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Sample records for experimental pretest-posttest control

  1. A More Rigorous Quasi-Experimental Alternative to the One-Group Pretest-Posttest Design.

    ERIC Educational Resources Information Center

    Johnson, Craig W.

    1986-01-01

    A simple quasi-experimental design is described which may have utility in a variety of applied and laboratory research settings where ordinarily the one-group pretest-posttest pre-experimental design might otherwise be the procedure of choice. The design approaches the internal validity of true experimental designs while optimizing external…

  2. Impact of a Healthy Nails Program on Nail-Biting in Turkish Schoolchildren: A Controlled Pretest-Posttest Study

    ERIC Educational Resources Information Center

    Ergun, Ayse; Toprak, Rumeysa; Sisman, Fatma Nevin

    2013-01-01

    This study was conducted to examine the effect of a healthy nails program on nail-biting in Turkish schoolchildren. This quasi-experimental study was of pretest-posttest control group design. A total of 50 students of a primary school formed the intervention group, while 53 students from the same school formed the control group. Data were…

  3. Comparing models of change to estimate the mediated effect in the pretest-posttest control group design

    PubMed Central

    Valente, Matthew J.; MacKinnon, David P.

    2017-01-01

    Models to assess mediation in the pretest-posttest control group design are understudied in the behavioral sciences even though it is the design of choice for evaluating experimental manipulations. The paper provides analytical comparisons of the four most commonly used models used to estimate the mediated effect in this design: Analysis of Covariance (ANCOVA), difference score, residualized change score, and cross-sectional model. Each of these models are fitted using a Latent Change Score specification and a simulation study assessed bias, Type I error, power, and confidence interval coverage of the four models. All but the ANCOVA model make stringent assumptions about the stability and cross-lagged relations of the mediator and outcome that may not be plausible in real-world applications. When these assumptions do not hold, Type I error and statistical power results suggest that only the ANCOVA model has good performance. The four models are applied to an empirical example. PMID:28845097

  4. Comparing models of change to estimate the mediated effect in the pretest-posttest control group design.

    PubMed

    Valente, Matthew J; MacKinnon, David P

    2017-01-01

    Models to assess mediation in the pretest-posttest control group design are understudied in the behavioral sciences even though it is the design of choice for evaluating experimental manipulations. The paper provides analytical comparisons of the four most commonly used models used to estimate the mediated effect in this design: Analysis of Covariance (ANCOVA), difference score, residualized change score, and cross-sectional model. Each of these models are fitted using a Latent Change Score specification and a simulation study assessed bias, Type I error, power, and confidence interval coverage of the four models. All but the ANCOVA model make stringent assumptions about the stability and cross-lagged relations of the mediator and outcome that may not be plausible in real-world applications. When these assumptions do not hold, Type I error and statistical power results suggest that only the ANCOVA model has good performance. The four models are applied to an empirical example.

  5. Impact of a healthy nails program on nail-biting in Turkish schoolchildren: a controlled pretest-posttest study.

    PubMed

    Ergun, Ayse; Toprak, Rumeysa; Sisman, Fatma Nevin

    2013-12-01

    This study was conducted to examine the effect of a healthy nails program on nail-biting in Turkish schoolchildren. This quasi-experimental study was of pretest-posttest control group design. A total of 50 students of a primary school formed the intervention group, while 53 students from the same school formed the control group. Data were collected with a demographic form, a nail-biting follow-up form, and photographs of the fingernails. It was found that 68.9% of students were biting seven or more of their nails; 46.6% had damaged nail beds. In the intervention group, the rate of the children who were not biting their nails (baseline = 0%, 4th week = 56.0%, 8th week = 64.0%) increased significantly compared to the control group (baseline = 0%, 4th week = 15.1%, 8th week = 18.9%). Outcomes indicate the efficacy of the healthy nails program in reducing the nail-biting problem in schoolchildren.

  6. Analyzing Data from a Pretest-Posttest Control Group Design: The Importance of Statistical Assumptions

    ERIC Educational Resources Information Center

    Zientek, Linda; Nimon, Kim; Hammack-Brown, Bryn

    2016-01-01

    Purpose: Among the gold standards in human resource development (HRD) research are studies that test theoretically developed hypotheses and use experimental designs. A somewhat typical experimental design would involve collecting pretest and posttest data on individuals assigned to a control or experimental group. Data from such a design that…

  7. Social Stories: Mechanisms of Effectiveness in Increasing Game Play Skills in Children Diagnosed with Autism Spectrum Disorder Using a Pretest Posttest Repeated Measures Randomized Control Group Design

    ERIC Educational Resources Information Center

    Quirmbach, Linda M.; Lincoln, Alan J.; Feinberg-Gizzo, Monica J.; Ingersoll, Brooke R.; Andrews, Siri M.

    2009-01-01

    An increasing body of literature has indicated that social stories are an effective way to teach individuals diagnosed with autism appropriate social behavior. This study compared two formats of a social story targeting the improvement of social skills during game play using a pretest posttest repeated measures randomized control group design. A…

  8. Supporting Staff to Identify Residents in Pain: A Controlled Pretest-Posttest Study in Residential Aged Care.

    PubMed

    Douglas, Clint; Haydon, Deborah; Wollin, Judy

    2016-02-01

    Practical strategies are needed to improve pain awareness among aged care staff and promote a systematic approach to pain identification using evidence-based tools. The purpose of this study was to evaluate a pain identification tool for use by nursing and nonprofessional staff in residential aged care facilities (RACFs). A controlled pretest-posttest intervention design was conducted in two RACFs in Brisbane, Australia. Completed surveys were returned by 216 staff and 74 residents at baseline and 218 staff and 94 residents at 3-month follow-up. Chart audits were conducted on 308 residents at baseline and 328 at follow-up. Groups were compared on: (1) staff knowledge and attitudes regarding pain, perceived confidence and skills for pain assessment, and perceived quality of pain management; (2) frequency of pain assessments and use of pain interventions; and (3) residents' perceptions of the quality of pain management. Both groups had high knowledge scores and reported high levels of confidence, skills, and perceived quality of pain management at baseline and follow-up. The intervention group showed significant improvement in routine pain assessment and use of nonpharmacological pain interventions. However, due to unexpected changes in control group conditions, both groups increased episodic pain assessment. Overall, staff believed the intervention was clinically useful and fostered a team approach to pain assessment. We found the introduction of pain identification resources with implementation strategies to support frontline staff was partially effective in improving staff and resident outcomes. Nonetheless, our findings confirm the need for change and importance of translational pain research in RACFs. Copyright © 2016 American Society for Pain Management Nursing. Published by Elsevier Inc. All rights reserved.

  9. Efficacy of the Get Ready to Learn yoga program among children with autism spectrum disorders: a pretest-posttest control group design.

    PubMed

    Koenig, Kristie Patten; Buckley-Reen, Anne; Garg, Satvika

    2012-01-01

    Occupational therapists use school-based yoga programs, but these interventions typically lack manualization and evidence from well-designed studies. Using an experimental pretest-posttest control group design, we examined the effectiveness of the Get Ready to Learn (GRTL) classroom yoga program among children with autism spectrum disorders (ASD). The intervention group received the manualized yoga program daily for 16 wk, and the control group engaged in their standard morning routine. We assessed challenging behaviors with standardized measures and behavior coding before and after intervention. We completed a between-groups analysis of variance to assess differences in gain scores on the dependent variables. Students in the GRTL program showed significant decreases (p < .05) in teacher ratings of maladaptive behavior, as measured with the Aberrant Behavior Checklist, compared with the control participants. This study demonstrates that use of daily classroomwide yoga interventions has a significant impact on key classroom behaviors among children with ASD. Copyright © 2012 by the American Occupational Therapy Association, Inc.

  10. Social stories: mechanisms of effectiveness in increasing game play skills in children diagnosed with autism spectrum disorder using a pretest posttest repeated measures randomized control group design.

    PubMed

    Quirmbach, Linda M; Lincoln, Alan J; Feinberg-Gizzo, Monica J; Ingersoll, Brooke R; Andrews, Siri M

    2009-02-01

    An increasing body of literature has indicated that social stories are an effective way to teach individuals diagnosed with autism appropriate social behavior. This study compared two formats of a social story targeting the improvement of social skills during game play using a pretest posttest repeated measures randomized control group design. A total of 45 children diagnosed with Autism Spectrum Disorder (ASD) ages 7-14 were randomly assigned to standard, directive, or control story conditions. Results demonstrated that the standard and directive story formats were equally as effective in eliciting, generalizing and maintaining the targeted social skills in participants who had prior game play experience and Verbal Comprehension Index (VCI) scores from the WISC-IV intelligence test in the borderline range or above.

  11. Supporting of the Fathers to Visit Their Infants in Neonatal Intensive Care Unit Decreases Their Stress Level: A Pretest-Posttest Quasi-Experimental Study.

    PubMed

    Kardaş Özdemir, Funda; Küçük Alemdar, Dilek

    2017-05-01

    It is known that fathers whose infants are hospitalized in NICUs (Neonatal Intensive Care Units) are severely stressed. This study was conducted for the purpose of determining the effect of supporting and visiting infants in NICUs on stress levels of Turkish fathers. This was a pretest-posttest quasi-experimental study. The population of the study consisted of 47 fathers who had their infants receiving treatment in NICU at a state hospital in the eastern Turkey and agreed to participate in the study. The data were collected by using "Father-Infant Introductory Information Form" and "Parental Stressor Scale: Neonatal Intensive Care Unit, PSS:NICU". When comparing the PSS:NICU total mean scores of the fathers before and after interventions; it was determined that their mean scores were higher before visits compared to those obtained after interventions and the difference between them was significant at advanced level. It was found that the fathers visiting and supporting their infants in NICUs had the decreased stress levels. It is a useful nursing intervention to support fathers to visit their babies in NICUs and establish environments where they could spend time with their babies.

  12. Effects of learning content in context on knowledge acquisition and recall: a pretest-posttest control group design.

    PubMed

    Bergman, Esther M; de Bruin, Anique B H; Vorstenbosch, Marc A T M; Kooloos, Jan G M; Puts, Ghita C W M; Leppink, Jimmie; Scherpbier, Albert J J A; van der Vleuten, Cees P M

    2015-08-15

    It is generally assumed that learning in context increases performance. This study investigates the relationship between the characteristics of a paper-patient context (relevance and familiarity), the mechanisms through which the cognitive dimension of context could improve learning (activation of prior knowledge, elaboration and increasing retrieval cues), and test performance. A total of 145 medical students completed a pretest of 40 questions, of which half were with a patient vignette. One week later, they studied musculoskeletal anatomy in the dissection room without a paper-patient context (control group) or with (ir)relevant-(un)familiar context (experimental groups), and completed a cognitive load scale. Following a short delay, the students completed a posttest. Surprisingly, our results show that students who studied in context did not perform better than students who studied without context. This finding may be explained by an interaction of the participants' expertise level, the nature of anatomical knowledge and students' approaches to learning. A relevant-familiar context only reduced the negative effect of learning the content in context. Our results suggest discouraging the introduction of an uncommon disease to illustrate a basic science concept. Higher self-perceived learning scores predict higher performance. Interestingly, students performed significantly better on the questions with context in both tests, possibly due to a 'framing effect'. Since studies focusing on the physical and affective dimensions of context have also failed to find a positive influence of learning in a clinically relevant context, further research seems necessary to refine our theories around the role of context in learning.

  13. Effects of a back-pain-reducing program during pregnancy for Korean women: a non-equivalent control-group pretest-posttest study.

    PubMed

    Shim, Mi-Jung; Lee, Young-Sook; Oh, Hyun-Ei; Kim, Jin-Sun

    2007-01-01

    Although many pregnant women experience back pain, it has not considered an important health problem. No study has investigated the effects of a back-pain-reducing program (BPRP) during pregnancy for Korean women. The purpose of this study was to evaluate the effect of a program designed to reduce back pain in pregnant women. A non-equivalent control-group pretest-posttest design was used. Pregnant women who attended an antenatal clinic and experienced back pain during their pregnancy were included in an intervention group (n=29), and their intensity of back pain, functional limitation and anxiety were compared with women in a control group from another antenatal clinic (n=27). The data were collected at three time points: prior to intervention, and 6 and 12 weeks after intervention. At 12 weeks after intervention, the intensity of back pain experienced by the intervention group was significantly lower than that of the control group. However, there were no statistically significant differences between the groups with respect to functional limitations and anxiety. The findings show that the pain-reducing program developed for this study was effective in reducing the intensity of back pain experienced by pregnant women. Promoting good posture and regular exercise can be recommended as a method to relieve back pain in pregnancy women. Further studies are needed to confirm the effect of the BPRP during pregnancy.

  14. Evaluation of a caregiver education program to support memory and communication in dementia: a controlled pretest-posttest study with nursing home staff.

    PubMed

    Broughton, Megan; Smith, Erin R; Baker, Rosemary; Angwin, Anthony J; Pachana, Nancy A; Copland, David A; Humphreys, Michael S; Gallois, Cindy; Byrne, Gerard J; Chenery, Helen J

    2011-11-01

    There is a need for simple multimedia training programs designed to upskill the dementia care workforce. A DVD-based training program entitled RECAPS and MESSAGE has been designed to provide caregivers with strategies to support memory and communication in people with dementia. The aims of this study were: (1) to evaluate the effects of the RECAPS and MESSAGE training on knowledge of support strategies, and caregiver satisfaction, in nursing home care staff, and (2) to evaluate staff opinion of the training. A multi-centre controlled pretest-posttest trial was conducted between June 2009 and January 2010, with baseline, immediately post-training and 3-month follow-up assessment. Four nursing homes in Queensland, Australia. All care staff were invited to participate. Of the 68 participants who entered the study, 52 (37 training participants and 15 controls) completed outcome measures at baseline and 3-month follow-up. 63.5% of participants were nursing assistants, 25% were qualified nurses and 11.5% were recreational/activities officers. The training and control groups were compared on the following outcomes: (1) knowledge of memory and communication support strategies, and (2) caregiver satisfaction. In the training group, the immediate effects of training on knowledge, and the effects of role (nurse, nursing assistant, recreational staff) on both outcome measures, were also examined. Staff opinion of the training was assessed immediately post-training and at 3-month follow-up. The training group showed a significant improvement in knowledge of support strategies from baseline to immediately post-training (p=0.001). Comparison of the training and control groups revealed a significant increase in knowledge for the training group (p=0.011), but not for the control group (p=0.33), between baseline and 3-month follow-up. Examination of caregiver satisfaction by care staff role in the training group revealed that only the qualified nurses showed higher levels of

  15. Pilot Intervention to Increase Physical Activity among Sedentary Urban Middle School Girls: A Two-Group Pretest-Posttest Quasi-Experimental Design

    ERIC Educational Resources Information Center

    Robbins, Lorraine B.; Pfeiffer, Karin A.; Maier, Kimberly S.; Lo, Yun-Jia; Wesolek, Stacey M.

    2012-01-01

    The primary purpose of the study was to determine whether girls in one school receiving nurse counseling plus an after-school physical activity club showed greater improvement in physical activity, cardiovascular fitness, and body composition than girls assigned to an attention control condition in another school (N = 69). Linear regressions…

  16. Pilot intervention to increase physical activity among sedentary urban middle school girls: a two-group pretest-posttest quasi-experimental design

    PubMed Central

    Robbins, Lorraine B.; Pfeiffer, Karin A.; Maier, Kimberly S.; Lo, Yun-Jia; Wesolek, Stacey M.

    2012-01-01

    The primary purpose of the study was to determine if girls in one school receiving nurse counseling plus an after-school Physical Activity Club showed greater improvement in physical activity, cardiovascular fitness, and body composition than girls assigned to an attention control condition in another school (N = 69). Linear regressions controlling for baseline measures showed no statistically significant group differences, but directionality of differences was consistent with greater intervention group improvement for minutes of moderate to vigorous physical activity/hour (t = 0.95, p = .35), cardiovascular fitness (t = 1.26, p = .22), body mass index (BMI; t = −1.47, p = .15), BMI z-score (t = −1.19, p = .24), BMI percentile (t = −0.59, p = .56), percent body fat (t = −0.86, p = .39), and waist circumference (t = −0.19, p = .85). Findings support testing with a larger sample. PMID:22472632

  17. Pilot intervention to increase physical activity among sedentary urban middle school girls: a two-group pretest-posttest quasi-experimental design.

    PubMed

    Robbins, Lorraine B; Pfeiffer, Karin A; Maier, Kimberly S; Lo, Yun-Jia; Wesolek Ladrig, Stacey M

    2012-08-01

    The primary purpose of the study was to determine whether girls in one school receiving nurse counseling plus an after-school physical activity club showed greater improvement in physical activity, cardiovascular fitness, and body composition than girls assigned to an attention control condition in another school (N = 69). Linear regressions controlling for baseline measures showed no statistically significant group differences, but the directionality of differences was consistent with greater intervention group improvement for minutes of moderate to vigorous physical activity/hour (t = 0.95, p = .35), cardiovascular fitness (t = 1.26, p = .22), body mass index (BMI; t = -1.47, p = .15), BMI z score (t = -1.19, p = .24), BMI percentile (t = -0.59, p = .56), percentage body fat (t = -0.86, p = .39), and waist circumference (t = -0.19, p = .85). Findings support testing with a larger sample.

  18. Influence of Training on First-Year Nursing Department Students' Attitudes on Death and Caring for Dying Patients: A Single-Group Pretest-Posttest Experimental Study.

    PubMed

    Cerit, Birgül

    2017-01-01

    The study examined the influence of training on first-year nursing department students' attitudes on death and caring for dying patients. Utilizing the experimental model, the study sample consisted of 81 first-year students attending the nursing department of a university. Death Attitude Profile-Revised and Frommelt Attitude toward Care of the Dying Scale were used for data collection. Data analysis included means, standard deviation, and t test for related samples. Student attitudes toward death were measured as 146.43 (16.741) and 152.75 (15.132) for pre- and posttraining, respectively. Student attitudes toward caring for dying patients were established to be 103.02 (7.655) during pretraining period and 111.02 (10.359) at posttraining period. The difference between pre- and posttests for mean attitudes toward death and caring for the dying patient was statistically significant. Study results determined that training was effective in forming positive student attitudes toward death and caring for dying patients.

  19. Efficacy of a care bundle to prevent multiple infections in the intensive care unit: A quasi-experimental pretest-posttest design study.

    PubMed

    Yazici, Gulay; Bulut, Hulya

    2018-02-01

    Healthcare-associated infections extend hospitalization time, increase treatment costs and increase morbidity-mortality rates. To evaluate the efficacy of a care bundle aimed at preventing three most frequent intensive care unit-acquired infections. This quasi-experimental study occurred in an 18-bed tertiary care intensive care unit at a university hospital in Turkey. The sample consisted of 120 patients older than 18years and receiving invasive mechanical ventilation therapy, or had a central venous catheter or urinary catheter. The study comprised three stages. In stage one, the intensive care unit nurses were trained in infection measures, VAP, CA-UTIs and CLABSIs sections of the care bundle. In stage two, the trained nurses applied the care bundle and received feedback on any problematic issues. In stage three, the nurses' compatibility and efficacy of the infection prevention care bundle on the infection rates of VAP, CA-UTIs and CLABSIs were evaluated over three 3-month periods. Over 1000 ventilation days, ventilator-associated pneumonia infection rates were 23.4, 12.6, and 11.5, during January-March, April-June and July-September, respectively, with January-March and April-June showing a significant decrease (χ 2 =6.934, p=0.031). The central line-associated bloodstream infection rates were 8.9, 4.2, and 9.9 per 1000 catheter days, during January-March, April-June and July-September, respectively, but were not significantly different based on pair-wise comparisons (p>0.05). The catheter-associated urinary tract infection rates were higher during July-September (6.7/1000 catheter days) compared to January-March (5.7/1000 catheter days) and April-June (10.4/1000 catheter days) but the differences were not significant (p>0.05). The infection rates decreased with increased compatibility of the care bundle prepared from evidence-based guidelines. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Pretest-posttest designs and measurement of change.

    PubMed

    Dimitrov, Dimiter M; Rumrill, Phillip D

    2003-01-01

    The article examines issues involved in comparing groups and measuring change with pretest and posttest data. Different pretest-posttest designs are presented in a manner that can help rehabilitation professionals to better understand and determine effects resulting from selected interventions. The reliability of gain scores in pretest-posttest measurement is also discussed in the context of rehabilitation research and practice.

  1. Effects of video-feedback on the communication, clinical competence and motivational interviewing skills of practice nurses: a pre-test posttest control group study.

    PubMed

    Noordman, Janneke; van der Weijden, Trudy; van Dulmen, Sandra

    2014-10-01

    To examine the effects of individual video-feedback on the generic communication skills, clinical competence (i.e. adherence to practice guidelines) and motivational interviewing skills of experienced practice nurses working in primary care. Continuing professional education may be necessary to refresh and reflect on the communication and motivational interviewing skills of experienced primary care practice nurses. A video-feedback method was designed to improve these skills. Pre-test/posttest control group design. Seventeen Dutch practice nurses and 325 patients participated between June 2010-June 2011. Nurse-patient consultations were videotaped at two moments (T0 and T1), with an interval of 3-6 months. The videotaped consultations were rated using two protocols: the Maastrichtse Anamnese en Advies Scorelijst met globale items (MAAS-global) and the Behaviour Change Counselling Index. Before the recordings, nurses were allocated to a control or video-feedback group. Nurses allocated to the video-feedback group received video-feedback between T0 and T1. Data were analysed using multilevel linear or logistic regression. Nurses who received video-feedback appeared to pay significantly more attention to patients' request for help, their physical examination and gave significantly more understandable information. With respect to motivational interviewing, nurses who received video-feedback appeared to pay more attention to 'agenda setting and permission seeking' during their consultations. Video-feedback is a potentially effective method to improve practice nurses' generic communication skills. Although a single video-feedback session does not seem sufficient to increase all motivational interviewing skills, significant improvement in some specific skills was found. Nurses' clinical competences were not altered after feedback due to already high standards. © 2014 John Wiley & Sons Ltd.

  2. Comparing Feedback Types in Multimedia Learning of Speech by Young Children With Common Speech Sound Disorders: Research Protocol for a Pretest Posttest Independent Measures Control Trial.

    PubMed

    Doubé, Wendy; Carding, Paul; Flanagan, Kieran; Kaufman, Jordy; Armitage, Hannah

    2018-01-01

    Children with speech sound disorders benefit from feedback about the accuracy of sounds they make. Home practice can reinforce feedback received from speech pathologists. Games in mobile device applications could encourage home practice, but those currently available are of limited value because they are unlikely to elaborate "Correct"/"Incorrect" feedback with information that can assist in improving the accuracy of the sound. This protocol proposes a "Wizard of Oz" experiment that aims to provide evidence for the provision of effective multimedia feedback for speech sound development. Children with two common speech sound disorders will play a game on a mobile device and make speech sounds when prompted by the game. A human "Wizard" will provide feedback on the accuracy of the sound but the children will perceive the feedback as coming from the game. Groups of 30 young children will be randomly allocated to one of five conditions: four types of feedback and a control which does not play the game. The results of this experiment will inform not only speech sound therapy, but also other types of language learning, both in general, and in multimedia applications. This experiment is a cost-effective precursor to the development of a mobile application that employs pedagogically and clinically sound processes for speech development in young children.

  3. Comparing Feedback Types in Multimedia Learning of Speech by Young Children With Common Speech Sound Disorders: Research Protocol for a Pretest Posttest Independent Measures Control Trial

    PubMed Central

    Doubé, Wendy; Carding, Paul; Flanagan, Kieran; Kaufman, Jordy; Armitage, Hannah

    2018-01-01

    Children with speech sound disorders benefit from feedback about the accuracy of sounds they make. Home practice can reinforce feedback received from speech pathologists. Games in mobile device applications could encourage home practice, but those currently available are of limited value because they are unlikely to elaborate “Correct”/”Incorrect” feedback with information that can assist in improving the accuracy of the sound. This protocol proposes a “Wizard of Oz” experiment that aims to provide evidence for the provision of effective multimedia feedback for speech sound development. Children with two common speech sound disorders will play a game on a mobile device and make speech sounds when prompted by the game. A human “Wizard” will provide feedback on the accuracy of the sound but the children will perceive the feedback as coming from the game. Groups of 30 young children will be randomly allocated to one of five conditions: four types of feedback and a control which does not play the game. The results of this experiment will inform not only speech sound therapy, but also other types of language learning, both in general, and in multimedia applications. This experiment is a cost-effective precursor to the development of a mobile application that employs pedagogically and clinically sound processes for speech development in young children. PMID:29674986

  4. Why Is the One-Group Pretest-Posttest Design Still Used?

    PubMed

    Knapp, Thomas R

    2016-10-01

    The one-group pretest-posttest pre-experimental design has been widely criticized, yet continues to be used in some clinical nursing research studies. This editorial explains what is wrong with the design, suggests reasons for its continued use, and gives some recommendations regarding what can be done about it. © The Author(s) 2016.

  5. Measuring Student Learning in Social Statistics: A Pretest-Posttest Study of Knowledge Gain

    ERIC Educational Resources Information Center

    Delucchi, Michael

    2014-01-01

    This study used a pretest-posttest design to measure student learning in undergraduate statistics. Data were derived from 185 students enrolled in six different sections of a social statistics course taught over a seven-year period by the same sociology instructor. The pretest-posttest instrument reveals statistically significant gains in…

  6. Evaluation of a real world intervention using professional football players to promote a healthy diet and physical activity in children and adolescents from a lower socio-economic background: a controlled pretest-posttest design.

    PubMed

    Dubuy, Veerle; De Cocker, Katrien; De Bourdeaudhuij, Ilse; Maes, Lea; Seghers, Jan; Lefevre, Johan; De Martelaer, Kristine; Brooke, Hannah; Cardon, Greet

    2014-05-16

    The increasing rates of obesity among children and adolescents, especially in those from lower socio-economic backgrounds, emphasise the need for interventions promoting a healthy diet and physical activity. The present study aimed to examine the effectiveness of the 'Health Scores!' program, which combined professional football player role models with a school-based program to promote a healthy diet and physical activity to socially vulnerable children and adolescents. The intervention was implemented in two settings: professional football clubs and schools. Socially vulnerable children and adolescents (n = 165 intervention group, n = 440 control group, aged 10-14 year) provided self-reported data on dietary habits and physical activity before and after the four-month intervention. Intervention effects were evaluated using repeated measures analysis of variance. In addition, a process evaluation was conducted. No intervention effects were found for several dietary behaviours, including consumption of breakfast, fruit, soft drinks or sweet and savoury snacks. Positive intervention effects were found for self-efficacy for having a daily breakfast (p < 0.01), positive attitude towards vegetables consumption (p < 0.01) and towards lower soft drink consumption (p < 0.001). A trend towards significance (p < 0.10) was found for self-efficacy for reaching the physical activity guidelines. For sports participation no significant intervention effect was found. In total, 92 pupils completed the process evaluation, the feedback was largely positive. The 'Health Scores!' intervention was successful in increasing psychosocial correlates of a healthy diet and PA. The use of professional football players as a credible source for health promotion was appealing to socially vulnerable children and adolescents.

  7. Statistical power for nonequivalent pretest-posttest designs. The impact of change-score versus ANCOVA models.

    PubMed

    Oakes, J M; Feldman, H A

    2001-02-01

    Nonequivalent controlled pretest-posttest designs are central to evaluation science, yet no practical and unified approach for estimating power in the two most widely used analytic approaches to these designs exists. This article fills the gap by presenting and comparing useful, unified power formulas for ANCOVA and change-score analyses, indicating the implications of each on sample-size requirements. The authors close with practical recommendations for evaluators. Mathematical details and a simple spreadsheet approach are included in appendices.

  8. Intermanual transfer in training with an upper-limb myoelectric prosthesis simulator: a mechanistic, randomized, pretest-posttest study.

    PubMed

    Romkema, Sietske; Bongers, Raoul M; van der Sluis, Corry K

    2013-01-01

    Intermanual transfer may improve prosthetic handling and acceptance if used in training soon after an amputation. The purpose of this study was to determine whether intermanual transfer effects can be detected after training with a myoelectric upper-limb prosthesis simulator. A mechanistic, randomized, pretest-posttest design was used. A total of 48 right-handed participants (25 women, 23 men) who were able-bodied were randomly assigned to an experimental group or a control group. The experimental group performed a training program of 5 days' duration using the prosthesis simulator. To determine the improvement in skill, a test was administered before, immediately after, and 6 days after training. The control group only performed the tests. Training was performed with the unaffected arm, and tests were performed with the affected arm (the affected arm simulating an amputated limb). Half of the participants were tested with the dominant arm and half with the nondominant arm. Initiation time was defined as the time from starting signal until start of the movement, movement time was defined as the time from the beginning of the movement until completion of the task, and force control was defined as the maximal applied force on a deformable object. The movement time decreased significantly more in the experimental group (F₂,₉₂=7.42, P=.001, η²(G)=.028) when compared with the control group. This finding is indicative of faster handling of the prosthesis. No statistically significant differences were found between groups with regard to initiation time and force control. We did not find a difference in intermanual transfer between the dominant and nondominant arms. The training utilized participants who were able-bodied in a laboratory setting and focused only on transradial amputations. Intermanual transfer was present in the affected arm after training the unaffected arm with a myoelectric prosthesis simulator, and this effect did not depend on laterality. This

  9. Intermanual transfer effect in young children after training in a complex skill: mechanistic, pseudorandomized, pretest-posttest study.

    PubMed

    Romkema, Sietske; Bongers, Raoul M; van der Sluis, Corry K

    2015-05-01

    Intermanual transfer implies that motor skills learned on one side of the body transfer to the untrained side. This effect was previously noted in adults practicing with a prosthesis simulator. The study objective was to determine whether intermanual transfer is present in children practicing prosthetic handling. A mechanistic, pseudorandomized, pretest-posttest design was used. The study was conducted in a primary school in the Netherlands. The participants were children who were able-bodied (N=48; 25 boys, 23 girls; mean age=5.1 years) and randomly assigned to an experimental group or a control group. The experimental group performed 5 training sessions using a prosthesis simulator on the training arm. Before (pretest), immediately after (posttest), and 6 days after (retention test) the training program, their ability to handle the prosthesis with the contralateral (test) arm was measured. The control group only performed the tests. Half of the children performed the tests with the dominant hand, and the other half performed the tests with the nondominant hand. During the tests, movement time and control of force were measured. An interaction effect of group by test was found for movement time. Post hoc tests revealed significant improvement in the experimental group between the posttest and the retention test. No force control effect was found. Only children who were able-bodied were included. Measurements should have been masked and obtained without tester interference. The fact that 4 children whose results were slower than the mean result discontinued training may have biased the findings. The intermanual transfer effect was present in 5-year-old children undergoing training in prosthetic handling. After training of one hand, children's movement times for the other, untrained hand improved. This finding may be helpful for training children who are novice users of a prosthesis. © 2015 American Physical Therapy Association.

  10. The Importance of Longitudinal Pretest-Posttest Designs in Estimating College Impact

    ERIC Educational Resources Information Center

    Seifert, Tricia A.; Pascarella, Ernest T.; Erkel, Sherri I.; Goodman, Kathleen M.

    2010-01-01

    In this chapter, the authors discuss the issue of research design in conducting inquiry on college impact and demonstrate the importance of longitudinal pretest-posttest designs in maximizing the internal validity of findings. They begin by discussing the strengths and weaknesses of different types of research design in the college impact…

  11. Some unexamined aspects of analysis of covariance in pretest-posttest studies.

    PubMed

    Ganju, Jitendra

    2004-09-01

    The use of an analysis of covariance (ANCOVA) model in a pretest-posttest setting deserves to be studied separately from its use in other (non-pretest-posttest) settings. For pretest-posttest studies, the following points are made in this article: (a) If the familiar change from baseline model accurately describes the data-generating mechanism for a randomized study then it is impossible for unequal slopes to exist. Conversely, if unequal slopes exist, then it implies that the change from baseline model as a data-generating mechanism is inappropriate. An alternative data-generating model should be identified and the validity of the ANCOVA model should be demonstrated. (b) Under the usual assumptions of equal pretest and posttest within-subject error variances, the ratio of the standard error of a treatment contrast from a change from baseline analysis to that from ANCOVA is less than 2(1)/(2). (c) For an observational study it is possible for unequal slopes to exist even if the change from baseline model describes the data-generating mechanism. (d) Adjusting for the pretest variable in observational studies may actually introduce bias where none previously existed.

  12. Empirical Likelihood-Based Estimation of the Treatment Effect in a Pretest-Posttest Study.

    PubMed

    Huang, Chiung-Yu; Qin, Jing; Follmann, Dean A

    2008-09-01

    The pretest-posttest study design is commonly used in medical and social science research to assess the effect of a treatment or an intervention. Recently, interest has been rising in developing inference procedures that improve efficiency while relaxing assumptions used in the pretest-posttest data analysis, especially when the posttest measurement might be missing. In this article we propose a semiparametric estimation procedure based on empirical likelihood (EL) that incorporates the common baseline covariate information to improve efficiency. The proposed method also yields an asymptotically unbiased estimate of the response distribution. Thus functions of the response distribution, such as the median, can be estimated straightforwardly, and the EL method can provide a more appealing estimate of the treatment effect for skewed data. We show that, compared with existing methods, the proposed EL estimator has appealing theoretical properties, especially when the working model for the underlying relationship between the pretest and posttest measurements is misspecified. A series of simulation studies demonstrates that the EL-based estimator outperforms its competitors when the working model is misspecified and the data are missing at random. We illustrate the methods by analyzing data from an AIDS clinical trial (ACTG 175).

  13. Semiparametric Estimation of Treatment Effect in a Pretest-Posttest Study with Missing Data.

    PubMed

    Davidian, Marie; Tsiatis, Anastasios A; Leon, Selene

    2005-08-01

    The pretest-posttest study is commonplace in numerous applications. Typically, subjects are randomized to two treatments, and response is measured at baseline, prior to intervention with the randomized treatment (pretest), and at prespecified follow-up time (posttest). Interest focuses on the effect of treatments on the change between mean baseline and follow-up response. Missing posttest response for some subjects is routine, and disregarding missing cases can lead to invalid inference. Despite the popularity of this design, a consensus on an appropriate analysis when no data are missing, let alone for taking into account missing follow-up, does not exist. Under a semiparametric perspective on the pretest-posttest model, in which limited distributional assumptions on pretest or posttest response are made, we show how the theory of Robins, Rotnitzky and Zhao may be used to characterize a class of consistent treatment effect estimators and to identify the efficient estimator in the class. We then describe how the theoretical results translate into practice. The development not only shows how a unified framework for inference in this setting emerges from the Robins, Rotnitzky and Zhao theory, but also provides a review and demonstration of the key aspects of this theory in a familiar context. The results are also relevant to the problem of comparing two treatment means with adjustment for baseline covariates.

  14. Analytic methods for questions pertaining to a randomized pretest, posttest, follow-up design.

    PubMed

    Rausch, Joseph R; Maxwell, Scott E; Kelley, Ken

    2003-09-01

    Delineates 5 questions regarding group differences that are likely to be of interest to researchers within the framework of a randomized pretest, posttest, follow-up (PPF) design. These 5 questions are examined from a methodological perspective by comparing and discussing analysis of variance (ANOVA) and analysis of covariance (ANCOVA) methods and briefly discussing hierarchical linear modeling (HLM) for these questions. This article demonstrates that the pretest should be utilized as a covariate in the model rather than as a level of the time factor or as part of the dependent variable within the analysis of group differences. It is also demonstrated that how the posttest and the follow-up are utilized in the analysis of group differences is determined by the specific question asked by the researcher.

  15. Semiparametric estimation of treatment effect in a pretest-posttest study.

    PubMed

    Leon, Selene; Tsiatis, Anastasios A; Davidian, Marie

    2003-12-01

    Inference on treatment effects in a pretest-posttest study is a routine objective in medicine, public health, and other fields. A number of approaches have been advocated. We take a semiparametric perspective, making no assumptions about the distributions of baseline and posttest responses. By representing the situation in terms of counterfactual random variables, we exploit recent developments in the literature on missing data and causal inference, to derive the class of all consistent treatment effect estimators, identify the most efficient such estimator, and outline strategies for implementation of estimators that may improve on popular methods. We demonstrate the methods and their properties via simulation and by application to a data set from an HIV clinical trial.

  16. Innovations for Evaluation Research: Multiform Protocols, Visual Analog Scaling, and the Retrospective Pretest-Posttest Design.

    PubMed

    Chang, Rong; Little, Todd D

    2018-06-01

    In this article, we review three innovative methods: multiform protocols, visual analog scaling, and the retrospective pretest-posttest design that can be used in evaluation research. These three techniques have been proposed for decades, but unfortunately, they are still not utilized readily in evaluation research. Our goal is to familiarize researchers with these underutilized research techniques that could reduce personnel effort and costs for data collection while producing better inferences for a study. We begin by discussing their applications and special unique features. We then discuss each technique's strengths and limitations and offer practical tips on how to better implement these methods in evaluation research. We then showcase two recent empirical studies that implement these methods in real-world evaluation research applications.

  17. Evaluating Community Health Advisor (CHA) Core Competencies: The CHA Core Competency Retrospective Pretest/Posttest (CCCRP).

    PubMed

    Story, Lachel; To, Yen M

    2016-05-01

    Health care and academic systems are increasingly collaborating with community health advisors (CHAs) to provide culturally relevant health interventions that promote sustained community transformation. Little attention has been placed on CHA training evaluation, including core competency attainment. This study identified common CHA core competencies, generated a theoretically based measure of those competencies, and explored psychometric properties of that measure. A concept synthesis revealed five CHA core competencies (leadership, translation, guidance, advocacy, and caring). The CHA Core Competency Retrospective Pretest/Posttest (CCCRP) resulted from that synthesis, which was administered using multiple approaches to individuals who previously received CHA training (N= 142). Exploratory factor analyses revealed a two-factor structure underlying the posttraining data, and Cronbach's alpha indicated high internal consistency. This study suggested some CHA core competencies might be more interrelated than previously thought, and two major competencies exist rather than five and supported the CCCRP's use to evaluate core competency attainment resulting from training. © The Author(s) 2014.

  18. Evaluating Intervention Programs with a Pretest-Posttest Design: A Structural Equation Modeling Approach

    PubMed Central

    Alessandri, Guido; Zuffianò, Antonio; Perinelli, Enrico

    2017-01-01

    A common situation in the evaluation of intervention programs is the researcher's possibility to rely on two waves of data only (i.e., pretest and posttest), which profoundly impacts on his/her choice about the possible statistical analyses to be conducted. Indeed, the evaluation of intervention programs based on a pretest-posttest design has been usually carried out by using classic statistical tests, such as family-wise ANOVA analyses, which are strongly limited by exclusively analyzing the intervention effects at the group level. In this article, we showed how second order multiple group latent curve modeling (SO-MG-LCM) could represent a useful methodological tool to have a more realistic and informative assessment of intervention programs with two waves of data. We offered a practical step-by-step guide to properly implement this methodology, and we outlined the advantages of the LCM approach over classic ANOVA analyses. Furthermore, we also provided a real-data example by re-analyzing the implementation of the Young Prosocial Animation, a universal intervention program aimed at promoting prosociality among youth. In conclusion, albeit there are previous studies that pointed to the usefulness of MG-LCM to evaluate intervention programs (Muthén and Curran, 1997; Curran and Muthén, 1999), no previous study showed that it is possible to use this approach even in pretest-posttest (i.e., with only two time points) designs. Given the advantages of latent variable analyses in examining differences in interindividual and intraindividual changes (McArdle, 2009), the methodological and substantive implications of our proposed approach are discussed. PMID:28303110

  19. Evaluating Intervention Programs with a Pretest-Posttest Design: A Structural Equation Modeling Approach.

    PubMed

    Alessandri, Guido; Zuffianò, Antonio; Perinelli, Enrico

    2017-01-01

    A common situation in the evaluation of intervention programs is the researcher's possibility to rely on two waves of data only (i.e., pretest and posttest), which profoundly impacts on his/her choice about the possible statistical analyses to be conducted. Indeed, the evaluation of intervention programs based on a pretest-posttest design has been usually carried out by using classic statistical tests, such as family-wise ANOVA analyses, which are strongly limited by exclusively analyzing the intervention effects at the group level. In this article, we showed how second order multiple group latent curve modeling (SO-MG-LCM) could represent a useful methodological tool to have a more realistic and informative assessment of intervention programs with two waves of data. We offered a practical step-by-step guide to properly implement this methodology, and we outlined the advantages of the LCM approach over classic ANOVA analyses. Furthermore, we also provided a real-data example by re-analyzing the implementation of the Young Prosocial Animation, a universal intervention program aimed at promoting prosociality among youth. In conclusion, albeit there are previous studies that pointed to the usefulness of MG-LCM to evaluate intervention programs (Muthén and Curran, 1997; Curran and Muthén, 1999), no previous study showed that it is possible to use this approach even in pretest-posttest (i.e., with only two time points) designs. Given the advantages of latent variable analyses in examining differences in interindividual and intraindividual changes (McArdle, 2009), the methodological and substantive implications of our proposed approach are discussed.

  20. Effect of a coteaching handwriting program for first graders: one-group pretest-posttest design.

    PubMed

    Case-Smith, Jane; Holland, Terri; Lane, Alison; White, Susan

    2012-01-01

    We examined the effects of a cotaught handwriting and writing program on first-grade students grouped by low, average, and high baseline legibility. The program's aim was to increase legibility, handwriting speed, writing fluency, and written expression in students with diverse learning needs. Thirty-six first-grade students in two classrooms participated in a 12-wk handwriting and writing program cotaught by teachers and an occupational therapist. Students were assessed at pretest, posttest, and 6-mo follow-up using the Evaluation Tool of Children's Handwriting-Manuscript (ETCH-M) and the Woodcock-Johnson Writing Fluency and Writing Samples tests. Students made large gains in ETCH-M legibility (η² = .74), speed (η²s = .52-.65), Writing Fluency (η² = .58), and Writing Samples (η² = .59). Students with initially low legibility improved most in legibility; progress on the other tests was similar across low-, average-, and high-performing groups. This program appeared to benefit first-grade students with diverse learning needs and to increase handwriting legibility and speed and writing fluency. Copyright © 2012 by the American Occupational Therapy Association, Inc.

  1. of nurses from an acute care hospital: a pretest-posttest-study

    PubMed

    Evers, Eva; Hahn, Sabine; Metzenthin, Petra

    2018-01-24

    Background: Harmful alcohol consumption is associated with approximately 1600 deaths in Switzerland annually, and is the third-largest risk factor for various diseases worldwide. It has been shown that through early identification of problematic drinking behaviours along with preventive intervention, alcohol-related illnesses and mortality can be reduced. Therefore, nurses play a crucial role for patients with alcohol problems. However, the most common reasons for nurses not providing preventive intervention are a lack of knowledge, personal attitudes and uncertainty. Learning programs hold the potential for influencing these factors. Aim: The aim of this study was to assess the impact of an e-learning program regarding patients’ harmful alcohol consumption on the knowledge, attitudes and perceived competencies of nurses in an acute care hospital. Method: A pretest-posttest-study was conducted with 33 registered nurses prior to and upon completion of the e-learning program. Data was collected from December 2013 to March 2014 using a literature-based questionnaire. Results: It was shown that knowledge and perceived competencies significantly improved from pre-test to post-test. No significant differences were measured with regard to the attitudes. Conclusions: The results suggest that the alcohol e-learning program could be used to enhance nurses’ knowledge and perceived competencies, both of which are related to the reduction of uncertainty and improvement of confidence. To foster non-judgemental attitudes towards affected people, classroom courses are recommended in addition to the e-learning program and the implementation of directives.

  2. The Log Handwriting Program improved children's writing legibility: a pretest-posttest study.

    PubMed

    Mackay, Nadine; McCluskey, Annie; Mayes, Rachel

    2010-01-01

    We determined the feasibility and outcomes of the Log Handwriting Program (Raynal, 1990), an 8-week training program based on task-specific practice of handwriting. We used a pretest-posttest design involving 16 first- and second-grade Australian students. Handwriting training sessions occurred in schools for 45 min per week over 8 weeks, in groups of 2 or 3. Weekly homework was provided. The primary outcome measure was the Minnesota Handwriting Assessment (range = 0 to 34; Reisman, 1999). Legibility, form, alignment, size, spacing, and speed were measured. All six assessment subscales showed statistically significant differences. Legibility improved by a mean of 4.1 points (95% confidence interval = 2.5 to 5.7); form, 5.3 points; alignment, 7.8 points; size, 7.9 points; and space, 5.3 points. Speed decreased by 3.9 points. Preliminary evidence indicates that an 8-week Log Handwriting Program is feasible and improved handwriting in primary school children.

  3. Clay and Anxiety Reduction: A One-Group, Pretest/Posttest Design with Patients on a Psychiatric Unit

    ERIC Educational Resources Information Center

    Kimport, Elizabeth R.; Hartzell, Elizabeth

    2015-01-01

    Little research exists on using clay as an anxiety-reducing intervention with patients in psychiatric hospitals. This article reports on a study that used a one-group, pretest/posttest design with 49 adults in a psychiatric facility who created a clay pinch pot. The State-Trait Anxiety Inventory (STAI) was used as a pre- and posttest measure.…

  4. Pretest-Posttest-Posttest Multilevel IRT Modeling of Competence Growth of Students in Higher Education in Germany

    ERIC Educational Resources Information Center

    Schmidt, Susanne; Zlatkin-Troitschanskaia, Olga; Fox, Jean-Paul

    2016-01-01

    Longitudinal research in higher education faces several challenges. Appropriate methods of analyzing competence growth of students are needed to deal with those challenges and thereby obtain valid results. In this article, a pretest-posttest-posttest multivariate multilevel IRT model for repeated measures is introduced which is designed to address…

  5. Community health worker interventions are key to optimal infant immunization coverage, evidence from a pretest-posttest experiment in Mwingi, Kenya

    PubMed Central

    Nzioki, Japheth Mativo; Ouma, James; Ombaka, James Hebert; Onyango, Rosebella Ongutu

    2017-01-01

    Introduction Immunization is a powerful and cost-effective health intervention which averts an estimated 2 to 3 million deaths every year. Kenya has a high infant and under five mortality and morbidity rates. Increasing routine child immunization coverage is one way of reducing child morbidity and mortality rates in Kenya. Community Health Workers (CHWs) have emerged as critical human resources for health in developing countries. The Community Strategy (CS) is one of the CHW led interventions promoting Maternal and Child Health (MCH) in Kenya. This study sought to establish the effect of CS on infant vaccination Coverage (IVC) in Mwingi west sub-county; Kenya. Methods This was a pretest - posttest experimental study design with 1 pretest and 2 post-test surveys conducted in intervention and control sites. Mwingi west and Mwingi north sub-counties where intervention and control sites respectively. Sample size in each survey was 422 households. Women with a child aged 9-12 months were main respondents. Results Intervention site end-term evaluation indicated that; the CS increased IVC by 10.1% (Z =6.0241, P <0.0001), from a suboptimal level of 88.7% at baseline survey to optimal level of 98.8% at end term survey. Infants in intervention site were 2.5 times more likely to receive all recommended immunizations within their first year of life [(crude OR= 2.475, P<0.0001; 95%CI: 1.794-3.414) (adj. OR=2.516, P<0.0001; 95%CI: 1.796-3.5240)]. Conclusion CS increased IVC in intervention site to optimal level (98.8%). To improve child health outcomes through immunization coverage, Kenya needs to fast-track nationwide implementation of the CS intervention. PMID:29138657

  6. Community health worker interventions are key to optimal infant immunization coverage, evidence from a pretest-posttest experiment in Mwingi, Kenya.

    PubMed

    Nzioki, Japheth Mativo; Ouma, James; Ombaka, James Hebert; Onyango, Rosebella Ongutu

    2017-01-01

    Immunization is a powerful and cost-effective health intervention which averts an estimated 2 to 3 million deaths every year. Kenya has a high infant and under five mortality and morbidity rates. Increasing routine child immunization coverage is one way of reducing child morbidity and mortality rates in Kenya. Community Health Workers (CHWs) have emerged as critical human resources for health in developing countries. The Community Strategy (CS) is one of the CHW led interventions promoting Maternal and Child Health (MCH) in Kenya. This study sought to establish the effect of CS on infant vaccination Coverage (IVC) in Mwingi west sub-county; Kenya. This was a pretest - posttest experimental study design with 1 pretest and 2 post-test surveys conducted in intervention and control sites. Mwingi west and Mwingi north sub-counties where intervention and control sites respectively. Sample size in each survey was 422 households. Women with a child aged 9-12 months were main respondents. Intervention site end-term evaluation indicated that; the CS increased IVC by 10.1% (Z =6.0241, P <0.0001), from a suboptimal level of 88.7% at baseline survey to optimal level of 98.8% at end term survey. Infants in intervention site were 2.5 times more likely to receive all recommended immunizations within their first year of life [(crude OR= 2.475, P<0.0001; 95%CI: 1.794-3.414) (adj. OR=2.516, P<0.0001; 95%CI: 1.796-3.5240)]. CS increased IVC in intervention site to optimal level (98.8%). To improve child health outcomes through immunization coverage, Kenya needs to fast-track nationwide implementation of the CS intervention.

  7. Y-Balance Test Performance Following a Competitive Field Hockey Season: A Pretest-Posttest Study.

    PubMed

    Hoch, Matthew C; Welsch, Lauren A; Hartley, Emily M; Powden, Cameron J; Hoch, Johanna M

    2017-05-22

    The Y-Balance Test (YBT) is a dynamic balance assessment used as a preseason musculoskeletal screen to determine injury risk. While the YBT has demonstrated excellent test-retest reliability, it is unknown if YBT performance changes following participation in a competitive athletic season. Determine if a competitive athletic season affects YBT performance in field hockey players. Pretest-posttest. Laboratory. Twenty NCAA Division I women's field hockey players (age=19.55±1.30 years; height=165.10±5.277cm; mass=62.62±4.64kg) from a single team volunteered. Participants had to be free from injury throughout the entire study and participate in all athletic activities. Participants completed data collection sessions prior to (preseason) and following the athletic season (postseason). Between data collections, participants competed in the fall competitive field hockey season, which was ~3 months in duration. During data collection, participants completed the YBT bilaterally. The independent variable was time (preseason, postseason) and the dependent variables were normalized reach distances (anterior, posteromedial, posterolateral, composite) and between-limb symmetry for each reach direction. Differences between preseason and postseason were examined using paired t-tests (p≤0.05) as well as Bland-Altman limits of agreement. Four players sustained a lower extremity injury during the season and were excluded from analysis. There were no significant differences between preseason and postseason reach distances for any reach directions on either limb (p≥0.31) or in the between-limb symmetries (p≥0.52). The limits of agreement analyses determined there was a low mean bias across measurements (≤1.67%); however, the 95% confidence intervals indicated there was high variability within the posterior reach directions over time (±4.75-±14.83%). No changes in YBT performance were identified following a competitive field hockey season in Division I female athletes

  8. Student nurses' de-escalation of patient aggression: a pretest-posttest intervention study.

    PubMed

    Nau, Johannes; Halfens, Ruud; Needham, Ian; Dassen, Theo

    2010-06-01

    Experts recommend staff training to prevent and manage aggressive situations involving patients or their relatives. However, in many countries this subject is not covered in pre-registration nursing education. In addition, the evidence regarding its impact on practical placements remains weak. This study examines the influence of an aggression management training programme for nursing students on their performance in de-escalating aggressive patients. Pretest-posttest within-and-between-groups design. A School of Nursing in Germany. Convenience sample out of six classes of nursing students at differing educational levels (10th to 28th month of nursing education, n=78, mean age=22). In a cross-sectional and longitudinal two groups before and after design nursing students encountered two scenarios (A or B) with simulation patients. After completing the training, each student was confronted with the unknown other scenario. De-escalation experts from three German-speaking countries evaluated 156 video scenes using the De-escalating Aggressive Behaviour Scale (DABS), not knowing whether the videos had been recorded before or after the training. Mean values and statistical significance tests were computed to compare the results. The performance levels of students who had been trained rose significantly from 2.74 to 3.65 as measured by the DABS on a 5-point Likert scale (Wilcoxon test p<.001). The trained students managed scenario A significantly better than the untrained students (untrained 2.50, trained 3.70; Mann-Whitney-U-test p<.001,). Similar results were found for scenario B (untrained 3.01, trained 3.61; Mann-Whitney-U-test p<.001). No significant differences were found in the pretest results irrespective the students' age or duration of previous nursing education. Aggression management training is able to improve nursing students' performance in de-escalating aggressive behaviour. A maturation-effect on the de-escalating performance due to general nursing

  9. Ambroxol for fibromyalgia: one group pretest-posttest open-label pilot study.

    PubMed

    Martínez-Martínez, Laura-Aline; Pérez, Luis-Fernando; Becerril-Mendoza, Lizbeth-Teresa; Rodríguez-Henriquez, Pedro; Muñoz, Omar-Eloy; Acosta, Gumaro; Silveira, Luis H; Vargas, Angélica; Barrera-Villalpando, María-Isabel; Martínez-Lavín, Manuel

    2017-08-01

    A consistent line of investigation proposes that fibromyalgia is a sympathetically maintained neuropathic pain syndrome. Dorsal root ganglia sodium channels may play a major role in fibromyalgia pain transmission. Ambroxol is a secretolytic agent used in the treatment of various airway disorders. Recently, it was discovered that this compound is also an efficient sodium channel blocker with potent anti-neuropathic pain properties. We evaluated the add-on effect of ambroxol to the treatment of fibromyalgia. We studied 25 patients with fibromyalgia. Ambroxol was prescribed at the usual clinical dose of 30 mg PO 3 times a day × 1 month. At the beginning and at the end of the study, all participants filled out the Revised Fibromyalgia Impact Questionnaire (FIQ-R) and the 2010 ACR diagnostic criteria including the widespread pain index (WPI). At the end of the study, FIQ-R decreased from a baseline value of 62 ± 15 to 51 ± 19 (p = 0.013). Pain visual analogue scale decreased from 77 ± 14 to 56 ± 30 (p = 0.018). WPI diminished from 14.6 ± 3.1 to 10.4 ± 5.3 (p = 0.001). Side effects were minor. In this pilot study, the use of ambroxol was associated to decreased fibromyalgia pain and improved fibromyalgia symptoms. The open nature of our study does not allow extracting the placebo effect from the positive results. The drug was well tolerated. Ambroxol newly recognized pharmacological properties could theoretically interfere with fibromyalgia pain pathways. Dose escalating-controlled studies seem warranted.

  10. Sensitivity, predictive values, pretest-posttest probabilities, and likelihood ratios of presurgery clinical diagnosis of nonmelanoma skin cancers.

    PubMed

    Ermertcan, Aylin Türel; Oztürk, Ferdi; Gençoğlan, Gülsüm; Eskiizmir, Görkem; Temiz, Peyker; Horasan, Gönül Dinç

    2011-03-01

    The precision of clinical diagnosis of skin tumors is not commonly measured and, therefore, very little is known about the diagnostic ability of clinicians. This study aimed to compare clinical and histopathologic diagnoses of nonmelanoma skin cancers with regard to sensitivity, predictive values, pretest-posttest probabilities, and likelihood ratios. Two hundred nineteen patients with 241 nonmelanoma skin cancers were enrolled in this study. Of these patients, 49.4% were female and 50.6% were male. The mean age ± standard deviation (SD) was 63.66 ± 16.44 years for the female patients and 64.77 ± 14.88 years for the male patients. The mean duration of the lesions was 20.90 ± 32.95 months. One hundred forty-eight (61.5%) of the lesions were diagnosed as basal cell carcinoma (BCC) and 93 (38.5%) were diagnosed as squamous cell carcinoma (SCC) histopathologically. Sensitivity, positive predictive value, and posttest probability were calculated as 75.96%, 87.77%, and 87.78% for BCC and 70.37%, 37.25%, and 37.20% for SCC, respectively. The correlation between clinical and histopathologic diagnoses was found to be higher in BCC. Knowledge of sensitivity, predictive values, likelihood ratios, and posttest probabilities may have implications for the management of skin cancers. To prevent unnecessary surgeries and achieve high diagnostic accuracies, multidisciplinary approaches are recommended.

  11. A single group, pretest-posttest clinical trial for the effects of dry needling on wrist flexors spasticity after stroke.

    PubMed

    Fakhari, Zahra; Ansari, Noureddin Nakhostin; Naghdi, Soofia; Mansouri, Korosh; Radinmehr, Hojjat

    2017-01-01

    Spasticity is a common complication after stroke. Dry needling (DN) is suggested as a novel method for treatment of muscle spasticity. To explore the effects of DN on wrist flexors spasticity poststroke. A single group, pretest-posttest clinical trial was used. Twenty nine patients with stroke (16 male; mean age 54.3 years) were tested at baseline (T0), immediately after DN (T1), and one hour after DN (T2). DN was applied for flexor carpi radialis (FCR) and flexor carpi ulnaris on the affected arm for single session, one minute per muscle. The Modified Modified Ashworth Scale (MMAS), passive resistance force, wrist active and passive range of motion, Box and Block Test, and FCR H-reflex were outcome measures. Significant reductions in MMAS scores were seen both immediately after DN and at 1-hour follow-up (median 2 at T0 to 1 at T1 and T2). There were significant improvements in other measures between the baseline values at T0 and those recorded immediately after the DN at T1 or one hour later at T2. This study suggests that DN reduced wrist flexors spasticity and alpha motor neuron excitability in patients with stroke, and improvements persisted for one hour after DN.

  12. Examining Students' Self-Perceived Competence and Comfort in an Experiential Play Therapy Counseling Course: A Single Group Pretest-Posttest Investigation

    ERIC Educational Resources Information Center

    Flasch, Paulina; Taylor, Dalena; Clauber, Rikke Nynne; Robinson, Edward, III

    2017-01-01

    The current study utilized a single-group pretest-posttest design to evaluate students' self-perceived competence and comfort of using a variety of play therapy techniques and interventions with a range of client populations as a result of taking a one-week intensive course in Play Therapy. In an effort to conduct course evaluation and explore…

  13. Patient satisfaction is biased by renovations to the interior of a primary care office: a pretest-posttest assessment.

    PubMed

    Tièche, Raphaël; da Costa, Bruno R; Streit, Sven

    2016-08-11

    Measuring quality of care is essential to improve primary care. Quality of primary care for patients is usually assessed by patient satisfaction questionnaires. However, patients may not be able to judge quality of care without also reflecting their perception of the environment. We determined the effect that redesigning a primary care office had on patient satisfaction. We hypothesized that renovating the interior would make patients more satisfied with the quality of medical care. We performed a Pretest-Posttest analysis in a recently renovated single-practice primary care office in Grenchen, Switzerland. Before and after renovation, we distributed a questionnaire to assess patient satisfaction in four domains. We chose a Likert scale (1 = very poor to 6 = very good), and 12 quality indicators, and included two consecutive samples of patients presenting at the primary care office before (n = 153) and after (n = 153) interior design renovation. Response rate was high (overall 85 %). The sample was similar to the enlisted patient collective, but the sample population was older (60 years) than the collective (52 years). Patient satisfaction was higher for all domains after the office was renovated (p < 0.01-0.001). Results did not change when we included potential confounders in the multivariable model (p < 0.01). Renovating the interior of a primary care office was associated with improved patient satisfaction, including satisfaction in domains otherwise unchanged. Physician skills and patient satisfaction sometimes depend on surrounding factors that may bias the ability of patients to assess the quality of medical care. These biases should be taken into account when quality assessment instruments are designed for patients.

  14. Effects of a job crafting intervention program on work engagement among Japanese employees: a pretest-posttest study.

    PubMed

    Sakuraya, Asuka; Shimazu, Akihito; Imamura, Kotaro; Namba, Katsuyuki; Kawakami, Norito

    2016-10-24

    Job crafting, an employee-initiated job design/redesign, has become important for employees' well-being such as work engagement. This study examined the effectiveness of a newly developed job crafting intervention program on work engagement (as primary outcome), as well as job crafting and psychological distress (as secondary outcomes), using a pretest-posttest study design among Japanese employees. Participants were managers of a private company and a private psychiatric hospital in Japan. The job crafting intervention program consisted of two 120-min sessions with a two-week interval between them. Outcomes were assessed at baseline (Time 1), post-intervention (Time 2), and a one-month follow-up (Time 3). The mixed growth model analyses were conducted using time (Time 1, Time 2, and Time 3) as an indicator of intervention effect. Effect sizes were calculated using Cohen's d. The program showed a significant positive effect on work engagement (t = 2.20, p = 0.03) in the mixed growth model analyses, but with only small effect sizes (Cohen's d = 0.33 at Time 2 and 0.26 at Time 3). The program also significantly improved job crafting (t = 2.36, p = 0.02: Cohen's d = 0.36 at Time 2 and 0.47 at Time 3) and reduced psychological distress (t = -2.06, p = 0.04: Cohen's d = -0.15 at Time 2 and -0.31 at Time 3). The study indicated that the newly developed job crafting intervention program was effective in increasing work engagement, as well as in improving job crafting and decreasing psychological distress, among Japanese managers. UMIN Clinical Trials Registry UMIN000024062 . Retrospectively registered 15 September 2016.

  15. Balance exercise program reduced falls in people with multiple sclerosis: a single-group, pretest-posttest trial.

    PubMed

    Nilsagård, Ylva Elisabet; von Koch, Lena Kristina; Nilsson, Malin; Forsberg, Anette Susanne

    2014-12-01

    To evaluate the effects of a balance exercise program on falls in people with mild to moderate multiple sclerosis (MS). Multicenter, single-blinded, single-group, pretest-posttest trial. Seven rehabilitation units within 5 county councils. Community-dwelling adults with MS (N=32) able to walk 100m but unable to maintain 30-second tandem stance with arms alongside the body. Seven weeks of twice-weekly, physiotherapist-led 60-minute sessions of group-based balance exercise targeting core stability, dual tasking, and sensory strategies (CoDuSe). Primary outcomes: number of prospectively reported falls and proportion of participants classified as fallers during 7 preintervention weeks, intervention period, and 7 postintervention weeks. Secondary outcomes: balance performance on the Berg Balance Scale, Four Square Step Test, sit-to-stand test, timed Up and Go test (alone and with cognitive component), and Functional Gait Assessment Scale; perceived limitations in walking on the 12-item MS Walking Scale; and balance confidence on the Activities-specific Balance Confidence Scale rated 7 weeks before intervention, directly after intervention, and 7 weeks later. Number of falls (166 to 43; P≤.001) and proportion of fallers (17/32 to 10/32; P≤.039) decreased significantly between the preintervention and postintervention periods. Balance performance improved significantly. No significant differences were detected for perceived limitations in walking, balance confidence, the timed Up and Go test, or sit-to-stand test. The CoDuSe program reduced falls and proportion of fallers and improved balance performance in people with mild to moderate MS but did not significantly alter perceived limitations in walking and balance confidence. Copyright © 2014 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  16. Improving work functioning and mental health of health care employees using an e-mental health approach to workers' health surveillance: pretest-posttest study.

    PubMed

    Ketelaar, Sarah M; Nieuwenhuijsen, Karen; Bolier, Linda; Smeets, Odile; Sluiter, Judith K

    2014-12-01

    Mental health complaints are quite common in health care employees and can have adverse effects on work functioning. The aim of this study was to evaluate an e-mental health (EMH) approach to workers' health surveillance (WHS) for nurses and allied health professionals. Using the waiting-list group of a previous randomized controlled trial with high dropout and low compliance to the intervention, we studied the pre- and posteffects of the EMH approach in a larger group of participants. We applied a pretest-posttest study design. The WHS consisted of online screening on impaired work functioning and mental health followed by online automatically generated personalized feedback, online tailored advice, and access to self-help EMH interventions. The effects on work functioning, stress, and work-related fatigue after 3 months were analyzed using paired t tests and effect sizes. One hundred and twenty-eight nurses and allied health professionals participated at pretest as well as posttest. Significant improvements were found on work functioning (p = 0.01) and work-related fatigue (p < 0.01). Work functioning had relevantly improved in 30% of participants. A small meaningful effect on stress was found (Cohen d = .23) in the participants who had logged onto an EMH intervention (20%, n = 26). The EMH approach to WHS improves the work functioning and mental health of nurses and allied health professionals. However, because we found small effects and participation in the offered EMH interventions was low, there is ample room for improvement.

  17. Power in randomized group comparisons: the value of adding a single intermediate time point to a traditional pretest-posttest design.

    PubMed

    Venter, Anre; Maxwell, Scott E; Bolig, Erika

    2002-06-01

    Adding a pretest as a covariate to a randomized posttest-only design increases statistical power, as does the addition of intermediate time points to a randomized pretest-posttest design. Although typically 5 waves of data are required in this instance to produce meaningful gains in power, a 3-wave intensive design allows the evaluation of the straight-line growth model and may reduce the effect of missing data. The authors identify the statistically most powerful method of data analysis in the 3-wave intensive design. If straight-line growth is assumed, the pretest-posttest slope must assume fairly extreme values for the intermediate time point to increase power beyond the standard analysis of covariance on the posttest with the pretest as covariate, ignoring the intermediate time point.

  18. Quasi-experimental evaluation without regression analysis.

    PubMed

    Rohrer, James E

    2009-01-01

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

  19. Tailoring communication in cancer genetic counseling through individual video-supported feedback: a controlled pretest-posttest design.

    PubMed

    Pieterse, Arwen H; van Dulmen, Alexandra M; Beemer, Frits A; Ausems, Margreet G E M; Bensing, Jozien M

    2006-03-01

    To assess the influence of a 1-day individual video-feedback training for cancer genetic counselors on the interaction during initial visits. Feedback was intended to help counselors make counselees' needs more explicit and increase counselors' sensitivity to these. In total 158 counselees, mainly referred for breast or colon cancer and visiting 1 of 10 counselors, received a pre- and post-visit questionnaire assessing needs (fulfillment). Visits were videotaped, counselor eye gaze was assessed, and verbal communication was analyzed by Roter Interaction Analysis System (RIAS) adapted to the genetic setting. Halfway the study, five counselors were trained. Trained counselors provided more psychosocial information, and with trained counselors emotional consequences of DNA-testing was more often discussed. Counselees seen by a trained counselor considered their need for explanations on (emotional) consequences of counseling as better fulfilled. Unexpectedly, counselees' contribution to the interaction was smaller with trained counselors. Feedback appeared to result in greater emphasis on psychosocial issues, without lengthening the visit. However, counselors did not become more verbally supportive in other ways than by providing information. A 1 day individual training appears effective to some extend; increased opportunities for watching and practicing behavioral alternatives and arranging consolidating sessions may improve training results.

  20. Impact of a contextual intervention on child participation and parent competence among children with autism spectrum disorders: a pretest-posttest repeated-measures design.

    PubMed

    Dunn, Winnie; Cox, Jane; Foster, Lauren; Mische-Lawson, Lisa; Tanquary, Jennifer

    2012-01-01

    OBJECTIVE. We tested an occupational therapy contextual intervention for improving participation in children with autism spectrum disorders and for developing parental competence. METHOD. Using a repeated-measures pretest-posttest design, we evaluated the effectiveness of a contextually relevant reflective guidance occupational therapy intervention involving three components: authentic activity settings, family's daily routines, and the child's sensory processing patterns (Sensory Profile). We used these components to coach 20 parents in strategies to support their child's participation. Intervention sessions involved reflective discussion with parents to support them in identifying strategies to meet their goals and make joint plans for the coming week. We measured child participation (Canadian Occupational Performance Measure, Goal Attainment Scaling) and parent competence (Parenting Sense of Competence, Parenting Stress Index). RESULTS. Results indicated that parents felt more competent and children significantly increased participation in everyday life, suggesting that this approach is an effective occupational therapy intervention. Copyright © 2012 by the American Occupational Therapy Association, Inc.

  1. Curriculum evaluation and revision in a nascent field: the utility of the retrospective pretest--posttest model in a homeland security program of study.

    PubMed

    Pelfrey, William V; Pelfrey, William V

    2009-02-01

    Although most academic disciplines evolve at a measured pace, the emerging field of homeland security must, for reasons of safety and security, evolve rapidly. The Department of Homeland Security sponsored the establishment of a graduate educational program for key officials holding homeland security roles. Because homeland security is a nascent field, the establishment of a program curriculum was forced to draw from a variety of disciplines. Curriculum evaluation was complicated by the rapid changes occurring in the emerging discipline, producing response shift bias, and interfering with the pre-post assessments. To compensate for the validity threat associated with response shift bias, a retrospective pretest-posttest evaluative methodology was used. Data indicate the program has evolved in a significant and orderly fashion and these data support the use of this innovative evaluation approach in the development of any discipline.

  2. Applying evidence-based health care to musculoskeletal patients as an educational strategy for chiropractic interns (a one-group pretest-posttest study).

    PubMed

    Fernandez, Charles E; Delaney, Paul M

    2004-05-01

    To describe and measure the effectiveness of a problem-based educational strategy for teaching evidence-based health care (EBHC) to chiropractic interns, which focused on the development and appraisal of answerable clinical questions using actual musculoskeletal patients. A 1-group pretest-posttest design (simple panel design) with investigator-blinded survey administration was used to measure effectiveness of educational activities using adult learning theory with a study population of interns (n=31) at a chiropractic college (Los Angeles College of Chiropractic, Southern California University of Health Sciences [LACC/SCUHS]) teaching clinic. Activities included 2 workshops on constructing clinical questions and critical appraisal of published research and independent patient-based EBHC assignments. A qualitative self-assessment survey was administered before and after a 6-week period of EBHC activities to measure their effectiveness. Sign tests and paired t tests were utilized to determine P values for significant difference of score results. Eighty-one percent of subjects completed the pretest-posttest surveys. All survey item responses showed an average increase in subjects' self-rating of skills and attitudes from pretest to posttest. There were statistically significant differences in interns' self-assessed ability to construct an answerable clinical question and appraise research articles and apply them to patient management, as well as their rating of importance of EBHC in patient decision making. The results of this study suggest that having chiropractic interns apply EBHC to actual musculoskeletal patients along with attending EBHC workshops had a positive impact on interns' perceived ability to practice EBHC.

  3. Internal Invalidity in Pretest-Posttest Self-Report Evaluations and a Re-Evaluation of Retrospective Pretests.

    ERIC Educational Resources Information Center

    Howard, George S.; And Others

    1979-01-01

    True experimental designs are thought to provide internally valid results. In this investigation of the evaluations of five interventions, a source of internal invalidity is identified when self-report measures are used. An alternative approach is presented and implications of the findings for evaluation research are discussed. (JKS)

  4. Enhancing staff attitudes, knowledge and skills in supporting the self-determination of adults with intellectual disability in residential settings in Hong Kong: a pretest-posttest comparison group design.

    PubMed

    Wong, P K S; Wong, D F K

    2008-03-01

    The ecological perspective recognizes the critical role that is played by rehabilitation personnel in helping people with intellectual disability (ID) to exercise self-determination, particularly in residential settings. In Hong Kong, the authors developed the first staff training programme of its kind to strengthen the competence of personnel in this area. The purpose of this study was to examine the effectiveness of staff training in enhancing residential staff's attitudes, knowledge and facilitation skills in assisting residents with ID to exercise self-determination. A pretest-posttest comparison group design was adopted. Thirty-two participants in an experimental group attended a six-session staff training programme. A 34-item self-constructed scale was designed and used for measuring the effectiveness of the staff training. The results showed that the experimental group achieved statistically significant positive changes in all domains, whereas no significant changes were found in the comparison group. The findings provided initial evidence of the effectiveness of staff training that uses an interactional attitude-knowledge-skills model for Chinese rehabilitation personnel. The factors that contributed to its effectiveness were discussed and recommendations for future research were made.

  5. An Experimental Study of Interventions for the Acquisition and Retention of Motivational Interviewing Skills among Probation Officers

    ERIC Educational Resources Information Center

    Asteris, Mark M., Jr.

    2012-01-01

    This study was designed to investigate the differences in Motivational Interviewing (MI) skill acquisition and retention among probation officers. This study had a randomized, experimental, pretest-posttest control group design using the MITI 3.1.1 and the VASE-R to measure MI skill acquisition and retention. A random sample (n = 24) of probation…

  6. The Effect of Tonality and Rhythm on Memory Recall in Elementary General Education Classrooms: A Quasi-Experimental Study

    ERIC Educational Resources Information Center

    Varnell, Matt

    2013-01-01

    The purpose of this study was to evaluate the effect of rhythm and tonality on an academic memory task by comparing three different treatment conditions: a poem, a rhythmic chant (or rap), and a melodic rhythm (or song). A quasi-experimental experiment was designed and implemented, specifically a pretest-posttest-posttest control-group design.…

  7. Comprehension and Motivation Levels in Conjunction with the Use of eBooks with Audio: A Quasi-Experimental Study of Post-Secondary Remedial Reading Students

    ERIC Educational Resources Information Center

    Wheeler, Kimberly W.

    2014-01-01

    This quasi-experimental pretest, posttest nonequivalent control group study investigated the comprehension scores and motivation levels of post-secondary remedial reading students in a two-year technical college in Northwest Georgia using an eBook, an eBook with audio, and a print book. After reading a module on Purpose and Tone in the three book…

  8. A Quasi-Experimental Study on Using Short Stories: Statistical and Inferential Analyses on the Non-English Major University Students' Speaking and Writing Achievements

    ERIC Educational Resources Information Center

    Iman, Jaya Nur

    2017-01-01

    This research was conducted to find out whether or not using short stories significantly improve the speaking and writing achievements. A quasi-experimental study of non-equivalent pretest-posttest control group design or comparison group design was used in this research. The population of this research was the all first semester undergraduate…

  9. Effects of Emotional Intelligence and Locus of Control Training on the Psychological Well-Being of Adolescents with Visual Impairments in Nigeria

    ERIC Educational Resources Information Center

    Eniola, M. S.; Ajobiewe, Abthonia Ifeoma

    2013-01-01

    This current study, investigated the relative effectiveness of Emotional Intelligence Training (EIT) and Locus of Control Training (LCT) on the psychological well-being of adolescent with visual impairment. The pretest-posttest control group experimental design with a 3x2x2 factorial matrix was used. The participants were 120 adolescents with…

  10. Application of Experimental and Quasi-Experimental Research Designs to Educational Software Evaluation.

    ERIC Educational Resources Information Center

    Muller, Eugene W.

    1985-01-01

    Develops generalizations for empirical evaluation of software based upon suitability of several research designs--pretest posttest control group, single-group pretest posttest, nonequivalent control group, time series, and regression discontinuity--to type of software being evaluated, and on circumstances under which evaluation is conducted. (MBR)

  11. Increasing cardiopulmonary aerobic activity improves motor cognitive response time: An inference from preliminary one-group pretest-posttest quasi-experimental study.

    PubMed

    Mishra, Rajnee; Dasgupta, Aurodeep; Mohan, Vivek; Aranha, Vencita Priyanka; Samuel, Asir John

    Motor cognitive response time (MCRT) is the time elapsed between presenting a stimulus and the time taken by that individual to respond to that stimulus through a motor performance. After completing aerobic exercise, there are various changes that takes place, one of which might be change in cognitive function. Whether cardiopulmonary aerobic activity/capacity has an impact on MCRT is not explored yet. Copyright © 2017. Published by Elsevier B.V.

  12. Reflections on experimental research in medical education.

    PubMed

    Cook, David A; Beckman, Thomas J

    2010-08-01

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

  13. Effectiveness of Adherence Therapy for People With Schizophrenia in Turkey: A Controlled Study.

    PubMed

    Dikec, Gul; Kutlu, Yasemin

    2016-04-01

    This study used a quasi-experimental design with a pretest-posttest control group and follow-up to determine the efficacy of adherence therapy in patients with schizophrenia in Turkey. The sample of this study consisted of patients with schizophrenia (n=30). The Questionnaire Form, Medication Adherence Rating Scale, Internalized Stigma of Mental Illness Scale, and Beck Cognitive Insight Scale were used. The patients were assigned to experimental (n=15) and control (n=15) groups using the randomization method. The experimental group received adherence therapy in eight sessions. When the scores of the patients in the experimental and control groups were compared at the pretest, posttest, and 3- and 6-months follow ups, a significant difference was only found in the Medication Adherence Rating Scale posttest scores. Adherence therapy is effective in improving adherence to treatment but is not effective with regard to insight and internalized stigma in patients with schizophrenia. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. The Role of Occupational Therapy in Promoting Playfulness, Parent Competence, and Social Participation in Early Childhood Playgroups: A Pretest Posttest Design

    ERIC Educational Resources Information Center

    Fabrizi, Sarah; Hubbell, Kristin

    2017-01-01

    This study examined the effects of an inclusive, community-based playgroup intervention on parent and child outcomes. The role of occupational therapy as part of a team of providers in early childhood was also explored. Caregiver-child dyads (n = 36) were enrolled in one of three playgroup conditions (control, occupational therapy support, and…

  15. The user experiences and clinical outcomes of an online personal health record to support self-management of bipolar disorder: A pretest-posttest pilot study.

    PubMed

    van den Heuvel, Silvio C G H; Meije, Daniëlle; Regeer, Eline J; Sinnema, Henny; Riemersma, Rixt F; Kupka, Ralph W

    2018-06-03

    Self-management comprises knowledge, behavior, activities and resources providing people with bipolar disorder (BD) control over fluctuating mood and activity-patterns. The 'Self-management and Dialogue in Bipolar Disorder' project entailed the tailoring of an online personal health record (PHR) originally designed for the chronically ill to monitor condition and share information with their clinician to people with BD (PHR-BD). The aim of this study was to evaluate the feasibility, utility and user-experiences of participants with BD, relatives, and healthcare professionals who worked with the PHR-BD. Post-test online closed- and open ended questionnaires were used to collect information on utility, and user-experiences with PHR-BD. A pre-posttest design to evaluate clinical effects on quality of life, empowerment, symptom reduction, changes in mood and activity, and illness burden and severity at baseline and at 12-months follow-up. Sixty-six participants with BD logged in at baseline. At study endpoint thirty-nine participants with BD, eleven professionals and one family caregiver filled out the evaluations. No significant differences in the clinical outcomes from baseline were found. Qualitative evaluations showed a frequent utility of the mood chart modules, improved communication between clinician and participant with BD and, increased insight in influencing factors of mood fluctuations. Small convenience sample, no controls. The option to alternate the interface from a prospective to a retrospective mood chart , and integration with the personal crisis plan was considered to be of added value in self-managing BD. The findings of this study will guide the future implementation of the PHR-BD. Copyright © 2018 Elsevier B.V. All rights reserved.

  16. A single-group pretest posttest design using full kinetic chain manipulative therapy with rehabilitation in the treatment of 18 patients with hip osteoarthritis.

    PubMed

    Brantingham, James W; Globe, Gary A; Cassa, Tammy Kay; Globe, Denise; de Luca, Katie; Pollard, Henry; Lee, Felix; Bates, Charles; Jensen, Muffit; Mayer, Stephan; Korporaal, Charmaine

    2010-01-01

    Hip osteoarthritis (HOA) affects 30 million Americans or more, and is a leading cause of disability, suffering, and pain. Standard treatments are minimally effective and carry significant risk and expense. This study assessed treatment effects of a chiropractic protocol for HOA. Eighteen individuals, who did not qualify due to low baseline Western Ontario and McMaster Osteoarthritis Index scores (WOMAC) for other ongoing HOA randomized control trials, were selected. A prospectively planned protocol, consisting of axial manipulation to the affected hip with modified Thomas and active assisted stretch, was combined with full kinetic chain treatment or manipulative therapy to the spine, knee, ankle, or foot and assessed with use of valid and reliable outcome measures. The primary outcome measure, the Overall Therapy Effectiveness Tool, was assessed with chi(2) and demonstrated that 83.33% of participants were improved after the ninth visit, P = .005, and 78% improved at the 3-month follow-up, P = .018. Using the paired t test, WOMAC was improved 64% at the ninth visit, P = .000, and 47% at follow-up, P = .016. In HOA patients with lower WOMAC scores, a highly organized HOA treatment appears to have resulted in statistically and clinically meaningful intragroup changes in the Overall Effectiveness Therapy Tool, WOMAC, Harris Hip Scale, and range of motion, all with P

  17. Understanding interrelationships among HIV-related stigma, concern about HIV infection, and intent to disclose HIV serostatus: a pretest-posttest study in a rural area of eastern China.

    PubMed

    Liu, Hongjie; Hu, Zhi; Li, Xiaoming; Stanton, Bonita; Naar-King, Sylvie; Yang, Hongmei

    2006-02-01

    The objective of the study was to examine the interrelationships among HIV-related public and felt stigma, worry of HIV infection, HIV/AIDS knowledge and intention to disclose HIV testing results in a rural area of China, where HIV spread among former commercial blood donors. A one-group pretest-posttest study was conducted among 605 marriage license applicants. The following relationships showed statistical significance in path analysis: (1) HIV/AIDS knowledge --> worry [beta (Standardized coefficient) = -0.39]; (2) worry --> public stigma (beta = 0.27); (3) public stigma --> felt stigma (beta = 0.22); and (4) felt stigma --> intention to disclosure (beta = -0.20). Separate path analyses for males and females generated similar association patterns. HIV counseling reduced perceived worry but exerted little impact on HIV-related stigma and the intention. The pathway from a lack of HIV/AIDS knowledge to increased stigma and to decreased intention to disclose one's serostatus is particularly policy relevant as decreased intention to disclosure may be related to continuing practice of HIV risk behaviors. The findings demonstrate interventions aiming at the reduction of stigma should be targeted at both the individual and community levels.

  18. Effects of static stretching of knee musculature on patellar alignment and knee functional disability in male patients diagnosed with knee extension syndrome: A single-group, pretest-posttest trial.

    PubMed

    Pourahmadi, Mohammad Reza; Ebrahimi Takamjani, Ismail; Hesampour, Kazem; Shah-Hosseini, Gholam Reza; Jamshidi, Ali Ashraf; Shamsi, Mohammad Bagher

    2016-04-01

    Knee extension (Kext) syndrome is based on movement system impairments and is described as knee pain associated with quadriceps stiffness. To investigate the effects of 3 times per week for 4 weeks static stretching of knee musculature on patellar alignment and knee functional disability in male Kext syndrome patients. A single-group, pretest-posttest clinical trial. Hazrat-e-Rasoul Akram Hospital. Forty-six male Kext syndrome patients aged 18-35 years. Knee functional disability was assessed by the Kujala questionnaire. Patellar tilt was assessed using the skyline view X-ray. In addition, patella alta was assessed by X-ray using the Insall-Salvati ratio. After intervention, changes in knee flexion-extension range of motion (ROM) and hip adduction were assessed by goniometer and inclinometer. Changes in patellar tilt and patella alta were evaluated. Correlations between muscles length, patellar tilt and knee functional disability were also evaluated. The mean of patellar tilt in male Kext syndrome patients was 15.19°. Only the correlation between rectus femoris shortness and patellar tilt (P = 0.002) and the correlation between rectus femoris shortness and knee functional disability (P = 0.037) were significant. Patella alta was not severe in male Kext syndrome patients (1.28 ± 0.10). Knee flexion-extension ROM and femoral adduction increased significantly after a 12-session stretching programme (P < 0.0001). The results demonstrated that rectus femoris shortness had higher correlation with patellar tilt and knee functional disability than iliotibial band and hamstring shortness. Stretching was effective in reducing patellar tilt, patella alta, knee functional disability, increasing knee ROM and hip adduction in these patients. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Serum brain-derived neurotrophic factor levels in treatment-naïve boys with attention-deficit/hyperactivity disorder treated with methylphenidate: an 8-week, observational pretest-posttest study.

    PubMed

    Akay, Aynur Pekcanlar; Resmi, Halil; Güney, Sevay Alsen; Erkuran, Handan Özek; Özyurt, Gonca; Sargin, Enis; Topuzoglu, Ahmet; Tufan, Ali Evren

    2018-01-01

    Brain-derived neurotrophic factor (BDNF) is an important neurotrophin in the brain that modulates dopaminergic neurons. In this study, we aimed to investigate the changes in serum BDNF levels of children with attention-deficit/hyperactivity disorder (ADHD) in response to OROS methylphenidate treatment. We also aimed to determine whether there were any pre-post-differences between ADHD subtypes and comorbid psychiatric disorders in serum BDNF levels. Fifty male children with ADHD and 50 male healthy controls within the age range of 6-12 years were recruited to the study. The psychiatric diagnoses were determined by applying a structured interview with Kiddie schedule for affective disorders and schizophrenia for school-age children-present and lifetime version. The symptom severity of ADHD was measured using the Clinical Global Impression ADHD Severity Scale (CGI-S). Physicians completed Du Paul ADHD questionnaires. The levels of serum BDNF were assessed before and after 8 weeks of treatment with effective dosages of OROS methylphenidate. In the present study, the mean serum BDNF levels of boys with ADHD and of the healthy controls were 2626.33 ± 1528.05 and 2989.11 ± 1420.08 pg/mL, respectively. Although there were no statistically significant difference between the ADHD group and healthy controls at baseline (p = 0.22), the increase of serum BDNF was statistically significant from baseline to endpoint in the ADHD group (p = 0.04). The mean serum BDNF levels at baseline and endpoint of the ADHD group were 2626.33 ± 1528.05 and 3255.80 ± 1908.79 pg/mL, respectively. The serum BDNF levels of ADHD-inattentive subtype were significantly lower at baseline (p = 0.02), whereas BDNF levels post-treatment showed no significant difference. The increase of serum BDNF levels with methylphenidate treatment after 8 weeks was significantly higher in the inattentive group (p = 0.005). The increase of serum BDNF levels with methylphenidate treatment after 8

  20. Pretest/Posttest Plus Prompts: Tools for Research and Evaluation

    ERIC Educational Resources Information Center

    Herron, Sherry; Gopal, Tamilselvi

    2012-01-01

    We conducted a series of summer workshops on bioinformatics to increase educators' knowledge of this new field of inquiry with the assumption that their knowledge will, in turn, impact student achievement. The workshops incorporated experiential learning and self-reflection (Loucks-Horsley et al. 1998). Educators demonstrated significant increases…

  1. The effect of the support program on the resilience of female family caregivers of stroke patients: Randomized controlled trial.

    PubMed

    İnci, Fadime Hatice; Temel, Ayla Bayik

    2016-11-01

    The purpose of the study was to determine the effect of a support program on the resilience of female family caregivers of stroke patients. This is a randomized controlled trial. The sample consisted 70 female family caregivers (34 experimental, 36 control group). Data were collected three times (pretest-posttest, follow-up test). Data were collected using the demographical data form, the Family Index of Regenerativity and Adaptation-General. A significant difference was determined between the experimental and control group's follow-up test scores for relative and friend support, social support and family-coping coherence. A significant difference was determined between the experimental group's mean pretest, posttest and follow-up test scores in terms of family strain, relative and friend support, social support, family coping-coherence, family hardiness and family distress. These results suggest that the Support Program contributes to the improvement of the components of resilience of family caregivers of stroke patients. Copyright © 2016 Elsevier Inc. All rights reserved.

  2. Factors in Human-Computer Interface Design (A Pilot Study).

    DTIC Science & Technology

    1994-12-01

    This study used a pretest - posttest control group experimental design to test the effect of consistency on speed, retention, and user satisfaction. Four...analysis. The overall methodology was a pretest - posttest control group experimental design using different prototypes to test the effects of...methodology used for this study was a pretest - posttest control group experimental design using different prototypes to test for features of the human

  3. Quasi-experimental evaluation of a substance use awareness educational intervention for nursing students.

    PubMed

    Cadiz, David M; O'Neill, Chris; Butell, Sue S; Epeneter, Beverly J; Basin, Basilia

    2012-07-01

    This article reports on a study that evaluated the effectiveness of an educational intervention, Addressing Nurse Impairment, for addressing nursing students' knowledge acquisition, changes in self-efficacy to intervene, and changes in substance abuse stigma. A gap exists in nursing students' education regarding the risks of addiction within the profession and how to handle a colleague suspected of having a substance use disorder. The seminar was adapted from an existing evidence-based prevention program called Team Awareness, as well as information from focus groups and a pilot test. A quasi-experimental pretest-posttest design was used to evaluate the effect of the seminar. When the control and experimental groups were compared, the results indicated that the seminar significantly affected knowledge and self-efficacy to intervene but did not significantly affect stigma. This research contributes to the body of evidence related to educational interventions for nursing students regarding substance abuse in the nursing profession. Copyright 2012, SLACK Incorporated.

  4. The effects of cognitive-behavioral therapy on depression, anger, and self-control for Korean soldiers.

    PubMed

    Hyun, Myung-Sun; Chung, Hyang-In C; De Gagne, Jennie C; Kang, Hee Sun

    2014-02-01

    This quasi-experimental study examined the effects of cognitive-behavioral therapy (CBT) to control depression, anger, and self-control in soldiers from South Korea. Using a pretest-posttest design, the sample was composed of an experimental group (n = 16) and a control group (n = 12). The experimental group participated in four sessions of CBT. No significant differences were found between the groups with regard to demographic characteristics. Changes in the variables after the intervention were analyzed using Wilcoxon's signed-rank sum test. The depression scores decreased significantly after the intervention (z = -3.05, p = 0.002); whereas, the scores of state-trait anger and self-control did not change. In the control group, none of the outcome variable scores changed significantly. The results indicate that the developed CBT program might be an effective modality to decrease the depression of soldiers who are in military service. Copyright 2014, SLACK Incorporated.

  5. A Quasi-Experimental Study of Religiosity of Undergraduate Students Enrolled in an Online Christian Worldview Course

    ERIC Educational Resources Information Center

    Markette, Jo Ann Alicia Foley

    2012-01-01

    The purpose of this study was to examine whether or not a change in religiosity would occur in undergraduate students at a West Coast Christian university as a result of their participation in an online Christian worldview course. Twenty-six undergraduate students participated in this pretest posttest quasi-experimental study which employed the…

  6. Evaluating the Gifted Students' Understanding Related to Plasma State Using Plasma Experimental System and Two-Tier Diagnostic Test

    ERIC Educational Resources Information Center

    Korkmaz, Saadet Deniz; Ayas, Bahadir; Aybek, Eren Can; Pat, Suat

    2018-01-01

    The purpose of this study was to investigate the effectiveness of the experimental system design related to plasma state on the gifted students' understanding on the subject of the plasma state. To test the research hypothesis, one group pretest-posttest research model was carried out with 18 eighth-grade (4 girls and 14 boys) gifted students in…

  7. Evaluation of the Efficiency of the Nursing Care Plan Applied Using NANDA, NOC, and NIC Linkages to Elderly Women with Incontinence Living in a Nursing Home: A Randomized Controlled Study.

    PubMed

    Gencbas, Dercan; Bebis, Hatice; Cicek, Hatice

    2017-05-30

    Evaluate the efficiency of the nursing care plan, applied with the use of NANDA-I, NOC, and NIC (NNN) linkages, for elderly women with incontinence who live in nursing homes. A randomized controlled experimental design was applied. NNN linkages were prepared and applied for 12 weeks in an experimental group. NOC scales were evaluated again for two groups. A 0.5 NOC point change targeted in all elderly in the experimental group were provided between pretest-posttest scores. The experimental group had higher life quality and lower incontinence severity/symptoms than the control group. It is important that NNN linkages effective for solving the problems are used in different groups and with larger samples to create further evidence linking NNN. © 2017 NANDA International, Inc.

  8. Effectiveness of a handwriting readiness program in head start: a two-group controlled trial.

    PubMed

    Lust, Carol A; Donica, Denise K

    2011-01-01

    This study measured skill improvement in prewriting skills, kindergarten readiness, first-name writing, and handwriting-nonspecific fine motor skills of students at Head Start who participated in Handwriting Without Tears-Get Set for School (HWT-GSS) programming. We conducted a two-group, nonrandomized controlled trial using a pretest-posttest design at a rural Head Start. The effectiveness of adding the HWT-GSS curriculum in one preschool classroom was compared with a control classroom. On posttesting, the experimental group made significant improvements compared with the control group in prewriting, kindergarten readiness, and fine motor skills. Both groups made significant improvements between pretesting and posttesting in prewriting, first name writing, and school readiness. Adding HWT-GSS to the Head Start program would be beneficial in improving handwriting readiness skills.

  9. Analyzing Randomized Controlled Interventions: Three Notes for Applied Linguists

    ERIC Educational Resources Information Center

    Vanhove, Jan

    2015-01-01

    I discuss three common practices that obfuscate or invalidate the statistical analysis of randomized controlled interventions in applied linguistics. These are (a) checking whether randomization produced groups that are balanced on a number of possibly relevant covariates, (b) using repeated measures ANOVA to analyze pretest-posttest designs, and…

  10. Effectiveness of foot and hand massage in postcesarean pain control in a group of Turkish pregnant women.

    PubMed

    Degirmen, Nuriye; Ozerdogan, Nebahat; Sayiner, Deniz; Kosgeroglu, Nedime; Ayranci, Unal

    2010-08-01

    The aim of this study was to determine the efficiency of foot and hand massage on reducing postoperative pain in patients who had cesarean operation. This pretest-posttest design study was planned as a randomized controlled experimental study. In the light of the results, it was reported that the reduction in pain intensity was significantly meaningful in both intervention groups when compared to the control group. It was also noted that vital findings were measured comparatively higher before the massage in the test groups, and they were found to be relatively lower in the measurements conducted right before and after the massage, which was considered to be statistically meaningful. Foot and hand massage proved useful as an effective nursing intervention in controlling postoperative pain. 2010 Elsevier Inc. All rights reserved.

  11. Effects of Flipped Instruction on the Performance and Attitude of High School Students in Mathematics

    ERIC Educational Resources Information Center

    Casem, Remalyn Q.

    2016-01-01

    This study aimed to determine the effects of flipped instruction on the performance and attitude of high school students in Mathematics. The study made use of the true experimental design, specifically the pretest-posttest control group design. There were two instruments used to gather data, the pretest-posttest which was subjected to validity and…

  12. Comparing student clinical self-efficacy and team process outcomes for a DEU, blended, and traditional clinical setting: A quasi-experimental research study.

    PubMed

    Plemmons, Christina; Clark, Michele; Feng, Du

    2018-03-01

    Clinical education is vital to both the development of clinical self-efficacy and the integration of future nurses into health care teams. The dedicated education unit clinical teaching model is an innovative clinical partnership, which promotes skill development, professional growth, clinical self-efficacy, and integration as a team member. Blended clinical teaching models are combining features of the dedicated education unit and traditional clinical model. The aims of this study are to explore how each of three clinical teaching models (dedicated education unit, blended, traditional) affects clinical self-efficacy and attitude toward team process, and to compare the dedicated education unit model and blended model to traditional clinical. A nonequivalent control-group quasi-experimental design was utilized. The convenience sample of 272 entry-level baccalaureate nursing students included 84 students participating in a dedicated education unit model treatment group, 66 students participating in a blended model treatment group, and 122 students participating in a traditional model control group. Perceived clinical self-efficacy was evaluated by the pretest/posttest scores obtained on the General Self-Efficacy scale. Attitude toward team process was evaluated by the pretest/posttest scores obtained on the TeamSTEPPS® Teamwork Attitude Questionnaire. All three clinical teaching models resulted in significant increases in both clinical self-efficacy (p=0.04) and attitude toward team process (p=0.003). Students participating in the dedicated education unit model (p=0.016) and students participating in the blended model (p<0.001) had significantly larger increases in clinical self-efficacy compared to students participating in the traditional model. These findings support the use of dedicated education unit and blended clinical partnerships as effective alternatives to the traditional model to promote both clinical self-efficacy and team process among entry

  13. Instructional Climates in Preschool Children Who Are At-Risk. Part I: Object-Control Skill Development

    ERIC Educational Resources Information Center

    Robinson, Leah E.; Goodway, Jacqueline D.

    2009-01-01

    Part I of this study examined the effect of two 9-week instructional climates (low autonomy [LA] and mastery motivational climate [MMC]) on object-control (OC) skill development in preschoolers (N = 117). Participants were randomly assigned to an LA, MMC, or comparison group. OC skills were assessed at pretest, posttest, and retention test with…

  14. Learning Historical Thinking with Oral History Interviews: A Cluster Randomized Controlled Intervention Study of Oral History Interviews in History Lessons

    ERIC Educational Resources Information Center

    Bertram, Christiane; Wagner, Wolfgang; Trautwein, Ulrich

    2017-01-01

    The present study examined the effectiveness of the oral history approach with respect to students' historical competence. A total of 35 ninth-grade classes (N = 900) in Germany were randomly assigned to one of four conditions--live, video, text, or a (nontreated) control group--in a pretest, posttest, and follow-up design. Comparing the three…

  15. Promoting Experimental Problem-solving Ability in Sixth-grade Students Through Problem-oriented Teaching of Ecology: Findings of an intervention study in a complex domain

    NASA Astrophysics Data System (ADS)

    Roesch, Frank; Nerb, Josef; Riess, Werner

    2015-03-01

    Our study investigated whether problem-oriented designed ecology lessons with phases of direct instruction and of open experimentation foster the development of cross-domain and domain-specific components of experimental problem-solving ability better than conventional lessons in science. We used a paper-and-pencil test to assess students' abilities in a quasi-experimental intervention study utilizing a pretest/posttest control-group design (N = 340; average performing sixth-grade students). The treatment group received lessons on forest ecosystems consistent with the principle of education for sustainable development. This learning environment was expected to help students enhance their ecological knowledge and their theoretical and methodological experimental competencies. Two control groups received either the teachers' usual lessons on forest ecosystems or non-specific lessons on other science topics. We found that the treatment promoted specific components of experimental problem-solving ability (generating epistemic questions, planning two-factorial experiments, and identifying correct experimental controls). However, the observed effects were small, and awareness for aspects of higher ecological experimental validity was not promoted by the treatment.

  16. Within-Subject Comparison of Changes in a Pretest-Posttest Design

    ERIC Educational Resources Information Center

    Hennig, Christian; Mullensiefen, Daniel; Bargmann, Jens

    2010-01-01

    The authors propose a method to compare the influence of a treatment on different properties within subjects. The properties are measured by several Likert-type-scaled items. The results show that many existing approaches, such as repeated measurement analysis of variance on sum and mean scores, a linear partial credit model, and a graded response…

  17. A Retrospective Pretest-Posttest Evaluation of a One-Time Personal Finance Training

    ERIC Educational Resources Information Center

    Nielsen, Robert B.

    2011-01-01

    Attempts to measure the impact of Extension programs have been implemented to varying effects for many years. Using data from several economics of personal finance workshops designed to teach high school teachers about a state's new personal finance performance standards, this article reports the results from of one type of evaluation, a…

  18. Variability in Pretest-Posttest Correlation Coefficients by Student Achievement Level. NCEE 2011-4033

    ERIC Educational Resources Information Center

    Cole, Russell; Haimson, Joshua; Perez-Johnson, Irma; May, Henry

    2011-01-01

    State assessments are increasingly used as outcome measures for education evaluations. The scaling of state assessments produces variability in measurement error, with the conditional standard error of measurement increasing as average student ability moves toward the tails of the achievement distribution. This report examines the variability in…

  19. Evaluating outpatient behavior therapy of sex offenders. A pretest-posttest study.

    PubMed

    Crolley, J; Roys, D; Thyer, B A; Bordnick, P S

    1998-10-01

    This study compared the entrance and exit scores of 16 patients completing treatment at the Highland Institute for Behavioral Change (HIBC), an outpatient program specializing in the behavioral treatment of sex offenders. Outcome measures included the Minnesota Multiphasic Personality Inventory (MMPI), the Multiphasic Sexual Inventory, and recidivism (rearrest record) posttreatment. Statistically significant and clinical improvements were obtained on a number of these measures. One of the 16 graduates reoffended during the average follow-up period of 26 months (he is now incarcerated). These data are supportive of the contention that outpatient behavior therapy can be effective in reducing deviant sexual arousal and in enhancing appropriate consensual sexual behavior.

  20. Vibration training improves disability status in multiple sclerosis: A pretest-posttest pilot study.

    PubMed

    Yang, Feng; Estrada, Edson F; Sanchez, Maria C

    2016-10-15

    The purpose of this study was to examine the effects of an 8-week vibration training program on changing the disability level in people with multiple sclerosis (MS). Twenty-five adults with clinically-confirmed MS underwent an 8-week vibration training on a side-alternating vibration platform. The vibration frequency and peak-to-peak displacement were set at 20Hz and 2.6mm, respectively. Prior to and following the training course, the disability status was assessed for all participants characterized by the Patient Determined Disability Steps (PDDS) and MS Functional Composite (MSFC) scores. The training program significantly improved the PDDS (3.66±1.88 vs. 3.05±1.99, p=0.009) and the MSFC scores (0.00±0.62 vs 0.36±0.68, p<0.0001). All three MSFC components were improved: lower extremity function (9.37±4.92 vs. 8.13±4.08s, p=0.011), upper extremity function (dominant hand: 27.81±5.96 vs. 26.20±5.82s, p=0.053; non-dominant hand: 28.47±7.40 vs. 27.43±8.33s, p=0.059), and cognitive function (30.55±13.54 vs. 36.95±15.07 points, p=0.004). Our findings suggested that vibration training could be a promising alternative modality to reduce the disability level among people with MS. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Measuring pretest-posttest change with a Rasch Rating Scale Model.

    PubMed

    Wolfe, E W; Chiu, C W

    1999-01-01

    When measures are taken on the same individual over time, it is difficult to determine whether observed differences are the result of changes in the person or changes in other facets of the measurement situation (e.g., interpretation of items or use of rating scale). This paper describes a method for disentangling changes in persons from changes in the interpretation of Likert-type questionnaire items and the use of rating scales (Wright, 1996a). The procedure relies on anchoring strategies to create a common frame of reference for interpreting measures that are taken at different times and provides a detailed illustration of how to implement these procedures using FACETS.

  2. Comparing the Effects of Self-Controlled and Examiner-Controlled Feedback on Learning in Children With Developmental Coordination Disorder.

    PubMed

    Zamani, Mohamad Hosein; Fatemi, Rouholah; Soroushmoghadam, Keyvan

    2015-12-01

    Feedback can improve task learning in children with developmental coordination disorder (DCD). However, the frequency and type of feedback may play different role in learning and needs to more investigations. The aim of this study was to evaluate the acquisition and retention of new feedback skills in children with DCD under different frequency of self-control and control examiner feedback. In this quasi-experimental study with pretest-posttest design, participants based on their retention were divided into four feedback groups: self-controlled feedback groups with frequencies of 50% and75%, experimenter controls with frequencies of 50% and 75%. The study sample consisted of 24 boys with DCD aged between 9 to 11 years old in Ahvaz City, Iran. Then subjects practiced 30 throwing (6 blocks of 5 attempts) in eighth session. Acquisition test immediately after the last training session, and then the retention test were taken. Data were analyzed using the paired t-test, ANOVA and Tukey tests. The results showed no significant difference between groups in the acquisition phase (P > 0.05). However,in the retention session, group of self-control showed better performance than the control tester group (P < 0.05). Based on the current findings, self-control feedback with high frequency leads to more learning in DCD children. The results of this study can be used in rehabilitation programs to improve performance and learning in children with DCD.

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

    PubMed

    Jones, Jennifer D

    2006-01-01

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

  4. X-38 Experimental Controls Laws

    NASA Technical Reports Server (NTRS)

    Munday, Steve; Estes, Jay; Bordano, Aldo J.

    2000-01-01

    X-38 Experimental Control Laws X-38 is a NASA JSC/DFRC experimental flight test program developing a series of prototypes for an International Space Station (ISS) Crew Return Vehicle, often called an ISS "lifeboat." X- 38 Vehicle 132 Free Flight 3, currently scheduled for the end of this month, will be the first flight test of a modem FCS architecture called Multi-Application Control-Honeywell (MACH), originally developed by the Honeywell Technology Center. MACH wraps classical P&I outer attitude loops around a modem dynamic inversion attitude rate loop. The dynamic inversion process requires that the flight computer have an onboard aircraft model of expected vehicle dynamics based upon the aerodynamic database. Dynamic inversion is computationally intensive, so some timing modifications were made to implement MACH on the slower flight computers of the subsonic test vehicles. In addition to linear stability margin analyses and high fidelity 6-DOF simulation, hardware-in-the-loop testing is used to verify the implementation of MACH and its robustness to aerodynamic and environmental uncertainties and disturbances.

  5. Experimental research control software system

    NASA Astrophysics Data System (ADS)

    Cohn, I. A.; Kovalenko, A. G.; Vystavkin, A. N.

    2014-05-01

    A software system, intended for automation of a small scale research, has been developed. The software allows one to control equipment, acquire and process data by means of simple scripts. The main purpose of that development is to increase experiment automation easiness, thus significantly reducing experimental setup automation efforts. In particular, minimal programming skills are required and supervisors have no reviewing troubles. Interactions between scripts and equipment are managed automatically, thus allowing to run multiple scripts simultaneously. Unlike well-known data acquisition commercial software systems, the control is performed by an imperative scripting language. This approach eases complex control and data acquisition algorithms implementation. A modular interface library performs interaction with external interfaces. While most widely used interfaces are already implemented, a simple framework is developed for fast implementations of new software and hardware interfaces. While the software is in continuous development with new features being implemented, it is already used in our laboratory for automation of a helium-3 cryostat control and data acquisition. The software is open source and distributed under Gnu Public License.

  6. Effectiveness of a role-play simulation program involving the sbar technique: A quasi-experimental study.

    PubMed

    Yu, Mi; Kang, Kyung Ja

    2017-06-01

    Accurate, skilled communication in handover is of high priority in maintaining patients' safety. Nursing students have few chances to practice nurse-to-doctor handover in clinical training, and some have little knowledge of what constitutes effective handover or lack confidence in conveying information. This study aimed to develop a role-play simulation program involving the Situation, Background, Assessment, Recommendation technique for nurse-to-doctor handover; implement the program; and analyze its effects on situation, background, assessment, recommendation communication, communication clarity, handover confidence, and education satisfaction in nursing students. Non-equivalent control-group pretest-posttest quasi-experimental. A convenience sample of 62 senior nursing students from two Korean universities. The differences in SBAR communication, communication clarity, handover confidence, and education satisfaction between the control and intervention groups were measured before and after program participation. The intervention group showed higher Situation, Background, Assessment, Recommendation communication scores (t=-3.05, p=0.003); communication clarity scores in doctor notification scenarios (t=-5.50, p<0.001); and Situation, Background, Assessment, Recommendation education satisfaction scores (t=-4.94, p<0.001) relative to those of the control group. There was no significant difference in handover confidence between groups (t=-1.97, p=0.054). The role-play simulation program developed in this study could be used to promote communication skills in nurse-to-doctor handover and cultivate communicative competence in nursing students. Copyright © 2017. Published by Elsevier Ltd.

  7. The effectiveness of ethics education: a quasi-experimental field study.

    PubMed

    May, Douglas R; Luth, Matthew T

    2013-06-01

    Ethical conduct is the hallmark of excellence in engineering and scientific research, design, and practice. While undergraduate and graduate programs in these areas routinely emphasize ethical conduct, few receive formal ethics training as part of their curricula. The first purpose of this research study was to assess the relative effectiveness of ethics education in enhancing individuals' general knowledge of the responsible conduct of research practices and their level of moral reasoning. Secondly, we examined the effects of ethics education on the positive psychological outcomes of perspective-taking, moral efficacy, moral courage, and moral meaningfulness. To examine our research hypotheses, we utilized a pretest-posttest quasi-experimental design consisting of three ethics education groups (control, embedded modules, and stand-alone courses). Findings revealed that both embedded and stand alone courses were effective in enhancing participants' perspective-taking, moral efficacy, and moral courage. Moral meaningfulness was marginally enhanced for the embedded module condition. Moral judgment and knowledge of responsible conduct of research practices were not influenced by either ethics education condition. Contrary to expectations, stand alone courses were not superior to embedded modules in influencing the positive psychological outcomes investigated. Implications of these findings for future research and practice are discussed.

  8. Family leader empowerment program using participatory learning process for dengue vector control.

    PubMed

    Pengvanich, Veerapong

    2011-02-01

    Assess the performance of the empowerment program using participatory learning process for the control of Dengue vector The program focuses on using the leaders of families as the main executer of the vector control protocol. This quasi-experimental research utilized the two-group pretest-posttest design. The sample group consisted of 120 family leaders from two communities in Mueang Municipality, Chachoengsao Province. The research was conducted during an 8-week period between April and June 2010. The data were collected and analyzed based on frequency, percentage, mean, paired t-test, and independent t-test. The result was evaluated by comparing the difference between the mean prevalence index of mosquito larvae before and after the process implementation in terms of the container index (CI) and the house index (HI). After spending eight weeks in the empowerment program, the family leader's behavior in the aspect of Dengue vector control has improved. The Container Index and the House Index were found to decrease with p = 0.05 statistical significance. The reduction of CI and HI suggested that the program worked well in the selected communities. The success of the Dengue vector control program depended on cooperation and participation of many groups, especially the families in the community When the family leaders have good attitude and are capable of carrying out the vector control protocol, the risk factor leading to the incidence of Dengue rims infection can be reduced.

  9. A quasi-experimental feasibility study to determine the effect of a systematic treatment programme on the scores of the Nottingham Adjustment Scale of individuals with visual field deficits following stroke.

    PubMed

    Taylor, Lisa; Poland, Fiona; Harrison, Peter; Stephenson, Richard

    2011-01-01

    To evaluate a systematic treatment programme developed by the researcher that targeted aspects of visual functioning affected by visual field deficits following stroke. The study design was a non-equivalent control (conventional) group pretest-posttest quasi-experimental feasibility design, using multisite data collection methods at specified stages. The study was undertaken within three acute hospital settings as outpatient follow-up sessions. Individuals who had visual field deficits three months post stroke were studied. A treatment group received routine occupational therapy and an experimental group received, in addition, a systematic treatment programme. The treatment phase of both groups lasted six weeks. The Nottingham Adjustment Scale, a measure developed specifically for visual impairment, was used as the primary outcome measure. The change in Nottingham Adjustment Scale score was compared between the experimental (n = 7) and conventional (n = 8) treatment groups using the Wilcoxon signed ranks test. The result of Z = -2.028 (P = 0.043) showed that there was a statistically significant difference between the change in Nottingham Adjustment Scale score between both groups. The introduction of the systematic treatment programme resulted in a statistically significant change in the scores of the Nottingham Adjustment Scale.

  10. Effect of Oral Health Care Program on Oral Health Status of Elderly People Living in Nursing Homes: a Quasi-experimental Study.

    PubMed

    Ildarabadi, Es-Hagh; Armat, Mohammad Reza; Motamedosanaye, Vahideh; Ghanei, Farzaneh

    2017-12-01

    Oral health of elderly people plays a major role in their overall health and quality of life, and is an integral part of personal care. The aim of this study was to evaluate the effect of implementing the oral health care program (OHCP) on oral health status of elderly people resident in nursing homes. This quasi-experimental study was carried out using a pretest-posttest design on 101 elderly people (46 in the intervention group and 55 in the control group) resident in two randomly selected nursing homes in Mashhad, Iran. In the intervention group, the OHCP was carried out by caregivers for 8 weeks. The control group received routine care. Using the oral health assessment tool, the oral health status of elderly people was assessed in both groups at three times; onset of the study, 4th, and 8th week after the start of the study. The oral health status of the elderly people in both groups was not statistically significantly different at baseline, but it changed significantly at the 4 th , and 8 th weeks (p<.001). The implementation of the OHCP for elderly people resident in nursing homes may improve their oral health status after 4 weeks. It is recommended that OHCP be included in care plans of all nursing homes to improve the elderly people's oral health status.

  11. [Effect of Visiting and a Smartphone Application Based Infection Prevention Education Program for Child Care Teachers: A Non-Randomized Controlled Trial].

    PubMed

    Yang, Yun Jeong; Kwon, In Soo

    2017-12-01

    This study was performed to develop an infection prevention education program for child care teachers and to verify its effects. The study was conducted using a nonequivalent control group with a pretest-posttest design. Four private daycare centers (2 centers per city) that were alike in terms of the number of children by age, number of child care teachers, and child care environment were chosen. Participants were assigned to the experimental group (n=20) or control group (n=20). As a part of the program, visiting education (90 min) was provided in the 1st week, and smartphone application education (10 min) was provided thrice a week, in the 2nd and 3rd weeks. Child care teachers' self-efficacy for infection prevention revealed a significant interaction effect between the group and time of measurement (F=21.62, p<.001). In terms of infection prevention behavior, a significant difference was observed between the experimental and control groups (z=-5.36, p<.001). The program implemented in this study was effective in improving the infection prevention self-efficacy and infection prevention behavior of child care teachers. Thus, this program may be effective in enhancing their infection control. © 2017 Korean Society of Nursing Science

  12. Communication skills course in an Indian undergraduate dental curriculum: a randomized controlled trial.

    PubMed

    Sangappa, Sunila B; Tekian, Ara

    2013-08-01

    This study assessed the impact of a course on communication skills for third-year undergraduate dental students at a dental institute in India. A randomized pretest, posttest controlled trial was conducted with all the students from four cohorts of third-year dental undergraduate students, divided into an intervention group (n=30) and a control group (n=30). The course was developed using Kern's six-step approach to curriculum development. Needs assessment was ascertained, and readings, lectures, and role-plays with real and simulated patients were implemented. Encounters of students during two patient interviews (simulated and real) were rated by two raters using a twenty-seven-item dental consultation communication checklist with a rating scale 0 to 3. Students completed a questionnaire regarding their acceptance of the course. A 2×2 (group × time) ANOVA with group as a between-subjects factor (control vs. experimental) and time as a within-subjects factor (pre vs. post) was performed. The two groups did not differ at pretest but differed significantly at posttest. This study showed that simply attending to patients during a clinical course did not improve professional communication skills. In contrast, the implementation of a course on communication skills did improve the students' dentist-patient interactions. Integrating the teaching and development of a relevant, outcome-based course on communication skills provided clear evidence of communication skills acquisition among these dental students. The course could be introduced in other Indian dental schools.

  13. A quasi-experimental evaluation of a community-based HIV prevention intervention for Mexican American female adolescents: the SHERO's program.

    PubMed

    Harper, Gary W; Bangi, Audrey K; Sanchez, Bernadette; Doll, Mimi; Pedraza, Ana

    2009-10-01

    This article describes a quasi-experimental evaluation of a community-based, culturally and ecologically tailored HIV prevention intervention for Mexican American female adolescents grounded in the AIDS risk reduction model. A total of 378 Mexican American female adolescents (mean age = 15.2) participated in either the nine-session SHERO's (a female-gendered version of the word hero) intervention or a single session information-only HIV prevention intervention. Assessment data were collected at pretest, posttest, and 2-month follow up. Significant improvements across all time points were revealed on measures of self-esteem, condom attitudes, beliefs regarding a woman's control of her sexuality, beliefs regarding sexual assault, perceived peer norms, and HIV/AIDS and STI knowledge. At posttest SHERO's participants were more likely to carry condoms and to report abstaining from vaginal sex in the previous 2 months; and at 2-month follow up they reported using condoms more often in the preceding 2 months and planned on using them more frequently in the coming 2 months. Findings support the development of community-based adolescent HIV prevention interventions that address culturally specific ecological factors.

  14. Taking Control: The Efficacy and Durability of a Peer-Led Uncertainty Management Intervention for People Recently Diagnosed With HIV.

    PubMed

    Brashers, Dale E; Basinger, Erin D; Rintamaki, Lance S; Caughlin, John P; Para, Michael

    2017-01-01

    HIV creates substantial uncertainty for people infected with the virus, which subsequently affects a host of psychosocial outcomes critical to successful management of the disease. This study assessed the efficacy and durability of a theoretically driven, one-on-one peer support intervention designed to facilitate uncertainty management and enhance psychosocial functioning for patients newly diagnosed with HIV. Using a pretest-posttest control group design, 98 participants received information and training in specific communication strategies (e.g., disclosing to friends and family, eliciting social support, talking to health care providers, using the Internet to gather information, and building social networks through AIDS service organizations). Participants in the experimental group attended six 1-hour sessions, whereas control participants received standard of care for 12 months (after which they received the intervention). Over time, participants in the intervention fared significantly better regarding (a) illness uncertainty, (b) depression, and (c) satisfaction with social support than did those in the control group. Given the utility and cost-effectiveness of this intervention and the uncertainty of a multitude of medical diagnoses and disease experiences, further work is indicated to determine how this program could be expanded to other illnesses and to address related factors, such as treatment adherence and clinical outcomes.

  15. A Translational Worksite Diabetes Prevention Trial Improves Psychosocial Status, Dietary Intake, and Step Counts among Employees with Prediabetes: A Randomized Controlled Trial.

    PubMed

    Miller, Carla K; Weinhold, Kellie; Marrero, David G; Nagaraja, Haikady N; Focht, Brian C

    Few worksite trials have examined the impact of diabetes prevention interventions on psychological and behavioral outcomes. Thus, the impact of a worksite lifestyle intervention on psychosocial outcomes, food group intake, and step counts for physical activity (PA) was evaluated. A randomized pretest/posttest control group design with 3-month follow-up was employed from October 2012 to May 2014 at a U.S. university worksite among employees with prediabetes. The experimental group (n=35) received a 16-week group-based intervention while the control group received usual care (n=33). Repeated measures analysis of variance compared the change in outcomes between groups across time. A significant difference occurred between groups post-intervention for self-efficacy associated with eating and PA; goal commitment and difficulty; satisfaction with weight loss and physical fitness; peer social support for healthful eating; generation of alternatives for problem solving; and intake of fruits, meat, fish, poultry, nuts, and seeds (all ps < .05). The experimental group significantly increased step counts post-intervention (p = .0279) and were significantly more likely to report completing their work at study end (p = .0231). The worksite trial facilitated improvement in modifiable psychosocial outcomes, dietary patterns, and step counts; the long-term impact on diabetes prevention warrants further investigation. ClinicalTrials.gov identifier: NCT01682954.

  16. [The effects of a diabetic educational program for coping with problem situation on self-efficacy, self care behaviors, coping and glycemic control in type 2 diabetic patients].

    PubMed

    Ko, Choun Hee; Gu, Mee Ock

    2004-12-01

    This study was conducted to develop and to test the effects of an educational program for coping with problem situations as a nursing intervention in the diabetic patient. A non-equivalent control group pretest-posttest design was used in this study. Data were collected from January to March, 2002. The subjects of the study consisted of 31 diabetic patients(experimental group: 17 patients, control group: 14 patients). The intervention of an educational program for coping with problem situations was applied to the experimental group for 4 weeks (total 8 hours). Data were collected before the educational program, immediately after and 1 months later and were analyzed with repeated measures ANOVA, t-test, and paired t-test. 1. There was a significant difference in self efficacy between the experimental and control groups (F=13.793, p=0.001). 2. There was a significant difference in self care behavior between the experimental and control groups (F=4.583, p=0.041). 3. There was a significant difference in coping behavior of the problem situation between the experimental and control groups (F=62.018, p=0.000). There was a significant difference according to experimental stages (F=4.546, p=0.015) and interaction between education and experimental stages (F=12.039, p=0.000). 4. There was a significant difference in glycemic control between the experimental and control groups (t=-3.112, p=0.004). These results support that a diabetic educational program for coping with problem situations is effective in promoting and maintaining self efficacy, self care behavior, problem coping behaviors and in improving glycemic control. Thus this program can be recommended as an effective nursing intervention of in-depth education for diabetic patient.

  17. Effect of music therapy with emotional-approach coping on preprocedural anxiety in cardiac catheterization: a randomized controlled trial.

    PubMed

    Ghetti, Claire M

    2013-01-01

    Individuals undergoing cardiac catheterization are likely to experience elevated anxiety periprocedurally, with highest anxiety levels occurring immediately prior to the procedure. Elevated anxiety has the potential to negatively impact these individuals psychologically and physiologically in ways that may influence the subsequent procedure. This study evaluated the use of music therapy, with a specific emphasis on emotional-approach coping, immediately prior to cardiac catheterization to impact periprocedural outcomes. The randomized, pretest/posttest control group design consisted of two experimental groups--the Music Therapy with Emotional-Approach Coping group [MT/EAC] (n = 13), and a talk-based Emotional-Approach Coping group (n = 14), compared with a standard care Control group (n = 10). MT/EAC led to improved positive affective states in adults awaiting elective cardiac catheterization, whereas a talk-based emphasis on emotional-approach coping or standard care did not. All groups demonstrated a significant overall decrease in negative affect. The MT/EAC group demonstrated a statistically significant, but not clinically significant, increase in systolic blood pressure most likely due to active engagement in music making. The MT/EAC group trended toward shortest procedure length and least amount of anxiolytic required during the procedure, while the EAC group trended toward least amount of analgesic required during the procedure, but these differences were not statistically significant. Actively engaging in a session of music therapy with an emphasis on emotional-approach coping can improve the well-being of adults awaiting cardiac catheterization procedures.

  18. Systematic instruction for individuals with acquired brain injury: Results of a randomized controlled trial

    PubMed Central

    Powell, Laurie Ehlhardt; Glang, Ann; Ettel, Deborah; Todis, Bonnie; Sohlberg, McKay; Albin, Richard

    2012-01-01

    The goal of this study was to experimentally evaluate systematic instruction compared with trial-and-error learning (conventional instruction) applied to assistive technology for cognition (ATC), in a double blind, pretest-posttest, randomized controlled trial. Twenty-nine persons with moderate-severe cognitive impairments due to acquired brain injury (15 in systematic instruction group; 14 in conventional instruction) completed the study. Both groups received 12, 45-minute individual training sessions targeting selected skills on the Palm Tungsten E2 personal digital assistant (PDA). A criterion-based assessment of PDA skills was used to evaluate accuracy, fluency/efficiency, maintenance, and generalization of skills. There were no significant differences between groups at immediate posttest with regard to accuracy and fluency. However, significant differences emerged at 30-day follow-up in favor of systematic instruction. Furthermore, systematic instruction participants performed significantly better at immediate posttest generalizing trained PDA skills when interacting with people other than the instructor. These results demonstrate that systematic instruction applied to ATC results in better skill maintenance and generalization than trial-and-error learning for individuals with moderate-severe cognitive impairments due to acquired brain injury. Implications, study limitations, and directions for future research are discussed. PMID:22264146

  19. Effectiveness of a community-based program for suicide prevention among elders with early-stage dementia: A controlled observational study.

    PubMed

    Kim, Jong-Pill; Yang, Jinhyang

    The purpose of this study was to develop a small-group-focused suicide prevention program for elders with early-stage dementia and to assess its effects. This was a quasi-experimental study with a control group pretest-posttest design. A total of 62 elders diagnosed with early-stage dementia who were receiving care services at nine daycare centers in J City Korea participated in this study. The experimental group participated in the suicide prevention program twice a week for 5 weeks with a pretest and two posttests The developed suicide prevention program had a significant effect on the perceived health status, social support, depression, and suicidal ideation of elders with early-stage dementia. Nurses should integrate risk factors such as depression and protective factors such as health status and social support into a suicide prevention program. This community-based program in geriatric nursing practice can be effective in preventing suicide among elders with early-stage dementia. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Effects of Experimental Anterior Knee Pain on Muscle Activation During Landing and Jumping Performed at Various Intensities.

    PubMed

    Park, Jihong; Denning, W Matt; Pitt, Jordan D; Francom, Devin; Hopkins, J Ty; Seeley, Matthew K

    2017-01-01

    Although knee pain is common, some facets of this pain are unclear. The independent effects (ie, independent from other knee injury or pathology) of knee pain on neural activation of lower-extremity muscles during landing and jumping have not been observed. To investigate the independent effects of knee pain on lower-extremity muscle (gastrocnemius, vastus medialis, medial hamstrings, gluteus medius, and gluteus maximus) activation amplitude during landing and jumping, performed at 2 different intensities. Laboratory-based, pretest, posttest, repeated-measures design, where all subjects performed both data-collection sessions. Thirteen able-bodied subjects performed 2 different land and jump tasks (forward and lateral) under 2 different conditions (control and pain), at 2 different intensities (high and low). For the pain condition, experimental knee pain was induced via a hypertonic saline injection into the right infrapatellar fat pad. Functional linear models were used to evaluate the influence of experimental knee pain on muscle-activation amplitude throughout the 2 land and jump tasks. Experimental knee pain independently altered activation for all of the observed muscles during various parts of the 2 different land and jump tasks. These activation alterations were not consistently influenced by task intensity. Experimental knee pain alters activation amplitude of various lower-extremity muscles during landing and jumping. The nature of the alteration varies between muscles, intensities, and phases of the movement (ie, landing and jumping). Generally, experimental knee pain inhibits the gastrocnemius, medial hamstring, and gluteus medius during landing while independently increasing activation of the same muscles during jumping.

  1. Impact of a Worksite Diabetes Prevention Intervention on Diet Quality and Social Cognitive Influences of Health Behavior: A Randomized Controlled Trial.

    PubMed

    Miller, Carla K; Weinhold, Kellie R; Nagaraja, Haikady N

    2016-03-01

    To evaluate the impact of a worksite diabetes prevention intervention on secondary outcomes regarding the change in diet quality and components of the Health Action Process Approach (HAPA) theoretical framework. Pretest-posttest control group design with 3-month follow-up. University worksite. Employees aged 18-65 years with prediabetes (n = 68). A 16-week group-based intervention adapted from the Diabetes Prevention Program. Diet quality was assessed using the Alternative Healthy Eating Index 2010; HAPA components were assessed via written questionnaire. Repeated-measures ANOVA compared the between- and within-group change in outcomes across time. Significant difference occurred between groups for the change in consumption of nuts/legumes and red/processed meats postintervention and for fruits at 3-month follow-up (all P < .05); a significant increase in total Alternative Healthy Eating Index 2010 score occurred postintervention in the experimental group (P = .002). The changes in action planning, action self-efficacy, and coping self-efficacy from HAPA were significantly different between groups after the intervention; the change in outcome expectancies was significantly different between groups at 3-month follow-up (all P < .05). The worksite intervention facilitated improvement in diet quality and in planning and efficacious beliefs regarding diabetes prevention. Further research is needed to evaluate the long-term impact of the intervention. Copyright © 2016 Society for Nutrition Education and Behavior. Published by Elsevier Inc. All rights reserved.

  2. Divergence of Scientific Heuristic Method and Direct Algebraic Instruction

    ERIC Educational Resources Information Center

    Calucag, Lina S.

    2016-01-01

    This is an experimental study, made used of the non-randomized experimental and control groups, pretest-posttest designs. The experimental and control groups were two separate intact classes in Algebra. For a period of twelve sessions, the experimental group was subjected to the scientific heuristic method, but the control group instead was given…

  3. Father's Role in Breastfeeding Promotion: Lessons from a Quasi-Experimental Trial in China.

    PubMed

    Su, Min; Ouyang, Yan-Qiong

    2016-04-01

    The aims of this study were to evaluate the effectiveness of an educational intervention involving fathers on breastfeeding initiation and exclusive breastfeeding rate, and to explore mothers' perceptions of their partners' support of breastfeeding. This study was a quasi-experimental pretest-posttest design with two groups. A convenience sample consisting of 72 expectant mothers was recruited. Thirty-six women with their partners were assigned to the intervention group, and 36 women alone were in the control group. Both groups were offered similar education contents, and the intervention group was given additional information on how fathers could support their partners, both emotionally and physically, during the breastfeeding process. Student's t test, chi-square test, and Mann-Whitney U test were used to detect group differences. The prevalence rates of exclusive breastfeeding at 4 months and 6 months of the intervention group were significantly higher than there were in the control group (51.4% and 26.4%, p = 0.034; 40.0% and 17.6%, p = 0.041). Women in the intervention group were less likely to use infant formula at 1 and 6 months postpartum (5.6% and 23.5%, p = 0.032; 20.0% and 44.1%, p = 0.032). Related to the process of breastfeeding, partners in the intervention group supported their partners by taking care of the infant, doing housework, and providing emotional support. Involving the fathers in breastfeeding education could improve the exclusive breastfeeding rate and prolong the duration of exclusive breastfeeding. The mothers appreciated support from the fathers.

  4. Interactive experimenters' planning procedures and mission control

    NASA Technical Reports Server (NTRS)

    Desjardins, R. L.

    1973-01-01

    The computerized mission control and planning system routinely generates a 24-hour schedule in one hour of operator time by including time dimensions into experimental planning procedures. Planning is validated interactively as it is being generated segment by segment in the frame of specific event times. The planner simply points a light pen at the time mark of interest on the time line for entering specific event times into the schedule.

  5. Improving the Cybersecurity of Cyber-Physical Systems Through Behavioral Game Theory and Model Checking in Practice and in Education

    DTIC Science & Technology

    2016-09-15

    pretest - posttest educational experiment with a control group and an original measurement instrument. Details of the treatment, which consisted of...promise of such an approach, a pretest - posttest educational experiment with a control group and an original measurement instrument was conducted...research question, a pretest - posttest experiment with a control group was designed. The research subjects were a representative sample of the

  6. The Effect of Reflexology Applied to Patients with Chronic Obstructive Pulmonary Disease on Dyspnea and Fatigue.

    PubMed

    Polat, Hatice; Ergüney, Seher

    The purpose of this study was to determine the effect of reflexology on reducing dyspnea and fatigue in patients with chronic obstructive pulmonary disease (COPD). The study was conducted as a pretest-posttest experimental design. The population of the study consisted of 60 patients (30 in experimental group and 30 in control group). Patient Description Form, Baseline Dyspnea Index (BDI) and Visual Analogue Scale-Fatigue (VAS-F) were used to collect the data. The difference between pretest-posttest dyspnea and fatigue mean scores of patients in the experimental group was statistically significant (p < .01). The difference between pretest-posttest dyspnea and fatigue mean scores of patients in the control group was statistically insignificant (p > .05). It was determined that the reflexology reduced dyspnea and fatigue in patients with COPD. Complementary methods such as reflexology should be used with pharmacological methods to reduce dyspnea and fatigue of COPD patients.

  7. A Field Experimental Design of a Strengths-Based Training to Overcome Academic Procrastination: Short- and Long-Term Effect.

    PubMed

    Visser, Lennart; Schoonenboom, Judith; Korthagen, Fred A J

    2017-01-01

    This study reports on the effect of a newly developed 4-week strengths-based training approach to overcome academic procrastination, given to first-year elementary teacher education students ( N = 54). The training was based on a strengths-based approach, in which elements of the cognitive behavioral approach were also used. The purpose of the training was to promote awareness of the personal strengths of students who experience academic procrastination regularly and to teach them how to use their personal strengths in situations in which they usually tend to procrastinate. With a pretest-posttest control group design (two experimental groups: n = 31, control group: n = 23), the effect of the training on academic procrastination was studied after 1, 11, and 24 weeks. Results of a one-way analysis of covariance revealed a significant short-term effect of the training. In the long term (after 11 and 24 weeks), the scores for academic procrastination for the intervention groups remained stable, whereas the scores for academic procrastination for the control group decreased to the same level as those of the intervention groups. The findings of this study suggest that a strengths-based approach can be helpful to students at an early stage of their academic studies to initiate their individual process of dealing with academic procrastination. The findings for the long term show the importance of measuring the outcomes of an intervention not only shortly after the intervention but also in the long term. Further research is needed to find out how the short-term effect can be maintained in the long-term.

  8. A Field Experimental Design of a Strengths-Based Training to Overcome Academic Procrastination: Short- and Long-Term Effect

    PubMed Central

    Visser, Lennart; Schoonenboom, Judith; Korthagen, Fred A. J.

    2017-01-01

    This study reports on the effect of a newly developed 4-week strengths-based training approach to overcome academic procrastination, given to first-year elementary teacher education students (N = 54). The training was based on a strengths-based approach, in which elements of the cognitive behavioral approach were also used. The purpose of the training was to promote awareness of the personal strengths of students who experience academic procrastination regularly and to teach them how to use their personal strengths in situations in which they usually tend to procrastinate. With a pretest-posttest control group design (two experimental groups: n = 31, control group: n = 23), the effect of the training on academic procrastination was studied after 1, 11, and 24 weeks. Results of a one-way analysis of covariance revealed a significant short-term effect of the training. In the long term (after 11 and 24 weeks), the scores for academic procrastination for the intervention groups remained stable, whereas the scores for academic procrastination for the control group decreased to the same level as those of the intervention groups. The findings of this study suggest that a strengths-based approach can be helpful to students at an early stage of their academic studies to initiate their individual process of dealing with academic procrastination. The findings for the long term show the importance of measuring the outcomes of an intervention not only shortly after the intervention but also in the long term. Further research is needed to find out how the short-term effect can be maintained in the long-term. PMID:29163317

  9. A Comparison of Performance versus Presentation Based Methods of Instructing Pre-service Teachers in Media Competencies.

    ERIC Educational Resources Information Center

    Mattox, Daniel V., Jr.

    Research compared conventional and experimental methods of instruction in a teacher education media course. The conventional method relied upon factual presentations to heterogeneous groups, while the experimental utilized homogeneous clusters of students and stressed individualized instruction. A pretest-posttest, experimental-control group…

  10. The Effect of Online Collaboration on Middle School Student Science Misconceptions as an Aspect of Science Literacy

    ERIC Educational Resources Information Center

    Wendt, Jillian L.; Rockinson-Szapkiw, Amanda

    2014-01-01

    This quantitative, quasi-experimental pretest/posttest control group design examined the effects of online collaborative learning on middle school students' science literacy. For a 9-week period, students in the control group participated in collaborative face-to-face activities whereas students in the experimental group participated in online…

  11. The Effects of Reading from the Screen on the Reading Motivation Levels of Elementary 5th Graders

    ERIC Educational Resources Information Center

    Aydemir, Zeynep; Ozturk, Ergun

    2012-01-01

    This study aims to explore the effects of reading from the screen on elementary 5th grade students' reading motivation levels. It used the randomized control-group pretest-posttest model, which is a true experimental design. The study group consisted of 60 students, 30 experimental and 30 control, who were attending the 5th grade of a public…

  12. 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…

  13. [Effects of Aromatherapy on Stress Responses, Autonomic Nervous System Activity and Blood Pressure in the Patients Undergoing Coronary Angiography: A Non-Randomized Controlled Trial].

    PubMed

    Song, Eun Jeong; Lee, Mi Young

    2018-02-01

    The purpose of this study was to examine the effects of aromatherapy on stress responses, autonomic nervous system (ANS) activity, and blood pressure in patients hospitalized to receive coronary angiography (CAG). A non-equivalent control group with a pretest-posttest design was used. The subjects were patients admitted to the day angiography room to receive CAG at E University Hospital (34 in the experimental group and 30 in the control group). The experimental group treatment was inhalation of the aroma oil blended with lavender, ylang-ylang, and neroli at a ratio of 4:2:1 twice before and after CAG. The measurements of stress index, ANS activity, and blood pressure were performed 5 times as follows: at admission, at pre-CAG after treatment I, at post-CAG, 2 hours after treatment II, and 4 hours after treatment II. The data were analyzed using the Mann-Whitney U Test and repeated-measures analysis of variance. Significant interactions in the high frequency of ANS (F=5.58, p=.005) were observed between group and time. Stress index (z=2.14, p=.016), systolic blood pressure (z=4.14, p<.005), and diastolic blood pressure (z=3.28, p=.001) were significantly different between the experimental and control groups after 4 hours of treatment II. The findings showed that aromatherapy was not effective before CAG, but was effective after CAG. Therefore, aromatherapy can be used as a nursing intervention for patients receiving CAG. © 2018 Korean Society of Nursing Science.

  14. The Effect of Manipulatives on Mathematics Achievement and Attitudes of Secondary School Students

    ERIC Educational Resources Information Center

    Kontas, Hakki

    2016-01-01

    The purpose of this study is to investigate the effect of manipulatives (concrete learning materials) both on the academic achievement of secondary school students in mathematics and on their attitudes towards mathematics. Pretest-posttest control group experimental model, which is one of the quasi-experimental research designs, was used in the…

  15. The Effect of a Constructivist Learning Environment on the Limit Concept among Mathematics Student Teachers

    ERIC Educational Resources Information Center

    Bukova-Guzel, Esra

    2007-01-01

    The purpose of this study is to design a constructivist learning environment that helps learning the limit concept. The study is a pretest-posttest quasi-experimental research. The control and the experimental groups were chosen from the students attending a calculus course. Worksheets were used to assess students' learning of the limit concept.…

  16. The Impact of Concept Mapping on EFL Learners' Critical Thinking Ability

    ERIC Educational Resources Information Center

    Khodadady, Ebrahim; Ghanizadeh, Afsaneh

    2011-01-01

    The present study investigated the influence of concept mapping as a post-reading strategy on EFL learners' critical thinking ability. The study utilized a pretest-posttest control and experimental group design. To do so, thirty six EFL learners at upper intermediate and advanced levels were randomly assigned to experimental (n=18) and control…

  17. Effect of Cognitive-Behavioral-Theory-Based Skill Training on Academic Procrastination Behaviors of University Students

    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.…

  18. Bridging Gender Gap in the Physics Classroom: The Instructional Method Perspective

    ERIC Educational Resources Information Center

    Obafemi, Deborah T. A.

    2015-01-01

    The study investigated the influence of students' gender on their understanding, application and analysis of Light waves concept in physics in Ikwerre Local Government Area of Rivers State, Nigeria. A quasi-experimental pretest-posttest design comprising of three experimental and one control group was used, each group was taught with a different…

  19. Effect of Pop Music on Students' Attitudes to Music Lessons

    ERIC Educational Resources Information Center

    Özdemir, Gökhan; Çiftçibasi, M. Can

    2017-01-01

    This study aims to identify whether the use of popular music in teaching song creates a significant difference in attitudes of middle school students to music lessons. "Pretest-posttest design" from experimental models was used. The experimental and control groups consists of 8 classes of continuing education from four different middle…

  20. Comparing Multiple Intelligences Approach with Traditional Teaching on Eight Grade Students' Achievement in and Attitudes toward Science

    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…

  1. An Intervention Including an Online Game to Improve Grade 6 Students' Performance in Early Algebra

    ERIC Educational Resources Information Center

    Kolovou, Angeliki; van den Heuvel-Panhuizen, Marja; Koller, Olaf

    2013-01-01

    This study investigated whether an intervention including an online game contributed to 236 Grade 6 students' performance in early algebra, that is, solving problems with covarying quantities. An exploratory quasi-experimental study was conducted with a pretest-posttest-control-group design. Students in the experimental group were asked to solve…

  2. Metro Navigation for the Blind

    ERIC Educational Resources Information Center

    Sanchez, Jaime; Saenz, Mauricio

    2010-01-01

    This study evaluates the impact of using the software program AudioMetro, a tool that supports the orientation and mobility of people who are blind in the Metro system of Santiago de Chile. A quasi-experimental study considering experimental and control groups and using the paired Student's t in a two sample test analysis (pretest-posttest) was…

  3. The Effect of Peer Support on University Level Students' English Language Achievements

    ERIC Educational Resources Information Center

    Sari, Irfan; Çeliköz, Nadir; Ünal, Süleyman

    2017-01-01

    The purpose of the study is to investigate the effect of peer support on university level students' English language achievements. An experimental model with pretest-posttest experimental and control group was used with 800 students who were studying at a university in Istanbul vicinity. As experiment group, 400 students (200 of whom…

  4. Strength training, walking, and social activity improve sleep in nursing home and assisted living residents: randomized controlled trial.

    PubMed

    Richards, Kathy C; Lambert, Corinne; Beck, Cornelia K; Bliwise, Donald L; Evans, William J; Kalra, Gurpreet K; Kleban, Morton H; Lorenz, Rebecca; Rose, Karen; Gooneratne, Nalaka S; Sullivan, Dennis H

    2011-02-01

    To compare the effects of physical resistance strength training and walking (E), individualized social activity (SA), and E and SA (ESA) with a usual care control group on total nocturnal sleep time in nursing home and assisted living residents. Pretest-posttest experimental design with assignment to one of four groups for 7 weeks: E (n=55), SA (n=50), ESA (n=41), and usual care control (n=47). Ten nursing homes and three assisted living facilities. One hundred ninety-three residents were randomly assigned; 165 completed the study. The E group participated in high-intensity physical resistance strength training 3 days a week and on 2 days walked for up to 45 minutes, the SA group received social activity 1 hour daily 5 days a week, the ESA group received both E and SA, and the control group participated in usual activities provided in the homes. Total nocturnal sleep time was measured using 2 nights of polysomnography before and 2 nights of polysomnography after the intervention. Sleep efficiency (SE), non-rapid eye movement (NREM) sleep, rapid eye movement sleep, and sleep onset latency were also analyzed. Total nocturnal sleep time was significantly greater in the ESA group than in the control group (adjusted means 364.2 minutes vs 328.9 minutes), as was SE and NREM sleep. High-intensity physical resistance strength training and walking combined with social activity significantly improved sleep in nursing home and assisted living residents. The interventions by themselves did not have significant effects on sleep in this population. © 2011, Copyright the Authors. Journal compilation © 2011, The American Geriatrics Society.

  5. Empathy for Interpersonal Peace: Effects of Peace Education on Empathy Skills

    ERIC Educational Resources Information Center

    Sagkal, Ali Serdar; Turnuklu, Abbas; Totan, Tarik

    2012-01-01

    The purpose of this research was to examine the effects of Peace Education Program on the sixth grade elementary students' empathy levels. The research was carried out using pretest-posttest control group quasi-experimental design. While Peace Education Program was applied on experiment group; control group has not been provided any treatment. The…

  6. The Effect of Online Collaboration on Adolescent Sense of Community in Eighth-Grade Physical Science

    ERIC Educational Resources Information Center

    Wendt, Jillian L.; Rockinson-Szapkiw, Amanda J.

    2015-01-01

    Using a quasi-experimental, nonequivalent pretest/posttest control group design, the researchers examined the effects of online collaborative learning on eighth-grade student's sense of community in a physical science class. For a 9-week period, students in the control group participated in collaborative activities in a face-to-face learning…

  7. 76 FR 10365 - Agency Information Collection Request. 60-Day Public Comment Request

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-24

    ... research integrity? To answer the first question, a pretest-posttest control group experimental design is... existing syllabus for a research integrity or research ethics course for the treatment group. The control group will use the existing syllabus with no video simulation in class. Participants will be graduate...

  8. 77 FR 2297 - Agency Information Collection Request. 30-Day Public Comment Request

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-17

    ... answer the first question, a pretest-posttest control group experimental design is used to assess the... from the students who participate in the first part of the study. The focus group will last one hour... integrity or research ethics course for the treatment group. The control group will use the existing...

  9. Effect of Group Sandtray Therapy with Preadolescents

    ERIC Educational Resources Information Center

    Flahive, Mon-hsin Wang; Ray, Dee

    2007-01-01

    The effectiveness of group sandtray therapy, a model of play therapy, was evaluated using a pretest-posttest control group design with 56 preadolescents exhibiting behavioral difficulties. The experimental group (n = 28) received sandtray therapy in small groups for 10 weeks while the wait-list control group (n = 28) received no treatment. Results…

  10. Effects of Practical Life Materials on Kindergartners' Fine Motor Skills.

    ERIC Educational Resources Information Center

    Rule, Audrey C.; Stewart, Roger A.

    2002-01-01

    A pretest-posttest control group design was used to measure the effect of practical life materials (e.g., tweezers, tongs, spoons) on kindergarten children's fine motor skill development. Experimental and control group teachers reported equal amounts of fine motor activity in their classrooms; however, significant interaction effects were found…

  11. The Effect of Participation in Perma plus Yoga on Salutogenic Wellness and Flourishing in People over Age 50

    ERIC Educational Resources Information Center

    Allen, Kimberly M.

    2017-01-01

    This quasi-experimental pretest/posttest control group study design evaluated the effects of a multi-component educational intervention on the well-being of older adults. Participants were members of a senior community center in the Midwestern United States. The sample consisted of 45 participants assigned to either a treatment or control group.…

  12. Rethinking Intelligence: The Role of Mindset in Promoting Success for Academically High-Risk Students

    ERIC Educational Resources Information Center

    Sriram, Rishi

    2014-01-01

    This study utilized an experimental pretest-posttest control group design to determine if changing the way academically high-risk college students view intelligence affected their academic effort and achievement when compared to students in a control intervention. Results indicated that students taught to view intelligence as malleable reported…

  13. Impulse damping control of an experimental structure

    NASA Technical Reports Server (NTRS)

    Redmond, J.; Meyer, J. L.; Silverberg, L.

    1993-01-01

    The characteristics associated with the fuel optimal control of a harmonic oscillator are extended to develop a near minimum fuel control algorithm for the vibration suppression of spacecraft. The operation of single level thrusters is regulated by recursive calculations of the standard deviations of displacement and velocity resulting in a bang-off-bang controller. A vertically suspended 16 ft cantilevered beam was used in the experiment. Results show that the structure's response was easily manipulated by minor alterations in the control law and the control system performance was not seriously degraded in the presence of multiple actuator failures.

  14. Experimental Validation of an Integrated Controls-Structures Design Methodology

    NASA Technical Reports Server (NTRS)

    Maghami, Peiman G.; Gupta, Sandeep; Elliot, Kenny B.; Walz, Joseph E.

    1996-01-01

    The first experimental validation of an integrated controls-structures design methodology for a class of large order, flexible space structures is described. Integrated redesign of the controls-structures-interaction evolutionary model, a laboratory testbed at NASA Langley, was described earlier. The redesigned structure was fabricated, assembled in the laboratory, and experimentally tested against the original structure. Experimental results indicate that the structure redesigned using the integrated design methodology requires significantly less average control power than the nominal structure with control-optimized designs, while maintaining the required line-of-sight pointing performance. Thus, the superiority of the integrated design methodology over the conventional design approach is experimentally demonstrated. Furthermore, amenability of the integrated design structure to other control strategies is evaluated, both analytically and experimentally. Using Linear-Quadratic-Guassian optimal dissipative controllers, it is observed that the redesigned structure leads to significantly improved performance with alternate controllers as well.

  15. The Effect of Using Metacognitive Strategies for Solving Geometry Problems on Students' Achievement and Attitude

    ERIC Educational Resources Information Center

    Mandaci Sahin, Seher; Kendir, Fatma

    2013-01-01

    The purpose of this study is to identify the effect of using metacognitive strategies for problem solving in "geometry" on fifth grade students' achievement, metacognitive skills and attitude. Experimental method was used with a pretest/posttest control group design. Firstly, both groups were subject to a pretest that was comprised of…

  16. A Study on Gross Motor Skills of Preschool Children

    ERIC Educational Resources Information Center

    Wang, Joanne Hui-Tzu

    2004-01-01

    The purpose of this study was to investigate the effects of a creative movement program on gross motor skills of preschool children. Sixty children between the ages of 3 to 5 were drawn from the population of a preschool in Taichung, Taiwan. An experimental pretest-posttest control-group design was utilized. The children enrolled in the…

  17. The Effect of Diffused Aromatherapy on Test Anxiety among Baccalaureate Nursing Students

    ERIC Educational Resources Information Center

    Johnson, Catherine E.

    2013-01-01

    A quantitative, randomized, pretest, posttest study was conducted to assess the effect of aromatherapy on cognitive test anxiety among nursing students. Sophomore nursing students (n = 39) from a private, 4-year college, were randomized into either the control group (n = 18) or the experimental group (n = 21). Each participant completed the…

  18. The Effect of Blog Use on Self-Regulatory Learning of Prospective German Language Teachers

    ERIC Educational Resources Information Center

    Seyhan Yucel, Mukadder

    2013-01-01

    The purpose of the study was to examine the effect of blog use on self-regulatory learning of prospective German language teachers. The study is semi-experimental. Pretest-posttest, experiment control model was used. Blog activities were conducted as extensive beyond classroom activities only for the experiment group. As the data collection tool…

  19. Impact of Integrated Science and English Language Arts Literacy Supplemental Instructional Intervention on Science Academic Achievement of Elementary Students

    ERIC Educational Resources Information Center

    Marks, Jamar Terry

    2017-01-01

    The purpose of this quasi-experimental, nonequivalent pretest-posttest control group design study was to determine if any differences existed in upper elementary school students' science academic achievement when instructed using an 8-week integrated science and English language arts literacy supplemental instructional intervention in conjunction…

  20. Effect of Drama Instruction Method on Students' Turkish Verbal Skills and Speech Anxiety

    ERIC Educational Resources Information Center

    Kardas, Mehmet Nuri; Koç, Rasit

    2017-01-01

    The objective of the present study is to determine the effect of the "drama" method on students' Turkish verbal skills and speech anxiety. Pretest-posttest experimental model with control group was utilized in the study. In the analysis of data obtained by Turkish Rhetorical Skills Scale (TRSS) and Speech Anxiety Scale (SAS), t-test…

  1. Effectiveness of Mind Mapping in English Teaching among VIII Standard Students

    ERIC Educational Resources Information Center

    Hallen, D.; Sangeetha, N.

    2015-01-01

    The aim of the study is to find out the effectiveness of mind mapping technique over conventional method in teaching English at high school level (VIII), in terms of Control and Experimental group. The sample of the study comprised, 60 VIII Standard students in Tiruchendur Taluk. Mind Maps and Achievement Test (Pretest & Posttest) were…

  2. Mathematical Critical Thinking and Curiosity Attitude in Problem Based Learning and Cognitive Conflict Strategy: A Study in Number Theory Course

    ERIC Educational Resources Information Center

    Zetriuslita; Wahyudin; Jarnawi

    2017-01-01

    This research aims to describe and analyze result of applying Problem-Based Learning and Cognitive Conflict Strategy (PBLCCS) in increasing students' Mathematical Critical Thinking (MCT) ability and Mathematical Curiosity Attitude (MCA). Adopting a quasi-experimental method with pretest-posttest control group design and using mixed method with…

  3. Instruction of Learning Strategies: Effects on Conceptual Learning, and Learning Satisfactions

    ERIC Educational Resources Information Center

    Caliskan, Serap

    2011-01-01

    This study has investigated the effects of learning strategy instruction on conceptual learning, and student satisfactions in an introductory physics course at university level. In this study, pretest-posttest and quasi-experimental design with a non-equivalent control group was used. A total of 36 sophomore students majoring in mathematics…

  4. Effects of Prior Knowledge of Topics and the Instructional Objectives on Students' Achievement in Literature-in-English

    ERIC Educational Resources Information Center

    Mbah, Blessing Akaraka

    2015-01-01

    This study investigated the effects of prior knowledge of topics with their instructional objectives on senior secondary school class two (SS II) students. The study was carried out in Abakaliki Education Zone of Ebonyi State, Nigeria. The design of the study is quasi experimental of pretest-posttest of non-equivalent control group. Two research…

  5. The Effects of Learning-Style Based Activities on Students' Reading Comprehension Skills and Self-Efficacy Perceptions in English Foreign Language Classes

    ERIC Educational Resources Information Center

    Balci, Özgül

    2017-01-01

    This study investigated the effects of learning-style based activities on students' reading comprehension skills and self-efficacy perceptions in English foreign language classes. A quasi-experimental, matching-only pretest-posttest control group design was utilized. The study was conducted with freshmen university students majoring in Elementary…

  6. Third Graders Explore Sound Concepts through Online Research Compared to Making Musical Instruments

    ERIC Educational Resources Information Center

    Borsay, Kyrie D.; Foss, Page

    2016-01-01

    This study is an exploration of several lessons on sound taught to third grade students using one of the Next Generation Science Standards (3-5-ETS1) and arts integration. A counterbalanced, pretest- posttest- distal posttest design experiment was conducted to compare student knowledge and attitudes between the control and experimental conditions.…

  7. The Effects of Performance Assessment Approach on Democratic Attitude of Students

    ERIC Educational Resources Information Center

    Yalcinkaya, Elvan

    2013-01-01

    The aim of the research is to analyze the effects of performance assessment approach on democratic attitude of students. The research model is an experimental design with pretest-posttest control groups. Both quantitative and qualitative techniques are used for gathering of data in this research. 46 students participated in this research, with 23…

  8. The Effects of Scenario Planning on Participant Reports of Resilience

    ERIC Educational Resources Information Center

    Chermack, Thomas J.; Coons, Laura M.; O'barr, Gregory; Khatami, Shiva

    2017-01-01

    Purpose: The purpose of this research is to examine the effects of scenario planning on participant ratings of resilience. Design/methodology/approach: The research design is a quasi experimental pretest/posttest with treatment and control groups. Random selection or assignment was not achieved. Findings: Results show a significant difference in…

  9. 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…

  10. The Challenge of Promoting Self-Regulated Learning among Primary School Children with a Low Socioeconomic and Immigrant Background

    ERIC Educational Resources Information Center

    Vandevelde, Sabrina; Van Keer, Hilde; Merchie, Emmelien

    2017-01-01

    The authors explore the effects of student tutoring as an approach to provide support on self-regulated learning (SRL) to fifth- and sixth-grade students with a low socioeconomic or immigrant background. In total, 401 Flemish (Belgium) students participated. A quasi-experimental study with pretest, posttest, and retention test control group design…

  11. Effect of Stress-Response Psycho-Training on the Stress Levels of Mothers with Autistic Children

    ERIC Educational Resources Information Center

    Karaman, Ömer

    2018-01-01

    The aim of the study was to assess the effect of stress-response psycho-training on the stress levels of mothers with autistic children. The research was experimental in design encompassing a pretest-posttest model with control and placebo groups. Participation in the study was voluntary with a total of 28 mothers of autistic children included…

  12. An Evaluation of Nutrition Education Program for Low-Income Youth

    ERIC Educational Resources Information Center

    Kemirembe, Olive M. K.; Radhakrishna, Rama B.; Gurgevich, Elise; Yoder, Edgar P.; Ingram, Patreese D.

    2011-01-01

    A quasi-experimental design consisting of pretest, posttest, and delayed posttest comparison control group was used. Nutrition knowledge and behaviors were measured at pretest (time 1) posttest (time 2) and delayed posttest (time 3). General Linear Model (GLM) repeated measure ANCOVA results showed that youth who received nutrition education…

  13. Evaluating the Effectiveness of Computer Applications in Developing English Learning

    ERIC Educational Resources Information Center

    Whitaker, James Todd

    2016-01-01

    I examined the effectiveness of self-directed learning and English learning with computer applications on college students in Bangkok, Thailand, in a control-group experimental-group pretest-posttest design. The hypothesis was tested using a t test: two-sample assuming unequal variances to establish the significance of mean scores between the two…

  14. The Influence of Choice Theory Anger Management Program (CTAMP) on the Ability of Prospective Psychological Counselors for Anger Management

    ERIC Educational Resources Information Center

    Gündogdu, Rezzan

    2018-01-01

    This research is a quasi-experimental study with pretest-posttest-fallow up test and experiment-control group to investigate the influence of Choice Theory-based Anger Management Psychoeducation Program (CTAMP) on the ability of students of Department of Psychological Counseling and Guidance (PCG) for anger management. The Trait Anger-Anger Style…

  15. Effects of Cloze Instructional Approach on Senior Secondary School Students' Achievement in Igbo Language Reading Comprehension

    ERIC Educational Resources Information Center

    Eze, Nneka Justina

    2015-01-01

    This study assessed the effects of cloze instructional approach on senior secondary school students' achievement in Igbo language reading comprehension. The study utilized a quasi experimental research design of the pretest posttest non-equivalent control group design. The study was conducted in Abakaliki education zone of Ebonyi State of Nigeria.…

  16. Effects of Concept Mapping Instruction Approach on Students' Achievement in Basic Science

    ERIC Educational Resources Information Center

    Ogonnaya, Ukpai Patricia; Okafor, Gabriel; Abonyi, Okechukwu S.; Ugama, J. O.

    2016-01-01

    The study investigated the effects of concept mapping on students' achievement in basic science. The study was carried out in Ebonyi State of Nigeria. The study employed a quasi-experimental design. Specifically the pretest posttest non-equivalent control group research design was used. The sample was 122 students selected from two secondary…

  17. Expanding Training Opportunities for Parents of Children with Autism

    ERIC Educational Resources Information Center

    Suppo, Jennifer L.; Mayton, Michael R.

    2014-01-01

    The purpose of this study was to demonstrate that parents who have children diagnosed with autism can learn and accurately apply knowledge regarding a research-based practice for their children by utilizing a prescribed, self-directed, online program. Using a quasi-experimental, non-equivalent control group, pretest-posttest design, this study…

  18. Debate Instruction in EFL Classroom: Impacts on the Critical Thinking and Speaking Skill

    ERIC Educational Resources Information Center

    Iman, Jaya Nur

    2017-01-01

    The research was aimed to find out whether or not using debate significantly improved the students' critical thinking and speaking skill achievements and how much debate contributed to each aspect of critical thinking and speaking skill. A quasi-experimental study of non-equivalent pretest- posttest control group design was used in this research.…

  19. Effects of Mathematical Vocabulary Instruction on Students' Achievement in Mathematics in Secondary Schools of Murang'a County, Kenya

    ERIC Educational Resources Information Center

    Wanjiru, Benson; O-Connor, Miheso

    2015-01-01

    This article is based on a study whose main objective was to determine the effects of mathematical vocabulary instruction on students' achievement in Mathematics in Secondary schools in Murang'a County, Kenya. The study was a non-equivalent control group pretest-posttest quasi-experimental design and was conducted in the two purposively selected…

  20. The Effects of a Mobile Gamification App on Elementary Students' Spanish Achievement and Self-Efficacy

    ERIC Educational Resources Information Center

    Rachels, Jason R.; Rockinson-Szapkiw, Amanda J.

    2018-01-01

    A quasi-experimental, pretest-posttest, non-equivalent control group design was used to examine the effect of a mobile gamification application on third and fourth grade students' Spanish language achievement and student academic self-efficacy. In this study, the treatment group's Spanish language instruction was through the use of…

  1. Difference among Levels of Inquiry: Process Skills Improvement at Senior High School in Indonesia

    ERIC Educational Resources Information Center

    Hardianti, Tuti; Kuswanto, Heru

    2017-01-01

    The objective of the research concerned here was to discover the difference in effectiveness among Levels 2, 3, and 4 of inquiry learning in improving students' process skills. The research was a quasi-experimental study using the pretest-posttest non-equivalent control group research design. Three sample groups were selected by means of cluster…

  2. Comparison of Effects of Teaching English to Thai Undergraduate Teacher-Students through Cross-Curricular Thematic Instruction Program Based on Multiple Intelligence Theory and Conventional Instruction

    ERIC Educational Resources Information Center

    Rattanavich, Saowalak

    2013-01-01

    This study is aimed at comparing the effects of teaching English to Thai undergraduate teacher-students through cross-curricular thematic instruction program based on multiple intelligence theory and through conventional instruction. Two experimental groups, which utilized Randomized True Control Group-Pretest-posttest Time Series Design and…

  3. Effects of a Computer-Based Early Reading Program on the Early Reading and Oral Language Skills of At-Risk Preschool Children

    ERIC Educational Resources Information Center

    Huffstetter, Mary; King, James R.; Onwuegbuzie, Anthony J.; Schneider, Jenifer J.; Powell-Smith, Kelly A.

    2010-01-01

    This study examined the effects of a computer-based early reading program (Headsprout Early Reading) on the oral language and early reading skills of at-risk preschool children. In a pretest-posttest control group design, 62 children were randomly assigned to receive supplemental instruction with Headsprout Early Reading (experimental group) or…

  4. Effects of Video-Based Cooperative, Competitive and Individualized Instructional Strategies on the Performance of Senior Secondary Schools Students in Geometry

    ERIC Educational Resources Information Center

    Gambari, Amosa Isiaka; Shittu, Ahmed Tajudeen; Daramola, Florence Olutunu; James, Moses

    2016-01-01

    This study examined the effects of video-based cooperative, competitive and individualized instructional strategies on the performance of senior secondary schools' students in geometry in Nigeria. It also examined the influence of gender on students' achievement. Pretest, posttest, experimental control group design was adopted for this study.…

  5. Online Case-Based Learning Design for Facilitating Classroom Teachers' Development of Technological, Pedagogical, and Content Knowledge

    ERIC Educational Resources Information Center

    Saltan, Fatih

    2017-01-01

    The aim of this study is to investigate whether, and if so how, online case-based learning influence pre-service classroom teachers' self-confidence on technological pedagogical content knowledge (TPACK). To achieve the goal, a control group pretest-posttest quasi experimental design was used. Participants of the study consisted of 160 pre-service…

  6. Effects of Screencasting on the Turkish Undergraduate Students' Achievement and Knowledge Acquisitions in Spreadsheet Applications

    ERIC Educational Resources Information Center

    Tekinarslan, Erkan

    2013-01-01

    The purpose of this study is to investigate the effects of screencasts on the Turkish undergraduate students' achievement and knowledge acquisitions in spreadsheet applications. The methodology of the study is based on a pretest-posttest experimental design with a control group. A total of 66 undergraduate students in two groups (n = 33 in…

  7. Effectiveness of Virtual Worlds in Public Health Preparedness Training

    ERIC Educational Resources Information Center

    Earley, Elvia A.

    2012-01-01

    In emergency response training, it is essential that the learners are able to apply their classroom knowledge and implement the practical and critical thinking skills they learned. A quasi-experimental methodology with a non-randomized control group and a pretest-posttest was used in this study to evaluate the training level of satisfaction as a…

  8. Problem-Based Instructional Strategy and Numerical Ability as Determinants of Senior Secondary Achievement in Mathematics

    ERIC Educational Resources Information Center

    Badru, Ademola K.

    2016-01-01

    The study investigated Problem-based Instructional Strategy and Numerical ability as determinants of Senior Secondary Achievement in Mathematics. This study used 4 x 2 x 2 non-randomised control group Pretest-Posttest Quasi-experimental Factorial design. It consisted of two independent variables (treatment and Numerical ability) and one moderating…

  9. The Influence of Reflection on Employee Psychological Empowerment: Report of an Exploratory Workplace Field Study

    ERIC Educational Resources Information Center

    Cyboran, Vincent L.

    2005-01-01

    The study examined the influences of reflection on the self-perception of empowerment in the workplace. The convenience sample consisted of non-management knowledge workers at a software company headquartered in the United States. A pretest, posttest control group design was used. The experimental group kept guided journals of their learning…

  10. Becoming Critical Thinkers: The Impact of Treatments on Student Reflective Practice in the College Classroom

    ERIC Educational Resources Information Center

    Depinet, Andrea

    2012-01-01

    The purpose of the study was to determine the effect of instructional treatments on reflective practice and critical thinking in the college classroom at Bowling Green State University in the College of Business. The study employed a quasi-experimental pretest posttest control group design to examine student reflective practice among three…

  11. Effects of Classification Exposure upon Numerical Achievement of Educable Mentally Retarded Children.

    ERIC Educational Resources Information Center

    Funk, Kerri L.; Tseng, M. S.

    Two groups of 32 educable mentally retarded children (ages 7 to 14 years) were compared as to their arithmetic and classification performances attributable to the presence or absence of a 4 1/2 week exposure to classification tasks. The randomized block pretest-posttest design was used. The experimental group and the control group were matched on…

  12. Integrating Reform-Oriented Math Instruction in Special Education Settings

    ERIC Educational Resources Information Center

    Bottge, Brian A.; Rueda, Enrique; LaRoque, Perry T.; Serlin, Ronald C.; Kwon, Jungmin

    2007-01-01

    This mixed-methods study assessed the effects of Enhanced Anchored Instruction (EAI) on the math performance of adolescents with learning disabilities in math (MLD). A quasi-experimental pretest-posttest control group design with switching replications was used to measure students' computation and problem-solving skills on EAI compared to control…

  13. Effect of Modeling-Based Activities Developed Using Virtual Environments and Concrete Objects on Spatial Thinking and Mental Rotation Skills

    ERIC Educational Resources Information Center

    Yurt, Eyup; Sunbul, Ali Murat

    2012-01-01

    In this study, the effect of modeling based activities using virtual environments and concrete objects on spatial thinking and mental rotation skills was investigated. The study was designed as a pretest-posttest model with a control group, which is one of the experimental research models. The study was carried out on sixth grade students…

  14. The Effect of Given Homework upon the Instruction of Self-Regulation Strategies That Were Directed to Develop Self-Regulation Strategies

    ERIC Educational Resources Information Center

    Eker, Cevat

    2013-01-01

    The aim of this study is to specify the effect of self-regulation strategies upon the instruction of secondary school 5th grade students, whom were given homework to do. In this research, pretest - posttest control group design of experimental method was used. Self-Regulation Learning Strategies Scale (SRLSS), the sub-dimension of the Motivated…

  15. The Effect of Lego Mindstorms Ev3 Based Design Activities on Students' Attitudes towards Learning Computer Programming, Self-Efficacy Beliefs and Levels of Academic Achievement

    ERIC Educational Resources Information Center

    Korkmaz, Özgen

    2016-01-01

    The aim of the study was to present the effect of Lego Mindstorms Ev3 based design activities on students' attitudes towards learning computer programming, self-efficacy beliefs and levels of academic achievement. The research is a pretest-posttest with control group semi-experimental study. The study group of the research consisted of 53 students…

  16. Effects of Metacognitive Guidance on Critical Thinking Disposition

    ERIC Educational Resources Information Center

    Akyüz, Halil Ibrahim; Samsa Yetik, Serap; Keser, Hafize

    2015-01-01

    The present study investigated the effect of metacognitive guidance in an online learning environment on the students' critical thinking competency. The research was carried out using experimental design with pretest-posttest control groups. The research group of the study consisted of 60 students studying at Computer and Educational Teaching…

  17. Effect of Strategy Teaching for the Solution of Ratio Problems on Students' Proportional Reasoning Skills

    ERIC Educational Resources Information Center

    Sen, Ceylan; Güler, Gürsel

    2017-01-01

    The study was conducted to reveal the effects of the instruction of different problem-solving strategies on the proportional reasoning skills of students in solving proportional problems in the 6th grade math's class. Quasi-experimental research model with pretest-posttest control group was employed in the study. For eight class hours, the…

  18. The Effect of Fine Motor Skill Activities on Kindergarten Student Attention

    ERIC Educational Resources Information Center

    Stewart, Roger A.; Rule, Audrey C.; Giordano, Debra A.

    2007-01-01

    This study explored the effect of fine motor skill activities on the development of attention in kindergarteners (n = 68) in five classes at a suburban public school in the Intermountain West through a pretest/posttest experimental group (n = 36) control group (n = 32) design. All children received the regular curriculum which included typical…

  19. Improving Primary Teachers' Attitudes toward Science by Attitude-Focused Professional Development

    ERIC Educational Resources Information Center

    van Aalderen-Smeets, Sandra I.; van der Molen, Juliette H. Walma

    2015-01-01

    This article provides a description of a novel, attitude-focused, professional development intervention, and presents the results of an experimental pretest-posttest control group study investigating the effects of this intervention on primary teachers' personal attitudes toward science, attitudes toward teaching science, and their science…

  20. Analyzing the Efficiency of Argumentation Based Practices on 9th Grade Functions Subject

    ERIC Educational Resources Information Center

    Mercan, Emel; Isleyen, Tevfik

    2017-01-01

    The purpose of this study is to investigate the effect of teaching 9th grade Functions subject through argumentation on students' science process skills, attitudes towards Maths, willingness for argumentation and conceptual comprehension. The study was designed as a quasi-experimental model with pretest-posttest control group. It was carried out…

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

    ERIC Educational Resources Information Center

    Gbore, Lawrence Olu; Osakuade, Joseph Oluwatayo

    2016-01-01

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

  2. The Effect of Electronic Dialogue Journaling on Jordanian Basic Stage EFL Students' Writing Performance

    ERIC Educational Resources Information Center

    El-Koumy, Abdel Salam Abdel Khalek; Mirjan, Zahra' Imad

    2008-01-01

    This study aimed at investigating the effect of electronic dialogue journaling on Jordanian upper basic stage EFL students' writing performance. The study utilized a pretest-posttest control group experimental design. The subjects of the study consisted of fifty students enrolled in the Islamic Educational School during the first semester of the…

  3. Addressing the Needs of Students with Learning Disabilities during Their Interaction with the Web

    ERIC Educational Resources Information Center

    Curcic, Svjetlana

    2011-01-01

    Purpose: The purpose of this study is to examine the effectiveness of instruction in information problem solving within the world wide web (the web) environment. The participants were 20 seventh and eighth grade students with a learning disability (LD) in reading. An experimental pretest-posttest control group method was used to investigate the…

  4. Investigating the Effectiveness of Storylines Embedded within a Context-Based Approach: The Case for the Periodic Table

    ERIC Educational Resources Information Center

    Demircioglu, Hulya; Demircioglu, Gokhan; Calik, Muammar

    2009-01-01

    We investigated the effect of the context-based approach on 9th grade students' conceptions of the Periodic Table. Within a nonequivalent pretest-posttest control group design the study was conducted with 80 grade 9 students (aged 15-16) drawn from two classes (39 and 41 students) in a high school in Turkey. The experimental group was exposed to…

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

    ERIC Educational Resources Information Center

    Trochim, William M. K.; And Others

    1991-01-01

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

  6. Assessing the Effectiveness of a 3-D Instructional Game on Improving Mathematics Achievement and Motivation of Middle School Students

    ERIC Educational Resources Information Center

    Bai, Haiyan; Pan, Wei; Hirumi, Astusi; Kebritchi, Mansureh

    2012-01-01

    This research study assessed the effectiveness of a three-dimensional mathematics game, DimensionM, through a pretest-posttest control group quasi-experimental design. Participants consisted of 437 eighth graders. The classrooms were randomly assigned either to the treatment group that utilized DimensionM as a supplement to regular classroom…

  7. Building Student Understanding of the Cause of Day and Night: A Study of Literacy- and Spatial Thinking-Integrated Activities Compared to a Commercial Curriculum

    ERIC Educational Resources Information Center

    Rule, Audrey C.; Webb, Angela Naomi

    2015-01-01

    The cause of day and night is a difficult concept to master without concrete foundational skills of understanding shadows, rotation, changing point of view, and relative positions of objects in the sky. This pretest-posttest experimental-control group study examined student learning in a science-literacy-spatial skills integrated unit with…

  8. The Effects of Using an Interactive Whiteboard on the Academic Achievement of University Students

    ERIC Educational Resources Information Center

    Akbas, Oktay; Pektas, Huseyin Mirac

    2011-01-01

    The aim of this study was to identify the effects of the use of an interactive whiteboard on the academic achievement of university students on the topic of electricity in a science and technology laboratory class. The study was designed as a pretest/posttest control group experimental study. Mean, standard deviation and t- tests were used for…

  9. The Effect of Using the Creative Reversal Act in Science Education on Middle School Students' Creativity Levels

    ERIC Educational Resources Information Center

    Karaca, Tulin; Koray, Ozlem

    2017-01-01

    Purpose: The purpose of this study is to examine the effects of the creative reversal act (CREACT) used in teaching ecosystems topics on the creativity levels of middle school students. Research Methods: The research was conducted using a quasi-experimental design, a quantitative research method, and a pretest-posttest control group design. The…

  10. Enhancing Critical Thinking Skills and Writing Skills through the Variation in Non-Traditional Writing Task

    ERIC Educational Resources Information Center

    Sinaga, Parlindungan; Feranie, Shelly

    2017-01-01

    The research aims to identify the impacts of embedding non-traditional writing tasks within the course of modern physics conducted to the students of Physics Education and Physics Study Programs. It employed a quasi-experimental method with the pretest-posttest control group design. The used instruments were tests on conceptual mastery, tests on…

  11. Primary Teachers Conducting Inquiry Projects: Effects on Attitudes towards Teaching Science and Conducting Inquiry

    ERIC Educational Resources Information Center

    van Aalderen-Smeets, Sandra I.; Walma van der Molen, Juliette H.; van Hest, Erna G. W. C. M.; Poortman, Cindy

    2017-01-01

    This study used an experimental, pretest-posttest control group design to investigate whether participation in a large-scale inquiry project would improve primary teachers' attitudes towards teaching science and towards conducting inquiry. The inquiry project positively affected several elements of teachers' attitudes. Teachers felt less anxious…

  12. The Effect of Planetarium Trip on Pre-Service Science Teachers' Metaphorical Perceptions about Planetariums

    ERIC Educational Resources Information Center

    Bozdogan, Aykut Emre

    2016-01-01

    The study aimed at examining the effect of the planetarium trip on metaphors developed by the pre-service science teachers about the concept of planetarium. Within this context of the study, a trip was organized to Ondokuz Mayis University (OMU) Planetarium. Pretest-posttest control group design, one of the experimental designs, was used in the…

  13. Evaluating Effect of Students' Academic Achievement on Identified Difficult Concepts in Senior Secondary School Biology in Delta State

    ERIC Educational Resources Information Center

    Agboghoroma, Tim E.; Oyovwi, E. O.

    2015-01-01

    This study evaluated the effect of students' academic achievement on identified difficult concepts or topics in Senior Secondary School Biology in Delta State, Nigeria. The study was quasi-experimental and the design was a 2X2 factorial non-randomized pretest-posttest control group design. The sample was drawn from intact classes from four…

  14. Investigating the Effectiveness of Audio Input Enhancement on EFL Learners' Retention of Intensifiers

    ERIC Educational Resources Information Center

    Negari, Giti Mousapour; Azizi, Aliye; Arani, Davood Khedmatkar

    2018-01-01

    The present study attempted to investigate the effects of audio input enhancement on EFL learners' retention of intensifiers. To this end, two research questions were formulated. In order to address these research questions, this study attempted to reject two null hypotheses. Pretest-posttest control group quasi-experimental design was employed to…

  15. The Effect of Various Media Scaffolding on Increasing Understanding of Students' Geometry Concepts

    ERIC Educational Resources Information Center

    Sutiarso, Sugeng; Coesamin, M.; Nurhanurawati

    2018-01-01

    This study is a quasi-experimental research with pretest-posttest control group design, which aims to determine (1) the tendency of students in using various media scaffolding based on gender, and (2) effect of media scaffolding on increasing understanding of students' geometry concepts. Media scaffolding used this study is chart, props, and…

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

    ERIC Educational Resources Information Center

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

    2017-01-01

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

  17. The Effect of Online Collaborative Learning on Middle School Student Science Literacy and Sense of Community

    ERIC Educational Resources Information Center

    Wendt, Jillian Leigh

    2013-01-01

    This study examines the effects of online collaborative learning on middle school students' science literacy and sense of community. A quantitative, quasi-experimental pretest/posttest control group design was used. Following IRB approval and district superintendent approval, students at a public middle school in central Virginia completed a…

  18. The Effectiveness of Advance Organiser Model on Students' Academic Achievement in Learning Work and Energy

    ERIC Educational Resources Information Center

    Gidena, Asay; Gebeyehu, Desta

    2017-01-01

    The purpose of this study was to investigate the effectiveness of the advance organiser model (AOM) on students' academic achievement in learning work and energy. The design of the study was quasi-experimental pretest-posttest nonequivalent control groups. The total population of the study was 139 students of three sections in Endabaguna…

  19. The Effect of the Activities Enhanced Concerning Time Concept on Time Concept Acquisition of Children

    ERIC Educational Resources Information Center

    Birgül, Arzu Ergisi; Zeteroglu, Elvan Sahin; Derman, Meral Taner

    2017-01-01

    The aim of this study is to examine the effect of the activities enhanced concerning time concept on time concept acquisition of children. The research is a quantitative study in experimental model with pretest-posttest control group aiming to examine the effect of the activities enhanced concerning time concept on time concept acquisition of…

  20. The Effect of Classroom Walkthroughs on Middle School Teacher Motivation

    ERIC Educational Resources Information Center

    Dickenson, Karen Nadean

    2016-01-01

    The purpose of this pretest-posttest control group experimental study was to see the effect of classroom walkthroughs on middle school teacher motivation. The independent variable was; classroom walkthroughs and the four dependent variables were teachers' self-concept of the ability to affect student achievement, teachers' attitude toward the…

  1. The Effects of Problem-Based Learning (PBL) on the Academic Achievement of Students Studying "Electrochemistry"

    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…

  2. Embedded Blended Learning within an Algebra Classroom: A Multimedia Capture Experiment

    ERIC Educational Resources Information Center

    Smith, J. G.; Suzuki, S.

    2015-01-01

    This two-group, pretest-posttest, quasi-experimental study compared secondary students' learning of Algebra II materials over a 4-week period when identical instruction by the same teacher was delivered through either embedded blended learning (treatment group; n?=?32) or a live-lecture classroom (control group; n?=?24). For both groups,…

  3. Performance, Cognitive Load, and Behaviour of Technology-Assisted English Listening Learning: From CALL to MALL

    ERIC Educational Resources Information Center

    Chang, Chi-Cheng; Warden, Clyde A.; Liang, Chaoyun; Chou, Pao-Nan

    2018-01-01

    This study examines differences in English listening comprehension, cognitive load, and learning behaviour between outdoor ubiquitous learning and indoor computer-assisted learning. An experimental design, employing a pretest-posttest control group is employed. Randomly assigned foreign language university majors joined either the experimental…

  4. An Analysis of the Mother and Child Education Program's Effects on the Relationship between Mothers and Their Five- or Six-Year-Old Children

    ERIC Educational Resources Information Center

    Ulutas, Aysegul; Kanak, Mehmet

    2016-01-01

    This study aims to analyze the effect of the Mother and Child Education Program on the relationship between mothers and their five- or six-year-old children. The study used an experimental design of pretest-posttest-monitoring test with a control group. The participants consisted of 50 preschool children aged five or six along with their mothers.…

  5. Tangent to Experimental Techniques of Verbal Control.

    ERIC Educational Resources Information Center

    Bilodeau, Ina McD.

    This paper is a critical comment and reaction to a 1965 article by G. A. Miller entitled "Some Preliminaries to Psycholinguistics." The subject matter is verbal control of behavior. Seven specific aspects of the Miller address are discussed. (WD)

  6. The Perils of Ignoring Design Effects in Experimental Studies: Lessons from a Mammography Screening Trial

    PubMed Central

    Glenn, Beth A.; Bastani, Roshan; Maxwell, Annette E.

    2013-01-01

    Objective Threats to external validity including pretest sensitization and the interaction of selection and an intervention are frequently overlooked by researchers despite their potential to significantly influence study outcomes. The purpose of this investigation was to conduct secondary data analyses to assess the presence of external validity threats in the setting of a randomized trial designed to promote mammography use in a high risk sample of women. Design During the trial, recruitment and intervention implementation took place in three cohorts (with different ethnic composition), utilizing two different designs (pretest-posttest control group design; posttest only control group design). Results Results reveal that the intervention produced different outcomes across cohorts, dependent upon the research design used and the characteristics of the sample. Conclusion These results illustrate the importance of weighing the pros and cons of potential research designs before making a selection and attending more closely to issues of external validity. PMID:23289517

  7. The perils of ignoring design effects in experimental studies: lessons from a mammography screening trial.

    PubMed

    Glenn, Beth A; Bastani, Roshan; Maxwell, Annette E

    2013-01-01

    Threats to external validity, including pretest sensitisation and the interaction of selection and an intervention, are frequently overlooked by researchers despite their potential to significantly influence study outcomes. The purpose of this investigation was to conduct secondary data analyses to assess the presence of external validity threats in the setting of a randomised trial designed to promote mammography use in a high-risk sample of women. During the trial, recruitment and intervention, implementation took place in three cohorts (with different ethnic composition), utilising two different designs (pretest-posttest control group design and posttest only control group design). Results reveal that the intervention produced different outcomes across cohorts, dependent upon the research design used and the characteristics of the sample. These results illustrate the importance of weighing the pros and cons of potential research designs before making a selection and attending more closely to issues of external validity.

  8. Experimental verification of Pyragas-Schöll-Fiedler control.

    PubMed

    von Loewenich, Clemens; Benner, Hartmut; Just, Wolfram

    2010-09-01

    We present an experimental realization of time-delayed feedback control proposed by Schöll and Fiedler. The scheme enables us to stabilize torsion-free periodic orbits in autonomous systems, and to overcome the so-called odd number limitation. The experimental control performance is in quantitative agreement with the bifurcation analysis of simple model systems. The results uncover some general features of the control scheme which are deemed to be relevant for a large class of setups.

  9. Experimental Flight Characterization of a Canard-Controlled, Subsonic Missile

    DTIC Science & Technology

    2017-08-01

    ARL-TR-8086 ● AUG 2017 US Army Research Laboratory Experimental Flight Characterization of a Canard- Controlled , Subsonic Missile...Laboratory Experimental Flight Characterization of a Canard- Controlled , Subsonic Missile by Frank Fresconi, Ilmars Celmins, James Maley, and...valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 1. REPORT DATE (DD-MM-YYYY) August 2017 2. REPORT TYPE Technical

  10. Multivariate dynamic linear models for estimating the effect of experimental interventions in an evolutionary operations setup in dairy herds.

    PubMed

    Stygar, Anna Helena; Krogh, Mogens Agerbo; Kristensen, Troels; Østergaard, Søren; Kristensen, Anders Ringgaard

    2017-07-01

    Evolutionary operations is a method to exploit the association of often small changes in process variables, planned during systematic experimentation and occurring during the normal production flow, to production characteristics to find a way to alter the production process to be more efficient. The objective of this study was to construct a tool to assess the intervention effect on milk production in an evolutionary operations setup. The method used for this purpose was a dynamic linear model (DLM) with Kalman filtering. The DLM consisted of parameters describing milk yield in a herd, individual cows from a herd, and an intervention effect on a given day. The model was constructed to handle any number of cows, experimental interventions, different data sources, or presence of control groups. In this study, data from 2 commercial Danish herds were used. In herd 1, data on 98,046 and 12,133 milkings registered from an automatic milking system (AMS) were used for model building and testing, respectively. In herd 2, data on 3,689 milkings on test days were used for estimating the initial model parameters. For model testing, data from both bulk tank milk yield (85 observations) and test-day milkings (1,471) were used. In herd 1, the manager wanted to explore the possibility of reducing the amount of concentrate provided to the cows in an AMS. In herd 2, the manager wanted to know if the milk yield could be increased by elevating the energy level provided to the cows in a total mixed ration. The experiment conducted in herd 1 was designed with a treatment and a control group, whereas in herd 2 we used a pretest/posttest design. The constructed tool provided estimates (mean and confidence intervals) for each of 3 interventions carried out in both herds. In herd 1, we concluded that the reduction in concentrate amount provided in the AMS had no negative influence on milk yield. For herd 2, the increased level of energy had a significant positive effect on milk yield but

  11. Experimental demonstration of the control of flexible structures

    NASA Technical Reports Server (NTRS)

    Schaechter, D. B.; Eldred, D. B.

    1984-01-01

    The Large Space Structure Technology Flexible Beam Experiment employs a pinned-free flexible beam to demonstrate such required methods as dynamic and adaptive control, as well as various control law design approaches and hardware requirements. An attempt is made to define the mechanization difficulties that may inhere in flexible structures. Attention is presently given to analytical work performed in support of the test facility's development, the final design's specifications, the control laws' synthesis, and experimental results obtained.

  12. Adaptive neural network motion control of manipulators with experimental evaluations.

    PubMed

    Puga-Guzmán, S; Moreno-Valenzuela, J; Santibáñez, V

    2014-01-01

    A nonlinear proportional-derivative controller plus adaptive neuronal network compensation is proposed. With the aim of estimating the desired torque, a two-layer neural network is used. Then, adaptation laws for the neural network weights are derived. Asymptotic convergence of the position and velocity tracking errors is proven, while the neural network weights are shown to be uniformly bounded. The proposed scheme has been experimentally validated in real time. These experimental evaluations were carried in two different mechanical systems: a horizontal two degrees-of-freedom robot and a vertical one degree-of-freedom arm which is affected by the gravitational force. In each one of the two experimental set-ups, the proposed scheme was implemented without and with adaptive neural network compensation. Experimental results confirmed the tracking accuracy of the proposed adaptive neural network-based controller.

  13. Adaptive Neural Network Motion Control of Manipulators with Experimental Evaluations

    PubMed Central

    Puga-Guzmán, S.; Moreno-Valenzuela, J.; Santibáñez, V.

    2014-01-01

    A nonlinear proportional-derivative controller plus adaptive neuronal network compensation is proposed. With the aim of estimating the desired torque, a two-layer neural network is used. Then, adaptation laws for the neural network weights are derived. Asymptotic convergence of the position and velocity tracking errors is proven, while the neural network weights are shown to be uniformly bounded. The proposed scheme has been experimentally validated in real time. These experimental evaluations were carried in two different mechanical systems: a horizontal two degrees-of-freedom robot and a vertical one degree-of-freedom arm which is affected by the gravitational force. In each one of the two experimental set-ups, the proposed scheme was implemented without and with adaptive neural network compensation. Experimental results confirmed the tracking accuracy of the proposed adaptive neural network-based controller. PMID:24574910

  14. Improving Science Achievement and Attitudes of Students With and Without Learning Disabilities

    NASA Astrophysics Data System (ADS)

    Sanders-White, Pamela

    The primary purpose of this study was to investigate the effect of structured note-taking compared to traditional note-taking on the acquisition of scientific knowledge for students with and without learning disabilities (LD) and students with reading difficulties (RD). An additional purpose was to examine whether the two note-taking methods affected students' attitudes toward science. The sample population consisted of 203 fifth grade students across four public schools in the southern area of the United States. A standardized instrument aligned to Florida's science standards was used to measure the acquisition of scientific knowledge and the Test of Science-Related Attitudes (TOSRA) was used to measure seven distinct science-related attitudes. For meaningful analyses, students with LD and students with RD were collapsed to form a single group due to the small numbers of participants in each of the subgroups; the collapsed group was referred to as "low achievers." A three-way repeated measures ANOVA was conducted to determine the effects of the pretest-posttest Science Interim assessment by group, type of student, and gender. The pretest-posttest Science Interim assessment scores were the within-group factor, while group, type of student, and gender were the between-groups factors. Results revealed that there was a significant interaction between the pretest-posttest Science Interim assessment and group, F(1, 191) = 9.320, p = .003, indicating that scientific knowledge scores increased for the experimental group, but decreased for the control group. Results also indicated that there was a significant three-way interaction between the pretest-posttest Science Interim assessment, group, and gender, F(1, 191) = 5.197, p = .024, showing that all participants in the experimental group improved their scores; while in the control group, female scores decreased and male scores increased. Participants in the experimental and control groups did not show improved attitudes

  15. Object impedance control for cooperative manipulation - Theory and experimental results

    NASA Technical Reports Server (NTRS)

    Schneider, Stanley A.; Cannon, Robert H., Jr.

    1992-01-01

    This paper presents the dynamic control module of the Dynamic and Strategic Control of Cooperating Manipulators (DASCCOM) project at Stanford University's Aerospace Robotics Laboratory. First, the cooperative manipulation problem is analyzed from a systems perspective, and the desirable features of a control system for cooperative manipulation are discussed. Next, a control policy is developed that enforces a controlled impedance not of the individual arm endpoints, but of the manipulated object itself. A parallel implementation for a multiprocessor system is presented. The controller fully compensates for the system dynamics and directly controls the object internal forces. Most importantly, it presents a simple, powerful, intuitive interface to higher level strategic control modules. Experimental results from a dual two-link-arm robotic system are used to compare the object impedance controller with other strategies, both for free-motion slews and environmental contact.

  16. Decentralized adaptive control of manipulators - Theory, simulation, and experimentation

    NASA Technical Reports Server (NTRS)

    Seraji, Homayoun

    1989-01-01

    The author presents a simple decentralized adaptive-control scheme for multijoint robot manipulators based on the independent joint control concept. The control objective is to achieve accurate tracking of desired joint trajectories. The proposed control scheme does not use the complex manipulator dynamic model, and each joint is controlled simply by a PID (proportional-integral-derivative) feedback controller and a position-velocity-acceleration feedforward controller, both with adjustable gains. Simulation results are given for a two-link direct-drive manipulator under adaptive independent joint control. The results illustrate trajectory tracking under coupled dynamics and varying payload. The proposed scheme is implemented on a MicroVAX II computer for motion control of the three major joints of a PUMA 560 arm. Experimental results are presented to demonstrate that trajectory tracking is achieved despite coupled nonlinear joint dynamics.

  17. Comparison of student self-debriefing versus instructor debriefing in nursing simulation: A quasi-experimental study.

    PubMed

    Kang, Kyungja; Yu, Mi

    2018-06-01

    Student self-debriefing promotes self-confidence, helps to increase clinical performance, and is a more cost-effective method than is traditional instructor-led debriefing in simulation-based learning. This study compared the effectiveness of debriefing-in terms of the problem-solving process, team effectiveness, debriefing assessment, and debriefing satisfaction-between an experimental group who received both student self-debriefing (SSD) and instructor debriefing (ID) and a control group who received only instructor debriefing. This quasi-experimental study used a pretest-posttest non-equivalent control group design. Two universities in South Korea. A convenience sample of 123 senior nursing students. The data were collected between 15 April and 9 June 2016. Differences in the problem-solving process, team effectiveness, debriefing assessment, and debriefing satisfaction between the SSD + ID group and the ID-only group were measured. The SSD + ID group showed significant improvements in the problem-solving process (t = 4.32, p < .001) and debriefing satisfaction (t = 3.19, p = .002), but not in debriefing assessment (t = 1.67, p = .097) or team effectiveness (t = 1.84, p = .069) compared to ID-only group. Specifically, as the number of student sessions increased, we observed significant differences in problem-solving ability (F = 9.44, p < .001), debriefing satisfaction (F = 7.78, p < .001), and the subdomains of debriefing assessment: 'maintains an engaging environment' (F = 3.78, p = .025), 'structures the debriefing in an organized way' (F = 4.27, p = .016), and 'helps trainees achieve or sustain future performance' (F = 3.17, p = .045). Our results can be used to develop guidelines for effective debriefing following simulation in nursing education. Specifically, combining SSD and ID in simulation debriefing and increasing the number of SSD sessions could help improve the problem

  18. A theoretical and experimental investigation of impact control for manipulators

    NASA Technical Reports Server (NTRS)

    Volpe, Richard; Khosla, Pradeep

    1993-01-01

    This article describes a simple control strategy for stable hardon-hard contact of a manipulator with the environment. The strategy is motivated by recognition of the equivalence of proportional gain explicit force control and impedance control. It is shown that negative proportional force gains, or impedance mass ratios less than unity, can equivalently provide excellent impact response without bouncing. This result is indicated by an analysis performed with an experimentally determined arm/sensor/environment model. The results are corroborated by experimental data from implementation of the control algorithms on the CMU DD Arm II system. The results confirm that manipulator impact against a stiff environment without bouncing can be readily handled by this novel control strategy.

  19. Identification and robust control of an experimental servo motor.

    PubMed

    Adam, E J; Guestrin, E D

    2002-04-01

    In this work, the design of a robust controller for an experimental laboratory-scale position control system based on a dc motor drive as well as the corresponding identification and robust stability analysis are presented. In order to carry out the robust design procedure, first, a classic closed-loop identification technique is applied and then, the parametrization by internal model control is used. The model uncertainty is evaluated under both parametric and global representation. For the latter case, an interesting discussion about the conservativeness of this description is presented by means of a comparison between the uncertainty disk and the critical perturbation radius approaches. Finally, conclusions about the performance of the experimental system with the robust controller are discussed using comparative graphics of the controlled variable and the Nyquist stability margin as a robustness measurement.

  20. Development and evaluation of a self care program on breastfeeding in Japan: A quasi-experimental study.

    PubMed

    Awano, Masayo; Shimada, Keiko

    2010-08-23

    Although the importance of breastfeeding is well known in Japan, in recent years less than 50% of mothers were fully breastfeeding at one month after birth. The purpose of this study was to develop a self-care program for breastfeeding aimed at increasing mothers' breastfeeding confidence and to evaluate its effectiveness. A quasi-experimental pretest-posttest design was conducted in Japan. The intervention, a breastfeeding self-care program, was created to improve mothers' self-efficacy for breastfeeding. This Breastfeeding Self-Care Program included: information on the advantages and basics of breastfeeding, a breastfeeding checklist to evaluate breastfeeding by mothers and midwives, and a pamphlet and audiovisual materials on breastfeeding. Mothers received this program during their postpartum hospital stay.A convenience sample of 117 primiparous women was recruited at two clinical sites from October 2007 to March 2008. The intervention group (n = 55), who gave birth in three odd-numbered months, received standard care and the Breastfeeding Self-Care Program while the control group (n = 62) gave birth in three even numbered months and received standard breastfeeding care.To evaluate the effectiveness of the Breastfeeding Self-Care Program, breastfeeding self-efficacy and breastfeeding rate were measured early postpartum, before the intervention, and after the intervention at one month postpartum. The study used the Japanese version of The Breastfeeding Self-Efficacy Scale Short Form (BSES-SF) to measure self-efficacy. The BSES-SF score of the intervention group rose significantly from 34.8 at early postpartum to 49.9 at one month after birth (p < 0.01). For the control group, the score rose from 39.5 at early postpartum to 46.5 at one month after birth (p = 0.03). The early postpartum fully breastfeeding rate was 90% for the intervention group and 89% for the control group. At one month postpartum, the fully breastfeeding rate declined significantly to 65% for

  1. Gut Microbiome Standardization in Control and Experimental Mice.

    PubMed

    McCoy, Kathy D; Geuking, Markus B; Ronchi, Francesca

    2017-04-03

    Mouse models are used extensively to study human health and to investigate the mechanisms underlying human disease. In the past, most animal studies were performed without taking into consideration the impact of the microbiota. However, the microbiota that colonizes all body surfaces, including the gastrointestinal tract, respiratory tract, genitourinary tract, and skin, heavily impacts nearly every aspect of host physiology. When performing studies utilizing mouse models it is critical to understand that the microbiome is heavily impacted by environmental factors, including (but not limited to) food, bedding, caging, and temperature. In addition, stochastic changes in the microbiota can occur over time that also play a role in shaping microbial composition. These factors lead to massive variability in the composition of the microbiota between animal facilities and research institutions, and even within a single facility. Lack of experimental reproducibility between research groups has highlighted the necessity for rigorously controlled experimental designs in order to standardize the microbiota between control and experimental animals. Well controlled experiments are mandatory in order to reduce variability and allow correct interpretation of experimental results, not just of host-microbiome studies but of all mouse models of human disease. The protocols presented are aimed to design experiments that control the microbiota composition between different genetic strains of experimental mice within an animal unit. © 2017 by John Wiley & Sons, Inc. Copyright © 2017 John Wiley & Sons, Inc.

  2. Experimental validation of flexible robot arm modeling and control

    NASA Technical Reports Server (NTRS)

    Ulsoy, A. Galip

    1989-01-01

    Flexibility is important for high speed, high precision operation of lightweight manipulators. Accurate dynamic modeling of flexible robot arms is needed. Previous work has mostly been based on linear elasticity with prescribed rigid body motions (i.e., no effect of flexible motion on rigid body motion). Little or no experimental validation of dynamic models for flexible arms is available. Experimental results are also limited for flexible arm control. Researchers include the effects of prismatic as well as revolute joints. They investigate the effect of full coupling between the rigid and flexible motions, and of axial shortening, and consider the control of flexible arms using only additional sensors.

  3. Second-order sliding mode control with experimental application.

    PubMed

    Eker, Ilyas

    2010-07-01

    In this article, a second-order sliding mode control (2-SMC) is proposed for second-order uncertain plants using equivalent control approach to improve the performance of control systems. A Proportional + Integral + Derivative (PID) sliding surface is used for the sliding mode. The sliding mode control law is derived using direct Lyapunov stability approach and asymptotic stability is proved theoretically. The performance of the closed-loop system is analysed through an experimental application to an electromechanical plant to show the feasibility and effectiveness of the proposed second-order sliding mode control and factors involved in the design. The second-order plant parameters are experimentally determined using input-output measured data. The results of the experimental application are presented to make a quantitative comparison with the traditional (first-order) sliding mode control (SMC) and PID control. It is demonstrated that the proposed 2-SMC system improves the performance of the closed-loop system with better tracking specifications in the case of external disturbances, better behavior of the output and faster convergence of the sliding surface while maintaining the stability. 2010 ISA. Published by Elsevier Ltd. All rights reserved.

  4. Remotely Piloted Vehicles for Experimental Flight Control Testing

    NASA Technical Reports Server (NTRS)

    Motter, Mark A.; High, James W.

    2009-01-01

    A successful flight test and training campaign of the NASA Flying Controls Testbed was conducted at Naval Outlying Field, Webster Field, MD during 2008. Both the prop and jet-powered versions of the subscale, remotely piloted testbeds were used to test representative experimental flight controllers. These testbeds were developed by the Subsonic Fixed Wing Project s emphasis on new flight test techniques. The Subsonic Fixed Wing Project is under the Fundamental Aeronautics Program of NASA's Aeronautics Research Mission Directorate (ARMD). The purpose of these testbeds is to quickly and inexpensively evaluate advanced concepts and experimental flight controls, with applications to adaptive control, system identification, novel control effectors, correlation of subscale flight tests with wind tunnel results, and autonomous operations. Flight tests and operator training were conducted during four separate series of tests during April, May, June and August 2008. Experimental controllers were engaged and disengaged during fully autonomous flight in the designated test area. Flaps and landing gear were deployed by commands from the ground control station as unanticipated disturbances. The flight tests were performed NASA personnel with support from the Maritime Unmanned Development and Operations (MUDO) team of the Naval Air Warfare Center, Aircraft Division

  5. Nonlinear feedback method of robot control - A preliminary experimental study

    NASA Technical Reports Server (NTRS)

    Tarn, T. J.; Ganguly, S.; Li, Z.; Bejczy, A. K.

    1990-01-01

    The nonlinear feedback method of robot control has been experimentally implemented on two PUMA 560 robot arms. The feasibility of the proposed controller, which was shown viable through simulation results earlier, is stressed. The servomechanism operates in task space, and the nonlinear feedback takes care of the necessary transformations to compute the necessary joint currents. A discussion is presented of the implementation with details of the experiments performed. The performance of the controller is encouraging but was limited to 100-Hz sampling frequency and to derived velocity information at the time of the experimentation. The setup of the lab, the software aspects, results, and the control hardware architecture that has recently been implemented are discussed.

  6. Experimental aeroelastic control using adaptive wing model concepts

    NASA Astrophysics Data System (ADS)

    Costa, Antonio P.; Moniz, Paulo A.; Suleman, Afzal

    2001-06-01

    The focus of this study is to evaluate the aeroelastic performance and control of adaptive wings. Ailerons and flaps have been designed and implemented into 3D wings for comparison with adaptive structures and active aerodynamic surface control methods. The adaptive structures concept, the experimental setup and the control design are presented. The wind-tunnel tests of the wing models are presented for the open- and closed-loop systems. The wind tunnel testing has allowed for quantifying the effectiveness of the piezoelectric vibration control of the wings, and also provided performance data for comparison with conventional aerodynamic control surfaces. The results indicate that a wing utilizing skins as active structural elements with embedded piezoelectric actuators can be effectively used to improve the aeroelastic response of aeronautical components. It was also observed that the control authority of adaptive wings is much greater than wings using conventional aerodynamic control surfaces.

  7. Experimental controlled-NOT gate simulation with thermal light

    PubMed Central

    Peng, Tao; Tamma, Vincenzo; Shih, Yanhua

    2016-01-01

    We report a recent experimental simulation of a controlled-NOT gate operation based on polarization correlation measurements of thermal fields in photon-number fluctuations. The interference between pairs of correlated paths at the very heart of these experiments has the potential for the simulation of correlations between a larger number of qubits. PMID:27439330

  8. Experimental Air Pressure Tank Systems for Process Control Education

    ERIC Educational Resources Information Center

    Long, Christopher E.; Holland, Charles E.; Gatzke, Edward P.

    2006-01-01

    In process control education, particularly in the field of chemical engineering, there is an inherent need for industrially relevant hands-on apparatuses that enable one to bridge the gap between the theoretical content of coursework and real-world applications. At the University of South Carolina, two experimental air-pressure tank systems have…

  9. A component analysis of biofeedback induced self-control of peripheral (finger) temperature.

    PubMed

    King, N J; Montgomery, R B

    1980-03-01

    Most of the research on biofeedback induced peripheral temperature control is open to serious methodological and theoretical criticisms. In the present research investigation, increase in peripheral (finger) temperature was targeted because of the possible therapeutic implications for the treatment of migraine and Raynaud's disease. Two experiments are reported in which the pretest-posttest control group design was employed to test the power of the variables in biofeedback induced self-control of finger temperature, and the necessity for subjects to engage in somatic manoeuvres. Significant increases in within-session and absolute finger temperature occurred in a test for self-control only for those subjects who had undergoing contingent feedback-somatic activity training conditions. It is suggested that future research should examine the role of mediational strategies in biofeedback-temperature training.

  10. Experimental Demonstration of Coherent Control in Quantum Chaotic Systems

    NASA Astrophysics Data System (ADS)

    Bitter, M.; Milner, V.

    2017-01-01

    We experimentally demonstrate coherent control of a quantum system, whose dynamics is chaotic in the classical limit. Interaction of diatomic molecules with a periodic sequence of ultrashort laser pulses leads to the dynamical localization of the molecular angular momentum, a characteristic feature of the chaotic quantum kicked rotor. By changing the phases of the rotational states in the initially prepared coherent wave packet, we control the rotational distribution of the final localized state and its total energy. We demonstrate the anticipated sensitivity of control to the exact parameters of the kicking field, as well as its disappearance in the classical regime of excitation.

  11. Hands-On Crops! How Long-Term Activities Improve Students' Knowledge of Crop Species. A Pretest-Posttest Study of the Greenhouse Project

    ERIC Educational Resources Information Center

    Fritsch, Eva-Maria; Lechner-Walz, Cornelia; Dreesmann, Daniel C.

    2015-01-01

    In terms of sustainability, renewable resources, nourishment and healthy diet, crops are important to the public. Thus, knowledge of crops is needed in order to enable people to participate in public discussions and take responsibility. This is in contrast to former surveys showing that students' knowledge of and interest in plants in general,…

  12. Differences in pain, function and coping in Multidimensional Pain Inventory subgroups of chronic back pain: a one-group pretest-posttest study.

    PubMed

    Verra, Martin L; Angst, Felix; Staal, J Bart; Brioschi, Roberto; Lehmann, Susanne; Aeschlimann, André; de Bie, Rob A

    2011-06-30

    Patients with non-specific back pain are not a homogeneous group but heterogeneous with regard to their bio-psycho-social impairments. This study examined a sample of 173 highly disabled patients with chronic back pain to find out how the three subgroups based on the Multidimensional Pain Inventory (MPI) differed in their response to an inpatient pain management program. Subgroup classification was conducted by cluster analysis using MPI subscale scores at entry into the program. At program entry and at discharge after four weeks, participants completed the MPI, the MOS Short Form-36 (SF-36), the Hospital Anxiety and Depression Scale (HADS), and the Coping Strategies Questionnaire (CSQ). Pairwise analyses of the score changes of the mentioned outcomes of the three MPI subgroups were performed using the Mann-Whitney-U-test for significance. Cluster analysis identified three MPI subgroups in this highly disabled sample: a dysfunctional, interpersonally distressed and an adaptive copers subgroup. The dysfunctional subgroup (29% of the sample) showed the highest level of depression in SF-36 mental health (33.4 ± 13.9), the interpersonally distressed subgroup (35% of the sample) a modest level of depression (46.8 ± 20.4), and the adaptive copers subgroup (32% of the sample) the lowest level of depression (57.8 ± 19.1). Significant differences in pain reduction and improvement of mental health and coping were observed across the three MPI subgroups, i.e. the effect sizes for MPI pain reduction were: 0.84 (0.44-1.24) for the dysfunctional subgroup, 1.22 (0.86-1.58) for the adaptive copers subgroup, and 0.53 (0.24-0.81) for the interpersonally distressed subgroup (p = 0.006 for pairwise comparison). Significant score changes between subgroups concerning activities and physical functioning could not be identified. MPI subgroup classification showed significant differences in score changes for pain, mental health and coping. These findings underscore the importance of assessing individual differences to understand how patients adjust to chronic back pain.

  13. Effects of the men's program on U.S. Army soldiers' intentions to commit and willingness to intervene to prevent rape: a pretest posttest study.

    PubMed

    Foubert, John D; Masin, Ryan C

    2012-01-01

    Noncommissioned male officers in the U.S. Army stationed in Germany were trained to present a 1-hour rape prevention workshop--The Men's Program--to 237 enlisted male soldiers. A comparison group of 244 male soldiers received a briefing focused on reducing the individual's risk for experiencing sexual assault, discussion of myths and facts about sexual assault, and how to avoid being accused of sexual assault. Participants in The Men's Program experienced significant change in the predicted direction for bystander willingness to help, bystander efficacy, rape myth acceptance, likelihood of raping, and likelihood of committing sexual assault with low to medium effect sizes. Comparison group participants experienced no effect on these variables except for a significant decline in rape myth acceptance with a very low effect size. Between-group differences pointed to the efficacy of The Men's Program. Implications of these results for rape prevention programming in the military are discussed.

  14. Evaluation of an Education and Training Program to Prevent and Manage Patients' Violence in a Mental Health Setting: A Pretest-Posttest Intervention Study.

    PubMed

    Guay, Stéphane; Goncalves, Jane; Boyer, Richard

    2016-08-01

    Workplace violence can lead to serious consequences for victims, organizations, and society. Most workplace violence prevention programs aim to train staff to better recognize and safely manage at-risk situations. The Omega education and training program was developed in Canada in 1999, and has since been used to teach healthcare and mental health workers the skills needed to effectively intervene in situations of aggression. The present study was designed to assess the impact of Omega on employee psychological distress, confidence in coping, and perceived exposure to violence. This program was offered to 105 employees in a psychiatric hospital in Montreal, Canada. Eighty-nine of them accepted to participate. Questionnaires were completed before the training, after a short period of time (M = 109 days) and at follow-up (M = 441 days). Repeated-measures ANOVAs and Cohen's d effect sizes were calculated. Results demonstrated statistically significant improvements in short-term and follow-up posttest scores of psychological distress, confidence in coping, and in levels of exposure to violence. This study is one of very few to demonstrate the positive impact of this training program. Further research is needed to understand how to improve the effectiveness of the program, especially among participants resistant to change.

  15. Benefit of pelvic floor muscle therapy in improving sexual function in women with stress urinary incontinence: a pretest-posttest intervention study.

    PubMed

    Serati, Maurizio; Braga, Andrea; Di Dedda, Maria Carmela; Sorice, Paola; Peano, Elena; Biroli, Antonella; Torella, Marco; Cromi, Antonella; Uccella, Stefano; Salvatore, Stefano; Ghezzi, Fabio

    2015-01-01

    Very few data are available on the effect of pelvic floor muscle training on sexual function in incontinent women. The authors used the Female Sexual Function Index to assess the effect of pelvic floor muscle training on female sexual function. Participants included women with stress urinary incontinence, without overactive bladder symptoms, who completed a 3-month pelvic floor muscle training. All patients completed the Female Sexual Function Index and the International Consultation on Incontinence Questionnaire-Short Form at baseline and at the 3-month follow-up. Thirty-four patients completed all of the questionnaires; 64.7% patients were referred with stress urinary incontinence without sexual disorders, while 35.3% complained of stress urinary incontinence and sexual symptoms. The International Consultation on Incontinence Questionnaire-Short Form score significantly decreased after 3 months of pelvic floor muscle training (p =.01). The Female Sexual Function Index score significantly improved after pelvic floor muscle training even in women with sexual disorders (12.5 ± 9.5 vs. 29.7 ± 3.7; p <.001). This study showed that pelvic floor muscle training may improve female sexual function in women with pure stress urinary incontinence.

  16. Evaluation of an Education and Training Program to Prevent and Manage Patients’ Violence in a Mental Health Setting: A Pretest-Posttest Intervention Study

    PubMed Central

    Guay, Stéphane; Goncalves, Jane; Boyer, Richard

    2016-01-01

    Workplace violence can lead to serious consequences for victims, organizations, and society. Most workplace violence prevention programs aim to train staff to better recognize and safely manage at-risk situations. The Omega education and training program was developed in Canada in 1999, and has since been used to teach healthcare and mental health workers the skills needed to effectively intervene in situations of aggression. The present study was designed to assess the impact of Omega on employee psychological distress, confidence in coping, and perceived exposure to violence. This program was offered to 105 employees in a psychiatric hospital in Montreal, Canada. Eighty-nine of them accepted to participate. Questionnaires were completed before the training, after a short period of time (M = 109 days) and at follow-up (M = 441 days). Repeated-measures ANOVAs and Cohen’s d effect sizes were calculated. Results demonstrated statistically significant improvements in short-term and follow-up posttest scores of psychological distress, confidence in coping, and in levels of exposure to violence. This study is one of very few to demonstrate the positive impact of this training program. Further research is needed to understand how to improve the effectiveness of the program, especially among participants resistant to change. PMID:27490582

  17. Experimental investigation of active loads control for aircraft landing gear

    NASA Technical Reports Server (NTRS)

    Mcgehee, J. R.; Dreher, R. C.

    1982-01-01

    Aircraft dynamic loads and vibrations resulting from landing impact and from runway and taxiway unevenness are recognized as significant in causing fatigue damage, dynamic stress on the airframe, crew and passenger discomfort, and reduction of the pilot's ability to control the aircraft during ground operations. One potential method for improving operational characteistics of aircraft on the ground is the application of active control technology to the landing gears to reduce ground loads applied to the airframe. An experimental investigation was conducted which simulated the landing dynamics of a light airplane to determine the feasibility and potential of a series hydraulic active control main landing gear. The experiments involved a passive gear and an active control gear. Results of this investigation show that a series hydraulically controlled gear is feasible and that such a gear is very effective in reducing the loads transmitted by the gear to the airframe during ground operations.

  18. Installation of automatic control at experimental breeder reactor II

    SciTech Connect

    Larson, H.A.; Booty, W.F.; Chick, D.R.

    1985-08-01

    The Experimental Breeder Reactor II (EBR-II) has been modified to permit automatic control capability. Necessary mechanical and electrical changes were made on a regular control rod position; motor, gears, and controller were replaced. A digital computer system was installed that has the programming capability for varied power profiles. The modifications permit transient testing at EBR-II. Experiments were run that increased power linearly as much as 4 MW/s (16% of initial power of 25 MW(thermal)/s), held power constant, and decreased power at a rate no slower than the increase rate. Thus the performance of the automatic control algorithm, the mechanical andmore » electrical control equipment, and the qualifications of the driver fuel for future power change experiments were all demonstrated.« less

  19. Effects of Video Game Training on Behavioral and Electrophysiological Measures of Attention and Memory: Protocol for a Randomized Controlled Trial

    PubMed Central

    Mayas, Julia; Ruiz-Marquez, Eloisa; Prieto, Antonio; Toril, Pilar; Ponce de Leon, Laura; de Ceballos, Maria L; Reales Avilés, José Manuel

    2017-01-01

    Background Neuroplasticity-based approaches seem to offer promising ways of maintaining cognitive health in older adults and postponing the onset of cognitive decline symptoms. Although previous research suggests that training can produce transfer effects, this study was designed to overcome some limitations of previous studies by incorporating an active control group and the assessment of training expectations. Objective The main objectives of this study are (1) to evaluate the effects of a randomized computer-based intervention consisting of training older adults with nonaction video games on brain and cognitive functions that decline with age, including attention and spatial working memory, using behavioral measures and electrophysiological recordings (event-related potentials [ERPs]) just after training and after a 6-month no-contact period; (2) to explore whether motivation, engagement, or expectations might account for possible training-related improvements; and (3) to examine whether inflammatory mechanisms assessed with noninvasive measurement of C-reactive protein in saliva impair cognitive training-induced effects. A better understanding of these mechanisms could elucidate pathways that could be targeted in the future by either behavioral or neuropsychological interventions. Methods A single-blinded randomized controlled trial with an experimental group and an active control group, pretest, posttest, and 6-month follow-up repeated measures design is used in this study. A total of 75 cognitively healthy older adults were randomly distributed into experimental and active control groups. Participants in the experimental group received 16 1-hour training sessions with cognitive nonaction video games selected from Lumosity, a commercial brain training package. The active control group received the same number of training sessions with The Sims and SimCity, a simulation strategy game. Results We have recruited participants, have conducted the training protocol

  20. A PARENT–ADOLESCENT INTERVENTION TO INCREASE SEXUAL RISK COMMUNICATION: RESULTS OF A RANDOMIZED CONTROLLED TRIAL

    PubMed Central

    Villarruel, Antonia M.; Cherry, Carol Loveland; Cabriales, Esther Gallegos; Ronis, David L.; Zhou, Yan

    2009-01-01

    This article reports results of a randomized controlled trial designed to test an intervention to increase parent–adolescent sexual risk communication among Mexican parents. Data were analyzed from parents (n = 791) randomly assigned to an HTV risk reduction or health promotion intervention. Measures were administered at pretest, posttest, and 6– and 12–month follow–ups. Generalized estimation equation (GEE) analysis indicates parents in the HIV risk reduction intervention reported significantly more general communication (p < .005), more sexual risk communication (p < .001) and more comfort with communication (p < .001) than parents in the control intervention. Behavioral, normative, and control beliefs significantly mediated the effect of the intervention on all communication outcomes. This study demonstrates the efficacy of an intervention to increase the quality and quantity of parent–adolescent communication related to general and sex–specific communication. PMID:18956979

  1. The effects of overhead transparency design on retention, recall, and application of data analysis content.

    PubMed

    Van Hoozer, H; Brink, P J; Oppliger, R

    1989-04-01

    This experimental study tested the effects of overhead transparency design in conjunction with live lecture on retention, recall, and application of data analysis content over three occasions using a Solomon Four-Group, pretest-posttest design. Pretested subjects showed significant (p less than .001) gains in test scores from pre to posttest. No significant differences were found in pretest scores between control and experimental treatment groups or among the posttest scores of either the experimental or control groups.

  2. Experimental demonstration of active vibration control for flexible structures

    NASA Technical Reports Server (NTRS)

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

    1990-01-01

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

  3. Perceptions vs Reality: A Longitudinal Experiment in Influenced Judgement Performance

    DTIC Science & Technology

    2003-03-25

    validity were manifested equally between treatment and control groups , thereby lending further validity to the experimental research design . External...Stanley (1975) identify this as a True Experimental Design : Pretest- Posttest Control Group Design . However, due to the longitudinal aspect required to...1975:43). Nonequivalence will be ruled out as pretest equivalence is shown between treatment and control groups (1975:47). For quasi

  4. Experimental Validation of a Resilient Monitoring and Control System

    SciTech Connect

    Wen-Chiao Lin; Kris R. E. Villez; Humberto E. Garcia

    2014-05-01

    Complex, high performance, engineering systems have to be closely monitored and controlled to ensure safe operation and protect public from potential hazards. One of the main challenges in designing monitoring and control algorithms for these systems is that sensors and actuators may be malfunctioning due to malicious or natural causes. To address this challenge, this paper addresses a resilient monitoring and control (ReMAC) system by expanding previously developed resilient condition assessment monitoring systems and Kalman filter-based diagnostic methods and integrating them with a supervisory controller developed here. While the monitoring and diagnostic algorithms assess plant cyber and physical health conditions,more » the supervisory controller selects, from a set of candidates, the best controller based on the current plant health assessments. To experimentally demonstrate its enhanced performance, the developed ReMAC system is then used for monitoring and control of a chemical reactor with a water cooling system in a hardware-in-the-loop setting, where the reactor is computer simulated and the water cooling system is implemented by a machine condition monitoring testbed at Idaho National Laboratory. Results show that the ReMAC system is able to make correct plant health assessments despite sensor malfunctioning due to cyber attacks and make decisions that achieve best control actions despite possible actuator malfunctioning. Monitoring challenges caused by mismatches between assumed system component models and actual measurements are also identified for future work.« less

  5. Experimental determination of group flux control coefficients in metabolic networks

    SciTech Connect

    Simpson, T.W.; Shimizu, Hiroshi; Stephanopoulos, G.

    1998-04-20

    Grouping of reactions around key metabolite branch points can facilitate the study of metabolic control of complex metabolic networks. This top-down Metabolic Control Analysis is exemplified through the introduction of group control coefficients whose magnitudes provide a measure of the relative impact of each reaction group on the overall network flux, as well as on the overall network stability, following enzymatic amplification. In this article, the authors demonstrate the application of previously developed theory to the determination of group flux control coefficients. Experimental data for the changes in metabolic fluxes obtained in response to the introduction of six different environmentalmore » perturbations are used to determine the group flux control coefficients for three reaction groups formed around the phosphoenolpyruvate/pyruvate branch point. The consistency of the obtained group flux control coefficient estimates is systematically analyzed to ensure that all necessary conditions are satisfied. The magnitudes of the determined control coefficients suggest that the control of lysine production flux in Corynebacterium glutamicum cells at a growth base state resides within the lysine biosynthetic pathway that begins with the PEP/PYR carboxylation anaplorotic pathway.« less

  6. Construction of a WMR for trajectory tracking control: experimental results.

    PubMed

    Silva-Ortigoza, R; Márquez-Sánchez, C; Marcelino-Aranda, M; Marciano-Melchor, M; Silva-Ortigoza, G; Bautista-Quintero, R; Ramos-Silvestre, E R; Rivera-Díaz, J C; Muñoz-Carrillo, D

    2013-01-01

    This paper reports a solution for trajectory tracking control of a differential drive wheeled mobile robot (WMR) based on a hierarchical approach. The general design and construction of the WMR are described. The hierarchical controller proposed has two components: a high-level control and a low-level control. The high-level control law is based on an input-output linearization scheme for the robot kinematic model, which provides the desired angular velocity profiles that the WMR has to track in order to achieve the desired position (x∗, y∗) and orientation (φ∗). Then, a low-level control law, based on a proportional integral (PI) approach, is designed to control the velocity of the WMR wheels to ensure those tracking features. Regarding the trajectories, this paper provides the solution or the following cases: (1) time-varying parametric trajectories such as straight lines and parabolas and (2) smooth curves fitted by cubic splines which are generated by the desired data points {(x₁∗, y₁∗),..., (x(n)∗, y(n)∗)}. A straightforward algorithm is developed for constructing the cubic splines. Finally, this paper includes an experimental validation of the proposed technique by employing a DS1104 dSPACE electronic board along with MATLAB/Simulink software.

  7. Construction of a WMR for Trajectory Tracking Control: Experimental Results

    PubMed Central

    Silva-Ortigoza, R.; Márquez-Sánchez, C.; Marcelino-Aranda, M.; Marciano-Melchor, M.; Silva-Ortigoza, G.; Bautista-Quintero, R.; Ramos-Silvestre, E. R.; Rivera-Díaz, J. C.; Muñoz-Carrillo, D.

    2013-01-01

    This paper reports a solution for trajectory tracking control of a differential drive wheeled mobile robot (WMR) based on a hierarchical approach. The general design and construction of the WMR are described. The hierarchical controller proposed has two components: a high-level control and a low-level control. The high-level control law is based on an input-output linearization scheme for the robot kinematic model, which provides the desired angular velocity profiles that the WMR has to track in order to achieve the desired position (x∗, y∗) and orientation (φ∗). Then, a low-level control law, based on a proportional integral (PI) approach, is designed to control the velocity of the WMR wheels to ensure those tracking features. Regarding the trajectories, this paper provides the solution or the following cases: (1) time-varying parametric trajectories such as straight lines and parabolas and (2) smooth curves fitted by cubic splines which are generated by the desired data points {(x1∗, y1∗),..., (xn∗, yn∗)}. A straightforward algorithm is developed for constructing the cubic splines. Finally, this paper includes an experimental validation of the proposed technique by employing a DS1104 dSPACE electronic board along with MATLAB/Simulink software. PMID:23997679

  8. Experimental investigation of jet pulse control on flexible vibrating structures

    NASA Astrophysics Data System (ADS)

    Karaiskos, Grigorios; Papanicolaou, Panos; Zacharopoulos, Dimitrios

    2016-08-01

    The feasibility of applying on-line fluid jet pulses to actively control the vibrations of flexible structures subjected to harmonic and earthquake-like base excitations provided by a shake table is explored. The operating principles and capabilities of the control system applied have been investigated in a simplified small-scale laboratory model that is a mass attached at the top free end of a vertical flexible slender beam with rectangular cross-section, the other end of which is mounted on an electrodynamic shaker. A pair of opposite jets placed on the mass at the top of the cantilever beam applied the appropriate forces by ejecting pressurized air pulses controlled by on/off solenoid electro-valves via in house developed control software, in order to control the vibration caused by harmonic, periodic and random excitations at pre-selected frequency content provided by the shaker. The dynamics of the structure was monitored by accelerometers and the jet impulses by pressure sensors. The experimental results have demonstrated the effectiveness and reliability of Jet Pulse Control Systems (JPCS). It was verified that the measured root mean square (RMS) vibration levels of the controlled structure from harmonic and earthquake base excitations, could be reduced by approximately 50% and 33% respectively.

  9. Efficacy of Adolescent Suicide Prevention E-Learning Modules for Gatekeepers: A Randomized Controlled Trial.

    PubMed

    Ghoncheh, Rezvan; Gould, Madelyn S; Twisk, Jos Wr; Kerkhof, Ad Jfm; Koot, Hans M

    2016-01-29

    Face-to-face gatekeeper training can be an effective strategy in the enhancement of gatekeepers' knowledge and self-efficacy in adolescent suicide prevention. However, barriers related to access (eg, time, resources) may hamper participation in face-to-face training sessions. The transition to a Web-based setting could address obstacles associated with face-to-face gatekeeper training. Although Web-based suicide prevention training targeting adolescents exists, so far no randomized controlled trials (RCTs) have been conducted to investigate their efficacy. This RCT study investigated the efficacy of a Web-based adolescent suicide prevention program entitled Mental Health Online, which aimed to improve the knowledge and self-confidence of gatekeepers working with adolescents (12-20 years old). The program consisted of 8 short e-learning modules each capturing an important aspect of the process of early recognition, guidance, and referral of suicidal adolescents, alongside additional information on the topic of (adolescent) suicide prevention. A total of 190 gatekeepers (ages 21 to 62 years) participated in this study and were randomized to either the experimental group or waitlist control group. The intervention was not masked. Participants from both groups completed 3 Web-based assessments (pretest, posttest, and 3-month follow-up). The outcome measures of this study were actual knowledge, and participants' ratings of perceived knowledge and perceived self-confidence using questionnaires developed specifically for this study. The actual knowledge, perceived knowledge, and perceived self-confidence of gatekeepers in the experimental group improved significantly compared to those in the waitlist control group at posttest, and the effects remained significant at 3-month follow-up. The overall effect sizes were 0.76, 1.20, and 1.02, respectively, across assessments. The findings of this study indicate that Web-based suicide prevention e-learning modules can be an

  10. Efficacy of Adolescent Suicide Prevention E-Learning Modules for Gatekeepers: A Randomized Controlled Trial

    PubMed Central

    Gould, Madelyn S; Twisk, Jos WR; Kerkhof, Ad JFM; Koot, Hans M

    2016-01-01

    Background Face-to-face gatekeeper training can be an effective strategy in the enhancement of gatekeepers’ knowledge and self-efficacy in adolescent suicide prevention. However, barriers related to access (eg, time, resources) may hamper participation in face-to-face training sessions. The transition to a Web-based setting could address obstacles associated with face-to-face gatekeeper training. Although Web-based suicide prevention training targeting adolescents exists, so far no randomized controlled trials (RCTs) have been conducted to investigate their efficacy. Objective This RCT study investigated the efficacy of a Web-based adolescent suicide prevention program entitled Mental Health Online, which aimed to improve the knowledge and self-confidence of gatekeepers working with adolescents (12-20 years old). The program consisted of 8 short e-learning modules each capturing an important aspect of the process of early recognition, guidance, and referral of suicidal adolescents, alongside additional information on the topic of (adolescent) suicide prevention. Methods A total of 190 gatekeepers (ages 21 to 62 years) participated in this study and were randomized to either the experimental group or waitlist control group. The intervention was not masked. Participants from both groups completed 3 Web-based assessments (pretest, posttest, and 3-month follow-up). The outcome measures of this study were actual knowledge, and participants’ ratings of perceived knowledge and perceived self-confidence using questionnaires developed specifically for this study. Results The actual knowledge, perceived knowledge, and perceived self-confidence of gatekeepers in the experimental group improved significantly compared to those in the waitlist control group at posttest, and the effects remained significant at 3-month follow-up. The overall effect sizes were 0.76, 1.20, and 1.02, respectively, across assessments. Conclusions The findings of this study indicate that Web

  11. Counter-Attrition Programs in the United States Armed Forces

    DTIC Science & Technology

    1984-07-01

    the average pretest - posttest improvement of ART students on the Gates-MacGinitie Reading Test was 2.5 RGL. No comparison control group change scores...retraining programs, elaborate quasi - experimentation could be readily built Into the existing operational system. Every major installation has one or more...research on teach-n. Chicago: Rand McNally, 1963, pp. 171-246. Reprinted as Experimental and quasi - experimental designs for research. Chicago: Rand

  12. Analytical and experimental study of control effort associated with model reference adaptive control

    NASA Technical Reports Server (NTRS)

    Messer, R. S.; Haftka, R. T.; Cudney, H. H.

    1992-01-01

    Numerical simulation results presently obtained for the performance of model reference adaptive control (MRAC) are experimentally verified, with a view to accounting for differences between the plant and the reference model after the control function has been brought to bear. MRAC is both experimentally and analytically applied to a single-degree-of-freedom system, as well as analytically to a MIMO system having controlled differences between the reference model and the plant. The control effort is noted to be sensitive to differences between the plant and the reference model.

  13. Experimental control of a fluidic pinball using genetic programming

    NASA Astrophysics Data System (ADS)

    Raibaudo, Cedric; Zhong, Peng; Noack, Bernd R.; Martinuzzi, Robert J.

    2017-11-01

    The wake stabilization of a triangular cluster of three rotating cylinders was investigated in the present study. Experiments were performed at Reynolds number Re 6000, and compared with URANS-2D simulations at same flow conditions. 2D2C PIV measurements and constant temperature anemometry were used to characterize the flow without and with actuation. Open-loop actuation was first considered for the identification of particular control strategies. Machine learning control was also implemented for the experimental study. Linear genetic programming has been used for the optimization of open-loop parameters and closed-loop controllers. Considering a cost function J based on the fluctuations of the velocity measured by the hot-wire sensor, significant performances were achieved using the machine learning approach. The present work is supported by the senior author's (R. J. Martinuzzi) NSERC discovery Grant. C. Raibaudo acknowledges the financial support of the University of Calgary Eyes-High PDF program.

  14. Feedback control in deep drawing based on experimental datasets

    NASA Astrophysics Data System (ADS)

    Fischer, P.; Heingärtner, J.; Aichholzer, W.; Hortig, D.; Hora, P.

    2017-09-01

    In large-scale production of deep drawing parts, like in automotive industry, the effects of scattering material properties as well as warming of the tools have a significant impact on the drawing result. In the scope of the work, an approach is presented to minimize the influence of these effects on part quality by optically measuring the draw-in of each part and adjusting the settings of the press to keep the strain distribution, which is represented by the draw-in, inside a certain limit. For the design of the control algorithm, a design of experiments for in-line tests is used to quantify the influence of the blank holder force as well as the force distribution on the draw-in. The results of this experimental dataset are used to model the process behavior. Based on this model, a feedback control loop is designed. Finally, the performance of the control algorithm is validated in the production line.

  15. Experimental comparison of PV-smoothing controllers using distributed generators

    SciTech Connect

    Johnson, Jay Dean; Ellis, Abraham; Denda, Atsushi

    The power output variability of photovoltaic systems can affect local electrical grids in locations with high renewable energy penetrations or weak distribution or transmission systems. In those rare cases, quick controllable generators (e.g., energy storage systems) or loads can counteract the destabilizing effects by compensating for the power fluctuations. Previously, control algorithms for coordinated and uncoordinated operation of a small natural gas engine-generator (genset) and a battery for smoothing PV plant output were optimized using MATLAB/Simulink simulations. The simulations demonstrated that a traditional generation resource such as a natural gas genset in combination with a battery would smooth the photovoltaicmore » output while using a smaller battery state of charge (SOC) range and extending the life of the battery. This paper reports on the experimental implementation of the coordinated and uncoordinated controllers to verify the simulations and determine the differences in the controllers. The experiments were performed with the PNM PV and energy storage Prosperity site and a gas engine-generator located at the Aperture Center at Mesa Del Sol in Albuquerque, New Mexico. Two field demonstrations were performed to compare the different PV smoothing control algorithms: (1) implementing the coordinated and uncoordinated controls while switching off a subsection of the PV array at precise times on successive clear days, and (2) comparing the results of the battery and genset outputs for the coordinated control on a high variability day with simulations of the coordinated and uncoordinated controls. It was found that for certain PV power profiles the SOC range of the battery may be larger with the coordinated control, but the total amp-hours through the battery-which approximates battery wear-will always be smaller with the coordinated control.« less

  16. Flexible distributed architecture for semiconductor process control and experimentation

    NASA Astrophysics Data System (ADS)

    Gower, Aaron E.; Boning, Duane S.; McIlrath, Michael B.

    1997-01-01

    Semiconductor fabrication requires an increasingly expensive and integrated set of tightly controlled processes, driving the need for a fabrication facility with fully computerized, networked processing equipment. We describe an integrated, open system architecture enabling distributed experimentation and process control for plasma etching. The system was developed at MIT's Microsystems Technology Laboratories and employs in-situ CCD interferometry based analysis in the sensor-feedback control of an Applied Materials Precision 5000 Plasma Etcher (AME5000). Our system supports accelerated, advanced research involving feedback control algorithms, and includes a distributed interface that utilizes the internet to make these fabrication capabilities available to remote users. The system architecture is both distributed and modular: specific implementation of any one task does not restrict the implementation of another. The low level architectural components include a host controller that communicates with the AME5000 equipment via SECS-II, and a host controller for the acquisition and analysis of the CCD sensor images. A cell controller (CC) manages communications between these equipment and sensor controllers. The CC is also responsible for process control decisions; algorithmic controllers may be integrated locally or via remote communications. Finally, a system server images connections from internet/intranet (web) based clients and uses a direct link with the CC to access the system. Each component communicates via a predefined set of TCP/IP socket based messages. This flexible architecture makes integration easier and more robust, and enables separate software components to run on the same or different computers independent of hardware or software platform.

  17. Active Flow Control: Instrumentation Automation and Experimental Technique

    NASA Technical Reports Server (NTRS)

    Gimbert, N. Wes

    1995-01-01

    In investigating the potential of a new actuator for use in an active flow control system, several objectives had to be accomplished, the largest of which was the experimental setup. The work was conducted at the NASA Langley 20x28 Shear Flow Control Tunnel. The actuator named Thunder, is a high deflection piezo device recently developed at Langley Research Center. This research involved setting up the instrumentation, the lighting, the smoke, and the recording devices. The instrumentation was automated by means of a Power Macintosh running LabVIEW, a graphical instrumentation package developed by National Instruments. Routines were written to allow the tunnel conditions to be determined at a given instant at the push of a button. This included determination of tunnel pressures, speed, density, temperature, and viscosity. Other aspects of the experimental equipment included the set up of a CCD video camera with a video frame grabber, monitor, and VCR to capture the motion. A strobe light was used to highlight the smoke that was used to visualize the flow. Additional effort was put into creating a scale drawing of another tunnel on site and a limited literature search in the area of active flow control.

  18. Experimental teleportation of a quantum controlled-NOT gate.

    PubMed

    Huang, Yun-Feng; Ren, Xi-Feng; Zhang, Yong-Sheng; Duan, Lu-Ming; Guo, Guang-Can

    2004-12-10

    Teleportation of quantum gates is a critical step for the implementation of quantum networking and teleportation-based models of quantum computation. We report an experimental demonstration of teleportation of the prototypical quantum controlled-NOT (CNOT) gate. Assisted with linear optical manipulations, photon entanglement produced from parametric down-conversion, and postselection from the coincidence measurements, we teleport the quantum CNOT gate from acting on local qubits to acting on remote qubits. The quality of the quantum gate teleportation is characterized through the method of quantum process tomography, with an average fidelity of 0.84 demonstrated for the teleported gate.

  19. The effects of computer-assisted instruction and locus of control upon preservice elementary teachers' acquisition of the integrated science process skills

    NASA Astrophysics Data System (ADS)

    Wesley, Beth Eddinger; Krockover, Gerald H.; Devito, Alfred

    The purpose of this study was to determine the effects of computer-assisted instruction (CAI) versus a text mode of programmed instruction (PI), and the cognitive style of locus of control, on preservice elementary teachers' achievement of the integrated science process skills. Eighty-one preservice elementary teachers in six sections of a science methods class were classified as internally or externally controlled. The sections were randomly assigned to receive instruction in the integrated science process skills via a microcomputer or printed text. The study used a pretest-posttest control group design. Before assessing main and interaction effects, analysis of covariance was used to adjust posttest scores using the pretest scores. Statistical analysis revealed that main effects were not significant. Additionally, no interaction effects between treatments and loci of control were demonstrated. The results suggest that printed PI and tutorial CAI are equally effective modes of instruction for teaching internally and externally oriented preservice elementary teachers the integrated science process skills.

  20. Surgical smoke control with local exhaust ventilation: Experimental study.

    PubMed

    Lee, Taekhee; Soo, Jhy-Charm; LeBouf, Ryan F; Burns, Dru; Schwegler-Berry, Diane; Kashon, Michael; Bowers, Jay; Harper, Martin

    2018-04-01

    This experimental study aimed to evaluate airborne particulates and volatile organic compounds (VOCs) from surgical smoke when a local exhaust ventilation (LEV) system is in place. Surgical smoke was generated from human tissue in an unoccupied operating room using an electrocautery surgical device for 15 min with 3 different test settings: (1) without LEV control; (2) control with a wall irrigation suction unit with an in-line ultra-low penetration air filter; and (3) control with a smoke evacuation system. Flow rate of LEVs was approximately 35 L/min and suction was maintained within 5 cm of electrocautery interaction site. A total of 6 experiments were conducted. Particle number and mass concentrations were measured using direct reading instruments including a condensation particle counter (CPC), a light-scattering laser photometer (DustTrak DRX), a scanning mobility particle sizer (SMPS), an aerodynamic particle sizer (APS), and a viable particle counter. Selected VOCs were collected using evacuated canisters using grab, personal and area sampling techniques. The largest average particle and VOCs concentrations were found in the absence of LEV control followed by LEV controls. Average ratios of LEV controls to without LEV control ranged 0.24-0.33 (CPC), 0.28-0.39 (SMPS), 0.14-0.31 (DustTrak DRX), and 0.26-0.55 (APS). Ethanol and isopropyl alcohol were dominant in the canister samples. Acetaldehyde, acetone, acetonitrile, benzene, hexane, styrene, and toluene were detected but at lower concentrations (<500 μg/m 3 ) and concentrations of the VOCs were much less than the National Institute for Occupational Safety and Health recommended exposure limit values. Utilization of the LEVs for surgical smoke control can significantly reduce but not completely eliminate airborne particles and VOCs.

  1. Experimental effective shape control of a powered transfemoral prosthesis.

    PubMed

    Gregg, Robert D; Lenzi, Tommaso; Fey, Nicholas P; Hargrove, Levi J; Sensinger, Jonathon W

    2013-06-01

    This paper presents the design and experimental implementation of a novel feedback control strategy that regulates effective shape on a powered transfemoral prosthesis. The human effective shape is the effective geometry to which the biological leg conforms--through movement of ground reaction forces and leg joints--during the stance period of gait. Able-bodied humans regulate effective shapes to be invariant across conditions such as heel height, walking speed, and body weight, so this measure has proven to be a very useful tool for the alignment and design of passive prostheses. However, leg joints must be actively controlled to assume different effective shapes that are unique to tasks such as standing, walking, and stair climbing. Using our previous simulation studies as a starting point, we model and control the effective shape as a virtual kinematic constraint on the powered Vanderbilt prosthetic leg with a custom instrumented foot. An able-bodied subject used a by-pass adapter to walk on the controlled leg over ground and over a treadmill. These preliminary experiments demonstrate, for the first time, that effective shape (or virtual constraints in general) can be used to control a powered prosthetic leg.

  2. Experimental robot gripper control for handling of soft objects

    NASA Astrophysics Data System (ADS)

    Friedrich, Werner E.; Ziegler, T. H.; Lim, P.

    1996-10-01

    The challenging task of automated handling of variable objects necessitates a combination of innovative engineering and advanced information technology. This paper describes the application of a recently developed control strategy applied to overcome some limitations of robot handling, particularly when dealing with variable objects. The paper focuses on a novel approach to accommodate the need for sensing and actuation in controlling the pickup procedure. An experimental robot-based system for the handling of soft parts, ranging from artificial components to natural objects such as fruit and meat pieces was developed. The configuration comprises a modular gripper subsystem, and an industrial robot as part of a distributed control system. The gripper subsystem features manually configurable fingers with integrated sensing capabilities. The control architecture is based on a concept of decentralized control differentiating between positioning and gripping procedures. In this way, the robot and gripper systems are treated as individual handling operations. THis concept allows very short set-up times for future changes involving one or more sub-systems.

  3. Biowaste home composting: experimental process monitoring and quality control.

    PubMed

    Tatàno, Fabio; Pagliaro, Giacomo; Di Giovanni, Paolo; Floriani, Enrico; Mangani, Filippo

    2015-04-01

    Because home composting is a prevention option in managing biowaste at local levels, the objective of the present study was to contribute to the knowledge of the process evolution and compost quality that can be expected and obtained, respectively, in this decentralized option. In this study, organized as the research portion of a provincial project on home composting in the territory of Pesaro-Urbino (Central Italy), four experimental composters were first initiated and temporally monitored. Second, two small sub-sets of selected provincial composters (directly operated by households involved in the project) underwent quality control on their compost products at two different temporal steps. The monitored experimental composters showed overall decreasing profiles versus composting time for moisture, organic carbon, and C/N, as well as overall increasing profiles for electrical conductivity and total nitrogen, which represented qualitative indications of progress in the process. Comparative evaluations of the monitored experimental composters also suggested some interactions in home composting, i.e., high C/N ratios limiting organic matter decomposition rates and final humification levels; high moisture contents restricting the internal temperature regime; nearly horizontal phosphorus and potassium evolutions contributing to limit the rates of increase in electrical conductivity; and prolonged biowaste additions contributing to limit the rate of decrease in moisture. The measures of parametric data variability in the two sub-sets of controlled provincial composters showed decreased variability in moisture, organic carbon, and C/N from the seventh to fifteenth month of home composting, as well as increased variability in electrical conductivity, total nitrogen, and humification rate, which could be considered compatible with the respective nature of decreasing and increasing parameters during composting. The modeled parametric kinetics in the monitored experimental

  4. Active flow separation control by a position-based iterative learning control algorithm with experimental validation

    NASA Astrophysics Data System (ADS)

    Cai, Zhonglun; Chen, Peng; Angland, David; Zhang, Xin

    2014-03-01

    A novel iterative learning control (ILC) algorithm was developed and applied to an active flow control problem. The technique uses pulsed air jets to delay flow separation on a two-element high-lift wing. The ILC algorithm uses position-based pressure measurements to update the actuation. The method was experimentally tested on a wing model in a 0.9 m × 0.6 m low-speed wind tunnel at the University of Southampton. Compressed air and fast switching solenoid valves were used as actuators to excite the flow, and the pressure distribution around the chord of the wing was measured as a feedback control signal for the ILC controller. Experimental results showed that the actuation was able to delay the separation and increase the lift by approximately 10%-15%. By using the ILC algorithm, the controller was able to find the optimum control input and maintain the improvement despite sudden changes of the separation position.

  5. Women's experiences as members of attention control and experimental intervention groups in a randomized controlled trial.

    PubMed

    Beal, Claudia C; Stuifbergen, Alexa; Volker, Deborah; Becker, Heather

    2009-12-01

    Attention control groups are often used in research testing the efficacy of psychosocial and behavioural interventions in order to control for placebo effects. The authors conducted a descriptive qualitative study to investigate how participants viewed their experiences in attention control and experimental intervention groups following a randomized controlled trial for women with fibromyalgia syndrome. Moderately structured interviews were conducted with 18 women (12 from the experimental intervention group and 6 from the attention control group). Members of the control group reported some benefits but few behavioural changes as a result of participating in the RCT, and some participants expressed disappointment at not receiving the intervention. Perceptions of changes in attitudes towards fibromyalgia syndrome and behaviours reported by the intervention group appear to be consistent with the theory underlying the intervention. Possible placebo effects identified in both groups include negative and positive social interactions with other participants.

  6. Effect of an Intervention on Observed Sun Protection by Vacationers in a Randomized Controlled Trial at North American Resorts

    PubMed Central

    Buller, David B.; Andersen, Peter A.; Walkosz, Barbara J.; Scott, Michael D.; Beck, Larry; Cutter, Gary R.

    2017-01-01

    During vacations, many individuals receive high-risk sun exposure that is associated with skin cancer. Vacationers in outdoor recreation venues (pretest n=4,347; posttest n=3,986) at warm-weather destination resorts in North America (n=41) were enrolled in a pair-matched, group-randomized pretest-posttest controlled quasi-experimental design in 2012-14. Print, audiovisual, and online messages based on Transportation Theory and Diffusion of Innovation Theory and promoting advanced sun protection (e.g., use of clothing, hats, shade and pre-application/reapplication of sunscreen and reliable cues to high UV) were delivered through resort channels. Vacationers' sun protection practices observed by trained research staff (i.e., body coverage and shade use analyzed individually and in combined scores) did not differ by experimental condition (p>0.05) or intervention implementation (p>0.05). However, recreation venue moderated intervention impact. The intervention improved sun protection at waterside recreation venues (z-score composite: intervention pre=-22.74, post=-15.77; control pre=-27.24, post=-23.24) but not non-waterside venues (z-score composite: intervention pre=20.43, post=20.53; control pre=22.94, post=18.03, p<0.01). An additional analysis showed that resorts with greater program implementation showed more improvements in sun protection by vacationers at waterside (z=score composite: high implementation pre=-25.45, post=-14.05; low implementation pre=-24.70, post=-21.40) compared to non-waterside (z-score composite: high implementation pre=14.51, post=19.98; low implementation pre=24.03, post=18.98, p<0.01) recreation venues. The intervention appeared effective with the vacationers in recreation venues with the highest-risk for sun exposure, waterside venues. However, it was not effective throughout all the resort venues, possibly because of the sun-seeking desires of vacationers, information overload at the resorts, and constraints on clothing styles and sun

  7. Effect of an intervention on observed sun protection by vacationers in a randomized controlled trial at North American resorts.

    PubMed

    Buller, David B; Andersen, Peter A; Walkosz, Barbara J; Scott, Michael D; Beck, Larry; Cutter, Gary R

    2017-06-01

    During vacations, many individuals receive high-risk sun exposure that is associated with skin cancer. Vacationers in outdoor recreation venues (pretest n=4347; posttest n=3986) at warm-weather destination resorts in North America (n=41) were enrolled in a pair-matched, group-randomized pretest-posttest controlled quasi-experimental design in 2012-14. Print, audiovisual, and online messages based on Transportation Theory and Diffusion of Innovation Theory and promoting advanced sun protection (e.g., use of clothing, hats, shade and pre-application/reapplication of sunscreen and reliable cues to high UV) were delivered through resort channels. Vacationers' sun protection practices observed by trained research staff (i.e., body coverage and shade use analyzed individually and in combined scores) did not differ by experimental condition (p>0.05) or intervention implementation (p>0.05). However, recreation venue moderated intervention impact. The intervention improved sun protection at waterside recreation venues (z-score composite: intervention pre=-22.74, post=-15.77; control pre=-27.24, post=-23.24) but not non-waterside venues (z-score composite: intervention pre=20.43, post=20.53; control pre=22.94, post=18.03, p<0.01). An additional analysis showed that resorts with greater program implementation showed more improvements in sun protection by vacationers at waterside (z=score composite: high implementation pre=-25.45, post=-14.05; low implementation pre=-24.70, post=-21.40) compared to non-waterside (z-score composite: high implementation pre=14.51, post=19.98; low implementation pre=24.03, post=18.98, p<0.01) recreation venues. The intervention appeared effective with the vacationers in recreation venues with the highest-risk for sun exposure, waterside venues. However, it was not effective throughout all the resort venues, possibly because of the sun-seeking desires of vacationers, information overload at the resorts, and constraints on clothing styles and sun

  8. Controlling Flexible Manipulators, an Experimental Investigation. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Hastings, Gordon Greene

    1986-01-01

    Lightweight, slender manipulators offer faster response and/or greater workspace range for the same size actuators than tradional manipulators. Lightweight construction of manipulator links results in increased structural flexibility. The increase flexibility must be considered in the design of control systems to properly account for the dynamic flexible vibrations and static deflections. Real time control of the flexible manipulator vibrations are experimentally investigated. Models intended for real-time control of distributed parameter system such as flexible manipulators rely on model approximation schemes. An linear model based on the application of Lagrangian dynamics to a rigid body mode and a series of separable flexible modes is examined with respect to model order requirements, and modal candidate selection. Balanced realizations are applied to the linear flexible model to obtain an estimate of appropriate order for a selected model. Describing the flexible deflections as a linear combination of modes results in measurements of beam state, which yield information about several modes. To realize the potential of linear systems theory, knowledge of each state must be available. State estimation is also accomplished by implementation of a Kalman Filter. State feedback control laws are implemented based upon linear quadratic regulator design.

  9. Reduced-Sodium Lunches Are Well-Accepted by Uninformed Consumers Over a 3-Week Period and Result in Decreased Daily Dietary Sodium Intakes: A Randomized Controlled Trial.

    PubMed

    Janssen, Anke M; Kremer, Stefanie; van Stipriaan, Willeke L; Noort, Martijn W J; de Vries, Jeanne H M; Temme, Elisabeth H M

    2015-10-01

    Processed foods are major contributors to excessive sodium intake in Western populations. We investigated the effect of food reformulation on daily dietary sodium intake. To determine whether uninformed consumers accept reduced-sodium lunches and to determine the effect of consuming reduced-sodium lunches on 24-hour urinary sodium excretion. A single-blind randomized controlled pretest-posttest design with two parallel treatment groups was used. Participants chose foods in an experimental real-life canteen setting at the Restaurant of the Future in Wageningen, the Netherlands, from May 16 until July 1, 2011. After a run-in period with regular foods for both groups, the intervention group (n=36) consumed foods with 29% to 61% sodium reduction (some were partially flavor compensated). The control group (n=38) continued consuming regular foods. Outcomes for assessment of acceptance were the amount of foods consumed, energy and sodium intake, remembered food liking, and intensity of sensory aspects. Influence on daily dietary sodium intake was assessed by 24-hour urinary sodium excretion. Between and within-subject comparisons were assessed by analysis of covariance. Energy intake and amount consumed of each food category per lunch remained similar for both groups. Compared with the control group, the intervention group's sodium intake per lunch was significantly reduced by -1,093 mg (adjusted difference) (95% CI -1,285 to -901), equivalent to 43 mmol sodium. Remembered food liking, taste intensity, and saltiness were scored similarly for almost all of the reduced-sodium foods compared with the regular foods. After consuming reduced-sodium lunches, compared with the control group, intervention participants' 24-hour urinary sodium excretion was significantly lower by -40 mEq (adjusted difference) (95% CI -63 to -16) than after consuming regular lunches, and this reflects a decreased daily sodium intake of 1 g. Comparing the two treatment groups, consumption of reduced

  10. Long-term effects of nurse-led individualized education on middle-aged patients with acute coronary synrome: a quasi-experimental study.

    PubMed

    Shim, Jae Lan; Hwang, Seon Young

    2017-01-01

    This study examined the long-term effects of nurse-led, individualized education on self-efficacy, self-care compliance, and health-related quality of life (HRQoL) in middle-aged patients with new-onset acute coronary syndrome . A quasi-experimental pretest-posttest design was used in the study. A cardiovascular nurse provided individualized education to the intervention group ( n  = 32), and self-efficacy, self-care compliance, and HRQoL at baseline and 3 and 12 months after discharge were compared to those of a control group ( n  = 30). Patients were recruited from a cardiovascular care unit at a university hospital between 2012 and 2013. Repeated measures analysis of variance was used to compare time-related changes. There was no significant difference in self-efficacy between the 2 groups over a fixed period ( F  = 3.47, p  = 0.067) and showed no interaction between the 2 groups ( F  = 0.45, p  = 0.636). However, significant differences were found in the main and interaction effects between the 2 groups and changes in self-care compliance over the follow-up period differed significantly between the 2 groups ( F  = 28.72, p  < 0.001). Changes in mental HRQoL over the follow-up period differed significantly between the 2 groups ( F  = 33.34, p  < 0.001) and significant interaction effect ( F  = 4.40, p  = 0.040). Structured nurse-led education should be provided to middle-aged patients with new-onset acute coronary syndrome, as part of routine predischarge education, to increase self-care compliance and mental HRQoL and prevent secondary adverse events. Trial registration number (TRN) is KCT0002454. The study was registered retrospectively with registration date July 9, 2017.

  11. Developing students’ learning achievement and experimental skills on buoyancy and the involvement of Newton’s third law through experimental sets

    NASA Astrophysics Data System (ADS)

    Chokchai, Jaewijarn; Khanti, Toedtanya; Sura, Wuttiprom

    2017-09-01

    The purposes of this research were: to construct packages of operations on buoyancy and the involvement of Newton’s third law, to enhance achievement score of students on buoyancy and the involvement of Newton’s third law, to enhance experimental skills on buoyancy and the involvement of Newton’s third law and to evaluate students’ attitude towards the packages of operations on buoyancy and the involvement of Newton’s third law using inquiry method. The samples were 42 grade 11 students in academic year 2016 at Hatyaiwittayalai School, Hatyai, Songkhla. The research method was one group pretest-posttest design. The research tools consisted of experimental set on buoyancy and the involvement of Newton’s third law, the learning achievement test on buoyancy and the involvement of Newton’s third law and the students’ attitude questionnaires. The experimental skills of most students was in a good level . The satisfaction of most students was in a good level. The research showed the learning achievement after instruction higher than that before instruction using experimental set at the significant level of 0.05 and the class average normalized gain is in the medium gain

  12. Experimental system for the control of surgically induced infections

    NASA Technical Reports Server (NTRS)

    1971-01-01

    The results are presented of the development tests performed on the experimental system for the control of surgically induced infections. Tests were performed on the portable clean room to demonstrate assembly, collapsability, portability and storage. Collapsing, relocating and storing within the surgery room can be accomplished in 12 minutes. The storage envelope dimensions are 1.64 m x 4.24 m x 2.62 m high. The disassembly transfer to another room, and reassembly were demonstrated. The laminar air flow velocity profile within the enclosure was measured. In the undisturbed area of the enclosure the air flow met the Federal Standard 209a requirements of 27.45 meters per minute + or - 6.10 meters per minute. Smoke tests with simulated surgery equipment and personnel in the enclosure did not indicate any detrimental air flow patterns. It is concluded that the system as designed will perform the functions required for its intended use.

  13. Low-Pressure Turbine Separation Control: Comparison With Experimental Data

    NASA Technical Reports Server (NTRS)

    Garg, Vijay K.

    2002-01-01

    The present work details a computational study, using the Glenn HT code, that analyzes the use of vortex generator jets (VGJs) to control separation on a low-pressure turbine (LPT) blade at low Reynolds numbers. The computational results are also compared with the experimental data for steady VGJs. It is found that the code determines the proper location of the separation point on the suction surface of the baseline blade (without any VGJ) for Reynolds numbers of 50,000 or less. Also, the code finds that the separated region on the suction surface of the blade vanishes with the use of VGJs. However, the separated region and the wake characteristics are not well predicted. The wake width is generally over-predicted while the wake depth is under-predicted.

  14. Experimental active control of sound in the ATR 42

    NASA Astrophysics Data System (ADS)

    Paonessa, A.; Sollo, A.; Paxton, M.; Purver, M.; Ross, C. F.

    Passenger comfort is becoming day by day an important issue for the market of the regional turboprop aircraft and also for the future high speed propeller driven aircraft. In these aircraft the main contribution to the passenger annoyance is due to the propeller noise blade passing frequency (BPF) and its harmonics. In the recent past a detailed theoretical and experimental work has been done by Alenia Aeronautica in order to reduce the noise level in the ATR aircraft passenger cabin by means of conventional passive treatments: synchrophasing of propellers, dynamic vibration absorbers, structural reinforcements, damping materials. The application of these treatments has been introduced on production aircraft with a remarkable improvement of noise comfort but with a significant weight increase. For these reasons, a major technology step is required for reaching passenger comfort comparable to that of jet aircraft with the minimum weight increase. The most suitable approach to this problem has been envisaged in the active noise control which consists in generating an anti-sound field in the passenger cabin to reduce the noise at propeller BPF and its harmonics. The attenuation is reached by means of a control system which acquires information about the cabin noise distribution and the propeller speed during flight and simultaneously generates the signals to drive the speakers.

  15. Evaluating Intervention Effects in a Diagnostic Classification Model Framework

    ERIC Educational Resources Information Center

    Madison, Matthew J.; Bradshaw, Laine

    2018-01-01

    The evaluation of intervention effects is an important objective of educational research. One way to evaluate the effectiveness of an intervention is to conduct an experiment that assigns individuals to control and treatment groups. In the context of pretest/posttest designed studies, this is referred to as a control-group pretest/posttest design.…

  16. New experimental approaches to the biology of flight control systems.

    PubMed

    Taylor, Graham K; Bacic, Marko; Bomphrey, Richard J; Carruthers, Anna C; Gillies, James; Walker, Simon M; Thomas, Adrian L R

    2008-01-01

    Here we consider how new experimental approaches in biomechanics can be used to attain a systems-level understanding of the dynamics of animal flight control. Our aim in this paper is not to provide detailed results and analysis, but rather to tackle several conceptual and methodological issues that have stood in the way of experimentalists in achieving this goal, and to offer tools for overcoming these. We begin by discussing the interplay between analytical and empirical methods, emphasizing that the structure of the models we use to analyse flight control dictates the empirical measurements we must make in order to parameterize them. We then provide a conceptual overview of tethered-flight paradigms, comparing classical ;open-loop' and ;closed-loop' setups, and describe a flight simulator that we have recently developed for making flight dynamics measurements on tethered insects. Next, we provide a conceptual overview of free-flight paradigms, focusing on the need to use system identification techniques in order to analyse the data they provide, and describe two new techniques that we have developed for making flight dynamics measurements on freely flying birds. First, we describe a technique for obtaining inertial measurements of the orientation, angular velocity and acceleration of a steppe eagle Aquila nipalensis in wide-ranging free flight, together with synchronized measurements of wing and tail kinematics using onboard instrumentation and video cameras. Second, we describe a photogrammetric method to measure the 3D wing kinematics of the eagle during take-off and landing. In each case, we provide demonstration data to illustrate the kinds of information available from each method. We conclude by discussing the prospects for systems-level analyses of flight control using these techniques and others like them.

  17. Resource use and costs of type 2 diabetes patients receiving managed or protocolized primary care: a controlled clinical trial.

    PubMed

    van der Heijden, Amber A W A; de Bruijne, Martine C; Feenstra, Talitha L; Dekker, Jacqueline M; Baan, Caroline A; Bosmans, Judith E; Bot, Sandra D M; Donker, Gé A; Nijpels, Giel

    2014-06-25

    The increasing prevalence of diabetes is associated with increased health care use and costs. Innovations to improve the quality of care, manage the increasing demand for health care and control the growth of health care costs are needed. The aim of this study is to evaluate the care process and costs of managed, protocolized and usual care for type 2 diabetes patients from a societal perspective. In two distinct regions of the Netherlands, both managed and protocolized diabetes care were implemented. Managed care was characterized by centralized organization, coordination, responsibility and centralized annual assessment. Protocolized care had a partly centralized organizational structure. Usual care was characterized by a decentralized organizational structure. Using a quasi-experimental control group pretest-posttest design, the care process (guideline adherence) and costs were compared between managed (n = 253), protocolized (n = 197), and usual care (n = 333). We made a distinction between direct health care costs, direct non-health care costs and indirect costs. Multivariate regression models were used to estimate differences in costs adjusted for confounding factors. Because of the skewed distribution of the costs, bootstrapping methods (5000 replications) with a bias-corrected and accelerated approach were used to estimate 95% confidence intervals (CI) around the differences in costs. Compared to usual and protocolized care, in managed care more patients were treated according to diabetes guidelines. Secondary health care use was higher in patients under usual care compared to managed and protocolized care. Compared to usual care, direct costs were significantly lower in managed care (€-1.181 (95% CI: -2.597 to -334)) while indirect costs were higher (€ 758 (95% CI: -353 to 2.701), although not significant. Direct, indirect and total costs were lower in protocolized care compared to usual care (though not significantly). Compared to usual care, managed

  18. Resource use and costs of type 2 diabetes patients receiving managed or protocolized primary care: a controlled clinical trial

    PubMed Central

    2014-01-01

    Background The increasing prevalence of diabetes is associated with increased health care use and costs. Innovations to improve the quality of care, manage the increasing demand for health care and control the growth of health care costs are needed. The aim of this study is to evaluate the care process and costs of managed, protocolized and usual care for type 2 diabetes patients from a societal perspective. Methods In two distinct regions of the Netherlands, both managed and protocolized diabetes care were implemented. Managed care was characterized by centralized organization, coordination, responsibility and centralized annual assessment. Protocolized care had a partly centralized organizational structure. Usual care was characterized by a decentralized organizational structure. Using a quasi-experimental control group pretest-posttest design, the care process (guideline adherence) and costs were compared between managed (n = 253), protocolized (n = 197), and usual care (n = 333). We made a distinction between direct health care costs, direct non-health care costs and indirect costs. Multivariate regression models were used to estimate differences in costs adjusted for confounding factors. Because of the skewed distribution of the costs, bootstrapping methods (5000 replications) with a bias-corrected and accelerated approach were used to estimate 95% confidence intervals (CI) around the differences in costs. Results Compared to usual and protocolized care, in managed care more patients were treated according to diabetes guidelines. Secondary health care use was higher in patients under usual care compared to managed and protocolized care. Compared to usual care, direct costs were significantly lower in managed care (€-1.181 (95% CI: -2.597 to -334)) while indirect costs were higher (€758 (95% CI: -353 to 2.701), although not significant. Direct, indirect and total costs were lower in protocolized care compared to usual care (though not

  19. An Experimental Study to Control Scour at River Confluence

    NASA Astrophysics Data System (ADS)

    Wuppukondur, A.; Chandra, V.

    2015-12-01

    The aim of present study is finding a method to control sediment erosion at river confluence. The confluences are mixture of two different flows and are common occurrences along the river. River confluences are sites of natural scour phenomenon and also influence reservoir sedimentation. The river confluence is associated with a separation zone, stagnation zone and a mixing layer along which the scour hole is observed. The eroded sediment creates potential problems by depositing at unwanted downstream locations such as barrages, weirs, check dams, reservoirs etc. As per the literature, the storage capacity of major reservoirs in India is going to be reduced nearly half of the storage capacity by 2020. Hence, an experimental study has been conducted on mobile bed (d50=0.28 mm) with a confluence angle of 90o for a discharge ratio (Qr) of 0.5, where, Qr is defined as the ratio between lateral flow discharge (Ql) and main flow discharge (Qm). Circular shape pile models of same diameter are arranged in a systematic manner with constant spacing (5 cm, 10 cm and 15 cm) to change the flow pattern for reducing scour at the confluence. Two types of pile models (8 mm ϕ and 12 mm ϕ) are used to conduct the experiments. The experimental results show that maximum scour depth at confluence is reduced by 60%. In addition, the bed profile modifications are also reported. Keywords: Reservoir sedimentation, River confluence, Mobile bed, Scour, Vanes. References:1. Borghei, S. M., and Sahebari, A. J. (2010). "Local Scour at Open-Channel Junctions", Journal of Hydraulic Research, 48(4), 37 - 41. 2. Kothyari, U. C. (1996). "Methods for Estimation Sediment Yield from Catchments", Proc., Int. Sem. On Civil Engg. Practices in Twenty First Century, Roorkee, India, 1071-1086. 3. Mosley, M. P. (1976) "An Experimental Study of Channel Confluences". The Journal of Geology, 84(55), 532-562. 4. Ouyang, H. T. (2009). "Investigation on the dimensions and shape of a submerged vane for sediment

  20. Lithium control on experimental serpentinization processes: implications for natural systems

    NASA Astrophysics Data System (ADS)

    Lafay, Romain; Janots, Emilie; Montes-Hernandez, German

    2014-05-01

    Fluid mobile elements such as As, B, Li or Sb are of prime importance to trace fluid-rock interactions in the oceanic lithosphere from its hydrothermal alteration at the ocean ridge up to its dehydration in deep subduction. Although the cycle of fluid mobile elements is increasingly studied, their partitioning between fluid and mineral are still poorly know and their role on mechanism and kinetic of serpentinization reaction have been neglected. In the present experimental study supported by two kinds of experiments, we focussed on Li study and highlighted that this element play a substantial role on serpentinization reaction kinetic/mechanism and on serpentine textural properties. Indeed, in presence of 200 µg g-1 of dissolved Li alteration rate is 2-4 time faster with respect to olivine alteration reactions in undoped system (1) at same experimental conditions (alkaline solution, T = 200°C, Psat ~16 bar, olivine grains < 150μm). Moreover, serpentinization reaction mechanism is modified in presence of Li and characterized by a decoupling between olivine dissolution and serpentine precipitation. The control of olivine grain size on Li distribution between serpentinization products and fluid suggests for Li sequestration by an adsorption mechanism. Additionaly, with respect to pure chrysotile sythesis (2) we indicated that Li strongly affect chrysotile sizes and morphology especially by favoring wider particles precipitation and stabilizing lizardite (3). Experimental distribution coefficients obtains in both systems are compatible with measurements made on abyssal serpentinites and hydrothermal fluids. These remarkable results increase our ability for understanding the fate of Li during fluid/olivine interaction and its retroactive effect on serpentinization reactions. At mid ocean ridge this may explain Li heterogeneous distributions and links between chemical and mineralogical observations. Moreover in subduction environments, where fluids released from the

  1. Mentors Offering Maternal Support (M.O.M.S.)

    DTIC Science & Technology

    2011-08-02

    at Sessions 1, 5, and 8. Table 1. Pretest - posttest , randomized, controlled, repeated measured design Experimental Intervention Sessions...theoretical mediators of self-esteem and emotional support (0.6 standard deviation change from pretest to posttest ) with reduction of effect to 0.4...always brought back to the designated topic . In order to have statistically significant results for the outcome variables the study sessions must

  2. Does Exercise Improve Cognitive Performance? A Conservative Message from Lord's Paradox.

    PubMed

    Liu, Sicong; Lebeau, Jean-Charles; Tenenbaum, Gershon

    2016-01-01

    Although extant meta-analyses support the notion that exercise results in cognitive performance enhancement, methodology shortcomings are noted among primary evidence. The present study examined relevant randomized controlled trials (RCTs) published in the past 20 years (1996-2015) for methodological concerns arise from Lord's paradox. Our analysis revealed that RCTs supporting the positive effect of exercise on cognition are likely to include Type I Error(s). This result can be attributed to the use of gain score analysis on pretest-posttest data as well as the presence of control group superiority over the exercise group on baseline cognitive measures. To improve accuracy of causal inferences in this area, analysis of covariance on pretest-posttest data is recommended under the assumption of group equivalence. Important experimental procedures are discussed to maintain group equivalence.

  3. Does Exercise Improve Cognitive Performance? A Conservative Message from Lord's Paradox

    PubMed Central

    Liu, Sicong; Lebeau, Jean-Charles; Tenenbaum, Gershon

    2016-01-01

    Although extant meta-analyses support the notion that exercise results in cognitive performance enhancement, methodology shortcomings are noted among primary evidence. The present study examined relevant randomized controlled trials (RCTs) published in the past 20 years (1996–2015) for methodological concerns arise from Lord's paradox. Our analysis revealed that RCTs supporting the positive effect of exercise on cognition are likely to include Type I Error(s). This result can be attributed to the use of gain score analysis on pretest-posttest data as well as the presence of control group superiority over the exercise group on baseline cognitive measures. To improve accuracy of causal inferences in this area, analysis of covariance on pretest-posttest data is recommended under the assumption of group equivalence. Important experimental procedures are discussed to maintain group equivalence. PMID:27493637

  4. Children's Understanding of Experimental Contrast and Experimental Control: An Inventory for Primary School

    ERIC Educational Resources Information Center

    Osterhaus, Christopher; Koerber, Susanne; Sodian, Beate

    2015-01-01

    Experimentation skills are a central component of scientific thinking, and many studies have investigated whether and when primary-school children develop adequate experimentation strategies. However, the answers to these questions vary substantially depending on the type of task that is used: while discovery tasks, which require children to…

  5. Controlled human infection with RSV: The opportunities of experimental challenge.

    PubMed

    Habibi, Maximillian S; Chiu, Christopher

    2017-01-11

    Despite the recent explosion in RSV vaccine development, there remain substantial hurdles to overcome before licensing of effective vaccines will allow widespread use, particularly in high-risk populations. Incomplete understanding of mechanisms and correlates of protection against RSV mean that, for the time being, successful RSV vaccines must directly demonstrate efficacy, which necessitates large and costly clinical trials in naturally infected patients. To mitigate the risks inherent in progressing to these late-stage trials, experimental human RSV infection studies have recently been re-established, representing the interface between pre-clinical models and observational studies of patients. Not only can they be used for early proof-of-concept clinical trials to test vaccine efficacy, but human challenge studies also offer the potential to better understand protective immunity against RSV infection to improve vaccine design and delivery. In the past, controlled human infection studies with RSV have been instrumental in elucidating the influence of factors such as route of infection and type of inoculum on the course of disease. Recently, efficacy trials of novel RSV antiviral drugs have also been successfully undertaken. Now, with advances in technology, detailed investigations of human mucosal immunity in the RSV-infected airway are possible. These have indicated defects in RSV-induced humoral and CD8+ T cell immunity that may contribute to the recurrent symptomatic infection that occurs throughout life and should be circumvented by optimal vaccines. Here, we discuss the insights derived from RSV human challenge models; the major impediments to their more widespread uptake; and their potential benefit in accelerating vaccine development, including future directions to further enhance the relevance of these models to at-risk patient populations. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.

  6. The effectiveness of a nurse-delivered breast health promotion program on breast cancer screening behaviours in non-adherent Turkish women: A randomized controlled trial.

    PubMed

    Secginli, Selda; Nahcivan, Nursen O

    2011-01-01

    Few studies have investigated breast health programs to promote rates of having a mammography, clinical breast examination and breast self-examination among non-adherent Turkish women. To determine the effectiveness of a breast health promotion program on mammography and clinical breast examination use, breast self-examination frequency and proficiency (breast self-examination skills and lump detection), breast health knowledge and health beliefs about breast cancer screening in a sample of Turkish women. Experimental (pretest-posttest control group). A community-based setting in Istanbul, Turkey. 190 Non-adherent women (intervention group=97, control group=93) aged 41 and older, residing in Istanbul, Turkey. The intervention group (n=97) received a 120-min breast health promotion program based on health belief model including a breast health education, film, breast self-examination instruction, and a booklet, a calendar, a card designed specifically for the study. The control group (n=93) received general information except breast health. Data were collected before the program, immediately after the program, and at 3- and 6-month post-program. The outcome measures are the mammography, clinical breast examination, and breast self-examination frequency, breast self-examination proficiency, breast health knowledge, and health beliefs (perceived susceptibility to breast cancer, benefits to mammography and breast self-examination, barriers of mammography and breast self-examination, confidence in performing breast self-examination). The breast health promotion program significantly increased breast self-examination frequency and proficiency and breast health knowledge. No significant differences existed in mammography and clinical breast examination rates between the two groups at 6 months. The program was effective in increasing perceived susceptibility to breast cancer, perceived benefits of mammography and breast self-examination, and confidence of breast self

  7. Using the Teach-Back Method in Patient Education to Improve Patient Satisfaction.

    PubMed

    Centrella-Nigro, Andrea M; Alexander, Catherine

    2017-01-01

    This quasi-experimental research study used two similar nursing units to test the effects of teach back on Hospital Consumer Assessment of Healthcare Providers and Systems (HCAHPS) scores. A pretest-posttest design tested 24 nurses' knowledge, attitudes, and beliefs about teach back. Education specialists provided a 1-hour teaching session on teach back to all nurses in the intervention unit. A significant improvement in knowledge scores in the pretest-posttest was found using paired t tests (p = .002). Qualitative analysis of nurses' comments demonstrated strong support for teach back in the post-test. The HCAHPS scores were not significantly improved in the intervention unit when compared with the control unit. More research needs to be conducted to determine the effectiveness of teach back on HCAHPS scores. J Contin Educ Nurs. 2017;48(1):47-52. Copyright 2017, SLACK Incorporated.

  8. Experimental evaluation of model predictive control and inverse dynamics control for spacecraft proximity and docking maneuvers

    NASA Astrophysics Data System (ADS)

    Virgili-Llop, Josep; Zagaris, Costantinos; Park, Hyeongjun; Zappulla, Richard; Romano, Marcello

    2018-03-01

    An experimental campaign has been conducted to evaluate the performance of two different guidance and control algorithms on a multi-constrained docking maneuver. The evaluated algorithms are model predictive control (MPC) and inverse dynamics in the virtual domain (IDVD). A linear-quadratic approach with a quadratic programming solver is used for the MPC approach. A nonconvex optimization problem results from the IDVD approach, and a nonlinear programming solver is used. The docking scenario is constrained by the presence of a keep-out zone, an entry cone, and by the chaser's maximum actuation level. The performance metrics for the experiments and numerical simulations include the required control effort and time to dock. The experiments have been conducted in a ground-based air-bearing test bed, using spacecraft simulators that float over a granite table.

  9. The short-term health and psychosocial impacts of domestic energy efficiency investments in low-income areas: a controlled before and after study.

    PubMed

    Grey, Charlotte N B; Jiang, Shiyu; Nascimento, Christina; Rodgers, Sarah E; Johnson, Rhodri; Lyons, Ronan A; Poortinga, Wouter

    2017-01-31

    Research suggests that living in fuel poverty and cold homes contributes to poor physical and mental health, and that interventions targeted at those living in poor quality housing may lead to health improvements. However, little is known about the socio-economic intermediaries and processes that contribute to better health. This study examined the relationship between energy efficiency investments to homes in low-income areas and mental and physical health of residents, as well as a number of psychosocial outcomes likely to be part of the complex relationship between energy efficiency measures and health outcomes. A quasi-experimental field study with a controlled pretest-posttest design was conducted (intervention n = 364; control n = 418) to investigate the short-term health and psychosocial impacts of a domestic energy efficiency programme that took place across Wales between 2013 and 2015. Survey data were collected in the winters before and after installation of energy efficiency measures, including external wall insulation. The study used a multilevel modelling repeated measures approach to analyse the data. The energy efficiency programme was not associated with improvements in physical and mental health (using the SF-12v2 physical and mental health composite scales) or reductions in self-reported respiratory and asthma symptoms. However, the programme was associated with improved subjective wellbeing (B = 0.38, 95% CI 0.12 to 0.65), as well as improvements in a number of psychosocial outcomes, including increased thermal satisfaction (OR = 3.83, 95% CI 2.40 to 5.90), reduced reports of putting up with feeling cold to save heating costs (OR = 0.49, CI = 0.25 to 0.94), fewer financial difficulties (B = -0.15, 95% CI -0.25 to -0.05), and reduced social isolation (OR = 0.32, 95% CI 0.13 to 0.77). The study showed that investing in energy efficiency in low-income communities does not lead to self-reported health improvements in the

  10. Analysis and Experimentation of Control Strategies for Underactuated Spacecraft

    DTIC Science & Technology

    2009-09-01

    control techniques that provide time -invariant global asymptotic stability of the fully actuated spacecraft system of equations. Although these control ...momentum wheel actuators in finite time under the restriction that the total angular momentum vector of the system is zero. This control methodology...can be stabilizable to an arbitrarily small region about the equilibrium of the system via time -invariant smooth state feedback control

  11. Experimental Control of Thermocapillary Convection in a Liquid Bridge

    NASA Technical Reports Server (NTRS)

    Petrov, Valery; Schatz, Michael F.; Muehlner, Kurt A.; VanHook, Stephen J.; McCormick, W. D.; Swift, Jack B.; Swinney, Harry L.

    1996-01-01

    We demonstrate the stabilization of an isolated unstable periodic orbit in a liquid bridge convection experiment. A model independent, nonlinear control algorithm uses temperature measurements near the liquid interface to compute control perturbations which are applied by a thermoelectric element. The algorithm employs a time series reconstruction of a nonlinear control surface in a high dimensional phase space to alter the system dynamics.

  12. 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

  13. Simulation and Experimental Investigation of Structural Dynamic Frequency Characteristics Control

    PubMed Central

    Zhang, Xingwu; Chen, Xuefeng; You, Shangqin; He, Zhengjia; Li, Bing

    2012-01-01

    In general, mechanical equipment such as cars, airplanes, and machine tools all operate with constant frequency characteristics. These constant working characteristics should be controlled if the dynamic performance of the equipment demands improvement or the dynamic characteristics is intended to change with different working conditions. Active control is a stable and beneficial method for this, but current active control methods mainly focus on vibration control for reducing the vibration amplitudes in the time domain or frequency domain. In this paper, a new method of dynamic frequency characteristics active control (DFCAC) is presented for a flat plate, which can not only accomplish vibration control but also arbitrarily change the dynamic characteristics of the equipment. The proposed DFCAC algorithm is based on a neural network including two parts of the identification implement and the controller. The effectiveness of the DFCAC method is verified by several simulation and experiments, which provide desirable results. PMID:22666072

  14. Simulation and experimental investigation of structural dynamic frequency characteristics control.

    PubMed

    Zhang, Xingwu; Chen, Xuefeng; You, Shangqin; He, Zhengjia; Li, Bing

    2012-01-01

    In general, mechanical equipment such as cars, airplanes, and machine tools all operate with constant frequency characteristics. These constant working characteristics should be controlled if the dynamic performance of the equipment demands improvement or the dynamic characteristics is intended to change with different working conditions. Active control is a stable and beneficial method for this, but current active control methods mainly focus on vibration control for reducing the vibration amplitudes in the time domain or frequency domain. In this paper, a new method of dynamic frequency characteristics active control (DFCAC) is presented for a flat plate, which can not only accomplish vibration control but also arbitrarily change the dynamic characteristics of the equipment. The proposed DFCAC algorithm is based on a neural network including two parts of the identification implement and the controller. The effectiveness of the DFCAC method is verified by several simulation and experiments, which provide desirable results.

  15. Control of Warm Compression Stations Using Model Predictive Control: Simulation and Experimental Results

    NASA Astrophysics Data System (ADS)

    Bonne, F.; Alamir, M.; Bonnay, P.

    2017-02-01

    This paper deals with multivariable constrained model predictive control for Warm Compression Stations (WCS). WCSs are subject to numerous constraints (limits on pressures, actuators) that need to be satisfied using appropriate algorithms. The strategy is to replace all the PID loops controlling the WCS with an optimally designed model-based multivariable loop. This new strategy leads to high stability and fast disturbance rejection such as those induced by a turbine or a compressor stop, a key-aspect in the case of large scale cryogenic refrigeration. The proposed control scheme can be used to achieve precise control of pressures in normal operation or to avoid reaching stopping criteria (such as excessive pressures) under high disturbances (such as a pulsed heat load expected to take place in future fusion reactors, expected in the cryogenic cooling systems of the International Thermonuclear Experimental Reactor ITER or the Japan Torus-60 Super Advanced fusion experiment JT-60SA). The paper details the simulator used to validate this new control scheme and the associated simulation results on the SBTs WCS. This work is partially supported through the French National Research Agency (ANR), task agreement ANR-13-SEED-0005.

  16. Experimental system for the control of surgically induced infections

    NASA Technical Reports Server (NTRS)

    Tevebaugh, M. D.

    1971-01-01

    The development tests to be performed on the experimental system are described in detail. The test equipment, conditions, and procedures are given. The portable clean room tests include assembly, collapsability, portability, and storage; laminar flow rate; static pressure; air flow pattern; and electrostatic buildup. The other tests are on the ventilation system, human factors evaluation, electrical subsystem, and material compatibility.

  17. Experimental system for the control of surgically induced infections

    NASA Technical Reports Server (NTRS)

    1972-01-01

    The experimental system is described, and the procedures for surgery usage and maintenance are outlined. Basically the system consists of the following: (1) a portable clean room comprised of a horizontal laminar flow filter system and a transparent walled enclosure, (2) a helmet-shoulder pad assembly, (3) a communications system, (4) a helmet ventilation system, and (5) surgical gowns.

  18. 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…

  19. The Mobile Advanced Command and Control Station (MACCS) Experimental Testbed

    DTIC Science & Technology

    2007-10-01

    were selected: Vehicle: Dodge (Sprinter 2500 high-roof - Mercedes - Benz vehicle) Electrical equipment and habitability equipment: Crossroads Coaches...this innovative , mobile, experimental tested. IMPACT/APPLICATIONS While MACCS clearly supports the research agenda for both HAL and ONR (as well as

  20. Software Considerations for Subscale Flight Testing of Experimental Control Laws

    NASA Technical Reports Server (NTRS)

    Murch, Austin M.; Cox, David E.; Cunningham, Kevin

    2009-01-01

    The NASA AirSTAR system has been designed to address the challenges associated with safe and efficient subscale flight testing of research control laws in adverse flight conditions. In this paper, software elements of this system are described, with an emphasis on components which allow for rapid prototyping and deployment of aircraft control laws. Through model-based design and automatic coding a common code-base is used for desktop analysis, piloted simulation and real-time flight control. The flight control system provides the ability to rapidly integrate and test multiple research control laws and to emulate component or sensor failures. Integrated integrity monitoring systems provide aircraft structural load protection, isolate the system from control algorithm failures, and monitor the health of telemetry streams. Finally, issues associated with software configuration management and code modularity are briefly discussed.

  1. Experimental validation of tonal noise control from subsonic axial fans using flow control obstructions

    NASA Astrophysics Data System (ADS)

    Gérard, Anthony; Berry, Alain; Masson, Patrice; Gervais, Yves

    2009-03-01

    This paper presents the acoustic performance of a novel approach for the passive adaptive control of tonal noise radiated from subsonic fans. Tonal noise originates from non-uniform flow that causes circumferentially varying blade forces and gives rise to a considerably larger radiated dipolar sound at the blade passage frequency (BPF) and its harmonics compared to the tonal noise generated by a uniform flow. The approach presented in this paper uses obstructions in the flow to destructively interfere with the primary tonal noise arising from various flow conditions. The acoustic radiation of the obstructions is first demonstrated experimentally. Indirect on-axis acoustic measurements are used to validate the analytical prediction of the circumferential spectrum of the blade unsteady lift and related indicators generated by the trapezoidal and sinusoidal obstructions presented in Ref. [A. Gérard, A. Berry, P. Masson, Y. Gervais, Modelling of tonal noise control from subsonic axial fans using flow control obstructions, Journal of Sound and Vibration (2008), this issue, doi: 10.1016/j.jsv.2008.09.027.] and also by cylindrical obstructions used in the literature. The directivity and sound power attenuation are then given in free field for the control of the BPF tone generated by rotor/outlet guide vane (OGV) interaction and the control of an amplified BPF tone generated by the rotor/OGV interaction with an added triangular obstruction between two outlet guide vanes to enhance the primary non-uniform flow. Global control was demonstrated in free field, attenuation up to 8.4 dB of the acoustic power at BPF has been measured. Finally, the aerodynamic performances of the automotive fan used in this study are almost not affected by the presence of the control obstruction.

  2. Experimental test results of a generalized parameter fuel control

    NASA Technical Reports Server (NTRS)

    Batterton, P. G.; Gold, H.

    1973-01-01

    Considerable interest has been generated recently in low cost jet propulsion systems. One of the more complicated components of jet engines is the fuel control. Results of an effort to develop a simpler hydromechanical fuel control are presented. This prototype fuel control was installed on a J85-GE-13 jet engine. Results show that the fuel control provided satisfactory engine performance at sea level static conditions over its normal nonafterburning operating range, including startup. Results of both bench and engine tests are presented; the difficulties encountered are described.

  3. Analysis and experimental studies of the control of hang gliders

    NASA Technical Reports Server (NTRS)

    Phillips, W. H.

    1974-01-01

    A theoretical analysis of the longitudinal and lateral characteristics of hang gliders in straight flight, pullups, and turns is presented. Some examples of the characteristics of a straight-wing configuration and a Rogallo-wing configuration are given. A means for improving the control of hang gliders while retaining the same basic control feel is proposed.

  4. EXPERIMENTAL PERFORMANCE OF A CONTROLLABLE-PITCH SUPERCAVITATING PROPELLER.

    DTIC Science & Technology

    Studies were made of cavitation performance and open-water characteristics of a controllable-pitch supercavitating propeller with two, three, and...By means of several numerical examples, the feasibility of using a controllable-pitch supercavitating propeller is demonstrated. A practical application to a hydrofoil boat is also presented. (Author)

  5. Experimental Characterization of Piezoelectric Radial Field Diaphragms for Fluidic Control

    NASA Technical Reports Server (NTRS)

    Bryant, R. G.; Kavli, S. E.; Thomas, R. A., Jr.; Darji, K. J.; Mossi, K. M.

    2004-01-01

    NASA has recently developed a new piezoelectric actuator, the Radial Field Diaphragm or RFD. This actuator uses a radially-directed electric field to generate concentric out-of-plane (Z-axis) motion that allows this packaged device to be used as a pump or valve diaphragm. In order to efficiently use this new active device, experimental determination of pressure, flow rate, mechanical work, power consumption and overall efficiency needs to be determined by actually building a pump. However, without an optimized pump design, it is difficult to assess the quality of the data, as these results are inherent to the actual pump. Hence, separate experiments must be conducted in order to generate independent results to help guide the design criteria and pump quality. This paper focuses on the experiments used to generate the RFD's operational parameters and then compares these results to the experimentally determined results of several types of ball pumps. Also discussed are how errors are inherently introduced into the experiments, the pump design, experimental hardware and their effects on the overall system efficiency.

  6. Experimental testing of axial induction based control strategies for wake control and wind farm optimization

    NASA Astrophysics Data System (ADS)

    Bartl, J.; Sætran, L.

    2016-09-01

    In state-of-the-art wind farms each turbine is controlled individually aiming for optimum turbine power not considering wake effects on downstream turbines. Wind farm control concepts aim for optimizing the overall power output of the farm taking wake interactions between the individual turbines into account. This experimental wind tunnel study investigates axial induction based control concepts. It is examined how the total array efficiency of two in-line model turbines is affected when the upstream turbine's tip speed ratio (λcontrol) or blade pitch angle (β-control) is modified. The focus is particularly directed on how the wake flow behind the upstream rotor is affected when its axial induction is reduced in order to leave more kinetic energy in the wake to be recovered by a downstream turbine. It is shown that the radial distribution of kinetic energy in the wake area can be controlled by modifying the upstream turbine's tip speed ratio. By pitching out the upstream turbine's blades, however, the available kinetic energy in the wake is increased at an equal rate over the entire blade span. Furthermore, the total array efficiency of the two turbine setup is mapped depending on the upstream turbines tip speed ratio and pitch angle. For a small turbine separation distance of x/D=3 the downstream turbine is able to recover the major part of the power lost on the upstream turbine. However, no significant increase in the two-turbine array efficiency is achieved by altering the upstream turbine's operation point away from its optimum.

  7. Identifying controlling variables for math computation fluency through experimental analysis: the interaction of stimulus control and reinforcing consequences.

    PubMed

    Hofstadter-Duke, Kristi L; Daly, Edward J

    2015-03-01

    This study investigated a method for conducting experimental analyses of academic responding. In the experimental analyses, academic responding (math computation), rather than problem behavior, was reinforced across conditions. Two separate experimental analyses (one with fluent math computation problems and one with non-fluent math computation problems) were conducted with three elementary school children using identical contingencies while math computation rate was measured. Results indicate that the experimental analysis with non-fluent problems produced undifferentiated responding across participants; however, differentiated responding was achieved for all participants in the experimental analysis with fluent problems. A subsequent comparison of the single-most effective condition from the experimental analyses replicated the findings with novel computation problems. Results are discussed in terms of the critical role of stimulus control in identifying controlling consequences for academic deficits, and recommendations for future research refining and extending experimental analysis to academic responding are made. © The Author(s) 2014.

  8. End-point controller design for an experimental two-link flexible manipulator using convex optimization

    NASA Technical Reports Server (NTRS)

    Oakley, Celia M.; Barratt, Craig H.

    1990-01-01

    Recent results in linear controller design are used to design an end-point controller for an experimental two-link flexible manipulator. A nominal 14-state linear-quadratic-Gaussian (LQG) controller was augmented with a 528-tap finite-impulse-response (FIR) filter designed using convex optimization techniques. The resulting 278-state controller produced improved end-point trajectory tracking and disturbance rejection in simulation and experimentally in real time.

  9. Experimental traffic control device testing at New Hampshire toll plazas.

    DOT National Transportation Integrated Search

    2007-06-01

    This report includes a description of the testing and evaluation methodology of the E-ZPassSM Purple Light Experiment. Purple lights with : advanced signs were installed as supplemental traffic control devices for northbound and southbound E-Zp...

  10. Experimental evaluation of active-member control of precision structures

    NASA Technical Reports Server (NTRS)

    Fanson, James; Blackwood, Gary; Chu, Cheng-Chih

    1989-01-01

    The results of closed loop experiments that use piezoelectric active-members to control the flexible motion of a precision truss structure are described. These experiments are directed toward the development of high-performance structural systems as part of the Control/Structure Interaction (CSI) program at JPL. The focus of CSI activity at JPL is to develop the technology necessary to accurately control both the shape and vibration levels in the precision structures from which proposed large space-based observatories will be built. Structural error budgets for these types of structures will likely be in the sub-micron regime; optical tolerances will be even tighter. In order to achieve system level stability and local positioning at this level, it is generally expected that some form of active control will be required.

  11. Experimental and simulated control of lift using trailing edge devices

    NASA Astrophysics Data System (ADS)

    Cooperman, A.; Blaylock, M.; van Dam, C. P.

    2014-12-01

    Two active aerodynamic load control (AALC) devices coupled with a control algorithm are shown to decrease the change in lift force experienced by an airfoil during a change in freestream velocity. Microtabs are small (1% chord) surfaces deployed perpendicular to an airfoil, while microjets are pneumatic jets with flow perpendicular to the surface of the airfoil near the trailing edge. Both devices are capable of producing a rapid change in an airfoil's lift coefficient. A control algorithm for microtabs has been tested in a wind tunnel using a modified S819 airfoil, and a microjet control algorithm has been simulated for a NACA 0012 airfoil using OVERFLOW. In both cases, the AALC devices have shown the ability to mitigate the changes in lift during a gust.

  12. Experimental investigation of an accelerometer controlled automatic braking system

    NASA Technical Reports Server (NTRS)

    Dreher, R. C.; Sleeper, R. K.; Nayadley, J. R., Sr.

    1972-01-01

    An investigation was made to determine the feasibility of an automatic braking system for arresting the motion of an airplane by sensing and controlling braked wheel decelerations. The system was tested on a rotating drum dynamometer by using an automotive tire, wheel, and disk-brake assembly under conditions which included two tire loadings, wet and dry surfaces, and a range of ground speeds up to 70 knots. The controlling parameters were the rates at which brake pressure was applied and released and the Command Deceleration Level which governed the wheel deceleration by controlling the brake operation. Limited tests were also made with the automatic braking system installed on a ground vehicle in an effort to provide a more realistic proof of its feasibility. The results of this investigation indicate that a braking system which utilizes wheel decelerations as the control variable to restrict tire slip is feasible and capable of adapting to rapidly changing surface conditions.

  13. Control of experimental uncertainties in filtered Rayleigh scattering measurements

    NASA Technical Reports Server (NTRS)

    Forkey, Joseph N.; Finkelstein, N. D.; Lempert, Walter R.; Miles, Richard B.

    1995-01-01

    Filtered Rayleigh Scattering is a technique which allows for measurement of velocity, temperature, and pressure in unseeded flows, spatially resolved in 2-dimensions. We present an overview of the major components of a Filtered Rayleigh Scattering system. In particular, we develop and discuss a detailed theoretical model along with associated model parameters and related uncertainties. Based on this model, we then present experimental results for ambient room air and for a Mach 2 free jet, including spatially resolved measurements of velocity, temperature, and pressure.

  14. Revealing Student Thinking about Experimental Design and the Roles of Control Experiments

    ERIC Educational Resources Information Center

    Shi, Jia; Power, Joy M.; Klymkowsky, Michael W.

    2011-01-01

    Well-designed "controls" distinguish experimental from non-experimental studies. Surprisingly, we found that a high percentage of students had difficulty identifying control experiments even after completing three university-level laboratory courses. To address this issue, we designed and ran a revised cell biology lab course in which…

  15. Publishing Single-Case Research Design Studies That Do Not Demonstrate Experimental Control

    ERIC Educational Resources Information Center

    Tincani, Matt; Travers, Jason

    2018-01-01

    Demonstration of experimental control is considered a hallmark of high-quality single-case research design (SCRD). Studies that fail to demonstrate experimental control may not be published because researchers are unwilling to submit these papers for publication and journals are unlikely to publish negative results (i.e., the file drawer effect).…

  16. Four experimental demonstrations of active vibration control for flexible structures

    NASA Technical Reports Server (NTRS)

    Phillips, Doug; Collins, Emmanuel G., Jr.

    1990-01-01

    Laboratory experiments designed to test prototype active-vibration-control systems under development for future flexible space structures are described, summarizing previously reported results. The control-synthesis technique employed for all four experiments was the maximum-entropy optimal-projection (MEOP) method (Bernstein and Hyland, 1988). Consideration is given to: (1) a pendulum experiment on large-amplitude LF dynamics; (2) a plate experiment on broadband vibration suppression in a two-dimensional structure; (3) a multiple-hexagon experiment combining the factors studied in (1) and (2) to simulate the complexity of a large space structure; and (4) the NASA Marshall ACES experiment on a lightweight deployable 45-foot beam. Extensive diagrams, drawings, graphs, and photographs are included. The results are shown to validate the MEOP design approach, demonstrating that good performance is achievable using relatively simple low-order decentralized controllers.

  17. Experimental Investigations of Generalized Predictive Control for Tiltrotor Stability Augmentation

    NASA Technical Reports Server (NTRS)

    Nixon, Mark W.; Langston, Chester W.; Singleton, Jeffrey D.; Piatak, David J.; Kvaternik, Raymond G.; Bennett, Richard L.; Brown, Ross K.

    2001-01-01

    A team of researchers from the Army Research Laboratory, NASA Langley Research Center (LaRC), and Bell Helicopter-Textron, Inc. have completed hover-cell and wind-tunnel testing of a 1/5-size aeroelastically-scaled tiltrotor model using a new active control system for stability augmentation. The active system is based on a generalized predictive control (GPC) algorithm originally developed at NASA LaRC in 1997 for un-known disturbance rejection. Results of these investigations show that GPC combined with an active swashplate can significantly augment the damping and stability of tiltrotors in both hover and high-speed flight.

  18. GEOMORPHOLOGY. Experimental evidence for hillslope control of landscape scale.

    PubMed

    Sweeney, K E; Roering, J J; Ellis, C

    2015-07-03

    Landscape evolution theory suggests that climate sets the scale of landscape dissection by modulating the competition between diffusive processes that sculpt convex hillslopes and advective processes that carve concave valleys. However, the link between the relative dominance of hillslope and valley transport processes and landscape scale is difficult to demonstrate in natural landscapes due to the episodic nature of erosion. Here, we report results from laboratory experiments combining diffusive and advective processes in an eroding landscape. We demonstrate that rainsplash-driven disturbances in our experiments are a robust proxy for hillslope transport, such that increasing hillslope transport efficiency decreases drainage density. Our experimental results demonstrate how the coupling of climate-driven hillslope- and valley-forming processes, such as bioturbation and runoff, dictates the scale of eroding landscapes. Copyright © 2015, American Association for the Advancement of Science.

  19. Experimental herbicidal control of Dwarfmistletoe on some California conifers

    Treesearch

    Clarence R. Quick

    1964-01-01

    Dwarfmistletoes (Arceuthobium spp. ) parasitize and damage most native conifers of California. The study of chemical control for dwarfmistletoe on pines and true firs was resumed in 1959. Over the past 5 years, 246 tests on 2, 516 trees of five species have been started, Many phenoxy herbicides and some other materials were applied as sprays in fuel...

  20. Mathematical modeling of control system for the experimental steam generator

    NASA Astrophysics Data System (ADS)

    Podlasek, Szymon; Lalik, Krzysztof; Filipowicz, Mariusz; Sornek, Krzysztof; Kupski, Robert; Raś, Anita

    2016-03-01

    A steam generator is an essential unit of each cogeneration system using steam machines. Currently one of the cheapest ways of the steam generation can be application of old steam generators came from army surplus store. They have relatively simple construction and in case of not so exploited units - quite good general conditions, and functionality of mechanical components. By contrast, electrical components and control systems (mostly based on relay automatics) are definitely obsolete. It is not possible to use such units with cooperation of steam bus or with steam engines. In particular, there is no possibility for automatically adjustment of the pressure and the temperature of the generated steam supplying steam engines. Such adjustment is necessary in case of variation of a generator load. The paper is devoted to description of improvement of an exemplary unit together with construction of the measurement-control system based on a PLC. The aim was to enable for communication between the steam generator and controllers of the steam bus and steam engines in order to construction of a complete, fully autonomic and maintenance-free microcogeneration system.

  1. Beyond discounting: possible experimental models of impulse control.

    PubMed

    Monterosso, J; Ainslie, G

    1999-10-01

    Animal studies of impulsivity have typically used one of three models: a delay of reward procedure, a differential reinforcement for low rate responding (DRL) procedure, or an autoshaping procedure. In each of these paradigms, we argue, measurement of impulsivity is implicitly or explicitly equated with the effect delay has on the value of reward. The steepness by which delay diminishes value (the temporal discount function) is treated as an index of impulsivity. In order to provide a better analog of human impulsivity, this model needs to be expanded to include the converse of impulsivity - self-control. Through mechanisms such as committing to long range interests before the onset of temptation, or through bundling individual choices into classes of choices that are made at once, human decision-making can often look far less myopic than single trial experiments predict. For people, impulsive behavior may be more often the result of the breakdown of self-control mechanisms than of steep discount functions. Existing animal models of self-control are discussed, and future directions are suggested for psychopharmacological research.

  2. An experimental study of icing control using DBD plasma actuator

    NASA Astrophysics Data System (ADS)

    Cai, Jinsheng; Tian, Yongqiang; Meng, Xuanshi; Han, Xuzhao; Zhang, Duo; Hu, Haiyang

    2017-08-01

    Ice accretion on aircraft or wind turbine has been widely recognized as a big safety threat in the past decades. This study aims to develop a new approach for icing control using an AC-DBD plasma actuator. The experiments of icing control (i.e., anti-/de-icing) on a cylinder model were conducted in an icing wind tunnel with controlled wind speed (i.e., 15 m/s) and temperature (i.e., -10°C). A digital camera was used to record the dynamic processes of plasma anti-icing and de-icing whilst an infrared imaging system was utilized to map the surface temperature variations during the anti-/de-icing processes. It was found that the AC-DBD plasma actuator is very effective in both anti-icing and de-icing operations. While no ice formation was observed when the plasma actuator served as an anti-icing device, a complete removal of the ice layer with a thickness of 5 mm was achieved by activating the plasma actuator for ˜150 s. Such information demonstrated the feasibility of plasma anti-/de-icing, which could potentially provide more effective and safer icing mitigation strategies.

  3. Acceleration and torque feedback for robotic control - Experimental results

    NASA Technical Reports Server (NTRS)

    Mclnroy, John E.; Saridis, George N.

    1990-01-01

    Gross motion control of robotic manipulators typically requires significant on-line computations to compensate for nonlinear dynamics due to gravity, Coriolis, centripetal, and friction nonlinearities. One controller proposed by Luo and Saridis avoids these computations by feeding back joint acceleration and torque. This study implements the controller on a Puma 600 robotic manipulator. Joint acceleration measurement is obtained by measuring linear accelerations of each joint, and deriving a computationally efficient transformation from the linear measurements to the angular accelerations. Torque feedback is obtained by using the previous torque sent to the joints. The implementation has stability problems on the Puma 600 due to the extremely high gains inherent in the feedback structure. Since these high gains excite frequency modes in the Puma 600, the algorithm is modified to decrease the gain inherent in the feedback structure. The resulting compensator is stable and insensitive to high frequency unmodeled dynamics. Moreover, a second compensator is proposed which uses acceleration and torque feedback, but still allows nonlinear terms to be fed forward. Thus, by feeding the increment in the easily calculated gravity terms forward, improved responses are obtained. Both proposed compensators are implemented, and the real time results are compared to those obtained with the computed torque algorithm.

  4. Development and Experimental Evaluation of Passive Fuel Cell Thermal Control

    NASA Technical Reports Server (NTRS)

    Colozza, Anthony J.; Jakupca, Ian J.; Castle, Charles H.; Burke, Kenneth A.

    2014-01-01

    To provide uniform cooling for a fuel cell stack, a cooling plate concept was evaluated. This concept utilized thin cooling plates to extract heat from the interior of a fuel cell stack and move this heat to a cooling manifold where it can be transferred to an external cooling fluid. The advantages of this cooling approach include a reduced number of ancillary components and the ability to directly utilize an external cooling fluid loop for cooling the fuel cell stack. A number of different types of cooling plates and manifolds were developed. The cooling plates consisted of two main types; a plate based on thermopyrolytic graphite (TPG) and a planar (or flat plate) heat pipe. The plates, along with solid metal control samples, were tested for both thermal and electrical conductivity. To transfer heat from the cooling plates to the cooling fluid, a number of manifold designs utilizing various materials were devised, constructed, and tested. A key aspect of the manifold was that it had to be electrically nonconductive so it would not short out the fuel cell stack during operation. Different manifold and cooling plate configurations were tested in a vacuum chamber to minimize convective heat losses. Cooling plates were placed in the grooves within the manifolds and heated with surface-mounted electric pad heaters. The plate temperature and its thermal distribution were recorded for all tested combinations of manifold cooling flow rates and heater power loads. This testing simulated the performance of the cooling plates and manifold within an operational fuel cell stack. Different types of control valves and control schemes were tested and evaluated based on their ability to maintain a constant temperature of the cooling plates. The control valves regulated the cooling fluid flow through the manifold, thereby controlling the heat flow to the cooling fluid. Through this work, a cooling plate and manifold system was developed that could maintain the cooling plates

  5. [Muscular control of scapholunate instability. An experimental study].

    PubMed

    León-López, M M; García-Elías, M; Salvà-Coll, G; Llusá-Perez, M; Lluch-Bergadà, A

    2014-01-01

    As long as the neuromuscular stabilizers are intact, a lesion of the scapholunate ligament may or may not progress to a carpal instability. The mechanisms by which the muscles compensate this defect are not very well known. We designed an experimental study with the aim of clarifying these mechanisms. Using 10 fresh wrists, with no pre-existing lesions, we studied the movements of the scaphoid, triquetrum and capitate produced by the isometrical loading of the muscles which move the wrist, each of them isolated or combined, before and after cutting off the scapholunate ligaments. To do this, we placed sensors in each of these bones and used the Fastrack system to record these movements. The simultaneous loading of the muscles of the wrist produce rotational movements in flexion and supination of the proximal carpal row. After cutting off the scapholunate ligaments, the scaphoid rotates in pronation and flexion, while the triquetrum rotates in pronation and extension. In this situation of a scapholunate lesion, the muscles that worsen the carpal dexasation are the extensor carpi ulnaris and flexor carpi ulnaris. On the other hand, the isolated loading of the radial muscles reduce the scapholunate diastasis, thus improving the carpal alignment. In dynamic scapholunate instabilities, isometric contraction of the ulnar carpal muscles must be avoided, as it promotes the scapholunate diastasis. The rest of the muscles have the opposite effect, stabilizing the carpus when primary stabilizers have failed. Copyright © 2013 SECOT. Published by Elsevier Espana. All rights reserved.

  6. Experimental control and characterization of autophagy in Drosophila.

    PubMed

    Juhasz, Gabor; Neufeld, Thomas P

    2008-01-01

    Insects such as the fruit fly Drosophila melanogaster, which fundamentally reorganize their body plan during metamorphosis, make extensive use of autophagy for their normal development and physiology. In the fruit fly, the hepatic/adipose organ known as the fat body accumulates nutrient stores during the larval feeding stage. Upon entering metamorphosis, as well as in response to starvation, these nutrients are mobilized through a massive induction of autophagy, providing support to other tissues and organs during periods of nutrient deprivation. High levels of autophagy are also observed in larval tissues destined for elimination, such as the salivary glands and larval gut. Drosophila is emerging as an important system for studying the functions and regulation of autophagy in an in vivo setting. In this chapter we describe reagents and methods for monitoring autophagy in Drosophila, focusing on the larval fat body. We also describe methods for experimentally activating and inhibiting autophagy in this system and discuss the potential for genetic analysis in Drosophila to identify novel genes involved in autophagy.

  7. Experimental testing of spray dryer for control of incineration emissions.

    PubMed

    Wey, M Y; Wu, H Y; Tseng, H H; Chen, J C

    2003-05-01

    The research investigated the absorption/adsorption efficiency of sulfur dioxide (SO2), heavy metals, and polycyclic aromatic hydrocarbons (PAHs) with different Ca-based sorbents in a spray dryer during incineration process. For further improving the adsorption capacity of Ca-based sorbents, different spraying pressure and additives were carried out in this study. Experimental results showed that CaO could be used as an alternative sorbent in the spray dryer at an optimal initial particle size distribution of spraying droplet. In the spray dryer, Ca-based sorbents provided a lot of sites for heavy metals and PAHs condensing and calcium and alkalinity to react with metals to form merged species. As a result, heavy metals and PAHs could be removed from the flue gas simultaneously by condensation and adsorption. The additions of additives NaHCO3, SiO2, and KMnO4 were also found to be effective in improving the removal efficiency of these air pollutants.

  8. Heat defense control in an experimental heat disorder

    NASA Astrophysics Data System (ADS)

    Romanovsky, A. A.; Blatteis, C. M.

    Both whole-body heat exposure and intraperitoneal heating (IPH) result in a body temperature (Tb) fall that occurs once heating is abated (''hyperthermia- induced hypothermia''). This phenomenon involves a decrease in the threshold Tb (Tb-thresh) for activation of metabolic heat production (cold defense). Whether the Tb-thresh for ear skin vasodilation (heat defense) also changes during hyperthermia-induced hypothermia remains unknown. In experiment 1, we applied IPH to guinea pigs by perfusing water through a preimplanted intraperitoneal thermode and delivered the total heat load of either approximately 1.5 kJ (''short'' IPH; perfusion duration: 14 min) or approximately 3.0 kJ (''long'' IPH; 40 min). Short IPH caused skin vasodilation and a 1.1°C rise in Tb; no hypothermia occurred when IPH ceased. Long IPH caused vasodilation and hyperthermia of a comparable magnitude (1.4°C) that were followed by a Tb fall to 1.9°C below the preheating value. In experiment 2, the Tb-thresh for skin vasodilation was measured twice: at the beginning of long IPH and at the nadir of the post-IPH hypothermia. The two Tb-thresh values were 39.0 (SEM 0.1)°C and 39.2 (SEM 0.2)°C respectively. In the controls, the Tb-thresh was measured at the beginning and after short IPH; both control values were 39.0 (SEM 0.2)°C. We conclude that the hyperthermia- induced hypothermia, although previously shown to be coupled with a decrease in the Tb-thresh for cold defense, occurs without any substantial change in the Tb-thresh for heat defense. We speculate that postheating thermoregulatory disorders are associated with threshold dissociation, thus representing the poikilothermic (wide dead-band) type of Tb control.

  9. Circulation Control Model Experimental Database for CFD Validation

    NASA Technical Reports Server (NTRS)

    Paschal, Keith B.; Neuhart, Danny H.; Beeler, George B.; Allan, Brian G.

    2012-01-01

    A 2D circulation control wing was tested in the Basic Aerodynamic Research Tunnel at the NASA Langley Research Center. A traditional circulation control wing employs tangential blowing along the span over a trailing-edge Coanda surface for the purpose of lift augmentation. This model has been tested extensively at the Georgia Tech Research Institute for the purpose of performance documentation at various blowing rates. The current study seeks to expand on the previous work by documenting additional flow-field data needed for validation of computational fluid dynamics. Two jet momentum coefficients were tested during this entry: 0.047 and 0.114. Boundary-layer transition was investigated and turbulent boundary layers were established on both the upper and lower surfaces of the model. Chordwise and spanwise pressure measurements were made, and tunnel sidewall pressure footprints were documented. Laser Doppler Velocimetry measurements were made on both the upper and lower surface of the model at two chordwise locations (x/c = 0.8 and 0.9) to document the state of the boundary layers near the spanwise blowing slot.

  10. Experimental study on direct adaptive control of a PUMA 560 industrial robot

    NASA Technical Reports Server (NTRS)

    Seraji, H.; Lee, T.; Delpech, M.

    1990-01-01

    The implementation and experimental validation of a direct adaptive control scheme on a PUMA 560 industrial robot is discussed. The design theory for direct adaptive control of manipulators is outlined and the test facility and software are described. Results are presented from the experiments on the simultaneous control of all of the six joint angles and control of the end-effector position and orientation of the robot. Also, the possible applications of the direct adaptive control scheme are considered.

  11. Experimental Investigation of Actuators for Flow Control in Inlet Ducts

    NASA Astrophysics Data System (ADS)

    Vaccaro, John; Elimelech, Yossef; Amitay, Michael

    2010-11-01

    Attractive to aircraft designers are compact inlets, which implement curved flow paths to the compressor face. These curved flow paths could be employed for multiple reasons. One of which is to connect the air intake to the engine embedded in the aircraft body. A compromise must be made between the compactness of the inlet and its aerodynamic performance. The aerodynamic purpose of inlets is to decelerate the oncoming flow before reaching the engine while minimizing total pressure loss, unsteadiness and distortion. Low length-to-diameter ratio inlets have a high degree of curvature, which inevitably causes flow separation and secondary flows. Currently, the length of the propulsion system is constraining the overall size of Unmanned Air Vehicles (UAVs), thus, smaller more efficient aircrafts could be realized if the propulsion system could be shortened. Therefore, active flow control is studied in a compact (L/D=1.5) inlet to improve performance metrics. Actuation from a spanwise varying coanda type ejector actuator and a hybrid coanda type ejector / vortex generator jet actuator is investigated. Special attention will be given to the pressure recovery at the AIP along with unsteady pressure signatures along the inlet surface and at the AIP.

  12. Generation of Quality Pulses for Control of Qubit/Quantum Memory Spin States: Experimental and Simulation

    DTIC Science & Technology

    2016-09-01

    TECHNICAL REPORT 3046 September 2016 GENERATION OF QUALITY PULSES FOR CONTROL OF QUBIT/QUANTUM MEMORY SPIN STATES: EXPERIMENTAL AND SIMULATION...control circuitry for control of electron/ nuclear spin states of qubits/quantum memory applicable to semiconductor, superconductor, ionic, and...coherence time of the qubit/ memory , we present as an example the integration of cryogenic superconductor components, including filters and

  13. On the Reporting of Experimental and Control Therapies in Stroke Rehabilitation Trials: A Systematic Review.

    PubMed

    Lohse, Keith R; Pathania, Anupriya; Wegman, Rebecca; Boyd, Lara A; Lang, Catherine E

    2018-03-01

    To use the Centralized Open-Access Rehabilitation database for Stroke to explore reporting of both experimental and control interventions in randomized controlled trials for stroke rehabilitation (including upper and lower extremity therapies). The Centralized Open-Access Rehabilitation database for Stroke was created from a search of MEDLINE, Embase, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, and Cumulative Index of Nursing and Allied Health from the earliest available date to May 31, 2014. A total of 2892 titles were reduced to 514 that were screened by full text. This screening left 215 randomized controlled trials in the database (489 independent groups representing 12,847 patients). Using a mixture of qualitative and quantitative methods, we performed a text-based analysis of how the procedures of experimental and control therapies were described. Experimental and control groups were rated by 2 independent coders according to the Template for Intervention Description and Replication criteria. Linear mixed-effects regression with a random effect of study (groups nested within studies) showed that experimental groups had statistically more words in their procedures (mean, 271.8 words) than did control groups (mean, 154.8 words) (P<.001). Experimental groups had statistically more references in their procedures (mean, 1.60 references) than did control groups (mean, .82 references) (P<.001). Experimental groups also scored significantly higher on the total Template for Intervention Description and Replication checklist (mean score, 7.43 points) than did control groups (mean score, 5.23 points) (P<.001). Control treatments in stroke motor rehabilitation trials are underdescribed relative to experimental treatments. These poor descriptions are especially problematic for "conventional" therapy control groups. Poor reporting is a threat to the internal validity and generalizability of clinical trial results. We recommend

  14. A quasi-experimental study on the effects of instrument assisted soft tissue mobilization on mechanosensitive neurons.

    PubMed

    Ge, Weiqing; Roth, Emily; Sansone, Alyssa

    2017-04-01

    [Purpose] Instrument Assisted Soft Tissue Mobilization (IASTM) is a form of manual therapy. Despite its growing popularity and an increasing number of patients receiving IASTM each year, there is a lack of high-level evidence to elucidate its therapeutic mechanisms and to support its clinical applications. The purpose of this research project was to determine the effects of IASTM on activities of mechanosensitive neurons in skin. [Subjects and Methods] Twenty-three subjects, 9 females and 14 males, mean age 25.7 (SD 6.4) years old were recruited through a convenience sampling on the university campus. The study design was a quasi-experimental study using single group pretest-posttest design. The activities of mechanosensitive neurons were measured before and after the application of IASTM. [Results] The mean 2-point discrimination was 40.2 (SD 9.4) mm before IASTM and increased to 44.9 (SD 12.0) mm after IASTM. The increase was statistically significant pre and post IASTM. The mean pain threshold was 18.2 (SD 6.6) lb and increased slightly to 18.7 (SD 6.8) lb after IASTM; however, no statistical significance was found pre and post IASTM. [Conclusion] The data indicates that IASTM changes the neural activities in 2-point discrimination but not in pain threshold.

  15. A Human-Centered Command and Control (C2) Assessment of an Experimental Campaign Planning Tool

    DTIC Science & Technology

    2014-04-01

    and control (team without the CPT) groups . The two groups were designed to have an equal number of members; however, one member of the experimental...the researchers to analyze the planning process and outcomes. 3.3 Design and Procedure An experimental versus control group design was implemented...the post -PFnet (figure 16b). Within the PFnets, a concept can be focused on in order to identify how the individual or group is defining or

  16. Design and experimental evaluation of robust controllers for a two-wheeled robot

    NASA Astrophysics Data System (ADS)

    Kralev, J.; Slavov, Ts.; Petkov, P.

    2016-11-01

    The paper presents the design and experimental evaluation of two alternative μ-controllers for robust vertical stabilisation of a two-wheeled self-balancing robot. The controllers design is based on models derived by identification from closed-loop experimental data. In the first design, a signal-based uncertainty representation obtained directly from the identification procedure is used, which leads to a controller of order 29. In the second design the signal uncertainty is approximated by an input multiplicative uncertainty, which leads to a controller of order 50, subsequently reduced to 30. The performance of the two μ-controllers is compared with the performance of a conventional linear quadratic controller with 17th-order Kalman filter. A proportional-integral controller of the rotational motion around the vertical axis is implemented as well. The control code is generated using Simulink® controller models and is embedded in a digital signal processor. Results from the simulation of the closed-loop system as well as experimental results obtained during the real-time implementation of the designed controllers are given. The theoretical investigation and experimental results confirm that the closed-loop system achieves robust performance in respect to the uncertainties related to the identified robot model.

  17. Experimental verification of rank 1 chaos in switch-controlled Chua circuit.

    PubMed

    Oksasoglu, Ali; Ozoguz, Serdar; Demirkol, Ahmet S; Akgul, Tayfun; Wang, Qiudong

    2009-03-01

    In this paper, we provide the first experimental proof for the existence of rank 1 chaos in the switch-controlled Chua circuit by following a step-by-step procedure given by the theory of rank 1 maps. At the center of this procedure is a periodically kicked limit cycle obtained from the unforced system. Then, this limit cycle is subjected to periodic kicks by adding externally controlled switches to the original circuit. Both the smooth nonlinearity and the piecewise linear cases are considered in this experimental investigation. Experimental results are found to be in concordance with the conclusions of the theory.

  18. Anatomy of an experimental two-link flexible manipulator under end-point control

    NASA Technical Reports Server (NTRS)

    Oakley, Celia M.; Cannon, Robert H., Jr.

    1990-01-01

    The design and experimental implementation of an end-point controller for two-link flexible manipulators are presented. The end-point controller is based on linear quadratic Gaussian (LQG) theory and is shown to exhibit significant improvements in trajectory tracking over a conventional controller design. To understand the behavior of the manipulator structure under end-point control, a strobe sequence illustrating the link deflections during a typical slew maneuver is included.

  19. Reservoir sedimentation rates in the Little Washita River experimental watershed, Oklahoma: measurement and controlling factors

    USDA-ARS?s Scientific Manuscript database

    Forty-five flood control reservoirs, authorized in the United States Flood Control Act of 1936, were installed between 1969 and 1982 in the Little Washita River Experimental Watershed (LWREW), located in central Oklahoma. Over time, these reservoirs have lost water storage capacity due to sedimentat...

  20. Experimental Determination of Demand Response Control Models and Cost of Control for Ensembles of Window-Mount Air Conditioners

    SciTech Connect

    Geller, Drew Adam; Backhaus, Scott N.

    Control of consumer electrical devices for providing electrical grid services is expanding in both the scope and the diversity of loads that are engaged in control, but there are few experimentally-based models of these devices suitable for control designs and for assessing the cost of control. A laboratory-scale test system is developed to experimentally evaluate the use of a simple window-mount air conditioner for electrical grid regulation services. The experimental test bed is a single, isolated air conditioner embedded in a test system that both emulates the thermodynamics of an air conditioned room and also isolates the air conditioner frommore » the real-world external environmental and human variables that perturb the careful measurements required to capture a model that fully characterizes both the control response functions and the cost of control. The control response functions and cost of control are measured using harmonic perturbation of the temperature set point and a test protocol that further isolates the air conditioner from low frequency environmental variability.« less

  1. Experimental and numerical investigation of a phase-only control mechanism in the linear intensity regime.

    PubMed

    Brühl, Elisabeth; Buckup, Tiago; Motzkus, Marcus

    2018-06-07

    Mechanisms and optimal experimental conditions in coherent control still intensely stimulate debates. In this work, a phase-only control mechanism in an open quantum system is investigated experimentally and numerically. Several parameterizations for femtosecond pulse shaping (combination of chirp and multipulses) are exploited in transient absorption of a prototype organic molecule to control population and vibrational coherence in ground and excited states. Experimental results are further numerically simulated and corroborated with a four-level density-matrix model, which reveals a phase-only control mechanism based on the interaction between the tailored phase of the excitation pulse and the induced transient absorption. In spite of performing experiment and numerical simulations in the linear regime of excitation, the control effect amplitude depends non-linearly on the excitation energy and is explained as a pump-dump control mechanism. No evidence of single-photon control is observed with the model. Moreover, our results also show that the control effect on the population and vibrational coherence is highly dependent on the spectral detuning of the excitation spectrum. Contrary to the popular belief in coherent control experiments, spectrally resonant tailored excitation will lead to the control of the excited state only for very specific conditions.

  2. Experimental evaluation of HJB optimal controllers for the attitude dynamics of a multirotor aerial vehicle.

    PubMed

    Prado, Igor Afonso Acampora; Pereira, Mateus de Freitas Virgílio; de Castro, Davi Ferreira; Dos Santos, Davi Antônio; Balthazar, Jose Manoel

    2018-06-01

    The present paper is concerned with the design and experimental evaluation of optimal control laws for the nonlinear attitude dynamics of a multirotor aerial vehicle. Three design methods based on Hamilton-Jacobi-Bellman equation are taken into account. The first one is a linear control with guarantee of stability for nonlinear systems. The second and third are a nonlinear suboptimal control techniques. These techniques are based on an optimal control design approach that takes into account the nonlinearities present in the vehicle dynamics. The stability Proof of the closed-loop system is presented. The performance of the control system designed is evaluated via simulations and also via an experimental scheme using the Quanser 3-DOF Hover. The experiments show the effectiveness of the linear control method over the nonlinear strategy. Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.

  3. Effects of leisure education on self-rated health among older adults.

    PubMed

    Chang, Liang-Chih; Yu, Ping; Jeng, Mei-Yuan

    2015-01-01

    This study examined whether a leisure education program could promote leisure autonomy and self-rated health (SRH) among older adults. A pretest-posttest randomized experimental design was conducted. Subjects were randomly assigned to either an experimental group (n = 30) or a control group (n = 30). Data related to leisure autonomy and SRH were collected shortly before and after the experiment. Pretest and posttest data were analyzed using an analysis of covariance. The results indicated that the average posttest scores of leisure autonomy and SRH in the experimental group were significantly higher than those in the control group. Implications of the results are discussed.

  4. Experimental relevance of global properties of time-delayed feedback control.

    PubMed

    von Loewenich, Clemens; Benner, Hartmut; Just, Wolfram

    2004-10-22

    We show by means of theoretical considerations and electronic circuit experiments that time-delayed feedback control suffers from severe global constraints if transitions at the control boundaries are discontinuous. Subcritical behavior gives rise to small basins of attraction and thus limits the control performance. The reported properties are, on the one hand, universal since the mechanism is based on general arguments borrowed from bifurcation theory and, on the other hand, directly visible in experimental time series.

  5. Experimental study of tail-span effects on a generic canard-controlled missile

    NASA Technical Reports Server (NTRS)

    Blair, A. B., Jr.; Dillon, James L.; Watson, Carolyn B.

    1992-01-01

    An experimental investigation was conducted on a cruciform canard controlled missile configuration to determine the effects of tail span/canard span ratio on controllability. The investigation was conducted over the Mach number range of 1.75 to 3.50. Reductions of tail span/canard span ratio produced lower static margins and higher trim angle of attack. The results show that canard controls can provide pitch- and yaw-control as well as roll-control by proper selection of the tail span/canard span ratio.

  6. Effects of Video Game Training on Behavioral and Electrophysiological Measures of Attention and Memory: Protocol for a Randomized Controlled Trial.

    PubMed

    Ballesteros, Soledad; Mayas, Julia; Ruiz-Marquez, Eloisa; Prieto, Antonio; Toril, Pilar; Ponce de Leon, Laura; de Ceballos, Maria L; Reales Avilés, José Manuel

    2017-01-24

    Neuroplasticity-based approaches seem to offer promising ways of maintaining cognitive health in older adults and postponing the onset of cognitive decline symptoms. Although previous research suggests that training can produce transfer effects, this study was designed to overcome some limitations of previous studies by incorporating an active control group and the assessment of training expectations. The main objectives of this study are (1) to evaluate the effects of a randomized computer-based intervention consisting of training older adults with nonaction video games on brain and cognitive functions that decline with age, including attention and spatial working memory, using behavioral measures and electrophysiological recordings (event-related potentials [ERPs]) just after training and after a 6-month no-contact period; (2) to explore whether motivation, engagement, or expectations might account for possible training-related improvements; and (3) to examine whether inflammatory mechanisms assessed with noninvasive measurement of C-reactive protein in saliva impair cognitive training-induced effects. A better understanding of these mechanisms could elucidate pathways that could be targeted in the future by either behavioral or neuropsychological interventions. A single-blinded randomized controlled trial with an experimental group and an active control group, pretest, posttest, and 6-month follow-up repeated measures design is used in this study. A total of 75 cognitively healthy older adults were randomly distributed into experimental and active control groups. Participants in the experimental group received 16 1-hour training sessions with cognitive nonaction video games selected from Lumosity, a commercial brain training package. The active control group received the same number of training sessions with The Sims and SimCity, a simulation strategy game. We have recruited participants, have conducted the training protocol and pretest assessments, and are

  7. A support vector machine based control application to the experimental three-tank system.

    PubMed

    Iplikci, Serdar

    2010-07-01

    This paper presents a support vector machine (SVM) approach to generalized predictive control (GPC) of multiple-input multiple-output (MIMO) nonlinear systems. The possession of higher generalization potential and at the same time avoidance of getting stuck into the local minima have motivated us to employ SVM algorithms for modeling MIMO systems. Based on the SVM model, detailed and compact formulations for calculating predictions and gradient information, which are used in the computation of the optimal control action, are given in the paper. The proposed MIMO SVM-based GPC method has been verified on an experimental three-tank liquid level control system. Experimental results have shown that the proposed method can handle the control task successfully for different reference trajectories. Moreover, a detailed discussion on data gathering, model selection and effects of the control parameters have been given in this paper. 2010 ISA. Published by Elsevier Ltd. All rights reserved.

  8. Design and experimental validation of a flutter suppression controller for the active flexible wing

    NASA Technical Reports Server (NTRS)

    Waszak, Martin R.; Srinathkumar, S.

    1992-01-01

    The synthesis and experimental validation of an active flutter suppression controller for the Active Flexible Wing wind tunnel model is presented. The design is accomplished with traditional root locus and Nyquist methods using interactive computer graphics tools and extensive simulation based analysis. The design approach uses a fundamental understanding of the flutter mechanism to formulate a simple controller structure to meet stringent design specifications. Experimentally, the flutter suppression controller succeeded in simultaneous suppression of two flutter modes, significantly increasing the flutter dynamic pressure despite modeling errors in predicted flutter dynamic pressure and flutter frequency. The flutter suppression controller was also successfully operated in combination with another controller to perform flutter suppression during rapid rolling maneuvers.

  9. Flutter suppression for the Active Flexible Wing - Control system design and experimental validation

    NASA Technical Reports Server (NTRS)

    Waszak, M. R.; Srinathkumar, S.

    1992-01-01

    The synthesis and experimental validation of a control law for an active flutter suppression system for the Active Flexible Wing wind-tunnel model is presented. The design was accomplished with traditional root locus and Nyquist methods using interactive computer graphics tools and with extensive use of simulation-based analysis. The design approach relied on a fundamental understanding of the flutter mechanism to formulate understanding of the flutter mechanism to formulate a simple control law structure. Experimentally, the flutter suppression controller succeeded in simultaneous suppression of two flutter modes, significantly increasing the flutter dynamic pressure despite errors in the design model. The flutter suppression controller was also successfully operated in combination with a rolling maneuver controller to perform flutter suppression during rapid rolling maneuvers.

  10. Controls-structures interaction guest investigator program: Overview and phase 1 experimental results and future plans

    NASA Technical Reports Server (NTRS)

    Smith-Taylor, Rudeen; Tanner, Sharon E.

    1993-01-01

    The NASA Controls-Structures Interaction (CSI) Guest Investigator program is described in terms of its support of the development of CSI technologies. The program is based on the introduction of CSI researchers from industry and academia to available test facilities for experimental validation of technologies and methods. Phase 1 experimental results are reviewed with attention given to their use of the Mini-MAST test facility and the facility for the Advance Control Evaluation of Structures. Experiments were conducted regarding the following topics: collocated/noncollocated controllers, nonlinear math modeling, controller design, passive/active suspension systems design, and system identification and fault isolation. The results demonstrate that significantly enhanced performance from the control techniques can be achieved by integrating knowledge of the structural dynamics under consideration into the approaches.

  11. Shaking table experimentation on adjacent structures controlled by passive and semi-active MR dampers

    NASA Astrophysics Data System (ADS)

    Basili, M.; De Angelis, M.; Fraraccio, G.

    2013-06-01

    This paper presents the results of shaking table tests on adjacent structures controlled by passive and semi-active MR dampers. The aim was to demonstrate experimentally the effectiveness of passive and semi-active strategies in reducing structural vibrations due to seismic excitation. The physical model at issue was represented by two adjacent steel structures, respectively of 4 and 2 levels, connected at the second level by a MR damper. When the device operated in semi-active mode, an ON-OFF control algorithm, derived by the Lyapunov stability theory, was implemented and experimentally validated. Since the experimentation concerned adjacent structures, two control objectives have been reached: global and selective protection. In case of global protection, the attention was focused on protecting both structures, whereas, in case of selective protection, the attention was focused on protecting only one structure. For each objective the effectiveness of passive control has been compared with the situation of no control and then the effectiveness of semi-active control has been compared with the passive one. The quantities directly compared have been: measured displacements, accelerations and force-displacement of the MR damper, moreover some global response quantities have been estimated from experimental measures, which are the base share force and the base bending moment, the input energy and the energy dissipated by the device. In order to evaluate the effectiveness of the control action in both passive and semi-active case, an energy index EDI, previously defined and already often applied numerically, has been utilized. The aspects investigated in the experimentation have been: the implementation and validation of the control algorithm for selective and global protection, the MR damper input voltage influence, the kind of seismic input and its intensity.

  12. A Health Belief Model-Social Learning Theory approach to adolescents' fertility control: findings from a controlled field trial.

    PubMed

    Eisen, M; Zellman, G L; McAlister, A L

    1992-01-01

    We evaluated an 8- to 12-hour Health Belief Model-Social Learning Theory (HBM-SLT)-based sex education program against several community- and school-based interventions in a controlled field experiment. Data on sexual and contraceptive behavior were collected from 1,444 adolescents unselected for gender, race/ethnicity, or virginity status in a pretest-posttest design. Over 60% completed the one-year follow-up. Multivariate analyses were conducted separately for each preintervention virginity status by gender grouping. The results revealed differential program impacts. First, for preintervention virgins, there were no gender or intervention differences in abstinence maintenance over the follow-up year. Second, female preintervention Comparison program virgins used effective contraceptive methods more consistently than those who attended the HBM-SLT program (p less than 0.01); among males, the intervention programs were equally effective. Third, both interventions significantly increased contraceptive efficiency for teenagers who were sexually active before attending the programs. For males, the HBM-SLT program led to significantly greater follow-up contraceptive efficiency than the Comparison program with preintervention contraceptive efficiency controlled (p less than 0.05); for females, the programs produced equivalent improvement. Implications for program planning and evaluation are discussed.

  13. Design and experimental validation of linear and nonlinear vehicle steering control strategies

    NASA Astrophysics Data System (ADS)

    Menhour, Lghani; Lechner, Daniel; Charara, Ali

    2012-06-01

    This paper proposes the design of three control laws dedicated to vehicle steering control, two based on robust linear control strategies and one based on nonlinear control strategies, and presents a comparison between them. The two robust linear control laws (indirect and direct methods) are built around M linear bicycle models, each of these control laws is composed of two M proportional integral derivative (PID) controllers: one M PID controller to control the lateral deviation and the other M PID controller to control the vehicle yaw angle. The indirect control law method is designed using an oscillation method and a nonlinear optimisation subject to H ∞ constraint. The direct control law method is designed using a linear matrix inequality optimisation in order to achieve H ∞ performances. The nonlinear control method used for the correction of the lateral deviation is based on a continuous first-order sliding-mode controller. The different methods are designed using a linear bicycle vehicle model with variant parameters, but the aim is to simulate the nonlinear vehicle behaviour under high dynamic demands with a four-wheel vehicle model. These steering vehicle controls are validated experimentally using the data acquired using a laboratory vehicle, Peugeot 307, developed by National Institute for Transport and Safety Research - Department of Accident Mechanism Analysis Laboratory's (INRETS-MA) and their performance results are compared. Moreover, an unknown input sliding-mode observer is introduced to estimate the road bank angle.

  14. Evaluation of World Health Organization Multi-Professional Patient Safety Curriculum Topics in Nursing Education: Pre-test, post-test, none-experimental study.

    PubMed

    Mansour, Mansour; Skull, Alice; Parker, Michael

    2015-01-01

    The Multi-professional Patient Safety Curriculum Guide was launched by the World Health Organization to develop a patient safety-friendly curriculum in health education. The aim of this study was to evaluate the impact of teaching related to two topics from the Patient Safety Curriculum Guide on student nurses' knowledge and attitudes toward patient safety. A pretest, posttest, nonexperimental design was used. Patient safety education questionnaires were distributed to a convenience sample of 181 nursing students before the intervention, and 141 questionnaires after the intervention in one university in the East of England. The intervention consisted of two face-to-face lectures and one facilitated group work discussion. Seventy-one responses from pre- and posttest stages were matched. Paired t test, McNemar's test, and frequency measures were used for data analysis. The findings suggest that there are statistically significant differences in the subscales of the error and patient safety and personal influence over safety. The differences in the students' answers on patient safety knowledge before and after the interventions were not statistically significant. Although the student nurses highly commended the teaching delivered in this study, the use of experimental design in future curriculum evaluation may provide a more complementary insight to the findings of this study. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. Multidisciplinary Training on Spiritual Care for Patients in Palliative Care Trajectories Improves the Attitudes and Competencies of Hospital Medical Staff: Results of a Quasi-Experimental Study.

    PubMed

    van de Geer, Joep; Veeger, Nic; Groot, Marieke; Zock, Hetty; Leget, Carlo; Prins, Jelle; Vissers, Kris

    2018-02-01

    Patients value health-care professionals' attention to their spiritual needs. However, this is undervalued in health-care professionals' education. Additional training is essential for implementation of a national multidisciplinary guideline on spiritual care (SC) in palliative care (PC). Aim of this study is to measure effects of a training program on SC in PC based on the guideline. A pragmatic multicenter trial using a quasi-experimental pretest-posttest design as part of an action research study. Eight multidisciplinary teams in regular wards and 1 team of PC consultants, in 8 Dutch teaching hospitals, received questionnaires before training about perceived barriers for SC, spiritual attitudes and involvement, and SC competencies. The effect on the barriers on SC and SC competencies were measured both 1 and 6 months after the training. For nurses (n = 214), 7 of 8 barriers to SC were decreased after 1 month, but only 2 were still after 6 months. For physicians (n = 41), the training had no effect on the barriers to SC. Nurses improved in 4 of 6 competencies after both 1 and 6 months. Physicians improved in 3 of 6 competencies after 1 month but in only 1 competency after 6 months. Concise SC training programs for clinical teams can effect quality of care, by improving hospital staff competencies and decreasing the barriers they perceive. Differences in the effects of the SC training on nurses and physicians show the need for further research on physicians' educational needs on SC.

  16. Theoretical and experimental aspects of chaos control by time-delayed feedback.

    PubMed

    Just, Wolfram; Benner, Hartmut; Reibold, Ekkehard

    2003-03-01

    We review recent developments for the control of chaos by time-delayed feedback methods. While such methods are easily applied even in quite complex experimental context the theoretical analysis yields infinite-dimensional differential-difference systems which are hard to tackle. The essential ideas for a general theoretical approach are sketched and the results are compared to electronic circuits and to high power ferromagnetic resonance experiments. Our results show that the control performance can be understood on the basis of experimentally accessible quantities without resort to any model for the internal dynamics.

  17. Experimental verification of the flow characteristics of an active controlled microfluidic valve with annular boundary

    NASA Astrophysics Data System (ADS)

    Pan, Chun-Peng; Wang, Dai-Hua

    2014-03-01

    The principle and structural configuration of an active controlled microfluidic valve with annular boundary is presented in this paper. The active controlled flowrate model of the active controlled microfluidic valve with annular boundary is established. The prototypes of the active controlled microfluidic valves with annular boundaries with three different combinations of the inner and outer radii are fabricated and tested on the established experimental setup. The experimental results show that: (1) The active controlled microfluidic valve with annular boundary possesses the on/off switching and the continuous control capability of the fluid with simple structure and easy fabrication processing; (2) When the inner and outer diameters of the annular boundary are 1.5 mm and 3.5 mm, respectively, the maximum flowrate of the valve is 0.14 ml/s when the differential pressure of the inlet and outlet of the valve is 1000 Pa and the voltage applied to circular piezoelectric unimorph actuator is 100 V; (3) The established active controlled flowrate model can accurately predict the controlled flowrate of the active controlled microfluidic valves with the maximum relative error of 6.7%. The results presented in this paper lay the foundation for designing and developing the active controlled microfluidic valves with annular boundary driven by circular piezoelectric unimorph actuators.

  18. The experimental identification of magnetorheological dampers and evaluation of their controllers

    NASA Astrophysics Data System (ADS)

    Metered, H.; Bonello, P.; Oyadiji, S. O.

    2010-05-01

    Magnetorheological (MR) fluid dampers are semi-active control devices that have been applied over a wide range of practical vibration control applications. This paper concerns the experimental identification of the dynamic behaviour of an MR damper and the use of the identified parameters in the control of such a damper. Feed-forward and recurrent neural networks are used to model both the direct and inverse dynamics of the damper. Training and validation of the proposed neural networks are achieved by using the data generated through dynamic tests with the damper mounted on a tensile testing machine. The validation test results clearly show that the proposed neural networks can reliably represent both the direct and inverse dynamic behaviours of an MR damper. The effect of the cylinder's surface temperature on both the direct and inverse dynamics of the damper is studied, and the neural network model is shown to be reasonably robust against significant temperature variation. The inverse recurrent neural network model is introduced as a damper controller and experimentally evaluated against alternative controllers proposed in the literature. The results reveal that the neural-based damper controller offers superior damper control. This observation and the added advantages of low-power requirement, extended service life of the damper and the minimal use of sensors, indicate that a neural-based damper controller potentially offers the most cost-effective vibration control solution among the controllers investigated.

  19. A combined-slip predictive control of vehicle stability with experimental verification

    NASA Astrophysics Data System (ADS)

    Jalali, Milad; Hashemi, Ehsan; Khajepour, Amir; Chen, Shih-ken; Litkouhi, Bakhtiar

    2018-02-01

    In this paper, a model predictive vehicle stability controller is designed based on a combined-slip LuGre tyre model. Variations in the lateral tyre forces due to changes in tyre slip ratios are considered in the prediction model of the controller. It is observed that the proposed combined-slip controller takes advantage of the more accurate tyre model and can adjust tyre slip ratios based on lateral forces of the front axle. This results in an interesting closed-loop response that challenges the notion of braking only the wheels on one side of the vehicle in differential braking. The performance of the proposed controller is evaluated in software simulations and is compared to a similar pure-slip controller. Furthermore, experimental tests are conducted on a rear-wheel drive electric Chevrolet Equinox equipped with differential brakes to evaluate the closed-loop response of the model predictive control controller.

  20. Experimental Comparison of two Active Vibration Control Approaches: Velocity Feedback and Negative Capacitance Shunt Damping

    NASA Technical Reports Server (NTRS)

    Beck, Benjamin; Schiller, Noah

    2013-01-01

    This paper outlines a direct, experimental comparison between two established active vibration control techniques. Active vibration control methods, many of which rely upon piezoelectric patches as actuators and/or sensors, have been widely studied, showing many advantages over passive techniques. However, few direct comparisons between different active vibration control methods have been made to determine the performance benefit of one method over another. For the comparison here, the first control method, velocity feedback, is implemented using four accelerometers that act as sensors along with an analog control circuit which drives a piezoelectric actuator. The second method, negative capacitance shunt damping, consists of a basic analog circuit which utilizes a single piezoelectric patch as both a sensor and actuator. Both of these control methods are implemented individually using the same piezoelectric actuator attached to a clamped Plexiglas window. To assess the performance of each control method, the spatially averaged velocity of the window is compared to an uncontrolled response.

  1. Management of geriatric incontinence in nursing homes.

    PubMed Central

    Schnelle, J F; Traughber, B; Morgan, D B; Embry, J E; Binion, A F; Coleman, A

    1983-01-01

    A behavioral management system designed to reduce urinary incontinence was evaluated in two nursing homes with a pretest-posttest control group design with repeated measures. The primary components of the system were prompting and contingent social approval/disapproval which required approximately 2.5 minutes per patient per hour to administer. The frequency of correct toileting for experimental subjects increased by approximately 45%. The experimental groups were significantly different from the control groups on both incontinence and correct toileting measures. The results are discussed in view of the management issues inherent in nursing home settings. PMID:6885672

  2. Experimental benchmarking of quantum control in zero-field nuclear magnetic resonance

    PubMed Central

    Feng, Guanru

    2018-01-01

    Demonstration of coherent control and characterization of the control fidelity is important for the development of quantum architectures such as nuclear magnetic resonance (NMR). We introduce an experimental approach to realize universal quantum control, and benchmarking thereof, in zero-field NMR, an analog of conventional high-field NMR that features less-constrained spin dynamics. We design a composite pulse technique for both arbitrary one-spin rotations and a two-spin controlled-not (CNOT) gate in a heteronuclear two-spin system at zero field, which experimentally demonstrates universal quantum control in such a system. Moreover, using quantum information–inspired randomized benchmarking and partial quantum process tomography, we evaluate the quality of the control, achieving single-spin control for 13C with an average fidelity of 0.9960(2) and two-spin control via a CNOT gate with a fidelity of 0.9877(2). Our method can also be extended to more general multispin heteronuclear systems at zero field. The realization of universal quantum control in zero-field NMR is important for quantum state/coherence preparation, pulse sequence design, and is an essential step toward applications to materials science, chemical analysis, and fundamental physics. PMID:29922714

  3. Experimental benchmarking of quantum control in zero-field nuclear magnetic resonance.

    PubMed

    Jiang, Min; Wu, Teng; Blanchard, John W; Feng, Guanru; Peng, Xinhua; Budker, Dmitry

    2018-06-01

    Demonstration of coherent control and characterization of the control fidelity is important for the development of quantum architectures such as nuclear magnetic resonance (NMR). We introduce an experimental approach to realize universal quantum control, and benchmarking thereof, in zero-field NMR, an analog of conventional high-field NMR that features less-constrained spin dynamics. We design a composite pulse technique for both arbitrary one-spin rotations and a two-spin controlled-not (CNOT) gate in a heteronuclear two-spin system at zero field, which experimentally demonstrates universal quantum control in such a system. Moreover, using quantum information-inspired randomized benchmarking and partial quantum process tomography, we evaluate the quality of the control, achieving single-spin control for 13 C with an average fidelity of 0.9960(2) and two-spin control via a CNOT gate with a fidelity of 0.9877(2). Our method can also be extended to more general multispin heteronuclear systems at zero field. The realization of universal quantum control in zero-field NMR is important for quantum state/coherence preparation, pulse sequence design, and is an essential step toward applications to materials science, chemical analysis, and fundamental physics.

  4. Sensitivity to Structure in the Speech Signal by Children with Speech Sound Disorder and Reading Disability

    ERIC Educational Resources Information Center

    Johnson, Erin Phinney; Pennington, Bruce F.; Lowenstein, Joanna H.; Nittrouer, Susan

    2011-01-01

    Research Design;Intervention;Biology;Biotechnology;Teaching Methods;Hands on Science;Professional Development;Comparative Analysis;Genetics;Evaluation;Pretests Posttests;Control Groups;Science Education;Science Instruction;Pedagogical Content Knowledge;

  5. Development and experimental design of a novel controlled-release matrix tablet formulation for indapamide hemihydrate.

    PubMed

    Antovska, Packa; Ugarkovic, Sonja; Petruševski, Gjorgji; Stefanova, Bosilka; Manchevska, Blagica; Petkovska, Rumenka; Makreski, Petre

    2017-11-01

    Development, experimental design and in vitro in vivo correlation (IVIVC) of controlled-release matrix formulation. Development of novel oral controlled delivery system for indapamide hemihydrate, optimization of the formulation by experimental design and evaluation regarding IVIVC on a pilot scale batch as a confirmation of a well-established formulation. In vitro dissolution profiles of controlled-release tablets of indapamide hemihydrate from four different matrices had been evaluated in comparison to the originator's product Natrilix (Servier) as a direction for further development and optimization of a hydroxyethylcellulose-based matrix controlled-release formulation. A central composite factorial design had been applied for the optimization of a chosen controlled-release tablet formulation. The controlled-release tablets with appropriate physical and technological properties had been obtained with a matrix: binder concentration variations in the range: 20-40w/w% for the matrix and 1-3w/w% for the binder. The experimental design had defined the design space for the formulation and was prerequisite for extraction of a particular formulation that would be a subject for transfer on pilot scale and IVIV correlation. The release model of the optimized formulation has shown best fit to the zero order kinetics depicted with the Hixson-Crowell erosion-dependent mechanism of release. Level A correlation was obtained.

  6. Experimental Study of Flexible Plate Vibration Control by Using Two-Loop Sliding Mode Control Strategy

    NASA Astrophysics Data System (ADS)

    Yang, Jingyu; Lin, Jiahui; Liu, Yuejun; Yang, Kang; Zhou, Lanwei; Chen, Guoping

    2017-08-01

    It is well known that intelligent control theory has been used in many research fields, novel modeling method (DROMM) is used for flexible rectangular active vibration control, and then the validity of new model is confirmed by comparing finite element model with new model. In this paper, taking advantage of the dynamics of flexible rectangular plate, a two-loop sliding mode (TSM) MIMO approach is introduced for designing multiple-input multiple-output continuous vibration control system, which can overcome uncertainties, disturbances or unstable dynamics. An illustrative example is given in order to show the feasibility of the method. Numerical simulations and experiment confirm the effectiveness of the proposed TSM MIMO controller.

  7. Subterranean termite control examinations on current and former experimental forests and ranges

    Treesearch

    T. G. Shelton; T. L. Wagner; C. J Peterson; J. E. Mulrooney

    2014-01-01

    For more than 70 years, the USDA Forest Service’s Termite Team has engaged in research to extend the life of wood in service by studying chemical (and a few nonchemical) subterranean termite control products. These efficacy data are produced in distinct field trials on experimental forests across the USA, and are used by industry cooperators to register their products...

  8. Air Traffic Control Experimentation and Evaluation with the NASA ATS-6 Satellite : Volume 1. Executive Summary

    DOT National Transportation Integrated Search

    1977-08-01

    The U.S. Department of Transportation (DOT), Federal Aviation Administration (FAA) program for air traffic control (ATC) experimentation and evaluation with the ATS-6 satellite was part of the Integrated ATS-6 L-Band Experiment. All tests were perfor...

  9. Upgrade of U.S. EPA's Experimental Stream Facility Supervisory Control and Data Acquisition System

    EPA Science Inventory

    The Supervisory control and data acquisition (SCADA) system for the U.S. EPA’s Experimental Stream Facility (ESF) was upgraded using Camile hardware and software in 2015. The upgrade added additional hardwired connections, new wireless capabilities, and included a complete rewrit...

  10. Pragmatic Language Outcomes of Children With Attention Deficit Hyperactivity Disorder After Therapist- and Parent-Delivered Play-Based Interventions: Two One-Group Pretest-Posttest Studies With a Longitudinal Component.

    PubMed

    Wilkes-Gillan, Sarah; Munro, Natalie; Cordier, Reinie; Cantrill, Alycia; Pearce, Wendy

    The pragmatic language outcomes of children with attention deficit hyperactivity disorder (ADHD) were explored across two feasibility studies. Five children with ADHD (ages 6-11 yr), their parents, and 5 typically developing peers completed an assessment 18 mo after a therapist-delivered intervention (Study 1). Participants then completed a parent-delivered intervention (Study 2). Blinded ratings of peer-to-peer play interactions documented changes in children's pragmatic language 18 mo after the Study 1 intervention and before, immediately after, and 1 mo after the Study 2 intervention. Nonparametric statistics and Cohen's d were used to measure change. Children's pragmatic language outcomes were maintained 18 mo after the therapist-delivered intervention and significantly improved from before to 1 mo after the parent-delivered intervention. Interventions involving occupational therapist and speech-language pathologist collaboration, play, and parent and peer involvement may facilitate children's pragmatic language skills. Copyright © 2017 by the American Occupational Therapy Association, Inc.

  11. Evaluation of knowledge, attitude, and practice of community pharmacists toward administration of over-the-counter drugs for the treatment of diarrhea in children: A pretest-posttest survey.

    PubMed

    Foroughinia, Farzaneh; Zarei, Pedram

    2016-01-01

    In this study, we aimed to assess knowledge, attitude, and practice of community pharmacists toward administration of over-the-counter (OTC) antidiarrheal drugs in our city pharmacies, Shiraz, Iran. In this descriptive cross-sectional study, 90 pharmacies among 128 pharmacies in our city were randomly chosen. The study was designed into two phases: A standard questionnaire to determine the level of knowledge and attitude of pharmacists and a simulated client method to evaluate practice among them. An educational pamphlet was then given to the pharmacists. One month later, knowledge, attitude, and performance of studied pharmacists were evaluated again using the same method. Our results showed that an average consultation time by female pharmacists was considerably more than male pharmacists (P < 0.001). Before intervention, only 37.8% of pharmacists performed appropriately by prescribing the proper medicine while this increased to 58.44% after intervention. The average score of pharmacists' knowledge was statistically increased (P < 0.001) and the pharmacists' performance was significantly improved (P < 0.001) after the educational intervention. In related to the attitude, pharmacists' tendency toward prescribing oral rehydration salt solutions (ORS) (P < 0.001) and their belief about the great effect of ORS on the treatment of diarrhea increased significantly after the intervention. It is concluded that training programs such as educational pamphlets and continuing educational seminars may play important roles in increasing pharmacists' knowledge and therefore improving their performance in prescribing OTC medicines.

  12. Nurse Middle-Managers: The Relationship of Managerial Motivation to Academic Education, Leadership Training, and Success Potential

    DTIC Science & Technology

    1992-05-12

    compared to an untested one. The quasi-experinmtal design with nonequivalent comparison groups included leadership training between pre and posttests...experimental, pretest-posttest, nonequivalent comparison groups (Wave A & Wave B) design . It allowed investigation of the influence of leadership training on...provided comparison groups . According to Burns and Grove (1987), pretest-posttest designs have inherent threats to validity. Pretest administration

  13. Simulators for Mariner Training and Licensing. Phase 2: Investigation of Simulator-Based Training for Maritime Cadets,

    DTIC Science & Technology

    1981-10-01

    a balance was drawn between experimental considerations (e.g., pretests and posttests ) and training process considerations (e.g., available time and...Station 23 4 Instructor’s Checkoff List 24 5 Port Approach Area 26 6 Training Unit Schedule 28 7 Pretest / Posttest Comparison: CPA - Kings Point Group A (Day...39 a Pretest / Posttest Comparison: Number of Radar Requests - Kings Point Group A (Day) 41 9 Input Characteristic Range Master Notified, Kings Point

  14. The effect of bench model fidelity on fluoroscopy-guided transforaminal epidural injection training: a randomized control study.

    PubMed

    Gonzalez-Cota, Alan; Chiravuri, Srinivas; Stansfield, R Brent; Brummett, Chad M; Hamstra, Stanley J

    2013-01-01

    The purpose of this study was to determine whether high-fidelity simulators provide greater benefit than low-fidelity models in training fluoroscopy-guided transforaminal epidural injection. This educational study was a single-center, prospective, randomized 3-arm pretest-posttest design with a control arm. Eighteen anesthesia and physical medicine and rehabilitation residents were instructed how to perform a fluoroscopy-guided transforaminal epidural injection and assessed by experts on a reusable injectable phantom cadaver. The high- and low-fidelity groups received 30 minutes of supervised hands-on practice according to group assignment, and the control group received 30 minutes of didactic instruction from an expert. We found no differences at posttest between the high- and low-fidelity groups on global ratings of performance (P = 0.17) or checklist scores (P = 0.81). Participants who received either form of hands-on training significantly outperformed the control group on both the global rating of performance (control vs low-fidelity, P = 0.0048; control vs high-fidelity, P = 0.0047) and the checklist (control vs low-fidelity, P = 0.0047; control vs high-fidelity, P = 0.0047). Training an epidural procedure using a low-fidelity model may be equally effective as training on a high-fidelity model. These results are consistent with previous research on a variety of interventional procedures and further demonstrate the potential impact of simple, low-fidelity training models.

  15. Decentralized PID controller for TITO systems using characteristic ratio assignment with an experimental application.

    PubMed

    Hajare, V D; Patre, B M

    2015-11-01

    This paper presents a decentralized PID controller design method for two input two output (TITO) systems with time delay using characteristic ratio assignment (CRA) method. The ability of CRA method to design controller for desired transient response has been explored for TITO systems. The design methodology uses an ideal decoupler to reduce the interaction. Each decoupled subsystem is reduced to first order plus dead time (FOPDT) model to design independent diagonal controllers. Based on specified overshoot and settling time, the controller parameters are computed using CRA method. To verify performance of the proposed controller, two benchmark simulation examples are presented. To demonstrate applicability of the proposed controller, experimentation is performed on real life interacting coupled tank level system. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

  16. Suboptimal LQR-based spacecraft full motion control: Theory and experimentation

    NASA Astrophysics Data System (ADS)

    Guarnaccia, Leone; Bevilacqua, Riccardo; Pastorelli, Stefano P.

    2016-05-01

    This work introduces a real time suboptimal control algorithm for six-degree-of-freedom spacecraft maneuvering based on a State-Dependent-Algebraic-Riccati-Equation (SDARE) approach and real-time linearization of the equations of motion. The control strategy is sub-optimal since the gains of the linear quadratic regulator (LQR) are re-computed at each sample time. The cost function of the proposed controller has been compared with the one obtained via a general purpose optimal control software, showing, on average, an increase in control effort of approximately 15%, compensated by real-time implementability. Lastly, the paper presents experimental tests on a hardware-in-the-loop six-degree-of-freedom spacecraft simulator, designed for testing new guidance, navigation, and control algorithms for nano-satellites in a one-g laboratory environment. The tests show the real-time feasibility of the proposed approach.

  17. The effectiveness of core stabilization exercise in adolescent idiopathic scoliosis: A randomized controlled trial.

    PubMed

    Gür, Gözde; Ayhan, Cigdem; Yakut, Yavuz

    2017-06-01

    Core stabilization training is used to improve postural balance in musculoskeletal problems. The purpose of this study was to investigate the effectiveness of stabilization training in adolescent idiopathic scoliosis. A randomized controlled trial, pretest-posttest design. In total, 25 subjects with adolescent idiopathic scoliosis were randomly divided into two groups: stabilization group ( n = 12) and control group ( n = 13). The stabilization group received core stabilization in addition to traditional rehabilitation, and the control group received traditional rehabilitation for 10 weeks. Assessment included Cobb's angle on radiograph, apical vertebral rotation in Adam's test, trunk asymmetry (Posterior Trunk Symmetry Index), cosmetic trunk deformity (Trunk Appearance Perception Scale), and quality of life (Scoliosis Research Society-22 questionnaire). Inter-group comparisons showed significantly greater improvements in the mean change in lumbar apical vertebral rotation degree and the pain domain of Scoliosis Research Society-22 in the stabilization group than those in the control group ( p < 0.05). No significant differences were observed for other measurements between the groups; however, trends toward greater improvement were observed in the stabilization group. Core stabilization training in addition to traditional exercises was more effective than traditional exercises alone in the correction of vertebral rotation and reduction of pain in adolescent idiopathic scoliosis. Clinical relevance Stabilization exercises are more effective in reducing rotation deformity and pain than traditional exercises in the conservative rehabilitation of adolescent idiopathic scoliosis. These improvements suggest that stabilization training should be added to rehabilitation programs in adolescent idiopathic scoliosis.

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

    NASA Technical Reports Server (NTRS)

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

    1995-01-01

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

  19. Experimental system for computer network via satellite /CS/. III - Network control processor

    NASA Astrophysics Data System (ADS)

    Kakinuma, Y.; Ito, A.; Takahashi, H.; Uchida, K.; Matsumoto, K.; Mitsudome, H.

    1982-03-01

    A network control processor (NCP) has the functions of generating traffics, the control of links and the control of transmitting bursts. The NCP executes protocols, monitors of experiments, gathering and compiling data of measurements, of which programs are loaded on a minicomputer (MELCOM 70/40) with 512KB of memories. The NCP acts as traffic generators, instead of a host computer, in the experiment. For this purpose, 15 fake stations are realized by the software in each user station. This paper describes the configuration of the NCP and the implementation of the protocols for the experimental system.

  20. Experimental demonstration of a phased-array antenna optically controlled with phase and time delays.

    PubMed

    Dolfi, D; Joffre, P; Antoine, J; Huignard, J P; Philippet, D; Granger, P

    1996-09-10

    The experimental demonstration and the far-field pattern characterization of an optically controlled phased-array antenna are described. It operates between 2.5 and 3.5 GHz and is made of 16 radiating elements. The optical control uses a two-dimensional architecture based on free-space propagation and on polarization switching by N spatial light modulators of p × p pixels. It provides 2(N-1) time-delay values and an analog control of the 0 to 2π phase for each of the p × p signals feeding the antenna (N = 5, p = 4).

  1. FRF-based structural damage detection of controlled buildings with podium structures: Experimental investigation

    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.

  2. Influence of the Officer Retention Resource Website on Attitudes and Retention Intentions

    DTIC Science & Technology

    2010-09-01

    Method Design A pretest - posttest control group design was used to assess the impact of the website on officers’ perceptions, attitudes, and retention...covariance (ANCOVA) approach to analyze the data from a pretest - posttest control group design because it generally offers more power than other designs ...between the pretest and posttest is large (r > .70), the gain score approach will have more power than an ANCOVA. Although about one-third of the

  3. Effect of acute fatigue of the hip abductors on control of balance in young and older women.

    PubMed

    Bellew, James W; Panwitz, Beth L; Peterson, Laura; Brock, Mary C; Olson, Katie E; Staples, William H

    2009-07-01

    To examine the effects of acute fatigue of the hip abductors on the control of balance in young and older women. Pretest-posttest. University research laboratory. Healthy young women (n=20; age, 23.0+/-1.5y; height, 166.52+/-4.5 cm; mass, 65.33+/-10.5 kg) and community-dwelling older women (n=20; age, 71.65+/-7.2y; height, 162.31+/-3.8 cm; mass, 71.16+/-11.6 kg) without a fall history. Measurements of control of single-limb balance before and after fatiguing the hip abductors of the dominant leg. Performance on 3 clinical assessments of control of balance: the modified Functional Reach Test in the forward, left, and right directions; the Lower-Extremity Reach Test in forward and lateral directions; and the Single-Limb Stance Time Test (SLSTT). Although the younger subjects showed a significantly greater control of balance than the older women in most tests, control of balance after acute fatigue failed to show a significant decline in either age group. The only exception to this was the SLSTT in the younger women in whom a significant 26% decline was noted (P<.05). Acute fatigue of the hip abductors did not result in a decreased control of balance in healthy young or older women without fall history. Despite considerable changes in movement strategies used to complete the postfatigue tests of balance, quantitative measures of balance did not decrease.

  4. Bioassay selection, experimental design and quality control/assurance for use in effluent assessment and control.

    PubMed

    Johnson, Ian; Hutchings, Matt; Benstead, Rachel; Thain, John; Whitehouse, Paul

    2004-07-01

    In the UK Direct Toxicity Assessment Programme, carried out in 1998-2000, a series of internationally recognised short-term toxicity test methods for algae, invertebrates and fishes, and rapid methods (ECLOX and Microtox) were used extensively. Abbreviated versions of conventional tests (algal growth inhibition tests, Daphnia magna immobilisation test and the oyster embryo-larval development test) were valuable for toxicity screening of effluent discharges and the identification of causes and sources of toxicity. Rapid methods based on chemiluminescence and bioluminescence were not generally useful in this programme, but may have a role where the rapid test has been shown to be an acceptable surrogate for a standardised test method. A range of quality assurance and control measures were identified. Requirements for quality control/assurance are most stringent when deriving data for characterising the toxic hazards of effluents and monitoring compliance against a toxicity reduction target. Lower quality control/assurance requirements can be applied to discharge screening and the identification of causes and sources of toxicity.

  5. Progress Towards Fuselage Drag Reduction via Active Flow Control: A Combined CFD and Experimental Effort

    NASA Technical Reports Server (NTRS)

    Schaeffler, Norman W.; Allan, Brian G.; Lienard, Caroline; LePape, Arnaud

    2010-01-01

    A combined computational and experimental effort has been undertaken to study fuselage drag reduction on a generic, non-proprietary rotorcraft fuselage by the application of active ow control. Fuselage drag reduction is an area of research interest to both the United States and France and this area is being worked collaboratively as a task under the United States/France Memorandum of Agreement on Helicopter Aeromechanics. In the first half of this task, emphasis is placed on the US generic fuselage, the ROBIN-mod7, with the experimental work being conducted on the US side and complementary US and French CFD analysis of the baseline and controlled cases. Fuselage simulations were made using Reynolds-averaged Navier-Stokes ow solvers and with multiple turbulence models. Comparisons were made to experimental data for numerical simulations of the isolated fuselage and for the fuselage as installed in the tunnel, which includes modeling of the tunnel contraction, walls, and support fairing. The numerical simulations show that comparisons to the experimental data are in good agreement when the tunnel and model support are included. The isolated fuselage simulations compare well to each other, however, there is a positive shift in the centerline pressure when compared to the experiment. The computed flow separation locations on the rear ramp region had only slight differences with and without the tunnel walls and model support. For the simulations, the flow control slots were placed at several locations around the flow separation lines as a series of eight slots that formed a nearly continuous U-shape. Results from the numerical simulations resulted in an estimated 35% fuselage drag reduction from a steady blowing flow control configuration and a 26% drag reduction for unsteady zero-net-mass flow control configuration. Simulations with steady blowing show a delayed flow separation at the rear ramp of the fuselage that increases the surface pressure acting on the ramp

  6. PLACE: an open-source python package for laboratory automation, control, and experimentation.

    PubMed

    Johnson, Jami L; Tom Wörden, Henrik; van Wijk, Kasper

    2015-02-01

    In modern laboratories, software can drive the full experimental process from data acquisition to storage, processing, and analysis. The automation of laboratory data acquisition is an important consideration for every laboratory. When implementing a laboratory automation scheme, important parameters include its reliability, time to implement, adaptability, and compatibility with software used at other stages of experimentation. In this article, we present an open-source, flexible, and extensible Python package for Laboratory Automation, Control, and Experimentation (PLACE). The package uses modular organization and clear design principles; therefore, it can be easily customized or expanded to meet the needs of diverse laboratories. We discuss the organization of PLACE, data-handling considerations, and then present an example using PLACE for laser-ultrasound experiments. Finally, we demonstrate the seamless transition to post-processing and analysis with Python through the development of an analysis module for data produced by PLACE automation. © 2014 Society for Laboratory Automation and Screening.

  7. Experimental implementation of acoustic impedance control by a 2D network of distributed smart cells

    NASA Astrophysics Data System (ADS)

    David, P.; Collet, M.; Cote, J.-M.

    2010-03-01

    New miniaturization and integration capabilities available from emerging microelectromechanical system (MEMS) technology will allow silicon-based artificial skins involving thousands of elementary actuators to be developed in the near future. Smart structures combining large arrays of elementary motion pixels are thus being studied so that fundamental properties could be dynamically adjusted. This paper investigates the acoustical capabilities of a network of distributed transducers connected with a suitable controlling strategy. The research aims at designing an integrated active interface for sound attenuation by using suitable changes of acoustical impedance. The control strategy is based on partial differential equations (PDE) and the multiscaled physics of electromechanical elements. Specific techniques based on PDE control theory have provided a simple boundary control equation able to annihilate the reflections of acoustic waves. To experimentally implement the method, the control strategy is discretized as a first order time-space operator. The obtained quasi-collocated architecture, composed of a large number of sensors and actuators, provides high robustness and stability. The experimental results demonstrate how a well controlled active skin can substantially modify sound reflectivity of the acoustical interface and reduce the propagation of acoustic waves.

  8. [Effectiveness of a school weight control program].

    PubMed

    Huang, Hsiu-Mei; Wu, Mei-Chan; Chen, Kuei-Hsiang

    2010-06-01

    School-based health promotion programs have been shown to reduce the incidence of obesity in students and improve student physical fitness. However, few longitudinal evaluations of the effectiveness of such programs have been conducted. The purpose of this study was to assess the effectiveness of an in-school weight control program. Data was collected prior to and after the school's summer vacation period. The study utilized a one-group pretest-posttest design. Overweight and obese children from the fifth grade in an elementary school in Taipei City were selected as purposive samples. The study, which was conducted between March and June 2007, introduced general obesity concepts, taught basic nutrition education, and organized a physical activity program that comprised two 45-min exercise sessions during the week and one 30-min session activity each weekend. The obesity index assessed the body mass index (BMI) and waist-to-height ratio (WHtR), with physical fitness tests conducted before and after student summer vacations to assess achieved weight control results. The nonparametric test and repeat measure were used to assess weight control program effectiveness. After the weight control program, significant declines in BMI and WHtR (p < .001), significant improvements in 800-m run/walk (p < .01) and 1-minute sit-up tests (p < .05) were recorded. However, no significant comparative improvement was achieved on either obesity index or physical fitness test. Weight control programs represent an effective approach to reduce BMI and WHtR and improve physical fitness. An appropriate diet and exercise are important for school-aged children to maintain effective weight control and physical fitness health.

  9. Indicated cognitive behavioral group depression prevention compared to bibliotherapy and brochure control: acute effects of an effectiveness trial with adolescents.

    PubMed

    Rohde, Paul; Stice, Eric; Shaw, Heather; Brière, Frédéric N

    2014-02-01

    We tested whether a brief cognitive behavioral (CB) group and bibliotherapy prevention reduce major depressive disorder (MDD) onset, depressive symptoms, and secondary outcomes relative to brochure controls in adolescents with self-reported depressive symptoms when school personnel recruit participants and deliver the intervention. Three hundred seventy-eight adolescents (M age = 15.5 years, SD = 1.2; 68% female, 72% White) with elevated self-assessed depressive symptoms were randomized to a 6-session CB group, minimal contact CB bibliotherapy, or educational brochure control. Participants were assessed at pretest, posttest, and 6-month follow-up. CB group participants showed a significantly lower risk for major depressive disorder onset (0.8%), compared to both CB bibliotherapy (6.3%) and brochure control (6.5%; hazard ratio = 8.1 and 8.3, respectively). Planned contrasts indicated that CB group resulted in lower depressive symptom severity than brochure control at posttest (p = .03, d = 0.29) but not 6-month follow-up; differences between CB group and bibliotherapy were nonsignificant at posttest and 6-month follow-up. Condition effects were nonsignificant for social adjustment and substance use. The finding that a brief CB group intervention delivered by real-world providers significantly reduced MDD onset relative to both brochure control and bibliotherapy is very encouraging, although effects on continuous outcome measures were small or nonsignificant and approximately half the magnitude of those found in efficacy research, potentially because the present sample reported lower initial depression.

  10. Optimal design and experimental analyses of a new micro-vibration control payload-platform

    NASA Astrophysics Data System (ADS)

    Sun, Xiaoqing; Yang, Bintang; Zhao, Long; Sun, Xiaofen

    2016-07-01

    This paper presents a new payload-platform, for precision devices, which possesses the capability of isolating the complex space micro-vibration in low frequency range below 5 Hz. The novel payload-platform equipped with smart material actuators is investigated and designed through optimization strategy based on the minimum energy loss rate, for the aim of achieving high drive efficiency and reducing the effect of the magnetic circuit nonlinearity. Then, the dynamic model of the driving element is established by using the Lagrange method and the performance of the designed payload-platform is further discussed through the combination of the controlled auto regressive moving average (CARMA) model with modified generalized prediction control (MGPC) algorithm. Finally, an experimental prototype is developed and tested. The experimental results demonstrate that the payload-platform has an impressive potential of micro-vibration isolation.

  11. Numerical analysis and experimental studies on solenoid common rail diesel injector with worn control valve

    NASA Astrophysics Data System (ADS)

    Krivtsov, S. N.; Yakimov, I. V.; Ozornin, S. P.

    2018-03-01

    A mathematical model of a solenoid common rail fuel injector was developed. Its difference from existing models is control valve wear simulation. A common rail injector of 0445110376 Series (Cummins ISf 2.8 Diesel engine) produced by Bosch Company was used as a research object. Injector parameters (fuel delivery and back leakage) were determined by calculation and experimental methods. GT-Suite model average R2 is 0.93 which means that it predicts the injection rate shape very accurately (nominal and marginal technical conditions of an injector). Numerical analysis and experimental studies showed that control valve wear increases back leakage and fuel delivery (especially at 160 MPa). The regression models for determining fuel delivery and back leakage effects on fuel pressure and energizing time were developed (for nominal and marginal technical conditions).

  12. Youth Attitude Tracking Study II, Fall 1983.

    DTIC Science & Technology

    1983-01-01

    one - group pretest - posttest design." In this, though a . "before" group of the same individuals is introduced...there is no control group that is not exposed to the event. S Both the one -shot case study and the one - group pretest - posttest design are subject to a...segmentation analysis -A identified five Recruiting Priority Groups on the basis of educational status and average grades earned in high school.

  13. Developing Adaptive Training in the Classroom

    DTIC Science & Technology

    2009-09-01

    change to a training course: a pretest / posttest design and the use of control groups.39 The pretest / posttest comparison would entail administering the...U.S. Army Research Institute for the Behavioral and Social Sciences Research Product 2009-10 Developing Adaptive Training in...the Classroom Rose A. Mueller-Hanson Personnel Decisions Research Institutes, Inc. Michelle M. Wisecarver U.S. Army Research Institute

  14. Generation of Quality Pulses for Control of Qubit/Quantum Memory Spin States: Experimental and Simulation

    DTIC Science & Technology

    2016-09-01

    TECHNICAL REPORT 3046 September 2016 GENERATION OF QUALITY PULSES FOR CONTROL OF QUBIT/QUANTUM MEMORY SPIN STATES: EXPERIMENTAL AND SIMULATION...nuclear spin states of qubits/quantum memory applicable to semiconductor, superconductor, ionic, and superconductor-ionic hybrid technologies. As the...pulse quality and need for development of single pulses with very high quality will impact directly the coherence time of the qubit/ memory , we present

  15. Shoreline Erosion and Proposed Control at Experimental Facility 15-Spesutie Island

    DTIC Science & Technology

    2017-09-01

    Island, it is made up of various facilities and ranges designed for weapons testing as well as automotive testing . These ranges belong to the...ARL-SR-0383 ● SEP 2017 US Army Research Laboratory Shoreline Erosion and Proposed Control at Experimental Facility 15–Spesutie...in this report are not to be construed as an official Department of the Army position unless so designated by other authorized documents. Citation

  16. SuperState: a computer program for the control of operant behavioral experimentation.

    PubMed

    Zhang, Fuqiang

    2006-09-15

    Operant behavioral researches require precise control of experimental devices for delivering stimuli and monitoring behavioral responses. The author developed a software solution named SuperState for controlling hardware devices and running reinforcement schedules. The Microsoft Windows compatible software was written by use of an object-oriented programming language Borland Delphi 5.0, which has simplified the programming of the application. SuperState is a stand-alone easy-to-use green software, without the need for the experimenter to master any scripting languages. It features: (1) control of multiple operant cages running independent reinforcement schedules; (2) enough cage devices (16 digital inputs and 16 digital outputs for each cage) suitable for the need of most operant behavioral equipments; (3) control of most standard ISA-type digital interface cards including Med-Associates Super-port cards and a PCI-type card AC6412, and highly expandable to support other PCI-type interface cards; (4) high-resolution device control (1ms); (5) a built-in real-time cumulative recorder; (6) extensive data analyzing including event recorder, cumulative recorder, block analyzing; the summarized results can be transferred easily to Microsoft Excel spreadsheets through the Clipboard.

  17. Frequency-independent radiation modes of interior sound radiation: Experimental study and global active control

    NASA Astrophysics Data System (ADS)

    Hesse, C.; Papantoni, V.; Algermissen, S.; Monner, H. P.

    2017-08-01

    Active control of structural sound radiation is a promising technique to overcome the poor passive acoustic isolation performance of lightweight structures in the low-frequency region. Active structural acoustic control commonly aims at the suppression of the far-field radiated sound power. This paper is concerned with the active control of sound radiation into acoustic enclosures. Experimental results of a coupled rectangular plate-fluid system under stochastic excitation are presented. The amplitudes of the frequency-independent interior radiation modes are determined in real-time using a set of structural vibration sensors, for the purpose of estimating their contribution to the acoustic potential energy in the enclosure. This approach is validated by acoustic measurements inside the cavity. Utilizing a feedback control approach, a broadband reduction of the global acoustic response inside the enclosure is achieved.

  18. Servo-hydraulic actuator in controllable canonical form: Identification and experimental validation

    NASA Astrophysics Data System (ADS)

    Maghareh, Amin; Silva, Christian E.; Dyke, Shirley J.

    2018-02-01

    Hydraulic actuators have been widely used to experimentally examine structural behavior at multiple scales. Real-time hybrid simulation (RTHS) is one innovative testing method that largely relies on such servo-hydraulic actuators. In RTHS, interface conditions must be enforced in real time, and controllers are often used to achieve tracking of the desired displacements. Thus, neglecting the dynamics of hydraulic transfer system may result either in system instability or sub-optimal performance. Herein, we propose a nonlinear dynamical model for a servo-hydraulic actuator (a.k.a. hydraulic transfer system) coupled with a nonlinear physical specimen. The nonlinear dynamical model is transformed into controllable canonical form for further tracking control design purposes. Through a number of experiments, the controllable canonical model is validated.

  19. Experimental study of a self-powered and sensing MR-damper-based vibration control system

    NASA Astrophysics Data System (ADS)

    Sapiński, Bogdan

    2011-10-01

    The paper deals with a semi-active vibration control system based on a magnetorheological (MR) damper. The study outlines the model and the structure of the system, and describes its experimental investigation. The conceptual design of this system involves harvesting energy from structural vibrations using an energy extractor based on an electromagnetic transduction mechanism (Faraday's law). The system consists of an electromagnetic induction device (EMI) prototype and an MR damper of RD-1005 series manufactured by Lord Corporation. The energy extracted is applied to control the damping characteristics of the MR damper. The model of the system was used to prove that the proposed vibration control system is feasible. The system was realized in the semi-active control strategy with energy recovery and examined through experiments in the cases where the control coil of the MR damper was voltage-supplied directly from the EMI or voltage-supplied via the rectifier, or supplied with a current control system with two feedback loops. The external loop used the sky-hook algorithm whilst the internal loop used the algorithm switching the photorelay, at the output from the rectifier. Experimental results of the proposed vibration control system were compared with those obtained for the passive system (MR damper is off-state) and for the system with an external power source (conventional system) when the control coil of the MR damper was supplied by a DC power supply and analogue voltage amplifier or a DC power supply and a photorelay. It was demonstrated that the system is able to power-supply the MR damper and can adjust itself to structural vibrations. It was also found that, since the signal of induced voltage from the EMI agrees well with that of the relative velocity signal across the damper, the device can act as a 'velocity-sign' sensor.

  20. Is EEG-biofeedback an effective treatment in autism spectrum disorders? A randomized controlled trial.

    PubMed

    Kouijzer, Mirjam E J; van Schie, Hein T; Gerrits, Berrie J L; Buitelaar, Jan K; de Moor, Jan M H

    2013-03-01

    EEG-biofeedback has been reported to reduce symptoms of autism spectrum disorders (ASD) in several studies. However, these studies did not control for nonspecific effects of EEG-biofeedback and did not distinguish between participants who succeeded in influencing their own EEG activity and participants who did not. To overcome these methodological shortcomings, this study evaluated the effects of EEG-biofeedback in ASD in a randomized pretest-posttest control group design with blinded active comparator and six months follow-up. Thirty-eight participants were randomly allocated to the EEG-biofeedback, skin conductance (SC)-biofeedback or waiting list group. EEG- and SC-biofeedback sessions were similar and participants were blinded to the type of feedback they received. Assessments pre-treatment, post-treatment, and after 6 months included parent ratings of symptoms of ASD, executive function tasks, and 19-channel EEG recordings. Fifty-four percent of the participants significantly reduced delta and/or theta power during EEG-biofeedback sessions and were identified as EEG-regulators. In these EEG-regulators, no statistically significant reductions of symptoms of ASD were observed, but they showed significant improvement in cognitive flexibility as compared to participants who managed to regulate SC. EEG-biofeedback seems to be an applicable tool to regulate EEG activity and has specific effects on cognitive flexibility, but it did not result in significant reductions in symptoms of ASD. An important finding was that no nonspecific effects of EEG-biofeedback were demonstrated.

  1. Aerobic circuit exercise training: effect on adolescents with well-controlled insulin-dependent diabetes mellitus.

    PubMed

    Mosher, P E; Nash, M S; Perry, A C; LaPerriere, A R; Goldberg, R B

    1998-06-01

    To test the safety and effects of exercise conditioning on cardiorespiratory fitness, body composition, muscle strength, glucose regulation, and lipid/cholesterol levels. Ten male adolescents with insulin-dependent diabetes mellitus (IDDM) and 10 adolescent nondiabetic (ND) subjects. Pretest, posttest intervention trial with control group. University-based human performance laboratory. Mixed endurance and calisthenic/strength activities performed at a rapid pace three times weekly for 12 weeks. Only one subject with IDDM experienced hypoglycemia after a single exercise session. Both subject groups improved their cardiorespiratory endurance (p < .05). Lean body mass of IDDM subjects increased by 3.5% (p < .05). Subjects with and without IDDM lowered their percent body fat (p < .05 and .001, respectively). Strength improvement of IDDM subjects ranged from 13.7% (p < .001) to 44.4% (p < .01), depending upon the maneuver. Fasting blood plasma glucose for all subjects was unchanged by training, but glycosylated hemoglobin A1c of IDDM subjects was reduced by .96 percentage point (p < .05). Reductions of HbA1c benefitted subjects exhibiting poor preconditioning glycemic control. Low-density lipoprotein cholesterol was decreased in subjects with IDDM (p < .05), but not total cholesterol or triglycerides. Adolescents with IDDM undergoing aerobic circuit training improve their cardiorespiratory endurance, muscle strength, lipid profile, and glucose regulation. Aerobic circuit training is safe for properly trained and monitored adolescent diabetics.

  2. The Effects of Music Intervention on Background Pain and Anxiety in Burn Patients: Randomized Controlled Clinical Trial.

    PubMed

    Najafi Ghezeljeh, Tahereh; Mohades Ardebili, Fatimah; Rafii, Forough; Haghani, Hamid

    2016-01-01

    This study aimed to investigate the effect of music on the background pain, anxiety, and relaxation levels in burn patients. In this pretest-posttest randomized controlled clinical trial, 100 hospitalized burn patients were selected through convenience sampling. Subjects randomly assigned to music and control groups. Data related to demographic and clinical characteristics, analgesics, and physiologic measures were collected by researcher-made tools. Visual analog scale was used to determine pain, anxiety, and relaxation levels before and after the intervention in 3 consecutive days. Patients' preferred music was offered once a day for 3 days. The control group only received routine care. Data were analyzed using SPSS-PC (V. 20.0). According to paired t-test, there were significant differences between mean scores of pain (P < .001), anxiety (P < .001), and relaxation (P < .001) levels before and after intervention in music group. Independent t-test indicated a significant difference between the mean scores of changes in pain, anxiety, and relaxation levels before and after intervention in music and control groups (P < .001). No differences were detected in the mean scores of physiologic measures between groups before and after music intervention. Music is an inexpensive, appropriate, and safe intervention for applying to burn patients with background pain and anxiety at rest. To produce more effective comfort for patients, it is necessary to compare different types and time lengths of music intervention to find the best approach.

  3. The active learning hypothesis of the job-demand-control model: an experimental examination.

    PubMed

    Häusser, Jan Alexander; Schulz-Hardt, Stefan; Mojzisch, Andreas

    2014-01-01

    The active learning hypothesis of the job-demand-control model [Karasek, R. A. 1979. "Job Demands, Job Decision Latitude, and Mental Strain: Implications for Job Redesign." Administration Science Quarterly 24: 285-307] proposes positive effects of high job demands and high job control on performance. We conducted a 2 (demands: high vs. low) × 2 (control: high vs. low) experimental office workplace simulation to examine this hypothesis. Since performance during a work simulation is confounded by the boundaries of the demands and control manipulations (e.g. time limits), we used a post-test, in which participants continued working at their task, but without any manipulation of demands and control. This post-test allowed for examining active learning (transfer) effects in an unconfounded fashion. Our results revealed that high demands had a positive effect on quantitative performance, without affecting task accuracy. In contrast, high control resulted in a speed-accuracy tradeoff, that is participants in the high control conditions worked slower but with greater accuracy than participants in the low control conditions.

  4. A Field Test of a Web-Based Workplace Health Promotion Program to Improve Dietary Practices, Reduce Stress, and Increase Physical Activity: Randomized Controlled Trial

    PubMed Central

    Billings, Douglas W; Hersch, Rebekah K; Back, Anita S; Hendrickson, April

    2007-01-01

    Background Most work sites engage in some form of health promotion programming designed to improve worker health and reduce health care costs. Although these programs have typically been delivered through combinations of seminars and print materials, workplace health promotion programs are increasingly being delivered through the Internet. Objective The purpose of this research was to evaluate the effectiveness of a Web-based multimedia health promotion program for the workplace, designed to improve dietary practices, reduce stress, and increase physical activity. Methods Using a randomized controlled trial design with pretest-posttest comparisons within each group, 419 employees of a human resources company were randomly assigned to the Web-based condition or to a condition that provided print materials on the same topics. All subjects were assessed at pretest and posttest through an online questionnaire containing multiple measures of health behavior and attitudes. The test period was 3 months. Questionnaire data were analyzed mainly by analysis of covariance and t tests. Results Retention rates were good for both groups—85% for the Web-based group and 87% for the print group. Subjects using the Web-based program performed significantly better than the print group on Attitudes Toward a Healthful Diet (F1,415 = 7.104, P = .008) and Dietary Stage of Change (F1,408 = 6.487, P = .01), but there were no significant group differences on the five other dietary measures. Both groups also showed improvement from pretest to posttest on most dietary measures, as indicated by significant t tests. Within the Web-based group, dosage analyses showed significant effects of the number of times the subject accessed the program on measures of Dietary Self-Efficacy (F2,203 = 5.270, P = .003), Attitudes Toward a Healthful Diet (F2,204 = 2.585, P = .045), and Dietary Stage of Change (F2,200 = 4.627, P = .005). No significant differences were found between the two groups on measures

  5. A field test of a web-based workplace health promotion program to improve dietary practices, reduce stress, and increase physical activity: randomized controlled trial.

    PubMed

    Cook, Royer F; Billings, Douglas W; Hersch, Rebekah K; Back, Anita S; Hendrickson, April

    2007-06-19

    Most work sites engage in some form of health promotion programming designed to improve worker health and reduce health care costs. Although these programs have typically been delivered through combinations of seminars and print materials, workplace health promotion programs are increasingly being delivered through the Internet. The purpose of this research was to evaluate the effectiveness of a Web-based multimedia health promotion program for the workplace, designed to improve dietary practices, reduce stress, and increase physical activity. Using a randomized controlled trial design with pretest-posttest comparisons within each group, 419 employees of a human resources company were randomly assigned to the Web-based condition or to a condition that provided print materials on the same topics. All subjects were assessed at pretest and posttest through an online questionnaire containing multiple measures of health behavior and attitudes. The test period was 3 months. Questionnaire data were analyzed mainly by analysis of covariance and t tests. Retention rates were good for both groups-85% for the Web-based group and 87% for the print group. Subjects using the Web-based program performed significantly better than the print group on Attitudes Toward a Healthful Diet (F(1,415) = 7.104, P = .008) and Dietary Stage of Change (F(1,408) = 6.487, P = .01), but there were no significant group differences on the five other dietary measures. Both groups also showed improvement from pretest to posttest on most dietary measures, as indicated by significant t tests. Within the Web-based group, dosage analyses showed significant effects of the number of times the subject accessed the program on measures of Dietary Self-Efficacy (F(2,203) = 5.270, P = .003), Attitudes Toward a Healthful Diet (F(2,204) = 2.585, P = .045), and Dietary Stage of Change (F(2,200) = 4.627, P = .005). No significant differences were found between the two groups on measures of stress or physical

  6. The effect of interprofessional team-based learning among nursing students: A quasi-experimental study.

    PubMed

    Wong, Arkers Kwan Ching; Wong, Frances Kam Yuet; Chan, Lap Ki; Chan, Namkiu; Ganotice, Fraide A; Ho, Jacqueline

    2017-06-01

    Although interprofessional education has received attention in recent years as a means of providing opportunities for health-care professionals to learn with, from and about other disciplines and enhance the quality of patient care, evidence of its effectiveness is limited. Interprofessional team-based learning was introduced to make it possible for students in different healthcare disciplines to interact with each other, and to prepare them to function effectively within a team in their future career. To examine the effects of interprofessional team-based learning for undergraduate nursing students in terms of knowledge level, readiness for interprofessional learning, attitude towards various aspects of team learning, and perceived collective efficacy. The study employed a one-group pretest-posttest quasi-experimental design. An interprofessional education program was given to students from two universities in Hong Kong who were in different healthcare disciplines including medicine, nursing, pharmacy, biomedical science, and Chinese medicine programs. The program was based on four phases of student learning- individual readiness assessment test, ice breaking session, team readiness assessment test, and application exercise. Nursing students involved in the program were invited to complete anonymous questionnaires to evaluate their interprofessional team experience. A total of 40 nursing students (9 male, 31 female) participated in the study. A statistically significant improvement was identified in their knowledge level (p<0.001), attitude towards readiness for interprofessional learning, team learning, and perceived collective efficacy (p<0.001). This study suggests that interprofessional team-based learning can enhance cross-disciplinary learning and outcomes resulting from team efforts. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Quasi-experimental evaluation of a telephone-based peer support intervention for maternal depression.

    PubMed

    Letourneau, Nicole; Secco, Loretta; Colpitts, Jennifer; Aldous, Sarah; Stewart, Miriam; Dennis, Cindy-Lee

    2015-07-01

    To evaluate the effect of telephone-based peer support on maternal depression and social support Postpartum depression is a global health concern and lack of treatment options mean many mothers are depressed beyond the first year after birth. Strong evidence has shown telephone-based peer support, provided by a mother recovered from depression, effectively improves depression outcomes. This model has not been tested with mothers with depression any time up to two years postpartum. Quasi-experimental, one group pre-test, posttest. The study population was mothers in New Brunswick, Canada with depression up to 24 months after delivery. The sample (N = 64) was recruited between May 2011-October 2013. Peer volunteers recovered from postpartum depression were trained and delivered an average of 8·84 (Range 1-13) support telephone calls. Depression and social support outcomes were assessed at intervention mid-point (average 7·43 weeks, n = 37) and end (average 13·9 weeks, n = 34). Mean depression significantly declined from baseline, 15·4 (N = 49), to mid-point, 8·30 and end of the study, 6·26. At mid-point 8·1% (n = 3/37) of mothers were depressed and at endpoint 11·8% (4/34) were depressed suggesting some relapse. Perceptions of social support significantly improved and higher support was significantly related with lower depression symptoms. Findings offer promise that telephone-based peer support is effective for both early postpartum depression and maternal depression up to two years after delivery. © 2015 John Wiley & Sons Ltd.

  8. Efficacy of empathy training in nursing students: A quasi-experimental study.

    PubMed

    Bas-Sarmiento, Pilar; Fernández-Gutiérrez, Martina; Baena-Baños, María; Romero-Sánchez, Jose Manuel

    2017-12-01

    Empathy is a competency to be learned by nurses and a therapeutic tool in the helping relationship that has repercussions on the health of both patients and professionals. To determine the efficacy of an experiential training for improving the empathy of nursing students in terms of capacity building, empathic performance and increased learning perception and retention of the material. A quasi-experimental study of a single group with pretest-posttest measurements of the educational intervention and follow-up at one month after the training. Faculty of Nursing, University of Cádiz, Spain. Forty-eight second-year undergraduate university nursing students. The educational intervention was conducted during a single semester, with 20h of training. The methodology of role-playing, behavior assay, and a flipped classroom was followed. Measurements of student performance were collected before and after the intervention. The Reynolds Empathy Scale was used to evaluate the student's perception of his/her performance; The Consultation and Relational Empathy Measure was used to evaluate the patient's perception of the student's behavior during the simulation; and three independent external observers assessed the student's behavior, guided by The Carkhuff Scale. Descriptive analysis and non-parametric contrast tests were performed to compare the scores before and after the training (Mann-Whitney U and Wilcoxon rank-sum). Spearman's correlation coefficient was used for the correlation between the measurements. The mean scores improved for all of the variables, with the differences being statistically significant. The students assessed their learning positively. The training was shown to be effective for improving the empathy of the university students in the study. The results are promising in terms of the students retaining the competencies adquired. Therefore, this type of experiential training is recommended for empathy training of future health professionals. Copyright

  9. Effects of constructivist teaching methods on bioethics education for nursing students: a quasi-experimental study.

    PubMed

    Choe, Kwisoon; Park, Sunghee; Yoo, So Yeon

    2014-05-01

    In order to help nurses advocate for the patient's human rights and ensure respect for life in clinical situations, it is of utmost importance to improve nursing students' capacity to make ethical decisions. This study compares the effects of two constructivist teaching strategies (action learning and cross-examination debate) on nursing students' recognition of bioethical issues, experience of bioethical issues, and attainment of ethical competence. This study used a quasi-experimental (two-group pretest-posttest) design. A nursing college in South Korea. A total of 93 Korean nursing students participated in the study (46 in the action learning group and 47 in the cross-examination debate group). Participants took a bioethics class employing one or the other of the strategies mentioned, 2h a week for 15 weeks. All participants responded twice to a set of questionnaires, at the beginning of the first session and at the end of the last session. After their bioethics education, the students' recognition of bioethical issues improved for both classes; however, the knowledge of students who had participated in action learning improved more than that of the students in the debate-based class. Students in both groups reported more experience of bioethics and exposure to better-quality instruction in bioethics after their classes than previously. Students in both groups also reported improved ethical competency after this education. Positive effects of action learning and cross-examination debate implemented as teaching strategies on nursing students' understanding of bioethical issues and their ethical competency were identified; these findings will be important in the essential task of teaching bioethics to nursing students in order to foster more ethical decision-making and other ethical behavior. © 2013.

  10. Cognitive-behavioral group depression prevention compared to bibliotherapy and brochure control: nonsignificant effects in pilot effectiveness trial with college students.

    PubMed

    Rohde, Paul; Stice, Eric; Shaw, Heather; Gau, Jeff M

    2014-04-01

    Conduct a pilot trial testing whether a brief cognitive-behavioral (CB) group reduced depressive symptoms and secondary outcomes relative to bibliotherapy and brochure controls in college students with elevated depressive symptoms. 82 college students (M age=19.0, SD=0.9; 70% female, 80% White) with elevated self-assessed depressive symptoms were randomized to a 6-session CB group, bibliotherapy, or educational brochure control condition, completing assessments at pretest, posttest, and at 6- and 12-month follow-up. Planned contrasts found no significant effects for CB group on depressive symptoms compared to either bibliotherapy or brochure controls at posttest (d=-.08 and .06, respectively) or over follow-up (d=-.04 and -.10, respectively). There were no intervention effects for social adjustment and substance use, though CB group participants had improved knowledge of CB concepts at posttest, versus brochure controls. Condition differences in major depression onset were nonsignificant but suggested support for CB interventions (CB group=7.4%, bibliotherapy=4.5%, brochure control=15.2%). Unexpectedly modest support was found for a brief CB group depression prevention intervention, compared to bibliotherapy or brochure control, when provided to self-selected college students, suggesting that alternative screening or interventions approaches are needed for this population. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Experimental setup for evaluating an adaptive user interface for teleoperation control

    NASA Astrophysics Data System (ADS)

    Wijayasinghe, Indika B.; Peetha, Srikanth; Abubakar, Shamsudeen; Saadatzi, Mohammad Nasser; Cremer, Sven; Popa, Dan O.

    2017-05-01

    A vital part of human interactions with a machine is the control interface, which single-handedly could define the user satisfaction and the efficiency of performing a task. This paper elaborates the implementation of an experimental setup to study an adaptive algorithm that can help the user better tele-operate the robot. The formulation of the adaptive interface and associate learning algorithms are general enough to apply when the mapping between the user controls and the robot actuators is complex and/or ambiguous. The method uses a genetic algorithm to find the optimal parameters that produce the input-output mapping for teleoperation control. In this paper, we describe the experimental setup and associated results that was used to validate the adaptive interface to a differential drive robot from two different input devices; a joystick, and a Myo gesture control armband. Results show that after the learning phase, the interface converges to an intuitive mapping that can help even inexperienced users drive the system to a goal location.

  12. Accelerated optimization and automated discovery with covariance matrix adaptation for experimental quantum control

    NASA Astrophysics Data System (ADS)

    Roslund, Jonathan; Shir, Ofer M.; Bäck, Thomas; Rabitz, Herschel

    2009-10-01

    Optimization of quantum systems by closed-loop adaptive pulse shaping offers a rich domain for the development and application of specialized evolutionary algorithms. Derandomized evolution strategies (DESs) are presented here as a robust class of optimizers for experimental quantum control. The combination of stochastic and quasi-local search embodied by these algorithms is especially amenable to the inherent topology of quantum control landscapes. Implementation of DES in the laboratory results in efficiency gains of up to ˜9 times that of the standard genetic algorithm, and thus is a promising tool for optimization of unstable or fragile systems. The statistical learning upon which these algorithms are predicated also provide the means for obtaining a control problem’s Hessian matrix with no additional experimental overhead. The forced optimal covariance adaptive learning (FOCAL) method is introduced to enable retrieval of the Hessian matrix, which can reveal information about the landscape’s local structure and dynamic mechanism. Exploitation of such algorithms in quantum control experiments should enhance their efficiency and provide additional fundamental insights.

  13. Vancomycin containing PLLA/β-TCP controls experimental osteomyelitis in vivo.

    PubMed

    Kankilic, Berna; Bilgic, Elif; Korkusuz, Petek; Korkusuz, Feza

    2014-11-19

    Implant-related osteomyelitis (IRO) is recently controlled with local antibiotic delivery systems to overcome conventional therapy disadvantages. In vivo evaluation of such systems is however too little. We asked whether vancomycin (V)-containing poly-l-lactic acid/β-tricalcium phosphate (PLLA/β-TCP) composites control experimental IRO and promote bone healing in vivo. Fifty-six rats were distributed to five groups in this longitudinal controlled study. Experimental IRO was established at tibiae by injecting methicillin-resistant Staphylococcus aureus (MRSA) suspensions with titanium particles in 32 rats. Vancomycin-free PLLA/β-TCP composites were implanted into the normal and infected tibiae, whereas V-PLLA/β-TCP composites and coated (C)-V-PLLA/β-TCP composites were implanted into IRO sites. Sham-operated tibiae established the control group. Radiological and histological scores were quantified with microbiological findings on weeks 1 and 6. IRO is resolved in the CV- and the V-PLLA/β-TCP groups but not in the PLLA/β-TCP group. MRSA was not isolated in the CV- and the V-PLLA/β-TCP groups at all times whereas the bacteria were present in the PLLA/β-TCP group. Radiological signs secondary to infection are improved from 10.9 ± 0.9 to 3.0 ± 0.3 in the V-PLLA/β-TCP group but remained constant in the PLLA/β-TCP group. Histology scores are improved from 24.7 ± 6.5 to 17.6 ± 4.8 and from 27.6 ± 7.9 to 32.4 ± 8.9 in the CV-PLLA/β-TCP and the V-PLLA/β-TCP groups, respectively. New bone was formed in all the PLLA/β-TCP group at weeks 1 and 6. CV- and V-PLLA/β-TCP composites controlled experimental IRO and promoted bone healing. CV- and V-PLLA/β-TCP composites have the potential of controlling experimental IRO and promoting bone healing.

  14. The impact of maternal control on children's anxious cognitions, behaviours and affect: an experimental study.

    PubMed

    Thirlwall, Kerstin; Creswell, Cathy

    2010-10-01

    Controlling parenting is associated with child anxiety however the direction of effects remains unclear. The present study implemented a Latin-square experimental design to assess the impact of parental control on children's anxious affect, cognitions and behaviour. A non-clinical sample of 24 mothers of children aged 4-5 years were trained to engage in (a) controlling and (b) autonomy-granting behaviours in interaction with their child during the preparation of a speech. When mothers engaged in controlling parenting behaviours, children made more negative predictions about their performance prior to delivering their speech and reported feeling less happy about the task, and this was moderated by child trait anxiety. In addition, children with higher trait anxiety displayed a significant increase in observed child anxiety in the controlling condition. The pattern of results was maintained when differences in mothers' levels of negativity and habitual levels of control were accounted for. These findings are consistent with theories that suggest that controlling parenting is a risk factor in the development of childhood anxiety. Copyright 2010 Elsevier Ltd. All rights reserved.

  15. An experimental test of the role of control in spider fear.

    PubMed

    Healey, Andrew; Mansell, Warren; Tai, Sara

    2017-06-01

    It is well established that uncontrollable adverse experiences lead to increased distress, but the role of client control during psychological interventions such as exposure is less clear. Earlier studies reported inconsistent findings, most likely owing to variations in the way client control was manipulated, degree of exposure, the outcome variables chosen and the follow-up periods used. Importantly, studies to date had suggested to participants that approaching their fears was beneficial thereby biasing their choices and these studies had not measured change beyond the laboratory. We recruited 96 spider-fearful student participants (mean age=22; SD=5.9; Range=18-45; 86 female). The experimental design allowed full choice over their degree of exposure, and manipulated the degree of control as the extent to which their movement of a joystick influenced their virtual distance from a moving spider image. Those with high control were yoked with a low control counterpart to ensure equal amounts of exposure. Measures were elicited at baseline, post-exposure, and at follow-up. As predicted, compared to low control participants, those with high control over exposure approached closer toward a spider post-exposure and reported less spider avoidance after an average of 17days. No group differences were found in physiological or subjective distress during the task, nor in distress and dysfunction. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Comparative hydraulics of two fishery research circular tanks and recommendations for control of experimental bias

    USGS Publications Warehouse

    Odeh, M.; Schrock, R.M.; Gannam, A.

    2003-01-01

    Hydraulic characteristics inside two research circular tanks (1.5-m and 1.2-m diameter) with the same volume of water were studied to understand how they might affect experimental bias by influencing the behavior and development of juvenile fish. Water velocities inside each tank were documented extensively and flow behavior studied. Surface inflow to the 1.5-m tank created a highly turbulent and aerated surface, and produced unevenly distributed velocities within the tank. A low-flow velocity, or "dead" zone, persisted just upstream of the surface inflow. A single submerged nozzle in the 1.2-m tank created uniform flow and did not cause undue turbulence or introduce air. Flow behavior in the 1.5-m tank is believed to have negatively affected the feeding behavior and physiological development of a group of juvenile fall chinook salmon, Oncorhynchus tshawytscha. A new inflow nozzle design provided comparable flow behavior regardless of tank size and water depth. Maintaining similar hydraulic conditions inside tanks used for various biological purposes, including fish research, would minimize experimental bias caused by differences in flow behavior. Other sources of experimental bias are discussed and recommendations given for reporting and control of experimental conditions in fishery research tank experiments.

  17. Controlling and culturing diversity: experimental zoology before World War II and Vienna's Biologische Versuchsanstalt.

    PubMed

    Logan, Cheryl A; Brauckmann, Sabine

    2015-04-01

    Founded in Vienna in 1903, the Institute for Experimental Biology pioneered the application of experimental methods to living organisms maintained for sustained periods in captivity. Its Director, the zoologist Hans Przibram, oversaw until 1938, the attempt to integrate ontogeny with studies of inheritance using precise and controlled measurements of the impact of environmental influences on the emergence of form and function. In the early years, these efforts paralleled and even fostered the emergence of experimental biology in America. But fate intervened. Though the Institute served an international community, most of its resident scientists and staff were of Jewish ancestry. Well before the Nazis entered Austria in 1938, these men and women were being fired and driven out; some, including Przibram, were eventually killed. We describe the unprecedented facilities built and the topics addressed by the several departments that made up this Institute, stressing those most relevant to the establishment and success of the Journal of Experimental Zoology, which was founded just a year later. The Institute's diaspora left an important legacy in North America, perhaps best embodied by the career of the developmental neuroscientist Paul Weiss. © 2015 Wiley Periodicals, Inc.

  18. Inflammasomes make the case for littermate-controlled experimental design in studying host-microbiota interactions.

    PubMed

    Mamantopoulos, Michail; Ronchi, Francesca; McCoy, Kathy D; Wullaert, Andy

    2018-04-19

    Several human diseases are thought to evolve due to a combination of host genetic mutations and environmental factors that include alterations in intestinal microbiota composition termed dysbiosis. Although in some cases, host genetics may shape the gut microbiota and enable it to provoke disease, experimentally disentangling cause and consequence in such host-microbe interactions requires strict control over non-genetic confounding factors. Mouse genetic studies previously proposed Nlrp6/ASC inflammasomes as innate immunity regulators of the intestinal ecosystem. In contrast, using littermate-controlled experimental setups, we recently showed that Nlrp6/ASC inflammasomes do not alter the gut microbiota composition. Our analyses indicated that maternal inheritance and long-term separate housing are non-genetic confounders that preclude the use of non-littermate mice when analyzing host genetic effects on intestinal ecology. Here, we summarize and discuss our gut microbiota analyses in inflammasome-deficient mice for illustrating the importance of littermate experimental design in studying host-microbiota interactions.

  19. Flow-controlled expiration: a novel ventilation mode to attenuate experimental porcine lung injury.

    PubMed

    Goebel, U; Haberstroh, J; Foerster, K; Dassow, C; Priebe, H-J; Guttmann, J; Schumann, S

    2014-09-01

    Whereas the effects of various inspiratory ventilatory modifications in lung injury have extensively been studied, those of expiratory ventilatory modifications are less well known. We hypothesized that the newly developed flow-controlled expiration (FLEX) mode provides a means of attenuating experimental lung injury. Experimental acute respiratory distress syndrome was induced by i.v. injection of oleic acid in 15 anaesthetized and mechanically ventilated pigs. After established lung injury ([Formula: see text]ratio <27 kPa), animals were randomized to either a control group receiving volume-controlled ventilation (VCV) or a treatment group receiving VCV with additional FLEX (VCV+FLEX). At predefined times, lung mechanics and oxygenation were assessed. At the end of the experiment, the pigs were killed, and bronchoalveolar fluid and lung biopsies were taken. Expression of inflammatory cytokines was analysed in lung tissue and bronchoalveolar fluid. Lung injury score was determined on the basis of stained tissue samples. Compared with the control group (VCV; n=8), the VCV+FLEX group (n=7) demonstrated greater dynamic lung compliance and required less PEEP at comparable [Formula: see text] (both P<0.05), had lower regional lung wet-to-dry ratios and lung injury scores (both P<0.001), and showed less thickening of alveolar walls (an indicator of interstitial oedema) and de novo migration of macrophages into lung tissue (both P<0.001). The newly developed FLEX mode is able to attenuate experimental lung injury. FLEX could provide a novel means of lung-protective ventilation. © The Author [2014]. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  20. Experimental opto-mechanics with levitated nanoparticles: towards quantum control and thermodynamic cycles (Presentation Recording)

    NASA Astrophysics Data System (ADS)

    Kiesel, Nikolai; Blaser, Florian; Delic, Uros; Grass, David; Dechant, Andreas; Lutz, Eric; Bathaee, Marzieh; Aspelmeyer, Markus

    2015-08-01

    Combining optical levitation and cavity optomechanics constitutes a promising approach to prepare and control the motional quantum state of massive objects (>10^9 amu). This, in turn, would represent a completely new type of light-matter interface and has, for example, been predicted to enable experimental tests of macrorealistic models or of non-Newtonian gravity at small length scales. Such ideas have triggered significant experimental efforts to realizing such novel systems. To this end, we have recently successfully demonstrated cavity-cooling of a levitated sub-micron silica particle in a classical regime at a pressure of approximately 1mbar. Access to higher vacuum of approx. 10^-6 mbar has been demonstrated using 3D-feedback cooling in optical tweezers without cavity-coupling. Here we will illustrate our strategy towards trapping, 3D-cooling and quantum control of nanoparticles in ultra-high vacuum using cavity-based feedback cooling methods and clean particle loading with hollow-core photonic crystal fibers. We will also discuss the current experimental progress both in 3D-cavity cooling and HCPCF-based transport of nanoparticles. As yet another application of cavity-controlled levitated nanoparticles we will show how to implement a thermodynamic Sterling cycle operating in the underdamped regime. We present optimized protocols with respect to efficiency at maximum power in this little explored regime. We also show that the excellent level of control in our system will allow reproducing all relevant features of such optimized protocols. In a next step, this will enable studies of thermodynamics cycles in a regime where the quantization of the mechanical motion becomes relevant.

  1. Motivation in vigilance - Effects of self-evaluation and experimenter-controlled feedback.

    NASA Technical Reports Server (NTRS)

    Warm, J. S.; Kanfer, F. H.; Kuwada, S.; Clark, J. L.

    1972-01-01

    Vigilance experiments have been performed to study the relative efficiency of feedback operations in enhancing vigilance performance. Two feedback operations were compared - i.e., experimenter-controlled feedback in the form of knowledge of results (KR) regarding response times to signal detections, and subject-controlled feedback in the form of self-evaluation (SE) of response times to signal detections. The subjects responded to the aperiodic offset of a visual signal during a 1-hr vigil. Both feedback operations were found to enhance performance efficiency: subjects in the KR and SE conditions had faster response times than controls receiving no evaluative feedback. Moreover, the data of the KR and SE groups did not differ significantly from each other. The results are discussed in terms of the hypothesis that self-evaluation is a critical factor underlying the incentive value of KR in vigilance tasks.

  2. The experimental results of a self tuning adaptive controller using online frequency identification. [for Galileo spacecraft

    NASA Technical Reports Server (NTRS)

    Chiang, W.-W.; Cannon, R. H., Jr.

    1985-01-01

    A fourth-order laboratory dynamic system featuring very low structural damping and a noncolocated actuator-sensor pair has been used to test a novel real-time adaptive controller, implemented in a minicomputer, which consists of a state estimator, a set of state feedback gains, and a frequency-locked loop for real-time parameter identification. The adaptation algorithm employed can correct controller error and stabilize the system for more than 50 percent variation in the plant's natural frequency, compared with a 10 percent stability margin in frequency variation for a fixed gain controller having the same performance as the nominal plant condition. The very rapid convergence achievable by this adaptive system is demonstrated experimentally, and proven with simple, root-locus methods.

  3. Experimental Verification of Fully Decentralized Control Inspired by Plasmodium of True Slime Mold

    NASA Astrophysics Data System (ADS)

    Umedachi, Takuya; Takeda, Koichi; Nakagaki, Toshiyuki; Kobayashi, Ryo; Ishiguro, Akio

    This paper presents a fully decentralized control inspired by plasmodium of true slime mold and its validity using a soft-bodied amoeboid robot. The notable features of this paper are twofold: (1) the robot has truly soft and deformable body stemming from real-time tunable springs and a balloon, the former is utilized as an outer skin of the body and the latter serves as protoplasm; and (2) a fully decentralized control using coupled oscillators with completely local sensory feedback mechanism is realized by exploiting the long-distance physical interaction between the body parts induced by the law of conservation of protoplasmic mass. Experimental results show that this robot exhibits truly supple locomotion without relying on any hierarchical structure. The results obtained are expected to shed new light on design scheme for autonomous decentralized control system.

  4. Effects of virtual reality training on functional reaching movements in people with Parkinson's disease: a randomized controlled pilot trial.

    PubMed

    Ma, Hui-Ing; Hwang, Wen-Juh; Fang, Jing-Jing; Kuo, Jui-Kun; Wang, Ching-Yi; Leong, Iat-Fai; Wang, Tsui-Ying

    2011-10-01

    To investigate whether practising reaching for virtual moving targets would improve motor performance in people with Parkinson's disease. Randomized pretest-posttest control group design. A virtual reality laboratory in a university setting. Thirty-three adults with Parkinson's disease. The virtual reality training required 60 trials of reaching for fast-moving virtual balls with the dominant hand. The control group had 60 practice trials turning pegs with their non-dominant hand. Pretest and posttest required reaching with the dominant hand to grasp real stationary balls and balls moving at different speeds down a ramp. Success rates and kinematic data (movement time, peak velocity and percentage of movement time for acceleration phase) from pretest and posttest were recorded to determine the immediate transfer effects. Compared with the control group, the virtual reality training group became faster (F = 9.08, P = 0.005) and more forceful (F = 9.36, P = 0.005) when reaching for real stationary balls. However, there was no significant difference in success rate or movement kinematics between the two groups when reaching for real moving balls. A short virtual reality training programme improved the movement speed of discrete aiming tasks when participants reached for real stationary objects. However, the transfer effect was minimal when reaching for real moving objects.

  5. A randomised-controlled trial investigating potential underlying mechanisms of a functionality-based approach to improving women's body image.

    PubMed

    Alleva, Jessica M; Diedrichs, Phillippa C; Halliwell, Emma; Martijn, Carolien; Stuijfzand, Bobby G; Treneman-Evans, Georgia; Rumsey, Nichola

    2018-06-01

    Focusing on body functionality is a promising technique for improving women's body image. This study replicates prior research in a large novel sample, tests longer-term follow-up effects, and investigates underlying mechanisms of these effects (body complexity and body-self integration). British women (N = 261) aged 18-30 who wanted to improve their body image were randomised to Expand Your Horizon (three online body functionality writing exercises) or an active control. Trait body image was assessed at Pretest, Posttest, 1-week, and 1-month Follow-Up. To explore whether changes in body complexity and body-self integration 'buffer' the impact of negative body-related experiences, participants also completed beauty-ideal media exposure. Relative to the control, intervention participants experienced improved appearance satisfaction, functionality satisfaction, body appreciation, and body complexity at Posttest, and at both Follow-Ups. Neither body complexity nor body-self integration mediated intervention effects. Media exposure decreased state body satisfaction among intervention and control participants, but neither body complexity nor body-self integration moderated these effects. The findings underscore the value of focusing on body functionality for improving body image and show that effects persist one month post-intervention. Copyright © 2018 Elsevier Ltd. All rights reserved.

  6. Experimental system, and its evaluation for the control of surgically inducted infections

    NASA Technical Reports Server (NTRS)

    Tevebaugh, M. D.; Nelson, J. P.

    1972-01-01

    The effect is reported to design, fabricate, test and evaluate a prototype experimental system for the control of surgically induced infections. The purpose is to provide the cleanest possible environment within a hospital surgery room and eliminate contamination sources that could cause infections during surgery. The system design is described. The system provides for a portable laminar flow clean room, a full bubble helmet system with associated communications and ventilation subsystems for operating room personnel, and surgical gowns that minimize the migration of bacteria. The development test results consisting of portability, laminar flowrate, air flow pattern, electrostatic buildup, noise level, ventilation, human factors, electrical and material compatibility tests are summarized. The conclusions are that the experimental system is effective in reducing the airborne and wound contamination although the helmets and gowns may not be a significant part of this reduction. Definitive conclusions with regard to the infection rate cannot be made at this time.

  7. Nonpharmacologic control of essential hypertension in man: a critical review of the experimental literature.

    PubMed

    Frumkin, K; Nathan, R J; Prout, M F; Cohen, M C

    1978-06-01

    Many nonpharmacologic (behavioral) techniques are being proposed for the therapy of essential hypertension. The research in this area is reviewed and divided roughly into two categories: the biofeedback and relaxation methodologies. While feedback can be used to lower pressures during laboratory training sessions, studies designed to alter basal blood pressure levels with biofeedback have not yet been reported. The absence of evidence for such changes through biofeedback limits the usefulness of this technique in hypertension control. The various relaxation methods, such as yoga, transcendental meditation, progressive muscle relaxation, and others have shown more promise. With varying degrees of experimental vigor, many of these techniques have been associated with long-lasting changes in blood pressure. The strengths and weaknesses of the various authors' research designs, data and conclusions are discussed, and suggestions for further experimentation are offered.

  8. Indicated Cognitive-Behavioral Group Depression Prevention Compared to Bibliotherapy and Brochure Control: Acute Effects of an Effectiveness Trial with Adolescents

    PubMed Central

    Rohde, Paul; Stice, Eric; Shaw, Heather; Brière, Frédéric N.

    2014-01-01

    Objective Test whether a brief cognitive-behavioral (CB) group and bibliotherapy prevention reduce major depressive disorder onset, depressive symptoms, and secondary outcomes relative to brochure controls in adolescents with self-reported depressive symptoms when school personnel recruit participants and deliver the intervention. Method 378 adolescents (M age = 15.5, SD = 1.2; 68% female, 72% White) with elevated self-assessed depressive symptoms were randomized to a 6-session CB group, minimal contact CB bibliotherapy, or educational brochure control. Participants were assessed at pretest, posttest, and 6-month follow-up. Results CB group participants showed a significantly lower risk for major depressive disorder onset (0.8%) compared to both CB bibliotherapy (6.3%) and brochure control (6.5%; HR = 8.1 and 8.3; respectively). Planned contrasts indicated that CB group resulted in lower depressive symptom severity than brochure control at posttest (p = .03, d = .29) but not 6-month follow-up; differences between CB group and bibliotherapy were nonsignificant at posttest and 6-month follow-up. Condition effects were nonsignificant for social adjustment and substance use. Conclusions The finding that a brief CB group intervention delivered by real-world providers significantly reduced MDD onset relative to both brochure control and bibliotherapy is very encouraging, though effects on continuous outcome measures were small or nonsignificant and approximately half the magnitude of those found in efficacy research, potentially because the present sample reported lower initial depression. PMID:24099432

  9. Impact of a Simulated Clinical Day With Peer Coaching and Deliberate Practice: Promoting a Culture of Safety.

    PubMed

    Badowski, Donna M; Oosterhouse, Kimberly J

    Nursing education is challenged to shift from task-based proficiencies to higher level competencies with patient safety as a priority. Using a quasi-experimental pretest/posttest design, a simulation-based, peer-coached, deliberate practice clinical substitution was implemented to compare nursing students' knowledge, skills, and attitudes for promoting safety. Our findings demonstrated improved knowledge and skill acquisition in the intervention and control groups. The former trended toward improved team communication attitudes and enteral medication skill performance. Additional research with larger samples is needed to further investigate this innovative strategy.

  10. Tilted wheel satellite attitude control with air-bearing table experimental results

    NASA Astrophysics Data System (ADS)

    Inumoh, Lawrence O.; Forshaw, Jason L.; Horri, Nadjim M.

    2015-12-01

    Gyroscopic actuators for satellite control have attracted significant research interest over the years, but their viability for the control of small satellites has only recently started to become clear. Research on variable speed gyroscopic actuators has long been focused on single gimbal actuators; double gimbal actuators typically operate at constant wheel spin rate and allow tilt angle ranges far larger than the ranges needed to operate most satellite missions. This research examines a tilted wheel, a newly proposed type of inertial actuator that can generate torques in all three principal axes of a rigid satellite using a spinning wheel and a double tilt mechanism. The tilt mechanism tilts the angular momentum vector about two axes providing two degree of freedom control, while variation of the wheel speed provides the third. The equations of motion of the system lead to a singularity-free system during nominal operation avoiding the need for complex steering logic. This paper describes the hardware design of the tilted wheel and the experimental setup behind both standalone and spherical air-bearing tables used to test it. Experimental results from the air bearing table are provided with the results depicting the high performance capabilities of the proposed actuator in torque generation.

  11. Structural control and health monitoring of building structures with unknown ground excitations: Experimental investigation

    NASA Astrophysics Data System (ADS)

    He, Jia; Xu, You-Lin; Zhan, Sheng; Huang, Qin

    2017-03-01

    When health monitoring system and vibration control system both are required for a building structure, it will be beneficial and cost-effective to integrate these two systems together for creating a smart building structure. Recently, on the basis of extended Kalman filter (EKF), a time-domain integrated approach was proposed for the identification of structural parameters of the controlled buildings with unknown ground excitations. The identified physical parameters and structural state vectors were then utilized to determine the control force for vibration suppression. In this paper, the possibility of establishing such a smart building structure with the function of simultaneous damage detection and vibration suppression was explored experimentally. A five-story shear building structure equipped with three magneto-rheological (MR) dampers was built. Four additional columns were added to the building model, and several damage scenarios were then simulated by symmetrically cutting off these columns in certain stories. Two sets of earthquakes, i.e. Kobe earthquake and Northridge earthquake, were considered as seismic input and assumed to be unknown during the tests. The structural parameters and the unknown ground excitations were identified during the tests by using the proposed identification method with the measured control forces. Based on the identified structural parameters and system states, a switching control law was employed to adjust the current applied to the MR dampers for the purpose of vibration attenuation. The experimental results show that the presented approach is capable of satisfactorily identifying structural damages and unknown excitations on one hand and significantly mitigating the structural vibration on the other hand.

  12. Experimental Studies of Low-Pressure Turbine Flows and Flow Control

    NASA Technical Reports Server (NTRS)

    Volino, Ralph J.

    2012-01-01

    This report summarizes research performed in support of the NASA Glenn Research Center (GRC) Low-Pressure Turbine (LPT) Flow Physics Program. The work was performed experimentally at the U.S. Naval Academy faculties. The geometry corresponded to "Pak B" LPT airfoil. The test section simulated LPT flow in a passage. Three experimental studies were performed: (a) Boundary layer measurements for ten baseline cases under high and low freestream turbulence conditions at five Reynolds numbers of 25,000, 50,000, 100,000, 200,000, and 300,000, based on passage exit velocity and suction surface wetted length; (b) Passive flow control studies with three thicknesses of two-dimensional bars, and two heights of three-dimensional circular cylinders with different spanwise separations, at same flow conditions as the 10 baseline cases; (c) Active flow control with oscillating synthetic (zero net mass flow) vortex generator jets, for one case with low freestream turbulence and a low Reynolds number of 25,000. The Passive flow control was successful at controlling the separation problem at low Reynolds numbers, with varying degrees of success from case to case and varying levels of impact at higher Reynolds numbers. The active flow control successfully eliminated the large separation problem for the low Reynolds number case. Very detailed data was acquired using hot-wire anemometry, including single and two velocity components, integral boundary layer quantities, turbulence statistics and spectra, turbulent shear stresses and their spectra, and intermittency, documenting transition, separation and reattachment. Models were constructed to correlate the results. The report includes a summary of the work performed and reprints of the publications describing the various studies.

  13. Human factors requirements for telerobotic command and control: The European Space Agency experimental programme

    NASA Technical Reports Server (NTRS)

    Stone, Robert J.

    1991-01-01

    Space Telerobotics research, performed under contract to the European Space Agency (ESA), concerning the execution of human factors experiments, and ultimately leading to the development of a telerobotics test bed, has been carried out since 1985 by a British Consortium consisting of British Aerospace, the United Kingdom Atomic Energy Authority and, more recently, the UK National Advanced Robotics Research Centre. The principal aim of the first study of the series was to derive preliminary requirements for a teleoperation servicing system, with reference to two mission model scenarios. The first scenario introduced the problem of communications time delays, and their likely effect on the ground-based operator in control of a manipulator system on board an unmanned servicing vehicle in Low Earth Orbit. In the second scenario, the operator was located on the NASA Orbiter aft flight deck, supervising the control of a prototype manipulator in the 'servicing' of an experimental payload in the cargo bay area. Human factors analyses centered on defining the requirements for the teleoperator workstation, such as identifying basic ergonomic requirements for workstation and panel layouts, defining teleoperation strategies, developing alphanumeric and graphic screen formats for the supervision or direct control of the manipulator, and the potential applications of expert system technology. The second study for ESA involved an experimental appraisal of some of the important issues highlighted in the first study, for which relevant human factors data did not exist. Of central importance during the second study was the issue of communications time delays and their effect on the manual control of a teleoperated manipulator from a ground-based command and control station.

  14. An experimental microcomputer controlled system for synchronized pulsating anti-gravity suit.

    PubMed

    Moore, T W; Foley, J; Reddy, B R; Kepics, F; Jaron, D

    1987-07-01

    An experimental system to deliver synchronized external pressure pulsations to the lower body is described in this technical note. The system is designed using a microcomputer with a real time interface and an electro-pneumatic subsystem capable of delivering pressure pulses to a modified anti-G suit at a fast rate. It is versatile, containing many options for synchronizing, phasing and sequencing of the pressure pulsations and controlling the pressure level in the suit bladders. Details of its software and hardware are described along with the results of initial testing in a Dynamic Flight Simulator on human volunteers.

  15. Experimental investigation of control/display augmentation effects in a compensatory tracking task

    NASA Technical Reports Server (NTRS)

    Garg, Sanjay; Schmidt, David K.

    1988-01-01

    The effects of control/display augmentation on human performance and workload have been investigated for closed-loop, continuous-tracking tasks by a real-time, man-in-the-loop simulation study. The experimental results obtained indicate that only limited improvement in actual tracking performance is obtainable through display augmentation alone; with a very high level of display augmentation, tracking error will actually deteriorate. Tracking performance improves when status information is furnished for reasonable levels of display quickening; again, very high quickening levels lead to tracking error deterioration due to the incompatibility between the status information and the quickened signal.

  16. Digital simulation and experimental evaluation of the CO2-H(plus) control of pulmonary ventilation

    NASA Technical Reports Server (NTRS)

    Milhorn, H. T., Jr.; Reynolds, W. J.

    1972-01-01

    Previous models of the CO2-H(+) control of ventilation have been concerned either with the response to CO2 inhalation, or the response to perfusion of the surface of the medulla with mock cerebrospinal fluid having a high P sub CO2. Simulation of both responses with the same model has not been attempted. The purpose of the present study was two fold; first to develop such a model and, second, to obtain experimental data from human subjects for both developing this model and for evaluating this and future models.

  17. Experimental and analytical investigation of active loads control for aircraft landing gear

    NASA Technical Reports Server (NTRS)

    Morris, D. L.; Mcgehee, J. R.

    1983-01-01

    A series hydraulic, active loads control main landing gear from a light, twin-engine civil aircraft was investigated. Tests included landing impact and traversal of simulated runway roughness. It is shown that the active gear is feasible and very effective in reducing the force transmitted to the airframe. Preliminary validation of a multidegree of freedom active gear flexible airframe takeoff and landing analysis computer program, which may be used as a design tool for active gear systems, is accomplished by comparing experimental and computed data for the passive and active gears.

  18. Effect Sizes for Growth-Modeling Analysis for Controlled Clinical Trials in the Same Metric as for Classical Analysis

    PubMed Central

    Feingold, Alan

    2009-01-01

    The use of growth-modeling analysis (GMA)--including Hierarchical Linear Models, Latent Growth Models, and General Estimating Equations--to evaluate interventions in psychology, psychiatry, and prevention science has grown rapidly over the last decade. However, an effect size associated with the difference between the trajectories of the intervention and control groups that captures the treatment effect is rarely reported. This article first reviews two classes of formulas for effect sizes associated with classical repeated-measures designs that use the standard deviation of either change scores or raw scores for the denominator. It then broadens the scope to subsume GMA, and demonstrates that the independent groups, within-subjects, pretest-posttest control-group, and GMA designs all estimate the same effect size when the standard deviation of raw scores is uniformly used. Finally, it is shown that the correct effect size for treatment efficacy in GMA--the difference between the estimated means of the two groups at end of study (determined from the coefficient for the slope difference and length of study) divided by the baseline standard deviation--is not reported in clinical trials. PMID:19271847

  19. Enhancement of couples' communication and dyadic coping by a self-directed approach: a randomized controlled trial.

    PubMed

    Bodenmann, Guy; Hilpert, Peter; Nussbeck, Fridtjof W; Bradbury, Thomas N

    2014-08-01

    Although prevention of relationship distress and dissolution has potential to strengthen the well-being of partners and any children they are raising, dissemination of prevention programs can be limited because couples face many barriers to in-person participation. An alternative strategy, providing couples with an instructional DVD, is tested in the present study, in which 330 Caucasian couples (N = 660 participants; mean age: men 41.4 years, women 40.0 years) were randomly assigned to a DVD group without any further support, a DVD group with technical telephone coaching, or a wait-list control group. Couples completed questionnaires at pretest, posttest, and 3 and 6 months after completion of the intervention. Self-report measures of dyadic coping, communication quality, ineffective arguing, and relationship satisfaction were used to test whether the intervention groups improved in comparison with the control group. Women in both intervention groups increased in dyadic coping, reduced conflict behavior, and were more satisfied with their relationship 6 months after the intervention. Effects for men were mixed. Participants with poorer skills reported stronger improvement. Intimate relationships can, within limits, be positively influenced by a self-directed approach. Effective dissemination of principles underlying successful relationships can be facilitated through the use of emerging low-cost tools and technologies. PsycINFO Database Record (c) 2014 APA, all rights reserved.

  20. Experimental investigation of shaping disturbance observer design for motion control of precision mechatronic stages with resonances

    NASA Astrophysics Data System (ADS)

    Yang, Jin; Hu, Chuxiong; Zhu, Yu; Wang, Ze; Zhang, Ming

    2017-08-01

    In this paper, shaping disturbance observer (SDOB) is investigated for precision mechatronic stages with middle-frequency zero/pole type resonance to achieve good motion control performance in practical manufacturing situations. Compared with traditional standard disturbance observer (DOB), in SDOB a pole-zero cancellation based shaping filter is cascaded to the mechatronic stage plant to meet the challenge of motion control performance deterioration caused by actual resonance. Noting that pole-zero cancellation is inevitably imperfect and the controller may even consequently become unstable in practice, frequency domain stability analysis is conducted to find out how each parameter of the shaping filter affects the control stability. Moreover, the robust design criterion of the shaping filter, and the design procedure of SDOB, are both proposed to guide the actual design and facilitate practical implementation. The SDOB with the proposed design criterion is applied to a linear motor driven stage and a voice motor driven stage, respectively. Experimental results consistently validate the effectiveness nature of the proposed SDOB scheme in practical mechatronics motion applications. The proposed SDOB design actually could be an effective unit in the controller design for motion stages of mechanical manufacture equipments.

  1. Design and experimental validation of a simple controller for a multi-segment magnetic crawler robot

    NASA Astrophysics Data System (ADS)

    Kelley, Leah; Ostovari, Saam; Burmeister, Aaron B.; Talke, Kurt A.; Pezeshkian, Narek; Rahimi, Amin; Hart, Abraham B.; Nguyen, Hoa G.

    2015-05-01

    A novel, multi-segmented magnetic crawler robot has been designed for ship hull inspection. In its simplest version, passive linkages that provide two degrees of relative motion connect front and rear driving modules, so the robot can twist and turn. This permits its navigation over surface discontinuities while maintaining its adhesion to the hull. During operation, the magnetic crawler receives forward and turning velocity commands from either a tele-operator or high-level, autonomous control computer. A low-level, embedded microcomputer handles the commands to the driving motors. This paper presents the development of a simple, low-level, leader-follower controller that permits the rear module to follow the front module. The kinematics and dynamics of the two-module magnetic crawler robot are described. The robot's geometry, kinematic constraints and the user-commanded velocities are used to calculate the desired instantaneous center of rotation and the corresponding central-linkage angle necessary for the back module to follow the front module when turning. The commands to the rear driving motors are determined by applying PID control on the error between the desired and measured linkage angle position. The controller is designed and tested using Matlab Simulink. It is then implemented and tested on an early two-module magnetic crawler prototype robot. Results of the simulations and experimental validation of the controller design are presented.

  2. James Webb Space Telescope optical simulation testbed III: first experimental results with linear-control alignment

    NASA Astrophysics Data System (ADS)

    Egron, Sylvain; Lajoie, Charles-Philippe; Leboulleux, Lucie; N'Diaye, Mamadou; Pueyo, Laurent; Choquet, Élodie; Perrin, Marshall D.; Ygouf, Marie; Michau, Vincent; Bonnefois, Aurélie; Fusco, Thierry; Escolle, Clément; Ferrari, Marc; Hugot, Emmanuel; Soummer, Rémi

    2016-07-01

    The James Webb Space Telescope (JWST) Optical Simulation Testbed (JOST) is a tabletop experiment designed to study wavefront sensing and control for a segmented space telescope, including both commissioning and maintenance activities. JOST is complementary to existing testbeds for JWST (e.g. the Ball Aerospace Testbed Telescope TBT) given its compact scale and flexibility, ease of use, and colocation at the JWST Science and Operations Center. The design of JOST reproduces the physics of JWST's three-mirror anastigmat (TMA) using three custom aspheric lenses. It provides similar quality image as JWST (80% Strehl ratio) over a field equivalent to a NIRCam module, but at 633 nm. An Iris AO segmented mirror stands for the segmented primary mirror of JWST. Actuators allow us to control (1) the 18 segments of the segmented mirror in piston, tip, tilt and (2) the second lens, which stands for the secondary mirror, in tip, tilt and x, y, z positions. We present the full linear control alignment infrastructure developed for JOST, with an emphasis on multi-field wavefront sensing and control. Our implementation of the Wavefront Sensing (WFS) algorithms using phase diversity is experimentally tested. The wavefront control (WFC) algorithms, which rely on a linear model for optical aberrations induced by small misalignments of the three lenses, are tested and validated on simulations.

  3. Experimental power spectral density analysis for mid- to high-spatial frequency surface error control.

    PubMed

    Hoyo, Javier Del; Choi, Heejoo; Burge, James H; Kim, Geon-Hee; Kim, Dae Wook

    2017-06-20

    The control of surface errors as a function of spatial frequency is critical during the fabrication of modern optical systems. A large-scale surface figure error is controlled by a guided removal process, such as computer-controlled optical surfacing. Smaller-scale surface errors are controlled by polishing process parameters. Surface errors of only a few millimeters may degrade the performance of an optical system, causing background noise from scattered light and reducing imaging contrast for large optical systems. Conventionally, the microsurface roughness is often given by the root mean square at a high spatial frequency range, with errors within a 0.5×0.5  mm local surface map with 500×500 pixels. This surface specification is not adequate to fully describe the characteristics for advanced optical systems. The process for controlling and minimizing mid- to high-spatial frequency surface errors with periods of up to ∼2-3  mm was investigated for many optical fabrication conditions using the measured surface power spectral density (PSD) of a finished Zerodur optical surface. Then, the surface PSD was systematically related to various fabrication process parameters, such as the grinding methods, polishing interface materials, and polishing compounds. The retraceable experimental polishing conditions and processes used to produce an optimal optical surface PSD are presented.

  4. Can jurors recognize missing control groups, confounds, and experimenter bias in psychological science?

    PubMed

    McAuliff, Bradley D; Kovera, Margaret Bull; Nunez, Gabriel

    2009-06-01

    This study examined the ability of jury-eligible community members (N = 248) to detect internal validity threats in psychological science presented during a trial. Participants read a case summary in which an expert testified about a study that varied in internal validity (valid, missing control group, confound, and experimenter bias) and ecological validity (high, low). Ratings of expert evidence quality and expert credibility were higher for the valid versus missing control group versions only. Internal validity did not influence verdict or ratings of plaintiff credibility and no differences emerged as a function of ecological validity. Expert evidence quality, expert credibility, and plaintiff credibility were positively correlated with verdict. Implications for the scientific reasoning literature and for trials containing psychological science are discussed.

  5. Experimental Investigation of Normal Shock Boundary-Layer Interaction with Hybrid Flow Control

    NASA Technical Reports Server (NTRS)

    Vyas, Manan A.; Hirt, Stefanie M.; Anderson, Bernhard H.

    2012-01-01

    Hybrid flow control, a combination of micro-ramps and micro-jets, was experimentally investigated in the 15x15 cm Supersonic Wind Tunnel (SWT) at the NASA Glenn Research Center. Full factorial, a design of experiments (DOE) method, was used to develop a test matrix with variables such as inter-ramp spacing, ramp height and chord length, and micro-jet injection flow ratio. A total of 17 configurations were tested with various parameters to meet the DOE criteria. In addition to boundary-layer measurements, oil flow visualization was used to qualitatively understand shock induced flow separation characteristics. The flow visualization showed the normal shock location, size of the separation, path of the downstream moving counter-rotating vortices, and corner flow effects. The results show that hybrid flow control demonstrates promise in reducing the size of shock boundary-layer interactions and resulting flow separation by means of energizing the boundary layer.

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

    PubMed

    Cairns, David A

    2011-03-01

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

  7. Flow Control Under Low-Pressure Turbine Conditions Using Pulsed Jets: Experimental Data Archive

    NASA Technical Reports Server (NTRS)

    Volino, Ralph J.; Ibrahim, Mounir B.

    2012-01-01

    This publication is the final report of research performed under an NRA/Cooperative Interagency Agreement, and includes a supplemental CD-ROM with detailed data. It is complemented by NASA/CR-2012-217416 and NASA/CR-2012-217417 which include a Ph.D. Dissertation and an M.S. thesis respectively, performed under this contract. In this study the effects of unsteady wakes and flow control using vortex generator jets (VGJs) were studied experimentally and computationally on the flow over the L1A low pressure turbine (LPT) airfoil. The experimental facility was a six passage linear cascade in a low speed wind tunnel at the U.S. Naval Academy. In parallel, computational work using the commercial code FLUENT (ANSYS, Inc.) was performed at Cleveland State University, using Unsteady Reynolds Averaged Navier Stokes (URANS) and Large Eddy Simulations (LES) methods. In the first phase of the work, the baseline flow was documented under steady inflow conditions without flow control. URANS calculations were done using a variety of turbulence models. In the second phase of the work, flow control was added using steady and pulsed vortex generator jets. The VGJs successfully suppressed separation and reduced aerodynamic losses. Pulsed operation was more effective and mass flow requirements are very low. Numerical simulations of the VGJs cases showed that URANS failed to capture the effect of the jets. LES results were generally better. In the third phase, effects of unsteady wakes were studied. Computations with URANS and LES captured the wake effect and generally predicted separation and reattachment to match the experiments. Quantitatively the results were mixed. In the final phase of the study, wakes and VGJs were combined and synchronized using various timing schemes. The timing of the jets with respect to the wakes had some effect, but in general once the disturbance frequency was high enough to control separation, the timing was not very important. This is the supplemental CD-ROM

  8. Virtual Reality for Enhanced Ecological Validity and Experimental Control in the Clinical, Affective and Social Neurosciences.

    PubMed

    Parsons, Thomas D

    2015-01-01

    An essential tension can be found between researchers interested in ecological validity and those concerned with maintaining experimental control. Research in the human neurosciences often involves the use of simple and static stimuli lacking many of the potentially important aspects of real world activities and interactions. While this research is valuable, there is a growing interest in the human neurosciences to use cues about target states in the real world via multimodal scenarios that involve visual, semantic, and prosodic information. These scenarios should include dynamic stimuli presented concurrently or serially in a manner that allows researchers to assess the integrative processes carried out by perceivers over time. Furthermore, there is growing interest in contextually embedded stimuli that can constrain participant interpretations of cues about a target's internal states. Virtual reality environments proffer assessment paradigms that combine the experimental control of laboratory measures with emotionally engaging background narratives to enhance affective experience and social interactions. The present review highlights the potential of virtual reality environments for enhanced ecological validity in the clinical, affective, and social neurosciences.

  9. Virtual Reality for Enhanced Ecological Validity and Experimental Control in the Clinical, Affective and Social Neurosciences

    PubMed Central

    Parsons, Thomas D.

    2015-01-01

    An essential tension can be found between researchers interested in ecological validity and those concerned with maintaining experimental control. Research in the human neurosciences often involves the use of simple and static stimuli lacking many of the potentially important aspects of real world activities and interactions. While this research is valuable, there is a growing interest in the human neurosciences to use cues about target states in the real world via multimodal scenarios that involve visual, semantic, and prosodic information. These scenarios should include dynamic stimuli presented concurrently or serially in a manner that allows researchers to assess the integrative processes carried out by perceivers over time. Furthermore, there is growing interest in contextually embedded stimuli that can constrain participant interpretations of cues about a target’s internal states. Virtual reality environments proffer assessment paradigms that combine the experimental control of laboratory measures with emotionally engaging background narratives to enhance affective experience and social interactions. The present review highlights the potential of virtual reality environments for enhanced ecological validity in the clinical, affective, and social neurosciences. PMID:26696869

  10. Experimental investigation of active rib stitch knitted architecture for flow control applications

    NASA Astrophysics Data System (ADS)

    Abel, Julianna M.; Mane, Poorna; Pascoe, Benjamin; Luntz, Jonathan; Brei, Diann

    2010-04-01

    Actively manipulating flow characteristics around the wing can enhance the high-lift capability and reduce drag; thereby, increasing fuel economy, improving maneuverability and operation over diverse flight conditions which enables longer, more varied missions. Active knits, a novel class of cellular structural smart material actuator architectures created by continuous, interlocked loops of stranded active material, produce distributed actuation that can actively manipulate the local surface of the aircraft wing to improve flow characteristics. Rib stitch active knits actuate normal to the surface, producing span-wise discrete periodic arrays that can withstand aerodynamic forces while supplying the necessary displacement for flow control. This paper presents a preliminary experimental investigation of the pressuredisplacement actuation performance capabilities of a rib stitch active knit based upon shape memory alloy (SMA) wire. SMA rib stitch prototypes in both individual form and in stacked and nestled architectures were experimentally tested for their quasi-static load-displacement characteristics, verifying the parallel and series relationships of the architectural configurations. The various configurations tested demonstrated the potential of active knits to generate the required level of distributed surface displacements while under aerodynamic level loads for various forms of flow control.

  11. Transport of fluorobenzoate tracers in a vegetated hydrologic control volume: 1. Experimental results

    NASA Astrophysics Data System (ADS)

    Queloz, Pierre; Bertuzzo, Enrico; Carraro, Luca; Botter, Gianluca; Miglietta, Franco; Rao, P. S. C.; Rinaldo, Andrea

    2015-04-01

    This paper reports about the experimental evidence collected on the transport of five fluorobenzoate tracers injected under controlled conditions in a vegetated hydrologic volume, a large lysimeter (fitted with load cells, sampling ports, and an underground chamber) where two willows prompting large evapotranspiration fluxes had been grown. The relevance of the study lies in the direct and indirect measures of the ways in which hydrologic fluxes, in this case, evapotranspiration from the upper surface and discharge from the bottom drainage, sample water and solutes in storage at different times under variable hydrologic forcings. Methods involve the accurate control of hydrologic inputs and outputs and a large number of suitable chemical analyses of water samples in discharge waters. Mass extraction from biomass has also been performed ex post. The results of the 2 year long experiment established that our initial premises on the tracers' behavior, known to be sorption-free under saturated conditions which we verified in column leaching tests, were unsuitable as large differences in mass recovery appeared. Issues on reactivity thus arose and were addressed in the paper, in this case attributed to microbial degradation and solute plant uptake. Our results suggest previously unknown features of fluorobenzoate compounds as hydrologic tracers, potentially interesting for catchment studies owing to their suitability for distinguishable multiple injections, and an outlook on direct experimental closures of mass balance in hydrologic transport volumes involving fluxes that are likely to sample differently stored water and solutes.

  12. Differences in cytokinin control on cellular dynamics of zucchini cotyledons cultivated in two experimental systems.

    PubMed

    Stoynova-Bakalova, E; Petrov, P; Gigova, L; Ivanova, N

    2011-01-01

    The effect of endogenous cytokinins on the pattern of palisade cell division post-germination does not depend on the conditions of cotyledon development -in planta (attached to seedlings) or in vitro (isolated from dry zucchini seeds and cultured on water). In cotyledons originating from 4-day-old seedlings (experimental system 1), exogenous cytokinin temporarily (in the first 2 day of cultivation) enhanced post-mitotic cell enlargement of palisade cells, mainly due to enhanced water uptake and use of cell storage compounds, all of which lead to cotyledon senescence. Cytokinin is not able to resume the completed palisade cell division on day 5. As a result, the number of cells and the final areas of treated and control cotyledons are quite similar. By contrast, the effects of cytokinin on cotyledons isolated from dry seeds (experimental system 2) are better expressed, promoting an increase in number of palisade cells accompanied by additional cotyledon area enlargement. However, the prolonged post-mitotic cell expansion in control cotyledons compensates for the reduced speed of cell growth and division activity and decreases differences in final cotyledon area between treatments. The results define cell division as the primary target of cytokinin stimulation in cotyledon tissues competent for division, and determine the temporal patterns of palisade cell cycling related to cotyledon age. This knowledge permits a better choice of experimental system to study effects on cell proliferation and cell growth, as well as cell enlargement and senescence-related events using physiologically homogeneous material. © 2010 German Botanical Society and The Royal Botanical Society of the Netherlands.

  13. [Reducing stress levels and anxiety in primary-care physicians through training and practice of a mindfulness meditation technique].

    PubMed

    Franco Justo, Clemente

    2010-11-01

    To check the effectiveness of a mindfulness development meditation technique on stress and anxiety in a group of primary-care physicians. Quasi-experimental with pretest/posttest/follow-up measurements in a control group and an experimental group. SITE: University of Almeria. 38 primary-care physicians enrolled in a Teaching Aptitude Course (CAP). An experimental group and a control group were formed with 19 participants in each. The experimental group took a psycho-educational meditation program for training and practice in mindfulness. The Perceived Stress Scale (PSS), the Strain Questionnaire and the State-Trait Anxiety Questionnaire were used to measure stress and anxiety levels. A comparative statistical analysis was performed using the Mann-Whitney non-parametric U test, finding a significant reduction in all the primary-care physician stress and anxiety variables in the experimental group compared to the control group in pretest-posttest and follow-up tests. The results of this study support the effectiveness of mindfulness development meditation techniques in decreasing stress and anxiety in primary-care physicians. Nevertheless, the study shows various limitations that would have to be corrected in successive studies to bring more validity to the results. Copyright © 2009 Elsevier España, S.L. All rights reserved.

  14. The preliminary effect of a parenting program for Korean American mothers: a randomized controlled experimental study.

    PubMed

    Kim, Eunjung; Cain, Kevin C; Webster-Stratton, Carolyn

    2008-09-01

    Traditional Korean American discipline is characterized by a lack of expression of affection and use of harsh discipline. The purpose of this study was to pilot test the effect of the Incredible Years Parenting Program among Korean American mothers. A randomized controlled experimental study design was used; 29 first-generation Korean American mothers of young children (3-8 years old) were randomly assigned to intervention (n=20) and control (n=9) groups. Intervention group mothers received a 12-week parenting program. Control group mothers did not receive the intervention. Mothers reported on discipline styles (positive, appropriate, and harsh), level of acculturation, and their child's outcomes (behavioral problems and social competence) at pre-, post-, and 1-year follow-up intervals. After completing the program, intervention group mothers significantly increased use of positive discipline as compared to control group mothers. Among intervention group mothers, high-acculturated mothers significantly increased appropriate discipline whereas low-acculturated mothers significantly decreased harsh discipline. In the 1-year follow-up, intervention group mothers maintained the significant effect for positive discipline. Providing this program appears to be a promising way of promoting positive discipline among Korean American mothers.

  15. Development of a complex experimental system for controlled ecological life support technique

    NASA Astrophysics Data System (ADS)

    Guo, S.; Tang, Y.; Zhu, J.; Wang, X.; Feng, H.; Ai, W.; Qin, L.; Deng, Y.

    A complex experimental system for controlled ecological life support technique can be used as a test platform for plant-man integrated experiments and material close-loop experiments of the controlled ecological life support system CELSS Based on lots of plan investigation plan design and drawing design the system was built through the steps of processing installation and joined debugging The system contains a volume of about 40 0m 3 its interior atmospheric parameters such as temperature relative humidity oxygen concentration carbon dioxide concentration total pressure lighting intensity photoperiod water content in the growing-matrix and ethylene concentration are all monitored and controlled automatically and effectively Its growing system consists of two rows of racks along its left-and-right sides separately and each of which holds two up-and-down layers eight growing beds hold a total area of about 8 4m 2 and their vertical distance can be adjusted automatically and independently lighting sources consist of both red and blue light-emitting diodes Successful development of the test platform will necessarily create an essential condition for next large-scale integrated study of controlled ecological life support technique

  16. Numerical and Experimental Investigation of Turbulent Transport Control via Shaping of Radial Plasma Flow Profiles

    SciTech Connect

    Gilmore, Mark Allen

    Turbulence, and turbulence-driven transport are ubiquitous in magnetically confined plasmas, where there is an intimate relationship between turbulence, transport, instability driving mechanisms (such as gradients), plasma flows, and flow shear. Though many of the detailed physics of the interrelationship between turbulence, transport, drive mechanisms, and flow remain unclear, there have been many demonstrations that transport and/or turbulence can be suppressed or reduced via manipulations of plasma flow profiles. This is well known in magnetic fusion plasmas [e.g., high confinement mode (H-mode) and internal transport barriers (ITB’s)], and has also been demonstrated in laboratory plasmas. However, it may be that themore » levels of particle transport obtained in such cases [e.g. H-mode, ITB’s] are actually lower than is desirable for a practical fusion device. Ideally, one would be able to actively feedback control the turbulent transport, via manipulation of the flow profiles. The purpose of this research was to investigate the feasibility of using both advanced model-based control algorithms, as well as non-model-based algorithms, to control cross-field turbulence-driven particle transport through appropriate manipulation of radial plasma flow profiles. The University of New Mexico was responsible for the experimental portion of the project, while our collaborators at the University of Montana provided plasma transport modeling, and collaborators at Lehigh University developed and explored control methods.« less

  17. An Experimental Database for Conventional and Alternate Control Concepts on the HSR 1.675% Reference H Model

    NASA Technical Reports Server (NTRS)

    McMillin, Naomi; Allen, Jerry; Erickson, Gary; Campbell, Jim; Mann, Mike; Kubiatko, Paul; Yingling, David; Mason, Charlie

    1999-01-01

    The objective was to experimentally evaluate the longitudinal and lateral-directional stability and control characteristics of the Reference H configuration at supersonic and transonic speeds. A series of conventional and alternate control devices were also evaluated at supersonic and transonic speeds. A database on the conventional and alternate control devices was to be created for use in the HSR program.

  18. An Experimental Comparison of Two Methods Of Teaching Numerical Control Manual Programming Concepts; Visual Media Versus Hands-On Equipment.

    ERIC Educational Resources Information Center

    Biekert, Russell

    Accompanying the rapid changes in technology has been a greater dependence on automation and numerical control, which has resulted in the need to find ways of preparing programers for industrial machines using numerical control. To compare the hands-on equipment method and a visual media method of teaching numerical control, an experimental and a…

  19. Effectiveness of Massage Therapy and Abdominal Hypopressive Gymnastics in Nonspecific Chronic Low Back Pain: A Randomized Controlled Pilot Study

    PubMed Central

    Jiménez-Rejano, J. J.; Chillón-Martínez, R.; Gómez-Benítez, M. A.; De-La-Casa-Almeida, M.

    2018-01-01

    Background There are a great number of interventions in physiotherapy, but with little evidence of their effectiveness in chronic low back pain. Therefore, this study assesses effectiveness of Massage Therapy and Abdominal Hypopressive Gymnastics and the combination of both to decrease pain and lumbar disability while increasing joint mobility and quality of life in patients with chronic nonspecific low back pain. Methods A randomized, single-blinded, controlled, clinical trial with sample (n = 27) was comprised of patients between 20 and 65 years, diagnosed with pain of mechanical origin characterized by having a duration of at least 12 weeks and no serious complications. Each group received 8 interventions of 30 minutes. Results Friedman ANOVA test obtained statistically significant differences of Oswestry, NRS, and Schober variables (p < 0.05) in the three measurements (pretest, posttest 1, and posttest 2), in each individual group. ANOVA Kruskal-Wallis test was used for comparison between groups, and Oswestry Disability values were significantly higher (p = 0.024) in the group receiving both treatments. Conclusion Both individual groups reduce pain levels, improve disability, and increase the flexibility of the lumbar spine. The combination therapy provides greater benefits in terms of lumbar disability. This study is registered on March 8, 2016, with NCT02721914. PMID:29681973

  20. Auricular Acupressure Combined with an Internet-Based Intervention or Alone for Primary Dysmenorrhea: A Control Study

    PubMed Central

    Yeh, Mei-Ling; Hung, Yu-Ling; Lin, Jaung-Geng

    2013-01-01

    Background. Primary dysmenorrhea is prevalent in adolescents and young women. Menstrual pain and distress causes poor school performance and physiological damage. Auricular acupressure can be used to treat these symptoms, and Internet-based systems are a flexible way of communicating and delivering the relevant information. Objective. This study investigates the effects of auricular acupressure (AA) alone and combined with an interactive Internet-based (II) intervention for the management of menstrual pain and self-care of adolescents with primary dysmenorrhea. Design. This study adopts a pretest/posttest control research design with a convenience sample of 107 participants. Results. The outcomes were measured using the short-form McGill pain questionnaire (SF-MPQ), visual analogue scale (VAS), menstrual distress questionnaire (MDQ), and adolescent dysmenorrheic self-care scale (ADSCS). Significant differences were found in ADSCS scores between the groups, and in SF-MPQ, VAS, MDQ, and ADSCS scores for each group. Conclusion. Auricular acupressure alone and a combination of auricular acupressure and interactive Internet both reduced menstrual pain and distress for primary dysmenorrhea. Auricular acupressure combined with interactive Internet instruction is better than auricular acupuncture alone in improving self-care behaviors. PMID:23653661

  1. Effectiveness of Massage Therapy and Abdominal Hypopressive Gymnastics in Nonspecific Chronic Low Back Pain: A Randomized Controlled Pilot Study.

    PubMed

    Bellido-Fernández, L; Jiménez-Rejano, J J; Chillón-Martínez, R; Gómez-Benítez, M A; De-La-Casa-Almeida, M; Rebollo-Salas, M

    2018-01-01

    There are a great number of interventions in physiotherapy, but with little evidence of their effectiveness in chronic low back pain. Therefore, this study assesses effectiveness of Massage Therapy and Abdominal Hypopressive Gymnastics and the combination of both to decrease pain and lumbar disability while increasing joint mobility and quality of life in patients with chronic nonspecific low back pain. A randomized, single-blinded, controlled, clinical trial with sample ( n = 27) was comprised of patients between 20 and 65 years, diagnosed with pain of mechanical origin characterized by having a duration of at least 12 weeks and no serious complications. Each group received 8 interventions of 30 minutes. Friedman ANOVA test obtained statistically significant differences of Oswestry, NRS, and Schober variables ( p < 0.05) in the three measurements (pretest, posttest 1, and posttest 2), in each individual group. ANOVA Kruskal-Wallis test was used for comparison between groups, and Oswestry Disability values were significantly higher ( p = 0.024) in the group receiving both treatments. Both individual groups reduce pain levels, improve disability, and increase the flexibility of the lumbar spine. The combination therapy provides greater benefits in terms of lumbar disability. This study is registered on March 8, 2016, with NCT02721914.

  2. Correlates of two experimental tests with performance in the FAA Academy air traffic control nonradar screen program.

    DOT National Transportation Integrated Search

    1990-08-01

    This study was designed to determine the relationships among experimental tests, the tests currently used to select entrants into the FAA's Air Traffic Control Specialist (ATCS) Academy Nonradar Screening Program, and Academy success. A battery of pa...

  3. Interactive hazards education program for youth in a low SES community: a quasi-experimental pilot study.

    PubMed

    Webb, Michelle; Ronan, Kevin R

    2014-10-01

    A pilot study of an interactive hazards education program was carried out in Canberra (Australia), with direct input from youth participants. Effects were evaluated in relation to youths' interest in disasters, motivation to prepare, risk awareness, knowledge indicators, perceived preparedness levels, planning and practice for emergencies, and fear and anxiety indicators. Parents also provided ratings, including of actual home-based preparedness activities. Using a single group pretest-posttest with benchmarking design, a sample of 20 youths and their parents from a low SES community participated. Findings indicated beneficial changes on a number of indicators. Preparedness indicators increased significantly from pre- to posttest on both youth (p < 0.01) and parent ratings (p < 0.01). Parent ratings reflected an increase of just under six home-based preparedness activities. Youth knowledge about disaster mitigation also was seen to increase significantly (p < 0.001), increasing 39% from pretest levels. While personalized risk perceptions significantly increased (p < 0.01), anxiety and worry levels were seen either not to change (generalized anxiety, p > 0.05) or to reduce between pre- and posttest (hazards-specific fears, worry, and distress, ps ranged from p < 0.05 to < 0.001). In terms of predictors of preparedness, a number of variables were found to predict posttest preparedness levels, including information searching done by participants between education sessions. These pilot findings are the first to reflect quasi-experimental outcomes for a youth hazards education program carried out in a setting other than a school that focused on a sample of youth from a low SES community. © 2014 Society for Risk Analysis.

  4. A Quasi-experimental outcomes analysis of a psychoeducation intervention for pregnant women with abuse-related posttraumatic stress.

    PubMed

    Rowe, Heather; Sperlich, Mickey; Cameron, Heather; Seng, Julia

    2014-01-01

    To test the effectiveness of a trauma-specific, psychoeducational intervention for pregnant women with a history of childhood maltreatment on six intrapartum and postpartum psychological outcomes. Quasi-experimental study comparing women from a single-group, pretest-posttest pilot intervention study with women matched from a prospective observational study. Rural and university-based prenatal clinics. Pregnant women entered the study by responding to an advertisement or by referral from a maternity care provider. Women could take part whether or not they met posttraumatic stress disorder diagnostic criteria. Outcomes data exist for 17 pilot intervention study participants and 43 matched observational study participants. Participants in the observational study received usual care. Participants in the pilot intervention study received usual care plus the intervention, a fully manualized, self-study program supported by weekly phone tutoring sessions with a health professional. The National Women's Study PTSD Module, the Peritraumatic Dissociation Experience Questionnaire, the Perception of Care Questionnaire, the Postpartum Depression Screening Scale, the Postpartum Bonding Questionnaire, and a semantic differential appraisal of the labor experience. Participants in the intervention study had better scores on all measures. Differences in means between participants in the intervention study and participants in the observational study equated to medium effect sized for dissociation during labor, rating of labor experience, and perception of care in labor and small effect sizes for postpartum posttraumatic stress disorder (PTSD) symptoms, postpartum depression symptoms, and motherinfant bonding. This trauma-specific intervention reaches and benefits pregnant women with a history of childhood maltreatment. © 2014 AWHONN, the Association of Women's Health, Obstetric and Neonatal Nurses.

  5. A quasi-experimental outcomes analysis of a psychoeducation intervention for pregnant women with abuse-related posttraumatic stress

    PubMed Central

    Rowe, Heather; Sperlich, Mickey; Seng, Julia S.

    2015-01-01

    Objective To test the effectiveness of a trauma-specific psycho-educational intervention for pregnant women with a history of childhood maltreatment on six intrapartum and postpartum psychological outcomes. Design Quasi-experimental study comparing women from a single-group pretest-posttest pilot intervention study with women matched from a prospective observational study. Setting Rural and university-based prenatal clinics. Participants Pregnant women entered the study by responding to an advertisement or by referral from a maternity care provider. Women could take part whether or not they met posttraumatic stress disorder diagnostic criteria. Outcomes data exist for 17 pilot intervention study participants and 43 matched observational study participants. Interventions Participants in the observational study received usual care. Participants in the pilot intervention study received usual care plus the intervention, a fully manualized self-study program supported by weekly phone tutoring sessions with a health professional. Main Outcome Measures The National Women’s Study PTSD Module; The Peritraumatic Dissociation Experience Questionnaire); The Perception of Care Questionnaire; The Postpartum Depression Screening Scale; The Postpartum Bonding Questionnaire; and a semantic differential appraisal of the labor experience. Results Participants in the intervention study had better scores on all measures. Differences in means between participants in the intervention study and participants in the observational study equated to medium effect sized for dissociation during labor, rating of labor experience, and perception of care in labor, and small effect sizes for postpartum PTSD symptoms, postpartum depression symptoms, and mother-infant bonding. Conclusion This trauma-specific intervention reaches and benefits pregnant women with a history of childhood maltreatment. PMID:24754455

  6. Active control of counter-rotating open rotor interior noise in a Dornier 728 experimental aircraft

    NASA Astrophysics Data System (ADS)

    Haase, Thomas; Unruh, Oliver; Algermissen, Stephan; Pohl, Martin

    2016-08-01

    The fuel consumption of future civil aircraft needs to be reduced because of the CO2 restrictions declared by the European Union. A consequent lightweight design and a new engine concept called counter-rotating open rotor are seen as key technologies in the attempt to reach this ambitious goals. Bearing in mind that counter-rotating open rotor engines emit very high sound pressures at low frequencies and that lightweight structures have a poor transmission loss in the lower frequency range, these key technologies raise new questions in regard to acoustic passenger comfort. One of the promising solutions for the reduction of sound pressure levels inside the aircraft cabin are active sound and vibration systems. So far, active concepts have rarely been investigated for a counter-rotating open rotor pressure excitation on complex airframe structures. Hence, the state of the art is augmented by the preliminary study presented in this paper. The study shows how an active vibration control system can influence the sound transmission of counter-rotating open rotor noise through a complex airframe structure into the cabin. Furthermore, open questions on the way towards the realisation of an active control system are addressed. In this phase, an active feedforward control system is investigated in a fully equipped Dornier 728 experimental prototype aircraft. In particular, the sound transmission through the airframe, the coupling of classical actuators (inertial and piezoelectric patch actuators) into the structure and the performance of the active vibration control system with different error sensors are investigated. It can be shown that the active control system achieves a reduction up to 5 dB at several counter-rotating open rotor frequencies but also that a better performance could be achieved through further optimisations.

  7. Experimental study of the active control applied to the flow past a backward facing ramp

    NASA Astrophysics Data System (ADS)

    Hlevca, Dan; Gilliéron, Patrick; Grasso, Francesco

    2018-03-01

    An experimental study of open loop active flow control on a backward facing ramp is presented. The ramp has finite span and a slant angle of 25°. Wind tunnel experiments were performed both for the uncontrolled and the controlled cases where time periodic forcing by pulsed jets is considered. The control system exploits an electro-magnetic valve system to generate pulsed jets with an operating frequency and duty cycle ranging, respectively, between 50 and 250 Hz and between 25 and 60%. A parametric study was carried out for three different freestream velocities and varying the frequency of the pulsed jets and the duty cycle. The control strategy relies on the injection of periodic perturbations before separation at the edge of the slant, considering various combinations of frequencies and duty cycles while keeping constant the blowing time for every Reynolds number, so as to excite the flow with the same jet structure over different actuation cycle extents. The receptivity of the flow to periodic forcing was assessed by characterizing mean and unsteady flow properties, turbulence statistics and flow topology. The study focused on the impact of control on reattachement and showed that the flow locks with excitation frequencies typical of initial Kelvin-Helmholtz instabilities. However, the flow was found to respond to any injected unsteady perturbation locking to the forcing frequencies and the extent of the region where locking occurs was found to be of the order of a few slant heights. A relaxation process was observed and the flow was found to relax past the slant trailing edge toward frequencies close to the natural ones.

  8. An experimental therapeutics test of whether adding dissonance-induction activities improves the effectiveness of a selective obesity and eating disorder prevention program.

    PubMed

    Stice, E; Rohde, P; Shaw, H; Gau, J M

    2018-03-01

    Compare the Healthy Weight obesity and eating disorder prevention program, which promotes participant-driven gradual lifestyle changes to bring energy intake and expenditure into balance, to a new intervention, Project Health, which adds activities to create cognitive dissonance about unhealthy eating, a sedentary lifestyle, and excess body fat, and an obesity education video-control condition. College students at risk for both outcomes because of weight concerns (N=364, 72% female) were randomized to condition, completing pretest, posttest, and 6, 12 and 24-month follow-up assessments. Project Health participants showed significantly smaller increases in measured body mass index (BMI) through 2-year follow-up than both Healthy Weight participants and controls (both d=-0.18), and significantly lower onset of overweight/obesity over 2-year follow-up than Healthy Weight participants and controls (13 vs 21% and 22%). Healthy Weight and Project Health participants showed significantly greater eating disorder symptom reductions than controls through 2-year follow-up. Healthy Weight and Project Health participants showed marginally lower eating disorder onset over follow-up than controls (3 and 3% vs 8% respectively). The reduced increases in BMI and future overweight/obesity onset for Project Health relative to both an active matched intervention and a minimal intervention control condition are noteworthy, especially given the short 6-h intervention duration. The reduction in eating disorder symptoms for Healthy Weight and Project Health relative to controls was also encouraging. Results suggest that adding dissonance-induction activities increased weight loss effects. Yet, effects for both were generally small and the eating disorder onset prevention effects were only marginal, potentially because intervention groups included both sexes, which reduced eating disorder incidence and sensitivity.

  9. Beyond the Flipped Classroom: A Highly Interactive Cloud-Classroom (HIC) Embedded into Basic Materials Science Courses

    NASA Astrophysics Data System (ADS)

    Liou, Wei-Kai; Bhagat, Kaushal Kumar; Chang, Chun-Yen

    2016-06-01

    The present study compares the highly interactive cloud-classroom (HIC) system with traditional methods of teaching materials science that utilize crystal structure picture or real crystal structure model, in order to examine its learning effectiveness across three dimensions: knowledge, comprehension and application. The aim of this study was to evaluate the (HIC) system, which incorporates augmented reality, virtual reality and cloud-classroom to teach basic materials science courses. The study followed a pretest-posttest quasi-experimental research design. A total of 92 students (aged 19-20 years), in a second-year undergraduate program, participated in this 18-week-long experiment. The students were divided into an experimental group and a control group. The experimental group (36 males and 10 females) was instructed utilizing the HIC system, while the control group (34 males and 12 females) was led through traditional teaching methods. Pretest, posttest, and delayed posttest scores were evaluated by multivariate analysis of covariance. The results indicated that participants in the experimental group who used the HIC system outperformed the control group, in the both posttest and delayed posttest, across three learning dimensions. Based on these results, the HIC system is recommended to be incorporated in formal materials science learning settings.

  10. An experimental distributed microprocessor implementation with a shared memory communications and control medium

    NASA Technical Reports Server (NTRS)

    Mejzak, R. S.

    1980-01-01

    The distributed processing concept is defined in terms of control primitives, variables, and structures and their use in performing a decomposed discrete Fourier transform (DET) application function. The design assumes interprocessor communications to be anonymous. In this scheme, all processors can access an entire common database by employing control primitives. Access to selected areas within the common database is random, enforced by a hardware lock, and determined by task and subtask pointers. This enables the number of processors to be varied in the configuration without any modifications to the control structure. Decompositional elements of the DFT application function in terms of tasks and subtasks are also described. The experimental hardware configuration consists of IMSAI 8080 chassis which are independent, 8 bit microcomputer units. These chassis are linked together to form a multiple processing system by means of a shared memory facility. This facility consists of hardware which provides a bus structure to enable up to six microcomputers to be interconnected. It provides polling and arbitration logic so that only one processor has access to shared memory at any one time.

  11. Evidence of low dimensional chaos in renal blood flow control in genetic and experimental hypertension

    NASA Astrophysics Data System (ADS)

    Yip, K.-P.; Marsh, D. J.; Holstein-Rathlou, N.-H.

    1995-01-01

    We applied a surrogate data technique to test for nonlinear structure in spontaneous fluctuations of hydrostatic pressure in renal tubules of hypertensive rats. Tubular pressure oscillates at 0.03-0.05 Hz in animals with normal blood pressure, but the fluctuations become irregular with chronic hypertension. Using time series from rats with hypertension we produced surrogate data sets to test whether they represent linearly correlated noise or ‘static’ nonlinear transforms of a linear stochastic process. The correlation dimension and the forecasting error were used as discriminating statistics to compare surrogate with experimental data. The results show that the original experimental time series can be distinguished from both linearly and static nonlinearly correlated noise, indicating that the nonlinear behavior is due to the intrinsic dynamics of the system. Together with other evidence this strongly suggests that a low dimensional chaotic attractor governs renal hemodynamics in hypertension. This appears to be the first demonstration of a transition to chaotic dynamics in an integrated physiological control system occurring in association with a pathological condition.

  12. Experimental study on control performance of tuned liquid column dampers considering different excitation directions

    NASA Astrophysics Data System (ADS)

    Altunişik, Ahmet Can; Yetişken, Ali; Kahya, Volkan

    2018-03-01

    This paper gives experimental tests' results for the control performance of Tuned Liquid Column Dampers (TLCDs) installed on a prototype structure exposed to ground motions with different directions. The prototype structure designed in the laboratory consists of top and bottom plates with four columns. Finite element analyses and ambient vibration tests are first performed to extract the natural frequencies and mode shapes of the structure. Then, the damping ratio of the structure as well as the resonant frequency, head-loss coefficient, damping ratio, and water height-frequency diagram of the designed TLCD are obtained experimentally by the shaking table tests. To investigate the effect of TLCDs on the structural response, the prototype structure-TLCD coupled system is considered later, and its natural frequencies and related mode shapes are obtained numerically. The acceleration and displacement time-histories are obtained by the shaking table tests to evaluate its damping ratio. To consider different excitation directions, the measurements are repeated for the directions between 0° and 90° with 15° increment. It can be concluded from the study that TLCD causes to decrease the resonant frequency of the structure with increasing of the total mass. Damping ratio considerably increases with installing TLCD on the structure. This is more pronounced for the angles of 0°, 15°, 30° and 45°.

  13. Experimental realization of gate controlled topological conducting channels in bilayer graphene

    NASA Astrophysics Data System (ADS)

    Li, J.; McFaul, K. J.; Zern, Z.; Zhu, J.; Wang, K.; Ren, Y. F.; Qiao, Z. H.; Watanabe, K.; Taniguchi, T.

    Manipulating the valley degree of freedom in two-dimensional honeycomb lattices can potentially lead to a new type of electronics called valleytronics. In electrically gapped bilayer graphene, the broken inversion symmetry leads to non-zero and asymmetric Berry curvature Ω in the K and K' valleys of the Brillouin zone. Reversing the sign of Ω at the internal line junction of two oppositely gated bilayer graphene is predicted to yield counter-propagating edge modes, the so-called kink states, with quantized conductance of 4e2 / h in the absence of valley mixing. We have overcome fabrication challenges to implement high-quality hBN encapsulated, dual-split-gates structures necessary to observe the kink states. Here I present experimental evidences of the kink states. In the absence of a magnetic field, the kink states have a mean free path of a few hundred nm. Ballistic conductance of 4e2 / h is achieved in a perpendicular magnetic field. We discuss the potential valley-mixing mechanisms and the role of the magnetic field. Experimental results are supported by numerical studies. We will also discuss ongoing efforts in realizing valley-controlled transmission and guiding of the kink states, which is a significant step towards the development of valleytronics.

  14. Experimental study of an adaptive elastic metamaterial controlled by electric circuits

    NASA Astrophysics Data System (ADS)

    Zhu, R.; Chen, Y. Y.; Barnhart, M. V.; Hu, G. K.; Sun, C. T.; Huang, G. L.

    2016-01-01

    The ability to control elastic wave propagation at a deep subwavelength scale makes locally resonant elastic metamaterials very relevant. A number of abilities have been demonstrated such as frequency filtering, wave guiding, and negative refraction. Unfortunately, few metamaterials develop into practical devices due to their lack of tunability for specific frequencies. With the help of multi-physics numerical modeling, experimental validation of an adaptive elastic metamaterial integrated with shunted piezoelectric patches has been performed in a deep subwavelength scale. The tunable bandgap capacity, as high as 45%, is physically realized by using both hardening and softening shunted circuits. It is also demonstrated that the effective mass density of the metamaterial can be fully tailored by adjusting parameters of the shunted electric circuits. Finally, to illustrate a practical application, transient wave propagation tests of the adaptive metamaterial subjected to impact loads are conducted to validate their tunable wave mitigation abilities in real-time.

  15. A theoretical and experimental study of wood planer noise and its control

    NASA Technical Reports Server (NTRS)

    Stewart, J. S.

    1972-01-01

    A combined analytical and experimental study of wood planer noise is made and the results applied to the development of practical noise control techniques. The dominant mechanisms of sound generation are identified and an analysis is presented which accurately predicts the governing levels of noise emission. Planing operations in which the length of the board is much greater than the width are considered. The dominant source of planer noise is identified as the board being surfaced, which is set into vibration by the impact of cutterhead knives. This is determined from studies made both in the laboratory and in the field concerning the effect of board width on the resulting noise, which indicate a six decibel increase in noise level for each doubling of board width. The theoretical development of a model for board vibration defines the vibrational field set up in the board and serves as a guide for cutterhead redesign.

  16. Experimental Tracking of Limit-Point Bifurcations and Backbone Curves Using Control-Based Continuation

    NASA Astrophysics Data System (ADS)

    Renson, Ludovic; Barton, David A. W.; Neild, Simon A.

    Control-based continuation (CBC) is a means of applying numerical continuation directly to a physical experiment for bifurcation analysis without the use of a mathematical model. CBC enables the detection and tracking of bifurcations directly, without the need for a post-processing stage as is often the case for more traditional experimental approaches. In this paper, we use CBC to directly locate limit-point bifurcations of a periodically forced oscillator and track them as forcing parameters are varied. Backbone curves, which capture the overall frequency-amplitude dependence of the system’s forced response, are also traced out directly. The proposed method is demonstrated on a single-degree-of-freedom mechanical system with a nonlinear stiffness characteristic. Results are presented for two configurations of the nonlinearity — one where it exhibits a hardening stiffness characteristic and one where it exhibits softening-hardening.

  17. Experimental measurement of the plasma conductivity of Z93 and Z93P thermal control paint

    NASA Technical Reports Server (NTRS)

    Hillard, G. Barry

    1993-01-01

    Two samples each of Z93 and Z93P thermal control paint were exposed to a simulated space environment in a plasma chamber. The samples were biased through a series of voltages ranging from -200 volts to +300 volts and electron and ion currents measured. By comparing the currents to those of pure metal samples of the same size and shape, the conductivity of the samples was calculated. Measured conductivity was dependent on the bias potential in all cases. For Z93P, conductivity was approximately constant over much of the bias range and we find a value of 0.5 micro-mhos per square meter for both electron and ion current. For Z93, the dependence on bias was much more pronounced but conductivity can be said to be approximately one order of magnitude larger. In addition to presenting these results, this report documents all of the experimental data as well as the statistical analyses performed.

  18. The Importance of Experimental Design, Quality Assurance, and Control in Plant Metabolomics Experiments.

    PubMed

    Martins, Marina C M; Caldana, Camila; Wolf, Lucia Daniela; de Abreu, Luis Guilherme Furlan

    2018-01-01

    The output of metabolomics relies to a great extent upon the methods and instrumentation to identify, quantify, and access spatial information on as many metabolites as possible. However, the most modern machines and sophisticated tools for data analysis cannot compensate for inappropriate harvesting and/or sample preparation procedures that modify metabolic composition and can lead to erroneous interpretation of results. In addition, plant metabolism has a remarkable degree of complexity, and the number of identified compounds easily surpasses the number of samples in metabolomics analyses, increasing false discovery risk. These aspects pose a large challenge when carrying out plant metabolomics experiments. In this chapter, we address the importance of a proper experimental design taking into consideration preventable complications and unavoidable factors to achieve success in metabolomics analysis. We also focus on quality control and standardized procedures during the metabolomics workflow.

  19. CoDuSe group exercise programme improves balance and reduces falls in people with multiple sclerosis: A multi-centre, randomized, controlled pilot study.

    PubMed

    Carling, Anna; Forsberg, Anette; Gunnarsson, Martin; Nilsagård, Ylva

    2017-09-01

    Imbalance leading to falls is common in people with multiple sclerosis (PwMS). To evaluate the effects of a balance group exercise programme (CoDuSe) on balance and walking in PwMS (Expanded Disability Status Scale, 4.0-7.5). A multi-centre, randomized, controlled single-blinded pilot study with random allocation to early or late start of exercise, with the latter group serving as control group for the physical function measures. In total, 14 supervised 60-minute exercise sessions were delivered over 7 weeks. Pretest-posttest analyses were conducted for self-reported near falls and falls in the group starting late. Primary outcome was Berg Balance Scale (BBS). A total of 51 participants were initially enrolled; three were lost to follow-up. Post-intervention, the exercise group showed statistically significant improvement ( p = 0.015) in BBS and borderline significant improvement in MS Walking Scale ( p = 0.051), both with large effect sizes (3.66; -2.89). No other significant differences were found between groups. In the group starting late, numbers of falls and near falls were statistically significantly reduced after exercise compared to before ( p < 0.001; p < 0.004). This pilot study suggests that the CoDuSe exercise improved balance and reduced perceived walking limitations, compared to no exercise. The intervention reduced falls and near falls frequency.

  20. A numerical and experimental investigation of crystalline silica exposure control during tuck pointing.

    PubMed

    Heitbrink, William; Bennett, James

    2006-07-01

    National Institute for Occupational Safety and Health researchers investigated control measures for the removal of mortar between bricks, using a grinder. This task, "tuck pointing," is associated with crystalline silica exposures many times greater than the permissible exposure limit enforced by the Occupational Safety and Health Administration. Previous studies showed that local exhaust ventilation (LEV) of the grinding wheel through a shroud was often ineffective. Tuck pointing occurs on a scaffold. For practical purposes, this limits the size and power of the LEV system. Thus, the goal of this study was to develop a recommended flow rate for exposure control. Flow induced by the rotating grinding wheel, flow induced by the mortar particle stream, and particle momentum are potential control challenges. Computational fluid dynamic (CFD) simulation of the grinder, supported by some experimental measurements, showed the relative importance of these factors through varying parameters and tracking particles. In a simulation of the shroud and grinding wheel, with the wheel inserted to a cutting depth of 0.750 inch flush into the brick wall, -0.461 cubic feet per meter (0.461 into the exhaust takeoff) was induced by the rotating wheel. The more realistic situation of the wheel in a cut in the wall 1.25 inches deep (forming a trench circumferentially 0.500 inch below the wheel edge) induced an airflow of 8.24 cfm out of the shroud exhaust. Experimental measurements taken for validation were 7.3% lower than the CFD value. The trench effect disappeared when a stream of 10-mu m particles was launched from the grinding wheel edge, as the simulations with and without the trench had nearly identical induced flow rates, 10.8 cfm and 10.9 cfm. We thus interpreted the particle stream as more important than the wheel in inducing flow. This insight was possible because of the power of CFD, compared to intuition and classical boundary layer analysis. In this situation of no forced