block data precoding and superimposed pilots (DP-SP) based channel estimation (CE) scheme. The residual signal-to-pilot interference (SPI) can be eliminated by using inter-block data precoding, resulting in a significant improvement in estimated accuracy and the overall system performance compared with uncoded SP based CE scheme. We also study the power allocation/overhead problem of the training for DP-SP, uncoded SP and conventional preamble based CE schemes, from which we obtain the optimum signal-to-pilot power ratio (SPR)/overhead percentage for all above cases. Intra-symbol frequency-domain averaging (ISFA) is also adopted to further enhance the accuracy of CE. By using the DP-SP based CE scheme, aggregate data rates of 1.87-Gbit/s and 1.57-Gbit/s are experimentally demonstrated over 0.8-m and 2-m indoor free space transmission, respectively, using a commercially available red, green and blue (RGB) light emitting diode (LED) with WDM. Experimental results show that the DP-SP based CE scheme is comparable to the conventional preamble based CE scheme in term of received Q factor and data rate while entailing a much smaller overhead-size.
Effectiveness of breastfeeding education on the weight of child and self-efficacy of mothers – 2011
Kamran, Aziz; Shrifirad, Gholamreza; Mirkarimi, Seyed Kamal; Farahani, Abbas
2012-01-01
Background: Breastfeeding is the most natural and essential way for feeding newborn babies. This is an ideal approach for physical and emotional development of babies, as well as for the recovery of mothers. This study was aimed to determine the effect of breastfeeding education based on the health belief model (HBM) toward primiparous women. Materials and Methods: In a case–control group, quasi-experimental study, 88 subjects were allocated in control and experimental groups. Subjects who were assigned to the experimental group were provided a program consisting of group education based on HBM during their prenatal period. Instrument for data gathering was made by the researchers and standard questionnaire from Dennis and Faux for Breastfeeding Self-efficacy Scale (BSES). Baseline interviews were conducted before delivery and follow-up visits were conducted after 30 days and at the fourth month after delivery. Data were analyzed using SPSS (version 16) with c2, independent sample t-tests, and paired t-test. Results: Mean age of pregnant women who participated in the study was 22 ± 3.29 years. After the program, the experimental group had significantly better scores in terms of self-efficacy, knowledge, and attitude scores statistically. In the fourth month, the mean of child weight in the experimental group was significantly higher than that of the control group (P=0.001) and exclusive breastfeeding was significantly higher than in the control group (P=0.007). Conclusion: Prenatal education in this study based on HBM was successful, and knowledge, attitude, self-efficacy, and related indicators improved. The necessity of producing standard education package and education of pregnant mothers, especially in their first pregnancy, by health professionals is perceived. PMID:23555114
Lim, Eunjung; Mbowe, Omar; Lee, Angela S. W.; Davis, James
2016-01-01
Background Assessment of the health effects of low-level exposure to hydrogen sulfide (H2S) on humans through experiments, industrial, and community studies has shown inconsistent results. Objective To critically appraise available studies investigating the effect of H2S on the central nervous system (CNS) and on respiratory function. Methods A search was conducted in 16 databases for articles published between January 1980 and July 2014. Two researchers independently evaluated potentially relevant papers based on a set of inclusion/exclusion criteria. Results Twenty-seven articles met the inclusion criteria: 6 experimental, 12 industry-based studies, and 10 community-based studies (one article included both experimental and industry-based studies). The results of the systematic review varied by study setting and quality. Several community-based studies reported associations between day-to-day variations in H2S levels and health outcomes among patients with chronic respiratory conditions. However, evidence from the largest and better-designed community-based studies did not support that chronic, ambient H2S exposure has health effects on the CNS or respiratory function. Results from industry-based studies varied, reflecting the diversity of settings and the broad range of H2S exposures. Most studies did not have individual measurements of H2S exposure. Discussion The results across studies were inconsistent, justifying the need for further research. PMID:27128692
Lim, Eunjung; Mbowe, Omar; Lee, Angela S W; Davis, James
2016-01-01
Assessment of the health effects of low-level exposure to hydrogen sulfide (H2S) on humans through experiments, industrial, and community studies has shown inconsistent results. To critically appraise available studies investigating the effect of H2S on the central nervous system (CNS) and on respiratory function. A search was conducted in 16 databases for articles published between January 1980 and July 2014. Two researchers independently evaluated potentially relevant papers based on a set of inclusion/exclusion criteria. Twenty-seven articles met the inclusion criteria: 6 experimental, 12 industry-based studies, and 10 community-based studies (one article included both experimental and industry-based studies). The results of the systematic review varied by study setting and quality. Several community-based studies reported associations between day-to-day variations in H2S levels and health outcomes among patients with chronic respiratory conditions. However, evidence from the largest and better-designed community-based studies did not support that chronic, ambient H2S exposure has health effects on the CNS or respiratory function. Results from industry-based studies varied, reflecting the diversity of settings and the broad range of H2S exposures. Most studies did not have individual measurements of H2S exposure. The results across studies were inconsistent, justifying the need for further research.
NASA Astrophysics Data System (ADS)
Radiyonoa, Y.; Surantoro, S.; Pujayanto, P.; Budiharti, R.; Respati, Y. S.; Saputro, D. E.
2018-05-01
The occurrence of the broken pencil shadow into a glass of water becomes an interesting matter to be learned. The students of senior high school still find difficulty in determining liquid refractive index. To overcome this problem, it needs to develop an experimental tool to determine liquid refractive index by utilizing the newest technology. It is expected to be useful for students. This study is aimed to (1) make the design of physics learning experimental tool determinant of a liquid refractive index assisted by microcontroller based on ultrasonic sensors ATMega328 (2) explain the working principle and experimental result of liquid refractive indexing instrument assisted with ATMega328 microcontroller based ultrasonic sensor. This research used the experimental method. The result of the research shows design of physics learning experimental tool determinant of a liquid refractive index assisted by microcontroller based on ultrasonic sensors ATMega328 that has relative counting mistake of 0.36% on the measurement of aquades liquid refractive index, relative mistake of 0.18% on the 5% NaCl measurement, 0.24% on 5% glucose, and relative mistake of 0.50% on the measurement of 5 % fructose liquid refractive index. It has been created a proper device to be used in determining liquid refractive index.
Carey, Rachel N.; McDermott, Daragh T.; Sarma, Kiran M.
2013-01-01
The existing empirical research exploring the impact of threat appeals on driver behavior has reported inconsistent findings. In an effort to provide an up-to-date synthesis of the experimental findings, meta-analytic techniques were employed to examine the impact of threat-based messages on fear arousal and on lab-based indices of driving behavior. Experimental studies (k = 13, N = 3044), conducted between 1990 and 2011, were included in the analyses. The aims of the current analysis were (a) to examine whether or not the experimental manipulations had a significant impact on evoked fear, (b) to examine the impact of threat appeals on three distinct indices of driving, and (c) to identify moderators and mediators of the relationship between fear and driving outcomes. Large effects emerged for the level of fear evoked, with experimental groups reporting increased fear arousal in comparison to control groups (r = .64, n = 619, p<.01). The effect of threat appeals on driving outcomes, however, was not significant (r = .03, p = .17). This analysis of the experimental literature indicates that threat appeals can lead to increased fear arousal, but do not appear to have the desired impact on driving behavior. We discuss these findings in the context of threat-based road safety campaigns and future directions for experimental research in this area. PMID:23690955
Carey, Rachel N; McDermott, Daragh T; Sarma, Kiran M
2013-01-01
The existing empirical research exploring the impact of threat appeals on driver behavior has reported inconsistent findings. In an effort to provide an up-to-date synthesis of the experimental findings, meta-analytic techniques were employed to examine the impact of threat-based messages on fear arousal and on lab-based indices of driving behavior. Experimental studies (k = 13, N = 3044), conducted between 1990 and 2011, were included in the analyses. The aims of the current analysis were (a) to examine whether or not the experimental manipulations had a significant impact on evoked fear, (b) to examine the impact of threat appeals on three distinct indices of driving, and (c) to identify moderators and mediators of the relationship between fear and driving outcomes. Large effects emerged for the level of fear evoked, with experimental groups reporting increased fear arousal in comparison to control groups (r = .64, n = 619, p<.01). The effect of threat appeals on driving outcomes, however, was not significant (r = .03, p = .17). This analysis of the experimental literature indicates that threat appeals can lead to increased fear arousal, but do not appear to have the desired impact on driving behavior. We discuss these findings in the context of threat-based road safety campaigns and future directions for experimental research in this area.
Development of novel therapies for MG: Studies in animal models.
Souroujon, M C; Brenner, T; Fuchs, S
2010-08-01
Experimental myasthenia gravis (MG) in animals, and in particular experimental autoimmune MG in rodents, serves as excellent models to study possible novel therapeutic modalities for MG. The current treatments for MG are based on cholinesterase inhibitors, general immunosuppressants, and corticosteroids, broad immunomodulatory therapies such as plasma exchange or intravenous immunoglobulins (IVIGs), and thymectomy for selected patients. This stresses the need for immunotherapies that would specifically or preferentially suppress the undesirable autoimmune response without widely affecting the entire immune system as most available treatments do. The available animal models for MG enable to perform preclinical studies in which novel therapeutic approaches can be tested. In this review, we describe the different therapeutic approaches that were so far tested in experimental models of MG and discuss their underlying mechanisms of action. These include antigen - acetylcholine receptor (AChR)-dependent treatments aimed at specifically abrogating the humoral and cellular anti-AChR responses as well as immunomodulatory approaches that could be used either alone or in conjunction with antigen-specific treatments or alternatively serve as steroid sparing agents. The antigen-specific treatments are based on fragments or peptides derived from the acetylcholine receptor (AChR) that would theoretically deviate the anti-AChR autoimmune response away from the muscle target or on ways to target AChR-specific T- and B- cell responses or antibodies. The immunomodulatory modalities include cell-based and non-cell-based ways to affect or manipulate key players in the autoimmune process such as regulatory T cells, dendritic cells, cytokine networks, and chemokine and costimulatory signaling as well as complement pathways. We also describe approaches that attempt to affect the cholinergic balance, which is impaired at the neuromuscular junction. In addition to enabling to test the feasibility of novel approaches, experimental MG enables to perform analyses of existing treatment modalities, which cannot be performed in human MG patients. These include studies on the mode of action of various immunosuppressants and on IVIGs. Hopefully, the vast repertoire of therapeutic approaches that are studied in experimental models of MG will pave the way to clinical studies that will eventually improve the management of MG.
NASA Astrophysics Data System (ADS)
Dudin, S. M.; Novitskiy, D. V.
2018-05-01
The works of researchers at VNIIgaz, Giprovostokneft, Kuibyshev NIINP, Grozny Petroleum Institute, etc., are devoted to modeling heterogeneous medium flows in pipelines under laboratory conditions. In objective consideration, the empirical relationships obtained and the calculation procedures for pipelines transporting multiphase products are a bank of experimental data on the problem of pipeline transportation of multiphase systems. Based on the analysis of the published works, the main design requirements for experimental installations designed to study the flow regimes of gas-liquid flows in pipelines were formulated, which were taken into account by the authors when creating the experimental stand. The article describes the results of experimental studies of the flow regimes of a gas-liquid mixture in a pipeline, and also gives a methodological description of the experimental installation. Also the article describes the software of the experimental scientific and educational stand developed with the participation of the authors.
Hollmann, M; Mönch, T; Mulla-Osman, S; Tempelmann, C; Stadler, J; Bernarding, J
2008-10-30
In functional MRI (fMRI) complex experiments and applications require increasingly complex parameter handling as the experimental setup usually consists of separated soft- and hardware systems. Advanced real-time applications such as neurofeedback-based training or brain computer interfaces (BCIs) may even require adaptive changes of the paradigms and experimental setup during the measurement. This would be facilitated by an automated management of the overall workflow and a control of the communication between all experimental components. We realized a concept based on an XML software framework called Experiment Description Language (EDL). All parameters relevant for real-time data acquisition, real-time fMRI (rtfMRI) statistical data analysis, stimulus presentation, and activation processing are stored in one central EDL file, and processed during the experiment. A usability study comparing the central EDL parameter management with traditional approaches showed an improvement of the complete experimental handling. Based on this concept, a feasibility study realizing a dynamic rtfMRI-based brain computer interface showed that the developed system in combination with EDL was able to reliably detect and evaluate activation patterns in real-time. The implementation of a centrally controlled communication between the subsystems involved in the rtfMRI experiments reduced potential inconsistencies, and will open new applications for adaptive BCIs.
Zhu, Yu; Zhang, Zhihong; Ling, Yun; Wan, Hongwei
2017-04-01
Breastfeeding knowledge, attitude, subjective norm, and perceived control are significant determinants of breastfeeding, according to the theory of planned behavior (TPB). However, evidence concerning the effectiveness of the TPB-based intervention in breastfeeding promotion is sparse. Meanwhile, the changes of these determinants with time have not been examined in previous studies. To investigate the effectiveness of the TPB-based intervention program in improving exclusive breastfeeding, and the interaction of time and intervention on these determinants of breastfeeding. 285 primiparous mothers were included, with 157 mothers in the experimental group and 128 mothers in the control group. The experimental group received the TPB-based intervention program delivered during 6 weeks postpartum, while both the experimental and control groups received the standard obstetric care. Scores of breastfeeding knowledge, attitude and breastfeeding control increased with time from baseline to 6 weeks postpartum, while breastfeeding subjective norm decreased at 6 weeks both in the experimental and the control groups. Besides, scores of the four determinants were significantly higher in the experimental group than these in the control group at 3days and 6 weeks, except for breastfeeding control at 6 weeks, which resulted in the higher exclusive breastfeeding rates at 3days and 6 weeks in the experimental group than the control group. The TPB-based intervention was effective in promoting exclusive breastfeeding during 6 weeks postpartum. Future interventions are recommended to adjust intervention strategies with time, and give more focus on providing continued breastfeeding support after discharge. Copyright © 2016 Australian College of Midwives. Published by Elsevier Ltd. All rights reserved.
Educational Intervention on Undergraduate Cancer Awareness and Self-Directed Learning.
Hwang, Lih-Lian
2018-06-01
Traditional lecture-based learning (LBL) can increase cancer awareness in undergraduates. However, because of the rapidly changing knowledge base in medicine, undergraduates must develop skills required for lifelong self-directed learning (SDL). Problem-based learning (PBL) has been suggested as an SDL approach. This study used a nonequivalent control group with a pretest-posttest design for comparing PBL and LBL for their effectiveness in increasing cancer awareness and SDL among nonmedicine or nonnursing major undergraduates in a health-related general education course. Experimental groups 1 and 2 were instructed using PBL while the control group was instructed using LBL. Cancer educational programs were offered to experimental group 1 and the control group but not to experimental group 2. Among the 325 undergraduates who completed a questionnaire regarding cancer awareness and SDL in the pretest, 223 completed the 12-week follow-up survey of the posttest. Cancer awareness significantly improved between the pretest and posttest in the control group (P < 0.001). No significant difference in cancer awareness improvement was observed between experimental group 1 and the control group (P = 0.934). Cancer awareness improvement in experimental group 2 was significantly less than in the control group (P = 0.010). No statistically significant change in SDL was observed in the control group during the study (P = 0.897). However, the SDL of experimental groups 1 and 2 improved more significantly than that of the control group (P = 0.049 and 0.023, respectively). Therefore, PBL is an effective method of increasing cancer awareness and SDL in undergraduates.
Experimental study of adaptive pointing and tracking for large flexible space structures
NASA Technical Reports Server (NTRS)
Boussalis, D.; Bayard, D. S.; Ih, C.; Wang, S. J.; Ahmed, A.
1991-01-01
This paper describes an experimental study of adaptive pointing and tracking control for flexible spacecraft conducted on a complex ground experiment facility. The algorithm used in this study is based on a multivariable direct model reference adaptive control law. Several experimental validation studies were performed earlier using this algorithm for vibration damping and robust regulation, with excellent results. The current work extends previous studies by addressing the pointing and tracking problem. As is consistent with an adaptive control framework, the plant is assumed to be poorly known to the extent that only system level knowledge of its dynamics is available. Explicit bounds on the steady-state pointing error are derived as functions of the adaptive controller design parameters. It is shown that good tracking performance can be achieved in an experimental setting by adjusting adaptive controller design weightings according to the guidelines indicated by the analytical expressions for the error.
ERIC Educational Resources Information Center
Santagata, Rossella; Kersting, Nicole; Givvin, Karen B.; Stigler, James W.
2011-01-01
This study investigates, through an experimental design, the effectiveness of a professional development program on teacher knowledge and practices and on student learning. The program consisted of a series of video-based modules designed to respond to needs of U.S. teachers, as highlighted by findings from the 1999 Third International Mathematics…
ERIC Educational Resources Information Center
Kaya, Osman Nafiz; Dogan, Alev; Gokcek, Nur; Kilic, Ziya; Kilic, Esma
2007-01-01
The purpose of this study was to investigate the effects of multiple intelligences (MI) teaching approach on 8th Grade students' achievement in and attitudes toward science. This study used a pretest-posttest control group experimental design. While the experimental group (n=30) was taught a unit on acids and bases using MI teaching approach, the…
ERIC Educational Resources Information Center
Burns, Matthew K.; Taylor, Crystal N.; Warmbold-Brann, Kristy L.; Preast, June L.; Hosp, John L.; Ford, Jeremy W.
2017-01-01
Intervention researchers often use curriculum-based measurement of reading fluency (CBM-R) with a brief experimental analysis (BEA) to identify an effective intervention for individual students. The current study synthesized data from 22 studies that used CBM-R data within a BEA by computing the standard error of measure (SEM) for the median data…
ERIC Educational Resources Information Center
AlJaser, Afaf Mohammed
2017-01-01
The present study is an attempt to measure the effectiveness of using flipped classroom strategy in academic achievement and self-efficacy among female students of College of Education, Princess Nourah bint Abdulrahman University (PNU), Saudi Arabia. The study adopted the experimental method based on the two experimental and control groups, where…
Performance evaluation of nursing students following competency-based education.
Fan, Jun-Yu; Wang, Yu Hsin; Chao, Li Fen; Jane, Sui-Whi; Hsu, Li-Ling
2015-01-01
Competency-based education is known to improve the match between educational performance and employment opportunities. This study examined the effects of competency-based education on the learning outcomes of undergraduate nursing students. The study used a quasi-experimental design. A convenience sample of 312 second-year undergraduate nursing students from northern and southern Taiwan participated in the study. The experimental group (n=163) received competency-based education and the control group received traditional instruction (n=149) in a medical-surgical nursing course. Outcome measures included students' scores on the Objective Structured Clinical Examination, Self-Evaluated Core Competencies Scale, Metacognitive Inventory for Nursing Students questionnaire, and academic performance. Students who received competency-based education had significantly higher academic performance in the medical-surgical nursing course and practicum than did the control group. Required core competencies and metacognitive abilities improved significantly in the competency-based education group as compared to the control group after adjusting for covariates. Competency-based education is worth implementing and may close the gap between education and the ever-changing work environment. Copyright © 2014 Elsevier Ltd. All rights reserved.
An electrical resistivity-based method for investigation of subsurface structure
NASA Astrophysics Data System (ADS)
Alves Meira Neto, A.; Litwin, D.; Troch, P. A. A.; Ferre, T. P. A.
2017-12-01
Resolving the spatial distribution of soil porosity within the subsurface is of great importance for understanding flow and transport within heterogeneous media. Additionally, porosity patterns can be associated with the availability of water and carbon dioxide that will drive geochemical reactions and constrain microbiological growth. The use of controlled experimentation has the potential to circumvent problems related to the external and internal variability of natural systems, while also allowing a higher degree of observability. In this study, we suggest an ERT-based method of retrieving porosity fields based on the application of Archie's law associated with an experimental procedure that can be used in laboratory-scale studies. We used a 2 cubic meter soil lysimeter, equipped with 238 electrodes distributed along its walls for testing the method. The lysimeter serves as a scaled-down version of the highly monitored artificial hillslopes at the Landscape Evolution Observatory (LEO) located at Biosphere 2 - University of Arizona. The capability of the ERT system in deriving spatially distributed patterns of porosity with respect to its several sources of uncertainty was numerically evaluated. The results will be used to produce an optimal experimental design and for assessing the reliability of experimental results. This novel approach has the potential to further resolve subsurface heterogeneity within the LEO project, and highlight the use of ERT-derived results for hydro-bio-geochemical studies.
NASA Astrophysics Data System (ADS)
Nugroho, O. F.; Chandra, D. T.; Sanjaya, Y.; Pendidikan Indonesia, Universitas
2017-02-01
The purpose of this study was to improve students’ concept comprehension using concept map as a consolidation phase based STAD. This study was conducted by randomized control group pretest-posttest. Data was collected by using an instrument test to evaluate the effect of concept map as a consolidation phase based STAD on students’understanding about environmental pollution. Data was analyzed using normalized gain (n-gain) and independent t-test. The n-gain analysis shows the increased of students’s understanding about environmental pollution at experimental group arehigher than at the control group. The result of this study showed that students’ comprehension at the experimental class (0,53) higher compared to the control group (0,23). Whilst the t-test analysis shows that there is a significant effect of mapping concept as a consolidation phase based STAD towards students’ concept comprehension. It can be concluded that the implementation of mapping concept based STAD may improve the students’s understanding on science concept.
ERIC Educational Resources Information Center
Choukas-Bradley, Sophia; Giletta, Matteo; Widman, Laura; Cohen, Geoffrey L.; Prinstein, Mitchell J.
2014-01-01
A performance-based measure of peer influence susceptibility was examined as a moderator of the longitudinal association between peer norms and trajectories of adolescents' number of sexual intercourse partners. Seventy-one 9th grade adolescents (52% female) participated in an experimental "chat room" paradigm involving…
Inquiry in the Physical Geology Classroom: Supporting Students' Conceptual Model Development
ERIC Educational Resources Information Center
Miller, Heather R.; McNeal, Karen S.; Herbert, Bruce E.
2010-01-01
This study characterizes the impact of an inquiry-based learning (IBL) module versus a traditionally structured laboratory exercise. Laboratory sections were randomized into experimental and control groups. The experimental group was taught using IBL pedagogical techniques and included manipulation of large-scale data-sets, use of multiple…
ERIC Educational Resources Information Center
Bal, Aydin; Trainor, Audrey A.
2016-01-01
Neither legislative demand for evidence-based practices nor a focus on experimental designs for educational interventions has ameliorated the disparate educational opportunities and outcomes for youth from nondominant cultural and linguistic backgrounds. Recent initiatives to increase the rigor of intervention research in special education have…
Function-Altering Effects of Rule Phrasing in the Modulation of Instructional Control
ERIC Educational Resources Information Center
Henley, Amy J.; Hirst, Jason M.; DiGennaro Reed, Florence D.; Becirevic, Amel; Reed, Derek D.
2017-01-01
This study evaluated the effects of four instructional variants on instruction following under changing reinforcement schedules using an operant task based on Hackenberg and Joker's "Journal of the Experimental Analysis of Behavior," 62, 367-383 (1994) experimental preparation. Sixteen college-aged adults served as participants and were…
Video Game-Based Methodology for Business Research
ERIC Educational Resources Information Center
Lawson, Larry L.; Lawson, Catherine L.
2010-01-01
Experimental research in business and economics has exploded in recent years in both laboratory and field settings. The generality of findings from field experiments is limited by the specificity of the experimental environment. Laboratory studies, on the other hand, are criticized for being devoid of the contextual cues that may indicate to…
Predictions of nuclear charge radii
NASA Astrophysics Data System (ADS)
Bao, M.; Lu, Y.; Zhao, Y. M.; Arima, A.
2016-12-01
The nuclear charge radius is a fundamental property of an atomic nucleus. In this article we study the predictive power of empirical relations for experimental nuclear charge radii of neighboring nuclei and predict the unknown charge radii of 1085 nuclei based on the experimental CR2013 database within an uncertainty of 0.03 fm.
Emotional Arousal of Beginning Physics Teachers during Extended Experimental Investigations
ERIC Educational Resources Information Center
Ritchie, Stephen M.; Tobin, Kenneth; Sandhu, Maryam; Sandhu, Satwant; Henderson, Senka; Roth, Wolff-Michael
2013-01-01
Teachers often have difficulty implementing inquiry-based activities, leading to the arousal of negative emotions. In this multicase study of beginning physics teachers in Australia, we were interested in the extent to which their expectations were realized and how their classroom experiences while implementing extended experimental investigations…
Valente, Marco A G; Teixeira, Deiver A; Azevedo, David L; Feliciano, Gustavo T; Benedetti, Assis V; Fugivara, Cecílio S
2017-01-01
The interaction of volatile corrosion inhibitors (VCI), caprylate salt derivatives from amines, with zinc metallic surfaces is assessed by density functional theory (DFT) computer simulations, electrochemical impedance (EIS) measurements and humid chamber tests. The results obtained by the different methods were compared, and linear correlations were obtained between theoretical and experimental data. The correlations between experimental and theoretical results showed that the molecular size is the determining factor in the inhibition efficiency. The models used and experimental results indicated that dicyclohexylamine caprylate is the most efficient inhibitor.
Laboratory Based Case Studies: Closer to the Real World
ERIC Educational Resources Information Center
Dinan, Frank J.
2005-01-01
Case-based laboratories offer students the chance to approximate real science. Based on interesting stories that pose problems requiring experimental solutions, they avoid the cookbook approach characteristic of traditional undergraduate laboratory instruction. Instead, case-based laboratories challenge students to develop, as much as possible,…
ERIC Educational Resources Information Center
Paska, Lawrence M.
2010-01-01
This quasi-experimental study uses mixed methodologies to examine learning engagement on a social studies unit test based on primary and secondary sources (a "document-based question", or DBQ), to determine whether the use of film in a DBQ changes the nature of historical inquiry. The study was conducted in two Grade 7 classes taught by the same…
Gamma Prime Precipitate Evolution During Aging of a Model Nickel-Based Superalloy
NASA Astrophysics Data System (ADS)
Goodfellow, A. J.; Galindo-Nava, E. I.; Christofidou, K. A.; Jones, N. G.; Martin, T.; Bagot, P. A. J.; Boyer, C. D.; Hardy, M. C.; Stone, H. J.
2018-03-01
The microstructural stability of nickel-based superalloys is critical for maintaining alloy performance during service in gas turbine engines. In this study, the precipitate evolution in a model polycrystalline Ni-based superalloy during aging to 1000 hours has been studied via transmission electron microscopy, atom probe tomography, and neutron diffraction. Variations in phase composition and precipitate morphology, size, and volume fraction were observed during aging, while the constrained lattice misfit remained constant at approximately zero. The experimental composition of the γ matrix phase was consistent with thermodynamic equilibrium predictions, while significant differences were identified between the experimental and predicted results from the γ' phase. These results have implications for the evolution of mechanical properties in service and their prediction using modeling methods.
NASA Astrophysics Data System (ADS)
Tsaturyan, Arshak; Machida, Yosuke; Akitsu, Takashiro; Gozhikova, Inna; Shcherbakov, Igor
2018-06-01
We report on synthesis and characterization of binaphthyl containing Schiff base Ni(II), Cu(II), and Zn(II) complexes as promising photosensitizers for dye-sensitized solar cells (DSSC). Based on theoretical and experimental data, the possibility of their application in DSSC was confirmed. To our knowledge, we find dye performance of complex is steric and rigid structure widely spread to efficiency. The spatial and electronic structures of the complexes were studied by means of the quantum chemical modeling using DFT and TD-DFT approaches. The adsorption energies of the complexes on TiO2 cluster were calculated and appeared to be very close in value. The Zn(II) complex has the biggest value of molar extinction.
Principles and performance of tapered fiber lasers: from uniform to flared geometry.
Kerttula, Juho; Filippov, Valery; Chamorovskii, Yuri; Ustimchik, Vasily; Golant, Konstantin; Okhotnikov, Oleg G
2012-10-10
We have studied the recently demonstrated concept of fiber lasers based on active tapered double-clad fiber (T-DCF) in copropagating and counterpropagating configurations, both theoretically and experimentally, and compared the performance to fiber lasers based on conventional cylindrical fibers in end-pumped configurations. Specific properties of T-DCFs were considered theoretically using a rate-equation model developed for tapered fibers, and a detailed comparative study was carried out experimentally. Furthermore, we have studied mode coupling effects in long adiabatic tapers due to coiling and local bending. The results allow us to conclude that, with proper fiber design, the T-DCF technology offers a high-potential alternative for bright, cost-effective fiber devices.
SAW based micro- and acousto-fluidics in biomedicine
NASA Astrophysics Data System (ADS)
Ramasamy, Mouli; Varadan, Vijay K.
2017-04-01
Protein association starts with random collisions of individual proteins. Multiple collisions and rotational diffusion brings the molecules to a state of orientation. Majority of the protein associations are influenced by electrostatic interactions. To introduce: electrostatic rate enhancement, Brownian dynamics and transient complex theory has been traditionally used. Due to the recent advances in interdisciplinary sciences, an array of molecular assembly methods is being studied. Protein nanostructural assembly and macromolecular crowding are derived from the subsets of biochemistry to study protein-protein interactions and protein self-assembly. This paper tries to investigate the issue of enhancing the protein self-association rate, and bridging the gap between the simulations and experimental results. The methods proposed here include: electrostatic rate enhancement, macromolecular crowing, nanostructural protein assembly, microfluidics based approaches and magnetic force based approaches. Despite the suggestions of several methods, microfluidic and magnetic force based approaches seem to serve the need of protein assembly in a wider scale. Congruence of these approaches may also yield better results. Even though, these methods prove to be conceptually strong, to prevent the disagreement of theory and practice, a wide range of experiments is required. This proposal intends to study theoretical and experimental methods to successfully implement the aforementioned assembly strategies, and conclude with an extensive analysis of experimental data to address practical feasibility.
Dean Stull
2016-05-24
Experimental results from several studies exploring the impact of pH and acid volume on the stripping of rare earth elements (REEs) loaded onto ligand-based media via an active column. The REEs in this experiment were loaded onto the media through exposure to a simulated geothermal brine with known mineral concentrations. The data include the experiment results, rare earth element concentrations, and the experimental parameters varied.
2011-12-01
determine laminar flame speeds using the spherical flame method. An experimental combustion chamber, based on the constant-volume bomb method, was...INTENTIONALLY LEFT BLANK v ABSTRACT This thesis presents the results of an experimental study to determine laminar flame speeds using the spherical...for ethane/air flames at various pressures reproduced from [6]....................8 Figure 4. Experimentally determined laminar flame speed as a
The Impact of Web-Based Assessment and Practice on Students' Mathematics Learning Attitudes
ERIC Educational Resources Information Center
Nguyen, Diem M.; Hsieh, Yi-Chuan; Allen, G. Donald
2006-01-01
This study investigates the effects of web-based assessment and practice on improving middle school students' mathematics learning attitudes. With the use of an experimental design and a combination of quantitative and qualitative methods, the study compared and contrasted the attitude achievement of students, who used the web-based assessment and…
ERIC Educational Resources Information Center
Tsai, Chia-Hui; Cheng, Ching-Hsue; Yeh, Duen-Yian; Lin, Shih-Yun
2017-01-01
This study applied a quasi-experimental design to investigate the influence and predictive power of learner motivation for achievement, employing a mobile game-based English learning approach. A system called the Happy English Learning System, integrating learning material into a game-based context, was constructed and installed on mobile devices…
ERIC Educational Resources Information Center
Hwang, Wu-Yuin; Shih, Timothy K.; Ma, Zhao-Heng; Shadiev, Rustam; Chen, Shu-Yu
2016-01-01
Game-based learning activities that facilitate students' listening and speaking skills were designed in this study. To participate in learning activities, students in the control group used traditional methods, while students in the experimental group used a mobile system. In our study, we looked into the feasibility of mobile game-based learning…
Problem-Based Learning in K-8 Mathematics and Science Education: A Literature Review
ERIC Educational Resources Information Center
Merritt, Joi; Lee, Mi Yeon; Rillero, Peter; Kinach, Barbara M.
2017-01-01
This systematic literature review was conducted to explore the effectiveness of problem-based and project-based learning (PBL) implemented with students in early elementary to grade 8 (ages 3-14) in mathematics and science classrooms. Nine studies met the following inclusion criteria: (a) focus on PBL, (b) experimental study, (c) kindergarten to…
ERIC Educational Resources Information Center
Kurtulus, Aytac
2013-01-01
The aim of this study was to investigate the effects of web-based interactive virtual tours on the development of prospective mathematics teachers' spatial skills. The study was designed based on experimental method. The "one-group pre-test post-test design" of this method was taken as the research model. The study was conducted with 3rd year…
Degrazia, Felipe Weidenbach; Leitune, Vicente Castelo Branco; Takimi, Antonio Shigueaki; Collares, Fabrício Mezzomo; Sauro, Salvatore
2016-09-01
This study aimed to assess the degree of conversion, microhardness, solvent degradation, contact angle, surface free energy and bioactivity (e.g., mineral precipitation) of experimental resin-based materials containing, pure or triclosan-encapsulated, aluminosilicate-(halloysite) nanotubes. An experimental resin blend was prepared using bis-GMA/TEGDMA, 75/25wt% (control). Halloysite nanotubes (HNT) doped with or without triclosan (TCN) were first analyzed using transmission electron microscopy (TEM). HNT or HNT/TCN fillers were incorporated into the resin blend at different concentrations (5, 10, and 20wt%). Seven experimental resins were created and the degree of conversion, microhardness, solvent degradation and contact angle were assessed. Bioactive mineral precipitation induced by the experimental resins was evaluated through Raman spectroscopy and SEM-EDX. TEM showed a clear presence of TCN particles inside the tubular lumen and along the outer surfaces of the halloysite nanotubes. The degree of conversion, surface free energy, microhardness, and mineral deposition of polymers increased with higher amount of HNTs. Conversely, the higher the amount (20wt%) of TCN-loaded HNTs the lower the microhardness of the experimental resins. The incorporation of pure or TCN-loaded aluminosilicate-(halloysite) nanotubes into resin-based materials increase the bioactivity of such experimental restorative materials and promotes mineral deposition. Therefore, innovative resin-based materials containing functional halloysite-nanotube fillers may represent a valuable alternative for therapeutic minimally invasive treatments. Copyright © 2016 The Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.
Fischer, Kenneth J; Johnson, Joshua E; Waller, Alexander J; McIff, Terence E; Toby, E Bruce; Bilgen, Mehmet
2011-10-01
The objective of this study was to validate the MRI-based joint contact modeling methodology in the radiocarpal joints by comparison of model results with invasive specimen-specific radiocarpal contact measurements from four cadaver experiments. We used a single validation criterion for multiple outcome measures to characterize the utility and overall validity of the modeling approach. For each experiment, a Pressurex film and a Tekscan sensor were sequentially placed into the radiocarpal joints during simulated grasp. Computer models were constructed based on MRI visualization of the cadaver specimens without load. Images were also acquired during the loaded configuration used with the direct experimental measurements. Geometric surface models of the radius, scaphoid and lunate (including cartilage) were constructed from the images acquired without the load. The carpal bone motions from the unloaded state to the loaded state were determined using a series of 3D image registrations. Cartilage thickness was assumed uniform at 1.0 mm with an effective compressive modulus of 4 MPa. Validation was based on experimental versus model contact area, contact force, average contact pressure and peak contact pressure for the radioscaphoid and radiolunate articulations. Contact area was also measured directly from images acquired under load and compared to the experimental and model data. Qualitatively, there was good correspondence between the MRI-based model data and experimental data, with consistent relative size, shape and location of radioscaphoid and radiolunate contact regions. Quantitative data from the model generally compared well with the experimental data for all specimens. Contact area from the MRI-based model was very similar to the contact area measured directly from the images. For all outcome measures except average and peak pressures, at least two specimen models met the validation criteria with respect to experimental measurements for both articulations. Only the model for one specimen met the validation criteria for average and peak pressure of both articulations; however the experimental measures for peak pressure also exhibited high variability. MRI-based modeling can reliably be used for evaluating the contact area and contact force with similar confidence as in currently available experimental techniques. Average contact pressure, and peak contact pressure were more variable from all measurement techniques, and these measures from MRI-based modeling should be used with some caution.
Moreira, Paulo; Crusellas, Lorena; Sá, Isabel; Gomes, Paulo; Matias, Carla
2010-09-01
The promotion of socio-emotional skills in educational contexts is highly beneficial to individuals' global adjustment and development. Evaluation research suggests that interventions for the promotion of socio-emotional skills are effective. However, most of this work has been carried out in the USA and there is now a pressing need to evaluate interventions at the cross-cultural level. This 4-year study evaluated the effectiveness of a teacher manual-based intervention for the promotion of social and emotional skills in Portuguese elementary school children. Using a quasi-experimental design, teachers taught manual-based strategies to children in the experimental group, focusing on specific social and emotional skills. These strategies were integrated as part of the curricular activities. Results showed statistically significant differences between the experimental group and the control group on the evaluated outcomes (self-control, emotional differentiation, emotional regulation, social skills, and self-esteem). For each of the dimensions studied, effect sizes were large (above 0.80). Findings are similar to those reported by international research evaluating the effectiveness of programmes for the promotion of social and emotional skills in school-age children. This study is an important contribution in the establishment of evidence-based socio-emotional skills programmes at the cross-cultural level.
ERIC Educational Resources Information Center
Kvavilashvili, Lia; Fisher, Laura
2007-01-01
The present research examined self-reported rehearsal processes in naturalistic time-based prospective memory tasks (Study 1 and 2) and compared them with the processes in event-based tasks (Study 3). Participants had to remember to phone the experimenter either at a prearranged time (a time-based task) or after receiving a certain text message…
Task-Based Language Teaching for Beginner-Level Learners of L2 French: An Exploratory Study
ERIC Educational Resources Information Center
Erlam, Rosemary; Ellis, Rod
2018-01-01
This study investigated the effect of input-based tasks on the acquisition of vocabulary and grammar by beginner-level learners of L2 French and reported the introduction of task-based teaching as an innovation in a state secondary school. The experimental group (n = 19) completed a series of focused input-based language tasks, taught by their…
ERIC Educational Resources Information Center
Karatas, Sercin; Simsek, Nurettin
2009-01-01
The purpose of this study is to determine whether "equivalent learning experiences" ensure equivalency, in the Internet-based and face-to-face interaction methods on learning results and student satisfaction. In the experimental process of this study, the effect of the Internet-based and face-to-face learning on the equivalency in…
Zakarienė, Gintarė; Rokaitytė, Anita; Ramonaitė, Sigita; Novoslavskij, Aleksandr; Mulkytė, Kristina; Zaborskienė, Gintarė; Malakauskas, Mindaugas
2015-03-01
The antimicrobial effect of spice-based marinades against Campylobacter jejuni on inoculated fresh broiler wings was investigated. Experiments were carried out with 1 strain of C. jejuni and 6 marinades. Four experimental marinades were composed for the study and contained spices (thyme, rosemary, basil, marjoram, and so on) and different combination of bioactive compounds. Two marinades were commercial and contained spices (black pepper, sweet red pepper, and so on) and chemical additives (monosodium glutamate, sodium diacetate, calcium lactate), 1 commercial marinade was also enriched with bioactive compounds (linalool, cinnamaldehyde, lactic acid). Total aerobic bacterial count was examined to estimate the possible effect of tested marinades on the shelf-life of marinated broiler wings. Study revealed that thyme-based marinade was the most effective against C. jejuni on broiler wings and reduced the numbers of campylobacters by 1.04 log colony forming unit (CFU)/g (P ≤ 0.05) during storage for 168 h at 4 °C temperature. Moreover, it was more effective against C. jejuni than commercial marinade with 0.47 log CFU/g (P ≤ 0.05) reduction effect. Both experimental and commercial marinades had very similar effect on the total aerobic bacterial count. Although experimental and commercial marinades had different effect on pH of broiler wings, this parameter did not show a major impact on the antimicrobial effect of tested marinades (P ≥ 0.05). Our study shows that experimental natural thyme-based marinade can reduce numbers of C. jejuni more effectively than tested commercial marinades. © 2015 Institute of Food Technologists®
Experimental and AI-based numerical modeling of contaminant transport in porous media.
Nourani, Vahid; Mousavi, Shahram; Sadikoglu, Fahreddin; Singh, Vijay P
2017-10-01
This study developed a new hybrid artificial intelligence (AI)-meshless approach for modeling contaminant transport in porous media. The key innovation of the proposed approach is that both black box and physically-based models are combined for modeling contaminant transport. The effectiveness of the approach was evaluated using experimental and real world data. Artificial neural network (ANN) and adaptive neuro-fuzzy inference system (ANFIS) were calibrated to predict temporal contaminant concentrations (CCs), and the effect of noisy and de-noised data on the model performance was evaluated. Then, considering the predicted CCs at test points (TPs, in experimental study) and piezometers (in Myandoab plain) as interior conditions, the multiquadric radial basis function (MQ-RBF), as a meshless approach which solves partial differential equation (PDE) of contaminant transport in porous media, was employed to estimate the CC values at any point within the study area where there was no TP or piezometer. Optimal values of the dispersion coefficient in the advection-dispersion PDE and shape coefficient of MQ-RBF were determined using the imperialist competitive algorithm. In temporal contaminant transport modeling, de-noised data enhanced the performance of ANN and ANFIS methods in terms of the determination coefficient, up to 6 and 5%, respectively, in the experimental study and up to 39 and 18%, respectively, in the field study. Results showed that the efficiency of ANFIS-meshless model was more than ANN-meshless model up to 2 and 13% in the experimental and field studies, respectively. Copyright © 2017. Published by Elsevier B.V.
Wong, Lai Fun; Chan, Sally Wai-Chi; Ho, Jasmine Tze Yin; Mordiffi, Siti Zubaidah; Ang, Sophia Bee Leng; Goh, Poh Sun; Ang, Emily Neo Kim
2015-01-01
Background Web-based learning is becoming an increasingly important instructional tool in nursing education. Multimedia advancements offer the potential for creating authentic nursing activities for developing nursing competency in clinical practice. Objective This study aims to describe the design, development, and evaluation of an interactive multimedia Web-based simulation for developing nurses’ competencies in acute nursing care. Methods Authentic nursing activities were developed in a Web-based simulation using a variety of instructional strategies including animation video, multimedia instructional material, virtual patients, and online quizzes. A randomized controlled study was conducted on 67 registered nurses who were recruited from the general ward units of an acute care tertiary hospital. Following a baseline evaluation of all participants’ clinical performance in a simulated clinical setting, the experimental group received 3 hours of Web-based simulation and completed a survey to evaluate their perceptions of the program. All participants were re-tested for their clinical performances using a validated tool. Results The clinical performance posttest scores of the experimental group improved significantly (P<.001) from the pretest scores after the Web-based simulation. In addition, compared to the control group, the experimental group had significantly higher clinical performance posttest scores (P<.001) after controlling the pretest scores. The participants from the experimental group were satisfied with their learning experience and gave positive ratings for the quality of the Web-based simulation. Themes emerging from the comments about the most valuable aspects of the Web-based simulation include relevance to practice, instructional strategies, and fostering problem solving. Conclusions Engaging in authentic nursing activities using interactive multimedia Web-based simulation can enhance nurses’ competencies in acute care. Web-based simulations provide a promising educational tool in institutions where large groups of nurses need to be trained in acute nursing care and accessibility to repetitive training is essential for achieving long-term retention of clinical competency. PMID:25583029
Liaw, Sok Ying; Wong, Lai Fun; Chan, Sally Wai-Chi; Ho, Jasmine Tze Yin; Mordiffi, Siti Zubaidah; Ang, Sophia Bee Leng; Goh, Poh Sun; Ang, Emily Neo Kim
2015-01-12
Web-based learning is becoming an increasingly important instructional tool in nursing education. Multimedia advancements offer the potential for creating authentic nursing activities for developing nursing competency in clinical practice. This study aims to describe the design, development, and evaluation of an interactive multimedia Web-based simulation for developing nurses' competencies in acute nursing care. Authentic nursing activities were developed in a Web-based simulation using a variety of instructional strategies including animation video, multimedia instructional material, virtual patients, and online quizzes. A randomized controlled study was conducted on 67 registered nurses who were recruited from the general ward units of an acute care tertiary hospital. Following a baseline evaluation of all participants' clinical performance in a simulated clinical setting, the experimental group received 3 hours of Web-based simulation and completed a survey to evaluate their perceptions of the program. All participants were re-tested for their clinical performances using a validated tool. The clinical performance posttest scores of the experimental group improved significantly (P<.001) from the pretest scores after the Web-based simulation. In addition, compared to the control group, the experimental group had significantly higher clinical performance posttest scores (P<.001) after controlling the pretest scores. The participants from the experimental group were satisfied with their learning experience and gave positive ratings for the quality of the Web-based simulation. Themes emerging from the comments about the most valuable aspects of the Web-based simulation include relevance to practice, instructional strategies, and fostering problem solving. Engaging in authentic nursing activities using interactive multimedia Web-based simulation can enhance nurses' competencies in acute care. Web-based simulations provide a promising educational tool in institutions where large groups of nurses need to be trained in acute nursing care and accessibility to repetitive training is essential for achieving long-term retention of clinical competency.
A Vibration-Based Strategy for Health Monitoring of Offshore Pipelines' Girth-Welds
Razi, Pejman; Taheri, Farid
2014-01-01
This study presents numerical simulations and experimental verification of a vibration-based damage detection technique. Health monitoring of a submerged pipe's girth-weld against an advancing notch is attempted. Piezoelectric transducers are bonded on the pipe for sensing or actuation purposes. Vibration of the pipe is excited by two means: (i) an impulsive force; (ii) using one of the piezoelectric transducers as an actuator to propagate chirp waves into the pipe. The methodology adopts the empirical mode decomposition (EMD), which processes vibration data to establish energy-based damage indices. The results obtained from both the numerical and experimental studies confirm the integrity of the approach in identifying the existence, and progression of the advancing notch. The study also discusses and compares the performance of the two vibration excitation means in damage detection. PMID:25225877
ERIC Educational Resources Information Center
Alias, Norlidah; Siraj, Saedah; Daud, Mohd Khairul Azman Md; Hussin, Zaharah
2013-01-01
The study examines the effectiveness of Facebook based learning to enhance creativity among Islamic Studies students in the secondary educational setting in Malaysia. It describes the design process by employing the Isman Instructional Design Model. A quantitative study was carried out using experimental method and background survey. The…
Effect of web-based education on nursing students' urinary catheterization knowledge and skills.
Öztürk, Deniz; Dinç, Leyla
2014-05-01
Nursing is a practice-based discipline that requires the integration of theory and practice. Nurse educators must continuously revise educational curricula and incorporate information technology into the curriculum to provide students with the necessary knowledge and skills. The aim of this study was to assess the effect of web-based education on students' urinary catheterization knowledge and skills. A convenience sample of 111 first year nursing students enrolled at two universities in Ankara during the academic year of 2011-2012 participated in this quasi-experimental study. The experimental group (n=59) received a web-based and web-enhanced learning approach along with learning and practicing the required material twice as much as the control group, whereas the control group (n=52) received traditional classroom instruction. A knowledge test of 20 multiple-choice questions and a skills checklist were used to assess student performance. There was no difference between the experimental group and the control group in knowledge scores; however, students in the web-based group had higher scores for urinary catheterization skills. The highest scores in knowledge and skills were obtained by students who experienced web-based education as a supplement to tradition instruction. Web-based education had positive effects on the urinary catheterization skills of nursing students, and its positive effect increased for both knowledge and skills when it supplements classroom instruction. Based on these results, we suggest the use of web-based education as a supplement to traditional classroom instruction for nursing education. © 2013.
Investigation of effective strategies for developing creative science thinking
NASA Astrophysics Data System (ADS)
Yang, Kuay-Keng; Lee, Ling; Hong, Zuway-R.; Lin, Huann-shyang
2016-09-01
The purpose of this study was to explore the effectiveness of the creative inquiry-based science teaching on students' creative science thinking and science inquiry performance. A quasi-experimental design consisting one experimental group (N = 20) and one comparison group (N = 24) with pretest and post-test was conducted. The framework of the intervention focused on potential strategies such as promoting divergent and convergent thinking and providing an open, inquiry-based learning environment that are recommended by the literature. Results revealed that the experimental group students outperformed their counterparts in the comparison group on the performances of science inquiry and convergent thinking. Additional qualitative data analyses from classroom observations and case teacher interviews identified supportive teaching strategies (e.g. facilitating associative thinking, sharing impressive ideas, encouraging evidence-based conclusions, and reviewing and commenting on group presentations) for developing students' creative science thinking.
Modeling and experimental study on near-field acoustic levitation by flexural mode.
Liu, Pinkuan; Li, Jin; Ding, Han; Cao, Wenwu
2009-12-01
Near-field acoustic levitation (NFAL) has been used in noncontact handling and transportation of small objects to avoid contamination. We have performed a theoretical analysis based on nonuniform vibrating surface to quantify the levitation force produced by the air film and also conducted experimental tests to verify our model. Modal analysis was performed using ANSYS on the flexural plate radiator to obtain its natural frequency of desired mode, which is used to design the measurement system. Then, the levitation force was calculated as a function of levitation distance based on squeeze gas film theory using measured amplitude and phase distributions on the vibrator surface. Compared with previous fluid-structural analyses using a uniform piston motion, our model based on the nonuniform radiating surface of the vibrator is more realistic and fits better with experimentally measured levitation force.
PSO-based PID Speed Control of Traveling Wave Ultrasonic Motor under Temperature Disturbance
NASA Astrophysics Data System (ADS)
Arifin Mat Piah, Kamal; Yusoff, Wan Azhar Wan; Azmi, Nur Iffah Mohamed; Romlay, Fadhlur Rahman Mohd
2018-03-01
Traveling wave ultrasonic motors (TWUSMs) have a time varying dynamics characteristics. Temperature rise in TWUSMs remains a problem particularly in sustaining optimum speed performance. In this study, a PID controller is used to control the speed of TWUSM under temperature disturbance. Prior to developing the controller, a linear approximation model which relates the speed to the temperature is developed based on the experimental data. Two tuning methods are used to determine PID parameters: conventional Ziegler-Nichols(ZN) and particle swarm optimization (PSO). The comparison of speed control performance between PSO-PID and ZN-PID is presented. Modelling, simulation and experimental work is carried out utilizing Fukoku-Shinsei USR60 as the chosen TWUSM. The results of the analyses and experimental work reveal that PID tuning using PSO-based optimization has the advantage over the conventional Ziegler-Nichols method.
The Role of Technology-Based Scaffolding in Problem-Based Online Asynchronous Discussion
ERIC Educational Resources Information Center
Ak, Serife
2016-01-01
This study examined the effects of technology-based scaffolds that were composed through the use of the seven-stage, problem-based learning strategy on knowledge construction in a problem-based online asynchronous discussion. In a quasi-experimental setting, 60 students in an undergraduate Instructional Technology and Material Design course were…
A summary of research-based assessment of students' beliefs about the nature of experimental physics
NASA Astrophysics Data System (ADS)
Wilcox, Bethany R.; Lewandowski, H. J.
2018-03-01
Within the undergraduate physics curriculum, students' primary exposure to experimental physics comes from laboratory courses. Thus, as experimentation is a core component of physics as a discipline, lab courses can be gateways in terms of both recruiting and retaining students within the physics major. Physics lab courses have a wide variety of explicit and/or implicit goals for lab courses, including helping students to develop expert-like beliefs about the nature and importance of experimental physics. To assess students' beliefs, attitudes, and expectations about the nature of experimental physics, there is currently one research-based assessment instrument available—the Colorado Learning Attitudes about Science Survey for Experimental Physics (E-CLASS). Since its development, the E-CLASS has been the subject of multiple research studies aimed at understanding and evaluating the effectiveness of various laboratory learning environments. This paper presents a description of the E-CLASS assessment and a summary of the research that has been done using E-CLASS data with a particular emphasis on the aspects of this work that are most relevant for instructors.
Definition of smolder experiments for Spacelab
NASA Technical Reports Server (NTRS)
Summerfield, M.; Messina, N. A.; Ingram, L. S.
1979-01-01
The feasibility of conducting experiments in space on smoldering combustion was studied to conceptually design specific smoldering experiments to be conducted in the Shuttle/Spacelab System. Design information for identified experiment critical components is provided. The analytical and experimental basis for conducting research on smoldering phenomena in space was established. Physical descriptions of the various competing processes pertaining to smoldering combustion were identified. The need for space research was defined based on limitations of existing knowledge and limitations of ground-based reduced-gravity experimental facilities.
Experimental Investigation of Electrical Conductivity and Permittivity of SC-TiO 2 -EG Nanofluids.
Fal, Jacek; Barylyak, Adriana; Besaha, Khrystyna; Bobitski, Yaroslav V; Cholewa, Marian; Zawlik, Izabela; Szmuc, Kamil; Cebulski, Józef; Żyła, Gaweł
2016-12-01
The paper presents experimental studies of dielectric properties of nanofluids based on ethylene glycol and SC-TiO2 nanoparticles with average size of 15-40 nm with various mass concentrations. The dielectric permittivity both real part and imaginary part as a function of temperature and frequency were measured. Also, dependence ac conductivity on frequency, temperature, and mass concentration were investigated. Based on the curves of ac conductivity, dc conductivity was calculated, and 400 % enhancement in dc conductivity was exposed.
Experimental Investigation of Electrical Conductivity and Permittivity of SC-TiO 2 -EG Nanofluids
NASA Astrophysics Data System (ADS)
Fal, Jacek; Barylyak, Adriana; Besaha, Khrystyna; Bobitski, Yaroslav V.; Cholewa, Marian; Zawlik, Izabela; Szmuc, Kamil; Cebulski, Józef; żyła, Gaweł
2016-08-01
The paper presents experimental studies of dielectric properties of nanofluids based on ethylene glycol and SC-TiO2 nanoparticles with average size of 15-40 nm with various mass concentrations. The dielectric permittivity both real part and imaginary part as a function of temperature and frequency were measured. Also, dependence ac conductivity on frequency, temperature, and mass concentration were investigated. Based on the curves of ac conductivity, dc conductivity was calculated, and 400 % enhancement in dc conductivity was exposed.
Origin of traps and charge transport mechanism in hafnia
DOE Office of Scientific and Technical Information (OSTI.GOV)
Islamov, D. R., E-mail: damir@isp.nsc.ru; Gritsenko, V. A., E-mail: grits@isp.nsc.ru; Novosibirsk State University, Novosibirsk 630090
2014-12-01
In this study, we demonstrated experimentally and theoretically that oxygen vacancies are responsible for the charge transport in HfO{sub 2}. Basing on the model of phonon-assisted tunneling between traps, and assuming that the electron traps are oxygen vacancies, good quantitative agreement between the experimental and theoretical data of current-voltage characteristics was achieved. The thermal trap energy of 1.25 eV in HfO{sub 2} was determined based on the charge transport experiments.
Improving Transfer of Learning through Designed Context-Based Instructional Materials
ERIC Educational Resources Information Center
Bahtaji, Michael Allan A.
2015-01-01
This study investigates the outcome of designed source-text materials in context-based physics learning using validated test questions in mechanics. Two groups of students received context-based instruction (experimental group) and one group received content-based instruction (control group). These three groups of students are only different with…
Maleke, Caroline; Luo, Jianwen; Gamarnik, Viktor; Lu, Xin L; Konofagou, Elisa E
2010-07-01
The objective of this study is to show that Harmonic Motion Imaging (HMI) can be used as a reliable tumor-mapping technique based on the tumor's distinct stiffness at the early onset of disease. HMI is a radiation-force-based imaging method that generates a localized vibration deep inside the tissue to estimate the relative tissue stiffness based on the resulting displacement amplitude. In this paper, a finite-element model (FEM) study is presented, followed by an experimental validation in tissue-mimicking polyacrylamide gels and excised human breast tumors ex vivo. This study compares the resulting tissue motion in simulations and experiments at four different gel stiffnesses and three distinct spherical inclusion diameters. The elastic moduli of the gels were separately measured using mechanical testing. Identical transducer parameters were used in both the FEM and experimental studies, i.e., a 4.5-MHz single-element focused ultrasound (FUS) and a 7.5-MHz diagnostic (pulse-echo) transducer. In the simulation, an acoustic pressure field was used as the input stimulus to generate a localized vibration inside the target. Radiofrequency (rf) signals were then simulated using a 2D convolution model. A one-dimensional cross-correlation technique was performed on the simulated and experimental rf signals to estimate the axial displacement resulting from the harmonic radiation force. In order to measure the reliability of the displacement profiles in estimating the tissue stiffness distribution, the contrast-transfer efficiency (CTE) was calculated. For tumor mapping ex vivo, a harmonic radiation force was applied using a 2D raster-scan technique. The 2D HMI images of the breast tumor ex vivo could detect a malignant tumor (20 x 10 mm2) surrounded by glandular and fat tissues. The FEM and experimental results from both gels and breast tumors ex vivo demonstrated that HMI was capable of detecting and mapping the tumor or stiff inclusion with various diameters or stiffnesses. HMI may thus constitute a promising technique in tumor detection (>3 mm in diameter) and mapping based on its distinct stiffness.
Boonyasopun, Umaporn; Aree, Patcharaporn; Avant, Kay C
2008-06-01
This quasi-experimental study examined the effects of an empowerment-based nutrition promotion program on food consumption and serum lipid levels among hyperlipidemic Thai elderly. Fifty-six experimental subjects received the program; 48 control subjects maintained their habitual lifestyle. The statistical methods used were the t-test, Z-test, and chi2/Fisher's exact test. After the program, the consumption of high saturated fat, cholesterol, and simple sugar diets was significantly lower for the experimental group than for the control group. The percentage change of the serum total cholesterol of the experimental subjects was significantly higher than that of the control subjects. The number of experimental subjects that changed from hyperlipidemia to normolipidemia significantly increased compared to that for the control subjects. The implementation of this program was related to an improvement in food consumption and serum lipid levels among hyperlipidemic Thai elderly and, therefore, has implications for practice.
ERIC Educational Resources Information Center
Hogenes, Michel; van Oers, Bert; Diekstra, René F. W.; Sklad, Marcin
2016-01-01
The present study aims to contribute to the understanding of the effects of music education, in particular music composition as a classroom activity for fifth- and sixth-graders. The intervention (experimental condition) focused on a three-step-model for music composition, based on the Cultural Historical Activity Theory of education, and has been…
ERIC Educational Resources Information Center
Dresel, Markus; Rindermann, Heiner
2011-01-01
Counseling instructors using evaluations made by their students has shown to be a fruitful approach to enhancing teaching quality. However, prior experimental studies are questionable in terms of external validity. Therefore, we conducted a non-experimental intervention study in which all of the courses offered by a specific department at a German…
Ahn, Si-Nae; Yoo, Eun-Young; Jung, Min-Ye; Park, Hae-Yean; Lee, Ji-Yeon; Choi, Yoo-Im
2017-01-01
Cognitive Orientation to daily Occupational Performance (CO-OP) approach based on cognitive strategy in occupational therapy. To investigate the effects of CO-OP approach on occupational performance in individuals with hemiparetic stroke. This study was designed as a 5-week, randomized, single-blind. Forty-three participants who had a diagnosis of first stroke were enrolled in this study. The participants were randomly assigned to the experimental group (n = 20) or the control group (n = 23). The experimental group conducted CO-OP approach while the control group conducted conventional occupational therapy based on occupational performance components. This study measured Canadian Occupational Performance Measure (COPM) and Performance Quality Rating Scale (PQRS). Outcome measurements were performed at baseline and post-intervention. After training, the scores of COPM and PQRS in trained task were significantly higher for the score in the experimental group than the control group. In addition, the non-trained task was significantly higher for the score in the experimental group than the control group in COPM and the PQRS. This study suggests that the CO-OP approach is beneficial effects on the occupational performance to improvement in individuals with hemiparetic stroke, and have positive effects on generalization and transfer of acquired skills.
Incretin-Based Therapies for Diabetic Complications: Basic Mechanisms and Clinical Evidence
Kawanami, Daiji; Matoba, Keiichiro; Sango, Kazunori; Utsunomiya, Kazunori
2016-01-01
An increase in the rates of morbidity and mortality associated with diabetic complications is a global concern. Glycemic control is important to prevent the development and progression of diabetic complications. Various classes of anti-diabetic agents are currently available, and their pleiotropic effects on diabetic complications have been investigated. Incretin-based therapies such as dipeptidyl peptidase (DPP)-4 inhibitors and glucagon-like peptide-1 receptor agonists (GLP-1RA) are now widely used in the treatment of patients with type 2 diabetes. A series of experimental studies showed that incretin-based therapies have beneficial effects on diabetic complications, independent of their glucose-lowering abilities, which are mediated by anti-inflammatory and anti-oxidative stress properties. Based on these findings, clinical studies to assess the effects of DPP-4 inhibitors and GLP-1RA on diabetic microvascular and macrovascular complications have been performed. Several but not all studies have provided evidence to support the beneficial effects of incretin-based therapies on diabetic complications in patients with type 2 diabetes. We herein discuss the experimental and clinical evidence of incretin-based therapy for diabetic complications. PMID:27483245
Charlwood, J. Derek; Harrington, Laura C.; Lounibos, L. Philip; Reisen, William K.; Tabachnick, Walter J.
2018-01-01
Abstract Experimental releases of mosquitoes are performed to understand characteristics of populations related to the biology, ability to transmit pathogens, and ultimately their control. In this article, we discuss considerations related to the safety of experimental releases of living mosquitoes, applying principles of good practice in vector biology that protect human health and comfort. We describe specific factors of experimental releases of mosquitoes that we believe are critical to inform institutional biosafety committees and similar review boards to which proposals to conduct mosquito release experiments have been submitted. In this study, “experimental releases” means those that do not significantly increase vector capacity or nuisance biting relative to the unperturbed natural baseline. This document specifically does not address releases of mosquitoes for ongoing control programs or trials of new control methods for which broader assessments of risk are required. It also does not address releases of transgenic or exotic (non-native) mosquito species, both of which require particular regulatory approval. Experimental releases may include females and males and evaluation must consider their effects based on the number released, their genotype and phenotype, the environment into which they are released, and postrelease collection activities. We consider whether increases of disease transmission and nuisance biting might result from proposed experimental releases against the backdrop of natural population size variation. We recommend that experimental releases be conducted in a manner that can be reasonably argued to have insignificant negative effects. Reviewers of proposals for experimental releases should expect applicants to provide such an argument based on evidence from similar studies and their planned activities. This document provides guidance for creating and evaluating such proposals. PMID:29337660
Benedict, Mark Q; Charlwood, J Derek; Harrington, Laura C; Lounibos, L Philip; Reisen, William K; Tabachnick, Walter J
2018-01-01
Experimental releases of mosquitoes are performed to understand characteristics of populations related to the biology, ability to transmit pathogens, and ultimately their control. In this article, we discuss considerations related to the safety of experimental releases of living mosquitoes, applying principles of good practice in vector biology that protect human health and comfort. We describe specific factors of experimental releases of mosquitoes that we believe are critical to inform institutional biosafety committees and similar review boards to which proposals to conduct mosquito release experiments have been submitted. In this study, "experimental releases" means those that do not significantly increase vector capacity or nuisance biting relative to the unperturbed natural baseline. This document specifically does not address releases of mosquitoes for ongoing control programs or trials of new control methods for which broader assessments of risk are required. It also does not address releases of transgenic or exotic (non-native) mosquito species, both of which require particular regulatory approval. Experimental releases may include females and males and evaluation must consider their effects based on the number released, their genotype and phenotype, the environment into which they are released, and postrelease collection activities. We consider whether increases of disease transmission and nuisance biting might result from proposed experimental releases against the backdrop of natural population size variation. We recommend that experimental releases be conducted in a manner that can be reasonably argued to have insignificant negative effects. Reviewers of proposals for experimental releases should expect applicants to provide such an argument based on evidence from similar studies and their planned activities. This document provides guidance for creating and evaluating such proposals.
Avci, Dilek; Kelleci, Meral
2016-04-01
This study aimed to determine the effects of an Anger Coping Programme based on cognitive behavioural techniques on adolescents' anger, aggression and psychological symptoms. In this randomized controlled experimental study, 385 ninth-year high school students in Turkey were administered the State-Trait Anger Expression Inventory, the Aggression Scale and the Brief Symptom Inventory in 2011-2012. Of the 385 students, 62 who met the inclusion criteria were randomly assigned to experimental and control groups by gender and the scores they obtained from the scales. The students in the experimental group met 1 day a week for 1.5 h, and the study lasted 10 weeks. The scales were administered three times: before the programme was started, immediately after the programme was completed and 6 weeks later. The Anger Coping Programme was effective at reducing students' anger and aggression levels, and a range of psychological symptoms except for somatization. © 2015 John Wiley & Sons Australia, Ltd.
A Combined Theoretical and Experimental Study for Silver Electroplating
Liu, Anmin; Ren, Xuefeng; An, Maozhong; Zhang, Jinqiu; Yang, Peixia; Wang, Bo; Zhu, Yongming; Wang, Chong
2014-01-01
A novel method combined theoretical and experimental study for environmental friendly silver electroplating was introduced. Quantum chemical calculations and molecular dynamic (MD) simulations were employed for predicting the behaviour and function of the complexing agents. Electronic properties, orbital information, and single point energies of the 5,5-dimethylhydantoin (DMH), nicotinic acid (NA), as well as their silver(I)-complexes were provided by quantum chemical calculations based on density functional theory (DFT). Adsorption behaviors of the agents on copper and silver surfaces were investigated using MD simulations. Basing on the data of quantum chemical calculations and MD simulations, we believed that DMH and NA could be the promising complexing agents for silver electroplating. The experimental results, including of electrochemical measurement and silver electroplating, further confirmed the above prediction. This efficient and versatile method thus opens a new window to study or design complexing agents for generalized metal electroplating and will vigorously promote the level of this research region. PMID:24452389
Knowledge synthesis with maps of neural connectivity.
Tallis, Marcelo; Thompson, Richard; Russ, Thomas A; Burns, Gully A P C
2011-01-01
This paper describes software for neuroanatomical knowledge synthesis based on neural connectivity data. This software supports a mature methodology developed since the early 1990s. Over this time, the Swanson laboratory at USC has generated an account of the neural connectivity of the sub-structures of the hypothalamus, amygdala, septum, hippocampus, and bed nucleus of the stria terminalis. This is based on neuroanatomical data maps drawn into a standard brain atlas by experts. In earlier work, we presented an application for visualizing and comparing anatomical macro connections using the Swanson third edition atlas as a framework for accurate registration. Here we describe major improvements to the NeuARt application based on the incorporation of a knowledge representation of experimental design. We also present improvements in the interface and features of the data mapping components within a unified web-application. As a step toward developing an accurate sub-regional account of neural connectivity, we provide navigational access between the data maps and a semantic representation of area-to-area connections that they support. We do so based on an approach called "Knowledge Engineering from Experimental Design" (KEfED) model that is based on experimental variables. We have extended the underlying KEfED representation of tract-tracing experiments by incorporating the definition of a neuronanatomical data map as a measurement variable in the study design. This paper describes the software design of a web-application that allows anatomical data sets to be described within a standard experimental context and thus indexed by non-spatial experimental design features.
The history of gold therapy for tuberculosis.
Benedek, Thomas G
2004-01-01
This is a historical study of the popularization of a medical therapy contrary to pertinent experimental findings. Presumably this circumstance reflects the desperation about tuberculosis: highly prevalent, highly fatal, and lacking any etiologically directed therapy. Gold compounds were introduced, based initially on the reputation of Robert Koch, who had found gold cyanide effective against M. tuberculosis in cultures, but not in experimentally infected animals. Treatment of pulmonary tuberculosis with these compounds was popularized, particularly by Danish physicians, in the mid-1920s, despite consistently negative experimental results, based on Paul Ehrlich's theories of antimicrobial drug effects. Difficulties in the design of interpretable clinical studies were soon recognized but also generally ignored, thus permitting data to be interpreted as favorable to antituberculous gold therapy. Eventually toxicity was considered to outweigh the alleged therapeutic benefit of all gold compounds. This resulted in their discard shortly before the introduction of streptomycin therapy.
Zhang, Hang; Xu, Qingyan
2017-10-27
Grain selection is an important process in single crystal turbine blades manufacturing. Selector structure is a control factor of grain selection, as well as directional solidification (DS). In this study, the grain selection and structure design of the spiral selector were investigated through experimentation and simulation. A heat transfer model and a 3D microstructure growth model were established based on the Cellular automaton-Finite difference (CA-FD) method for the grain selector. Consequently, the temperature field, the microstructure and the grain orientation distribution were simulated and further verified. The average error of the temperature result was less than 1.5%. The grain selection mechanisms were further analyzed and validated through simulations. The structural design specifications of the selector were suggested based on the two grain selection effects. The structural parameters of the spiral selector, namely, the spiral tunnel diameter ( d w ), the spiral pitch ( h b ) and the spiral diameter ( h s ), were studied and the design criteria of these parameters were proposed. The experimental and simulation results demonstrated that the improved selector could accurately and efficiently produce a single crystal structure.
Zhang, Hang; Xu, Qingyan
2017-01-01
Grain selection is an important process in single crystal turbine blades manufacturing. Selector structure is a control factor of grain selection, as well as directional solidification (DS). In this study, the grain selection and structure design of the spiral selector were investigated through experimentation and simulation. A heat transfer model and a 3D microstructure growth model were established based on the Cellular automaton-Finite difference (CA-FD) method for the grain selector. Consequently, the temperature field, the microstructure and the grain orientation distribution were simulated and further verified. The average error of the temperature result was less than 1.5%. The grain selection mechanisms were further analyzed and validated through simulations. The structural design specifications of the selector were suggested based on the two grain selection effects. The structural parameters of the spiral selector, namely, the spiral tunnel diameter (dw), the spiral pitch (hb) and the spiral diameter (hs), were studied and the design criteria of these parameters were proposed. The experimental and simulation results demonstrated that the improved selector could accurately and efficiently produce a single crystal structure. PMID:29077067
Computational study of AuSi{sub n} (n=1-9) nanoalloy clusters invoking DFT based descriptors
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ranjan, Prabhat; Kumar, Ajay; Chakraborty, Tanmoy, E-mail: tanmoy.chakraborty@jaipur.manipal.edu, E-mail: tanmoychem@gmail.com
2016-04-13
Nanoalloy clusters formed between Au and Si are topics of great interest today from both scientific and technological point of view. Due to its remarkable catalytic, electronic, mechanical and magnetic properties Au-Si nanoalloy clusters have extensive applications in the field of microelectronics, catalysis, biomedicine, and jewelry industry. Density Functional Theory (DFT) is a new paradigm of quantum mechanics, which is very much popular to study the electronic properties of materials. Conceptual DFT based descriptors have been invoked to correlate the experimental properties of nanoalloy clusters. In this venture, we have systematically investigated AuSi{sub n} (n=1-9) nanoalloy clusters in the theoreticalmore » frame of the B3LYP exchange correlation. The experimental properties of AuSi{sub n} (n=1-9) nanoalloy clusters are correlated in terms of DFT based descriptors viz. HOMO-LUMO gap, Electronegativity (χ), Global Hardness (η), Global Softness (S) and Electrophilicity Index (ω). The calculated HOMO-LUMO gap exhibits interesting odd-even alteration behaviour, indicating that even numbered clusters possess higher stability as compare to their neighbour odd numbered clusters. This study also reflects a very well agreement between experimental bond length and computed data.« less
Lee, Eun Mi; Kim, Hyunlye
2017-04-01
This study was done to develop a children's sex education program for the parents of lower elementary grade students and to evaluate its effects on sexual knowledge, gender role attitude, parent efficacy for child's sex education, and marital consistency. A quasi-experimental with a non-equivalent control group pretest-posttest design was used. The participants were 29 couples (58 parents, experimental group=28, control group=30) from G city. The 5-week (5-session) program was developed based on 'A theory of protection: parents as sex educators' and used the case-based small group learning method. Data were collected during July and August 2015. The characteristics of the program developed in the present study were a theoretical-based, client-centered, multi-method. After the intervention, the experimental group showed a significant improvement in sexual knowledge, gender role attitudes, parent efficacy for child's sex education, and marital consistency, compared to the control group. The effect sizes of the program were .64 (knowledge), .65 (gender role attitudes), and .68 (parent efficacy). The results of this study provided implications for the parents as effective sex educator and the role expansion of school health nurses. © 2017 Korean Society of Nursing Science
Experimental Research on the Dense CFB's Riser and the Simulation Based on the EMMS Model
NASA Astrophysics Data System (ADS)
Wang, X. Y.; Wang, S. D.; Fan, B. G.; Liao, L. L.; Jiang, F.; Xu, X.; Wu, X. Z.; Xiao, Y. H.
2010-03-01
The flow structure in the CFB (circulating fluidized bed) riser has been investigated. Experimental studies were performed in a cold square section unit with 270 mm×270 mm×10 m. Since the drag force model based on homogeneous two-phase flow such as the Gidaspow drag model could not depict the heterogeneous structures of the gas-solid flow, the structure-dependent energy-minimization multi-scale (EMMS) model based on the heterogenerity was applied in the paper and a revised drag force model based on the EMMS model was proposed. A 2D two-fluid model was used to simulate a bench-scale square cross-section riser of a cold CFB. The typical core-annulus structure and the back-mixing near the wall of the riser were observed and the assembly and fragmentation processes of clusters were captured. By comparing with the Gidaspow drag model, the results obtained by the revised drag model based on EMMS shows better consistency with the experimental data. The model can also depict the difference from the two exit configurations. This study once again proves the key role of drag force in CFD (Computational Fluid Dynamics) simulation and also shows the availability of the revised drag model to describe the gas-solid flow in CFB risers.
Garfinkel, L; Cohen, D M; Soo, V W; Garfinkel, D; Kulikowski, C A
1989-01-01
We have developed a computer method based on artificial-intelligence techniques for qualitatively analysing steady-state initial-velocity enzyme kinetic data. We have applied our system to experiments on hexokinase from a variety of sources: yeast, ascites and muscle. Our system accepts qualitative stylized descriptions of experimental data, infers constraints from the observed data behaviour and then compares the experimentally inferred constraints with corresponding theoretical model-based constraints. It is desirable to have large data sets which include the results of a variety of experiments. Human intervention is needed to interpret non-kinetic information, differences in conditions, etc. Different strategies were used by the several experimenters whose data was studied to formulate mechanisms for their enzyme preparations, including different methods (product inhibitors or alternate substrates), different experimental protocols (monitoring enzyme activity differently), or different experimental conditions (temperature, pH or ionic strength). The different ordered and rapid-equilibrium mechanisms proposed by these experimenters were generally consistent with their data. On comparing the constraints derived from the several experimental data sets, they are found to be in much less disagreement than the mechanisms published, and some of the disagreement can be ascribed to different experimental conditions (especially ionic strength). PMID:2690819
Requirements for Real-Time Laboratory Experimentation over the Internet.
ERIC Educational Resources Information Center
Salzmann, C.; Latchman, H. A.; Gillet, D.; Crisalle, O. D.
A prototype system based on an inverted pendulum is used to study the Quality of Service and discuss requirements of remote-experimentation systems utilized for carrying out control engineering experiments over the Internet. This class of applications involves the transmission over the network of a variety of data types with their own peculiar…
Student and Teacher Outcomes of The Superkids Quasi-Experimental Study
ERIC Educational Resources Information Center
Borman, Geoffrey D.; Dowling, N. Maritza
2009-01-01
In this article, we report kindergarten student and teacher outcomes from a quasi-experimental evaluation of The Superkids, a systematic, phonics-based, comprehensive K-2 reading program. We recruited 23 kindergarten teachers to implement The Superkids program from a diverse, yet predominantly ethnic minority, group of classrooms from across the…
Sexual Violence Prevention through Bystander Education: An Experimental Evaluation
ERIC Educational Resources Information Center
Banyard, Victoria L.; Moynihan, Mary M.; Plante, Elizabethe G.
2007-01-01
The current study used an experimental design to evaluate a sexual violence prevention program based on a community of responsibility model that teaches women and men how to intervene safely and effectively in cases of sexual violence before, during, and after incidents with strangers, acquaintances, or friends. It approaches both women and men as…
ERIC Educational Resources Information Center
Smith, Kasee L.; Rayfield, John
2017-01-01
Understanding methods for effectively instructing STEM education concepts is essential in the current climate of education (Freeman, Marginson, & Tyler 2014). Kolb's experiential learning theory (ELT) outlines four specific modes of learning, based on preferences for grasping and transforming information. This quasi-experimental study was…
Investigation of Effective Strategies for Developing Creative Science Thinking
ERIC Educational Resources Information Center
Yang, Kuay-Keng; Lee, Ling; Hong, Zuway-R; Lin, Huann-shyang
2016-01-01
The purpose of this study was to explore the effectiveness of the creative inquiry-based science teaching on students' creative science thinking and science inquiry performance. A quasi-experimental design consisting one experimental group (N = 20) and one comparison group (N = 24) with pretest and post-test was conducted. The framework of the…
Instream-Flow Analysis for the Luquillo Experimental Forest, Puerto Rico: Methods and Analysis
F.N. Scatena; S.L. Johnson
2001-01-01
This study develops two habitat-based approaches for evaluating instream-flow requirements within the Luquillo Experimental Forest in northeastern Puerto Rico. The analysis is restricted to instream-flow requirements in upland streams dominated by the common communities of freshwater decapods. In headwater streams, pool volume was the most consistent factor...
Helping Students Make Sense of Graphs: An Experimental Trial of SmartGraphs Software
ERIC Educational Resources Information Center
Zucker, Andrew; Kay, Rachel; Staudt, Carolyn
2014-01-01
Graphs are commonly used in science, mathematics, and social sciences to convey important concepts; yet students at all ages demonstrate difficulties interpreting graphs. This paper reports on an experimental study of free, Web-based software called SmartGraphs that is specifically designed to help students overcome their misconceptions regarding…
Fort Valley studies: A natural laboratory for research and education
Brian W. Geils
2008-01-01
Drought, wildfire, extinction, and invasive species are considered serious threats to the health of our forests. Although these issues have global connections, we most readily see their consequences locally and attempt to respond with management based on science. For 100 years, the Fort Valley Experimental Forest (FVEF) has provided educational and experimental support...
Experimental Study of Sudden Solidification of Supercooled Water
ERIC Educational Resources Information Center
Bochnícek, Zdenek
2014-01-01
The two independent methods of measurement of the mass of ice created at sudden solidification of supercooled water are described. One is based on the calorimetric measurement of heat that is necessary for melting the ice and the second interprets the volume change that accompanies the water freezing. Experimental results are compared with the…
Applications of Small Area Estimation to Generalization with Subclassification by Propensity Scores
ERIC Educational Resources Information Center
Chan, Wendy
2018-01-01
Policymakers have grown increasingly interested in how experimental results may generalize to a larger population. However, recently developed propensity score-based methods are limited by small sample sizes, where the experimental study is generalized to a population that is at least 20 times larger. This is particularly problematic for methods…
ERIC Educational Resources Information Center
Simons, Lori; Giorgio, Tina; Houston, Hank; Jacobucci, Ray
2007-01-01
A secondary analysis of a quasi-experimental study was conducted to evaluate differences in students 'perceptions of empirically supported treatments (ESTS) randomized to experimental (n= 10) and attention-control (n= 10) manual-based therapy interventions. The results indicated that attitudinal changes took place for both groups. The results…
Rabani-Bavojdan, Marjan; Rabani-Bavojdan, Mozhgan; Rajabizadeh, Ghodratollah; Kaviani, Nahid; Bahramnejad, Ali; Ghaffari, Zohreh; Shafiei-Bafti, Mehdi
2017-07-01
The aim of this study was to investigate the effectiveness of the harm reduction group therapy based on Bandura's self-efficacy theory on risky behaviors of sex workers in Kerman, Iran. A quasi-experimental two-group design (a random selection with pre-test and post-test) was used. A risky behaviors questionnaire was used to collect. The sample was selected among sex workers referring to drop-in centers in Kerman. Subjects were allocated to two groups and were randomly classified into two experimental and control groups. The sample group consisted of 56 subjects. The experimental design was carried out during 12 sessions, and the post-test was performed one month and two weeks after the completion of the sessions. The results were analyzed statistically. By reducing harm based on Bandura's self-efficacy theory, the risky behaviors of the experimental group, including injection behavior, sexual behavior, violence, and damage to the skin, were significantly reduced in the pre-test compared to the post-test (P < 0.010). The harm reduction group therapy based on Bandura's self-efficacy theory can reduce the risky behaviors of sex workers.
NASA Astrophysics Data System (ADS)
Iyahraja, S.; Rajadurai, J. Selwin; Rajesh, S.; Pandian, R. Seeni Thangaraj; Kumaran, M. Selva; Selvakumar, G.
2018-07-01
In the present study, performance of convective heat transfer and friction factor of silver-water nanofluids in a horizontal circular pipe under turbulent flow were investigated experimentally under uniform heat flux condition. The volume concentration of silver nanoparticles is varied as 0.01, 0.05 and 0.1%. Heat transfer coefficient and friction factor of nanofluids were measured experimentally by varying the Reynolds number from 3000 to 21,000. It is observed that the addition of even low volume fraction of silver nanoparticles increases both Nusselt number and heat transfer coefficient of the nanofluid significantly. Nusselt number of silver-water nanofluid increases up to 32.6% for 0.1% volume fraction at Reynolds number of 21,000. However, the addition of nanoparticles in the base fluid increases the friction factor slightly. New empirical correlations are also proposed for the estimation of Nusselt number and friction factor of silver-water nanofluid based on the data of present experimental investigation. The proposed correlations of Nusselt number and friction factor show good agreement with their experimental data.
NASA Astrophysics Data System (ADS)
Iyahraja, S.; Rajadurai, J. Selwin; Rajesh, S.; Pandian, R. Seeni Thangaraj; Kumaran, M. Selva; Selvakumar, G.
2018-02-01
In the present study, performance of convective heat transfer and friction factor of silver-water nanofluids in a horizontal circular pipe under turbulent flow were investigated experimentally under uniform heat flux condition. The volume concentration of silver nanoparticles is varied as 0.01, 0.05 and 0.1%. Heat transfer coefficient and friction factor of nanofluids were measured experimentally by varying the Reynolds number from 3000 to 21,000. It is observed that the addition of even low volume fraction of silver nanoparticles increases both Nusselt number and heat transfer coefficient of the nanofluid significantly. Nusselt number of silver-water nanofluid increases up to 32.6% for 0.1% volume fraction at Reynolds number of 21,000. However, the addition of nanoparticles in the base fluid increases the friction factor slightly. New empirical correlations are also proposed for the estimation of Nusselt number and friction factor of silver-water nanofluid based on the data of present experimental investigation. The proposed correlations of Nusselt number and friction factor show good agreement with their experimental data.
Numerical modelling and experimental study of liquid evaporation during gel formation
NASA Astrophysics Data System (ADS)
Pokusaev, B. G.; Khramtsov, D. P.
2017-11-01
Gels are promising materials in biotechnology and medicine as a medium for storing cells for bioprinting applications. Gel is a two-phase system consisting of solid medium and liquid phase. Understanding of a gel structure evolution and gel aging during liquid evaporation is a crucial step in developing new additive bioprinting technologies. A numerical and experimental study of liquid evaporation was performed. In experimental study an evaporation process of an agarose gel layer located on Petri dish was observed and mass difference was detected using electronic scales. Numerical model was based on a smoothed particle hydrodynamics method. Gel in a model was represented as a solid-liquid system and liquid evaporation was modelled due to capillary forces and heat transfer. Comparison of experimental data and numerical results demonstrated that model can adequately represent evaporation process in agarose gel.
2006-04-17
of the droplet phase are then used for validation of theoretical models of the gas-droplet plume flow. Based on experimental and numerical results...with the continuous model adequately reproduces the Arrhenius rate at high temperatures but significantly underpredicts the theoretical rate at low...continuous model and discrete model of real gas effects, and the results on the shock -wave stand-off distance were compared with the experimental data of
Evaluation of an Experimental Adhesive Resin for Orthodontic Bonding
NASA Astrophysics Data System (ADS)
Durgesh, B. H.; Alkheraif, A. A.; Pavithra, D.; Hashem, M. I.; Alkhudhairy, F.; Elsharawy, M.; Divakar, D. D.; Vallittu, P. K.; Matinlinna, J. P.
2017-07-01
The aim of this study was to evaluate in vitro the effect of an experimental adhesive resin for orthodontic bonding by measuring some the chemical and mechanical properties. The resin demonstrated increased values of nanohardness and elastic modulus, but the differences were not significant compared with those for the Transbond XT adhesives. The experimental adhesive resin could be a feasible choice or a substitute for the traditional bis-GMA-based resins used in bonding orthodontic attachments.
Desynchronization of stochastically synchronized chemical oscillators
DOE Office of Scientific and Technical Information (OSTI.GOV)
Snari, Razan; Tinsley, Mark R., E-mail: mark.tinsley@mail.wvu.edu, E-mail: kshowalt@wvu.edu; Faramarzi, Sadegh
Experimental and theoretical studies are presented on the design of perturbations that enhance desynchronization in populations of oscillators that are synchronized by periodic entrainment. A phase reduction approach is used to determine optimal perturbation timing based upon experimentally measured phase response curves. The effectiveness of the perturbation waveforms is tested experimentally in populations of periodically and stochastically synchronized chemical oscillators. The relevance of the approach to therapeutic methods for disrupting phase coherence in groups of stochastically synchronized neuronal oscillators is discussed.
Evidence Based Assessment of Public Health Planning: A Case Study of the 2014 Crisis in Ukraine
2015-06-12
Unknowns, Unknown Unknowns and the Propagation of Scientific Enquiry,” Journal of Experimental Botany 60, no. 3 (March 2009): 712-714. Risk...David C. Logan, “Known Knowns, Known Unknowns, Unknown Unknowns and the Propagation of Scientific Enquiry,” Journal of Experimental Botany 60, no. 3...Experimental Botany 60, no. 3 (March 2009): 712-714. Markel, Howard. “Facing Tuberculosis,” When Germs Travel: Six Major Epidemics That Have Invaded America
Tian, Zhen; Wang, Li-Zhen; Hu, Yu-Hua; Zhang, Chun-Ye; Li, Jiang
2017-04-01
Oral histopathology is a course which needs to be combined with theory and practice closely. Experimental course plays an important role in teaching oral histopathology. Here, we aim to explore a series of effective measures to improve the teaching quality of experimental course and tried to train observation, thinking, analysis and problem solving skills of dental students. We re-edited and updated the experimental textbook "guidelines of experimental course of oral histopathology", and published the reference book for experimental course--"color pocket atlas of oral histopathology: experiment and diadactic teaching". The number of clinicopathological cases for presentation and class discussion was increased, and high-quality teaching slides were added and replaced the poor-quality or worn out slides. We established a variety of teaching methods based on the internet, which provided an environment of self-directed learning for dental students. Instead of simple slice-reading examination, a new evaluation system based on computer was established. The questionnaire survey showed that the students spoke positively on the teaching reform for experimental course. They thought that the reform played a significant role in enriching the teaching content, motivating learning interest and promoting self-study. Compared with traditional examination, computer-based examination showed a great advantage on mastering professional knowledge systematically and comprehensively. The measures adopted in our teaching reform not only effectively improve the teaching quality of experimental course of oral histopathology, but also help the students to have a clear, logical thinking when facing complicated diseases and have the ability to apply theoretical knowledge into clinical practice.
Connecting Theory to Practice: Evaluating a Brain-Based Writing Curriculum
ERIC Educational Resources Information Center
Griffee, Dale T.
2007-01-01
This 10 week longitudinal evaluation study evaluated a brain-based learning curriculum proposed by Smilkstein (2003) by comparing student performance in a traditional basic writing curriculum with NHLP-oriented basic writing curriculum. The study included two classes each of experimental and traditional methods. Results of the data, gathered by…
ERIC Educational Resources Information Center
Kong, S. C.
2008-01-01
Two cycles of design-based research of a cognitive tool (CT) for teaching fractions have been completed. Following the success of a quasi-experimental study of the enhanced CT derived from the second cycle of design-based research, this article reports the findings of a pre-test-post-test control group empirical study using the enhanced CT in the…
ERIC Educational Resources Information Center
Serin, Oguz
2011-01-01
This study aims to investigate the effects of the computer-based instruction on the achievements and problem solving skills of the science and technology students. This is a study based on the pre-test/post-test control group design. The participants of the study consist of 52 students; 26 in the experimental group, 26 in the control group. The…
In silico prediction of pharmaceutical degradation pathways: a benchmarking study.
Kleinman, Mark H; Baertschi, Steven W; Alsante, Karen M; Reid, Darren L; Mowery, Mark D; Shimanovich, Roman; Foti, Chris; Smith, William K; Reynolds, Dan W; Nefliu, Marcela; Ott, Martin A
2014-11-03
Zeneth is a new software application capable of predicting degradation products derived from small molecule active pharmaceutical ingredients. This study was aimed at understanding the current status of Zeneth's predictive capabilities and assessing gaps in predictivity. Using data from 27 small molecule drug substances from five pharmaceutical companies, the evolution of Zeneth predictions through knowledge base development since 2009 was evaluated. The experimentally observed degradation products from forced degradation, accelerated, and long-term stability studies were compared to Zeneth predictions. Steady progress in predictive performance was observed as the knowledge bases grew and were refined. Over the course of the development covered within this evaluation, the ability of Zeneth to predict experimentally observed degradants increased from 31% to 54%. In particular, gaps in predictivity were noted in the areas of epimerizations, N-dealkylation of N-alkylheteroaromatic compounds, photochemical decarboxylations, and electrocyclic reactions. The results of this study show that knowledge base development efforts have increased the ability of Zeneth to predict relevant degradation products and aid pharmaceutical research. This study has also provided valuable information to help guide further improvements to Zeneth and its knowledge base.
ERIC Educational Resources Information Center
Chang, Chi-Cheng
2009-01-01
The purpose of this study was to explore the self-evaluated effects of a web-based portfolio assessment system on various categories of students of motivation. The subjects for this study were the students of two computer classes in a Junior High School. The experimental group used the web-based portfolio assessment system whereas the control…
ERIC Educational Resources Information Center
Stark, Robin; Kopp, Veronika; Fischer, Martin R.
2011-01-01
To investigate the effects of example format (erroneous examples vs. correct examples) and feedback format (elaborated feedback vs. knowledge of results feedback) on medical students' diagnostic competence in the context of a web-based learning environment containing case-based worked examples, two studies with a 2 x 2 design were conducted in the…
Effects of Web based inquiry on physical science teachers and students in an urban school district
NASA Astrophysics Data System (ADS)
Stephens, Joanne
An inquiry approach in teaching science has been advocated by many science educators for the past few decades. Due to insufficient district funding for science teaching, inadequate science laboratory facilities, and outdated science materials, inquiry teaching has been difficult for many science teachers, particularly science teachers in urban settings. However, research shows that the availability of computers with high speed Internet access has increased in all school districts. This study focused on the effects of inservice training on teachers and using web based science inquiry activities with ninth grade physical science students. Participants were 16 science teachers and 474 physical science students in an urban school district of a large southern U.S. city. Students were divided into control and experimental groups. The students in the experimental group participated in web based inquiry activities. Students in the control group were taught using similar methods, but not web based science activities. Qualitative and quantitative data were collected over a nine-week period using instruments and focus group interviews of students' and teachers' perceptions of the classroom learning environment, students' achievement, lesson design and classroom implementation, science content of lesson, and classroom culture. The findings reported that there were no significant differences in teachers' perception of the learning environment before and after implementing web based inquiry activities. The findings also reported that there were no overall significant differences in students' perceptions of the learning environment and achievement, pre-survey to post-survey, pre-test to post-test, between the control group and experimental group. Additional findings disclosed that students in the experimental group learned in a collaborative environment. The students confirmed that collaborating with others contributed to a deeper understanding of the science content. This study provides insights about utilizing technology to promote science inquiry teaching and learning. This study describes students' and teachers' perceptions of using web based inquiry to support scientific inquiry.
Experimental study of Bloch vector analysis in nonlinear, finite, dissipative systems
DOE Office of Scientific and Technical Information (OSTI.GOV)
D'Aguanno, G.; Mattiucci, N.; C. M. Bowden Facility, Building 7804, RDECOM, Redstone Arsenal, Alabama 35898
2010-01-15
We have investigated and experimentally demonstrated the applicability of the Bloch vector for one-dimensional, nonlinear, finite, dissipative systems. The case studied is the second harmonic generation from metallodielectric multilayer filters. In particular, we have applied the Bloch vector analysis to Ag/Ta{sub 2}O{sub 5} thin-film multilayer samples and shown the importance of the phase matching calculated through the Bloch vector. The nonlinear coefficients extracted from experimental results are consistent with previous studies. Nowadays, metal-based nanostructures play a fundamental role in nonlinear nanophotonics and nanoplasmonics. Our results clearly suggest that even in these forefront fields the Bloch vector continues to play anmore » essential role.« less
Laforest, Sophie; Lorthios-Guilledroit, Agathe; Nour, Kareen; Parisien, Manon; Fournier, Michel; Ellemberg, Dave; Guay, Danielle; Desgagn�s-Cyr, Charles-�mile; Bier, Nathalie
2017-01-01
Abstract This study examined the effects on attitudes and lifestyle behavior of Jog your Mind, a multi-factorial community-based program promoting cognitive vitality among seniors with no known cognitive impairment. A quasi-experimental study was conducted. Twenty-three community organizations were assigned either to the experimental group (offering the program) or to the control group (creating a waiting list). They recruited 294 community-dwelling seniors. The aims of the study were to verify the effects of the program on attitudes and behaviors related to cognitive vitality and to explore its effects on cognitive vitality. Data was collected at baseline and after the program. Regression analyses revealed that, following their participation in the program, experimental group participants reported: (i) in terms of attitudes, having a greater feeling of control concerning their cognitive capacities, (ii) in terms of behaviors, using significantly more memory strategies and practicing more physical activity and stimulating activities than control group participants. However, the program had no significant effects on measures of cognitive vitality. This study supports the fact that a multi-factorial community-based program can have significant effects on seniors’ attitudes and lifestyle behaviors related to cognitive vitality but at short term, no effects on cognitive vitality it-self were found. PMID:28334988
Grigorian, A S; Nabiev, F Kh; Golovin, R V
2005-01-01
In experimental study on 15 rabbits (chinchilla) influence of titanium plates implanted lapped on adjacent tissues in the region of the lower jaw body (comparison group) and carbon material with added boron in the concentrations of 8 and 15% (the study group) was studied. Results of the experimental-morphological investigation show that carbon-based materials with boron addition (with its content 8 and 15%) did not impede adaptive rebuilding of bone tissues and in particular bone structure regeneration in the process of reactive rebuilding of the "maternal" bone. Moreover, as the result of reactive processes developing in osseous tissues after implantation of the tested materials their successful integration in surrounding tissue structures was detected.
Ryhänen, Anne M; Siekkinen, Mervi; Rankinen, Sirkku; Korvenranta, Heikki; Leino-Kilpi, Helena
2010-04-01
The aim of this systematic review was to analyze what kind of Internet or interactive computer-based patient education programs have been developed and to analyze the effectiveness of these programs in the field of breast cancer patient education. Patient education for breast cancer patients is an important intervention to empower the patient. However, we know very little about the effects and potential of Internet-based patient education in the empowerment of breast cancer patients. Complete databases were searched covering the period from the beginning of each database to November 2008. Studies were included if they concerned patient education for breast cancer patients with Internet or interactive computer programs and were based on randomized controlled, on clinical trials or quasi-experimental studies. We identified 14 articles involving 2374 participants. The design was randomized controlled trial in nine papers, in two papers clinical trial and in three quasi-experimental. Seven of the studies were randomized to experimental and control groups, in two papers participants were grouped by ethnic and racial differences and by mode of Internet use and three studies measured the same group pre- and post-tests after using a computer program. The interventions used were described as interactive computer or multimedia programs and use of the Internet. The methodological solutions of the studies varied. The effects of the studies were diverse except for knowledge-related issues. Internet or interactive computer-based patient education programs in the care of breast cancer patients may have positive effect increasing breast cancer knowledge. The results suggest a positive relationship between the Internet or computer-based patient education program use and the knowledge level of patients with breast cancer but a diverse relationship between patient's participation and other outcome measures. There is need to develop and research more Internet-based patient education. 2009 Elsevier Ireland Ltd. All rights reserved.
ERIC Educational Resources Information Center
Uyanik, Gökhan
2016-01-01
The purpose of this study was to examine the effect of learning cycle approach-based teaching on academic achievement, attitude, motivation and retention at primary school 4th grade science lesson. It was conducted pretest-posttest quasi-experimental design in this study. The study was conducted on a total of 65 students studying in two different…
NASA Astrophysics Data System (ADS)
Egorov, A. G.; Kamalutdinov, A. M.; Nuriev, A. N.
2018-05-01
The paper is devoted to study of the aerodynamic forces acting on flat cantilever beams performing flexural vibrations in a viscous fluid. Original method for the force evaluation is presented based on analysis of experimental measurements of a logarithmic decrement of vibrations and relative variation in frequency of duralumin test specimens. The theoretical core of the method is based on the classical theory of bending beam oscillations and quasi-two dimensional model of interaction between a beam and a gas. Using the proposed method, extensive series of experiments for a wide range of oscillations parameters were carried out. The processing of the experimental data allowed to establish the global influence of the aerodynamic effects on beam oscillations and the local force characteristics of each cross-section of the beam in the form of universal functions of dimensionless amplitude and dimensionless frequency of oscillation. The obtained estimates of the drag and added mass forces showed a good correspondence with the available numerical and experimental data practically in the entire range of the investigated parameters.
Evaluation of ground motion scaling methods for analysis of structural systems
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.
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.
Effectiveness of Mindfulness-Based Group Therapy Compared to the Usual Opioid Dependence Treatment.
Imani, Saeed; Atef Vahid, Mohammad Kazem; Gharraee, Banafsheh; Noroozi, Alireza; Habibi, Mojtaba; Bowen, Sarah
2015-06-01
This study investigated the effectiveness of mindfulness-based group therapy (MBGT) compared to the usual opioid dependence treatment (TAU).Thirty outpatients meeting the DSM-IV-TR criteria for opioid dependence from Iranian National Center for Addiction Studies (INCAS) were randomly assigned into experimental (Mindfulness-Based Group Therapy) and control groups (the Usual Treatment).The experimental group undertook eight weeks of intervention, but the control group received the usual treatment according to the INCAS program. The Five Factor Mindfulness Questionnaire (FFMQ) and the Addiction Sevier Index (ASI) were administered at pre-treatment and post-treatment assessment periods. Thirteen patients from the experimental group and 15 from the control group completed post-test assessments. The results of MANCOVA revealed an increase in mean scores in observing, describing, acting with awareness, non-judging, non-reacting, and decrease in mean scores of alcohol and opium in MBGT patient group. The effectiveness of MBGT, compared to the usual treatment, was discussed in this paper as a selective protocol in the health care setting for substance use disorders.
Effectiveness of Mindfulness-Based Group Therapy Compared to the Usual Opioid Dependence Treatment
Imani, Saeed; Atef Vahid, Mohammad Kazem; Gharraee, Banafsheh; Noroozi, Alireza; Habibi, Mojtaba; Bowen, Sarah
2015-01-01
Objective: This study investigated the effectiveness of mindfulness-based group therapy (MBGT) compared to the usual opioid dependence treatment (TAU).Thirty outpatients meeting the DSM-IV-TR criteria for opioid dependence from Iranian National Center for Addiction Studies (INCAS) were randomly assigned into experimental (Mindfulness-Based Group Therapy) and control groups (the Usual Treatment).The experimental group undertook eight weeks of intervention, but the control group received the usual treatment according to the INCAS program. Methods: The Five Factor Mindfulness Questionnaire (FFMQ) and the Addiction Sevier Index (ASI) were administered at pre-treatment and post-treatment assessment periods. Thirteen patients from the experimental group and 15 from the control group completed post-test assessments. Results: The results of MANCOVA revealed an increase in mean scores in observing, describing, acting with awareness, non-judging, non-reacting, and decrease in mean scores of alcohol and opium in MBGT patient group. Conclusion: The effectiveness of MBGT, compared to the usual treatment, was discussed in this paper as a selective protocol in the health care setting for substance use disorders. PMID:26877751
Valente, Marco A. G.; Teixeira, Deiver A.; Azevedo, David L.; Feliciano, Gustavo T.; Benedetti, Assis V.; Fugivara, Cecílio S.
2017-01-01
The interaction of volatile corrosion inhibitors (VCI), caprylate salt derivatives from amines, with zinc metallic surfaces is assessed by density functional theory (DFT) computer simulations, electrochemical impedance (EIS) measurements and humid chamber tests. The results obtained by the different methods were compared, and linear correlations were obtained between theoretical and experimental data. The correlations between experimental and theoretical results showed that the molecular size is the determining factor in the inhibition efficiency. The models used and experimental results indicated that dicyclohexylamine caprylate is the most efficient inhibitor. PMID:28620602
Theoretical modeling and experimental analysis of solar still integrated with evacuated tubes
NASA Astrophysics Data System (ADS)
Panchal, Hitesh; Awasthi, Anuradha
2017-06-01
In this present research work, theoretical modeling of single slope, single basin solar still integrated with evacuated tubes has been performed based on energy balance equations. Major variables like water temperature, inner glass cover temperature and distillate output has been computed based on theoretical modeling. The experimental setup has been made from locally available materials and installed at Gujarat Power Engineering and Research Institute, Mehsana, Gujarat, India (23.5880°N, 72.3693°E) with 0.04 m depth during 6 months of time interval. From the series of experiments, it is found considerable increment in average distillate output of a solar still when integrated with evacuated tubes not only during daytime but also from night time. In all experimental cases, the correlation of coefficient (r) and root mean square percentage deviation of theoretical modeling and experimental study found good agreement with 0.97 < r < 0.98 and 10.22 < e < 38.4% respectively.
Prediction of Thermodynamic Equilibrium Temperature of Cu-Based Shape-Memory Smart Materials
NASA Astrophysics Data System (ADS)
Eskİl, Murat; Aldaş, Kemal; Özkul, İskender
2015-01-01
The thermodynamic equilibrium temperature ( T 0) is an important factor in the austenite and martensitic phases. In this study, the effects of alloying elements and heat treatments on T 0 temperature were investigated using Genetic Programming (GP) which has become one of the tools used in the study of condensed matter. Due to the changes in T 0, it is possible to analyze the changes in the entropy of the phase transitions. The data patterns of the GP formulation are based on well-established experimental results from the literature. The results of the GP-based formulation were compared with experimental results and found to be reliable with a very high correlation ( R 2 = 0.965 for training and R 2 = 0.952 for testing).
NASA Astrophysics Data System (ADS)
Cardone, Donatello; Sofia, Salvatore
2012-12-01
Metallic tie-rods are currently used in many historical buildings for absorbing the out-of-plane horizontal forces of arches, vaults and roof trusses, despite they exhibit several limitations under service and seismic conditions. In this paper, a post-tensioned system based on the superelastic properties of Ni-Ti shape memory alloys is proposed for improving the structural performances of traditional metallic tie-rods. First, the thermal behavior under service conditions is investigated based on the results of numerical and experimental studies. Subsequently, the seismic performances under strong earthquakes are verified trough a number of shaking table tests on a 1:4-scale timber roof truss model. The outcomes of these studies fully confirm the achievement of the design objectives of the proposed prototype device.
NASA Astrophysics Data System (ADS)
Sisodia, Mitali; Shukla, Abhishek; Pathak, Anirban
2017-12-01
A scheme for distributed quantum measurement that allows nondestructive or indirect Bell measurement was proposed by Gupta et al [1]. In the present work, Gupta et al.'s scheme is experimentally realized using the five-qubit super-conductivity-based quantum computer, which has been recently placed in cloud by IBM Corporation. The experiment confirmed that the Bell state can be constructed and measured in a nondestructive manner with a reasonably high fidelity. A comparison of the outcomes of this study and the results obtained earlier in an NMR-based experiment (Samal et al. (2010) [10]) has also been performed. The study indicates that to make a scalable SQUID-based quantum computer, errors introduced by the gates (in the present technology) have to be reduced considerably.
Opening School-Based Health Centers in a Rural Setting: Effects on Emergency Department Use
ERIC Educational Resources Information Center
Schwartz, Katherine E.; Monie, Daphne; Scribani, Melissa B.; Krupa, Nicole L.; Jenkins, Paul; Leinhart, August; Kjolhede, Chris L.
2016-01-01
Background: Previous studies of urban school-based health centers (SBHCs) have shown that SBHCs decrease emergency department (ED) utilization. This study seeks to evaluate the effect of SBHCs on ED utilization in a rural setting. Methods: This retrospective, controlled, quasi-experimental study used an ED patient data set from the Bassett…
ERIC Educational Resources Information Center
Günter, Tugçe; Alpat, Sibel Kilinç
2017-01-01
This study investigates the effects of problem-based learning (PBL) on students' academic achievements in studying "Electrochemistry" within a course on Analytical Chemistry. The research was of a pretest-posttest control group quasi-experimental design and it was conducted with second year students in the Chemistry Teaching Program at…
NASA Astrophysics Data System (ADS)
khawaldeh, Salem A. Al
2013-07-01
Background and purpose: The purpose of this study was to investigate the comparative effects of a prediction/discussion-based learning cycle (HPD-LC), conceptual change text (CCT) and traditional instruction on 10th grade students' understanding of genetics concepts. Sample: Participants were 112 10th basic grade male students in three classes of the same school located in an urban area. The three classes taught by the same biology teacher were randomly assigned as a prediction/discussion-based learning cycle class (n = 39), conceptual change text class (n = 37) and traditional class (n = 36). Design and method: A quasi-experimental research design of pre-test-post-test non-equivalent control group was adopted. Participants completed the Genetics Concept Test as pre-test-post-test, to examine the effects of instructional strategies on their genetics understanding. Pre-test scores and Test of Logical Thinking scores were used as covariates. Results: The analysis of covariance showed a statistically significant difference between the experimental and control groups in the favor of experimental groups after treatment. However, no statistically significant difference between the experimental groups (HPD-LC versus CCT instruction) was found. Conclusions: Overall, the findings of this study support the use of the prediction/discussion-based learning cycle and conceptual change text in both research and teaching. The findings may be useful for improving classroom practices in teaching science concepts and for the development of suitable materials promoting students' understanding of science.
Computational Insights into the O2-evolving complex of photosystem II
Sproviero, Eduardo M.; McEvoy, James P.; Gascón, José A.; Brudvig, Gary W.; Batista, Victor S.
2009-01-01
Mechanistic investigations of the water-splitting reaction of the oxygen-evolving complex (OEC) of photosystem II (PSII) are fundamentally informed by structural studies. Many physical techniques have provided important insights into the OEC structure and function, including X-ray diffraction (XRD) and extended X-ray absorption fine structure (EXAFS) spectroscopy as well as mass spectrometry (MS), electron paramagnetic resonance (EPR) spectroscopy and Fourier transform infrared spectroscopy applied in conjunction with mutagenesis studies. However, experimental studies have yet to yield consensus as to the exact configuration of the catalytic metal cluster and its ligation scheme. Computational modeling studies, including density functional (DFT) theory combined with quantum mechanics/molecular mechanics (QM/MM) hybrid methods for explicitly including the influence of the surrounding protein, have proposed chemically satisfactory models of the fully ligated OEC within PSII that are maximally consistent with experimental results. The inorganic core of these models is similar to the crystallographic model upon which they were based but comprises important modifications due to structural refinement, hydration and proteinaceous ligation which improve agreement with a wide range of experimental data. The computational models are useful for rationalizing spectroscopic and crystallographic results and for building a complete structure-based mechanism of water-splitting in PSII as described by the intermediate oxidation states of the OEC. This review summarizes these recent advances in QM/MM modeling of PSII within the context of recent experimental studies. PMID:18483777
Rowe, Rachel K.; Harrison, Jordan L.; Thomas, Theresa C.; Pauly, James R.; Adelson, P. David; Lifshitz, Jonathan
2013-01-01
The use of animal modeling in traumatic brain injury (TBI) research is justified by the lack of sufficiently comprehensive in vitro and computer modeling that incorporates all components of the neurovascular unit. Valid animal modeling of TBI requires accurate replication of both the mechanical forces and secondary injury conditions observed in human patients. Regulatory requirements for animal modeling emphasize the administration of appropriate anesthetics and analgesics unless withholding these drugs is scientifically justified. The objective of this review is to present scientific justification for standardizing the use of anesthetics and analgesics, within a study, when modeling TBI in order to preserve study validity. Evidence for the interference of anesthetics and analgesics in the natural course of brain injury calls for consistent consideration of pain management regimens when conducting TBI research. Anesthetics administered at the time of or shortly after induction of brain injury can alter cognitive, motor, and histological outcomes following TBI. A consistent anesthesia protocol based on experimental objectives within each individual study is imperative when conducting TBI studies to control for the confounding effects of anesthesia on outcome parameters. Experimental studies that replicate the clinical condition are essential to gain further understanding and evaluate possible treatments for TBI. However, with animal models of TBI it is essential that investigators assure a uniform drug delivery protocol that minimizes confounding variables, while minimizing pain and suffering. PMID:23877609
Frank, James A.; Parsons, Polly E.; Matthay, Michael A.
2009-01-01
For patients with acute lung injury, positive pressure mechanical ventilation is life saving. However, considerable experimental and clinical data have demonstrated that how clinicians set the tidal volume, positive end-expiratory pressure, and plateau airway pressure influences lung injury severity and patient outcomes including mortality. In order to better identify ventilator-associated lung injury (VALI), clinical investigators have sought to measure blood-borne and airspace biological markers of VALI. At the same time, several laboratory-based studies have focused on biological markers of inflammation and organ injury in experimental models in order to clarify the mechanisms of ventilator-induced lung injury (VILI) and VALI. This review summarizes data on biological markers of VALI and VILI from both clinical and experimental studies with an emphasis on markers identified in patients and in the experimental setting. This analysis suggests that measurement of some of these biological markers may be of value in diagnosing VALI and in understanding its pathogenesis. PMID:17167015
Xiao, Deli; Zhang, Chan; He, Jia; Zeng, Rong; Chen, Rong; He, Hua
2016-01-01
Simple, accurate and high-throughput pretreatment method would facilitate large-scale studies of trace analysis in complex samples. Magnetic mixed hemimicelles solid-phase extraction has the power to become a key pretreatment method in biological, environmental and clinical research. However, lacking of experimental predictability and unsharpness of extraction mechanism limit the development of this promising method. Herein, this work tries to establish theoretical-based experimental designs for extraction of trace analytes from complex samples using magnetic mixed hemimicelles solid-phase extraction. We selected three categories and six sub-types of compounds for systematic comparative study of extraction mechanism, and comprehensively illustrated the roles of different force (hydrophobic interaction, π-π stacking interactions, hydrogen-bonding interaction, electrostatic interaction) for the first time. What’s more, the application guidelines for supporting materials, surfactants and sample matrix were also summarized. The extraction mechanism and platform established in the study render its future promising for foreseeable and efficient pretreatment under theoretical based experimental design for trace analytes from environmental, biological and clinical samples. PMID:27924944
Host-guest interaction of ZnBDC-MOF + doxorubicin: A theoretical and experimental study
NASA Astrophysics Data System (ADS)
Vasconcelos, Iane B.; Wanderley, Kaline A.; Rodrigues, Nailton M.; da Costa, Nivan B.; Freire, Ricardo O.; Junior, Severino A.
2017-03-01
The incorporation of drugs in biodegradable polymeric particles is one of many processes that controllably and significantly increase their release and action. In this paper, we describe the synthesis and physicochemical characterization of ZnBDC-MOF + doxorubicin (DOXO@ZnBDC) and the system's effectiveness in the sustained release of the drug doxorubicin. An experimental and theoretical study is presented of the interaction between the [Zn(BDC)(H2O)2]n MOF and the drug doxorubicin (DOXO). The synthesis was characterized by elemental analysis and X-ray powder diffraction (XRPD). The experimental incorporation was accomplished and analyzed by Fourier transform infrared spectroscopy (FTIR), XRPD and UV-Vis (ultraviolet-visible) spectrophotometry. Based on an analysis of the doxorubicin release profile, our results suggest that the drug delivery system showed slower release than other systems under development. Studies of cytotoxicity by the MTT method showed good results for the system developed with antineoplastic doxorubicin, and together with the other results of this study, suggest the successful development of a MOF-based drug delivery system.
Zhang, Fan; Liu, Ming; Harper, Stephen; Lee, Michael; Huang, He
2014-07-22
To enable intuitive operation of powered artificial legs, an interface between user and prosthesis that can recognize the user's movement intent is desired. A novel neural-machine interface (NMI) based on neuromuscular-mechanical fusion developed in our previous study has demonstrated a great potential to accurately identify the intended movement of transfemoral amputees. However, this interface has not yet been integrated with a powered prosthetic leg for true neural control. This study aimed to report (1) a flexible platform to implement and optimize neural control of powered lower limb prosthesis and (2) an experimental setup and protocol to evaluate neural prosthesis control on patients with lower limb amputations. First a platform based on a PC and a visual programming environment were developed to implement the prosthesis control algorithms, including NMI training algorithm, NMI online testing algorithm, and intrinsic control algorithm. To demonstrate the function of this platform, in this study the NMI based on neuromuscular-mechanical fusion was hierarchically integrated with intrinsic control of a prototypical transfemoral prosthesis. One patient with a unilateral transfemoral amputation was recruited to evaluate our implemented neural controller when performing activities, such as standing, level-ground walking, ramp ascent, and ramp descent continuously in the laboratory. A novel experimental setup and protocol were developed in order to test the new prosthesis control safely and efficiently. The presented proof-of-concept platform and experimental setup and protocol could aid the future development and application of neurally-controlled powered artificial legs.
Electrical conductivity modeling and experimental study of densely packed SWCNT networks.
Jack, D A; Yeh, C-S; Liang, Z; Li, S; Park, J G; Fielding, J C
2010-05-14
Single-walled carbon nanotube (SWCNT) networks have become a subject of interest due to their ability to support structural, thermal and electrical loadings, but to date their application has been hindered due, in large part, to the inability to model macroscopic responses in an industrial product with any reasonable confidence. This paper seeks to address the relationship between macroscale electrical conductivity and the nanostructure of a dense network composed of SWCNTs and presents a uniquely formulated physics-based computational model for electrical conductivity predictions. The proposed model incorporates physics-based stochastic parameters for the individual nanotubes to construct the nanostructure such as: an experimentally obtained orientation distribution function, experimentally derived length and diameter distributions, and assumed distributions of chirality and registry of individual CNTs. Case studies are presented to investigate the relationship between macroscale conductivity and nanostructured variations in the bulk stochastic length, diameter and orientation distributions. Simulation results correspond nicely with those available in the literature for case studies of conductivity versus length and conductivity versus diameter. In addition, predictions for the increasing anisotropy of the bulk conductivity as a function of the tube orientation distribution are in reasonable agreement with our experimental results. Examples are presented to demonstrate the importance of incorporating various stochastic characteristics in bulk conductivity predictions. Finally, a design consideration for industrial applications is discussed based on localized network power emission considerations and may lend insight to the design engineer to better predict network failure under high current loading applications.
Influence of coal slurry particle composition on pipeline hydraulic transportation behavior
NASA Astrophysics Data System (ADS)
Li-an, Zhao; Ronghuan, Cai; Tieli, Wang
2018-02-01
Acting as a new type of energy transportation mode, the coal pipeline hydraulic transmission can reduce the energy transportation cost and the fly ash pollution of the conventional coal transportation. In this study, the effect of average velocity, particle size and pumping time on particle composition of coal particles during hydraulic conveying was investigated by ring tube test. Meanwhile, the effects of particle composition change on slurry viscosity, transmission resistance and critical sedimentation velocity were studied based on the experimental data. The experimental and theoretical analysis indicate that the alter of slurry particle composition can lead to the change of viscosity, resistance and critical velocity of slurry. Moreover, based on the previous studies, the critical velocity calculation model of coal slurry is proposed.
An empirically-based model for the lift coefficients of twisted airfoils with leading-edge tubercles
NASA Astrophysics Data System (ADS)
Ni, Zao; Su, Tsung-chow; Dhanak, Manhar
2018-04-01
Experimental data for untwisted airfoils are utilized to propose a model for predicting the lift coefficients of twisted airfoils with leading-edge tubercles. The effectiveness of the empirical model is verified through comparison with results of a corresponding computational fluid-dynamic (CFD) study. The CFD study is carried out for both twisted and untwisted airfoils with tubercles, the latter shown to compare well with available experimental data. Lift coefficients of twisted airfoils predicted from the proposed empirically-based model match well with the corresponding coefficients determined using the verified CFD study. Flow details obtained from the latter provide better insight into the underlying mechanism and behavior at stall of twisted airfoils with leading edge tubercles.
Park, Sunhee; Weaver, Terri E; Romer, Daniel
2009-04-01
This study examined factors affecting the transition from experimental smoking at baseline to two types of daily smoking, temporary daily smoking, and continued daily smoking, at 1-year follow-up. This study analyzed data from the National Longitudinal Study of Adolescent Health (n = 4,903 U.S. adolescents). Baseline predictors were selected based on Problem Behavior Theory. Important problem behavior theory-related predictors of smoking were the number of friends who smoke, academic performance, and alcohol, marijuana, and other illicit drug use. Other significant predictors were age, gender, race, depression, perceived general health, and cigarette availability at home. To prevent teens from progressing to daily smoking, nursing professionals should consider multifaceted factors based on multiple theories.
Standard of reporting animal-based experimental research in Indian Journal of Pharmacology.
Aiman, Umme; Rahman, Syed Ziaur
2015-01-01
The objective of present study was to survey and determine the reporting standards of animal studies published during three years from 2012 to 2014 in the Indian Journal of Pharmacology (IJP). All issues of IJP published in the year 2012, 2013 and 2014 were reviewed to identify animal studies. Each animal study was searched for 15 parameters specifically designed to review standards of animal experimentation and research methodology. All published studies had clearly defined aims and objectives while a statement on ethical clearance about the study protocol was provided in 97% of papers. Information about animal strain and sex was given in 91.8% and 90% of papers respectively. Age of experimental animals was mentioned by 44.4% papers while source of animals was given in 50.8% papers. Randomization was reported by 37.4% while 9.9% studies reported blinding. Only 3.5% studies mentioned any limitations of their work. Present study demonstrates relatively good reporting standards in animal studies published in IJP. The items which need to be improved are randomization, blinding, sample size calculation, stating the limitations of study, sources of support and conflict of interest. The knowledge shared in the present paper could be used for better reporting of animal based experiments.
Positive psychology group intervention for breast cancer patients: a randomised trial.
Victoria Cerezo, M; Ortiz-Tallo, Margarita; Cardenal, Violeta; De La Torre-Luque, Alejandro
2014-08-01
This study assessed the effects of a psychological group intervention based on positive psychology in women with breast cancer. 175 women were randomly assigned either to an experimental group, receiving the 14-session intervention (n = 87), or to a wait list group (n = 88) that did not receive any type of intervention. For treatment, a group intervention was applied, based on improving psychological strengths and enhancing positive psychology-based styles of coping. Strength-related outcomes, self-esteem, well-being, and happiness were assessed before and after the intervention. The experimental group showed higher scores on all of the study variables after the intervention. Participants reported improved self-esteem, emotional intelligence-related abilities, resilience, and optimism, as well as positive affectivity, well-being, and happiness. The results show a beneficial effect of this psychological intervention based on positive psychology on female breast cancer patients' psychological health.
Flexible manipulator control experiments and analysis
NASA Technical Reports Server (NTRS)
Yurkovich, S.; Ozguner, U.; Tzes, A.; Kotnik, P. T.
1987-01-01
Modeling and control design for flexible manipulators, both from an experimental and analytical viewpoint, are described. From the application perspective, an ongoing effort within the laboratory environment at the Ohio State University, where experimentation on a single link flexible arm is underway is described. Several unique features of this study are described here. First, the manipulator arm is slewed by a direct drive dc motor and has a rigid counterbalance appendage. Current experimentation is from two viewpoints: (1) rigid body slewing and vibration control via actuation with the hub motor, and (2) vibration suppression through the use of structure-mounted proof-mass actuation at the tip. Such an application to manipulator control is of interest particularly in design of space-based telerobotic control systems, but has received little attention to date. From an analytical viewpoint, parameter estimation techniques within the closed-loop for self-tuning adaptive control approaches are discussed. Also introduced is a control approach based on output feedback and frequency weighting to counteract effects of spillover in reduced-order model design. A model of the flexible manipulator based on experimental measurements is evaluated for such estimation and control approaches.
Experimental setups for FEL-based four-wave mixing experiments at FERMI
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bencivenga, Filippo; Zangrando, Marco; Svetina, Cristian
2016-01-01
The recent advent of free-electron laser (FEL) sources is driving the scientific community to extend table-top laser research to shorter wavelengths adding elemental selectivity and chemical state specificity. Both a compact setup (mini-TIMER) and a separate instrument (EIS-TIMER) dedicated to four-wave-mixing (FWM) experiments has been designed and constructed, to be operated as a branch of the Elastic and Inelastic Scattering beamline: EIS. The FWM experiments that are planned at EIS-TIMER are based on the transient grating approach, where two crossed FEL pulses create a controlled modulation of the sample excitations while a third time-delayed pulse is used to monitor themore » dynamics of the excited state. This manuscript describes such experimental facilities, showing the preliminary results of the commissioning of the EIS-TIMER beamline, and discusses original experimental strategies being developed to study the dynamics of matter at the fs–nm time–length scales. In the near future such experimental tools will allow more sophisticated FEL-based FWM applications, that also include the use of multiple and multi-color FEL pulses.« less
Experimental setups for FEL-based four-wave mixing experiments at FERMI
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bencivenga, Filippo; Zangrando, Marco; Svetina, Cristian
The recent advent of free-electron laser (FEL) sources is driving the scientific community to extend table-top laser research to shorter wavelengths adding elemental selectivity and chemical state specificity. Both a compact setup (mini-TIMER) and a separate instrument (EIS-TIMER) dedicated to four-wave-mixing (FWM) experiments has been designed and constructed, to be operated as a branch of the Elastic and Inelastic Scattering beamline: EIS. The FWM experiments that are planned at EIS-TIMER are based on the transient grating approach, where two crossed FEL pulses create a controlled modulation of the sample excitations while a third time-delayed pulse is used to monitor themore » dynamics of the excited state. This manuscript describes such experimental facilities, showing the preliminary results of the commissioning of the EIS-TIMER beamline, and discusses original experimental strategies being developed to study the dynamics of matter at the fs–nm time–length scales. In the near future such experimental tools will allow more sophisticated FEL-based FWM applications, that also include the use of multiple and multi-color FEL pulses.« less
NASA Astrophysics Data System (ADS)
Wang, Zengwei; Zhu, Ping; Liu, Zhao
2018-01-01
A generalized method for predicting the decoupled transfer functions based on in-situ transfer functions is proposed. The method allows predicting the decoupled transfer functions using coupled transfer functions, without disassembling the system. Two ways to derive relationships between the decoupled and coupled transfer functions are presented. Issues related to immeasurability of coupled transfer functions are also discussed. The proposed method is validated by numerical and experimental case studies.
Experimental Study of Ultrasound Contrast Agent Mediated Heat Transfer for Therapeutic Applications
NASA Astrophysics Data System (ADS)
Razansky, D.; Adam, D. R.; Einziger, P. D.
2006-05-01
Ultrasound Contrast Agents (UCA) have been recently suggested as efficient enhancers of ultrasonic power deposition in tissue. The ultrasonic energy absorption by UCA, considered as disadvantageous in diagnostic imaging, might be valuable in therapeutic applications such as targeted hyperthermia or ablation treatments. The current study, based on theoretical predictions, was designed to experimentally measure the dissipation and heating effects of encapsulated UCA (Optison™) in a well-controlled and calibrated environment.
NASA Technical Reports Server (NTRS)
Neudeck, Philip G.; Spry, David J.; Chen, Liangyu
2015-01-01
This work reports a theoretical and experimental study of 4H-SiC JFET threshold voltage as a function of substrate body bias, device position on the wafer, and temperature from 25 C (298K) to 500 C (773K). Based on these results, an alternative approach to SPICE circuit simulation of body effect for SiC JFETs is proposed.
Ionic polymer-metal composite torsional sensor: physics-based modeling and experimental validation
NASA Astrophysics Data System (ADS)
Aidi Sharif, Montassar; Lei, Hong; Khalid Al-Rubaiai, Mohammed; Tan, Xiaobo
2018-07-01
Ionic polymer-metal composites (IPMCs) have intrinsic sensing and actuation properties. Typical IPMC sensors are in the shape of beams and only respond to stimuli acting along beam-bending directions. Rod or tube-shaped IPMCs have been explored as omnidirectional bending actuators or sensors. In this paper, physics-based modeling is studied for a tubular IPMC sensor under pure torsional stimulus. The Poisson–Nernst–Planck model is used to describe the fundamental physics within the IPMC, where it is hypothesized that the anion concentration is coupled to the sum of shear strains induced by the torsional stimulus. Finite element simulation is conducted to solve for the torsional sensing response, where some of the key parameters are identified based on experimental measurements using an artificial neural network. Additional experimental results suggest that the proposed model is able to capture the torsional sensing dynamics for different amplitudes and rates of the torsional stimulus.
Analytical and experimental study of axisymmetric truncated plug nozzle flow fields
NASA Technical Reports Server (NTRS)
Muller, T. J.; Sule, W. P.; Fanning, A. E.; Giel, T. V.; Galanga, F. L.
1972-01-01
Experimental and analytical investigation of the flow field and base pressure of internal-external-expansion truncated plug nozzles are discussed. Experimental results for two axisymmetric, conical plug-cylindrical shroud, truncated plug nozzles are presented for both open and closed wake operations. These results include extensive optical and pressure data covering nozzle flow field and base pressure characteristics, diffuser effects, lip shock strength, Mach disc behaviour, and the recompression and reverse flow regions. Transonic experiments for a special planar transonic section are presented. An extension of the analytical method of Hall and Mueller to include the internal shock wave from the shroud exit is presented for closed wake operation. Results of this analysis include effects on the flow field and base pressure of ambient pressure ratio, nozzle geometry, and the ratio of specific heats. Static thrust is presented as a function of ambient pressure ratio and nozzle geometry. A new transonic solution method is also presented.
Experimental Study of Damage Evolution in Circular Stirrup-Confined Concrete
Li, Zuohua; Peng, Zhihan; Teng, Jun; Wang, Ying
2016-01-01
This paper presents an experimental study on circular stirrup-confined concrete specimens under uniaxial and monotonic load. The effects of stirrup volume ratio, stirrup yield strength and concrete strength on damage evolution of stirrup-confined concrete were investigated. The experimental results showed that the strength and ductility of concrete are improved by appropriate arrangement of the stirrup confinement. Firstly, the concrete damage evolution can be relatively restrained with the increase of the stirrup volume ratio. Secondly, higher stirrup yield strength usually causes larger confining pressures and slower concrete damage evolution. In contrast, higher concrete strength leads to higher brittleness, which accelerates the concrete damage evolution. A plastic strain expression is obtained through curve fitting, and a damage evolution equation for circular stirrup-confined concrete is proposed by introducing a confinement factor (C) based on the experimental data. The comparison results demonstrate that the proposed damage evolution model can accurately describe the experimental results. PMID:28773402
Experimental Study of Damage Evolution in Circular Stirrup-Confined Concrete.
Li, Zuohua; Peng, Zhihan; Teng, Jun; Wang, Ying
2016-04-08
This paper presents an experimental study on circular stirrup-confined concrete specimens under uniaxial and monotonic load. The effects of stirrup volume ratio, stirrup yield strength and concrete strength on damage evolution of stirrup-confined concrete were investigated. The experimental results showed that the strength and ductility of concrete are improved by appropriate arrangement of the stirrup confinement. Firstly, the concrete damage evolution can be relatively restrained with the increase of the stirrup volume ratio. Secondly, higher stirrup yield strength usually causes larger confining pressures and slower concrete damage evolution. In contrast, higher concrete strength leads to higher brittleness, which accelerates the concrete damage evolution. A plastic strain expression is obtained through curve fitting, and a damage evolution equation for circular stirrup-confined concrete is proposed by introducing a confinement factor ( C ) based on the experimental data. The comparison results demonstrate that the proposed damage evolution model can accurately describe the experimental results.
Numerical and experimental study on buckling and postbuckling behavior of cracked cylindrical shells
NASA Astrophysics Data System (ADS)
Saemi, J.; Sedighi, M.; Shariati, M.
2015-09-01
The effect of crack on load-bearing capacity and buckling behavior of cylindrical shells is an essential consideration in their design. In this paper, experimental and numerical buckling analysis of steel cylindrical shells of various lengths and diameters with cracks have been studied using the finite element method, and the effect of crack position, crack orientation and the crack length-to-cylindrical shell perimeter ( λ = a/(2 πr)) and shell length-to-diameter ( L/ D) ratios on the buckling and post-buckling behavior of cylindrical shells has been investigated. For several specimens, buckling test was performed using an INSTRON 8802 servo hydraulic machine, and the results of experimental tests were compared to numerical results. A very good correlation was observed between numerical simulation and experimental results. Finally, based on the experimental and numerical results, sensitivity of the buckling load to the shell length, crack length and orientation has also been investigated.
Correlation between Sleep Duration and Risk of Stroke.
Patyar, Sazal; Patyar, Rakesh Raman
2015-05-01
Modern lifestyle and job requirements have changed the sleep habits of most of the adult population. Various population-based studies have associated an increase in mortality with either shortened sleep or long sleep duration. Thus a U-shaped relationship between sleep duration and all-cause mortality in both men and women has been suggested. Several studies have found an association between sleep duration and risk of cardiovascular diseases also. Efforts to understand the etiology of stroke have indicated an association between sleep and stroke too. Obstructive sleep apnea, a sleep-related disorder, has been reported to significantly increase the risk of stroke. Moreover, many studies have shown that both short and long sleep durations are related to increased likelihood of diabetes and hypertension, which themselves are risk factors for stroke. Therefore, this review focuses on the correlation between sleep duration and risk of stroke based on the experimental and epidemiologic studies. Although a few experimental studies have reported that partial sleep deprivation may reduce stroke incidence and severity, yet, most experimental and observational studies have indicated a strong association between short/long sleep durations and higher risk of stroke. Copyright © 2015 National Stroke Association. Published by Elsevier Inc. All rights reserved.
Model based manipulator control
NASA Technical Reports Server (NTRS)
Petrosky, Lyman J.; Oppenheim, Irving J.
1989-01-01
The feasibility of using model based control (MBC) for robotic manipulators was investigated. A double inverted pendulum system was constructed as the experimental system for a general study of dynamically stable manipulation. The original interest in dynamically stable systems was driven by the objective of high vertical reach (balancing), and the planning of inertially favorable trajectories for force and payload demands. The model-based control approach is described and the results of experimental tests are summarized. Results directly demonstrate that MBC can provide stable control at all speeds of operation and support operations requiring dynamic stability such as balancing. The application of MBC to systems with flexible links is also discussed.
Computational method for multi-modal microscopy based on transport of intensity equation
NASA Astrophysics Data System (ADS)
Li, Jiaji; Chen, Qian; Sun, Jiasong; Zhang, Jialin; Zuo, Chao
2017-02-01
In this paper, we develop the requisite theory to describe a hybrid virtual-physical multi-modal imaging system which yields quantitative phase, Zernike phase contrast, differential interference contrast (DIC), and light field moment imaging simultaneously based on transport of intensity equation(TIE). We then give the experimental demonstration of these ideas by time-lapse imaging of live HeLa cell mitosis. Experimental results verify that a tunable lens based TIE system, combined with the appropriate post-processing algorithm, can achieve a variety of promising imaging modalities in parallel with the quantitative phase images for the dynamic study of cellular processes.
Physical Modeling of the Polyfrequency Filter-Compensating Device Based on the Capacitor-Coil
NASA Astrophysics Data System (ADS)
Butyrin, P. A.; Gusev, G. G.; Mikheev, D. V.; Shakirzianov, F. N.
2017-12-01
The paper presents the results of physical modeling and experimental study of the frequency characteristics of the polyfrequency filter-compensating device (PFCD) based on a capacitor-coil. The amplitude- frequency and phase-frequency characteristics of the physical PFCD model were constructed and its equivalent parameters were identified. The feasibility of a PFCD in the form of a single technical device with high technical and economic characteristics was experimentally proven. In the paper, recommendations for practical applications of the capacitor-coil-based PFCD are made and the advantages of the device over known standard passive filter-compensating devices are evaluated.
1981-08-01
electro - optic effect is investigated both theoretically and experimentally. The theoretical approach is based upon W.A. Harrison’s ’Bond-Orbital Model’. The separate electronic and lattice contributions to the second-order, electro - optic susceptibility are examined within the context of this model and formulae which can accommodate any crystal structure are presented. In addition, a method for estimating the lattice response to a low frequency (dc) electric field is outlined. Finally, experimental measurements of the electro -
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bonior, Jason D; Hu, Zhen; Guo, Terry N.
This letter presents an experimental demonstration of software-defined-radio-based wireless tomography using computer-hosted radio devices called Universal Software Radio Peripheral (USRP). This experimental brief follows our vision and previous theoretical study of wireless tomography that combines wireless communication and RF tomography to provide a novel approach to remote sensing. Automatic data acquisition is performed inside an RF anechoic chamber. Semidefinite relaxation is used for phase retrieval, and the Born iterative method is utilized for imaging the target. Experimental results are presented, validating our vision of wireless tomography.
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.
School-based obesity prevention programs: an evidence-based review.
Kropski, Jonathan A; Keckley, Paul H; Jensen, Gordon L
2008-05-01
This review seeks to examine the effectiveness of school-based programs for reducing childhood overweight or obesity. A systematic review of the research literature published since 1990 was conducted to identify experimental or quasi-experimental school-based curricular or environmental preventive interventions, with evaluation>or=6 months after baseline, which reported outcomes in terms of a measure of overweight. Fourteen studies were identified, including one involving a nutrition-only program, two physical activity promotion interventions and eleven studies combining nutrition and physical activity components. Most studies (n=10) offered weak (grade 2) quality evidence. One study offered strong (grade 4) evidence reducing the odds ratio for overweight in girls only, while four grade 2 studies reported significant improvements in BMI or at-risk-for overweight or overweight prevalence in boys, girls, or both. Twelve studies reported significant improvement in at least one measure of dietary intake, physical activity, and/or sedentary behavior. Our ability to draw strong conclusions as to the efficacy of school-based obesity prevention programs is limited by the small number of published studies and by methodological concerns. Qualitative analysis suggests programs grounded in social learning may be more appropriate for girls, while structural and environmental interventions enabling physical activity may be more effective for boys. High-quality evaluation protocols should be considered essential components of future programs.
Structural properties of lead-lithium alloys
NASA Astrophysics Data System (ADS)
Khambholja, S. G.; Satikunvar, D. D.; Abhishek, Agraj; Thakore, B. Y.
2018-05-01
Lead-Lihtium alloys have found large number of applications as liquid metal coolants in nuclear reactors. Large number of experimental work is reported for this system. However, complete theoretical description is still rare. In this scenario, we in the present work report the study of ground state properties of Lead-Lithium system. The present study is performed using plane wave pseudopotential density functional theory as implemented in Quantum ESPRESSO package. The theoretical findings are in agreement with previously reported experimental data. Some conclusions are drawn based on present study, which will be helpful for a comprehensive study.
Strong anisotropy effect in an iron-based superconductor CaFe0.882Co0.118AsF
NASA Astrophysics Data System (ADS)
Ma, Yonghui; Ji, Qiucheng; Hu, Kangkang; Gao, Bo; Li, Wei; Mu, Gang; Xie, Xiaoming
2017-07-01
The anisotropy of iron-based superconductors is much smaller than that of the cuprates and that predicted by theoretical calculations. A credible understanding for this experimental fact is still lacking up to now. Here we experimentally study the magnetic-field-angle dependence of electronic resistivity in the superconducting phase of an iron-based superconductor CaFe{}0.882Co{}0.118AsF, and find the strongest anisotropy effect of the upper critical field among the iron-based superconductors based on the framework of Ginzburg-Landau theory. The evidence of the energy band structure and charge density distribution from electronic structure calculations demonstrates that the observed strong anisotropic effect mainly comes from the strong ionic bonding in between the ions of Ca2+ and F-, which weakens the interlayer coupling between the layers of FeAs and CaF. This finding provides a significant insight into the nature of the experimentally-observed strong anisotropic effect of electronic resistivity, and also paves the way for designing exotic two-dimensional artificial unconventional superconductors in the future.
Analysis of pre-service physics teacher skills designing simple physics experiments based technology
NASA Astrophysics Data System (ADS)
Susilawati; Huda, C.; Kurniawan, W.; Masturi; Khoiri, N.
2018-03-01
Pre-service physics teacher skill in designing simple experiment set is very important in adding understanding of student concept and practicing scientific skill in laboratory. This study describes the skills of physics students in designing simple experiments based technologicall. The experimental design stages include simple tool design and sensor modification. The research method used is descriptive method with the number of research samples 25 students and 5 variations of simple physics experimental design. Based on the results of interviews and observations obtained the results of pre-service physics teacher skill analysis in designing simple experimental physics charged technology is good. Based on observation result, pre-service physics teacher skill in designing simple experiment is good while modification and sensor application are still not good. This suggests that pre-service physics teacher still need a lot of practice and do experiments in designing physics experiments using sensor modifications. Based on the interview result, it is found that students have high enough motivation to perform laboratory activities actively and students have high curiosity to be skilled at making simple practicum tool for physics experiment.
NASA Astrophysics Data System (ADS)
Saidi, B.; Giraud-Moreau, L.; Cherouat, A.; Nasri, R.
2017-09-01
AINSI 304L stainless steel sheets are commonly formed into a variety of shapes for applications in the industrial, architectural, transportation and automobile fields, it’s also used for manufacturing of denture base. In the field of dentistry, there is a need for personalized devises that are custom made for the patient. The single point incremental forming process is highly promising in this area for manufacturing of denture base. The single point incremental forming process (ISF) is an emerging process based on the use of a spherical tool, which is moved along CNC controlled tool path. One of the major advantages of this process is the ability to program several punch trajectories on the same machine in order to obtain different shapes. Several applications of this process exist in the medical field for the manufacturing of personalized titanium prosthesis (cranial plate, knee prosthesis...) due to the need of product customization to each patient. The objective of this paper is to study the incremental forming of AISI 304L stainless steel sheets for future applications in the dentistry field. During the incremental forming process, considerable forces can occur. The control of the forming force is particularly important to ensure the safe use of the CNC milling machine and preserve the tooling and machinery. In this paper, the effect of four different process parameters on the maximum force is studied. The proposed approach consists in using an experimental design based on experimental results. An analysis of variance was conducted with ANOVA to find the input parameters allowing to minimize the maximum forming force. A numerical simulation of the incremental forming process is performed with the optimal input process parameters. Numerical results are compared with the experimental ones.
Dufour, Barbara; Praud, Anne
2017-01-01
Understanding the factors leading each stakeholder to participate in an experimental trial is a key element for improving trial set-up and for identifying selection bias in statistical analyses. An experimental protocol, validated by the European Commission, was developed in France to assess the ability of the gamma-interferon test in terms of accuracy to replace the second intradermal skin test in cases of suspected bovine tuberculosis. Implemented between 2013 and 2015, this experimental trial was based on voluntary participation. To determine and understand the motivation or reluctance of farmers to take part in this trial, we carried out a sociological survey in France. Our study was based on semi-structured interviews with the farmers and other stakeholders involved. The analysis of findings demonstrated that shortening the lock-up period during tuberculosis suspicion, following the use of a gamma-interferon test, was an important aim and a genuine challenge for the animal health stakeholders. However, some farmers did not wish to continue the trial because it could potentially have drastic consequences for them. Moreover, misunderstandings and confusion concerning the objectives and consequences of the trial led stakeholders to reject it forcefully. Based on our results, we offer some recommendations: clear and appropriate communication tools should be prepared to explain the protocol and its aims. In addition, these types of animal health trials should be designed with the stakeholders’ interests in mind. This study provides a better understanding of farmer motivations and stakeholder influences on trial participation and outcomes. The findings can be used to help design trials so that they promote participation by farmers and by all animal health stakeholders in general. PMID:28973018
DOE Office of Scientific and Technical Information (OSTI.GOV)
Andronov, V.A.; Zhidov, I.G.; Meskov, E.E.
The report presents the basic results of some calculations, theoretical and experimental efforts in the study of Rayleigh-Taylor, Kelvin-Helmholtz, Richtmyer-Meshkov instabilities and the turbulent mixing which is caused by their evolution. Since the late forties the VNIIEF has been conducting these investigations. This report is based on the data which were published in different times in Russian and foreign journals. The first part of the report deals with calculations an theoretical techniques for the description of hydrodynamic instabilities applied currently, as well as with the results of several individual problems and their comparison with the experiment. These methods can bemore » divided into two types: direct numerical simulation methods and phenomenological methods. The first type includes the regular 2D and 3D gasdynamical techniques as well as the techniques based on small perturbation approximation and on incompressible liquid approximation. The second type comprises the techniques based on various phenomenological turbulence models. The second part of the report describes the experimental methods and cites the experimental results of Rayleigh-Taylor and Richtmyer-Meskov instability studies as well as of turbulent mixing. The applied methods were based on thin-film gaseous models, on jelly models and liquid layer models. The research was done for plane and cylindrical geometries. As drivers, the shock tubes of different designs were used as well as gaseous explosive mixtures, compressed air and electric wire explosions. The experimental results were applied in calculational-theoretical technique calibrations. The authors did not aim at covering all VNIIEF research done in this field of science. To a great extent the choice of the material depended on the personal contribution of the author in these studies.« less
Larsson, Henrik
2016-04-01
Standard observational studies have reported a robust correlation between maternal smoking during pregnancy and risk of ADHD in offspring. In the accompanying article, Obel et al. used sibling-comparisons to explore the extent to which unmeasured familial confounding explains this association. This commentary highlights three important implications of the study. At a general level, Obel et al. illustrates how (1) family-based quasi-experimental designs and (2) national registers can be used to address confounding in risk factor studies of psychopathology. At a more specific level, the study suggests that maternal smoking during pregnancy is probably not a causal risk factor for ADHD. © 2016 Association for Child and Adolescent Mental Health.
Shen, Ye; Tan, Michelle Ting Ting; Chong, Clive; Xiao, Wende; Wang, Chi-Hwa
2017-10-01
Animal manure waste is considered as an environmental challenge especially in farming areas mainly because of gaseous emission and water pollution. Among all the pollutants emitted from manure waste, ammonia is of greatest concern as it could contribute to formation of aerosols in the air and could hardly be controlled by traditional disposal methods like landfill or composting. On the other hand, manure waste is also a renewable source for energy production. In this work, an environmental friendly animal waste disposal process with combined ammonia recovery and energy production was proposed and investigated both experimentally and economically. Lab-scale feasibility study results showed that 70% of ammonia in the manure waste could be converted to struvite as fertilizer, while solid manure waste was successfully gasified in a 10kW downdraft fixed-bed gasifier producing syngas with the higher heating value of 4.9MJ/(Nm 3 ). Based on experimental results, economic study for the system was carried out using a cost-benefit analysis to investigate the financial feasibility based on a Singapore case study. In addition, for comparison, schemes of gasification without ammonia removal and incineration were also studied for manure waste disposal. The results showed that the proposed gasification-based manure waste treatment process integrated with ammonia recovery was most financially viable. Copyright © 2017 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Hamid, H.
2018-01-01
The purpose of this study is to analyze an improvement of students’ mathematical critical thinking (CT) ability in Real Analysis course by using Rigorous Teaching and Learning (RTL) model with informal argument. In addition, this research also attempted to understand students’ CT on their initial mathematical ability (IMA). This study was conducted at a private university in academic year 2015/2016. The study employed the quasi-experimental method with pretest-posttest control group design. The participants of the study were 83 students in which 43 students were in the experimental group and 40 students were in the control group. The finding of the study showed that students in experimental group outperformed students in control group on mathematical CT ability based on their IMA (high, medium, low) in learning Real Analysis. In addition, based on medium IMA the improvement of mathematical CT ability of students who were exposed to RTL model with informal argument was greater than that of students who were exposed to CI (conventional instruction). There was also no effect of interaction between RTL model and CI model with both (high, medium, and low) IMA increased mathematical CT ability. Finally, based on (high, medium, and low) IMA there was a significant improvement in the achievement of all indicators of mathematical CT ability of students who were exposed to RTL model with informal argument than that of students who were exposed to CI.
Issues and recent advances in optimal experimental design for site investigation (Invited)
NASA Astrophysics Data System (ADS)
Nowak, W.
2013-12-01
This presentation provides an overview over issues and recent advances in model-based experimental design for site exploration. The addressed issues and advances are (1) how to provide an adequate envelope to prior uncertainty, (2) how to define the information needs in a task-oriented manner, (3) how to measure the expected impact of a data set that it not yet available but only planned to be collected, and (4) how to perform best the optimization of the data collection plan. Among other shortcomings of the state-of-the-art, it is identified that there is a lack of demonstrator studies where exploration schemes based on expert judgment are compared to exploration schemes obtained by optimal experimental design. Such studies will be necessary do address the often voiced concern that experimental design is an academic exercise with little improvement potential over the well- trained gut feeling of field experts. When addressing this concern, a specific focus has to be given to uncertainty in model structure, parameterizations and parameter values, and to related surprises that data often bring about in field studies, but never in synthetic-data based studies. The background of this concern is that, initially, conceptual uncertainty may be so large that surprises are the rule rather than the exception. In such situations, field experts have a large body of experience in handling the surprises, and expert judgment may be good enough compared to meticulous optimization based on a model that is about to be falsified by the incoming data. In order to meet surprises accordingly and adapt to them, there needs to be a sufficient representation of conceptual uncertainty within the models used. Also, it is useless to optimize an entire design under this initial range of uncertainty. Thus, the goal setting of the optimization should include the objective to reduce conceptual uncertainty. A possible way out is to upgrade experimental design theory towards real-time interaction with the ongoing site investigation, such that surprises in the data are immediately accounted for to restrict the conceptual uncertainty and update the optimization of the plan.
Park, Myung-Sook; Kweon, Young-Ran
2013-10-01
The purpose of this study was to examine the effects of a cultural competence improvement program for maternity nurses. A quasi-experimental study using a non-equivalent control group pre and posttest design was used. Participants were 67 maternity nurses caring for multicultural pregnant women in G city. The cultural competence improvement program was developed based on the 3-D Puzzle Model and was provided using case-based small group learning methods for the experimental group (n=31). The control group (n=36) did not receive any intervention. Data were collected using self-report structured questionnaires at two time points: prior to the intervention and after the intervention and were analyzed with descriptive statistics, χ²-test, and t-test. Compared to the control group, the experimental group reported significant positive changes for cultural knowledge (t=6.39, p<.001), cultural awareness (t=3.50, p<.001), and cultural acceptance (t=4.08, p<.001). However, change in cultural nursing behaviors (t=0.92, p=.067) was not significantly different between the two groups. Findings from this study indicate that a cultural competence improvement program with case-based small group learning is a useful intervention strategy to promote multicultural maternity care. Further, strategies to improve cultural nursing behavior should be developed to promote culturally congruent nursing care.
The Use of Video Feedback in Teaching Process-Approach EFL Writing
ERIC Educational Resources Information Center
Özkul, Sertaç; Ortaçtepe, Deniz
2017-01-01
This experimental study investigated the use of video feedback as an alternative to feedback with correction codes at an institution where the latter was commonly used for teaching process-approach English as a foreign language (EFL) writing. Over a 5-week period, the control and the experimental groups were provided with feedback based on…
Memory-Context Effects of Screen Color in Multiple-Choice and Fill-In Tests
ERIC Educational Resources Information Center
Prestera, Gustavo E.; Clariana, Roy; Peck, Andrew
2005-01-01
In this experimental study, 44 undergraduates completed five computer-based instructional lessons and either two multiplechoice tests or two fill-in-the-blank tests. Color-coded borders were displayed during the lesson, adjacent to the screen text and illustrations. In the experimental condition, corresponding border colors were shown at posttest.…
ERIC Educational Resources Information Center
Reijntjes, Albert; Dekovic, Maja; Vermande, Marjolijn; Telch, Michael J.
2007-01-01
The present study examined the linkage between pre-adolescent children's depressive symptoms and their preferences for receiving positive vs. negative feedback subsequent to being faced with an experimentally manipulated peer evaluation outcome in real time. Participants (n = 142) ages 10 to 13, played a computer contest based on the television…
Answer Me These Questions Three: Using Online Training to Improve Students' Oral Source Citations
ERIC Educational Resources Information Center
Buerkle, C. Wesley; Gearhart, Christopher C.
2017-01-01
This experimental study examines an online module designed to increase student competence in oral citation behavior using a mastery training strategy. Students in the experimental condition provided complete citations at a higher rate and provided more citation information for traditional and web-based sources compared with a control group without…
ERIC Educational Resources Information Center
Heene, Els; De Raedt, Rudi; Buysse, Ann; Van Oost, Paulette
2007-01-01
The present study was designed to test the influence of negative mood on the self-report of individual and relational correlates of depression and marital distress. The authors applied a combined experimental mood induction procedure, based on music, autobiographical recall, and environmental manipulation. Results showed that the mood manipulation…
Zhang, Cai-Xia; Long, Wei-Qing; Ye, Yan-Bin; Lu, Min-Shan; Zhang, Nai-Qi; Xu, Ming; Huang, Jing; Su, Yi-Xiang
2018-02-19
This cross-over experimental study aimed to examine the effects of filled chocolate consumption on blood glucose, insulin and ghrelin levels in 20 volunteers. After a one-week run-in period, study participants consumed two chocolate-based products, the tested biscuit or water for 21 days as a morning snack. After a two-week wash-out period, participants consumed another tested food for another 21 days. Each participant consumed all four test foods within an 18-week period. The participants' blood insulin increased slowly after two chocolate-based products intakes on the first day and satiety levels after eating chocolate-based products and the tested biscuit were the same. Chocolate consumption for three weeks had no adverse effects on blood glucose, insulin or ghrelin levels. In conclusion, compared to eating the tested biscuit, 21-day consumption of the tested chocolate-based products had no adverse effects on the blood glucose, insulin and ghrelin levels. This trial is registered with chictr.org.cn: ChiCTR-IOR-16009525.
Son, Hae Kyoung; Lim, Jiyoung
2014-10-01
To develop and evaluate the effects of a web-based education programme in early childhood for children with atopic dermatitis. The prevalence rate of atopic dermatitis is highest in early childhood. A holistic approach is urgently needed for young children with respect to disease severity, quality of life and management, particularly parental knowledge about atopic dermatitis and adherence to treatment. A quasi-experimental study design was used. A total of 40 mother-child dyads participated in the study from 1 July-30 November 2011 in Korea. All children were under 3 years of age. The programme was based on the Network-Based Instructional System Design model, which consists of five phases: analysis, design, development, implementation and evaluation. The experimental group participated in the programme for 2 weeks. Participants took part in a learning session during the first week and then conducted the practice session at home during the second week. Participant knowledge and compliance were evaluated through online quizzes and self-checklists. Statistical analyses (chi-square test and t-test) were performed using the Statistical Analysis System, Version 9.13. There was a significant improvement in disease severity, quality of life and mothers' self-efficacy in the experimental group; thus, the web-based education programme was effective. The web-based education programme as an advanced intervention may be useful in providing basic data for future atopic dermatitis-related studies. Moreover, the programme may serve as a nursing educational intervention tool for clinical nursing practices. © 2014 John Wiley & Sons Ltd.
An Exploratory Analysis of Projected Navy Officer Inventory Strength Using Data Farming
2016-09-01
model’s run-time. 3. Base Case In addition to the experimental design, this study includes a base case scenario to serve as a baseline for comparison...47 3. SWO Operating Strength Deviation-Base Case One objective of this study is to determine the risk in operating strength deviation presented by...ANSWERS TO RESEARCH QUESTIONS ................................... 71 B. RECOMMENDATIONS FOR FUTURE STUDIES ......................... 73 1. Continuous
NASA Astrophysics Data System (ADS)
Maghareh, Amin; Silva, Christian E.; Dyke, Shirley J.
2018-05-01
Hydraulic actuators play a key role in experimental structural dynamics. In a previous study, a physics-based model for a servo-hydraulic actuator coupled with a nonlinear physical system was developed. Later, this dynamical model was transformed into controllable canonical form for position tracking control purposes. For this study, a nonlinear device is designed and fabricated to exhibit various nonlinear force-displacement profiles depending on the initial condition and the type of materials used as replaceable coupons. Using this nonlinear system, the controllable canonical dynamical model is experimentally validated for a servo-hydraulic actuator coupled with a nonlinear physical system.
de la Garza-Rodea, Anabel Sofía; Padilla-Sánchez, Luis; de la Garza-Aguilar, Javier; Neri-Vela, Rolando
2007-01-01
The progress of medicine has largely been due to research, and for surgery, in particular, the experimental surgical laboratory has been considered fundamental to the surgeon's education. In this study, a general view of experimental surgery is given in animal models based on bioethical norms as well as to design, create and apply different surgical procedures before performing in humans. Experimental surgery also facilitates surgical teaching and promotes the surgeon's scientific reasoning. Methods. This is a retrospective and descriptive study. Data were collected from direct and indirect sources of available publications on the historical, bioethical and educational aspects of medicine, focusing on surgery. The important facts corresponding to the field of experimental surgery and applicable in Mexico were selected. Concepts of experimental surgical models and of the experimental surgery laboratory were described. Bioethical considerations are emphasized for care of experimental animals. Finally, this work focuses on the importance of surgical experimentation in current and future development of the surgical researcher. Conclusions. Experimentation with animal models in a surgical laboratory is essential for surgical teaching and promotes development of the scientific thought in the surgeon. It is necessary for surgical research and is fundamental for making progress in surgery, treatment and medicine as science.
Slofstra, Christien; Eisma, Maarten C; Holmes, Emily A; Bockting, Claudi L H; Nauta, Maaike H
2017-01-01
Ruminative (abstract verbal) processing during recall of aversive autobiographical memories may serve to dampen their short-term affective impact. Experimental studies indeed demonstrate that verbal processing of non-autobiographical material and positive autobiographical memories evokes weaker affective responses than imagery-based processing. In the current study, we hypothesized that abstract verbal or concrete verbal processing of an aversive autobiographical memory would result in weaker affective responses than imagery-based processing. The affective impact of abstract verbal versus concrete verbal versus imagery-based processing during recall of an aversive autobiographical memory was investigated in a non-clinical sample ( n = 99) using both an observational and an experimental design. Observationally, it was examined whether spontaneous use of processing modes (both state and trait measures) was associated with impact of aversive autobiographical memory recall on negative and positive affect. Experimentally, the causal relation between processing modes and affective impact was investigated by manipulating the processing mode during retrieval of the same aversive autobiographical memory. Main findings were that higher levels of trait (but not state) measures of both ruminative and imagery-based processing and depressive symptomatology were positively correlated with higher levels of negative affective impact in the observational part of the study. In the experimental part, no main effect of processing modes on affective impact of autobiographical memories was found. However, a significant moderating effect of depressive symptomatology was found. Only for individuals with low levels of depressive symptomatology, concrete verbal (but not abstract verbal) processing of the aversive autobiographical memory did result in weaker affective responses, compared to imagery-based processing. These results cast doubt on the hypothesis that ruminative processing of aversive autobiographical memories serves to avoid the negative emotions evoked by such memories. Furthermore, findings suggest that depressive symptomatology is associated with the spontaneous use and the affective impact of processing modes during recall of aversive autobiographical memories. Clinical studies are needed that examine the role of processing modes during aversive autobiographical memory recall in depression, including the potential effectiveness of targeting processing modes in therapy.
Ravikumar, Balaguru; Parri, Elina; Timonen, Sanna; Airola, Antti; Wennerberg, Krister
2017-01-01
Due to relatively high costs and labor required for experimental profiling of the full target space of chemical compounds, various machine learning models have been proposed as cost-effective means to advance this process in terms of predicting the most potent compound-target interactions for subsequent verification. However, most of the model predictions lack direct experimental validation in the laboratory, making their practical benefits for drug discovery or repurposing applications largely unknown. Here, we therefore introduce and carefully test a systematic computational-experimental framework for the prediction and pre-clinical verification of drug-target interactions using a well-established kernel-based regression algorithm as the prediction model. To evaluate its performance, we first predicted unmeasured binding affinities in a large-scale kinase inhibitor profiling study, and then experimentally tested 100 compound-kinase pairs. The relatively high correlation of 0.77 (p < 0.0001) between the predicted and measured bioactivities supports the potential of the model for filling the experimental gaps in existing compound-target interaction maps. Further, we subjected the model to a more challenging task of predicting target interactions for such a new candidate drug compound that lacks prior binding profile information. As a specific case study, we used tivozanib, an investigational VEGF receptor inhibitor with currently unknown off-target profile. Among 7 kinases with high predicted affinity, we experimentally validated 4 new off-targets of tivozanib, namely the Src-family kinases FRK and FYN A, the non-receptor tyrosine kinase ABL1, and the serine/threonine kinase SLK. Our sub-sequent experimental validation protocol effectively avoids any possible information leakage between the training and validation data, and therefore enables rigorous model validation for practical applications. These results demonstrate that the kernel-based modeling approach offers practical benefits for probing novel insights into the mode of action of investigational compounds, and for the identification of new target selectivities for drug repurposing applications. PMID:28787438
ERIC Educational Resources Information Center
Clarke, James B.; Coyle, James R.
2011-01-01
This article reports the results of a case study in which an experimental wiki knowledge base was designed, developed, and tested by the Brill Science Library at Miami University for an undergraduate engineering senior capstone project. The wiki knowledge base was created to determine if the science library could enhance the engineering literature…
ERIC Educational Resources Information Center
Demircioglu, Hülya; Ayas, Alipasa; Demircioglu, Gökhan; Özmen, Haluk
2015-01-01
In this study, the effect of the context-based approach on pre-service primary school teachers' understanding of matter and its states and their attitude towards chemistry was investigated. Using a simple experimental design, the study was conducted with 35 pre-service primary school teachers who were exposed to context-based material with…
ERIC Educational Resources Information Center
Chou, Pao-Nan; Chang, Chi-Cheng
2011-01-01
This study examines the effects of reflection category and reflection quality on learning outcomes during Web-based portfolio assessment process. Experimental subjects consist of forty-five eight-grade students in a "Computer Application" course. Through the Web-based portfolio assessment system, these students write reflection, and join…
Coherence Measurements for Excited to Excited State Transitions in Barium
NASA Technical Reports Server (NTRS)
Trajmar, S.; Kanik, I.; Karaganov, V.; Zetner, P. W.; Csanak, G.
2000-01-01
Experimental studies concerning elastic and inelastic electron scattering by coherently ensembles of Ba (...6s6p (sub 1)P(sub 1)) atoms with various degrees of alignment will be described. An in-plane, linearly-polarized laser beam was utilized to prepare these target ensembles and the electron scattering signal as a function of polarization angle was measured for several laser geometries at fixed impact energies and scattering angles. From these measurements, we derived cross sections and electron-impact coherence parameters associated with the electron scattering process which is time reverse of the actual experimentally studied process. This interpretation of the experiment is based on the theory of Macek and Herte. The experimental results were also interpreted in terms of cross sections and collision parameters associated with the actual experimental processes. Results obtained so far will be presented and plans for further studies will be discussed.
Ozdemir, F B; Selcuk, A B; Ozkorucuklu, S; Alpat, A B; Ozdemir, T; Ӧzek, N
2018-05-01
In this study, high-precision radiation detector (HIPRAD), a new-generation semiconductor microstrip detector, was used for detecting radon (Rn-222) activity. The aim of this study was to detect radon (Rn-222) activity experimentally by measuring the energy of particles in this detector. Count-ADC channel, eta-charge, and dose-response values were experimentally obtained using HIPRAD. The radon simulation in the radiation detector was theoretically performed using the Geant4 software package. The obtained radioactive decay, energy generation, energy values, and efficiency values of the simulation were plotted using the root program. The new-generation radiation detector proved to have 95% reliability according to the obtained dose-response graphs. The experimental and simulation results were found to be compatible with each other and with the radon decays and literature studies. Copyright © 2018 Elsevier Ltd. All rights reserved.
Attaining Reading Success through School-Wide and Content-Based Literacy
ERIC Educational Resources Information Center
Joseph Watts, Martha
2013-01-01
Reading performance among Grade 11 students has been low in the local school district under study. Schools within the boundaries of that setting have implemented research-based interventions to curb this problem of poor reading performance. A quasi-experimental, causal-comparative study was conducted to investigate the effect of Marzano's…
Assessing Student Openness to Inquiry-Based Learning in Precalculus
ERIC Educational Resources Information Center
Cooper, Thomas; Bailey, Brad; Briggs, Karen; Holliday, John
2017-01-01
The authors have completed a 2-year quasi-experimental study on the use of inquiry-based learning (IBL) in precalculus. This study included six traditional lecture-style courses and seven modified Moore method courses taught by three instructors. Both quantitative and qualitative analyses were used to investigate the attitudes and beliefs of the…
The Effect of Project Based Learning on Seventh Grade Students' Academic Achievement
ERIC Educational Resources Information Center
Kizkapan, Oktay; Bektas, Oktay
2017-01-01
The purpose of this study is to investigate whether there is a significant effect of project based learning approach on seventh grade students' academic achievement in the structure and properties of matter. In the study, according to the characteristics of quantitative research methods, pretest-posttest control group quasi-experimental design was…
ERIC Educational Resources Information Center
Saito, Kazuya; Akiyama, Yuka
2017-01-01
This study examined the impact of video-based conversational interaction on the longitudinal development (one academic semester) of second language production by college-level Japanese English-as-a-foreign-language learners. Students in the experimental group engaged in weekly dyadic conversation exchanges with native speakers in the United States…
Trait Based Assessment on Teaching Writing Skill for EFL Learners
ERIC Educational Resources Information Center
Asrobi, Maman; Prasetyaningrum, Ari
2017-01-01
This study was conducted in order to investigate the effectiveness of trait based assessment on teaching writing skill for EFL learners. Designed as pre-experimental study with one group pretest and posttest design, it examined 20 students of the second semester of English Department of "Hamzanwadi University" in the academic year…
Assessing Sensitivity of Early Head Start Study Findings to Manipulated Randomization Threats
ERIC Educational Resources Information Center
Green, Sheridan
2013-01-01
Increasing demands for design rigor and an emphasis on evidence-based practice on a national level indicated a need for further guidance related to successful implementation of randomized studies in education. Rigorous and meaningful experimental research and its conclusions help establish a valid theoretical and evidence base for educational…
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…
Effectiveness of a Solution-Based Counseling on Students' Self-Perception
ERIC Educational Resources Information Center
Joker, Habib; Ghaderi, Zahra
2015-01-01
The purpose of this study was to evaluate the effectiveness of solution-based counseling to increase students' self-conception. Method of research was semi-experimental with pretest and posttest design with a control group. The study sample consisted of all high school students in Dashtestan city, Bushkan district for which 30 subjects were…
ERIC Educational Resources Information Center
Alexander, Jennifer L.; Ayres, Kevin M.; Smith, Katie A.
2015-01-01
In this review, the authors include 23 studies where researchers experimentally evaluated training for teachers of students with Autism Spectrum Disorder (ASD). Authors summarized qualitative information on study and participant characteristics. Next, variables related to teacher practice and student learning targets were categorized based on…
Impact of Model-Based Teaching on Argumentation Skills
ERIC Educational Resources Information Center
Ogan-Bekiroglu, Feral; Belek, Deniz Eren
2014-01-01
The purpose of this study was to examine effects of model-based teaching on students' argumentation skills. Experimental design guided to the research. The participants of the study were pre-service physics teachers. The argumentative intervention lasted seven weeks. Data for this research were collected via video recordings and written arguments.…
ERIC Educational Resources Information Center
Abdelraheem, Ahmed Yousif; Ahmed, Abdelrahman Mohammed
2015-01-01
The study investigates the effect of Activity based Blended Learning strategy and Conventional Blended Learning strategy on students' achievement and motivation. Two groups namely, experimental and control group from Sultan Qaboos University were selected randomly for the study. To assess students' achievement in the different groups, pre- and…
An Experimental Study on the Iso-Content-Based Angle Similarity Measure.
ERIC Educational Resources Information Center
Zhang, Jin; Rasmussen, Edie M.
2002-01-01
Retrieval performance of the iso-content-based angle similarity measure within the angle, distance, conjunction, disjunction, and ellipse retrieval models is compared with retrieval performance of the distance similarity measure and the angle similarity measure. Results show the iso-content-based angle similarity measure achieves satisfactory…
The Translation of Basic Behavioral Research to School Psychology: A Citation Analysis
ERIC Educational Resources Information Center
Reed, Derek D.
2008-01-01
In recent years, school psychology has become increasingly grounded in data-based decision making and intervention design, based upon behavior analytic principles. This paradigm shift has occurred in part by recent federal legislation, as well as through advances in experimental research replicating laboratory based studies. Translating basic…
Effects of the Case-Based Instruction Method on the Experience of Learning
ERIC Educational Resources Information Center
Amiri Farahani, Leila; Heidari, Tooba
2014-01-01
This semi-experimental study was conducted with twenty-seven midwifery students who were randomly allocated to either case-based instruction or lecture-based instruction groups. The selected subjects -- foetal intrapartum assessment, foetal antepartum assessment, ABO and Rh blood group system mismatch -- were presented in four ninety-minute…
Palladino, Benedetta E; Nocentini, Annalaura; Menesini, Ersilia
2016-01-01
The NoTrap! (Noncadiamointrappola!) program is a school-based intervention, which utilizes a peer-led approach to prevent and combat both traditional bullying and cyberbullying. The aim of the present study was to evaluate the efficacy of the third Edition of the program in accordance with the recent criteria for evidence-based interventions. Towards this aim, two quasi-experimental trials involving adolescents (age M = 14.91, SD = .98) attending their first year at different high schools were conducted. In Trial 1 (control group, n = 171; experimental group, n = 451), latent growth curve models for data from pre-, middle- and post-tests showed that intervention significantly predicted change over time in all the target variables (victimization, bullying, cybervictimization, and cyberbullying). Specifically, target variables were stable for the control group but decreased significantly over time for the experimental group. Long-term effects at the follow up 6 months later were also found. In Trial 2 (control group, n = 227; experimental group, n = 234), the moderating effect of gender was examined and there was a reported decrease in bullying and cyberbullying over time (pre- and post-test) in the experimental group but not the control group, and this decrease was similar for boys and girls. © 2016 Wiley Periodicals, Inc.
NASA Astrophysics Data System (ADS)
Xu, Y. L.; Huang, Q.; Zhan, S.; Su, Z. Q.; Liu, H. J.
2014-06-01
How to use control devices to enhance system identification and damage detection in relation to a structure that requires both vibration control and structural health monitoring is an interesting yet practical topic. In this study, the possibility of using the added stiffness provided by control devices and frequency response functions (FRFs) to detect damage in a building complex was explored experimentally. Scale models of a 12-storey main building and a 3-storey podium structure were built to represent a building complex. Given that the connection between the main building and the podium structure is most susceptible to damage, damage to the building complex was experimentally simulated by changing the connection stiffness. To simulate the added stiffness provided by a semi-active friction damper, a steel circular ring was designed and used to add the related stiffness to the building complex. By varying the connection stiffness using an eccentric wheel excitation system and by adding or not adding the circular ring, eight cases were investigated and eight sets of FRFs were measured. The experimental results were used to detect damage (changes in connection stiffness) using a recently proposed FRF-based damage detection method. The experimental results showed that the FRF-based damage detection method could satisfactorily locate and quantify damage.
Experimental study on a magnetofluid sealing liquid for propeller shaft
NASA Astrophysics Data System (ADS)
Zhao, Chang-Fa; Sun, Rong-Hua; Zheng, Jin-Xing
2003-06-01
The selecting and preparing method of the basic material of magnetic fluid was introduced. By using a chemical method, the magnetic micropowder Fe3O4 was successfully yielded, and an oil-base as a working carrier and dispersing agent was determined. The preparation process of the magnetic fluid and prescription of the oil-base magnetic fluid were discussed. The simulation experimental rig of magnetic fluid sealing for propeller shaft was designed. The sealing ability experiment was conducted and results were analyzed. The pressure of sealing is up to 2 MPa.
Alumina additions may improve the damage tolerance of soft machined zirconia-based ceramics.
Oilo, Marit; Tvinnereim, Helene M; Gjerdet, Nils Roar
2011-01-01
The aim of this study was to evaluate the damage tolerance of different zirconia-based materials. Bars of one hard machined and one soft machined dental zirconia and an experimental 95% zirconia 5% alumina ceramic were subjected to 100,000 stress cycles (n = 10), indented to provoke cracks on the tensile stress side (n = 10), and left untreated as controls (n = 10). The experimental material demonstrated a higher relative damage tolerance, with a 40% reduction compared to 68% for the hard machined zirconia and 84% for the soft machined zirconia.
Polarization-insensitive techniques for optical signal processing
NASA Astrophysics Data System (ADS)
Salem, Reza
2006-12-01
This thesis investigates polarization-insensitive methods for optical signal processing. Two signal processing techniques are studied: clock recovery based on two-photon absorption in silicon and demultiplexing based on cross-phase modulation in highly nonlinear fiber. The clock recovery system is tested at an 80 Gb/s data rate for both back-to-back and transmission experiments. The demultiplexer is tested at a 160 Gb/s data rate in a back-to-back experiment. We experimentally demonstrate methods for eliminating polarization dependence in both systems. Our experimental results are confirmed by theoretical and numerical analysis.
Alsaggaf, Rotana; O'Hara, Lyndsay M; Stafford, Kristen A; Leekha, Surbhi; Harris, Anthony D
2018-02-01
OBJECTIVE A systematic review of quasi-experimental studies in the field of infectious diseases was published in 2005. The aim of this study was to assess improvements in the design and reporting of quasi-experiments 10 years after the initial review. We also aimed to report the statistical methods used to analyze quasi-experimental data. DESIGN Systematic review of articles published from January 1, 2013, to December 31, 2014, in 4 major infectious disease journals. METHODS Quasi-experimental studies focused on infection control and antibiotic resistance were identified and classified based on 4 criteria: (1) type of quasi-experimental design used, (2) justification of the use of the design, (3) use of correct nomenclature to describe the design, and (4) statistical methods used. RESULTS Of 2,600 articles, 173 (7%) featured a quasi-experimental design, compared to 73 of 2,320 articles (3%) in the previous review (P<.01). Moreover, 21 articles (12%) utilized a study design with a control group; 6 (3.5%) justified the use of a quasi-experimental design; and 68 (39%) identified their design using the correct nomenclature. In addition, 2-group statistical tests were used in 75 studies (43%); 58 studies (34%) used standard regression analysis; 18 (10%) used segmented regression analysis; 7 (4%) used standard time-series analysis; 5 (3%) used segmented time-series analysis; and 10 (6%) did not utilize statistical methods for comparisons. CONCLUSIONS While some progress occurred over the decade, it is crucial to continue improving the design and reporting of quasi-experimental studies in the fields of infection control and antibiotic resistance to better evaluate the effectiveness of important interventions. Infect Control Hosp Epidemiol 2018;39:170-176.
Vrahatis, Aristidis G; Rapti, Angeliki; Sioutas, Spyros; Tsakalidis, Athanasios
2017-01-01
In the era of Systems Biology and growing flow of omics experimental data from high throughput techniques, experimentalists are in need of more precise pathway-based tools to unravel the inherent complexity of diseases and biological processes. Subpathway-based approaches are the emerging generation of pathway-based analysis elucidating the biological mechanisms under the perspective of local topologies onto a complex pathway network. Towards this orientation, we developed PerSub, a graph-based algorithm which detects subpathways perturbed by a complex disease. The perturbations are imprinted through differentially expressed and co-expressed subpathways as recorded by RNA-seq experiments. Our novel algorithm is applied on data obtained from a real experimental study and the identified subpathways provide biological evidence for the brain aging.
ERIC Educational Resources Information Center
Tosun, Cemal; Senocak, Erdal
2013-01-01
The aim of this study was to reveal the effects of Problem-based Learning (PBL) on the metacognitive awareness and attitudes toward chemistry of teacher candidates with different academic backgrounds. The study was carried out on one group using both pre-and post-test experimental studies. The findings of the study were obtained through…
The effect of force feedback on student reasoning about gravity, mass, force and motion
NASA Astrophysics Data System (ADS)
Bussell, Linda
The purpose of this study was to examine whether force feedback within a computer simulation had an effect on reasoning by fifth grade students about gravity, mass, force, and motion, concepts which can be difficult for learners to grasp. Few studies have been done on cognitive learning and haptic feedback, particularly with young learners, but there is an extensive base of literature on children's conceptions of science and a number of studies focus specifically on children's conceptions of force and motion. This case study used a computer-based paddleball simulation with guided inquiry as the primary stimulus. Within the simulation, the learner could adjust the mass of the ball and the gravitational force. The experimental group used the simulation with visual and force feedback; the control group used the simulation with visual feedback but without force feedback. The proposition was that there would be differences in reasoning between the experimental and control groups, with force feedback being helpful with concepts that are more obvious when felt. Participants were 34 fifth-grade students from three schools. Students completed a modal (visual, auditory, and haptic) learning preference assessment and a pretest. The sessions, including participant experimentation and interviews, were audio recorded and observed. The interviews were followed by a written posttest. These data were analyzed to determine whether there were differences based on treatment, learning style, demographics, prior gaming experience, force feedback experience, or prior knowledge. Work with the simulation, regardless of group, was found to increase students' understanding of key concepts. The experimental group appeared to benefit from the supplementary help that force feedback provided. Those in the experimental group scored higher on the posttest than those in the control group. The greatest difference between mean group scores was on a question concerning the effects of increased gravitational force.
Knowledge Synthesis with Maps of Neural Connectivity
Tallis, Marcelo; Thompson, Richard; Russ, Thomas A.; Burns, Gully A. P. C.
2011-01-01
This paper describes software for neuroanatomical knowledge synthesis based on neural connectivity data. This software supports a mature methodology developed since the early 1990s. Over this time, the Swanson laboratory at USC has generated an account of the neural connectivity of the sub-structures of the hypothalamus, amygdala, septum, hippocampus, and bed nucleus of the stria terminalis. This is based on neuroanatomical data maps drawn into a standard brain atlas by experts. In earlier work, we presented an application for visualizing and comparing anatomical macro connections using the Swanson third edition atlas as a framework for accurate registration. Here we describe major improvements to the NeuARt application based on the incorporation of a knowledge representation of experimental design. We also present improvements in the interface and features of the data mapping components within a unified web-application. As a step toward developing an accurate sub-regional account of neural connectivity, we provide navigational access between the data maps and a semantic representation of area-to-area connections that they support. We do so based on an approach called “Knowledge Engineering from Experimental Design” (KEfED) model that is based on experimental variables. We have extended the underlying KEfED representation of tract-tracing experiments by incorporating the definition of a neuronanatomical data map as a measurement variable in the study design. This paper describes the software design of a web-application that allows anatomical data sets to be described within a standard experimental context and thus indexed by non-spatial experimental design features. PMID:22053155
Experimental study of a quantum random-number generator based on two independent lasers
NASA Astrophysics Data System (ADS)
Sun, Shi-Hai; Xu, Feihu
2017-12-01
A quantum random-number generator (QRNG) can produce true randomness by utilizing the inherent probabilistic nature of quantum mechanics. Recently, the spontaneous-emission quantum phase noise of the laser has been widely deployed for quantum random-number generation, due to its high rate, its low cost, and the feasibility of chip-scale integration. Here, we perform a comprehensive experimental study of a phase-noise-based QRNG with two independent lasers, each of which operates in either continuous-wave (CW) or pulsed mode. We implement the QRNG by operating the two lasers in three configurations, namely, CW + CW, CW + pulsed, and pulsed + pulsed, and demonstrate their trade-offs, strengths, and weaknesses.
Experimental and numerical analysis on noise reduction in a multi-blade centrifugal fan
NASA Astrophysics Data System (ADS)
Chen, X. J.; Y Cao, T.; Su, J.; Qin, G. L.
2013-12-01
In this work, analysis on noise source and reduction in a multi-blade centrifugal fan used for air-conditioners was carried out by experimental and numerical methods. Firstly, an experimental system using microphone mounted on volute surface for measuring surface pressure fluctuations of volute was designed and introduced, then surface pressure fluctuations of the whole volute for a multi-blade centrifugal fan were measured by this system, and the inlet noise for this fan was also obtained. And then, based on the experimental results, the aerodynamic noise source of the studied fan was analysed. The surface pressure fluctuations of the volute showed that there were largest surface pressure fluctuations near the volute tongue, and peaks appeared at the Blade Passing Frequency (BPF). The spectra of fan inlet noise showed that the peaks also appeared at BPF, and noise levels in a wide range of frequency were also larger. Secondly, the internal flow of the fan was simulated by commercial software under the same conditions with the experiment, and then the fluid flow and acoustic power field were obtained and discussed. The contours of acoustic power level showed that the larger noise was generated at the impeller area close to the outlet of scroll and at the volute tongue, which is same as that from experiment. Based on all of the results, we can find that the vortex noise is an important part of fan noise for the studied fan, and the rotation noise also cannot be neglected. Finally, several reduction methods that are thought to be effective based on experimental and numerical results were suggested.
NASA Astrophysics Data System (ADS)
Chavan, Durgeshkumar; Pise, Ashok T.
2015-09-01
In the present paper, experimental study is performed to investigate convective heat transfer and flow characteristics of nanofluids through a circular tube. The heat transfer coefficient and friction factor of the γ-Al2O3-water nanofluid flowing through a pipe of 10 mm inner ID and 1 m in length, with constant wall temperature under turbulent flow conditions are investigated. Experiments are conducted with 30 nm size γ-Al2O3 nanoparticle with a volume fraction between 0.1 and to 1.0 and Reynolds number between 8,000 and 14,000. Experimental results emphasize the heat transfer enhancement with the increase in a Reynolds number or nanoparticle volume fraction. The maximum enhancement of 36 % in the heat transfer coefficient for a Reynolds number of 8,550, by using nanofluid with 1.0 vol% was observed compared with base fluid. Experimental measurement also shows the considerable increase in the pressure drop with small addition of nanoparticles in base fluid. Experimental results of nanofluids were compared with existing convective heat transfer correlations in the turbulent regime. Comparison shows that Maiga's correlation has close agreement with experimental results in comparison with Dittus Boelter correlation.
Amidoxime Polymers for Uranium Adsorption: Influence of Comonomers and Temperature
Ladshaw, Austin P.; Wiechert, Alexander I.; Das, Sadananda; ...
2017-11-04
Recovering uranium from seawater has been the subject of many studies for decades, and has recently seen significant progress in materials development since the U.S. Department of Energy (DOE) has become involved. With DOE direction, the uranium uptake for amidoxime-based polymer adsorbents has more than tripled in capacity. In an effort to better understand how these new adsorbent materials behave under different environmental stimuli, several experimental and modeling based studies have been employed to investigate impacts of competing ions, salinity, pH, and other factors on uranium uptake. For this study, the effect of temperature and type of comonomer on uraniummore » adsorption by three different amidoxime adsorbents (AF1, 38H, AI8) was examined. Experimental measurements of uranium uptake were taken in 1–L batch reactors from 10 to 40 °C. A chemisorption model was developed and applied in order to estimate unknown system parameters through optimization. Experimental results demonstrated that the overall uranium chemisorption process for all three materials is endothermic, which was also mirrored in the model results. Model simulations show very good agreement with the data and were able to predict the temperature effect on uranium adsorption as experimental conditions changed. Here, this model may be used for predicting uranium uptake by other amidoxime materials.« less
Kumar, Sasi; Adiga, Kasturi Ramesh; George, Anice
2014-01-01
Old age is a period when people need physical, emotional, and psychological support. Depression is the most prevalent mental health problem among older adults and it contributes to increase in medical morbidity and mortality, reduces quality of life and elevates health care costs. Therefore early diagnosis and effective management are required to improve the quality of life of older adults suffering from depression. Intervention like Mindfulness based Stress Reduction is a powerful relaxation technique to provide quick way to get rid of depression and negative emotions by increasing mindfulness. The study was undertaken to assess the effectiveness of MBSR on depression among elderly residing in residential homes, Bangalore. In this study, quasi experimental pre-test post-test control group research design was used. There were two groups: experimental and control, each group had 30 samples selected from different residential homes by non-probability convenience sampling technique. Pre-test depression and mindfulness was assessed before the first day of intervention. Experimental group participants were provided intervention on MBSR. Assessment of post-test depression and mindfulness was done at the end of the intervention programme for both group participants. The study revealed significant reduction in depression (p < 0.001) and increase in mindfulness (p < 0.001) among elderly in the experimental group who were subjected to MBSR technique.
Amidoxime Polymers for Uranium Adsorption: Influence of Comonomers and Temperature
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ladshaw, Austin P.; Wiechert, Alexander I.; Das, Sadananda
Recovering uranium from seawater has been the subject of many studies for decades, and has recently seen significant progress in materials development since the U.S. Department of Energy (DOE) has become involved. With DOE direction, the uranium uptake for amidoxime-based polymer adsorbents has more than tripled in capacity. In an effort to better understand how these new adsorbent materials behave under different environmental stimuli, several experimental and modeling based studies have been employed to investigate impacts of competing ions, salinity, pH, and other factors on uranium uptake. For this study, the effect of temperature and type of comonomer on uraniummore » adsorption by three different amidoxime adsorbents (AF1, 38H, AI8) was examined. Experimental measurements of uranium uptake were taken in 1–L batch reactors from 10 to 40 °C. A chemisorption model was developed and applied in order to estimate unknown system parameters through optimization. Experimental results demonstrated that the overall uranium chemisorption process for all three materials is endothermic, which was also mirrored in the model results. Model simulations show very good agreement with the data and were able to predict the temperature effect on uranium adsorption as experimental conditions changed. Here, this model may be used for predicting uranium uptake by other amidoxime materials.« less
Innovative strategies for teaching nursing research in Taiwan.
Liou, Shwu-Ru; Cheng, Ching-Yu; Tsai, Hsiu-Min; Chang, Chia-Hao
2013-01-01
Evidence-based practice is imperative in clinical settings because it bridges the gap between research findings and clinical practice. Promoting nursing student interest and enthusiasm for research is therefore crucial when teaching nursing research. The aim of thus study was to develop innovative teaching strategies that increase nursing students' interests and engagement in research. This study employed a descriptive, pretest-posttest, quasiexperimental design with 103 participants in the experimental group and 106 in the control group. The Attitudes toward Research Questionnaire, Classroom Engagement Scale, Self-Directed Learning Instrument, Nursing Eight Core Competencies Scale, Value of Teams survey, and a research knowledge test were applied to evaluate the outcomes of the innovative teaching strategies. Scores for the research knowledge test were significantly higher in the experimental group than in the control group in posttest 1 and posttest 2. After the intervention, participants in the experimental group exhibited higher scores on attitudes toward research, eight core competencies in nursing,value of teams, classroom engagement, and self-directed learning than participants in the control group. Students in the experimental group perceived a lower degree of pressure and higher degrees of interest, enjoyment, and acceptance of the research course than students in the control group. This study confirmed that using innovative teaching strategies in nursing research courses enhances student interest and enthusiasm about evidence-based practice.
Amidoxime Polymers for Uranium Adsorption: Influence of Comonomers and Temperature
Wiechert, Alexander I.; Das, Sadananda; Yiacoumi, Sotira
2017-01-01
Recovering uranium from seawater has been the subject of many studies for decades, and has recently seen significant progress in materials development since the U.S. Department of Energy (DOE) has become involved. With DOE direction, the uranium uptake for amidoxime-based polymer adsorbents has more than tripled in capacity. In an effort to better understand how these new adsorbent materials behave under different environmental stimuli, several experimental and modeling based studies have been employed to investigate impacts of competing ions, salinity, pH, and other factors on uranium uptake. For this study, the effect of temperature and type of comonomer on uranium adsorption by three different amidoxime adsorbents (AF1, 38H, AI8) was examined. Experimental measurements of uranium uptake were taken in 1−L batch reactors from 10 to 40 °C. A chemisorption model was developed and applied in order to estimate unknown system parameters through optimization. Experimental results demonstrated that the overall uranium chemisorption process for all three materials is endothermic, which was also mirrored in the model results. Model simulations show very good agreement with the data and were able to predict the temperature effect on uranium adsorption as experimental conditions changed. This model may be used for predicting uranium uptake by other amidoxime materials. PMID:29113060
Small sarcocysts can be a feature of experimental infections with Sarcocystis neurona merozoites.
Marsh, Antoinette E; Chaney, Sarah B; Howe, Daniel K; Saville, William J; Reed, Stephen M
2017-10-15
Several reports indicate the presence of small tissue cysts associated with Sarcocystis neurona infections. Several failed attempts to develop tissue cysts in potential intermediate host using in vitro derived parasites originally isolated from horses with equine protozoal myeloencephalitis suggest that the experimental methods to achieve bradyzoites with those isolates was not possible. Those prior studies reported the lack of detectable sarcocysts based on histology and in vivo feeding trials. A recent report of successful production and detection of small sarcocysts triggered us to review archived tissues from earlier experimental infection studies. The retrospective review sought to determine if small sized sarcocysts were not detected due to their relatively smaller size and infrequency as compared to larger sized sarcocysts produced with other isolates in these experimental inoculation trials. Tissues from two prior in vivo inoculation studies, involving in vitro-produced parasites inoculated into laboratory-reared cats and raccoons, were re-examined by immunohistochemistry staining to more easily detect the tissue cysts. In the experimental cat study no small tissue cysts were seen, consistent with the original publication results. However, in the experimental raccoon study, one raccoon inoculated with an EPM-derived isolate, SN-UCD1, had small sarcocysts not reported in the original publication. This retrospective study suggests that much closer scrutiny of tissues, including the use of immunohistochemistry on tissue sections is required to detect the smaller S. neurona sarcocysts associated with the experimental inoculations of the isolates originally derived from horses with EPM. Published by Elsevier B.V.
ERIC Educational Resources Information Center
Uyanik, Gökhan
2016-01-01
The aim of the study is to determine effect of environmental education based on transformational learning theory on primary school teacher candidates' perceptions towards environmental problems and permanency of learning. Pretest-posttest quasi-experimental design have been used in this study. The study group consists of 66 teacher candidates who…
Effect of Constructivist Based Training on Learning and Teaching: An Experiment in Classroom
ERIC Educational Resources Information Center
Pandey, Laxmi; Ameta, Devendra
2017-01-01
The aim of the study was to study the effect of constructive based training approach on teachers' attitude and students' achievement. The study comprised 80 students of class VI from Nagar Palika Girls Middle School Balmiki Basti New Delhi and Nagar Palika Girls Sr. Sec. School, Havelock Square, New Delhi. A quasi experimental pre-test and…
ERIC Educational Resources Information Center
Arsal, Zeki
2017-01-01
In the study, the impact of inquiry-based learning on pre-service teachers' critical thinking dispositions was investigated. The sample of the study comprised of 56 pre-service teachers in the science education teacher education programme at the public university in the north of Turkey. In the study, quasi-experimental design with an experimental…
ERIC Educational Resources Information Center
Tsai, Chia-Wen; Shen, Pei-Di; Lin, Rong-An
2015-01-01
This study investigated, via quasi-experiments, the effects of student-centered project-based learning with initiation (SPBL with Initiation) on the development of students' computing skills. In this study, 96 elementary school students were selected from four class sections taking a course titled "Digital Storytelling" and were assigned…
[Disinfecting contact tonometers - a systematic review].
Neubauer, A S; Heeg, P; Kampik, A; Hirneiss, C
2009-05-01
The aim of this study is to provide the best available evidence on how to disinfect contact Goldman tonometers. A systematic review of all articles on disinfection of contact tonometers was conducted. Articles published up to July 2008 were identified in Medline, Embase and references from included articles. Two observers participated in the data retrieval and assessment of the studies identified. A total of 89 articles was retrieved, of which 58 could be included. Of those, 18 were clinical studies, 17 experimental microbiological studies, 8 expert assessments or guidelines and 15 reviews, surveys, descriptions of new methods. The clinical studies illustrate the importance of the problem, possible side effects of some disinfection methods but yield inconclusive results regarding efficacy. Experimental studies investigated a variety of bacterial and virological questions as well as material damage by disinfection. Both chlorine-based and hydrogen peroxide-based liquid disinfection were shown to be effective if applied for 5 min. Inconsistent results exist for alcohol wipes and UV disinfection - material damage has been described for both. The US guidelines and most expert recommendations are supported by evidence of the existing data. Chlorine-based and hydrogen peroxide-based liquid disinfections for 5 minutes are effective and relatively safe for disinfecting contact tonometers.
Momeni, Mohammad R; Cramer, Christopher J
2018-05-22
Recent experimental studies on Zr IV -based metal-organic frameworks (MOFs) have shown the extraordinary effectiveness of these porous materials for the detoxification of phosphorus-based chemical warfare agents (CWAs). However, pressing challenges remain with respect to characterizing these catalytic processes both at the molecular and crystalline levels. We here use theory to compare the reactivity of different zirconium-based MOFs for the catalytic hydrolysis of the CWA sarin, using both periodic and cluster modeling. We consider both hydrated and dehydrated secondary building units, as well as linker functionalized MOFs, to more fully understand and rationalize available experimental findings as well as to enable concrete predictions for achieving higher activities for the decomposition of CWAs.
Self-organized ferromagnetic nanowires in MgO-based magnetic tunnel junctions
NASA Astrophysics Data System (ADS)
Seike, Masayoshi; Fukushima, Tetsuya; Sato, Kazunori; Katayama-Yoshida, Hiroshi
2013-08-01
The focus of this study is to examine the distribution of defects and defect-induced properties in MgO-based magnetic tunnel junctions (MTJs). To this end, first-principles calculations were performed to estimate the electronic structures and total energies of MgO with various defects by using the Heyd-Scuseria-Ernzerhof (HSE06) hybrid functional. From connections drawn between the calculated results and previously reported experimental data, we propose that self-organized ferromagnetic nanowires of magnesium vacancies can be formed in MgO-based MTJs. This self-organization may provide the foundation for a comprehensive understanding of the conductivity, tunnel barriers and quantum oscillations of MgO-based MTJs. Further experimental verification is needed before firm conclusions can be drawn.
NASA Astrophysics Data System (ADS)
Afkhamipour, Morteza; Mofarahi, Masoud; Borhani, Tohid Nejad Ghaffar; Zanganeh, Masoud
2018-03-01
In this study, artificial neural network (ANN) and thermodynamic models were developed for prediction of the heat capacity ( C P ) of amine-based solvents. For ANN model, independent variables such as concentration, temperature, molecular weight and CO2 loading of amine were selected as the inputs of the model. The significance of the input variables of the ANN model on the C P values was investigated statistically by analyzing of correlation matrix. A thermodynamic model based on the Redlich-Kister equation was used to correlate the excess molar heat capacity ({C}_P^E) data as function of temperature. In addition, the effects of temperature and CO2 loading at different concentrations of conventional amines on the C P values were investigated. Both models were validated against experimental data and very good results were obtained between two mentioned models and experimental data of C P collected from various literatures. The AARD between ANN model results and experimental data of C P for 47 systems of amine-based solvents studied was 4.3%. For conventional amines, the AARD for ANN model and thermodynamic model in comparison with experimental data were 0.59% and 0.57%, respectively. The results showed that both ANN and Redlich-Kister models can be used as a practical tool for simulation and designing of CO2 removal processes by using amine solutions.
NASA Astrophysics Data System (ADS)
Nammi, Srinagalakshmi; Vasa, Nilesh J.; Gurusamy, Balaganesan; Mathur, Anil C.
2017-09-01
A plasma shielding phenomenon and its influence on micromachining is studied experimentally and theoretically for laser wavelengths of 355 nm, 532 nm and 1064 nm. A time resolved pump-probe technique is proposed and demonstrated by splitting a single nanosecond Nd3+:YAG laser into an ablation laser (pump laser) and a probe laser to understand the influence of plasma shielding on laser ablation of copper (Cu) clad on polyimide thin films. The proposed nanosecond pump-probe technique allows simultaneous measurement of the absorption characteristics of plasma produced during Cu film ablation by the pump laser. Experimental measurements of the probe intensity distinctly show that the absorption by the ablated plume increases with increase in the pump intensity, as a result of plasma shielding. Theoretical estimation of the intensity of the transmitted pump beam based on the thermo-temporal modeling is in qualitative agreement with the pump-probe based experimental measurements. The theoretical estimate of the depth attained for a single pulse with high pump intensity value on a Cu thin film is limited by the plasma shielding of the incident laser beam, similar to that observed experimentally. Further, the depth of micro-channels produced shows a similar trend for all three wavelengths, however, the channel depth achieved is lesser at the wavelength of 1064 nm.
NASA Astrophysics Data System (ADS)
Desai, Bhagyashree; Mokashi, Pavani; Anand, R. L.; Burli, S. B.; Khandal, S. V.
2016-09-01
The experimental study aims to underseek the effect of various additives on the green sand molding properties as a particular combination of additives could yield desired sand properties. The input parameters (factors) selected were water and powder (Fly ash, Coconut shell and Tamarind) in three levels. Experiments were planned using design of experiments (DOE). On the basis of plans, experiments were conducted to understand the behavior of sand mould properties such as compression strength, shear strength, permeability number with various additives. From the experimental results it could be concluded that the factors have significant effect on the sand properties as P-value found to be less than 0.05 for all the cases studied. The optimization based on quality loss function was also performed. The study revealed that the quality loss associated with the tamarind powder was lesser compared to other additives selected for the study. The optimization based on quality loss function and the parametric analysis using ANOVA suggested that the tamarind powder of 8 gm per Kg of molding sand and moisture content of 7% yield better properties to obtain sound castings.
Magnetic particle-mediated magnetoreception
Shaw, Jeremy; Boyd, Alastair; House, Michael; Woodward, Robert; Mathes, Falko; Cowin, Gary; Saunders, Martin; Baer, Boris
2015-01-01
Behavioural studies underpin the weight of experimental evidence for the existence of a magnetic sense in animals. In contrast, studies aimed at understanding the mechanistic basis of magnetoreception by determining the anatomical location, structure and function of sensory cells have been inconclusive. In this review, studies attempting to demonstrate the existence of a magnetoreceptor based on the principles of the magnetite hypothesis are examined. Specific attention is given to the range of techniques, and main animal model systems that have been used in the search for magnetite particulates. Anatomical location/cell rarity and composition are identified as two key obstacles that must be addressed in order to make progress in locating and characterizing a magnetite-based magnetoreceptor cell. Avenues for further study are suggested, including the need for novel experimental, correlative, multimodal and multidisciplinary approaches. The aim of this review is to inspire new efforts towards understanding the cellular basis of magnetoreception in animals, which will in turn inform a new era of behavioural research based on first principles. PMID:26333810
Wind-induced vibration of stay cables : brief
DOT National Transportation Integrated Search
2005-02-01
The objectives of this project were to: : Identify gaps in current knowledge base : Conduct analytical and experimental research in critical areas : Study performance of existing cable-stayed bridges : Study current mitigation methods...
Single- and two-phase flow in microfluidic porous media analogs based on Voronoi tessellation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wu, Mengjie; Xiao, Feng; Johnson-Paben, Rebecca
2012-01-01
The objective of this study was to create a microfluidic model of complex porous media for studying single and multiphase flows. Most experimental porous media models consist of periodic geometries that lend themselves to comparison with well-developed theoretical predictions. However, most real porous media such as geological formations and biological tissues contain a degree of randomness and complexity that is not adequately represented in periodic geometries. To design an experimental tool to study these complex geometries, we created microfluidic models of random homogeneous and heterogeneous networks based on Voronoi tessellations. These networks consisted of approximately 600 grains separated by amore » highly connected network of channels with an overall porosity of 0.11 0.20. We found that introducing heterogeneities in the form of large cavities within the network changed the permeability in a way that cannot be predicted by the classical porosity-permeability relationship known as the Kozeny equation. The values of permeability found in experiments were in excellent agreement with those calculated from three-dimensional lattice Boltzmann simulations. In two-phase flow experiments of oil displacement with water we found that the surface energy of channel walls determined the pattern of water invasion, while the network topology determined the residual oil saturation. These results suggest that complex network topologies lead to fluid flow behavior that is difficult to predict based solely on porosity. The microfluidic models developed in this study using a novel geometry generation algorithm based on Voronoi tessellation are a new experimental tool for studying fluid and solute transport problems within complex porous media.« less
Mariano-Goulart, D; Fourcade, M; Bernon, J L; Rossi, M; Zanca, M
2003-01-01
Thanks to an experimental study based on simulated and physical phantoms, the propagation of the stochastic noise in slices reconstructed using the conjugate gradient algorithm has been analysed versus iterations. After a first increase corresponding to the reconstruction of the signal, the noise stabilises before increasing linearly with iterations. The level of the plateau as well as the slope of the subsequent linear increase depends on the noise in the projection data.
Interface Pattern Selection Criterion for Cellular Structures in Directional Solidification
NASA Technical Reports Server (NTRS)
Trivedi, R.; Tewari, S. N.; Kurtze, D.
1999-01-01
The aim of this investigation is to establish key scientific concepts that govern the selection of cellular and dendritic patterns during the directional solidification of alloys. We shall first address scientific concepts that are crucial in the selection of interface patterns. Next, the results of ground-based experimental studies in the Al-4.0 wt % Cu system will be described. Both experimental studies and theoretical calculations will be presented to establish the need for microgravity experiments.
NASA Astrophysics Data System (ADS)
Bumbacher, Engin; Salehi, Shima; Wieman, Carl; Blikstein, Paulo
2017-12-01
Manipulative environments play a fundamental role in inquiry-based science learning, yet how they impact learning is not fully understood. In a series of two studies, we develop the argument that manipulative environments (MEs) influence the kind of inquiry behaviors students engage in, and that this influence realizes through the affordances of MEs, independent of whether they are physical or virtual. In particular, we examine how MEs shape college students' experimentation strategies and conceptual understanding. In study 1, students engaged in two consecutive inquiry tasks, first on mass and spring systems and then on electric circuits. They either used virtual or physical MEs. We found that the use of experimentation strategies was strongly related to conceptual understanding across tasks, but that students engaged differently in those strategies depending on what ME they used. More students engaged in productive strategies using the virtual ME for electric circuits, and vice versa using the physical ME for mass and spring systems. In study 2, we isolated the affordance of measurement uncertainty by comparing two versions of the same virtual ME for electric circuits—one with and one without noise—and found that the conditions differed in terms of productive experimentation strategies. These findings indicate that measures of inquiry processes may resolve apparent ambiguities and inconsistencies between studies on MEs that are based on learning outcomes alone.
Ghanbari, F; Rowland-Yeo, K; Bloomer, J C; Clarke, S E; Lennard, M S; Tucker, G T; Rostami-Hodjegan, A
2006-04-01
The published literature on mechanism based inhibition (MBI) of CYPs was evaluated with respect to experimental design, methodology and data analysis. Significant variation was apparent in the dilution factor, ratio of preincubation to incubation times and probe substrate concentrations used, and there were some anomalies in the estimation of associated kinetic parameters (k(inact), K(I), r). The impact of the application of inaccurate values of k(inact) and K(I) when extrapolating to the extent of inhibition in vivo is likely to be greatest for those compounds of intermediate inhibitory potency, but this also depends on the fraction of the net clearance of substrate subject to MBI and the pre-systemic and systemic exposure to the inhibitor. For potent inhibitors, the experimental procedure is unlikely to have a material influence on the maximum inhibition. Nevertheless, the bias in the values of the kinetic parameters may influence the time for recovery of enzyme activity following re-synthesis of the enzyme. Careful attention to the design of in vitro experiments to obtain accurate kinetic parameters is necessary for a reliable prediction of different aspects of the in vivo consequences of MBI. The review calls for experimental studies to quantify the impact of study design in studies of MBI, with a view to better harmonisation of protocols.
Sampling flies or sampling flaws? Experimental design and inference strength in forensic entomology.
Michaud, J-P; Schoenly, Kenneth G; Moreau, G
2012-01-01
Forensic entomology is an inferential science because postmortem interval estimates are based on the extrapolation of results obtained in field or laboratory settings. Although enormous gains in scientific understanding and methodological practice have been made in forensic entomology over the last few decades, a majority of the field studies we reviewed do not meet the standards for inference, which are 1) adequate replication, 2) independence of experimental units, and 3) experimental conditions that capture a representative range of natural variability. Using a mock case-study approach, we identify design flaws in field and lab experiments and suggest methodological solutions for increasing inference strength that can inform future casework. Suggestions for improving data reporting in future field studies are also proposed.
Development and Evaluation of the Diagnostic Power for a Computer-Based Two-Tier Assessment
ERIC Educational Resources Information Center
Lin, Jing-Wen
2016-01-01
This study adopted a quasi-experimental design with follow-up interview to develop a computer-based two-tier assessment (CBA) regarding the science topic of electric circuits and to evaluate the diagnostic power of the assessment. Three assessment formats (i.e., paper-and-pencil, static computer-based, and dynamic computer-based tests) using…
The Effect of Modeling Based Science Education on Critical Thinking
ERIC Educational Resources Information Center
Bati, Kaan; Kaptan, Fitnat
2015-01-01
In this study to what degree the modeling based science education can influence the development of the critical thinking skills of the students was investigated. The research was based on pre-test-post-test quasi-experimental design with control group. The Modeling Based Science Education Program which was prepared with the purpose of exploring…
Hu, Chao; Wang, Qianxin; Wang, Zhongyuan; Hernández Moraleda, Alberto
2018-01-01
Currently, five new-generation BeiDou (BDS-3) experimental satellites are working in orbit and broadcast B1I, B3I, and other new signals. Precise satellite orbit determination of the BDS-3 is essential for the future global services of the BeiDou system. However, BDS-3 experimental satellites are mainly tracked by the international GNSS Monitoring and Assessment Service (iGMAS) network. Under the current constraints of the limited data sources and poor data quality of iGMAS, this study proposes an improved cycle-slip detection and repair algorithm, which is based on a polynomial prediction of ionospheric delays. The improved algorithm takes the correlation of ionospheric delays into consideration to accurately estimate and repair cycle slips in the iGMAS data. Moreover, two methods of BDS-3 experimental satellite orbit determination, namely, normal equation stacking (NES) and step-by-step (SS), are designed to strengthen orbit estimations and to make full use of the BeiDou observations in different tracking networks. In addition, a method to improve computational efficiency based on a matrix eigenvalue decomposition algorithm is derived in the NES. Then, one-year of BDS-3 experimental satellite precise orbit determinations were conducted based on iGMAS and Multi-GNSS Experiment (MGEX) networks. Furthermore, the orbit accuracies were analyzed from the discrepancy of overlapping arcs and satellite laser range (SLR) residuals. The results showed that the average three-dimensional root-mean-square error (3D RMS) of one-day overlapping arcs for BDS-3 experimental satellites (C31, C32, C33, and C34) acquired by NES and SS are 31.0, 36.0, 40.3, and 50.1 cm, and 34.6, 39.4, 43.4, and 55.5 cm, respectively; the RMS of SLR residuals are 55.1, 49.6, 61.5, and 70.9 cm and 60.5, 53.6, 65.8, and 73.9 cm, respectively. Finally, one month of observations were used in four schemes of BDS-3 experimental satellite orbit determination to further investigate the reliability and advantages of the improved methods. It was suggested that the scheme with improved cycle-slip detection and repair algorithm based on NES was optimal, which improved the accuracy of BDS-3 experimental satellite orbits by 34.07%, 41.05%, 72.29%, and 74.33%, respectively, compared with the widely-used strategy. Therefore, improved methods for the BDS-3 experimental satellites proposed in this study are very beneficial for the determination of new-generation BeiDou satellite precise orbits. PMID:29724062
NASA Astrophysics Data System (ADS)
Abbiati, Giuseppe; La Salandra, Vincenzo; Bursi, Oreste S.; Caracoglia, Luca
2018-02-01
Successful online hybrid (numerical/physical) dynamic substructuring simulations have shown their potential in enabling realistic dynamic analysis of almost any type of non-linear structural system (e.g., an as-built/isolated viaduct, a petrochemical piping system subjected to non-stationary seismic loading, etc.). Moreover, owing to faster and more accurate testing equipment, a number of different offline experimental substructuring methods, operating both in time (e.g. the impulse-based substructuring) and frequency domains (i.e. the Lagrange multiplier frequency-based substructuring), have been employed in mechanical engineering to examine dynamic substructure coupling. Numerous studies have dealt with the above-mentioned methods and with consequent uncertainty propagation issues, either associated with experimental errors or modelling assumptions. Nonetheless, a limited number of publications have systematically cross-examined the performance of the various Experimental Dynamic Substructuring (EDS) methods and the possibility of their exploitation in a complementary way to expedite a hybrid experiment/numerical simulation. From this perspective, this paper performs a comparative uncertainty propagation analysis of three EDS algorithms for coupling physical and numerical subdomains with a dual assembly approach based on localized Lagrange multipliers. The main results and comparisons are based on a series of Monte Carlo simulations carried out on a five-DoF linear/non-linear chain-like systems that include typical aleatoric uncertainties emerging from measurement errors and excitation loads. In addition, we propose a new Composite-EDS (C-EDS) method to fuse both online and offline algorithms into a unique simulator. Capitalizing from the results of a more complex case study composed of a coupled isolated tank-piping system, we provide a feasible way to employ the C-EDS method when nonlinearities and multi-point constraints are present in the emulated system.
Caliskan Yilmaz, Medine; Ozsoy, Suheyla A
2010-02-01
The purpose of this study was to investigate the effectiveness of a discharge-planning program on helping caregivers meet the physical care needs of children with cancer. This research is a quasi-experimental type of study in a pediatric oncology clinic at a university hospital in Izmir/Turkey. The control group had 25 and the experimental group had 24 patients with their caregivers. For the experimental group, discharge planning, discharge teaching, home visits, and telephone consultation were provided and has been planned to investigate the effectiveness of a discharge-planning program on helping caregivers meet the physical care needs of children with cancer between 0-18 years of age. In the third assessment, the number of patients that needed physical care needs in the experimental and control groups was decreased, and children in the experimental group had a lower number of physical care needs. A decreased number of unplanned admissions to the hospital at the first and third follow-up times, a decrease in unplanned admissions, and higher satisfaction rate were seen in the experimental group caregivers. A discharge-planning program and a hospital-based home care model had a very significant effect on the care needs of children with cancer and their caregivers. Our findings indicate that a discharge-planning program and a hospital-based home care model had a very significant effect on the care needs of children with cancer and their caregivers.
NASA Astrophysics Data System (ADS)
Boruah, Manash J.; Ahmed, Gazi A.
2018-01-01
Laser based experimental light scattering studies of irregularly shaped silica microparticles have been performed at three incident wavelengths 543.5 nm, 594.5 nm and 632.8 nm supported by laboratory based computations and 3D realistic simulations, using an indigenously fabricated light scattering setup. A comparative analysis of the computational and experimentally acquired results is done and a good agreement is found in the forward scattering lobes in all cases for each of the measured scattering parameters. This study also provides an efficient way of detecting and measuring particle size distribution for irregular micro- and nanoparticles and is highly applicable in remote sensing, atmospheric, astrophysical, and medical applications and also for finding potential health hazards in the form of inhalable and respirable small particulate matter.
An Experimental Comparison Between Flexible and Rigid Airfoils at Low Reynolds Numbers
NASA Astrophysics Data System (ADS)
Uzodinma, Jaylon; Macphee, David
2017-11-01
This study uses experimental and computational research methods to compare the aerodynamic performance of rigid and flexible airfoils at a low Reynolds number throughout varying angles of attack. This research can be used to improve the design of small wind turbines, micro-aerial vehicles, and any other devices that operate at low Reynolds numbers. Experimental testing was conducted in the University of Alabama's low-speed wind tunnel, and computational testing was conducted using the open-source CFD code OpenFOAM. For experimental testing, polyurethane-based (rigid) airfoils and silicone-based (flexible) airfoils were constructed using acrylic molds for NACA 0012 and NACA 2412 airfoil profiles. Computer models of the previously-specified airfoils were also created for a computational analysis. Both experimental and computational data were analyzed to examine the critical angles of attack, the lift and drag coefficients, and the occurrence of laminar boundary separation for each airfoil. Moreover, the computational simulations were used to examine the resulting flow fields, in order to provide possible explanations for the aerodynamic performances of each airfoil type. EEC 1659710.
Podhajski, Blanche; Mather, Nancy; Nathan, Jane; Sammons, Janice
2009-01-01
This article reviews the literature and presents data from a study that examined the effects of professional development in scientifically based reading instruction on teacher knowledge and student reading outcomes. The experimental group consisted of four first- and second-grade teachers and their students (n = 33). Three control teachers and their students (n = 14), from a community of significantly higher socioeconomic demographics, were also followed. Experimental teachers participated in a 35-hour course on instruction of phonemic awareness, phonics, and fluency and were coached by professional mentors for a year. Although teacher knowledge in the experimental group was initially lower than that of the controls, their scores surpassed the controls on the posttest. First-grade experimental students' growth exceeded the controls in letter name fluency, phonemic segmentation, nonsense word fluency, and oral reading. Second-grade experimental students exceeded controls in phonemic segmentation. Although the teacher sample was small, findings suggest that teachers can improve their knowledge concerning explicit reading instruction and that this new knowledge may contribute to student growth in reading.
Kim, Shin-Jeong; Shin, Hyewon; Lee, Jungeun; Kang, SoRa; Bartlett, Robin
2017-01-01
This study had two aims: (a) to develop a smartphone-based application and (b) to evaluate the effectiveness of the application by measuring nursing students' knowledge, skills, and confidence in simulated performance when providing that care. We conducted a randomized trial using a pre- and post-test design at a university in Korea. Seventy-three junior nursing students participated. A smartphone-based app using a video was developed for the experimental group and one time lecture-based education was designed for the control group. We provided the app and information about its use to the experimental group, and we encouraged its use. We provided classroom instruction to the control group. Then, learning outcomes were evaluated. The smartphone-based education group showed significantly higher scores on skills (t=4.774, p<0.001) and confidence in performance (t=2.888, p=0.005) than the control group. The scores on knowledge (t=0.886, p=0.379) and satisfaction with the learning method (t=0.168, p=0.867) for the experimental group were higher than for the control group, but the differences were not statistically significant. This study suggests that smartphone-based education may be an effective method to use in nursing education related to teaching infant airway obstruction. Copyright © 2016 Elsevier Ltd. All rights reserved.
Wang, Hee Jung; Kim, Il Ok
2015-06-01
This study was conducted to develop a mobile web-based pregnancy health care educational program for mothers who were at an advanced maternal age (AMA) and to verify the effects of the program on pregnancy health care. This program was developed using a web-based teaching-learning system design model and composed of 10 subject areas. This research was a quasi-experimental study using a non-equivalent control group pretest-posttest time serial design and data were collected from April 2 to May 3, 2014. To verify the effects of the program, it was used for 2 weeks with 30 AMA mothers (experimental group). For the control group, a classroom education booklet for pregnant women used with 31 AMA mothers. The experimental group having participated in program had statistically significantly higher scores for knowledge (t=3.76, p<.001), self-efficacy (t=8.54, p<.001), and practice behavior (t=4.88, p<.001) of pregnancy health care, compared to the control group. The results of the program indicate that a Mobile web-based pregnancy health care educational program is effective in meeting the needs of AMA mothers and can be used as the prenatal educational program for AMA mothers and is appropriate as an educational media for theses mothers.
Freire, Mara G; Neves, Catarina M S S; Shimizu, Karina; Bernardes, Carlos E S; Marrucho, Isabel M; Coutinho, João A P; Canongia Lopes, José N; Rebelo, Luís Paulo N
2010-12-09
Despite many previous important contributions to the characterization of the liquid-liquid phase behavior of ionic liquids (ILs) plus water systems, a gap still exists as far as the effect of isomers (of ILs) is concerned. Therefore, in this work, a comprehensive study of the liquid-liquid equilibria between water and isomeric pyridinium-based ionic liquids has been performed. Atmospheric pressure mutual solubilities between water and pyridinium-based ionic liquids combined with the common anion bis[(trifluoromethyl)sulfonyl]imide were experimentally determined between (288.15 and 318.15) K. The main goal of this work is to study the isomeric effects on the pyridinium-based cation, namely, the structural and positional isomerism, as well as the alkyl side chain length. To the best of our knowledge, the influence of both structural and positional isomerism on the liquid-liquid behavior in ionic-liquid-water-containing systems is an unexplored field and is here assessed for the first time. Moreover, from the experimental solubility data, several infinite dilution molar thermodynamic functions of solution, namely, the Gibbs energy, the enthalpy, and the entropy, were estimated and discussed. In addition, aiming at gathering a broader picture of the underlying thermodynamic solvation phenomenon, molecular dynamics simulations were also carried out for the same experimental systems.
Tsai, Cheng-Yu; Jiang, Jhih-Shan
2018-01-01
A micro-projection enabled short-range communication (SRC) approach using red-, green- and blue-based light-emitting diodes (RGB-LEDs) has experimentally demonstrated recently that micro-projection and high-speed data transmission can be performed simultaneously. In this research, a reconfigurable design of a polarization modulated image system based on the use of a Liquid Crystal on Silicon based Spatial Light Modulator (LCoS-based SLM) serving as a portable optical terminal capable of micro-projection and bidirectional multi-wavelength communications is proposed and experimentally demonstrated. For the proof of concept, the system performance was evaluated through a bidirectional communication link at a transmission distance over 0.65 m. In order to make the proposed communication system architecture compatible with the data modulation format of future possible wireless communication system, baseband modulation scheme, i.e., Non-Return-to-Zero On-Off-Keying (NRZ_OOK), M-ary Phase Shift Keying (M-PSK) and M-ary Quadrature Amplitude Modulation (M-QAM) were used to investigate the system transmission performance. The experimental results shown that an acceptable BER (satisfying the limitation of Forward Error Correction, FEC standard) and crosstalk can all be achieved in the bidirectional multi-wavelength communication scenario. PMID:29587457
The Use of Interrupted Case Studies to Enhance Critical Thinking Skills in Biology
White, Tracy K.; Whitaker, Paul; Gonya, Terri; Hein, Richard; Kroening, Dubear; Lee, Kevin; Lee, Laura; Lukowiak, Andrea; Hayes, Elizabeth
2009-01-01
There has been a dramatic increase in the availability of case studies for use in the biology classroom, and perceptions of the effectiveness of case-study-based learning are overwhelmingly positive. Here we report the results of a study in which we evaluated the ability of interrupted case studies to improve critical thinking in the context of experimental design and the conventions of data interpretation. Students were assessed using further case studies designed to evaluate their ability to recognize and articulate problematic approaches to these elements of experimentation. Our work reveals that case studies have broad utility in the classroom. In addition to demonstrating a small but statistically significant increase in the number of students capable of critically evaluating selected aspects of experimental design, we also observed increased student engagement and documented widespread misconceptions regarding the conventions of data acquisition and analysis. PMID:23653687
Jaciw, Andrew P
2016-06-01
Various studies have examined bias in impact estimates from comparison group studies (CGSs) of job training programs, and in education, where results are benchmarked against experimental results. Such within-study comparison (WSC) approaches investigate levels of bias in CGS-based impact estimates, as well as the success of various design and analytic strategies for reducing bias. This article reviews past literature and summarizes conditions under which CGSs replicate experimental benchmark results. It extends the framework to, and develops the methodology for, situations where results from CGSs are generalized to untreated inference populations. Past research is summarized; methods are developed to examine bias in program impact estimates based on cross-site comparisons in a multisite trial that are evaluated against site-specific experimental benchmarks. Students in Grades K-3 in 79 schools in Tennessee; students in Grades 4-8 in 82 schools in Alabama. Grades K-3 Stanford Achievement Test (SAT) in reading and math scores; Grades 4-8 SAT10 reading scores. Past studies show that bias in CGS-based estimates can be limited through strong design, with local matching, and appropriate analysis involving pretest covariates and variables that represent selection processes. Extension of the methodology to investigate accuracy of generalized estimates from CGSs shows bias from confounders and effect moderators. CGS results, when extrapolated to untreated inference populations, may be biased due to variation in outcomes and impact. Accounting for effects of confounders or moderators may reduce bias. © The Author(s) 2016.
NASA Astrophysics Data System (ADS)
Usmeldi
2018-05-01
The preliminary study shows that many students are difficult to master the concept of physics. There are still many students who have not mastery learning physics. Teachers and students still use textbooks. Students rarely do experiments in the laboratory. One model of learning that can improve students’ competence is a research-based learning with Predict- Observe-Explain (POE) strategies. To implement this learning, research-based physics learning modules with POE strategy are used. The research aims to find out the effectiveness of implementation of research-based physics learning modules with POE strategy to improving the students’ competence. The research used a quasi-experimental with pretest-posttest group control design. Data were collected using observation sheets, achievement test, skill assessment sheets, questionnaire of attitude and student responses to learning implementation. The results of research showed that research-based physics learning modules with POE strategy was effective to improve the students’ competence, in the case of (1) mastery learning of physics has been achieved by majority of students, (2) improving the students competency of experimental class including high category, (3) there is a significant difference between the average score of students’ competence of experimental class and the control class, (4) the average score of the students competency of experimental class is higher than the control class, (5) the average score of the students’ responses to the learning implementation is very good category, this means that most students can implement research-based learning with POE strategies.
Huang, Ya-Hsuan; Hsieh, Suh-Ing; Hsu, Li-Ling
2014-04-01
Limited disease knowledge is frequently the cause of disease-related anxiety in myocardial infarction patients. The ability to communicate effectively serves multiple purposes in the professional nursing practice. By communicating effectively with myocardial infarction patients, nurses may help reduce their anxiety by keeping them well informed about their disease and teaching them self-care strategies. This research evaluates the communication skills of nurses following scenario-based simulation education in the context of communication with myocardial infarction patients. This study used an experimental design and an educational intervention. The target population comprised nurses of medicine (clinical qualified level N to N2 for nursing) working at a municipal hospital in Taipei City, Taiwan. A total 122 participants were enrolled. Stratified block randomization divided participants into an experimental group and a control group. The experimental group received clinical scenario-based simulation education for communication. The control group received traditional class-based education for communication. Both groups received a pre-test and a Communication Skills Checklist post-test assessment. Results were analyzed using SPSS 17.0 for Windows software. A t-test showed significant increases in communication skills (p < .001) in the experimental group and ANCOVA results identified significant between-group differences (p < .001) in communication skills following the education intervention. The results indicate that clinical scenario-based simulation education for communication is significantly more effective than traditional class-based education in enhancing the ability of nurses to communicate effectively with myocardial infarction patients.
NASA Technical Reports Server (NTRS)
Partridge, William P.; Laurendeau, Normand M.
1997-01-01
We have experimentally assessed the quantitative nature of planar laser-induced fluorescence (PLIF) measurements of NO concentration in a unique atmospheric pressure, laminar, axial inverse diffusion flame (IDF). The PLIF measurements were assessed relative to a two-dimensional array of separate laser saturated fluorescence (LSF) measurements. We demonstrated and evaluated several experimentally-based procedures for enhancing the quantitative nature of PLIF concentration images. Because these experimentally-based PLIF correction schemes require only the ability to make PLIF and LSF measurements, they produce a more broadly applicable PLIF diagnostic compared to numerically-based correction schemes. We experimentally assessed the influence of interferences on both narrow-band and broad-band fluorescence measurements at atmospheric and high pressures. Optimum excitation and detection schemes were determined for the LSF and PLIF measurements. Single-input and multiple-input, experimentally-based PLIF enhancement procedures were developed for application in test environments with both negligible and significant quench-dependent error gradients. Each experimentally-based procedure provides an enhancement of approximately 50% in the quantitative nature of the PLIF measurements, and results in concentration images nominally as quantitative as LSF point measurements. These correction procedures can be applied to other species, including radicals, for which no experimental data are available from which to implement numerically-based PLIF enhancement procedures.
ERIC Educational Resources Information Center
Powell, Tara; Thompson, Sanna J.
2016-01-01
Objective: This article presents the Journey of Hope (JoH), a school-based intervention for children who have experienced a collective trauma such as a natural disaster. Through the use of group work, the JoH focuses on building coping skills and enhancing protective factors to help children recover. Method: This quasi-experimental research…
ERIC Educational Resources Information Center
Turnšek, Nada
2013-01-01
The present study is based on a quasi-experimental research design and presents the results of an evaluation of Antidiscrimination and Diversity Training that took place at the Faculty of Education in Ljubljana, rooted in the anti-bias approach to educating diversity and equality issues (Murray & Urban, 2012). The experimental group included…
ERIC Educational Resources Information Center
Li, Xiaoming; Zhang, Liying; Mao, Rong; Zhao, Qun; Stanton, Bonita
2011-01-01
This study was designed to evaluate potential preventive effects of a cultural adaption of the Focus on Kids (FOK) program among Chinese adolescents through a quasi-experimental intervention trial in Nanjing, China. High school students were assigned to either experimental groups (n = 140) or control groups (n = 164) by schools (with three schools…
Effects of Training Method and Gender on Learning 2D/3D Geometry
ERIC Educational Resources Information Center
Khairulanuar, Samsudin; Nazre, Abd Rashid; Jamilah, H.; Sairabanu, Omar Khan; Norasikin, Fabil
2010-01-01
This article reports the findings of an experimental study involving 36 primary school students (16 girls, 20 boys, Mean age = 9.5 years, age range: 8-10 years) in geometrical understanding of 2D and 3D objects. Students were assigned into two experimental groups and one control group based on a stratified random sampling procedure. The first…
ERIC Educational Resources Information Center
Jones, Stephanie M.; Brown, Joshua L.; Hoglund, Wendy L. G.; Aber, J. Lawrence
2010-01-01
Objective: To report experimental impacts of a universal, integrated school-based intervention in social-emotional learning and literacy development on change over 1 school year in 3rd-grade children's social-emotional, behavioral, and academic outcomes. Method: This study employed a school-randomized, experimental design and included 942…
"No Excuses" Charter Schools: A Meta-Analysis of the Experimental Evidence on Student Achievement
ERIC Educational Resources Information Center
Cheng, Albert; Hitt, Collin; Kisida, Brian; Mills, Jonathan N.
2017-01-01
Many most well-known charter schools in the United States use a "No Excuses" approach. We conduct the first meta-analysis of the achievement impacts of No Excuses charter schools, focusing on experimental, lottery-based studies. We estimate that No Excuses charter schools increase student math and literacy achievement by 0.25 and 0.17,…
Kappes Ramirez, Maria Soledad
2018-02-01
An experimental study was performed with undergraduate nursing students in order to determine, between two methodologies, which is the best for learning standard precautions and precautions based on disease transmission mechanisms. Students in the sample are stratified by performance, with the experimental group (49 students) being exposed to self-instruction and clinical simulation on the topic of standard precautions and special precautions according to disease transmission mechanisms. Conventional classes on the same topics were provided to the control group (49 students). The experimental group showed the best performance in the multiple-choice post-test of knowledge (p=0.002) and in the assessment of essay questions (p=0.043), as well as in the evaluation of a simulated scenario, in relation to the control group. This study demonstrates that it is possible to transfer some teaching subjects on the prevention of Healthcare Associated Infections (HAIs) to self-learning by means of virtual teaching strategies with good results. This allows greater efficiency in the allocation of teachers to clinical simulation or learning situations in the laboratory, where students can apply what they have learned in the self-instruction module. Copyright © 2017 Elsevier Ltd. All rights reserved.
Xie, Weizhen; Zhang, Weiwei
2017-11-01
The present study dissociated the number (i.e., quantity) and precision (i.e., quality) of visual short-term memory (STM) representations in change detection using receiver operating characteristic (ROC) and experimental manipulations. Across three experiments, participants performed both recognition and recall tests of visual STM using the change-detection task and the continuous color-wheel recall task, respectively. Experiment 1 demonstrated that the estimates of the number and precision of visual STM representations based on the ROC model of change-detection performance were robustly correlated with the corresponding estimates based on the mixture model of continuous-recall performance. Experiments 2 and 3 showed that the experimental manipulation of mnemonic precision using white-noise masking and the experimental manipulation of the number of encoded STM representations using consolidation masking produced selective effects on the corresponding measures of mnemonic precision and the number of encoded STM representations, respectively, in both change-detection and continuous-recall tasks. Altogether, using the individual-differences (Experiment 1) and experimental dissociation (Experiment 2 and 3) approaches, the present study demonstrated the some-or-none nature of visual STM representations across recall and recognition.
NASA Astrophysics Data System (ADS)
Lu, Zheng; Chen, Xiaoyi; Zhou, Ying
2018-04-01
A particle tuned mass damper (PTMD) is a creative combination of a widely used tuned mass damper (TMD) and an efficient particle damper (PD) in the vibration control area. The performance of a one-storey steel frame attached with a PTMD is investigated through free vibration and shaking table tests. The influence of some key parameters (filling ratio of particles, auxiliary mass ratio, and particle density) on the vibration control effects is investigated, and it is shown that the attenuation level significantly depends on the filling ratio of particles. According to the experimental parametric study, some guidelines for optimization of the PTMD that mainly consider the filling ratio are proposed. Furthermore, an approximate analytical solution based on the concept of an equivalent single-particle damper is proposed, and it shows satisfied agreement between the simulation and experimental results. This simplified method is then used for the preliminary optimal design of a PTMD system, and a case study of a PTMD system attached to a five-storey steel structure following this optimization process is presented.
Voga, G P; Coelho, M G; de Lima, G M; Belchior, J C
2011-04-07
In this paper we report experimental and theoretical studies concerning the thermal behavior of some organotin-Ti(IV) oxides employed as precursors for TiO(2)/SnO(2) semiconducting based composites, with photocatalytic properties. The organotin-TiO(2) supported materials were obtained by chemical reactions of SnBu(3)Cl (Bu = butyl), TiCl(4) with NH(4)OH in ethanol, in order to impregnate organotin oxide in a TiO(2) matrix. A theoretical model was developed to support experimental procedures. The kinetics parameters: frequency factor (A), activation energy, and reaction order (n) can be estimated through artificial intelligence methods. Genetic algorithm, fuzzy logic, and Petri neural nets were used in order to determine the kinetic parameters as a function of temperature. With this in mind, three precursors were prepared in order to obtain composites with Sn/TiO(2) ratios of 0% (1), 15% (2), and 30% (3) in weight, respectively. The thermal behavior of products (1-3) was studied by thermogravimetric experiments in oxygen.
Ruel, Jean; Lachance, Geneviève
2010-01-01
This paper presents an experimental study of three bioreactor configurations. The bioreactor is intended to be used for the development of tissue-engineered heart valve substitutes. Therefore it must be able to reproduce physiological flow and pressure waveforms accurately. A detailed analysis of three bioreactor arrangements is presented using mathematical models based on the windkessel (WK) approach. First, a review of the many applications of this approach in medical studies enhances its fundamental nature and its usefulness. Then the models are developed with reference to the actual components of the bioreactor. This study emphasizes different conflicting issues arising in the design process of a bioreactor for biomedical purposes, where an optimization process is essential to reach a compromise satisfying all conditions. Two important aspects are the need for a simple system providing ease of use and long-term sterility, opposed to the need for an advanced (thus more complex) architecture capable of a more accurate reproduction of the physiological environment. Three classic WK architectures are analyzed, and experimental results enhance the advantages and limitations of each one. PMID:21977286