Drawing on student knowledge in human anatomy and physiology
NASA Astrophysics Data System (ADS)
Slominski, Tara Nicole
Prior to instruction, students may have developed alternative conceptions about the mechanics behind human physiology. To help students re-shape these ideas into correct reasoning, the faulty characteristics reinforcing the alternative conceptions need to made explicit. This study used student-generated drawings to expose alternative conceptions Human Anatomy and Physiology students had prior to instruction on neuron physiology. Specifically, we investigated how students thought about neuron communication across a synapse (n=355) and how neuron activity can be modified (n=311). When asked to depict basic communication between two neurons, at least 80% of students demonstrated incorrect ideas about synaptic transmission. When targeting spatial and temporal summation, only eleven students (3.5%) were able to accurately depict at least one form of summation. In response to both drawing questions, student drawings revealed multiple alternative conceptions that resulted in a deeper analysis and characterization of the wide variation of student ideas.
ERIC Educational Resources Information Center
Arthurs, Leilani A.; Van Den Broeke, Matthew S.
2016-01-01
The ability to explain scientific phenomena is a key feature of scientific literacy, and engaging students' prior knowledge, especially their alternate conceptions, is an effective strategy for enhancing scientific literacy and developing expertise. The gap in knowledge about the alternate conceptions that novices have about many of Earth's…
Case Study: Formulating Questions That Address Student Misconceptions in a Case Study
ERIC Educational Resources Information Center
Prud'homme-Généreux, Annie
2017-01-01
Misconceptions are sometimes called "alternative conceptions" in acknowledgement of the fact that although these concepts are inaccurate, they are congruent with prior experiences. The idea that misconceptions must be addressed to improve learning is helpful to remember when developing a case study. Students will bring their existing…
Preparation for College General Chemistry: More than Just a Matter of Content Knowledge Acquisition
ERIC Educational Resources Information Center
Cracolice, Mark S.; Busby, Brittany D.
2015-01-01
This study investigates the potential of five factors that may be predictive of success in college general chemistry courses: prior knowledge of common alternate conceptions, intelligence, scientific reasoning ability, proportional reasoning ability, and attitude toward chemistry. We found that both prior knowledge and scientific reasoning ability…
NASA Astrophysics Data System (ADS)
Buaraphan, Khajornsak
2018-01-01
According to the constructivist theory, students' prior conceptions play an important role in their process of knowledge construction and teachers must take those prior conceptions into account when designing learning activities. The interpretive study was conducted to explore grade 8 students' conceptions about force and motion. The research participants were 42 students (21 male, 21 female) from seven Educational Opportunity Expansion Schools in Nakhon Pathom province located at the central region of Thailand. In each school, two low, two medium and two high achievers were selected. The Interview-About-Instance (IAI) technique was used to collect data. All interviews were audio recorded and subsequently transcribed verbatim. The students' conceptions were interpreted into scientific conception (SC), partial scientific conception (PC) and alternative conception (AC). The frequency of each category was counted and calculated for percentage. The results revealed that the students held a variety of prior conceptions about force and motion ranged from SC, PC to AC. Each students, including the high achievers, held mixed conceptions of force and motion. Interesting, the two dominant ACs held by the students were: a) force-implies-motion or motion-implies-force, and b) force coming only from an active agent. The science teachers need to take these ACs into account when designing the learning activities to cope with them. The implications regarding teaching and learning about force and motion are also discussed.
Concepts, Structures, and Goals: Redefining Ill-Definedness
ERIC Educational Resources Information Center
Lynch, Collin; Ashley, Kevin D.; Pinkwart, Niels; Aleven, Vincent
2009-01-01
In this paper we consider prior definitions of the terms "ill-defined domain" and "ill-defined problem". We then present alternate definitions that better support research at the intersection of Artificial Intelligence and Education. In our view both problems and domains are ill-defined when essential concepts, relations, or criteria are un- or…
NASA Astrophysics Data System (ADS)
Osmundson, Ellen
In this study, I explored how children develop and construct their ideas and alternative frameworks in science. Prior work in this area suggested that changes from alternative conceptions to understandings that more closely resemble scientists' models do not occur in a sequential, linear fashion, nor are they easily accomplished. By employing a constructivist framework grounded in dynamic systems to look at learning, alternative conceptions were viewed not as ideas that need to be "confronted and replaced" but rather as pieces of an intricate puzzle of understanding that when combined create a more complete, functional, continuous understanding of science. Specifically, the study examined students' understandings and conceptualizations of light as they studied it formally for eight weeks. Understandings were measured through interviews, student-generated concept maps, classroom interactions and by examining student work samples. The central questions guiding the investigation were: What were children's (ages 9 and 10) conceptions of light? Did children's ideas about light develop during their eight week study of it? If so, what was the nature of these changes? Results from the study indicated that children had numerous ideas about light before their formal study of it based on their experiences with the world. As children studied light, they learned about it in the dynamic, synergistic and interactive processes of adding new ideas, connecting ideas to one another and elaborating understandings to arrive at progressively more complex and scientific understandings of light. Alternative conceptions, served as both productive and non-productive resources for learning. Further, alternative conceptions and prior understandings did not disappear as children developed their ideas about light. Rather "old" ideas were used and reused to provide support the gradual process of cognitive development of children's ideas about light. Findings from this study can be used to provide science instruction that is both rich in content and rich in opportunities to experience the recursive and dynamic nature of science learning.
NASA Astrophysics Data System (ADS)
Wissing, Dennis Robert
The purpose of the this research was to explore undergraduates' conceptual development for oxygen transport and utilization, as a component of a cardiopulmonary physiology and advanced respiratory care course in the allied health program. This exploration focused on the student's development of knowledge and the presence of alternative conceptions, prior to, during, and after completing cardiopulmonary physiology and advanced respiratory care courses. Using the simulation program, SimBioSysTM (Samsel, 1994), student-participants completed a series of laboratory exercises focusing on cardiopulmonary disease states. This study examined data gathered from: (1) a novice group receiving the simulation program prior to instruction, (2) a novice group that experienced the simulation program following course completion in cardiopulmonary physiology, and (3) an intermediate group who experienced the simulation program following completion of formal education in Respiratory Care. This research was based on the theory of Human Constructivism as described by Mintzes, Wandersee, and Novak (1997). Data-gathering techniques were based on theories supported by Novak (1984), Wandersee (1997), and Chi (1997). Data were generated by exams, interviews, verbal analysis (Chi, 1997), and concept mapping. Results suggest that simulation may be an effective instructional method for assessing conceptual development and diagnosing alternative conceptions in undergraduates enrolled in a cardiopulmonary science program. Use of simulation in conjunction with clinical interview and concept mapping may assist in verifying gaps in learning and conceptual knowledge. This study found only limited evidence to support the use of computer simulation prior to lecture to augment learning. However, it was demonstrated that students' prelecture experience with the computer simulation helped the instructor assess what the learner knew so he or she could be taught accordingly. In addition, use of computer simulation after formal instruction was shown to be useful in aiding students identified by the instructor as needing remediation.
ERIC Educational Resources Information Center
Periago, M. Cristina; Bohigas, Xavier
2005-01-01
The aim of this research was to evaluate and analyse second-year industrial engineering and chemical engineering students prior knowledge of conceptual aspects of "circuit theory". Specifically, we focused on the basic concepts of electric potential and current intensity and on the fundamental relationship between them as expressed by Ohm's law.…
Thorn, Christine Johanna; Bissinger, Kerstin; Thorn, Simon; Bogner, Franz Xaver
2016-01-01
Successful learning is the integration of new knowledge into existing schemes, leading to an integrated and correct scientific conception. By contrast, the co-existence of scientific and alternative conceptions may indicate a fragmented knowledge profile. Every learner is unique and thus carries an individual set of preconceptions before classroom engagement due to prior experiences. Hence, instructors and teachers have to consider the heterogeneous knowledge profiles of their class when teaching. However, determinants of fragmented knowledge profiles are not well understood yet, which may hamper a development of adapted teaching schemes. We used a questionnaire-based approach to assess conceptual knowledge of tree assimilation and wood synthesis surveying 885 students of four educational levels: 6th graders, 10th graders, natural science freshmen and other academic studies freshmen. We analysed the influence of learner's characteristics such as educational level, age and sex on the coexistence of scientific and alternative conceptions. Within all subsamples well-known alternative conceptions regarding tree assimilation and wood synthesis coexisted with correct scientific ones. For example, students describe trees to be living on "soil and sunshine", representing scientific knowledge of photosynthesis mingled with an alternative conception of trees eating like animals. Fragmented knowledge profiles occurred in all subsamples, but our models showed that improved education and age foster knowledge integration. Sex had almost no influence on the existing scientific conceptions and evolution of knowledge integration. Consequently, complex biological issues such as tree assimilation and wood synthesis need specific support e.g. through repeated learning units in class- and seminar-rooms in order to help especially young students to handle and overcome common alternative conceptions and appropriately integrate scientific conceptions into their knowledge profile.
Thorn, Simon; Bogner, Franz Xaver
2016-01-01
Successful learning is the integration of new knowledge into existing schemes, leading to an integrated and correct scientific conception. By contrast, the co-existence of scientific and alternative conceptions may indicate a fragmented knowledge profile. Every learner is unique and thus carries an individual set of preconceptions before classroom engagement due to prior experiences. Hence, instructors and teachers have to consider the heterogeneous knowledge profiles of their class when teaching. However, determinants of fragmented knowledge profiles are not well understood yet, which may hamper a development of adapted teaching schemes. We used a questionnaire-based approach to assess conceptual knowledge of tree assimilation and wood synthesis surveying 885 students of four educational levels: 6th graders, 10th graders, natural science freshmen and other academic studies freshmen. We analysed the influence of learner’s characteristics such as educational level, age and sex on the coexistence of scientific and alternative conceptions. Within all subsamples well-known alternative conceptions regarding tree assimilation and wood synthesis coexisted with correct scientific ones. For example, students describe trees to be living on “soil and sunshine”, representing scientific knowledge of photosynthesis mingled with an alternative conception of trees eating like animals. Fragmented knowledge profiles occurred in all subsamples, but our models showed that improved education and age foster knowledge integration. Sex had almost no influence on the existing scientific conceptions and evolution of knowledge integration. Consequently, complex biological issues such as tree assimilation and wood synthesis need specific support e.g. through repeated learning units in class- and seminar-rooms in order to help especially young students to handle and overcome common alternative conceptions and appropriately integrate scientific conceptions into their knowledge profile. PMID:26807974
Two-Year Community: Resolving Misconceptions through Student Reflections
ERIC Educational Resources Information Center
Tawde, Mangala; Boccio, Dona; Kolack, Kevin
2017-01-01
Students arrive in college with significant prior knowledge including misconceptions that hinder their ability to learn new concepts correctly. Misconceptions, or "alternative beliefs," have been widely studied in the physical sciences at higher education institutions; however, there is a paucity of research concerning the community…
NASA Astrophysics Data System (ADS)
de Astudillo, Luisa Rojas; Niaz, Mansoor
1996-06-01
Achievement in science depends on a series of factors that characterize the cognitive abilities of the students and the complex interactions between these factors and the environment that intervenes in the formation of students' background. The objective of this study is to: a) investigate reasoning strategies students use in solving stoichiometric problems; b) explore the relation between these strategies and alternative conceptions, prior knowledge and cognitive variables; and c) interpret the results within an epistemological framework. Results obtained show how stoichiometric relations produce conflicting situations for students, leading to conceptual misunderstanding of concepts, such as mass, atoms and moles. The wide variety of strategies used by students attest to the presence of competing and conflicting frameworks (progressive transitions, cf. Lakatos, 1970), leading to greater conceptual understanding. It is concluded that the methodology developed in this study (based on a series of closely related probing questions, generally requiring no calculations, that elicit student conceptual understanding to varying degrees within an intact classroom context) was influential in improving student performance. This improvement in performance, however, does not necessarily affect students' hard core of beliefs.
New Challenges in Cross Domain Deterrence
2018-06-01
Active and Passive Prior Refutation of Same and Alternative Counterarguments,” Journal of Abnormal Psychology , Vol. 63, No. 2, 1961. Miller, S. E., and...affordability, and maintaining the integrity of U.S. values may, in the end, cause punishment to be the only viable option. 92 For the concept of
NASA Astrophysics Data System (ADS)
Parrott, Annette M.
Problem. Science teachers are charged with preparing students to become scientifically literate individuals. Teachers are given curriculum that specifies the knowledge that students should come away with; however, they are not necessarily aware of the knowledge with which the student arrives or how best to help them navigate between the two knowledge states. Educators must be aware, not only of where their students are conceptually, but how their students move from their prior knowledge and naive theories, to scientifically acceptable theories. The understanding of how students navigate this course has the potential to revolutionize educational practices. Methods. This study explored how five 9th grade biology students reconstructed their cognitive frameworks and navigated conceptual change from prior conception to consensual genetics knowledge. The research questions investigated were: (1) how do students in the process of changing their naive science theories to accepted science theories describe their journey from prior knowledge to current conception, and (2) what are the methods that students utilize to bridge the gap between alternate and consensual science conceptions to effect conceptual change. Qualitative and quantitative methods were employed to gather and analyze the data. In depth, semi-structured interviews formed the primary data for probing the context and details of students' conceptual change experience. Primary interview data was coded by thematic analysis. Results and discussion. This study revealed information about students' perceived roles in learning, the role of articulation in the conceptual change process, and ways in which a community of learners aids conceptual change. It was ascertained that students see their role in learning primarily as repeating information until they could add that information to their knowledge. Students are more likely to consider challenges to their conceptual frameworks and be more motivated to become active participants in constructing their knowledge when they are working collaboratively with peers instead of receiving instruction from their teacher. Articulation was found to be instrumental in aiding learners in identifying their alternate conceptions as well as in revisiting, investigating and reconstructing their conceptual frameworks. Based on the assumptions generated, suggestions were offered to inform pedagogical practice in support of the conceptual change process.
Concept Inventory Development Reveals Common Student Misconceptions about Microbiology †
Briggs, Amy G.; Hughes, Lee E.; Brennan, Robert E.; Buchner, John; Horak, Rachel E. A.; Amburn, D. Sue Katz; McDonald, Ann H.; Primm, Todd P.; Smith, Ann C.; Stevens, Ann M.; Yung, Sunny B.; Paustian, Timothy D.
2017-01-01
Misconceptions, or alternative conceptions, are incorrect understandings that students have incorporated into their prior knowledge. The goal of this study was the identification of misconceptions in microbiology held by undergraduate students upon entry into an introductory, general microbiology course. This work was the first step in developing a microbiology concept inventory based on the American Society for Microbiology’s Recommended Curriculum Guidelines for Undergraduate Microbiology. Responses to true/false (T/F) questions accompanied by written explanations by undergraduate students at a diverse set of institutions were used to reveal misconceptions for fundamental microbiology concepts. These data were analyzed to identify the most difficult core concepts, misalignment between explanations and answer choices, and the most common misconceptions for each core concept. From across the core concepts, nineteen misconception themes found in at least 5% of the coded answers for a given question were identified. The top five misconceptions, with coded responses ranging from 19% to 43% of the explanations, are described, along with suggested classroom interventions. Identification of student misconceptions in microbiology provides a foundation upon which to understand students’ prior knowledge and to design appropriate tools for improving instruction in microbiology. PMID:29854046
The battered woman syndrome: effects of severity and intermittency of abuse.
Dutton, D G; Painter, S
1993-10-01
The concept of a battered woman syndrome was tested by assessing 50 battered women and 25 emotionally abused women who had recently left their relationships. For both groups, essential features of the syndrome were present and were significantly interrelated. Dynamic features of the prior abusive relationship correlated significantly with these sequelae. The concept of intermittency is proposed as an alternative to the cycle of violence theory as main contributor to the syndrome. Predictability of abuse was found to be unrelated to the intermittency measure.
Assessing Elementary Science Methods Students' Understanding about Global Climate Change
ERIC Educational Resources Information Center
Lambert, Julie L.; Lindgren, Joan; Bleicher, Robert
2012-01-01
Global climate change, referred to as climate change in this paper, has become an important planetary issue, and given that K-12 students have numerous alternative conceptions or lack of prior knowledge, it is critical that teachers have an understanding of the fundamental science underlying climate change. Teachers need to understand the natural…
ERIC Educational Resources Information Center
Calik, Muammer; Ayas, Alipasa; Coll, Richard Kevin
2007-01-01
This paper reports on the use of a constructivist-based pedagogy to enhance understanding of some features of solution chemistry. Pre-service science teacher trainees' prior knowledge about the dissolution of salts and sugar in water were elicited by the use of a simple diagnostic tool. The test revealed widespread alternative conceptions. These…
ERIC Educational Resources Information Center
Smith, Gary A.; Bermea, Shannon Belle
2012-01-01
Should instructors assume that students possess conceptual knowledge of plate tectonics when they reach a second college geoscience course? Five cohorts in a historical geology course over 5 y--a total of 149 students--completed an in-class assignment in which they drew sketches of plate boundaries with required annotations. Analysis of the…
ERIC Educational Resources Information Center
Judson, Eugene
2012-01-01
Groups of children at a science museum were pre- and post-assessed with a type of concept map, known as personal meaning maps, to determine what new understandings, if any, they were gaining from participation in a series of structured hands-on activities about bones and the process of bones healing. Close examination was made regarding whether…
Beyond (Models of) Disability?
Beaudry, Jonas-Sébastien
2016-01-01
The strategy of developing an ontology or models of disability as a prior step to settling ethical issues regarding disabilities is highly problematic for two reasons. First, key definitional aspects of disability are normative and cannot helpfully be made value-neutral. Second, if we accept that the contested concept of disability is value-laden, it is far from obvious that there are definitive reasons for choosing one interpretation of the concept over another. I conclude that the concept of disability is better left ethically open-ended or broad enough to encompass the examination of various ethical issues (such as oppression, minority rights, or physical discomfort). Alternatively, the concept of disability could be altogether abandoned in order to focus on specific issues without being hindered by debates about the nature of disability. Only political costs, rather than conceptual considerations internal to the models, could be weighed against such a conclusion. PMID:26892249
Inference of alternative splicing from RNA-Seq data with probabilistic splice graphs
LeGault, Laura H.; Dewey, Colin N.
2013-01-01
Motivation: Alternative splicing and other processes that allow for different transcripts to be derived from the same gene are significant forces in the eukaryotic cell. RNA-Seq is a promising technology for analyzing alternative transcripts, as it does not require prior knowledge of transcript structures or genome sequences. However, analysis of RNA-Seq data in the presence of genes with large numbers of alternative transcripts is currently challenging due to efficiency, identifiability and representation issues. Results: We present RNA-Seq models and associated inference algorithms based on the concept of probabilistic splice graphs, which alleviate these issues. We prove that our models are often identifiable and demonstrate that our inference methods for quantification and differential processing detection are efficient and accurate. Availability: Software implementing our methods is available at http://deweylab.biostat.wisc.edu/psginfer. Contact: cdewey@biostat.wisc.edu Supplementary information: Supplementary data are available at Bioinformatics online. PMID:23846746
Informed consent: not just for procedures anymore.
Feld, Andrew D
2004-06-01
The ethical and legal requirement to obtain informed consent prior to performing a procedure or administering a treatment derives from the concept of personal (patient) autonomy. The competent patient, after receiving appropriate disclosure of the material risks of the procedure or treatment, understanding those risks, the benefits, and the alternative approaches, makes a voluntary and uncoerced informed decision to proceed. This article will present a general overview of the modern concept of informed consent as a process (mutual communication) rather than an event (document signing). The historical evolution of this concept and the legal rulings that have shaped the requirements of informed consent will be cited. The benefits of informed decision making as a communication and risk management tool are presented. This review is intended as general information, and not as legal advice, which should be sought from a health-care attorney.
NASA Astrophysics Data System (ADS)
Wong, Siu Ling; Yung, Benny Hin Wai; Cheng, Man Wai; Lam, Kwok Leung; Hodson, Derek
2006-01-01
This paper reports findings about a curriculum innovation conducted at The University of Hong Kong. A CD-ROM consisting of videos of two lessons by different teachers demonstrating exemplary science teaching was used to elicit conceptions of good science teaching of student-teachers enrolled for the 1-year Postgraduate Diploma in Education at several stages during the programme. It was found that the videos elicited student-teachers’ conceptions and had impact on those conceptions prior to the commencement of formal instruction. It has extended student-teachers’ awareness of alternative teaching methods and approaches not experienced in their own schooling, broadened their awareness of different classroom situations, provided proof of existence of good practices, and prompted them to reflect on their current preconceptions of good science teaching. In several ways, the videos acted as a catalyst in socializing the transition of student-teachers from the role of student to the role of teacher.
Struggling to understand abstract science topics: a Roundhouse diagram-based study
NASA Astrophysics Data System (ADS)
Ward, Robin E.; Wandersee, James H.
2002-06-01
This study explored the effects of Roundhouse diagram construction on a previously low-performing middle school science student's struggles to understand abstract science concepts and principles. It is based on a metacognition-based visual learning model proposed by Wandersee in 1994. Ward and Wandersee introduced the Roundhouse diagram strategy and showed how it could be applied in science education. This article aims at elucidating the process by which Roundhouse diagramming helps learners bootstrap their current understandings to reach the intended meaningful understanding of complex science topics. The main findings of this study are that (a) it is crucial that relevant prior knowledge and dysfunctional alternative conceptions not be ignored during new learning if low-performing science students are to understand science well; (b) as the student's mastery of the Roundhouse diagram construction improved, so did science achievement; and (c) the student's apt choice of concept-related visual icons aided progress toward meaningful understanding of complex science concepts.
Morton, David A.; Pippitt, Karly; Lamb, Sara; Colbert-Getz, Jorie M.
2016-01-01
Problem Effectively solving problems as a team under stressful conditions is central to medical practice; however, because summative examinations in medical education must test individual competence, they are typically solitary assessments. Approach Using two-stage examinations, in which students first answer questions individually (Stage 1) and then discuss them in teams prior to resubmitting their answers (Stage 2), is one method for rectifying this discordance. On the basis of principles of social constructivism, the authors hypothesized that two-stage examinations would lead to better retention of, specifically, items answered incorrectly at Stage 1. In fall 2014, they divided 104 first-year medical students into two groups of 52 students. Groups alternated each week between taking one- and two-stage examinations such that each student completed 6 one-stage and 6 two-stage examinations. The authors reassessed 61 concepts on a final examination and, using the Wilcoxon signed ranked tests, compared performance for all concepts and for just those students initially missed, between Stages 1 and 2. Outcomes Final examination performance on all previously assessed concepts was not significantly different between the one-and two-stage conditions (P = .77); however, performance on only concepts that students initially answered incorrectly on a prior examination improved by 12% for the two-stage condition relative to the one-stage condition (P = .02, r = 0.17). Next Steps Team assessment may be most useful for assessing concepts students find difficult, as opposed to all content. More research is needed to determine whether these results apply to all medical school topics and student cohorts. PMID:27049544
NASA Astrophysics Data System (ADS)
Sheppard, Keith
This study investigated high school students' understanding of acid-base chemistry, prior to and after formal chemistry instruction. Sixteen students enrolled in a regular chemistry course were interviewed three times during the school year; before and after studying the topic of acids and bases and then while conducting a titration using a microcomputer-based laboratory (MBL). Oral, pictorial and graphical data were collected in a variety of acid-base practical tasks. The data were analyzed in two parts; first, common themes, ideas and alternative conceptions that students held were identified; second, profiles of each students were made to determine changes in their conceptions due to instruction. The findings showed that students had considerable difficulty with several areas of acid-base chemistry and did not develop an integrated conceptual understanding of the topic. Students were unable to describe acid-base concepts accurately and revealed a number of alternative conceptions, which remained unchanged by instruction. Specific areas of difficulty included the concepts of pH, neutralization, strength and the theoretical descriptions of acids and bases. Further, most students could not relate the concepts to actual solutions and were unable to describe acid-base phenomena at a sub-microscopic level. Student difficulties stemmed from a lack of understanding of some underlying and fundamental chemistry, such as the nature of chemical change and the particulate nature of matter. A number of factors were identified as contributing to these difficulties, and included the overstuffed nature of introductory chemistry itself, the emphasis in instruction on solving numerical problems and the dominant role played by the textbook. Further, the conceptual density of acid-base chemistry, the confusing nature of acid-base terminology and the lack of agreement about what material should be included in the chemistry curriculum were viewed as problematic. The study calls for a shift in introductory chemistry, from coverage of material to an emphasis on conceptual understanding, and suggests the use of more appropriate teaching strategies, the use of modern technologies, the inclusion of alternative modes of assessment and a re-evaluation of the chemistry introduced into the topic of acids and bases.
Shreffler-Grant, Jean; Nichols, Elizabeth; Weinert, Clarann; Ide, Bette
2016-01-01
This article aims to present and describe a model of complementary and alternative medicine (CAM) health literacy. The model is the conceptual basis for CAM health literacy, which is operationally defined as the information about CAM needed to make informed self-management decisions regarding health. Improving health literacy is a national priority, and widespread use of CAM has added to the complexity of this task. There are no currently available models or measures of health literacy regarding CAM. The authors developed the model using an iterative process of deriving concepts, constructs, and empirical indicators from the literature and the author’s prior work, review and critique by experts, and revision. The model of CAM health literacy can serve as the basis for future research on the use and efficacy of CAM and the constructs and concepts within it can be used to identify points of intervention for research or for clinical practice. It is anticipated that the model will have scientific and clinical application for assessing health literacy in other self care decision-making situations. PMID:23889542
Shreffler-Grant, Jean; Nichols, Elizabeth; Weinert, Clarann; Ide, Bette
2013-01-01
This article aims to present and describe a model of complementary and alternative medicine (CAM) health literacy. The model is the conceptual basis for CAM health literacy, which is operationally defined as the information about CAM needed to make informed self-management decisions regarding health. Improving health literacy is a national priority, and widespread use of CAM has added to the complexity of this task. There are no currently available models or measures of health literacy regarding CAM. The authors developed the model using an iterative process of deriving concepts, constructs, and empirical indicators from the literature and the author's prior work, review and critique by experts, and revision. The model of CAM health literacy can serve as the basis for future research on the use and efficacy of CAM and the constructs and concepts within it can be used to identify points of intervention for research or for clinical practice. It is anticipated that the model will have scientific and clinical application for assessing health literacy in other self care decision-making situations.
Novice and expert teachers' conceptions of learners' prior knowledge
NASA Astrophysics Data System (ADS)
Meyer, Helen
2004-11-01
This study presents comparative case studies of preservice and first-year teachers' and expert teachers' conceptions of the concept of prior knowledge. Kelly's (The Psychology of Personal Construct, New York: W.W. Norton, 1955) theory of personal constructs as discussed by Akerson, Flick, and Lederman (Journal of Research in Science Teaching, 2000, 37, 363-385) in relationship to prior knowledge underpins the study. Six teachers were selected to participate in the case studies based upon their level experience teaching science and their willingness to take part. The comparative case studies of the novice and expert teachers provide insights into (a) how novice and expert teachers understand the concept of prior knowledge and (b) how they use this knowledge to make instructional decisions. Data collection consisted of interviews, classroom observations, and document analysis. Findings suggest that novice teachers hold insufficient conceptions of prior knowledge and its role in instruction to effectively implement constructivist teaching practices. While expert teachers hold a complex conception of prior knowledge and make use of their students' prior knowledge in significant ways during instruction. A second finding was an apparent mismatch between the novice teachers' beliefs about their urban students' life experiences and prior knowledge and the wealth of knowledge the expert teachers found to draw upon.
Structural design principles for self-assembled coordination polygons and polyhedra.
Young, Neil J; Hay, Benjamin P
2013-02-18
Strategies for the design of ligands that combine with metal ions to form high-symmetry coordination assemblies are reviewed. Evaluation of crystal structure evidence reveals that prior design approaches, based on the concept of complementary bonding vector angles, fail to predict the majority of known examples. After explaining the reasons for this failure, it is shown how an alternative approach, de novo structure-based design, provides a practical method that predicts a much wider range of component shapes encoded to direct the formation of such assemblies.
2001-03-01
destruction incident. These exercises identified the need for jurisdictions to formulate response plans that optimize their existing resources by... formulated with state licensing and public health agencies and approved prior to use. Jurisdictions should consider developing guidelines pertaining to...Phenergan), 50mg/ suppository Ea Ringers Lactate, 1000cc Case/6 Saline Solution IV (0.9% 500ml) Case/24 Sodium Bicarbonate (4.2% Injection) (Pkg/10) Pkg/10
A Multifunctional Hot Structure Heatshield Concept for Planetary Entry
NASA Technical Reports Server (NTRS)
Walker, Sandra P.; Daryabeigi, Kamran; Samareh, Jamshid A.; Wagner, Robert; Waters, Allen
2015-01-01
A multifunctional hot structure heatshield concept is being developed to provide technology enhancements with significant benefits compared to the current state-of-the-art heatshield technology. These benefits can potentially enable future planetary missions. The concept is unique in integrating the function of the thermal protection system with the primary load carrying structural component. An advanced carbon-carbon material system has been evaluated for the load carrying structure, which will be utilized on the outer surface of the heatshield, and thus will operate as a hot structure exposed to the severe aerodynamic heating associated with planetary entry. Flexible, highly efficient blanket insulation is sized for use underneath the hot structure to maintain required operational internal temperatures. The approach followed includes developing preliminary designs to demonstrate feasibility of the concept and benefits over a traditional, baseline design. Where prior work focused on a concept for an Earth entry vehicle, the current efforts presented here are focused on developing a generic heatshield model and performing a trade study for a Mars entry application. This trade study includes both structural and thermal evaluation. The results indicate that a hot structure concept is a feasible alternative to traditional heatshields and may offer advantages that can enable future entry missions.
NASA Astrophysics Data System (ADS)
Alao, Solomon
The need to identify factors that contribute to students' understanding of ecological concepts has been widely expressed in recent literature. The purpose of this study was to investigate the relationship between fifth grade students' prior knowledge, learning strategies, interest, and learning goals and their conceptual understanding of ecological science concepts. Subject were 72 students from three fifth grade classrooms located in a metropolitan area of the eastern United States. Students completed the goal commitment, interest, and strategy use questionnaire (GISQ), and a knowledge test designed to assess their prior knowledge and conceptual understanding of ecological science concepts. The learning goals scale assessed intentions to try to learn and understand ecological concepts. The interest scale assessed the feeling and value-related valences that students ascribed to science and ecological science concepts. The strategy use scale assessed the use of two cognitive strategies (monitoring and elaboration). The knowledge test assessed students' understanding of ecological concepts (the relationship between living organisms and their environment). Scores on all measures were examined for gender differences; no significant gender differences were observed. The motivational and cognitive variables contributed to students' understanding of ecological concepts. After accounting for interest, learning goals, and strategy use, prior knowledge accounted for 28% of the total variance in conceptual understanding. After accounting for prior knowledge, interest, learning goals, and strategy use explained 7%, 6%, and 4% of the total variance in conceptual understanding, respectively. More importantly, these variables were interrelated to each other and to conceptual understanding. After controlling for prior knowledge, learning goals, and strategy use, interest did not predict the variance in conceptual understanding. After controlling for prior knowledge, interest, and strategy use, learning goals did not predict the variance in conceptual understanding. And, after controlling for prior knowledge, interest, and learning goals, strategy use did not predict the variance in conceptual understanding. Results of this study indicated that prior knowledge, interest, learning goals, and strategy use should be included in theoretical models design to explain and to predict fifth grade students' understanding of ecological concepts. Results of this study further suggested that curriculum developers and science teachers need to take fifth grade students' prior knowledge of ecological concepts, interest in science and ecological concepts; intentions to learn and understand ecological concepts, and use of cognitive strategies into account when designing instructional contexts to support these students' understanding of ecological concepts.
NASA Astrophysics Data System (ADS)
Meng, Bowen; Xing, Lei; Han, Bin; Koong, Albert; Chang, Daniel; Cheng, Jason; Li, Ruijiang
2013-11-01
Non-coplanar beams are important for treatment of both cranial and noncranial tumors. Treatment verification of such beams with couch rotation/kicks, however, is challenging, particularly for the application of cone beam CT (CBCT). In this situation, only limited and unconventional imaging angles are feasible to avoid collision between the gantry, couch, patient, and on-board imaging system. The purpose of this work is to develop a CBCT verification strategy for patients undergoing non-coplanar radiation therapy. We propose an image reconstruction scheme that integrates a prior image constrained compressed sensing (PICCS) technique with image registration. Planning CT or CBCT acquired at the neutral position is rotated and translated according to the nominal couch rotation/translation to serve as the initial prior image. Here, the nominal couch movement is chosen to have a rotational error of 5° and translational error of 8 mm from the ground truth in one or more axes or directions. The proposed reconstruction scheme alternates between two major steps. First, an image is reconstructed using the PICCS technique implemented with total-variation minimization and simultaneous algebraic reconstruction. Second, the rotational/translational setup errors are corrected and the prior image is updated by applying rigid image registration between the reconstructed image and the previous prior image. The PICCS algorithm and rigid image registration are alternated iteratively until the registration results fall below a predetermined threshold. The proposed reconstruction algorithm is evaluated with an anthropomorphic digital phantom and physical head phantom. The proposed algorithm provides useful volumetric images for patient setup using projections with an angular range as small as 60°. It reduced the translational setup errors from 8 mm to generally <1 mm and the rotational setup errors from 5° to <1°. Compared with the PICCS algorithm alone, the integration of rigid registration significantly improved the reconstructed image quality, with a reduction of mostly 2-3 folds (up to 100) in root mean square image error. The proposed algorithm provides a remedy for solving the problem of non-coplanar CBCT reconstruction from limited angle of projections by combining the PICCS technique and rigid image registration in an iterative framework. In this proof of concept study, non-coplanar beams with couch rotations of 45° can be effectively verified with the CBCT technique.
Alternative conceptions of introductory geoscience students and a method to decrease them
NASA Astrophysics Data System (ADS)
Kortz, Karen Melissa
College students often leave introductory geoscience courses with alternative conceptions, and these alternative conceptions are a barrier to their grasp of geological conceptions. This dissertation clarifies the problem and suggests pedagogical strategies for correcting it. It is an integration of research on students' conceptions of geoscience topics with the application of that knowledge to the development of materials to change these conceptions to be more scientifically accurate. This research identifies and documents alternative conceptions students have in several key geoscience topics and the consequences of these alternative conception in terms of preventing understanding. After documenting the alternative conceptions, I investigate their sources. In addition, I develop ways in which the alternative conceptions can be addressed in classrooms in terms of non-traditional teaching techniques, and I assess the success of these methods. Chapter 1 addresses alternative conceptions in general introductory geoscience topics. I use known student alternative conceptions to develop a series of interactive materials to help reduce students' alternative conceptions. After their development, I assess the efficacy of these materials, and my research indicates that they are successful in helping students better learn the geoscience concepts. Chapter 2 deals with a particularly difficult topic for students---that of phylogenetic systematics. Students have an intuitive way of categorizing organisms, and this categorization is different from the system used by experts within the field. My investigation indicates the conceptual change required of students to fully understand the topic leads to great difficulties with learning. Drawing upon results of the research in Chapter 1, I developed and assessed interactive materials to help students better understand phylogenetic systematics. Using the insight gained from Chapters 1 and 2, Chapters 3 and 4 further examine students' conceptions in an area critical to understanding geology: rocks and their formation. My research indicates that students view rocks as objects independent from the processes that form and change them. In addition, I document students' alternative conceptions of rocks. Using these alternative conceptions, I look more deeply into the underlying factors that cause the difficulties students have with learning rocks, their formation, and their importance to the geosciences.
Evaluation of a value prior to pulping-thermomechanical pulp business concept. Part 2.
Ted Bilek; Carl Houtman; Peter Ince
2011-01-01
Value Prior to Pulping (VPP) is a novel biorefining concept for pulp mills that includes hydrolysis extraction of hemicellulose wood sugars and acetic acid from pulpwood prior to pulping. The concept involves conversion of wood sugars via fermentation to fuel ethanol or other chemicals and the use of remaining solid wood material in the pulping process. This paper...
ERIC Educational Resources Information Center
Abraham, Joel K.; Perez, Kathryn E.; Downey, Nicholas; Herron, Jon C.; Meir, Eli
2012-01-01
Undergraduates commonly harbor alternate conceptions about evolutionary biology; these alternate conceptions often persist, even after intensive instruction, and may influence acceptance of evolution. We interviewed undergraduates to explore their alternate conceptions about macroevolutionary patterns and designed a 2-h lesson plan to present…
NASA Technical Reports Server (NTRS)
Schroeder, J. A.; Merrick, V. K.
1990-01-01
Several control and display concepts were evaluated on a variable-stability helicopter prior to future evaluations on a modified Harrier. The control and display concepts had been developed to enable precise hover maneuvers, station keeping, and vertical landings in simulated zero-visibility conditions and had been evaluated extensively in previous piloted simulations. Flight evaluations early in the program revealed several inadequacies in the display drive laws that were later corrected using an alternative design approach that integrated the control and display characteristics with the desired guidance law. While hooded, three pilots performed landing-pad captures followed by vertical landings with attitude-rate, attitude, and translation-velocity-command control systems. The latter control system incorporated a modified version of state-rate-feedback implicit-model following. Precise landing within 2 ft of the desired touchdown point were achieved.
Priming in implicit memory tasks: prior study causes enhanced discriminability, not only bias.
Zeelenberg, René; Wagenmakers, Eric-Jan M; Raaijmakers, Jeroen G W
2002-03-01
R. Ratcliff and G. McKoon (1995, 1996, 1997; R. Ratcliff, D. Allbritton, & G. McKoon, 1997) have argued that repetition priming effects are solely due to bias. They showed that prior study of the target resulted in a benefit in a later implicit memory task. However, prior study of a stimulus similar to the target resulted in a cost. The present study, using a 2-alternative forced-choice procedure, investigated the effect of prior study in an unbiased condition: Both alternatives were studied prior to their presentation in an implicit memory task. Contrary to a pure bias interpretation of priming, consistent evidence was obtained in 3 implicit memory tasks (word fragment completion, auditory word identification, and picture identification) that performance was better when both alternatives were studied than when neither alternative was studied. These results show that prior study results in enhanced discriminability, not only bias.
What Undergraduates Misunderstand about Stem Cell Research
NASA Astrophysics Data System (ADS)
Halverson, Kristy Lynn; Freyermuth, Sharyn K.; Siegel, Marcelle A.; Clark, Catharine G.
2010-11-01
As biotechnology-related scientific advances, such as stem cell research (SCR), are increasingly permeating the popular media, it has become ever more important to understand students' ideas about this issue. Very few studies have investigated learners' ideas about biotechnology. Our study was designed to understand the types of alternative conceptions students hold concerning SCR. The qualitative research design allowed us to examine college students' understandings about stem cells and SCR. More specifically, we addressed the following questions: How can alternative conceptions about stem cell topics be categorized? What types of alternative conceptions are most common? Participants included 132 students enrolled in a biotechnology course that focused on the scientific background of biotechnology applications relevant to citizens. In this study, we used an inductive approach to develop a taxonomy of alternative ideas about SCR by analyzing student responses to multiple open-ended data sources. We identified five categories of conceptions: alternative conceptions about what, alternative conceptions about how, alternative conceptions about medical potential, terminology confusion, and political and legal alternative conceptions. In order to improve instruction, it is important to understand students' ideas when entering the classroom. Our findings highlight a need to teach how science can be applied to societal issues and improve science literacy and citizenship.
Improved Aerogel Vacuum Thermal Insulation
NASA Technical Reports Server (NTRS)
Ruemmele, Warren P.; Bue, Grant C.
2009-01-01
An improved design concept for aerogel vacuum thermal-insulation panels calls for multiple layers of aerogel sandwiched between layers of aluminized Mylar (or equivalent) poly(ethylene terephthalate), as depicted in the figure. This concept is applicable to both the rigid (brick) form and the flexible (blanket) form of aerogel vacuum thermal-insulation panels. Heretofore, the fabrication of a typical aerogel vacuum insulating panel has involved encapsulation of a single layer of aerogel in poly(ethylene terephthalate) and pumping of gases out of the aerogel-filled volume. A multilayer panel according to the improved design concept is fabricated in basically the same way: Multiple alternating layers of aerogel and aluminized poly(ethylene terephthalate) are assembled, then encapsulated in an outer layer of poly(ethylene terephthalate), and then the volume containing the multilayer structure is evacuated as in the single-layer case. The multilayer concept makes it possible to reduce effective thermal conductivity of a panel below that of a comparable single-layer panel, without adding weight or incurring other performance penalties. Implementation of the multilayer concept is simple and relatively inexpensive, involving only a few additional fabrication steps to assemble the multiple layers prior to evacuation. For a panel of the blanket type, the multilayer concept, affords the additional advantage of reduced stiffness.
Race as a physiosocial phenomenon.
Kendig, Catherine
2011-01-01
This paper offers both a criticism of and a novel alternative perspective on current ontologies that take race to be something that is either static and wholly evident at one's birth or preformed prior to it. In it I survey and critically assess six of the most popular conceptions of race, concluding with an outline of my own suggestion for an alternative account. I suggest that race can be best understood in terms of one's experience of his or her body, one's interactions with other individuals, and one's experiences within particular cultures and societies. This embeddedness of human experience has been left out of most discussions of race which tie race to a set of characteristics (either biologically or sociologically defined). To rectify this omission, I articulate what I call the "physiosocial" view of race. This emphasizes the situatedness of human experience, the reciprocal and dynamic nature of the racial identities of individuals and groups. Approaching racial identity in this way entails a union of two historically uncomfortable partners: biological and sociological conceptions of race. If successful, this philosophical stance may illuminate the process of racial self-ascription as well as provide an explanation for the potential changeability of an individual's racial identity at different times and at different places.
NASA Astrophysics Data System (ADS)
Ben-David Kolikant, Yifat; Genut, Sara
2017-10-01
In line with the growing interest in extending the diversity of CS students, we examined the performance of a unique group of students studying an introductory course in Digital logic: ultraorthodox Jewish men, whose previous education was based mostly on studying Talmud and who lacked a conventional high-school education. We used questions from the Digital Logic Concept Inventory . We compared the results to those of religious Jewish men with a conventional high-school education, and to the results reported in the literature. The ultraorthodox group performed better than the other groups in tasks that concerned number representation. No other statistically significant differences were found. Talk-aloud protocols revealed that the ultraorthodox students utilized a viable conceptual understanding in their performance. We can conclude that students' unique, alternative prior education should not be merely viewed as an obstacle to their academic studies, but also as a potential source for strengths.
ERIC Educational Resources Information Center
Gurlitt, Johannes; Renkl, Alexander
2010-01-01
Two experiments investigated the effects of characteristic features of concept mapping used for prior knowledge activation. Characteristic demands of concept mapping include connecting lines representing the relationships between concepts and labeling these lines, specifying the type of the semantic relationships. In the first experiment,…
Preservice Teachers' Alternative Conceptions in Elementary Science Concepts
ERIC Educational Resources Information Center
Koc, Isil; Yager, Robert E.
2016-01-01
This study was conducted to investigate the extent to which preservice teachers held alternative conceptions in elementary science concepts. Eighty-six preservice elementary teachers participated in this study. Twelve preservice elementary teachers participated in follow-up interviews. Data were collected through the use of Alternative Conceptions…
ERIC Educational Resources Information Center
Lin, Shih-Yin; Singh, Chandralekha
2015-01-01
It is well known that introductory physics students often have alternative conceptions that are inconsistent with established physical principles and concepts. Invoking alternative conceptions in the quantitative problem-solving process can derail the entire process. In order to help students solve quantitative problems involving strong…
ERIC Educational Resources Information Center
Dega, Bekele Gashe; Kriek, Jeanne; Mogese, Temesgen Fereja
2013-01-01
The purpose of this study was to categorize 35 Ethiopian undergraduate physics students' alternative conceptions in the concepts of electric potential and energy. A descriptive qualitative research design was used to categorize the students' alternative conceptions. Four independently homogeneous ability focus groups were formed to elicit the…
Menshikov, Ivan S; Shklover, Alexsandr V; Babkina, Tatiana S; Myagkov, Mikhail G
2017-01-01
In this research, the social behavior of the participants in a Prisoner's Dilemma laboratory game is explained on the basis of the quantal response equilibrium concept and the representation of the game in Markov strategies. In previous research, we demonstrated that social interaction during the experiment has a positive influence on cooperation, trust, and gratefulness. This research shows that the quantal response equilibrium concept agrees only with the results of experiments on cooperation in Prisoner's Dilemma prior to social interaction. However, quantal response equilibrium does not explain of participants' behavior after social interaction. As an alternative theoretical approach, an examination was conducted of iterated Prisoner's Dilemma game in Markov strategies. We built a totally mixed Nash equilibrium in this game; the equilibrium agrees with the results of the experiments both before and after social interaction.
Myagkov, Mikhail G.
2017-01-01
In this research, the social behavior of the participants in a Prisoner's Dilemma laboratory game is explained on the basis of the quantal response equilibrium concept and the representation of the game in Markov strategies. In previous research, we demonstrated that social interaction during the experiment has a positive influence on cooperation, trust, and gratefulness. This research shows that the quantal response equilibrium concept agrees only with the results of experiments on cooperation in Prisoner’s Dilemma prior to social interaction. However, quantal response equilibrium does not explain of participants’ behavior after social interaction. As an alternative theoretical approach, an examination was conducted of iterated Prisoner's Dilemma game in Markov strategies. We built a totally mixed Nash equilibrium in this game; the equilibrium agrees with the results of the experiments both before and after social interaction. PMID:29190280
Core concepts of spatial prioritisation in systematic conservation planning.
Kukkala, Aija S; Moilanen, Atte
2013-05-01
Systematic conservation planning (SCP) is a field of conservation biology concerned with delivering on-the-ground actions that achieve conservation goals. It describes a set of operational models that cover both design and implementation of conservation, with a strong focus on mobilising the collective action typically required to implement conservation. SCP, as it was originally described, was composed of six different stages: collection of data, identification of conservation goals, evaluation of the existing protected area network, design of expansions, implementation of conservation action, and long-term maintenance of biodiversity in the network. Since then, the operational model has been expanded into several different variants. Conservation actions applied inside SCP include establishment and expansion of reserve networks and allocation of habitat restoration and management. Within the broader context of SCP, there is a fundamental biogeographic-economic analysis frequently called spatial conservation prioritisation or conservation assessment, which is used for identifying where important areas for biodiversity are and how conservation goals might be achieved efficiently. Here, we review the usage and meaning of the 12 biogeographic-economic core concepts of SCP: adequacy, complementarity, comprehensiveness, effectiveness, efficiency, flexibility, irreplaceability, replacement cost, representation, representativeness, threat, and vulnerability. Some of the concepts have clear definitions whereas others may have alternative and possibly conflicting definitions. With a comprehensive literature review literature, we elucidate the historical backgrounds of these concepts, the first definitions and usages, alternative later definitions, key applications, and prior reviews. This review reduces linguistic uncertainty in the application of SCP. Since SCP is a global activity with a multitude of different stakeholders involved, it is vital that those involved can speak the same language. Through these concepts, this review serves as a source of information about the historical development of SCP. It provides a comprehensive review for anyone wishing to understand the key concepts of spatial prioritisation within SCP. © 2012 The Authors. Biological Reviews © 2012 Cambridge Philosophical Society.
Core concepts of spatial prioritisation in systematic conservation planning
Kukkala, Aija S; Moilanen, Atte
2013-01-01
Systematic conservation planning (SCP) is a field of conservation biology concerned with delivering on-the-ground actions that achieve conservation goals. It describes a set of operational models that cover both design and implementation of conservation, with a strong focus on mobilising the collective action typically required to implement conservation. SCP, as it was originally described, was composed of six different stages: collection of data, identification of conservation goals, evaluation of the existing protected area network, design of expansions, implementation of conservation action, and long-term maintenance of biodiversity in the network. Since then, the operational model has been expanded into several different variants. Conservation actions applied inside SCP include establishment and expansion of reserve networks and allocation of habitat restoration and management. Within the broader context of SCP, there is a fundamental biogeographic-economic analysis frequently called spatial conservation prioritisation or conservation assessment, which is used for identifying where important areas for biodiversity are and how conservation goals might be achieved efficiently. Here, we review the usage and meaning of the 12 biogeographic-economic core concepts of SCP: adequacy, complementarity, comprehensiveness, effectiveness, efficiency, flexibility, irreplaceability, replacement cost, representation, representativeness, threat, and vulnerability. Some of the concepts have clear definitions whereas others may have alternative and possibly conflicting definitions. With a comprehensive literature review literature, we elucidate the historical backgrounds of these concepts, the first definitions and usages, alternative later definitions, key applications, and prior reviews. This review reduces linguistic uncertainty in the application of SCP. Since SCP is a global activity with a multitude of different stakeholders involved, it is vital that those involved can speak the same language. Through these concepts, this review serves as a source of information about the historical development of SCP. It provides a comprehensive review for anyone wishing to understand the key concepts of spatial prioritisation within SCP. PMID:23279291
ERIC Educational Resources Information Center
Ozmen, Haluk
2008-01-01
This study aims to determine prospective science student teachers' alternative conceptions of the chemical equilibrium concept. A 13-item pencil and paper, two-tier multiple choice diagnostic instrument, the Test to Identify Students' Alternative Conceptions (TISAC), was developed and administered to 90 second-semester science student teachers…
Method for Analyzing Students' Utilization of Prior Physics Learning in New Contexts
ERIC Educational Resources Information Center
McBride, Dyan L.; Zollman, Dean; Rebello, N. Sanjay
2010-01-01
In prior research, the classification of concepts into three types--descriptive, hypothetical and theoretical--has allowed for the association of students' use of different concept types with their level of understanding. Previous studies have also examined the ways in which students link concepts to determine whether students have a meaningful…
1983-03-01
THIS STUDY EXAMINES THE DIFFERENCE BETWEEN THE SELECTIVE SERVICE SYSTEM’S (SSS) CONCEPT OF ALTERNATIVE SERVICE AND THOSE ESPOUSED BY THE MENNONITE CHURCH...System’s (SSS) concept of Alternative Service and those espoused by the Mnnonite Church, the most articulate opponent of current administration planning...adminisrat-ion of an alternative service program. on January 22, the SSS puiblished its proposed concept for alternative service in the Federal Register and
NASA Astrophysics Data System (ADS)
Yalçınkaya, Eylem; Taştan-Kırık, Özgecan; Boz, Yezdan; Yıldıran, Demet
2012-07-01
Background: Case-based learning (CBL) is simply teaching the concept to the students based on the cases. CBL involves a case, which is a scenario based on daily life, and study questions related to the case, which allows students to discuss their ideas. Chemical kinetics is one of the most difficult concepts for students in chemistry. Students have generally low levels of conceptual understanding and many alternative conceptions regarding it. Purpose: This study aimed to explore the effect of CBL on dealing with students' alternative conceptions about chemical kinetics. Sample: The sample consists of 53 high school students from one public high school in Turkey. Design and methods : Nonequivalent pre-test and post-test control group design was used. Reaction Rate Concept Test and semi-structured interviews were used for data collection. Convenience sampling technique was followed. For data analysis, the independent samples t-test and ANOVA was performed. Results : Both concept test and interview results showed that students instructed with cases had better understanding of core concepts of chemical kinetics and had less alternative conceptions related to the subject matter compared to the control group students, despite the fact that it was impossible to challenge all the alternative conceptions in the experimental group. Conclusions: CBL is an effective teaching method for challenging students' alternative conceptions in the context of chemical kinetics. Since using cases in small groups and whole class discussions has been found to be an effective way to cope with the alternative conceptions, it can be applied to other subjects and grade levels in high schools with a higher sample size. Furthermore, the effect of this method on academic achievement, motivation and critical thinking skills are other variables that can be investigated for future studies in the subject area of chemistry.
ERIC Educational Resources Information Center
Popova-Gonci, Viktoria; Lamb, Monica C.
2012-01-01
Prior learning assessment (PLA) students enter academia with different types of concepts--some of them have been formally accepted and labeled by academia and others are informally formulated by students via independent and/or experiential learning. The critical goal of PLA practices is to assess an intricate combination of prior learning…
NASA Astrophysics Data System (ADS)
Koc, Isil
The present study was conducted to investigate the extent to which preservice elementary teachers held alternative conceptions in fundamental elementary science concepts from earth/space science, life science, and physical science along with their self-efficacy beliefs about science teaching and to determine the relationship between these two issues. Eighty-six preservice elementary education majors enrolled in the four sections of the course titled "07E:162 Methods Elementary School Science" offered in the Science Education Center, College of Education, the University of Iowa during the 2005-2006 academic year participated in this study. Twelve preservice elementary teachers participated in follow-up interviews. Data were collected through the use of Alternative Conceptions in Science Instrument constructed by Schoon and Boone (1998), Science Teaching Efficacy Belief Instrument (STEBI-B) constructed by Enochs and Riggs (1990), a participant information form, and through utilization of interviews. The results from the alternative conception instrument indicated that the majority of preservice elementary teachers held a number of alternative conceptions with most being in the physical sciences followed by earth/space, and then life science. Various sources of alternative conceptions emerged during the interview sessions. Participants mainly cited science teachers, science textbooks, and previous science experiences as sources of their alternative conceptions. On the other hand, the analysis of the self-efficacy instrument and follow-up interviews revealed generally positive self-efficacy beliefs. Findings from the study also confirmed that science courses completed in high school and college do not seem to have influenced participants' number and types of alternative conceptions regarding earth/space science, life science, and physical science and self-efficacy beliefs about science teaching. The results also indicate that participants with the lowest number of alternative conceptions regarding earth/space science, physical science, and life science have a relatively high personal science teaching efficacy. Overall, the results of the study regarding self-efficacy beliefs propose that consideration be given to identification and modification of preservice elementary teachers' science alternative conceptions if they are expected to teach science effectively.
Risk-Informed Decision Making: Application to Technology Development Alternative Selection
NASA Technical Reports Server (NTRS)
Dezfuli, Homayoon; Maggio, Gaspare; Everett, Christopher
2010-01-01
NASA NPR 8000.4A, Agency Risk Management Procedural Requirements, defines risk management in terms of two complementary processes: Risk-informed Decision Making (RIDM) and Continuous Risk Management (CRM). The RIDM process is used to inform decision making by emphasizing proper use of risk analysis to make decisions that impact all mission execution domains (e.g., safety, technical, cost, and schedule) for program/projects and mission support organizations. The RIDM process supports the selection of an alternative prior to program commitment. The CRM process is used to manage risk associated with the implementation of the selected alternative. The two processes work together to foster proactive risk management at NASA. The Office of Safety and Mission Assurance at NASA Headquarters has developed a technical handbook to provide guidance for implementing the RIDM process in the context of NASA risk management and systems engineering. This paper summarizes the key concepts and procedures of the RIDM process as presented in the handbook, and also illustrates how the RIDM process can be applied to the selection of technology investments as NASA's new technology development programs are initiated.
NASA Astrophysics Data System (ADS)
Rutherford, Lori B.
The purpose of this study was to (1) identify alternative conceptions concerning astronomy in groups of formal and informal educators, (2) discover the origins of some of these conceptions and (3) explore how practicing teachers planned to address the need for conceptual change in their students. In response to the first question, a number of alternative conceptions were identified in formal educators, with more for teachers of prekindergarten through third grade than fourth through twelfth grade teachers, and very few alternative conceptions in the informal educators group. In regards to the second research question, a number of origins were indicated: logic, books, elementary school, high school, astronomy classes, self-study and observation. In response to the third question, various practicing teachers used computer programs and modeling in order to address some of the alternative conceptions they noticed in their students. These findings were supported by the literature and theoretical frameworks on which the study was based. The study addressed gaps in the literature concerning alternative conceptions and how they related to Ohio's Academic Content Standards along with nineteen other states. This study also addressed the need for a closer examination of informal educators and how they compare to formal educators in terms of having alternative conceptions. And finally, implications and recommendations were made for practicing educators, materials for practicing educators, teacher education, informal and formal education partnerships, standards modification, research methodology and areas of future research.
ERIC Educational Resources Information Center
Anderson, Shawn M.; Velez, Jonathan J.; Thompson, Gregory W.
2014-01-01
This study examined the K-12 teachers' conceptions of the agriculture industry prior to enrolling in an agricultural literacy program and how their conceptions changed throughout the program. The study used qualitative methods to analyze the data collected from entrance questionnaires, interviews, and reflective journals. Trustworthiness was…
NASA Astrophysics Data System (ADS)
Mangione, Katherine Anna
This study was to determine reliability and validity for a two-tiered, multiple- choice instrument designed to identify alternative conceptions in earth science. Additionally, this study sought to identify alternative conceptions in earth science held by preservice teachers, to investigate relationships between self-reported confidence scores and understanding of earth science concepts, and to describe relationships between content knowledge and alternative conceptions and planning instruction in the science classroom. Eighty-seven preservice teachers enrolled in the MAT program participated in this study. Sixty-eight participants were female, twelve were male, and seven chose not to answer. Forty-seven participants were in the elementary certification program, five were in the middle school certification program, and twenty-nine were pursuing secondary certification. Results indicate that the two-tiered, multiple-choice format can be a reliable and valid method for identifying alternative conceptions. Preservice teachers in all certification areas who participated in this study may possess common alternative conceptions previously identified in the literature. Alternative conceptions included: all rivers flow north to south, the shadow of the Earth covers the Moon causing lunar phases, the Sun is always directly overhead at noon, weather can be predicted by animal coverings, and seasons are caused by the Earth's proximity to the Sun. Statistical analyses indicated differences, however not all of them significant, among all subgroups according to gender and certification area. Generally males outperformed females and preservice teachers pursuing middle school certification had higher scores on the questionnaire followed by those obtaining secondary certification. Elementary preservice teachers scored the lowest. Additionally, self-reported scores of confidence in one's answers and understanding of the earth science concept in question were analyzed. There was a slight positive correlation between overall score and both confidence and understanding. Responses on the questionnaire were investigated with respect to pedagogical choices. Evidence suggests that content knowledge and having alternative conceptions or science fragments may impact a teacher's pedagogical choices. Through careful development of instruments like ACES-Q II-R and other two- tiered, multiple-choice instruments, educators and researchers car not only identify possible alternative conceptions, they can raise an awareness of alternative conceptions held by children and adults.
Alternative Conceptions: Turning Adversity into Advantage
NASA Astrophysics Data System (ADS)
Ferreira, Annalize; Lemmer, Miriam; Gunstone, Richard
2017-08-01
While a vast body of research has identified difficulties in students' understanding about forces and acceleration and their related alternative conceptions, far less research suggests ways to use students' alternative conceptions to enhance conceptual understanding of a specific fundamental concept. This study focused on distinguishing between students' conceptual understanding of the Newtonian concept of gravitational acceleration being the same for all objects and students' alternative conception that heavy objects fall faster. A multiple choice questionnaire was distributed to first year physics students for three consecutive years at a university in South Africa. The results indicate that changing the direction of motion and the physics quantity asked in paired questions revealed practically significant inconsistencies in students' reasoning and conceptions. This research contributes to the body of knowledge in proposing how the alternative conception of mass-related gravitational acceleration can be used in instruction to enhance conceptual understanding of the force-mass-acceleration relationship. Understanding of this relationship not only promotes conceptual understanding of the basic Newtonian concepts of the laws of motion which forms the critical foundation on which more advanced physics courses are built, but also contributes towards students' perception of physics as a set of coherent ideas applicable in all contexts.
Being a Mentor: Novice Teachers' Mentors' Conceptions of Mentoring Prior to Training
ERIC Educational Resources Information Center
Schatz-Oppenheimer, Orna
2017-01-01
This study deals with novice teachers' mentors' conceptions of mentoring prior to their mentoring training. In Israel, all novice teachers have to be supported and assessed by a mentor during their first year of teaching. The aim of this study was to elicit from prospective mentors their own conception of professional mentoring, as a basis for…
ERIC Educational Resources Information Center
Warfa, Abdi-Rizak M.; Odowa, N.
2015-01-01
Creative exercises (CEs), a specific form of open-ended assessment tools, have been shown to promote students' linking of prior and newly learned concepts within a course. In this study, we examined how often students in an upper-division undergraduate biochemistry course linked prior chemical concepts to biochemical ones in response to CE…
23 CFR 636.209 - What items must be included in a phase-two solicitation?
Code of Federal Regulations, 2010 CFR
2010-04-01
.... (b) At your discretion, you may allow proposers to submit alternate technical concepts in their proposals as long as these alternate concepts do not conflict with criteria agreed upon in the environmental decision making process. Alternate technical concept proposals may supplement, but not substitute for base...
Alternative Conceptions about Micro-Organisms Are Influenced by Experiences with Disease in Children
ERIC Educational Resources Information Center
Prokop, Pavol; Fancovicová, Jana; Krajcovicová, Adriána
2016-01-01
Children's ideas concerning natural phenomena often differ from those of scientists, and these ideas are termed as alternative conceptions. The prevalence of alternative conceptions is highest among young children who possess less experience with the natural world as compared with adults. Children's ideas about micro-organisms are of special…
ERIC Educational Resources Information Center
Kurt, Hakan; Ekici, Gulay; Aktas, Murat; Aksu, Ozlem
2013-01-01
In researches, the subject of respiration has been determined to be among subjects about whom participants from all educational levels struggle to form their cognitive structures and have many alternative conceptions. This research was carried out in order to determine biology student teachers' cognitive structures and alternative conceptions…
Chicano Alternative Education.
ERIC Educational Resources Information Center
Galicia, H. Homero; Almaguer, Clementina
Alternative schooling is challenging some basic notions of curriculum, operation, and structure of traditional schools; it is not challenging the basic concept of schooling. Chicano alternative education, an elusive concept, lacks a precise definition. Chicano alternative schools reflect a vast diversity in structure, focus, and goals. The Chicano…
Cultural factors in the origin and remediation of alternative conceptions in physics
NASA Astrophysics Data System (ADS)
Thijs, Gerard D.; van den Berg, Ed
1995-10-01
Over a wide range of subject areas students exhibit persistent conceptions contrary to the prevailing scientific concepts. The same alternative conceptions in physics are reported to exist across many countries, within a variety of cultural and environmental contexts. Also, many alternative conceptions show striking similarities with difficulties encountered in the historical development of physics. What is the reason for these similarities? Is intuitive science learned or triggered? And, if similar brain structures are responsible for common-sense theories, in what way then are cultural factors still important in the teaching-learning process? The influence of cultural factors will be discussed on the basis of literature available on this topic. Data collected by the authors in the Netherlands, Indonesia and countries in Africa are also taken into consideration. A distinction is proposed between alternative conceptions some of which may be universal and some dependent on culture. The same distinction is made regarding ways of reasoning and epistemology. It is suggested that the effectiveness of methods for the remediation of alternative conceptions is strongly influenced by cultural aspects of the teaching-learning process.
Thai Grade 11 students' alternative conceptions for acid-base chemistry
NASA Astrophysics Data System (ADS)
Artdej, Romklao; Ratanaroutai, Thasaneeya; Coll, Richard Kevin; Thongpanchang, Tienthong
2010-07-01
This study involved the development of a two-tier diagnostic instrument to assess Thai high school students' understanding of acid-base chemistry. The acid-base diagnostic test (ABDT) comprising 18 items was administered to 55 Grade 11 students in a science and mathematics programme during the second semester of the 2008 academic year. Analysis of students' responses from this study followed the methodology outlined by Çalik and Ayas. The research findings suggest that the ABDT, the multiple choice diagnostic instrument, enables researchers and teachers to classify students' understanding at different levels. Most students exhibited alternative conceptions for several concepts: acid-base theory, dissociation of strong acids or bases, and dissociation of weak acids/bases. Interestingly, one of the concepts that students appeared to find most difficult, and for which they exhibited the most alternative conceptions, was acid-base theory. Some alternative conceptions revealed in this study differ from earlier reports, such as the concept of electrolyte and non-electrolyte solutions as well as the concentration changes of H3O+and OH- in water. These research findings present valuable information for facilitating better understanding of acid-base chemistry by providing insight into the preventable and correctable alternative conceptions exhibited by students.
Taiwanese Students' Alternative Conceptions of Animal Biodiversity
ERIC Educational Resources Information Center
Yen, Chiung-Fen; Yao, Tsung-Wei; Mintzes, Joel J.
2007-01-01
This study explored and documented Taiwanese students' alternative conceptions of animal classification. We examined the understanding of the "animal", "vertebrate" and "invertebrate", "fish", "amphibian", "reptile", "bird", and "mammal" concepts among elementary,…
ERIC Educational Resources Information Center
Mangione, Katherine Anna
2010-01-01
This study was to determine reliability and validity for a two-tiered, multiple- choice instrument designed to identify alternative conceptions in earth science. Additionally, this study sought to identify alternative conceptions in earth science held by preservice teachers, to investigate relationships between self-reported confidence scores and…
Transitions of Care Model Inclusive of Unplanned Care Improves the Patient Experience
Cox, Jon; Teague, Stephanie; Beck, Eric
2016-01-01
A major emphasis in health care is creating an experience whereby patients receive the right care at the right time from the right provider in the right setting at the right cost. Over the past several decades, there has been considerable effort in the area of medical management, with prior authorization, gatekeeper utilization management regimens, and other techniques designed to guide patients and caregivers into desired treatment pathways. Alternatively, the concept of demand management may be employed to achieve these desired outcomes by giving patients meaningful, expanded choices beyond traditional acute-care settings. The implementation of a novel, patient-centered, unplanned care delivery model is described along with illustrative case studies. PMID:28725828
Examing nursing students' understanding of the cardiovascular system in a BSN program
NASA Astrophysics Data System (ADS)
Stuart, Parker Emerson
This study investigated the alignment of important cardiovascular system (CVS) concepts identified by expert nurses with nursing student's knowledge. Specifically, it focused on the prevalence of nursing students' alternative conceptions for these important concepts as a potential reason for a theory-practice gap in nursing (Corlett, 2000; Jordan, 1994). This is the first study to target nursing student alternative conceptions exclusively whereas other studies focused on diverse groups of undergraduates' CVS knowledge (Michael et al., 2002). The study was divided into two phases and used a case study approach with each phase of the study representing a single case. The first phase of the study sought to understand what CVS concepts expert nurses deemed relevant to their daily practice and how these experts used these concepts. The second phase identified nursing student alternative conceptions through the use of open-ended scenarios based on the results of phase I. For the first phase of the study involved four CVS expert nurses practicing in emergency rooms and cardiac intensive care units at two local hospitals. Interviews were used to elicit important CVS concepts. The expert nurses identified five broad concepts as important to their practice. These concepts were a) cardiovascular anatomical concepts; b) cardiovascular physiological concepts; c) homeostasis and diseases of the CVS; d) the interdependence and interaction of the CVS with other organ systems and e) the intersection of the CVS and technology in patient diagnosis and treatment. These finding reinforce concepts already being taught to nursing students but also suggest that instruction should focus more on how the CVS interacts with other organ systems and how technology and the CVS interact. The presence of alternative conceptions in the nursing students was examined through the use of open-ended questions. A total of 17 students fully completed the scenario questions. Results indicate that this group of nursing students hold some CVS alternative conceptions. Overall, the alternative conceptions can be grouped into four categories: a) CVS anatomy, b) blood flow and pressure, c) anthropomorphic views and d) miscellaneous alternative conceptions. These findings suggest there is indeed a misalignment between expert nurses' and nursing students' knowledge of the CVS with this misalignment potentially contributing to the theory-practice gap.
A reassessment of state-level covariates of militia groups.
Freilich, Joshua D; Pridemore, William Alex
2005-01-01
This study investigated state-level variation in the number of right-wing militia groups. We built on prior quantitative examinations by more carefully operationalizing theoretical concepts and testing alternative hypotheses offered to account for the etiology of social movements generally and of militias specifically. Using negative binomial regression, we found that, consistent with previous research, states with higher levels of farm job loss had more militia groups. However, in contrast to prior studies, we did not find gun culture, hospitable political climate, female empowerment, or general economic deprivation to be associated with the number of militia groups. We also found no relationship between the number of militia groups and levels of fundamentalist religious culture and minority empowerment. Our study was the first to test the effects of social disorganization on the number of militias in a state, and we found the two to be positively and significantly associated. We situate our results in the theoretical and empirical literature and outline two challenges for future research. First, scholars must operationalize variables carefully since different measures of the same theoretical concept may result in diverging conclusions. Second, since one major factor (i.e., social disorganization) found in this study to be associated with the number of militia groups in a state was examined here for the first time, it is important for researchers to continue to investigate new hypotheses.
Evaluation of Students' Energy Conception in Environmental Science
ERIC Educational Resources Information Center
Park, Mihwa; Johnson, Joseph A.
2016-01-01
While significant research has been conducted on students' conceptions of energy, alternative conceptions of energy have not been actively explored in the area of environmental science. The purpose of this study is to examine students' alternative conceptions in the environmental science discipline through the analysis of responses of first year…
Conceptual change strategies in teaching genetics
NASA Astrophysics Data System (ADS)
Batzli, Laura Elizabeth
The purpose of this study was to evaluate the effectiveness of utilizing conceptual change strategies when teaching high school genetics. The study examined the effects of structuring instruction to provide students with cognitive situations which promote conceptual change, specifically instruction was structured to elicit students' prior knowledge. The goal of the study was that the students would not only be able to solve genetics problems and define basic terminology but they would also have constructed more scientific schemas of the actual processes involved in inheritance. This study is based on the constructivist theory of learning and conceptual change research which suggest that students are actively involved in the process of relating new information to prior knowledge as they construct new knowledge. Two sections of biology II classes received inquiry based instruction and participated in structured cooperative learning groups. However, the unique difference in the treatment group's instruction was the use of structured thought time and the resulting social interaction between the students. The treatment group students' instructional design allowed students to socially construct their cognitive knowledge after elicitation of their prior knowledge. In contrast, the instructional design for the control group students allowed them to socially construct their cognitive knowledge of genetics without the individually structured thought time. The results indicated that the conceptual change strategies with individually structured thought time improved the students' scientific mastery of genetics concepts and they maintained fewer post instructional alternative conceptions. Although all students gained the ability to correctly solve genetics problems, the treatment group students were able to explain the processes involved in terms of meiosis. The treatment group students were also able to better apply their knowledge to novel genetic situations. The implications for genetics instruction from these results were discussed.
Couturier, Jean‐Luc; Kokossis, Antonis; Dubois, Jean‐Luc
2016-01-01
Abstract Biorefineries offer a promising alternative to fossil‐based processing industries and have undergone rapid development in recent years. Limited financial resources and stringent company budgets necessitate quick capital estimation of pioneering biorefinery projects at the early stages of their conception to screen process alternatives, decide on project viability, and allocate resources to the most promising cases. Biorefineries are capital‐intensive projects that involve state‐of‐the‐art technologies for which there is no prior experience or sufficient historical data. This work reviews existing rapid cost estimation practices, which can be used by researchers with no previous cost estimating experience. It also comprises a comparative study of six cost methods on three well‐documented biorefinery processes to evaluate their accuracy and precision. The results illustrate discrepancies among the methods because their extrapolation on biorefinery data often violates inherent assumptions. This study recommends the most appropriate rapid cost methods and urges the development of an improved early‐stage capital cost estimation tool suitable for biorefinery processes. PMID:27484398
Flight Crew Responses to the Interval Management Alternative Clearances (IMAC) Experiment
NASA Technical Reports Server (NTRS)
Baxley, Brian T.; Wilson, Sara R.; Swieringa, Kurt A.; Roper, Roy D.
2016-01-01
Interval Management Alternative Clearances (IMAC) was a human-in-the-loop simulation experiment conducted to explore the efficacy and acceptability of three IM operations: CAPTURE, CROSS, and MAINTAIN. Two weeks of data collection were conducted, with each week using twelve subject pilots and four subject controllers flying ten high-density arrival scenarios into the Denver International Airport. Overall, both the IM operations and procedures were rated very favorably by the flight crew in terms of acceptability, workload, and pilot head down time. However, several critical issues were identified requiring resolution prior to real-world implementation, including the high frequency of IM speed commands, IM speed commands requiring changes to aircraft configuration, and ambiguous IM cockpit displays that did not trigger the intended pilot reaction. The results from this experiment will be used to prepare for a flight test in 2017, and to support the development of an advanced IM concept of operations by the FAA (Federal Aviation Agency) and aviation industry.
Problem-based learning in teaching chemistry: enthalpy changes in systems
NASA Astrophysics Data System (ADS)
Ayyildiz, Yildizay; Tarhan, Leman
2018-01-01
Problem-based learning (PBL) as a teaching strategy has recently become quite widespread in especially chemistry classes. Research has found that students, from elementary through college, have many alternative conceptions regarding enthalpy changes in systems. Although there are several studies focused on identifying student alternative conceptions and misunderstandings of this subject, studies on preventing the formation of these alternative conceptions are limited.
Alternative approaches to plasma confinement
NASA Technical Reports Server (NTRS)
Roth, J. R.
1977-01-01
The potential applications of fusion reactors, the desirable properties of reactors intended for various applications, and the limitations of the Tokamak concept are discussed. The principles and characteristics of 20 distinct alternative confinement concepts are described, each of which may be an alternative to the Tokamak. The devices are classed as Tokamak-like, stellarator-like, mirror machines, bumpy tori, electrostatically assisted, migma concept, and wall-confined plasma.
The coexistence of alternative and scientific conceptions in physics
NASA Astrophysics Data System (ADS)
Ozdemir, Omer F.
The purpose of this study was to inquire about the simultaneous coexistence of alternative and scientific conceptions in the domain of physics. This study was particularly motivated by several arguments put forward in opposition to the Conceptual Change Model. In the simplest form, these arguments state that people construct different domains of knowledge and different modes of perception in different situations. Therefore, holding different conceptualizations is unavoidable and expecting a replacement in an individual's conceptual structure is not plausible in terms of instructional practices. The following research questions were generated to inquire about this argument: (1) Do individuals keep their alternative conceptions after they have acquired scientific conceptions? (2) Assuming that individuals who acquired scientific conceptions also have alternative conceptions, how are these different conceptions nested in their conceptual structure? (3) What kind of knowledge, skills, and reasoning are necessary to transfer scientific principles instead of alternative ones in the construction of a valid model? Analysis of the data collected from the non-physics group indicated that the nature of alternative conceptions is framed by two types of reasoning: reasoning by mental simulation and semiformal reasoning. Analysis of the data collected from the physics group revealed that mental images or scenes feeding reasoning by mental simulation had not disappeared after the acquisition of scientific conceptions. The analysis of data also provided enough evidence to conclude that alternative principles feeding semiformal reasoning have not necessarily disappeared after the acquisition of scientific conceptions. However, in regard to semiformal reasoning, compartmentalization was not as clear as the case demonstrated in reasoning by mental simulation; instead semiformal and scientific reasoning are intertwined in a way that the components of semiformal reasoning can easily take their place among the components of scientific reasoning. In spite of the fact that the coexistence of multiple conceptions might obstruct the transfer of scientific conceptions in problem-solving situations, several factors stimulating the use of scientific conceptions were noticed explicitly. These factors were categorized as follows: (a) the level of individuals' domain specific knowledge in the corresponding field, (b) the level of individuals' knowledge about the process of science (how science generates its knowledge claims), (c) the level of individuals' awareness of different types of reasoning and conceptions, and (d) the context in which the problem is situated. (Abstract shortened by UMI.)
Decision making by superimposing information from parallel cognitive channels
NASA Astrophysics Data System (ADS)
Aityan, Sergey K.
1993-08-01
A theory of decision making with perception through parallel information channels is presented. Decision making is considered a parallel competitive process. Every channel can provide confirmation or rejection of a decision concept. Different channels provide different impact on the specific concepts caused by the goals and individual cognitive features. All concepts are divided into semantic clusters due to the goals and the system defaults. The clusters can be alternative or complimentary. The 'winner-take-all' concept nodes firing takes place within the alternative cluster. Concepts can be independently activated in the complimentary cluster. A cognitive channel affects a decision concept by sending an activating or inhibitory signal. The complimentary clusters serve for building up complex concepts by superimposing activation received from various channels. The decision making is provided by the alternative clusters. Every active concept in the alternative cluster tends to suppress the competitive concepts in the cluster by sending inhibitory signals to the other nodes of the cluster. The model accounts for a time delay in signal transmission between the nodes and explains decreasing of the reaction time if information is confirmed by different channels and increasing of the reaction time if deceiving information received from the channels.
The conception of the alternative and the decision to divorce.
Kalb, M
1983-07-01
Despite soaring divorce rates and the effect of divorce on the individual, family, and society, professional scientific literature examining the factors governing the decision to divorce has been scant. The author suggests that the key variable affecting the decision to divorce can best be understood through an exploration of the individual's conception of the alternative. The factors that comprise the conception of the alternative are discussed and the problems inherent in its valid construction by the patient are examined. The therapeutic implementation of this conception is outlined.
2003-09-12
wetlands for preliminary treatment of sediment, oil, and grease prior to discharging into the Rouge River. While mitigating storm water quality and...land uses. While Alternative 2 and 3 have similar habitat enhancement features, Alternative 2 has much more measurable storm water quality benefits...sediment, oil, and grease prior to discharging into the Rouge River. While mitigating storm water quality and quantity impacts, this alternative
ERIC Educational Resources Information Center
McClary, LaKeisha M.; Bretz, Stacey Lowery
2012-01-01
The central goal of this study was to create a new diagnostic tool to identify organic chemistry students' alternative conceptions related to acid strength. Twenty years of research on secondary and college students' conceptions about acids and bases has shown that these important concepts are difficult for students to apply to qualitative problem…
Narrating Neoliberalism: Alternative Education Teachers' Conceptions of Their Changing Roles
ERIC Educational Resources Information Center
Golden, Noah Asher
2018-01-01
The signifier "alternative" in education has largely shifted from progressive or humanizing pedagogies to deficit framings requiring alternate graduation criteria. This development is part of broader neoliberal educational reform efforts that disrupt longstanding conceptions of teachers' roles. This study serves to investigate long-term…
Automated Platform Management System Scheduling
NASA Technical Reports Server (NTRS)
Hull, Larry G.
1990-01-01
The Platform Management System was established to coordinate the operation of platform systems and instruments. The management functions are split between ground and space components. Since platforms are to be out of contact with the ground more than the manned base, the on-board functions are required to be more autonomous than those of the manned base. Under this concept, automated replanning and rescheduling, including on-board real-time schedule maintenance and schedule repair, are required to effectively and efficiently meet Space Station Freedom mission goals. In a FY88 study, we developed several promising alternatives for automated platform planning and scheduling. We recommended both a specific alternative and a phased approach to automated platform resource scheduling. Our recommended alternative was based upon use of exactly the same scheduling engine in both ground and space components of the platform management system. Our phased approach recommendation was based upon evolutionary development of the platform. In the past year, we developed platform scheduler requirements and implemented a rapid prototype of a baseline platform scheduler. Presently we are rehosting this platform scheduler rapid prototype and integrating the scheduler prototype into two Goddard Space Flight Center testbeds, as the ground scheduler in the Scheduling Concepts, Architectures, and Networks Testbed and as the on-board scheduler in the Platform Management System Testbed. Using these testbeds, we will investigate rescheduling issues, evaluate operational performance and enhance the platform scheduler prototype to demonstrate our evolutionary approach to automated platform scheduling. The work described in this paper was performed prior to Space Station Freedom rephasing, transfer of platform responsibility to Code E, and other recently discussed changes. We neither speculate on these changes nor attempt to predict the impact of the final decisions. As a consequence some of our work and results may be outdated when this paper is published.
ICT and Constructivist Strategies Instruction for Science and Mathematics Education
ERIC Educational Resources Information Center
Kong, Ng Wai; Lai, Kong Sow
2005-01-01
Concept learning in science and mathematics had often times been taught based on assumptions of alternative concepts or even in some instances based on misconceptions. Some educational researchers favour a constructivist approach in teaching science and mathematics. The constructivist literature existing makes use of alternative conceptions as…
ERIC Educational Resources Information Center
Bledsoe, Karen E.; Flick, Lawrence
2012-01-01
This phenomenographic study documented changes in student-held electrical concepts the development of meaningful learning among students with both low and high prior knowledge within a problem-based learning (PBL) undergraduate electrical engineering course. This paper reports on four subjects: two with high prior knowledge and two with low prior…
ERIC Educational Resources Information Center
García-Carmona, Antonio; Criado, Ana M.; Cruz-Guzmán, Marta
2018-01-01
A diagnostic study is presented of the prior experiences, conceptions, and pedagogical valuations of prospective primary teachers (PPTs) about experimental activities (ExA's) in science education. The participants were 121 PPTs who, in small teams, responded to various questions related to ExA. Their responses were analysed interpretively with…
ERIC Educational Resources Information Center
Oyinloye, Olu; Popoola, Abiodun A.
2013-01-01
This paper investigates the activation of students' prior knowledge for the development of vocabulary, concepts and mathematics. It has been observed that many secondary school students are not performing well in the examination conducted by the West African Examinations Council and National Examinations Council of Nigeria. The situation became…
Satellite Power Systems (SPS) Concept Definition Study. Volume 1: Executive Summary
NASA Technical Reports Server (NTRS)
Hanley, G.
1978-01-01
The evolution of a total satellite power is described as well as major subsystem alternatives. Trade study results are given for satellite concepts, ground receiving antennas, satellite construction sites, and transportation. Point design definition, end-to-end analysis, and programmatics are covered. The GaAlAs photovoltaic concept is recommended as the current preliminary baseline satellite concept with silicon photovoltaic and Rankine cycle solar-thermal concepts as viable alternatives. Geosynchronous orbit is preferred for the construction of the satellite. A horizontal takeoff and landing air breathing rocket HLLV concept is preferred for earth-to-LEO transportation, with vertical takeoff options as viable alternatives. An argon electric orbit transfer vehicle is preferred for cargo transport from LEO and GEO orbit, and a chemical LH2/L02, two-stage orbit transfer vehicle is recommended for crew transport. A stripline rectenna array is the current preferred concept.
ERIC Educational Resources Information Center
Friedrichsen, Patricia J.; Abell, Sandra K.; Pareja, Enrique M.; Brown, Patrick L.; Lankford, Deanna M.; Volkmann, Mark J.
2009-01-01
Alternative certification programs (ACPs) have been proposed as a viable way to address teacher shortages, yet we know little about how teacher knowledge develops within such programs. The purpose of this study was to investigate prior knowledge for teaching among students entering an ACP, comparing individuals with teaching experience to those…
Shift of Meaning and Students' Alternative Concepts
ERIC Educational Resources Information Center
Schmidt, Hans-Jurgen; Volke, Dagmar
2003-01-01
The purpose of the study was to establish a relationship between the shift of meaning of the concept oxidation that has taken place during the historical development, and students' alternative concepts. First Examination Board papers were examined. The result enabled us to specify the research question. In the main part of the study,…
ERIC Educational Resources Information Center
Cakmakci, Gultekin
2010-01-01
This study identifies some alternative conceptions of chemical kinetics held by secondary school and undergraduate students (N = 191) in Turkey. Undergraduate students who participated are studying to become chemistry teachers when they graduate. Students' conceptions about chemical kinetics were elicited through a series of written tasks and…
The Problems of "Competence" and Alternatives from the Scandinavian Perspective of "Bildung"
ERIC Educational Resources Information Center
Willbergh, Ilmi
2015-01-01
The paper aims to show how competence as an educational concept for the 21st century is struggling with theoretical problems for which the concept of "Bildung" in the European tradition can offer alternatives, and to discuss the possibility of developing a sustainable educational concept from the perspectives of competence and…
Conceptions of Teaching Science Held by Novice Teachers in an Alternative Certification Program
ERIC Educational Resources Information Center
Koballa, Thomas R.; Glynn, Shawn M.; Upson, Leslie
2005-01-01
Case studies to investigate the conceptions of teaching science held by three novice teachers participating in an alternative secondary science teacher certification program were conducted, along with the relationships between their conceptions of science teaching and their science teaching practice. Data used to build the cases included the…
ERIC Educational Resources Information Center
Dong, Yu Ren
2013-01-01
This article highlights how English language learners' (ELLs) prior knowledge can be used to help learn science vocabulary. The article explains that the concept of prior knowledge needs to encompass the ELL student's native language, previous science learning, native literacy skills, and native cultural knowledge and life experiences.…
Effects of Prior Knowledge and Concept-Map Structure on Disorientation, Cognitive Load, and Learning
ERIC Educational Resources Information Center
Amadieu, Franck; van Gog, Tamara; Paas, Fred; Tricot, Andre; Marine, Claudette
2009-01-01
This study explored the effects of prior knowledge (high vs. low; HPK and LPK) and concept-map structure (hierarchical vs. network; HS and NS) on disorientation, cognitive load, and learning from non-linear documents on "the infection process of a retrograde virus (HIV)". Participants in the study were 24 adults. Overall subjective ratings of…
NASA Astrophysics Data System (ADS)
Rezanov, I. A.
Initially the hypotheses of Kant, Laplace, and other authors implied homogeneous accretion of planets from uniform material. O. Yu. Schmidt shared this idea. The idea of heterogeneous accretion was proposed in the mid-1940s by V. G. Fesenkov, who demonstrated that the iron cores of planets started to form prior to their silicate mantles. The obvious increase in average planet density with decreasing distance from the Sun suggests that the protoplanetary nebula was also heterogeneous - iron concentrated closer to the Sun, probably under the effect of its magnetic field. In the second half of the 20th century, planetary cosmogony developed against the background of continuous dispute between the adherents of homogeneous and heterogeneous planetary accretion. The confrontation still exists, although arguments in favour of heterogeneous accretion increase in weight. The dilemma under discussion is directly related to modern tectonic concepts, because it is necessary to find an answer to the question whether the core originated from the differentiation of the Earth's material or our planet had a core from the beginning.
Enhanced LOD Concepts for Virtual 3d City Models
NASA Astrophysics Data System (ADS)
Benner, J.; Geiger, A.; Gröger, G.; Häfele, K.-H.; Löwner, M.-O.
2013-09-01
Virtual 3D city models contain digital three dimensional representations of city objects like buildings, streets or technical infrastructure. Because size and complexity of these models continuously grow, a Level of Detail (LoD) concept effectively supporting the partitioning of a complete model into alternative models of different complexity and providing metadata, addressing informational content, complexity and quality of each alternative model is indispensable. After a short overview on various LoD concepts, this paper discusses the existing LoD concept of the CityGML standard for 3D city models and identifies a number of deficits. Based on this analysis, an alternative concept is developed and illustrated with several examples. It differentiates between first, a Geometric Level of Detail (GLoD) and a Semantic Level of Detail (SLoD), and second between the interior building and its exterior shell. Finally, a possible implementation of the new concept is demonstrated by means of an UML model.
Some Student Conceptions of Electromagnetic Induction
NASA Astrophysics Data System (ADS)
Thong, Wai Meng; Gunstone, Richard
2008-01-01
Introductory electromagnetism is a central part of undergraduate physics. Although there has been some research into student conceptions of electromagnetism, studies have been sparse and separated. This study sought to explore second year physics students’ conceptions of electromagnetism, to investigate to what extent the results from the present study are similar to these results from other studies, and to uncover any new forms of alternative conceptions. Data for this study came from 15 in-depth interviews. Three previously unreported alternative conceptions were identified in the study: 1) induced current varies proportionately with current in solenoid; 2) there must be contact between magnetic flux and the external coil in order for any emf to be induced in the coil; 3) coulombic or electrostatic potential difference is present in an induced electric field. These alternative conceptions were manifested in these students’ explanations of electromagnetic phenomena presented to them during the interviews.
Tsagkari, Mirela; Couturier, Jean-Luc; Kokossis, Antonis; Dubois, Jean-Luc
2016-09-08
Biorefineries offer a promising alternative to fossil-based processing industries and have undergone rapid development in recent years. Limited financial resources and stringent company budgets necessitate quick capital estimation of pioneering biorefinery projects at the early stages of their conception to screen process alternatives, decide on project viability, and allocate resources to the most promising cases. Biorefineries are capital-intensive projects that involve state-of-the-art technologies for which there is no prior experience or sufficient historical data. This work reviews existing rapid cost estimation practices, which can be used by researchers with no previous cost estimating experience. It also comprises a comparative study of six cost methods on three well-documented biorefinery processes to evaluate their accuracy and precision. The results illustrate discrepancies among the methods because their extrapolation on biorefinery data often violates inherent assumptions. This study recommends the most appropriate rapid cost methods and urges the development of an improved early-stage capital cost estimation tool suitable for biorefinery processes. © 2015 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.
Students' Alternative Conceptions about Electricity and Effect of Inquiry-Based Teaching Strategies
ERIC Educational Resources Information Center
Afra, Nada Chatila; Osta, Iman; Zoubeir, Wassim
2009-01-01
This study attempted to investigate the alternative conceptions that a group of 12 Lebanese students in a grade 9 class hold about electricity. It also attempted to evaluate learning outcomes of implementing in that class an inquiry-based module for the acquisition of conceptual understanding of basic concepts in electricity. Fourteen mostly…
ERIC Educational Resources Information Center
Abdullah, Nurdiana; Surif, Johari; Ismail, Syuhaida
2016-01-01
The study was carried out to identify the alternative frameworks on the concept of condensation at submicroscopic level among secondary school students (N = 324). Data was collected by using the qualitative method through the Understanding Test on the Concept of Matter at Submicroscopic Level which consisted of 10 open-ended questions. The…
ERIC Educational Resources Information Center
Wong, Chee Leong; Chu, Hye-Eun; Yap, Kueh Chin
2016-01-01
Currently, there is no agreement among scientists and science educators on whether heat should be defined as a "process of energy transfer" or "form of energy." For example, students may conceive of heat as "molecular kinetic energy," but the interpretation of this alternative conception is dependent on educational…
Fill Malfertheiner, Sara; Gutknecht, Dagmar; Bals-Pratsch, Monika
2017-01-01
Background A hyperglycemic metabolic status with insulin resistance can have a negative effect on fertility and pregnancy outcomes. The aim of this retrospective study was to investigate disorders of glucose and insulin metabolism in women wanting to conceive who conceived spontaneously prior to planned assisted reproduction (ART). Associated risk factors of patients in terms of live births and miscarriages were also analyzed. Method Out of total study population of 589 pregnancies, the pregnancies of 129 women wishing to have children who conceived spontaneously prior to planned ART were analyzed in more detail. A 75 g OGTT (OGTT: oral glucose tolerance test) was carried out prior to conception and after determination of pregnancy, including glucose measurement and testing of insulin resistance. If anomalies or risk factors for gestational diabetes (GDM) were detected, patients received metformin therapy prior to conception (off-label use). The course and outcome of pregnancies in the defined cohort were recorded. Results The rate of spontaneous conception before planned ART after treatment for disorders of glucose/insulin metabolism was 21.9% (n = 129/589). 66.7% of the 129 pregnancies resulted in a live birth, 32 patients had a miscarriage. 76.0% of patients were treated with metformin (off-label use) for polycystic ovary syndrome (PCOS), positive risk profile for GDM, or abnormal glucose/insulin metabolism prior to conception. 55.8% of the cohort developed GDM. The insulin requirements of patients with GDM differed significantly depending on their metformin intake. 24.6% of GDM patients receiving metformin treatment developed GDM requiring insulin treatment compared to 53.8% who did not receive metformin medication. The PCOS rate in the study population who had live births was significantly higher (57.0%) than in the group who had miscarriages (31.3%). There were no significant differences with regard to rate of live births and rate of miscarriages with/without metformin treatment and GDM and metformin intake. Conclusion The high rate of spontaneous conceptions in the cohort of women wishing to conceive emphasizes the importance of optimizing glucose/insulin metabolism prior to conception. The high rate of GDM in a cohort of pregnant women with a history of sterility also emphasizes the importance of expanding diagnostic testing for sterility to include the investigation of glucose metabolism and testing for insulin resistance. It is possible that PCOS patients in particular could benefit from treatment with metformin prior to conception, and this could explain the high rate of live births in this patient cohort. PMID:29276231
ERIC Educational Resources Information Center
Yanchar, Stephen C.; Faulconer, James E.
2011-01-01
This article presents the concept of facilitative theorizing as an alternative to prescriptive and descriptive theory in educational technology. The authors contend that these traditional forms of theory do not offer sufficient assistance to practitioners as they go about everyday design work. Facilitative theorizing, as an alternative, is…
ERIC Educational Resources Information Center
Hargreaves, Jo; Blomberg, Davinia
2015-01-01
The nature of apprenticeships is changing. Increasing proportions of adult apprentices are prompting demand for various alternative pathways to completion. One option for an alternative pathway to accelerate completion is the use of recognition of prior learning (RPL) to identify existing skills and knowledge in combination with gap training. This…
NASA Technical Reports Server (NTRS)
Hays, D.
1982-01-01
Alternate thermal protection system (TPS) concepts to the Space Shuttle Orbiter were assessed. Metallic, ablator, and carbon-carbon concepts which are the result of some previous design, manufacturing and testing effort were considered. Emphasis was placed on improved TPS durability, which could potentially reduce life cycle costs and improve Orbiter operational characteristics. Integrated concept/orbiter point designs were generated and analyzed on the basis of Shuttle design environments and criteria. A merit function evaluation methodology based on mission impact, life cycle costs, and risk was developed to compare the candidate concepts and to identify the best alternate. Voids and deficiencies in the technology were identified, along with recommended activities to overcome them. Finally, programmatic plans, including ROM costs and schedules, were developed for all activities required to bring the selected alternate system up to operational readiness.
Perez, Kathryn E.; Price, Rebecca M.
2014-01-01
Despite the impact of genetics on daily life, biology undergraduates understand some key genetics concepts poorly. One concept requiring attention is dominance, which many students understand as a fixed property of an allele or trait and regularly conflate with frequency in a population or selective advantage. We present the Dominance Concept Inventory (DCI), an instrument to gather data on selected alternative conceptions about dominance. During development of the 16-item test, we used expert surveys (n = 12), student interviews (n = 42), and field tests (n = 1763) from introductory and advanced biology undergraduates at public and private, majority- and minority-serving, 2- and 4-yr institutions in the United States. In the final field test across all subject populations (n = 709), item difficulty ranged from 0.08 to 0.84 (0.51 ± 0.049 SEM), while item discrimination ranged from 0.11 to 0.82 (0.50 ± 0.048 SEM). Internal reliability (Cronbach's alpha) was 0.77, while test–retest reliability values were 0.74 (product moment correlation) and 0.77 (intraclass correlation). The prevalence of alternative conceptions in the field tests shows that introductory and advanced students retain confusion about dominance after instruction. All measures support the DCI as a useful instrument for measuring undergraduate biology student understanding and alternative conceptions about dominance. PMID:26086665
Busch, Alexander J; Morey, Leslie C; Hopwood, Christopher J
2017-01-01
Section III of the Diagnostic and Statistical Manual of Mental Disorders (5th ed. [DSM-5]; American Psychiatric Association, 2013) contains an alternative model for the diagnosis of personality disorder involving the assessment of 25 traits and a global level of overall personality functioning. There is hope that this model will be increasingly used in clinical and research settings, and the ability to apply established instruments to assess these concepts could facilitate this process. This study sought to develop scoring algorithms for these alternative model concepts using scales from the Personality Assessment Inventory (PAI). A multiple regression strategy used to predict scores in 2 undergraduate samples on DSM-5 alternative model instruments: the Personality Inventory for the DSM-5 (PID-5) and the General Personality Pathology scale (GPP; Morey et al., 2011 ). These regression functions resulted in scores that demonstrated promising convergent and discriminant validity across the alternative model concepts, as well as a factor structure in a cross-validation sample that was congruent with the putative structure of the alternative model traits. Results were linked to the PAI community normative data to provide normative information regarding these alternative model concepts that can be used to identify elevated traits and personality functioning level scores.
Influence of a CIDR prior to bull breeding on pregnancy rates and subsequent calving distribution.
Lamb, G C; Dahlen, C R; Vonnahme, K A; Hansen, G R; Arseneau, J D; Perry, G A; Walker, R S; Clement, J; Arthington, J D
2008-11-01
We determined whether insertion of a CIDR for 7 days prior to the breeding season enhanced pregnancy rates and altered the date of conception in suckled beef cows mated naturally. Suckled beef cows (n=2033) from 15 locations were randomly assigned to one of two treatments: (1) cows received a CIDR 7 days prior to the breeding season for 7 days (CIDR; n=999); (2) cows received no treatment (Control; n=1034). On the first day of the breeding season bulls were introduced to herds at a rate of 15-25 cows per yearling bull or 20-30 cows per mature bull. Pregnancy status and the date of conception were determined via transrectal ultrasonography at 56 and 120 days after initiation of the breeding season. Overall pregnancy rates ranged from 59.3 to 98.9% among the 15 locations. The percentage of cows becoming pregnant during the first 30 days of the breeding season was similar between CIDR (68.2%) and Control (66.7%) cows, and overall pregnancy rates were similar between CIDR (88.9%) and Control (88.6%) cows. The average day of conception after initiation of the breeding season was shorter (P<0.01) for CIDR (20.1+/-0.8 days) compared to Control cows (23.2+/-0.8 days). Of cows conceiving during the breeding season, more (P<0.05) CIDR cows (35.9%) conceived during the first 10 days of the breeding season than Control cows (30.8%). Neither body condition score and nor parity affected pregnancy rates or days to conception, whereas pregnancy rates and days to conception were affected (P<0.01) by location and days postpartum. Days to conception were greater for cows that calved within 40 days (31.6+/-1.2 days) of initiation of the breeding season compared to cows calving between 40 and 50 days (25.3+/-1.2 days) prior to initiation of the breeding season, which were greater than those cows calving between 50-60 days (20.0+/-0.8 days) and 60-70 days (21.3+/-1.0 days) prior to initiation of the breeding season. Cows calving greater than 70 days (17.3+/-1.5 days) from initiation of the breeding season had the shortest interval to conception. We concluded that insertion of a CIDR prior to the breeding season failed to increase overall pregnancy rates, but did influence the average day of conception.
Fostering radical conceptual change through dual-situated learning model
NASA Astrophysics Data System (ADS)
She, Hsiao-Ching
2004-02-01
This article examines how the Dual-Situated Learning Model (DSLM) facilitates a radical change of concepts that involve the understanding of matter, process, and hierarchical attributes. The DSLM requires knowledge of students' prior beliefs of science concepts and the nature of these concepts. In addition, DSLM also serves two functions: it creates dissonance with students' prior knowledge by challenging their epistemological and ontological beliefs about science concepts, and it provides essential mental sets for students to reconstruct a more scientific view of the concepts. In this study, the concept heat transfer: heat conduction and convection, which requires an understanding of matter, process, and hierarchical attributes, was chosen to examine how DSLM can facilitate radical conceptual change among students. Results show that DSLM has great potential to foster a radical conceptual change process in learning heat transfer. Radical conceptual change can definitely be achieved and does not necessarily involve a slow or gradual process.
ERIC Educational Resources Information Center
Yen, Chiung-Fen; Yao, Tsung-Wei; Chiu, Yu-Chih
2004-01-01
This study examined students' alternative conceptions of reptiles and amphibians and the extent to which these conceptions remain intact through the elementary (grades 4 and 6), junior, and senior high school years. We administered multiple-choice and free-response instruments to a total of 513 students and interviewed at least 20 students at each…
NASA Astrophysics Data System (ADS)
Karim, Nafis I.; Maries, Alexandru; Singh, Chandralekha
2018-06-01
The Conceptual Survey of Electricity and Magnetism (CSEM) has been used to assess student understanding of introductory concepts of electricity and magnetism because many of the items on the CSEM have strong distractor choices which correspond to students' alternate conceptions. Instruction is unlikely to be effective if instructors do not know the common alternate conceptions of introductory physics students and explicitly take into account common student difficulties in their instructional design. Here, we discuss research involving the CSEM to evaluate one aspect of the pedagogical content knowledge of teaching assistants (TAs): knowledge of introductory students' alternate conceptions in electricity and magnetism as revealed by the CSEM. For each item on the CSEM, the TAs were asked to identify the most common incorrect answer choice selected by introductory physics students if they did not know the correct answer after traditional instruction. Then, we used introductory student CSEM post-test data to assess the extent to which TAs were able to identify the most common alternate conception of introductory students in each question on the CSEM. We find that the TAs were thoughtful when attempting to identify common student difficulties and they enjoyed learning about student difficulties this way. However, they struggled to identify many common difficulties of introductory students that persist after traditional instruction. We discuss specific alternate conceptions that persist after traditional instruction, the extent to which TAs were able to identify them, and results from think-aloud interviews with TAs which provided valuable information regarding why the TAs sometimes selected certain alternate conceptions as the most common but were instead very rare among introductory students. We also discuss how tasks such as the one used in this study can be used in professional development programs to engender productive discussions about the importance of being knowledgeable about student alternate conceptions in order to help students learn. Interviews with TAs engaged in this task as well as our experience with such tasks in our professional development programs suggest that they are beneficial.
ERIC Educational Resources Information Center
Nyachwaya, James M.; Mohamed, Abdi-Rizak; Roehrig, Gillian H.; Wood, Nathan B.; Kern, Anne L.; Schneider, Jamie L.
2011-01-01
Many studies in the chemical education literature report students' alternative conceptions in chemistry and the difficulty they present for future learning. In this paper, we review existing diagnostic tools used to uncover students' alternative conceptions in chemistry and suggest that there are two fundamental issues with such instruments,…
Green Infrastructure & Sustainable Urban Land Use Decision Analysis Workshop
Introduce green infrastructure, concepts and land use alternatives, to City of Cleveland operations staff. Discuss potential of green alternatives to impact daily operations and routine maintenance activities. Tie in sustainability concepts to long-term City planning and discu...
ERIC Educational Resources Information Center
Preckel, Franzis; Schmidt, Isabelle; Stumpf, Eva; Motschenbacher, Monika; Vogl, Katharina; Schneider, Wolfgang
2017-01-01
According to the reciprocal-effects model (REM), prior academic self-concept (ASC) has a positive effect on subsequent achievement beyond what can be explained in terms of prior achievement and vice versa. The present study investigated the REM for students studying in special classes for the gifted compared to students studying in regular…
Assessment of Alternate Thermal Protection Systems for the Space Shuttle Orbiter
NASA Technical Reports Server (NTRS)
Kelly, H. N.; Webb, G. L.
1982-01-01
Candidate concepts are identified. The impact on the Shuttle Orbiter performance life cycle cost, and risk was assessed and technology advances required to bring the selected TPS to operational readiness are defined. The best system is shown to be a hybrid blend of metallic and carbon-carbon TPS concepts. These alternate concepts offer significant improvements in reusability and are mass competitive with the current ceramic tile reusable surface insulation. Programmatic analysis indicates approximately five years are required to bring the concepts to operational readiness.
Fuzzy-based propagation of prior knowledge to improve large-scale image analysis pipelines
Mikut, Ralf
2017-01-01
Many automatically analyzable scientific questions are well-posed and a variety of information about expected outcomes is available a priori. Although often neglected, this prior knowledge can be systematically exploited to make automated analysis operations sensitive to a desired phenomenon or to evaluate extracted content with respect to this prior knowledge. For instance, the performance of processing operators can be greatly enhanced by a more focused detection strategy and by direct information about the ambiguity inherent in the extracted data. We present a new concept that increases the result quality awareness of image analysis operators by estimating and distributing the degree of uncertainty involved in their output based on prior knowledge. This allows the use of simple processing operators that are suitable for analyzing large-scale spatiotemporal (3D+t) microscopy images without compromising result quality. On the foundation of fuzzy set theory, we transform available prior knowledge into a mathematical representation and extensively use it to enhance the result quality of various processing operators. These concepts are illustrated on a typical bioimage analysis pipeline comprised of seed point detection, segmentation, multiview fusion and tracking. The functionality of the proposed approach is further validated on a comprehensive simulated 3D+t benchmark data set that mimics embryonic development and on large-scale light-sheet microscopy data of a zebrafish embryo. The general concept introduced in this contribution represents a new approach to efficiently exploit prior knowledge to improve the result quality of image analysis pipelines. The generality of the concept makes it applicable to practically any field with processing strategies that are arranged as linear pipelines. The automated analysis of terabyte-scale microscopy data will especially benefit from sophisticated and efficient algorithms that enable a quantitative and fast readout. PMID:29095927
NASA Technical Reports Server (NTRS)
Wetch, J. R.
1988-01-01
The major power conversion concepts considered for the Megawatt Class Nuclear Space Power System (MCNSPS) are discussed. These concepts include: (1) Rankine alkali-metal-vapor turbine alternators; (2) in-core thermionic conversion; (3) Brayton gas turbine alternators; and (4) free piston Stirling engine linear alternators. Considerations important to the coupling of these four conversion alternatives to an appropriate nuclear reactor heat source are examined along with the comparative performance characteristics of the combined systems meeting MCNSPS requirements.
NASA Astrophysics Data System (ADS)
Weidner, Jeanne Margaret O'malley
2000-10-01
This study was motivated by some of the claims that are found in the literature on Problem-Based Learning (PBL). This instructional technique, which uses case studies as its primary instructional tool, has been advanced as an alternative to traditional instruction in order to foster more meaningful, integrative learning of scientific concepts. Several of the advantages attributed to Problem-Based Learning are that it (1) is generally preferred by students because it appears to foster a more nurturing and enjoyable learning experience, (2) fosters greater retention of knowledge and concepts acquired, and (3) results in increased ability to apply this knowledge toward solving new problems. This study examines the differences that result when students learn neuroanatomy concepts under two instructional contexts: problem solving vs. information gathering. The technological resource provided to students to support learning under each of these contexts was the multimedia program BrainStorm: An Interactive Neuroanatomy Atlas (Coppa & Tancred, 1995). The study explores the influence of context with regard to subjects' performance on objective post-tests, organization of knowledge as measured by Pathfinder Networks, differential use of the multimedia software and discourse differences emerging from the transcripts. The findings support previous research in the literature that problem-solving results in less knowledge acquisition in the short term, greater retention of material over time, and a subjects' preference for the method. However, both the degree of retention and preference were influenced by subjects' prior knowledge of the material in the exercises, as there was a significant difference in performance between the two exercises: for the exercise about which subjects appeared to have greater background information, memory decay was less, and subject attitude toward the problem solving instructional format was more favorable, than for the exercise for which subjects had less prior knowledge. Subjects also used the software differently under each format with regard to modules accessed, time spent in modules, and types of information sought. In addition, analyses of the transcripts showed more numerous occurrences of explanations and summarizations in the problem-solving context, compared to the information gathering context. The attempts to show significant differences between the contexts by means of Pathfinder analyses were less than successful.
NASA Astrophysics Data System (ADS)
Xu, Robert S.; Michailovich, Oleg V.; Solovey, Igor; Salama, Magdy M. A.
2010-03-01
Prostate specific antigen density is an established parameter for indicating the likelihood of prostate cancer. To this end, the size and volume of the gland have become pivotal quantities used by clinicians during the standard cancer screening process. As an alternative to manual palpation, an increasing number of volume estimation methods are based on the imagery data of the prostate. The necessity to process large volumes of such data requires automatic segmentation algorithms, which can accurately and reliably identify the true prostate region. In particular, transrectal ultrasound (TRUS) imaging has become a standard means of assessing the prostate due to its safe nature and high benefit-to-cost ratio. Unfortunately, modern TRUS images are still plagued by many ultrasound imaging artifacts such as speckle noise and shadowing, which results in relatively low contrast and reduced SNR of the acquired images. Consequently, many modern segmentation methods incorporate prior knowledge about the prostate geometry to enhance traditional segmentation techniques. In this paper, a novel approach to the problem of TRUS segmentation, particularly the definition of the prostate shape prior, is presented. The proposed approach is based on the concept of distribution tracking, which provides a unified framework for tracking both photometric and morphological features of the prostate. In particular, the tracking of morphological features defines a novel type of "weak" shape priors. The latter acts as a regularization force, which minimally bias the segmentation procedure, while rendering the final estimate stable and robust. The value of the proposed methodology is demonstrated in a series of experiments.
ERIC Educational Resources Information Center
Perkinson, Henry
1978-01-01
Describes the theories of Karl Popper regarding scientific knowledge and scientific methodology; tells how the Popper-Darwinian theory of growth of knowledge offers an alternative nonauthoritarian conception of the educational process, and thus an alternative conception of the functions of the teacher and the school. (GT)
ERIC Educational Resources Information Center
Eymur, Guluzar; Çetin, Pinar; Geban, Ömer
2013-01-01
The purpose of this study was to analyze and compare the alternative conceptions of high school students and preservice teachers on the concept of atomic size. The Atomic Size Diagnostic Instrument was developed; it is composed of eight, two-tier multiple-choice items. The results of the study showed that as a whole 56.2% of preservice teachers…
ERIC Educational Resources Information Center
Lucero, Margaret M.; Petrosino, Anthony J.
2017-01-01
The Conceptual Inventory of Natural Selection (CINS) is an example of a research-based instrument that assesses conceptual understanding in an area that contains well-documented alternative conceptions. Much of the CINS's use and original validation has been relegated to undergraduate settings, but the information learned from student responses on…
Steam Oxidation Testing in the Severe Accident Test Station
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pint, Bruce A.; McMurray, Jake W.
2016-08-01
Since 2011, Oak Ridge National Laboratory (ORNL) has been conducting high temperature steam oxidation testing of candidate alloys for accident tolerant fuel (ATF) cladding. These concepts are designed to enhance safety margins in light water reactors (LWR) during severe accident scenarios. In the US ATF community, the Severe Accident Test Station (SATS) has been evaluating candidate materials (including coatings) since 2012. Compared to the current UO 2/Zr-based alloy fuel system, alternative cladding materials need to offer slower oxidation kinetics and a smaller enthalpy of oxidation in order to significantly reduce the rate of heat and hydrogen generation in the coremore » during a coolant-limited severe accident. The steam oxidation behavior of candidate materials is a key metric in the evaluation of ATF concepts and also an important input into models. However, prior modeling work of FeCrAl cladding has used incomplete information on the physical properties of FeCrAl. Also, the steam oxidation data being collected at 1200°-1700°C is unique as no prior work has considered steam oxidation of alloys at such high temperatures. In some cases, the results have been difficult to interpret and more fundamental information is needed such as the stability of alumina in flowing steam at 1400°-1500°C. This report summarizes recent work to measure the steam oxidation kinetics of candidate alloys, the evaporation rate of alumina in steam and the development of integral data on FeCrAl compared to conventional Zr-based cladding.« less
Study of alternate space shuttle concepts
NASA Technical Reports Server (NTRS)
1971-01-01
A study of alternate space shuttle concepts was conducted to examine the stage-and-one-half concept and its potential for later conversion and use in the two stage reusable shuttle system. A study of external hydrogen tank concepts was conducted to determine the issues involved in the design and production of a low-cost expendable tank system. The major objectives of the study were to determine: (1) realistic drop tank program cost estimates, (2) estimated drop tank program cost for selected specific designs, and (3) change in program cost due to variations in design and manufacturing concepts and changes in program assumptions.
Experience-based Learning in Acadia National Park: a Successful, Long-running, Model Field Course
NASA Astrophysics Data System (ADS)
Connaughton, M.
2015-12-01
This two-week field course has been offered alternate summers since 2000 in Acadia National Park on Mount Desert Island, Maine and addresses the geological history, physical and biological oceanography and principles of community ecology applicable to terrestrial and/or marine communities of coastal Maine. The course is often transformative and deeply meaningful to the students, many of whom have limited travel experience. The essential components of experience-based learning are well represented in this class with multiple opportunities for abstract conceptualization, active experimentation, concrete hands-on experiences and reflective observation built into the course. Each day begins with a lecture introducing concepts, which are then made concrete though daily field trips (4-8 hours in duration) into the park that include rigorous hiking, some kayaking and one commercial nature cruise. Field trips include hands-on experience with lecture concepts, on-site lessons in field methods, and data collection for independent projects. Each field trip is tied to a specific independent project, which are generated by the instructor, but self-selected by the students. Every student is actively involved in data collection during each field trip, with one student in charge of the collection each day. Daily guided journaling in three parts (scientific, personal and creative) and evening discussions provide ample opportunity for the student to reflect on the scientific content of the course, examine their personal reactions to what they have experienced and to be creative, sharing prior experiences, prior learning and their personalities. The course includes two exams, each following a week of lecture and field experiences. Independent research projects include the production of a manuscript-formatted report complete with statistical analysis of the data and a literature-based discussion of the conclusions. The combination of experiential reinforcement of concepts, abundant opportunity for written and spoken reflection, the beauty of the setting, the challenges of working in the field and the resultant bonding of the students and instructors provide a highly effective and unforgettable learning experience.
Models of conceptual understanding in human respiration and strategies for instruction
NASA Astrophysics Data System (ADS)
Rea-Ramirez, Mary Anne
Prior research has indicated that students of all ages show little understanding of respiration beyond breathing in and out and the need for air to survive. This occurs even after instruction with alternative conceptions persisting into adulthood. Whether this is due to specific educational strategies or to the level of difficulty in understanding a complex system is an important question. The purpose of this study was to obtain a deeper understanding of middle school students' development of mental models of human respiration. The study was composed of two major parts, one concerned with documenting and analyzing how students learn, and one concerned with measuring the effect of teaching strategies. This was carried out through a pre-test, "learning aloud" case studies in which students engaged in one-on-one tutoring interviews with the researcher, and a post-test. Transcript data from the intervention and post-test indicates that all students in this study were successful in constructing mental models of a complex concept, respiration, and in successfully applying these mental models to transfer problems. Differences in the pretest and posttest means were on the order of two standard deviations in size. While findings were uncovered in the use of a variety of strategies, possibly most interesting are the new views of analogies as an instructional strategy. Some analogies appear to be effective in supporting construction of visual/spatial features. Providing multiple, simple analogies that allow the student to construct new models in small steps, using student generated analogies, and using analogies to determine prior knowledge may also increase the effectiveness of analogies. Evidence suggested that students were able to extend the dynamic properties of certain analogies to the dynamics of the target conception and that this, in turn, allowed students to use the new models to explain causal relationships and give new function to models. This suggests that construction of causal, dynamic mental models is supported by the use of analogies containing dynamic and causal relationships.
Endometrial Shedding Effect on Conception and Live Birth in Women With Polycystic Ovary Syndrome
Diamond, Michael P.; Kruger, Michael; Santoro, Nanette; Zhang, Heping; Casson, Peter; Schlaff, William; Coutifaris, Christos; Brzyski, Robert; Christman, Gregory; Carr, Bruce R.; McGovern, Peter G.; Cataldo, Nicholas A.; Steinkampf, Michael P.; Gosman, Gabriella G.; Nestler, John E.; Carson, Sandra; Myers, Evan E.; Eisenberg, Esther; Legro, Richard S.
2013-01-01
Objective To estimate whether progestin-induced endometrial shedding, prior to ovulation induction with clomiphene citrate, metformin, or a combination of both, affects ovulation, conception, and live birth rates in women with polycystic ovary syndrome (PCOS). Methods A secondary analysis of the data from 626 women with PCOS from the National Institutes of Child Health and Human Development Cooperative Reproductive Medicine Network trial was performed. Women had been randomized to up to six cycles of clomiphene citrate alone, metformin alone, or clomiphene citrate plus metformin. Women were assessed for occurrence of ovulation, conception, and live birth in relation to prior bleeding episodes (after either ovulation or exogenous progestin-induced withdrawal bleed). Results While ovulation rates were higher in cycles preceded by spontaneous endometrial shedding than after anovulatory cycles (with or without prior progestin withdrawal), both conception and live birth rates were significantly higher after anovulatory cycles without progestin-induced withdrawal bleeding (live birth per cycle: spontaneous menses 2.2%; anovulatory with progestin withdrawal 1.6%; anovulatory without progestin withdrawal 5.3%; p<0.001). The difference was more marked when rate was calculated per ovulation (live birth per ovulation: spontaneous menses 3.0%; anovulatory with progestin withdrawal 5.4%; anovulatory without progestin withdrawal 19.7%; p < .001). Conclusion Conception and live birth rates are lower in women with PCOS after a spontaneous menses or progestin-induced withdrawal bleeding as compared to anovulatory cycles without progestin withdrawal. The common clinical practice of inducing endometrial shedding with progestin prior to ovarian stimulation may have an adverse effect on rates of conception and live birth in anovulatory women with PCOS. PMID:22525900
Language-Mediated Concept Learning.
ERIC Educational Resources Information Center
Follettie, Joseph F.
The conditions whereby a concept might be learned on the basis of a language mediation process prior to the inductive learning of subordinate concepts are sketched. The view is expressed that grammar treatments which are apt to primary education should be defined on the basis of a pedagogy's needs for linguistic characterizations of concepts to be…
Examining the progression and consistency of thermal concepts: a cross-age study
NASA Astrophysics Data System (ADS)
Adadan, Emine; Yavuzkaya, Merve Nur
2018-03-01
This cross-sectional study examined how the progression and consistency of students' understanding of thermal concepts in everyday contexts changes across the grade levels. A total of 656 Turkish students from Grade 8 (age 13-14), Grade 10 (age 15-16), and the first year of college (age 19-20) participated in the study. The data were analysed using statistical procedures (descriptive and inferential). Findings indicated a substantial progression in the students' scientific understanding of thermal concepts across grade levels. In addition, the students' alternative conceptions about thermal concepts generally decreased in frequency across grade levels, but certain alternative conceptions were observed in every grade level to a similar extent. Even though the number of students who consistently used scientific ideas increased across grade levels, the number of students who consistently used non-scientific ideas decreased across grade levels. However, the number of students who used scientific and non-scientific ideas inconsistently generally increased as they progressed in the science curriculum. These findings can be associated with either fragmentation or alternative conceptions that result from the gradual enrichment processes students experience when they try to integrate scientific concepts into their conceptual frameworks.
Clinical application of hysteroscopic hydrotubation for unexplained infertility in the mare.
Inoue, Y; Sekiguchi, M
2017-11-07
Therapeutic techniques for oviductal obstruction in the mare are limited. Nonsurgical and retrograde flushing may be an attractive alternative to current treatment methods for oviductal blockage. To evaluate hysteroscopic selective hydrotubation as a treatment option for presumptive equine oviductal blockage. Retrospective case series. A quantity of 10 mL of saline was flushed through the oviducts in 28 standing sedated mares, which had reproductive histories of unexplained subfertility, by inserting a catheter into the uterotubal junction under endoscopic guidance. All mares in the study had been mated through several cycles (2-20 oestrous cycles) by known fertile stallions prior to treatment, with no evidence of conception. The average number of cycles for each mare prior to treatment was 6.5 ± 4.5. Saline was successfully infused into a total of 50 oviducts. Of 28 mares, 26 conceived after the treatment. The average number of cycles for each mare to become pregnant after treatment was 1.8 ± 0.8. Diagnosis of blocked oviducts was presumptive, and pretreatment infertility was used as the control. This study revealed that hysteroscopic hydrotubation using saline improved pregnancy rates in mares in which oviductal blockage was suspected as a cause of unexplained subfertility. © 2017 EVJ Ltd.
Study of Alternate Space Shuttle Concepts. Volume 2, Part 2: Concept Analysis and Definition
NASA Technical Reports Server (NTRS)
1971-01-01
This is the final report of a Phase A Study of Alternate Space Shuttle Concepts by the Lockheed Missiles & Space Company (LMSC) for the National Aeronautics and Space Administration George C. Marshall Space Flight Center (MSFC). The eleven-month study, which began on 30 June 1970, is to examine the stage-and-one-half and other Space Shuttle configurations and to establish feasibility, performance, cost, and schedules for the selected concepts. This final report consists of four volumes as follows: Volume I - Executive Summary, Volume II - Concept Analysis and Definition, Volume III - Program Planning, and Volume IV - Data Cost Data. This document is Volume II, Concept Analysis and Definition.
Greek Children's Alternative Conceptions on Weather and Climate.
ERIC Educational Resources Information Center
Spiropoulou, D.; Kostopoulos, D.; Jacovides, C. P.
1999-01-01
Describes a survey of Greek schoolchildren's alternative conceptions about weather and climate. Finds that misconceptions exist, including confusion between the meanings of the terms "weather" and "climate", inflated estimates of temperature, and a belief that yearly weather data define climate. Suggests ways to help students…
Liu, Bette; Roberts, Christine L; Clarke, Marilyn; Jorm, Louisa; Hunt, Jennifer; Ward, James
2013-12-01
To examine the association between prior chlamydia and gonorrhoea infections and adverse obstetric outcomes. Records of women resident in New South Wales, Australia with a singleton first birth during 1999-2008 were linked to chlamydia and gonorrhoea notifications using probabilistic linkage. Obstetric outcomes and potential confounders were ascertained from the birth record. Logistic regression, adjusted for potential confounders was used to estimate the association between a disease notification prior to the birth and adverse birth outcomes: spontaneous preterm birth (SPTB), small for gestational age (SGA) and stillbirth. Among 354 217 women, 1.0% (n=3658) had a prior chlamydia notification; 0.06% (n=196) had a prior gonorrhoea notification. The majority of notifications (>80%) occurred before the estimated conception date. 4.1% of women had a SPTB, 12.1% had a SGA baby and 0.6% of women had a stillbirth. Among women with a prior chlamydia notification, the risk of SPTB and stillbirth was increased, aOR 1.17 (95% CI 1.01 to 1.37) and aOR 1.40 (95% CI 1.00 to 1.96) respectively but there was no association with SGA, aOR 0.99 (95% CI 0.89 to 1.09). For women with gonorrhoea the risks for SPTB, stillbirth and SGA were respectively aOR 2.50 (95%CI 1.39 to 4.50), 2.35 (95% CI 0.58 to 9.56) and 0.98 (95% CI 0.58 to 1.68). Among women with a prior chlamydia diagnosis, the risk of SPTB did not differ between women diagnosed >1 year prior to conception, within the year prior to conception or during the pregnancy, (p=0.9). Sexually transmissible infections in pregnancy and the preconception period may be important in predicting pregnancy outcomes.
HRST architecture modeling and assessments
NASA Astrophysics Data System (ADS)
Comstock, Douglas A.
1997-01-01
This paper presents work supporting the assessment of advanced concept options for the Highly Reusable Space Transportation (HRST) study. It describes the development of computer models as the basis for creating an integrated capability to evaluate the economic feasibility and sustainability of a variety of system architectures. It summarizes modeling capabilities for use on the HRST study to perform sensitivity analysis of alternative architectures (consisting of different combinations of highly reusable vehicles, launch assist systems, and alternative operations and support concepts) in terms of cost, schedule, performance, and demand. In addition, the identification and preliminary assessment of alternative market segments for HRST applications, such as space manufacturing, space tourism, etc., is described. Finally, the development of an initial prototype model that can begin to be used for modeling alternative HRST concepts at the system level is presented.
Matthews, LT; Smit, JA; Moore, L; Milford, C; Greener, R; Mosery, FN; Ribaudo, H; Bennett, K; Crankshaw, TL; Kaida, A; Psaros, C; Safren, S; Bangsberg, DR
2015-01-01
HIV-infected men and women who choose to conceive risk infecting their partners. To inform safer conception programs we surveyed HIV risk behavior prior to recent pregnancy amongst South African, HIV-infected women (209) and men (82) recruited from antenatal and antiretroviral clinics, respectively, and reporting an uninfected or unknown-HIV-serostatus pregnancy partner. All participants knew their HIV-positive serostatus prior to the referent pregnancy. Only 11% of women and 5% of men had planned the pregnancy; 40% of women and 27% of men reported serostatus disclosure to their partner before conception. Knowledge of safer conception strategies was low. Around two-thirds reported consistent condom use, 41% of women and 88% of men reported antiretroviral therapy, and a third of women reported male partner circumcision prior to the referent pregnancy. Seven women (3%) and two men (2%) reported limiting sex without condoms to peak fertility. None reported sperm washing or manual insemination. Safer conception behaviors including HIV-serostatus disclosure, condom use, and ART at the time of conception were not associated with desired pregnancy. In light of low pregnancy planning and HIV-serostatus disclosure, interventions to improve understandings of serodiscordance and motivate mutual HIV-serostatus disclosure and pregnancy planning are necessary first steps before couples or individuals can implement specific safer conception strategies. PMID:26080688
Mayondi, Gloria K; Wirth, Kathleen; Morroni, Chelsea; Moyo, Sikhulile; Ajibola, Gbolahan; Diseko, Modiegi; Sakoi, Maureen; Magetse, Jane Dipuo; Moabi, Kebaiphe; Leidner, Jean; Makhema, Joseph; Kammerer, Betsy; Lockman, Shahin
2016-01-16
Little is known about the impact of knowledge of HIV serostatus on pregnancy intention and contraceptive use in high-HIV-burden southern African settings in the era of widespread antiretroviral treatment availability. We analyzed interview data collected among 473 HIV-uninfected and 468 HIV-infected pregnant and recently postpartum women at two sites in southern Botswana. Participants were interviewed about their knowledge of their HIV status prior to pregnancy, intendedness of the pregnancy, contraceptive use, and future childbearing desires. The median age of the 941 women was 27 years, median lifetime pregnancies was 2, and 416 (44%) of pregnancies were unintended. Among women reporting unintended pregnancy, 36% were not using a contraceptive method prior to conception. Among contraception users, 81% used condoms, 13% oral contraceptives and 5% an injectable contraceptive. In univariable analysis, women with unintended pregnancy had a higher number of previous pregnancies (P = <0.0001), were less educated (P = 0.0002), and less likely to be married or living with a partner (P < 0.0001). Thirty-percent reported knowing that they were HIV-infected, 48% reported knowing they were HIV-uninfected, and 22% reported not knowing their HIV status prior to conception. In multivariable analysis, women who did not know their HIV status pre-conception were more likely to report their pregnancy as unintended compared to women who knew that they were HIV-uninfected (aOR = 1.7; 95%CI: 1.2-2.5). After controlling for other factors, unintended pregnancy was not associated with knowing one's HIV positive status prior to conception (compared with knowing one's negative HIV status prior to conception). Among women with unintended pregnancy, there was no association between knowing their HIV status and contraceptive use prior to pregnancy in adjusted analyses. Sixty-one percent of women reported not wanting any more children after this pregnancy, with HIV-infected women significantly more likely to report not wanting any more children compared to HIV-uninfected women (aOR = 3.9; 95%CI: 2.6-5.8). The high rates of reported unintended pregnancy and contraceptive failure/misuse underscore an urgent need for better access to effective contraceptive methods for HIV-uninfected and HIV -infected women in Botswana. Lower socioeconomic status and lack of pre-conception HIV testing may indicate higher risk for unintended pregnancy in this setting.
Addressing potential prior-data conflict when using informative priors in proof-of-concept studies.
Mutsvari, Timothy; Tytgat, Dominique; Walley, Rosalind
2016-01-01
Bayesian methods are increasingly used in proof-of-concept studies. An important benefit of these methods is the potential to use informative priors, thereby reducing sample size. This is particularly relevant for treatment arms where there is a substantial amount of historical information such as placebo and active comparators. One issue with using an informative prior is the possibility of a mismatch between the informative prior and the observed data, referred to as prior-data conflict. We focus on two methods for dealing with this: a testing approach and a mixture prior approach. The testing approach assesses prior-data conflict by comparing the observed data to the prior predictive distribution and resorting to a non-informative prior if prior-data conflict is declared. The mixture prior approach uses a prior with a precise and diffuse component. We assess these approaches for the normal case via simulation and show they have some attractive features as compared with the standard one-component informative prior. For example, when the discrepancy between the prior and the data is sufficiently marked, and intuitively, one feels less certain about the results, both the testing and mixture approaches typically yield wider posterior-credible intervals than when there is no discrepancy. In contrast, when there is no discrepancy, the results of these approaches are typically similar to the standard approach. Whilst for any specific study, the operating characteristics of any selected approach should be assessed and agreed at the design stage; we believe these two approaches are each worthy of consideration. Copyright © 2015 John Wiley & Sons, Ltd.
Ernst, E
2012-01-01
The concept that alternative therapies can eliminate toxins and toxicants from the body, i.e. 'alternative detox' (AD) is popular. Selected textbooks and articles on the subject of AD. The principles of AD make no sense from a scientific perspective and there is no clinical evidence to support them. The promotion of AD treatments provides income for some entrepreneurs but has the potential to cause harm to patients and consumers. In alternative medicine, simplistic but incorrect concepts such as AD abound. AREAS TIMELY FOR RESEARCH: All therapeutic claims should be scientifically tested before being advertised-and AD cannot be an exception.
Adaptive jammer nulling in EHF communications satellites
NASA Astrophysics Data System (ADS)
Bhagwan, Jai; Kavanagh, Stephen; Yen, J. L.
A preliminary investigation is reviewed concerning adaptive null steering multibeam uplink receiving system concepts for future extremely high frequency communications satellites. Primary alternatives in the design of the uplink antenna, the multibeam adaptive nulling receiver, and the processing algorithm and optimization criterion are discussed. The alternatives are phased array, lens or reflector antennas, nulling at radio frequency or an intermediate frequency, wideband versus narrowband nulling, and various adaptive nulling algorithms. A primary determinant of the hardware complexity is the receiving system architecture, which is described for the alternative antenna and nulling concepts. The final concept chosen will be influenced by the nulling performance requirements, cost, and technological readiness.
Towards a Lakatosian Analysis of the Piagetian and Alternative Conceptions Research Programs.
ERIC Educational Resources Information Center
Gilbert, John K.; Swift, David J.
1985-01-01
Lakatos's methodology of scientific research programs is summarized and discussed for Piagetian schools and alternative conceptions movement. Commonalities/differences between these two rival programs are presented along with fundamental assumptions, auxiliary hypotheses, and research policy. Suggests that research findings should not be merely…
The Role of Prior Experience in Feedback of Beginning Teachers
ERIC Educational Resources Information Center
Blount, Tametra Danielle
2010-01-01
This causal-comparative, mixed-methods study examined the role of prior experience in the mentoring needs of first-year teachers from alternative certification programs in three Tennessee counties. Teachers examined were: teachers from traditional teacher education programs, teachers with no prior teacher education experience, teachers with prior…
ERIC Educational Resources Information Center
Sunal, Cynthia Szymanski; Karr, Charles L.; Sunal, Dennis W.
2003-01-01
Students' conceptions of three major artificial intelligence concepts used in the modeling of systems in science, fuzzy logic, neural networks, and genetic algorithms were investigated before and after a higher education science course. Students initially explored their prior ideas related to the three concepts through active tasks. Then,…
McMillan, Kim; Perron, Amélie
2013-02-01
This article aims to clarify the concept of change fatigue and deems further exploration of the concept within the discipline of nursing is relevant and necessary. The concept of change fatigue has evolved from the discipline of management as a means to explore organization change and its associated triumphs and failures. Change fatigue has typically been described as one and the same as change resistance, with very little literature acknowledging that they are in fact distinct concepts. Concept clarification has highlighted the striking differences and few similarities that exist between the concepts of change fatigue and change resistance. Further exploration and subsequent research on the concept of change fatigue is needed within the discipline of nursing. The concept not only presents new and alternative perspectives on the processes of organization change, but provides opportunity for theory development that recognizes the impact organizational change has on nurses' work lives.
Farahati, M; Bozorgi, N; Luke, B
1993-10-01
This study evaluated the influence of prior perinatal factors on birth weight, length of gestation, and maternal pregravid and postpartum weights in subsequent pregnancies. The study sample included 47 women each with first, second and third pregnancies. Mean pregravid weight increased by 5.2 lb between the first and second pregnancies and by 4.4 lb between the second and third pregnancies. Total weight gain averaged 31 lb for the first pregnancy and 28.4 and 28.3 lb for the second and third pregnancies, respectively. Mean birth weight increased by 111 g between the first and second pregnancies and by 199 g between the second and third pregnancies. Mean gestational age was similar for all three pregnancies, averaging 39.5 weeks. Using stepwise forward multiple regression analyses, we determined that birth weight and length of gestation are both influenced significantly by prior birth weight and length of gestation; subsequent pregravid weight is influenced significantly by prior rate of gain, pregravid weight and postpartum weight; and postpartum weight is significantly influenced by prior rate of gain and birth weight. Comparisons across three pregnancies for the same woman showed that differences in birth-to-conception interval were not associated with higher postpartum weight or subsequent pregravid weight. These data indicate that in healthy, nonsmoking, low-risk women, the maternal and infant outcomes of pregnancies are significantly influenced by prior outcomes but not by either short birth-to-conception interval or greater maternal age.
Barriers to College Students Learning How Rocks Form
ERIC Educational Resources Information Center
Kortz, Karen M.; Murray, Daniel P.
2009-01-01
Students do not have a good understanding of how rocks form. Instead, they have many non-scientific alternative conceptions to explain different aspects of rock formation. Using 10 interviews and nearly 200 questionnaires filled out by students at four different colleges, we identified many alternative conceptions students have about rock…
Student Conceptions of Ionic Bonding: Patterns of Thinking across Three European Contexts
ERIC Educational Resources Information Center
Taber, Keith S.; Tsaparlis, Georgios; Nakiboglu, Canan
2012-01-01
Previous research has reported that students commonly develop alternative conceptions in the core topic of chemical bonding. Research in England has reported that students there commonly demonstrate an alternative "molecular" conceptual framework for thinking about ionic bonding: in terms of the formation of molecule-like ions pairs…
ERIC Educational Resources Information Center
Piquette, Jeff S.; Heikkinen, Henry W.
2005-01-01
This study explores general-chemistry instructors' awareness of and ability to identify and address common student learning obstacles in chemical equilibrium. Reported instructor strategies directed at remediating student alternate conceptions were investigated and compared with successful, literature-based conceptual change methods. Fifty-two…
Students' Alternative Conceptions of Tropical Cyclone Causes and Processes
ERIC Educational Resources Information Center
Lane, Rod; Coutts, Pamela
2012-01-01
While Shulman argues that an important component of pedagogical content knowledge (PCK) is teachers' understanding of the alternative conceptions commonly held by students, relatively little is known about what students believe about many topics in the school curriculum. This paper focuses on a content area typically featured in Geography…
Free-piston Stirling engine conceptual design and technologies for space power, phase 1
NASA Technical Reports Server (NTRS)
Penswick, L. Barry; Beale, William T.; Wood, J. Gary
1990-01-01
As part of the SP-100 program, a phase 1 effort to design a free-piston Stirling engine (FPSE) for a space dynamic power conversion system was completed. SP-100 is a combined DOD/DOE/NASA program to develop nuclear power for space. This work was completed in the initial phases of the SP-100 program prior to the power conversion concept selection for the Ground Engineering System (GES). Stirling engine technology development as a growth option for SP-100 is continuing after this phase 1 effort. Following a review of various engine concepts, a single-cylinder engine with a linear alternator was selected for the remainder of the study. The relationships of specific mass and efficiency versus temperature ratio were determined for a power output of 25 kWe. This parametric study was done for a temperature ratio range of 1.5 to 2.0 and for hot-end temperatures of 875 K and 1075 K. A conceptual design of a 1080 K FPSE with a linear alternator producing 25 kWe output was completed. This was a single-cylinder engine designed for a 62,000 hour life and a temperature ratio of 2.0. The heat transport systems were pumped liquid-metal loops on both the hot and cold ends. These specifications were selected to match the SP-100 power system designs that were being evaluated at that time. The hot end of the engine used both refractory and superalloy materials; the hot-end pressure vessel featured an insulated design that allowed use of the superalloy material. The design was supported by the hardware demonstration of two of the component concepts - the hydrodynamic gas bearing for the displacer and the dynamic balance system. The hydrodynamic gas bearing was demonstrated on a test rig. The dynamic balance system was tested on the 1 kW RE-1000 engine at NASA Lewis.
NASA Astrophysics Data System (ADS)
Yang, Wen-Tsung; Lin, Yu-Ren; She, Hsiao-Ching; Huang, Kai-Yi
2015-07-01
This study investigated the effects of students' prior science knowledge and online learning approaches (social and individual) on their learning with regard to three topics: science concepts, inquiry, and argumentation. Two science teachers and 118 students from 4 eighth-grade science classes were invited to participate in this research. Students in each class were divided into three groups according to their level of prior science knowledge; they then took either our social- or individual-based online science learning program. The results show that students in the social online argumentation group performed better in argumentation and online argumentation learning. Qualitative analysis indicated that the students' social interactions benefited the co-construction of sound arguments and the accurate understanding of science concepts. In constructing arguments, students in the individual online argumentation group were limited to knowledge recall and self-reflection. High prior-knowledge students significantly outperformed low prior-knowledge students in all three aspects of science learning. However, the difference in inquiry and argumentation performance between low and high prior-knowledge students decreased with the progression of online learning topics.
Effects of Variation and Prior Knowledge on Abstract Concept Learning
ERIC Educational Resources Information Center
Braithwaite, David W.; Goldstone, Robert L.
2015-01-01
Learning abstract concepts through concrete examples may promote learning at the cost of inhibiting transfer. The present study investigated one approach to solving this problem: systematically varying superficial features of the examples. Participants learned to solve problems involving a mathematical concept by studying either superficially…
Conceptions of Function Composition in College Precalculus Students
ERIC Educational Resources Information Center
Bowling, Stacey
2014-01-01
Past research has shown that students have difficulty developing a robust conception of function. However, little prior research has been performed dealing with student knowledge of function composition, a potentially powerful mathematical concept. This dissertation reports the results of an investigation into student understanding and use of…
Urologists' attitudes to sexual complications of LUTS/BPH treatments.
Giona, Simone; Ganguly, Indranil; Muir, Gordon
2018-04-21
Many LUTS/BPH treatments currently available may affect sexual function (SD). We wished to assess urologists' attitude and practice in this area. Attendees of an international meeting were randomly selected, interviewed and stratified by professional status and LUTS/BPH cases seen per month. There were four questions: treatment options offered, frequency of discussing erectile dysfunction (ED) with each treatment, frequency of discussing ejaculatory dysfunction (EjD) with each treatment, and offering alternative treatment based on the risks of sexual dysfunction. 199 of the 245 interviewed (81%) were urologists. The most common treatments offered were α-blockers (99.5%), 5-ARI (95.0%) and TURP (92.5%). About 70% of the specialists discuss ED before α-blockers (not known to cause ED). Regarding EjD, 70% discuss this prior to prescribing α-blockers, 60% before 5-ARI therapy, while 80% before TURP. A significant minority fails to discuss this complication in all areas. Many respondents do not routinely discuss alternative therapies on the risk of SD. The higher the caseload, the less likely was a urologist to offer alternative therapies, with 37% of urologists seeing over 30 LUTS/BPH patients per month stating they would "Not at all often" offer alternative therapies for this reason. There is a significant discrepancy in attitudes to counselling patients on SD related to LUTS/BPH treatments. This may, in some cases, affect the validity of consent to the treatment. Most urologists do not discuss alternative treatments with patients based on the risks of different outcomes and complications, and this seems more marked in those with the busier practices. This may sit ill with the concept of personalised healthcare.
Cost/Effort Drivers and Decision Analysis
NASA Technical Reports Server (NTRS)
Seidel, Jonathan
2010-01-01
Engineering trade study analyses demand consideration of performance, cost and schedule impacts across the spectrum of alternative concepts and in direct reference to product requirements. Prior to detailed design, requirements are too often ill-defined (only goals ) and prone to creep, extending well beyond the Systems Requirements Review. Though lack of engineering design and definitive requirements inhibit the ability to perform detailed cost analyses, affordability trades still comprise the foundation of these future product decisions and must evolve in concert. This presentation excerpts results of the recent NASA subsonic Engine Concept Study for an Advanced Single Aisle Transport to demonstrate an affordability evaluation of performance characteristics and the subsequent impacts on engine architecture decisions. Applying the Process Based Economic Analysis Tool (PBEAT), development cost, production cost, as well as operation and support costs were considered in a traditional weighted ranking of the following system-level figures of merit: mission fuel burn, take-off noise, NOx emissions, and cruise speed. Weighting factors were varied to ascertain the architecture ranking sensitivities to these performance figures of merit with companion cost considerations. A more detailed examination of supersonic variable cycle engine cost is also briefly presented, with observations and recommendations for further refinements.
Simplified liquid oxygen propellant conditioning concepts
NASA Technical Reports Server (NTRS)
Cleary, N. L.; Holt, K. A.; Flachbart, R. H.
1995-01-01
Current liquid oxygen feed systems waste propellant and use hardware, unnecessary during flight, to condition the propellant at the engine turbopumps prior to launch. Simplified liquid oxygen propellant conditioning concepts are being sought for future launch vehicles. During a joint program, four alternative propellant conditioning options were studied: (1) passive recirculation; (2) low bleed through the engine; (3) recirculation lines; and (4) helium bubbling. The test configuration for this program was based on a vehicle design which used a main recirculation loop that was insulated on the downcomer and uninsulated on the upcomer. This produces a natural convection recirculation flow. The test article for this program simulated a feedline which ran from the main recirculation loop to the turbopump. The objective was to measure the temperature profile of this test article. Several parameters were varied from the baseline case to determine their effects on the temperature profile. These parameters included: flow configuration, feedline slope, heat flux, main recirculation loop velocity, pressure, bleed rate, helium bubbling, and recirculation lines. The heat flux, bleed rate, and recirculation configurations produced the greatest changes from the baseline temperature profile. However, the temperatures in the feedline remained subcooled. Any of the options studied could be used in future vehicles.
Science Education Using a Computer Model-Virtual Puget Sound
NASA Astrophysics Data System (ADS)
Fruland, R.; Winn, W.; Oppenheimer, P.; Stahr, F.; Sarason, C.
2002-12-01
We created an interactive learning environment based on an oceanographic computer model of Puget Sound-Virtual Puget Sound (VPS)-as an alternative to traditional teaching methods. Students immersed in this navigable 3-D virtual environment observed tidal movements and salinity changes, and performed tracer and buoyancy experiments. Scientific concepts were embedded in a goal-based scenario to locate a new sewage outfall in Puget Sound. Traditional science teaching methods focus on distilled representations of agreed-upon knowledge removed from real-world context and scientific debate. Our strategy leverages students' natural interest in their environment, provides meaningful context and engages students in scientific debate and knowledge creation. Results show that VPS provides a powerful learning environment, but highlights the need for research on how to most effectively represent concepts and organize interactions to support scientific inquiry and understanding. Research is also needed to ensure that new technologies and visualizations do not foster misconceptions, including the impression that the model represents reality rather than being a useful tool. In this presentation we review results from prior work with VPS and outline new work for a modeling partnership recently formed with funding from the National Ocean Partnership Program (NOPP).
Exploring Korean young children's ideas about living things
NASA Astrophysics Data System (ADS)
Kwon, Young Re
This qualitative study explored concepts of living things that five- and six-year-old Korean children held prior to formal instructional interventions and how their concepts were changed and developed over one semester in a kindergarten classroom. Six focal children in a class of 30 were interviewed in two phases and their hands-on classroom activities and teacher-children interactions were observed. The teacher's journal was also used to gather data. As the study was conducted, a number of alternative concepts related to the children's perceptions of living things were identified and described. The researcher interviewed the children to determine their initial ideas, using an informal interview guide; they responded whether certain objects were living or not, and how they told if the particular objects were living or not. The classroom activities were also observed in large/small groups and individually. An assisting observer viewed the classroom activities and simultaneously recorded science-related teacher-children interactions and the children's hands-on activities. Later the researcher made a transcription of the observer's notes. The data were also collected from the teacher's journal, in which she recorded everyday classroom activities and reflected on teaching and learning. Finally, after 8 weeks of the 16-week instructional intervention, the researcher interviewed the children, using a formal interview guide, as to how their concepts of living things had changed and developed. The researcher interviewed the children as to whether particular objects were plants or animals, neither or both, and the criteria they used to decide. The study showed that the kindergarten children had solid and unique ideas based on their everyday experience with living and non-living things prior to the formal instructional inventions. In the classroom activities, the children showed that they rejected or changed several of their own concepts of living things. The instructional interventions facilitated the children in developing scientific ideas about certain living things. Several of the children's ideas and concepts changed and corresponded to scientific viewpoints. However, others maintained their existing ideas, which were not scientifically based. The study revealed the complexity of teaching kindergarten children a scientific understanding of living things and that teaching the interconnectedness among objects was essential to elaborate concepts. The results of the research suggested improvements for the conceptual change teaching methodology used in the classroom. The study provided insight into the effects of teacher-children interactions and teaching interventions. The study also indicated that the interview and observation research methodology used in this study was a useful vehicle to explore the children's initial ideas and conceptual development in teaching and learning science. The findings of the study suggest that teacher education for teachers of young children should include a complex of instructions because teaching and learning concepts of living things and other related science concepts are complex processes.
Psychometric Analysis of the Thermochemistry Concept Inventory
ERIC Educational Resources Information Center
Wren, David; Barbera, Jack
2014-01-01
Assessing conceptual understanding of foundational topics before instruction on higher-order concepts can provide chemical educators with information to aid instructional design. This study provides an instrument that can be used to identify students' alternative conceptions regarding thermochemistry concepts. The Thermochemistry Concept Inventory…
Inferences About Sexual Orientation: The Roles of Stereotypes, Faces, and The Gaydar Myth.
Cox, William T L; Devine, Patricia G; Bischmann, Alyssa A; Hyde, Janet S
2016-01-01
In the present work, we investigated the pop cultural idea that people have a sixth sense, called "gaydar," to detect who is gay. We propose that "gaydar" is an alternate label for using stereotypes to infer orientation (e.g., inferring that fashionable men are gay). Another account, however, argues that people possess a facial perception process that enables them to identify sexual orientation from facial structure. We report five experiments testing these accounts. Participants made gay-or-straight judgments about fictional targets that were constructed using experimentally manipulated stereotypic cues and real gay/straight people's face cues. These studies revealed that orientation is not visible from the face-purportedly "face-based" gaydar arises from a third-variable confound. People do, however, readily infer orientation from stereotypic attributes (e.g., fashion, career). Furthermore, the folk concept of gaydar serves as a legitimizing myth: Compared to a control group, people stereotyped more often when led to believe in gaydar, whereas people stereotyped less when told gaydar is an alternate label for stereotyping. Discussion focuses on the implications of the gaydar myth and why, contrary to some prior claims, stereotyping is highly unlikely to result in accurate judgments about orientation.
Strategic rehabilitation planning of piped water networks using multi-criteria decision analysis.
Scholten, Lisa; Scheidegger, Andreas; Reichert, Peter; Maurer, Max; Mauer, Max; Lienert, Judit
2014-02-01
To overcome the difficulties of strategic asset management of water distribution networks, a pipe failure and a rehabilitation model are combined to predict the long-term performance of rehabilitation strategies. Bayesian parameter estimation is performed to calibrate the failure and replacement model based on a prior distribution inferred from three large water utilities in Switzerland. Multi-criteria decision analysis (MCDA) and scenario planning build the framework for evaluating 18 strategic rehabilitation alternatives under future uncertainty. Outcomes for three fundamental objectives (low costs, high reliability, and high intergenerational equity) are assessed. Exploitation of stochastic dominance concepts helps to identify twelve non-dominated alternatives and local sensitivity analysis of stakeholder preferences is used to rank them under four scenarios. Strategies with annual replacement of 1.5-2% of the network perform reasonably well under all scenarios. In contrast, the commonly used reactive replacement is not recommendable unless cost is the only relevant objective. Exemplified for a small Swiss water utility, this approach can readily be adapted to support strategic asset management for any utility size and based on objectives and preferences that matter to the respective decision makers. Copyright © 2013 Elsevier Ltd. All rights reserved.
The Influence of Teachers' Conceptions of Teaching and Learning on Their Technology Acceptance
ERIC Educational Resources Information Center
Teo, Timothy; Zhou, Mingming
2017-01-01
Prior research has attempted to incorporate different personal variables within extant theories of technology acceptance models (TAMs). This study further extends TAM by incorporating teachers' conceptions of teaching and learning (CoTL) in two forms: constructivist and traditional conceptions. The moderating effects of teachers' demographic…
Evaluation of Students' Conceptual Understanding of Malaria
NASA Astrophysics Data System (ADS)
Poh-Ai Cheong, Irene; Treagust, David; Kyeleve, Iorhemen J.; Oh, Peck-Yoke
2010-12-01
In this study, a two-tier diagnostic test for understanding malaria was developed and administered to 314 Bruneian students in Year 12 and in a nursing diploma course. The validity, reliability, difficulty level, discriminant indices, and reading ability of the test were examined and found to be acceptable in terms of measuring students' understanding and identifying alternative conceptions with respect to malaria. Results showed that students' understanding of malaria was high for content, low for reasons, and limited and superficial for both content and reasons. The instrument revealed several common alternative conceptual understandings students' hold about malaria. The MalariaTT2 instrument developed could be used in classroom lessons for challenging alternative conceptions and enhancing conceptions of malaria.
Concept Analysis of Spirituality: An Evolutionary Approach.
Weathers, Elizabeth; McCarthy, Geraldine; Coffey, Alice
2016-04-01
The aim of this article is to clarify the concept of spirituality for future nursing research. Previous concept analyses of spirituality have mostly reviewed the conceptual literature with little consideration of the empirical literature. The literature reviewed in prior concept analyses extends from 1972 to 2005, with no analysis conducted in the past 9 years. Rodgers' evolutionary framework was used to review both the theoretical and empirical literature pertaining to spirituality. Evolutionary concept analysis is a formal method of philosophical inquiry, in which papers are analyzed to identify attributes, antecedents, and consequences of the concept. Empirical and conceptual literature. Three defining attributes of spirituality were identified: connectedness, transcendence, and meaning in life. A conceptual definition of spirituality was proposed based on the findings. Also, four antecedents and five primary consequences of spirituality were identified. Spirituality is a complex concept. This concept analysis adds some clarification by proposing a definition of spirituality that is underpinned by both conceptual and empirical research. Furthermore, exemplars of spirituality, based on prior qualitative research, are presented to support the findings. Hence, the findings of this analysis could guide future nursing research on spirituality. © 2015 Wiley Periodicals, Inc.
Testing Small Variance Priors Using Prior-Posterior Predictive p Values.
Hoijtink, Herbert; van de Schoot, Rens
2017-04-03
Muthén and Asparouhov (2012) propose to evaluate model fit in structural equation models based on approximate (using small variance priors) instead of exact equality of (combinations of) parameters to zero. This is an important development that adequately addresses Cohen's (1994) The Earth is Round (p < .05), which stresses that point null-hypotheses are so precise that small and irrelevant differences from the null-hypothesis may lead to their rejection. It is tempting to evaluate small variance priors using readily available approaches like the posterior predictive p value and the DIC. However, as will be shown, both are not suited for the evaluation of models based on small variance priors. In this article, a well behaving alternative, the prior-posterior predictive p value, will be introduced. It will be shown that it is consistent, the distributions under the null and alternative hypotheses will be elaborated, and it will be applied to testing whether the difference between 2 means and the size of a correlation are relevantly different from zero. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
Alternate Approaches to Exploration: The Single Crew Module Concept
NASA Technical Reports Server (NTRS)
Chambliss, Joe
2011-01-01
The Cx Program envisioned exploration of the moon and mars using an extrapolation of the Apollo approach. If new technology development initiatives are successful, they will provide capabilities that can enable alternate approaches. This presentation will provide a brief overview of the Cx approaches for lunar and Mars missions and some of the alternatives that were considered. Then an alternative approach referred to as a Single Crew Module approach is described. The SCM concept employs new technologies in a way that could reduce exploration cost and possibly schedule. Options to the approaches will be presented and discussed.
Alternative Conceptions Concerning the Earth's Interior Exhibited by Honduran Students
ERIC Educational Resources Information Center
Capps, Daniel K.; McAllister, Meredith; Boone, William J.
2013-01-01
Although multiple studies of misconceptions in Earth science have been completed using samples of North American and European students and teachers, little research has been conducted on alternative Earth science conceptions in developing countries. The current study was conducted in 5th- and 6th-grade classrooms in eastern Honduras, Central…
Alternative Conceptions about Burning Held by Atayal Indigene Students in Taiwan
ERIC Educational Resources Information Center
Chang, Jen-Min; Lee, Huei; Yen, Chiung-Fen
2010-01-01
The purpose of this study was to investigate the alternative conceptions about burning phenomena among Atayal indigene elementary school students in Taiwan. The main difference from other relevant research is that this study assesses Atayal people's worldview by means of a questionnaire developed specifically for this purpose. There were three…
Turkish High School Students' Ideas about Invertebrates: General Characteristics and Classification
ERIC Educational Resources Information Center
Cinici, Ayhan
2013-01-01
Identifying alternative conceptions is a vital part of teaching and learning in science because it provides information about students' ideas to both themselves and their teachers. In this context, the purpose of the current study is twofold. The first aim is to examine high school students' alternative conceptions about general characteristics…
ERIC Educational Resources Information Center
Barthlow, Michelle J.; Watson, Scott B.
2014-01-01
A nonequivalent, control group design was used to investigate student achievement in secondary chemistry. This study investigated the effect of process-oriented guided inquiry learning (POGIL) in high school chemistry to reduce alternate conceptions related to the particulate nature of matter versus traditional lecture pedagogy. Data were…
ERIC Educational Resources Information Center
Hilton, Annette; Nichols, Kim
2011-01-01
Understanding bonding is fundamental to success in chemistry. A number of alternative conceptions related to chemical bonding have been reported in the literature. Research suggests that many alternative conceptions held by chemistry students result from previous teaching; if teachers are explicit in the use of representations and explain their…
Alternate Perspectives on Concept Internalization: Learning Top Down Vs. Learning Bottom Up.
ERIC Educational Resources Information Center
Pines, A. Leon
This paper outlines two alternate ways in which concepts are acquired, known as "top down" and "bottom up". "Bottom up" refers to learning the members of a category and then extracting their similarities or differences, the rule or criterial attributes used to make the categorization. In the "top down"…
NASA Astrophysics Data System (ADS)
Croft, Michael; de Berg, Kevin
2014-09-01
This paper selects six key alternative conceptions identified in the literature on student understandings of chemical bonding and illustrates how a historical analysis and a textbook analysis can inform these conceptions and lead to recommendations for improving the teaching and learning of chemical bonding at the secondary school level. The historical analysis and the textbook analysis focus on the concepts of charge, octet, electron pair, ionic, covalent and metallic bonding. Finally, a table of recommendations is made for teacher and student in the light of four fundamental questions and the six alternative conceptions to enhance the quality of the curriculum resources available and the level of student engagement.
Evolutionary space platform concept study. Volume 2, part B: Manned space platform concepts
NASA Technical Reports Server (NTRS)
1982-01-01
Logical, cost-effective steps in the evolution of manned space platforms are investigated and assessed. Tasks included the analysis of requirements for a manned space platform, identifying alternative concepts, performing system analysis and definition of the concepts, comparing the concepts and performing programmatic analysis for a reference concept.
Abraham, Joel K; Perez, Kathryn E; Price, Rebecca M
2014-01-01
Despite the impact of genetics on daily life, biology undergraduates understand some key genetics concepts poorly. One concept requiring attention is dominance, which many students understand as a fixed property of an allele or trait and regularly conflate with frequency in a population or selective advantage. We present the Dominance Concept Inventory (DCI), an instrument to gather data on selected alternative conceptions about dominance. During development of the 16-item test, we used expert surveys (n = 12), student interviews (n = 42), and field tests (n = 1763) from introductory and advanced biology undergraduates at public and private, majority- and minority-serving, 2- and 4-yr institutions in the United States. In the final field test across all subject populations (n = 709), item difficulty ranged from 0.08 to 0.84 (0.51 ± 0.049 SEM), while item discrimination ranged from 0.11 to 0.82 (0.50 ± 0.048 SEM). Internal reliability (Cronbach's alpha) was 0.77, while test-retest reliability values were 0.74 (product moment correlation) and 0.77 (intraclass correlation). The prevalence of alternative conceptions in the field tests shows that introductory and advanced students retain confusion about dominance after instruction. All measures support the DCI as a useful instrument for measuring undergraduate biology student understanding and alternative conceptions about dominance. © 2014 J. K. Abraham et al. CBE—Life Sciences Education © 2014 The American Society for Cell Biology. This article is distributed by The American Society for Cell Biology under license from the author(s). It is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).
HRST architecture modeling and assessments
DOE Office of Scientific and Technical Information (OSTI.GOV)
Comstock, D.A.
1997-01-01
This paper presents work supporting the assessment of advanced concept options for the Highly Reusable Space Transportation (HRST) study. It describes the development of computer models as the basis for creating an integrated capability to evaluate the economic feasibility and sustainability of a variety of system architectures. It summarizes modeling capabilities for use on the HRST study to perform sensitivity analysis of alternative architectures (consisting of different combinations of highly reusable vehicles, launch assist systems, and alternative operations and support concepts) in terms of cost, schedule, performance, and demand. In addition, the identification and preliminary assessment of alternative market segmentsmore » for HRST applications, such as space manufacturing, space tourism, etc., is described. Finally, the development of an initial prototype model that can begin to be used for modeling alternative HRST concepts at the system level is presented. {copyright} {ital 1997 American Institute of Physics.}« less
Design and fabrication of Ni nanowires having periodically hollow nanostructures
NASA Astrophysics Data System (ADS)
Sada, Takao; Fujigaya, Tsuyohiko; Nakashima, Naotoshi
2014-09-01
We propose a concept for the design and fabrication of metal nanowires having periodically hollow nanostructures inside the pores of an anodic aluminum oxide (AAO) membrane using a sacrificial metal. In this study, nickel (Ni) and silver (Ag) were used as the base metal and the sacrificial metal, respectively. Alternating an applied potential between -0.4 and -1.0 V provided alternatively deposited Ni and Ag segments in a Ni-Ag `barcode' nanowire with a diameter of 18 or 35 nm. After etching away the Ag segments, we fabricated Ni nanowires with nanopores of 12 +/- 5.3 nm. Such nanostructure formation is explained by the formation of a Ni shell layer over the surface of the Ag segments due to the strong affinity of Ni2+ for the interior surfaces of AAO. The Ni shell layer allows the Ni segments to remain even after dissolution of the Ag segments. Because the electroplating conditions can be easily controlled, we could carefully adjust the size and pitch of the periodically hollow nanospaces. We also describe a method for the fabrication of Ni nanorods by forming an Ag shell instead of a Ni shell on the Ni-Ag barcode nanowire, in which the interior of the AAO surfaces was modified with a compound bearing a thiol group prior to electroplating.We propose a concept for the design and fabrication of metal nanowires having periodically hollow nanostructures inside the pores of an anodic aluminum oxide (AAO) membrane using a sacrificial metal. In this study, nickel (Ni) and silver (Ag) were used as the base metal and the sacrificial metal, respectively. Alternating an applied potential between -0.4 and -1.0 V provided alternatively deposited Ni and Ag segments in a Ni-Ag `barcode' nanowire with a diameter of 18 or 35 nm. After etching away the Ag segments, we fabricated Ni nanowires with nanopores of 12 +/- 5.3 nm. Such nanostructure formation is explained by the formation of a Ni shell layer over the surface of the Ag segments due to the strong affinity of Ni2+ for the interior surfaces of AAO. The Ni shell layer allows the Ni segments to remain even after dissolution of the Ag segments. Because the electroplating conditions can be easily controlled, we could carefully adjust the size and pitch of the periodically hollow nanospaces. We also describe a method for the fabrication of Ni nanorods by forming an Ag shell instead of a Ni shell on the Ni-Ag barcode nanowire, in which the interior of the AAO surfaces was modified with a compound bearing a thiol group prior to electroplating. Electronic supplementary information (ESI) available: Information on the current profile during pulsed-electroplating, the histogram for the Ni and nanopores, and STEM images of obtained nanowires. See DOI: 10.1039/c4nr02625j
30 CFR 75.1507 - Emergency Response Plan; refuge alternatives.
Code of Federal Regulations, 2011 CFR
2011-07-01
....1507 Emergency Response Plan; refuge alternatives. (a) The Emergency Response Plan (ERP) shall include... request and the District Manager may approve an alternative location in the ERP if mining involves two... constructed prior to an event in a secure space and an isolated atmosphere, the ERP shall specify that— (1...
On the Relation between Phonotactic Learning and Alternation Learning
ERIC Educational Resources Information Center
Chong, Junxiang Adam
2017-01-01
This dissertation examines the question of how phonological alternations are learnt. In constraint-based models of phonological learning, it is hypothesized that prior learning of phonotactics from the lexicon facilitates the learning of alternations. While this is an influential assumption, the empirical evidence for it is equivocal. In this…
10 CFR 503.34 - Inability to comply with applicable environmental requirements.
Code of Federal Regulations, 2010 CFR
2010-01-01
... requirements. 503.34 Section 503.34 Energy DEPARTMENT OF ENERGY (CONTINUED) ALTERNATE FUELS NEW FACILITIES... use of alternate fuels in compliance with applicable Federal or state environmental requirements, are... presented as part of a demonstration submitted under § 503.32 (Lack of alternate fuel supply). (2) Prior to...
Code of Federal Regulations, 2010 CFR
2010-01-01
... ENERGY (CONTINUED) ALTERNATE FUELS NEW FACILITIES General Requirements for Exemptions § 503.14 Fuels search. Prior to submitting a petition for a permanent exemption for lack of alternate fuel supply, site... where OFE and the petitioner can reach accord, it may evaluate use of a different alternate fuel in lieu...
Engineering principles to assure compatible docking between future spacecraft of USA and USSR
NASA Technical Reports Server (NTRS)
Johnson, C. C.
1973-01-01
An androgynous peripheral type docking mechanism concept selected by the U.S. and the USSR is described. The rationale supporting the selection of the concept, the mechanical principles inherent to the concept, and the probable nature of future designs stemming from the concept are discussed. Operational situations prior to docking, impact conditions, energy absorption, and structural joining of two spacecraft are examined.
Mastering one's destiny: mastery goals promote challenge and success despite social identity threat.
Stout, Jane G; Dasgupta, Nilanjana
2013-06-01
We used an achievement goal framework to enhance identity-threatened individuals' motivation and performance by way of an understudied mechanism, namely, challenge appraisals. In three experiments, women were given a mastery goal (focus on building skills) or a performance goal (perform well, avoid errors) before a mock job interview. Women who focused on mastery rather than performance felt more challenged and less threatened when anticipating an identity-threatening interview; goals did not affect appraisals of a nonthreatening interview (Experiment 1). Mastery relative to performance goals enhanced women's intention to be assertive (Experiment 2) and their actual face-to-face performance during the job interview (Experiment 3); challenge appraisals (but not threat appraisals) served as a mediator for these effects. Whereas a great deal of prior work has alleviated identity threat by altering construals of one's identity, the current research uses an alternative strategy--modifying appraisals of the situation, leaving one's self-concept intact.
Ductile fracture theories for pressurised pipes and containers
NASA Technical Reports Server (NTRS)
Erdogan, F.
1976-01-01
Two mechanisms of fracture are distinguished. Plane strain fractures occur in materials which do not undergo large-scale plastic deformations prior to and during a possible fracture deformation. Plane stress or high energy fractures are generally accompanied by large inelastic deformations. Theories for analyzing plane stress are based on the concepts of critical crack opening stretch, K(R) characterization, J-integral, and plastic instability. This last is considered in some detail. The ductile fracture process involves fracture initiation followed by a stable crack growth and the onset of unstable fracture propagation. The ductile fracture propagation process may be characterized by either a multiparameter (discrete) model, or some type of a resistance curve which may be considered as a continuous model expressed graphically. These models are studied and an alternative model is also proposed for ductile fractures which cannot be modeled as progressive crack growth phenomena.
Optical, analog and digital domain architectural considerations for visual communications
NASA Astrophysics Data System (ADS)
Metz, W. A.
2008-01-01
The end of the performance entitlement historically achieved by classic scaling of CMOS devices is within sight, driven ultimately by fundamental limits. Performance entitlements predicted by classic CMOS scaling have progressively failed to be realized in recent process generations due to excessive leakage, increasing interconnect delays and scaling of gate dielectrics. Prior to reaching fundamental limits, trends in technology, architecture and economics will pressure the industry to adopt new paradigms. A likely response is to repartition system functions away from digital implementations and into new architectures. Future architectures for visual communications will require extending the implementation into the optical and analog processing domains. The fundamental properties of these domains will in turn give rise to new architectural concepts. The limits of CMOS scaling and impact on architectures will be briefly reviewed. Alternative approaches in the optical, electronic and analog domains will then be examined for advantages, architectural impact and drawbacks.
Advanced composite elevator for Boeing 727 aircraft, volume 2
NASA Technical Reports Server (NTRS)
Chovil, D. V.; Grant, W. D.; Jamison, E. S.; Syder, H.; Desper, O. E.; Harvey, S. T.; Mccarty, J. E.
1980-01-01
Preliminary design activity consisted of developing and analyzing alternate design concepts and selecting the optimum elevator configuration. This included trade studies in which durability, inspectability, producibility, repairability, and customer acceptance were evaluated. Preliminary development efforts consisted of evaluating and selecting material, identifying ancillary structural development test requirements, and defining full scale ground and flight test requirements necessary to obtain Federal Aviation Administration (FAA) certification. After selection of the optimum elevator configuration, detail design was begun and included basic configuration design improvements resulting from manufacturing verification hardware, the ancillary test program, weight analysis, and structural analysis. Detail and assembly tools were designed and fabricated to support a full-scope production program, rather than a limited run. The producibility development programs were used to verify tooling approaches, fabrication processes, and inspection methods for the production mode. Quality parts were readily fabricated and assembled with a minimum rejection rate, using prior inspection methods.
Defense on the Move: Ant-Based Cyber Defense
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fink, Glenn A.; Haack, Jereme N.; McKinnon, Archibald D.
Many common cyber defenses (like firewalls and IDS) are as static as trench warfare allowing the attacker freedom to probe them at will. The concept of Moving Target Defense (MTD) adds dynamism to the defender side, but puts the systems to be defended themselves in motion, potentially at great cost to the defender. An alternative approach is a mobile resilient defense that removes attackers’ ability to rely on prior experience without requiring motion in the protected infrastructure itself. The defensive technology absorbs most of the cost of motion, is resilient to attack, and is unpredictable to attackers. The Ant-Based Cybermore » Defense (ABCD) is a mobile resilient defense providing a set of roaming, bio-inspired, digital-ant agents working with stationary agents in a hierarchy headed by a human supervisor. The ABCD approach provides a resilient, extensible, and flexible defense that can scale to large, multi-enterprise infrastructures like the smart electric grid.« less
Fostering Radical Conceptual Change through Dual-Situated Learning Model
ERIC Educational Resources Information Center
She, Hsiao-Ching
2004-01-01
This article examines how the Dual-Situated Learning Model (DSLM) facilitates a radical change of concepts that involve the understanding of matter, process, and hierarchical attributes. The DSLM requires knowledge of students' prior beliefs of science concepts and the nature of these concepts. In addition, DSLM also serves two functions: it…
Differentiating Instruction: As Easy as One, Two, Three
ERIC Educational Resources Information Center
Shepherd, Carol; Acosta-Tello, Enid
2015-01-01
Using the "Three Phase Lesson" model, teachers identify prior knowledge that the student must possess in order to be successful in learning the new concepts. Teachers then delineate specific components inherent in the concepts that need to be mastered and identify tasks which will enable the student to practice these new concepts.
Self-Concept and Academic Achievement: A Meta-Analysis of Longitudinal Relations
ERIC Educational Resources Information Center
Huang, Chiungjung
2011-01-01
The relation between self-concept and academic achievement was examined in 39 independent and longitudinal samples through the integration of meta-analysis and path analysis procedures. For relations with more than 3 independent samples, the mean observed correlations ranged from 0.20 to 0.27 between prior self-concept and subsequent academic…
Thai Grade 10 and 11 Students' Understanding of Stoichiometry and Related Concepts
ERIC Educational Resources Information Center
Dahsah, Chanyah; Coll, Richard Kevin
2008-01-01
The research reported in this case study explores the understanding of stoichiometry and related concepts of Thai science students in grades 10 and 11 after major national curriculum reforms. Students' conceptions and alternative conceptions were investigated using a questionnaire--the "Stoichiometry Concept Questionnaire" (SCQ) (N =…
NASA Technical Reports Server (NTRS)
Rezy, B. J.; Meyers, J. E.; Tucker, J. R.; Stuckas, S. J.
1976-01-01
An analysis was conducted to screen, evaluate, and select three engine exhaust emission reduction concepts from a group of 14 candidate alternatives. A comprehensive literature search was conducted to survey the emission reduction technology state-of-the-art and establish contact with firms working on intermittent combustion engine development and pollution reduction problems. Concept development, advantages, disadvantages, and expected emission reduction responses are stated. A set of cost effectiveness criteria was developed, appraised for relative importance, and traded off against each concept so that its merit could be determined. A decision model was used to aid the evaluators in managing the criteria, making consistent judgements, calculating merit scores, and ranking the concepts. An Improved Fuel Injection System, Improved Cooling Combustion Chamber, and a Variable Timing Ignition System were recommended to NASA for approval and further concept development. An alternate concept, Air Injection, was also recommended.
Environmental Attitudes, Knowledge, and Alternative Conceptions of Primary School Children in Greece
ERIC Educational Resources Information Center
Malandrakis, Georgios; Chatzakis, Stergios
2014-01-01
In this study the environmental attitudes, knowledge, and alternative conceptions of 281 primary school children from 5th and 6th grade, ages 10-12 years were explored. Low knowledge scores, indicate a substantial lack of knowledge on basic environmental issues, while attitude scores were relatively high. Children's environmental attitudes and…
ERIC Educational Resources Information Center
Dega, Bekele Gashe; Govender, Nadaraj
2016-01-01
This study compares the scientific and alternative conceptions of energy and momentum of university first-year science students in Ethiopia and the US. Written data were collected using the Energy and Momentum Conceptual Survey developed by Singh and Rosengrant. The Concentration Analysis statistical method was used for analysing the Ethiopian…
ERIC Educational Resources Information Center
Oh, Jun-Young
2014-01-01
Constructing explanations and participating in argumentative discourse are seen as essential practices of scientific inquiry. The objective of this study was to explore the elements and origins of pre-service secondary science teachers' alternative conceptions of tidal phenomena based on the elements used in Toulmin's Argument Model through…
Students' Thinking and Alternative Conceptions of Transport Systems in Plants: A Follow-Up Study
ERIC Educational Resources Information Center
Wang, Jing-Ru
2007-01-01
The purpose of the study was to explore students' alternative conceptions and their associative thinking regarding internal transport in plants through administration of a refined diagnostic test. Questions of associative thinking and explanation were added to form a third tier of the previous two-tier test. The study found three terms related to…
ERIC Educational Resources Information Center
Ozdemir, Gokhan
2017-01-01
Students' alternative conceptions of force are one of the most studied topics, important for both science assessment and instruction. Previous studies often described students' alternative conceptions of force with a small number of well-known frameworks by utilizing interviews and paper-pencil tests in their assessments. This study aims to…
Variation in Teachers' Conceptions of Alternative Assessment in Singapore Primary Schools
ERIC Educational Resources Information Center
Tan, Kelvin H. K.
2013-01-01
Alternative assessment is an increasingly common and popular discourse in education. The potential value and benefit of alternative assessment practices are premised on significant changes in assessment practices. Many alternative assessment practices seek and promise alternatives to tests and examinations. However, labelling a practice as…
Dokoumetzidis, Aristides; Aarons, Leon
2005-08-01
We investigated the propagation of population pharmacokinetic information across clinical studies by applying Bayesian techniques. The aim was to summarize the population pharmacokinetic estimates of a study in appropriate statistical distributions in order to use them as Bayesian priors in consequent population pharmacokinetic analyses. Various data sets of simulated and real clinical data were fitted with WinBUGS, with and without informative priors. The posterior estimates of fittings with non-informative priors were used to build parametric informative priors and the whole procedure was carried on in a consecutive manner. The posterior distributions of the fittings with informative priors where compared to those of the meta-analysis fittings of the respective combinations of data sets. Good agreement was found, for the simulated and experimental datasets when the populations were exchangeable, with the posterior distribution from the fittings with the prior to be nearly identical to the ones estimated with meta-analysis. However, when populations were not exchangeble an alternative parametric form for the prior, the natural conjugate prior, had to be used in order to have consistent results. In conclusion, the results of a population pharmacokinetic analysis may be summarized in Bayesian prior distributions that can be used consecutively with other analyses. The procedure is an alternative to meta-analysis and gives comparable results. It has the advantage that it is faster than the meta-analysis, due to the large datasets used with the latter and can be performed when the data included in the prior are not actually available.
NASA Technical Reports Server (NTRS)
Samsa, M.
1980-01-01
An important effort is the Satellite Power System (SPS) comparative Assessment is the selection and characterization of alternative technologies to be compared with the SPS concept. The ground rules, criteria, and screening procedure applied in the selection of those alternative technologies are summarized. The final set of central station alternatives selected for comparison with the SPS concept includes: (1) light water reactor with improved fuel utilization, (2) conventional coal combustion with improved environmental controls, (3) open cycle gas turbine with integral low Btu gasifier, (4) terrestrial photovoltaic, (5) liquid metal fast breeder reactor, and (6) magnetic confinement fusion.
PDS4 Training: Key Concepts and Vocabulary
NASA Astrophysics Data System (ADS)
Gordon, M. K.; Guinness, E. A.; Neakrase, L. D. V.; Padams, J.; Raugh, A. C.
2017-06-01
Those planning to attend the PDS4 training session are strongly encouraged to review this poster prior to the training session. This poster briefly describes new vocabulary and a number of key concepts introduced with PDS4.
Evaluation of agile designs in first-in-human (FIH) trials--a simulation study.
Perlstein, Itay; Bolognese, James A; Krishna, Rajesh; Wagner, John A
2009-12-01
The aim of the investigation was to evaluate alternatives to standard first-in-human (FIH) designs in order to optimize the information gained from such studies by employing novel agile trial designs. Agile designs combine adaptive and flexible elements to enable optimized use of prior information either before and/or during conduct of the study to seamlessly update the study design. A comparison of the traditional 6 + 2 (active + placebo) subjects per cohort design with alternative, reduced sample size, agile designs was performed by using discrete event simulation. Agile designs were evaluated for specific adverse event models and rates as well as dose-proportional, saturated, and steep-accumulation pharmacokinetic profiles. Alternative, reduced sample size (hereafter referred to as agile) designs are proposed for cases where prior knowledge about pharmacokinetics and/or adverse event relationships are available or appropriately assumed. Additionally, preferred alternatives are proposed for a general case when prior knowledge is limited or unavailable. Within the tested conditions and stated assumptions, some agile designs were found to be as efficient as traditional designs. Thus, simulations demonstrated that the agile design is a robust and feasible approach to FIH clinical trials, with no meaningful loss of relevant information, as it relates to PK and AE assumptions. In some circumstances, applying agile designs may decrease the duration and resources required for Phase I studies, increasing the efficiency of early clinical development. We highlight the value and importance of useful prior information when specifying key assumptions related to safety, tolerability, and PK.
NASA Astrophysics Data System (ADS)
Reuter, Jewel Jurovich
The purpose of this exploratory research was to study how students learn photosynthesis and cellular respiration and to determine the value added to the student's learning by each of the three technology-scaffolded learning strategy components (animated concept presentations and WebQuest-style activities, data collection, and student-constructed animations) of the BioDatamation(TM) (BDM) Program. BDM learning strategies utilized the Theory of Interacting Visual Fields(TM) (TIVF) (Reuter & Wandersee, 2002a, 2002b; 2003a, 2003b) which holds that meaningful knowledge is hierarchically constructed using the past, present, and future visual fields, with visual metacognitive components that are derived from the principles of Visual Behavior (Jones, 1995), Human Constructivist Theory (Mintzes & Wandersee, 1998a), and Visual Information Design Theory (Tufte, 1990, 1997, 2001). Student alternative conceptions of photosynthesis and cellular respiration were determined by the item analysis of 263,267 Biology Advanced Placement Examinations and were used to develop the BDM instructional strategy and interview questions. The subjects were 24 undergraduate students of high and low biology prior knowledge enrolled in an introductory-level General Biology course at a major research university in the Deep South. Fifteen participants received BDM instruction which included original and innovative learning materials and laboratories in 6 phases; 8 of the 15 participants were the subject of in depth, extended individual analysis. The other 9 participants received traditional, non-BDM instruction. Interviews which included participants' creation of concept maps and visual field diagrams were conducted after each phase. Various content analyses, including Chi's Verbal Analysis and quantitizing/qualitizing were used for data analysis. The total value added to integrative knowledge during BDM instruction with the three visual fields was an average increase of 56% for cellular respiration and 62% increase for photosynthesis knowledge, improved long-term memory of concepts, and enhanced biological literacy to the multidimensional level, as determined by the BSCS literacy model. WebQuest-style activities and data collection provided for animated prior knowledge in the past visual field, and detailed content knowledge construction in the present visual field. During student construction of animated presentations, layering required participants to think by rearranging words and images for improved hierarchical organization of knowledge with real-life applications.
Bayesian Phase II optimization for time-to-event data based on historical information.
Bertsche, Anja; Fleischer, Frank; Beyersmann, Jan; Nehmiz, Gerhard
2017-01-01
After exploratory drug development, companies face the decision whether to initiate confirmatory trials based on limited efficacy information. This proof-of-concept decision is typically performed after a Phase II trial studying a novel treatment versus either placebo or an active comparator. The article aims to optimize the design of such a proof-of-concept trial with respect to decision making. We incorporate historical information and develop pre-specified decision criteria accounting for the uncertainty of the observed treatment effect. We optimize these criteria based on sensitivity and specificity, given the historical information. Specifically, time-to-event data are considered in a randomized 2-arm trial with additional prior information on the control treatment. The proof-of-concept criterion uses treatment effect size, rather than significance. Criteria are defined on the posterior distribution of the hazard ratio given the Phase II data and the historical control information. Event times are exponentially modeled within groups, allowing for group-specific conjugate prior-to-posterior calculation. While a non-informative prior is placed on the investigational treatment, the control prior is constructed via the meta-analytic-predictive approach. The design parameters including sample size and allocation ratio are then optimized, maximizing the probability of taking the right decision. The approach is illustrated with an example in lung cancer.
Nonlinear Development and Secondary Instability of Traveling Crossflow Vortices
NASA Technical Reports Server (NTRS)
Li, Fei; Choudhari, Meelan M.; Duan, Lian; Chang, Chau-Lyan
2014-01-01
Transition research under NASA's Aeronautical Sciences Project seeks to develop a validated set of variable fidelity prediction tools with known strengths and limitations, so as to enable "sufficiently" accurate transition prediction and practical transition control for future vehicle concepts. This paper builds upon prior effort targeting the laminar breakdown mechanisms associated with stationary crossflow instability over a swept-wing configuration relevant to subsonic aircraft with laminar flow technology. Specifically, transition via secondary instability of traveling crossflow modes is investigated as an alternate scenario for transition. Results show that, for the parameter range investigated herein, secondary instability of traveling crossflow modes becomes insignificant in relation to the secondary instability of the stationary modes when the relative initial amplitudes of the traveling crossflow instability are lower than those of the stationary modes by approximately two orders of magnitudes or more. Linear growth predictions based on the secondary instability theory are found to agree well with those based on PSE and DNS, with the most significant discrepancies being limited to spatial regions of relatively weak secondary growth, i.e., regions where the primary disturbance amplitudes are smaller in comparison to its peak amplitude. Nonlinear effects on secondary instability evolution is also investigated and found to be initially stabilizing, prior to breakdown.
75 FR 7047 - FTA Fiscal Year 2010 Apportionments, Allocations, and Program Information
Federal Register 2010, 2011, 2012, 2013, 2014
2010-02-16
... Transit in Parks Program (49 U.S.C. 5320) P. Alternatives Analysis Program (49 U.S.C. 5339) Q. Growing... Section 5317 New Freedom Apportionments 19. FTA FY 2010 Section 5339 Alternatives Analysis Allocations 20. FTA Prior Year Unobligated Section 5339 Alternatives Analysis Allocations Appendix I. Overview FTA's...
40 CFR 75.66 - Petitions to the Administrator.
Code of Federal Regulations, 2010 CFR
2010-07-01
... for alternative method of accounting for emissions prior to completion of certification tests. The... for an alternative to the stabilization criteria for the cycle time test in section 6.4 of appendix A... Administrator to use an alternative stabilization criteria for the cycle time test in section 6.4 of appendix A...
Determining the Exchangeability of Concept Map and Problem-Solving Essay Scores
ERIC Educational Resources Information Center
Hollenbeck, Keith; Twyman, Todd; Tindal, Gerald
2006-01-01
This study investigated the score exchangeability of concept maps with problem-solving essays. Of interest was whether sixth-grade students' concept maps predicted their scores on essay responses that used concept map content. Concept maps were hypothesized to be alternatives to performance assessments for content-area domain knowledge in science.…
Klafke, Nadja; Mahler, Cornelia; von Hagens, Cornelia; Blaser, Gisela; Bentner, Martina; Joos, Stefanie
2016-05-01
The purpose of this study was to develop a complex nursing intervention including complementary and alternative medicine (CAM) for breast and gynecologic cancer patients during chemotherapy to improve quality of life. Data sources Theoretical framework and concepts, practical nursing knowledge, and evidence-based studies were compiled in interprofessional meetings. Data synthesis The final complex intervention consists of three autonomous, but interacting components: (1) CAM nursing package, (2) resource-oriented counseling, and (3) evidence-based information material on CAM. CAM interventions include acupressure, aromatherapy, compress, and massage, targeting 14 clinically relevant symptoms during chemotherapy. Participants receive these interventions during chemotherapy with instructions for self care. During a counseling interview, the patient's needs and preferences are assessed by trained nurses. Furthermore, participants are equipped with evidence-based information material (booklet and DVD). Prior to study start, nurses attended training modules for administering CAM therapies and for communicating and counseling within the salutogenic approach. It was possible to design a multimodal CAM nursing intervention based on a theoretical concept, evidence-based studies, and practical nursing experience targeting the prevention or relief of side-effects women suffer during chemotherapy. The systematic analysis of the CONGO study will contribute to evidence-based CAM nursing care within supportive cancer care. Oncology nurses play an important role in supportive CAM care of breast and gynecologic cancer patients in daily clinical practice. Within oncology outpatient services, the implementation of evidence-based CAM nursing interventions and counseling may contribute to understand the impact of nursing on patient quality of life and symptom relief. This can lead to a new understanding of the nurse's professional role.
ERIC Educational Resources Information Center
Marchand, C.; d'Ivernois, J. F.; Assal, J. P.; Slama, G.; Hivon, R.
2002-01-01
Assesses whether concept maps used with diabetic patients could describe their cognitive structure, before and after having followed an educational program. Involves 10 diabetic patients and shows that concept maps can be a suitable technique to explore the type and organization of the patients' prior knowledge and to visualize what they have…
Civic Duty: Young People's Conceptions of Voting as a Means of Political Participation
ERIC Educational Resources Information Center
Chakera, Ottilia; Sears, Alan
2006-01-01
Many citizens have disengaged from participation in civic life with a resulting call for new initiatives in civic education. Many of these programs have had little research on citizens' prior conceptions of participation. In this article, we provide a map of the conceptions of civic participation, specifically voting, held by two groups: recent…
ERIC Educational Resources Information Center
Caleon, Imelda; Subramaniam, R.
2013-01-01
The effectiveness of a refutational text in addressing the alternative conceptions held by secondary school students on the topic of wave propagation in an elastic medium was explored in this study. The refutational text, which was 816 words long and featured the particle-spring model, was found to be more effective in promoting conceptual change…
Advanced Civilian Aeronautical Concepts
NASA Technical Reports Server (NTRS)
Bushnell, Dennis M.
1996-01-01
Paper discusses alternatives to currently deployed systems which could provide revolutionary improvements in metrics applicable to civilian aeronautics. Specific missions addressed include subsonic transports, supersonic transports and personal aircraft. These alternative systems and concepts are enabled by recent and envisaged advancements in electronics, communications, computing and Designer Fluid Mechanics in conjunction with a design approach employing extensive synergistic interactions between propulsion, aerodynamics and structures.
ERIC Educational Resources Information Center
Bayrak, Beyza Karadeniz
2013-01-01
The purpose of this study was to identify primary students' conceptual understanding and alternative conceptions in acid-base. For this reason, a 15 items two-tier multiple choice test administered 56 eighth grade students in spring semester 2009-2010. Data for this study were collected using a conceptual understanding scale prepared to include…
ERIC Educational Resources Information Center
Ozmen, Haluk
2007-01-01
This study investigated the effectiveness of conceptual change texts in remediating high school students' alternative conceptions concerning chemical equilibrium. A quasi-experimental design was used in this study. The subjects for this study consisted of a total 78 tenth-grade students, 38 of them in the experimental group and 40 of them in the…
ERIC Educational Resources Information Center
Sabanci, Osman; Kurnaz, Sefika; Yürük, Nejla
2016-01-01
Many studies have shown that students at different age levels come into classrooms with a variety of alternative conceptions. Commonly held alternative conceptions are the main source of the difficulties that students and teachers face in learning and teaching. The aim of this study was to compare the conceptual understanding of students who were…
ERIC Educational Resources Information Center
Potgieter, Marietjie; Malatje, Esther; Gaigher, Estelle; Venter, Elsie
2010-01-01
This study investigated the use of performance-confidence relationships to signal the presence of alternative conceptions and inadequate problem-solving skills in mechanics. A group of 33 students entering physics at a South African university participated in the project. The test instrument consisted of 20 items derived from existing standardised…
Introducing linear functions: an alternative statistical approach
NASA Astrophysics Data System (ADS)
Nolan, Caroline; Herbert, Sandra
2015-12-01
The introduction of linear functions is the turning point where many students decide if mathematics is useful or not. This means the role of parameters and variables in linear functions could be considered to be `threshold concepts'. There is recognition that linear functions can be taught in context through the exploration of linear modelling examples, but this has its limitations. Currently, statistical data is easily attainable, and graphics or computer algebra system (CAS) calculators are common in many classrooms. The use of this technology provides ease of access to different representations of linear functions as well as the ability to fit a least-squares line for real-life data. This means these calculators could support a possible alternative approach to the introduction of linear functions. This study compares the results of an end-of-topic test for two classes of Australian middle secondary students at a regional school to determine if such an alternative approach is feasible. In this study, test questions were grouped by concept and subjected to concept by concept analysis of the means of test results of the two classes. This analysis revealed that the students following the alternative approach demonstrated greater competence with non-standard questions.
Design of stabilized platforms for deep space optical communications (DSOC)
NASA Astrophysics Data System (ADS)
Jacka, N.; Walter, R.; Laughlin, D.; McNally, J.
2017-02-01
Numerous Deep Space Optical Communications (DSOC) demonstrations are planned by NASA to provide the basis for future implementation of optical communications links in planetary science missions and eventually manned missions to Mars. There is a need for a simple, robust precision optical stabilization concept for long-range free space optical communications applications suitable for optical apertures and masses larger than the current state of the art. We developed a stabilization concept by exploiting the ultra-low noise and wide bandwidth of ATA-proprietary Magnetohydrodynamic (MHD) angular rate sensors and building on prior practices of flexure-based isolation. We detail a stabilization approach tailored for deep space optical communications, and present an innovative prototype design and test results. Our prototype system provides sub-micro radian stabilization for a deep space optical link such as NASA's integrated Radio frequency and Optical Communications (iROC) and NASA's DSOC programs. Initial test results and simulations suggest that >40 dB broadband jitter rejection is possible without placing unrealistic expectations on the control loop bandwidth and flexure isolation frequency. This approach offers a simple, robust method for platform stabilization without requiring a gravity offload apparatus for ground testing or launch locks to survive a typical launch environment. This paper reviews alternative stabilization concepts, their advantages and disadvantages, as well as, their applicability to various optical communications applications. We present results from testing that subjected the prototype system to realistic spacecraft base motion and confirmed predicted sub-micro radian stabilization performance with a realistic 20-cm aperture.
Students' integration of multiple representations in a titration experiment
NASA Astrophysics Data System (ADS)
Kunze, Nicole M.
A complete understanding of a chemical concept is dependent upon a student's ability to understand the microscopic or particulate nature of the phenomenon and integrate the microscopic, symbolic, and macroscopic representations of the phenomenon. Acid-base chemistry is a general chemistry topic requiring students to understand the topics of chemical reactions, solutions, and equilibrium presented earlier in the course. In this study, twenty-five student volunteers from a second semester general chemistry course completed two interviews. The first interview was completed prior to any classroom instruction on acids and bases. The second interview took place after classroom instruction, a prelab activity consisting of a titration calculation worksheet, a titration computer simulation, or a microscopic level animation of a titration, and two microcomputer-based laboratory (MBL) titration experiments. During the interviews, participants were asked to define and describe acid-base concepts and in the second interview they also drew the microscopic representations of four stages in an acid-base titration. An analysis of the data showed that participants had integrated the three representations of an acid-base titration to varying degrees. While some participants showed complete understanding of acids, bases, titrations, and solution chemistry, other participants showed several alternative conceptions concerning strong acid and base dissociation, the formation of titration products, and the dissociation of soluble salts. Before instruction, participants' definitions of acid, base, and pH were brief and consisted of descriptive terms. After instruction, the definitions were more scientific and reflected the definitions presented during classroom instruction.
The Role of Alternative Programming in College Radio.
ERIC Educational Resources Information Center
Sauls, Samuel J.
College radio is quite often viewed as the true alternative to commercial radio. However, what is alternative radio and how does college radio factor into the ideal? To further understand this concept, this paper focuses on the role of alternative programming in college radio. Areas discussed include alternative radio as a non-mainstream form of…
Paul Hill d/b/a Alternative Energy Windows and Siding
Paul Hill d/b/a Alternative Energy Windows and Siding (the Company) is located in Concord, New Hampshire. The settlement involves renovation activities conducted at property constructed prior to 1978, located in Concord, New Hampshire.
ERIC Educational Resources Information Center
Stenlund, Tova
2012-01-01
Assessment of Prior Learning (APL) refers to a process where adults' prior learning, formal as well as informal, is assessed and acknowledged. In the first section of this paper, APL and current conceptions of validity in assessments and its evaluation are presented. It is argued that participants in the assessment are an important source of…
Investigating Elementary Teachers' Conceptions of Animal Classification
ERIC Educational Resources Information Center
Burgoon, Jacob N.; Duran, Emilio
2012-01-01
Numerous studies have been conducted regarding alternative conceptions about animal diversity and classification, many of which have used a cross-age approach to investigate how students' conceptions change over time. None of these studies, however, have investigated teachers' conceptions of animal classification. This study was intended to…
Alternative divertor target concepts for next step fusion devices
NASA Astrophysics Data System (ADS)
Mazul, I. V.
2016-12-01
The operational conditions of a divertor target in the next steps of fusion devices are more severe in comparison with ITER. The current divertor designs and technologies have a limited application concerning these conditions, and so new design concepts/technologies are required. The main reasons which practically prevent the use of the traditional motionless solid divertor target are analyzed. We describe several alternative divertor target concepts in this paper. The comparative analysis of these concepts (including the advantages and the drawbacks) is made and the prospects for their practical implementation are prioritized. The concept of the swept divertor target with a liquid metal interlayer between the moving armour and motionless heat-sink is presented in more detail. The critical issues of this design are listed and outlined, and the possible experiments are presented.
NASA Astrophysics Data System (ADS)
Svedholm, Annika M.; Lindeman, Marjaana
2013-03-01
Lay conceptions of energy often conflict with scientific knowledge, hinder science learning and scientific literacy, and provide a basis for ungrounded beliefs. In a sample of Finnish upper secondary school students, energy was attributed with features of living and animate beings and thought of as a mental property. These ontologically confused conceptions (OCC) were associated with trust in complementary and alternative medicine (CAM), and independent of scientifically valid conceptions. Substance-based energy conceptions followed the correlational pattern of OCC, rather than scientific conceptions. OCC and CAM decreased both during the regular school physics curriculum and after a lesson targeted at the ontological confusions. OCC and CAM were slightly less common among students with high actively open-minded thinking, low trust in intuition and high need for cognition. The findings are discussed in relation to the goals of scientific education.
Children's Working Theories: Invoking Disequilibrium
ERIC Educational Resources Information Center
Lovatt, Daniel; Hedges, Helen
2015-01-01
One of the outcomes of the New Zealand early childhood curriculum, "Te Whariki", is "working theories". Prior research on this concept has primarily utilised sociocultural theoretical underpinnings and neglected Piagetian constructivist theories. This paper explores ways the Piagetian concepts of equilibrium and disequilibrium…
NASA Astrophysics Data System (ADS)
Griffard, Phyllis Baudoin
1999-11-01
The main research question of this study was: What gaps in biochemical understanding are revealed by a range of university introductory biology students as they work through a critically acclaimed multimedia program on photosynthesis, and what are the corresponding implications for elaboration of the Ausubel-Novak-Gowin Learning Theory (ANG, now Human Constructivism)? Twelve students, mixed for ability, gender and ethnicity, were recruited from two sections of "Bio 101." Before and after instruction in photosynthesis, in-depth clinical interviews were conducted during which participants completed a range of cognitive tasks such as sorting, concept mapping, explaining and predicting. Some tasks involved interacting with a computer simulation of photosynthesis. This study primarily employed qualitative case study and verbal analysis methods. Verbal analysis of the clinical interviews revealed numerous gaps that were categorized into typologies. The two major categories were propositional gaps and processing gaps. Propositional gaps were evident in development of participants' concepts, links and constructs. Significant among these were conceptual distance gaps and continuity of matter gaps. Gaps such as convention gaps and relative significance gaps seem to be due to naivete in the discipline. Processing gaps included gaps in graphic decoding skills and relevant cognitive habits such as self-monitoring and consulting prior knowledge. Although the gaps were easier to detect and isolate with the above-average participants, all participants showed evidence of at least some of these gaps. Since some gaps are not unexpected at all but the highest literacy levels, not all the gaps identified are to be considered deficiencies. The gaps identified support the attention given by ANG theorists to the role of prior knowledge and metacognition as well as the value of graphic organizers in knowledge construction. In addition, this study revealed numerous gaps in graphic decoding, indicating that both direct experience and explicit instruction are needed if students are to "learn how to learn with graphics," especially those graphics central to understanding a computer simulation's representations of structures, inputs, processes and outputs. It is hypothesized that gaps similar to those revealed in this study may be at the root of some alternative conceptions documented in the literature.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 16 2011-07-01 2011-07-01 false What alternative sulfur standards and... ADDITIVES Gasoline Sulfur Gasoline Sulfur Standards § 80.213 What alternative sulfur standards and... TGP meets the applicable sulfur standards under § 80.210 or § 80.220, prior to the TGP leaving the...
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 16 2010-07-01 2010-07-01 false What alternative sulfur standards and... ADDITIVES Gasoline Sulfur Gasoline Sulfur Standards § 80.213 What alternative sulfur standards and... TGP meets the applicable sulfur standards under § 80.210 or § 80.220, prior to the TGP leaving the...
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 17 2014-07-01 2014-07-01 false What alternative sulfur standards and... ADDITIVES Gasoline Sulfur Gasoline Sulfur Standards § 80.213 What alternative sulfur standards and... TGP meets the applicable sulfur standards under § 80.210 or § 80.220, prior to the TGP leaving the...
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 17 2013-07-01 2013-07-01 false What alternative sulfur standards and... ADDITIVES Gasoline Sulfur Gasoline Sulfur Standards § 80.213 What alternative sulfur standards and... TGP meets the applicable sulfur standards under § 80.210 or § 80.220, prior to the TGP leaving the...
ERIC Educational Resources Information Center
Hoe, Kai Yee; Subramaniam, R.
2016-01-01
This study presents an analysis of alternative conceptions (ACs) on acid--base chemistry harbored by grade 9 students in Singapore. The ACs were obtained by the development and validation of a 4-tier diagnostic instrument. It is among the very few studies in the science education literature that have focused on examining results based also on…
ERIC Educational Resources Information Center
Chang, Chew-Hung; Pascua, Liberty
2015-01-01
This study identified secondary school students' alternative conceptions (ACs) of climate change and their resistance to instruction. Using a case-based approach, a diagnostic test was administered to Secondary 3 male students in a pre-test and post-test. The ACs identified in the pre-test were on the causes of climate change, the natural…
ERIC Educational Resources Information Center
Abdullah, Nurdiana; Surif, Johari
2015-01-01
This study is conducted with the purpose of identifying the alternative framework contained in students' imagination on the concept of matter at submicroscopic level. Through the design of purposive sampling techniques, a total of 15 students are interviewed to obtain the data. Data from analysis document is utilized to strengthen the interview.…
Concept design and alternate arrangements of orbiter mid-deck habitability features
NASA Technical Reports Server (NTRS)
Church, R. A.; Ciciora, J. A.; Porter, K. L.; Stevenson, G. E.
1976-01-01
The evaluations and recommendations for habitability features in the space shuttle orbiter mid-deck are summarized. The orbiter mission plans, the mid-deck dimensions and baseline arrangements along with crew compliments and typical activities were defined. Female and male anthropometric data based on zero-g operations were also defined. Evaluations of baseline and alternate feasible concepts provided several recommendations which are discussed.
ERIC Educational Resources Information Center
Yan, Yaw Kai; Subramaniam, R.
2018-01-01
This study focused on grade 12 students' understanding of reaction kinetics. A 4-tier diagnostic instrument was developed for this purpose and administered to 137 students in the main study. Findings showed that reaction kinetics is a difficult topic for these students, with a total of 25 alternative conceptions (ACs) being uncovered. Except for…
Artist's concept of Hadley-Apennine landing site with alternate traverses
1971-06-01
S71-33432 (1 July 1971) --- These alternative traverses can be carried out on foot. They will be used if the Lunar Roving Vehicle (LRV) becomes inoperative. This artist's concept showing part of the Hadley Rille and several of the Apennine Mountains was excerpted from "On the Moon with Apollo 15: A Guidebook to the Hadley-Apennine Region," by Gene Simmons. Artwork by Jerry Elmore.
Alternative conceptions, memory, & mental models in physics education
NASA Astrophysics Data System (ADS)
Lee, Gyoungho; Shin, Jongho; Park, Jiyeon; Song, Sangho; Kim, Yeounsoo; Bao, Lei
2005-09-01
There are two somewhat independent research traditions, which converge to suggest a form of students' knowledge: alternative conceptions and mental models. However we have little literature that explains what they are different from each other and from memory. This study tried to describe these issues with some thoughts about how cognitive psychology and science education approaches can be best synthesized in order to approach these questions.
The Impact of Concept Mapping on the Process of Problem-Based Learning
ERIC Educational Resources Information Center
Zwaal, Wichard; Otting, Hans
2012-01-01
A concept map is a graphical tool to activate and elaborate on prior knowledge, to support problem solving, promote conceptual thinking and understanding, and to organize and memorize knowledge. The aim of this study is to determine if the use of concept mapping (CM) in a problem-based learning (PBL) curriculum enhances the PBL process. The paper…
ERIC Educational Resources Information Center
Marsh, Herbert W.; Gerlach, Erin; Trautwein, Ulrich; Ludtke, Oliver; Brettschneider, Wolf-Dietrich
2007-01-01
Do preadolescent sport self-concepts influence subsequent sport performance? Longitudinal data (Grades 3, 4, and 6) for young boys and girls (N = 1,135; mean age = 9.67) were used to test reciprocal effects model (REM) predictions that sport self-concept is both a cause and a consequence of sport accomplishments. Controlling prior sport…
Marsh, Herbert W; Chanal, Julien P; Sarrazin, Philippe G
2006-01-01
A large body of research in support of the reciprocal effects model of causal ordering demonstrates that prior academic self-concept predicts subsequent academic achievement beyond what can be explained in terms of prior achievement. Here we evaluate the generalizability of this support for the reciprocal effects model to a physical activity context in which achievement is reflected in gymnastics skills on a standardized gymnastics performance test evaluated by expert judges. Based on the responses of 376 adolescents collected at the start (T1) and end (T2) of a gymnastics training programme, there is support for a reciprocal effects model in which there are significant paths leading from both T1 gymnastics self-concept to T2 gymnastics skills and from T1 gymnastics skills to T2 self-concept. Although there were gender and age effects (girls and older participants had better gymnastics skills, boys had higher self-concepts), multiple group structural equation models indicated that support for the reciprocal effects model generalized over responses by boys and girls. In summary, self-concept and performance are both determinants and consequences of each other.
Numerical Modeling of the 2014 Oso, Washington, Landslide.
NASA Astrophysics Data System (ADS)
George, D. L.; Iverson, R. M.
2014-12-01
Numerical simulations of alternative scenarios that could have transpired during the Oso, Washington, landslide of 22 March 2014 provide insight into factors responsible for the landslide's devastating high-speed runout.We performed these simulations using D-Claw, a numerical model we recently developed to simulate landslide and debris-flow motion from initiation to deposition. D-Claw solves a hyperbolic system of five partial differential equations that describe simultaneous evolution of the thickness,solid volume fraction, basal pore-fluid pressure, and two components of momentum of the moving mass. D-Claw embodies the concept ofstate-dependent dilatancy, which causes the solid volume fraction m to evolve toward a value that is equilibrated to the ambient stress state andshear rate. As the value of m evolves, basal pore-fluid pressure coevolves,and thereby causes an evolution in frictional resistance to motion. Our Oso simulations considered alternative scenarios in which values of all model parameters except the initial solid volume fraction m0 were held constant.These values were: basal friction angle = 36°; static critical-state solidvolume fraction = 0.64; initial sediment permeability = 10-8 m2; pore-fluid density = 1100 kg/m3; sediment grain density = 2700 kg/m3; pore-fluid viscosity = 0.005 Pa-s; and dimensionless sediment compressibility coefficient = 0.03. Simulations performed using these values and m0 = 0.62 produced widespread landslide liquefaction, runaway acceleration, andlandslide runout distances, patterns and speeds similar to those observed or inferred for the devastating Oso event. Alternative simulations that usedm0 = 0.64 produced a much slower landslide that did not liquefy and that traveled only about 100 m before stopping. This relatively benign behavioris similar to that of several landslides at the Oso site prior to 2014. Our findings illustrate a behavioral bifurcation that is highly sensitive to the initial solid volume fraction. They suggest that the destructiveness of the2014 Oso event may have resulted in part from prior slope deformation that produced a dilated sediment state that made the sediment susceptible to contraction and liquefaction as it began to fail on March 22.
It's Time for a Conceptual Change.
ERIC Educational Resources Information Center
Hausfather, Samuel J.
1992-01-01
Conceptual change teaching is an instructional method that helps students modify, extend, or exchange their alternative conceptions for the appropriate scientific conceptions. Provides activities and a diagnostic test to apply the method to the concepts of heat and temperature. (MDH)
The place of reconstructive tubal surgery in the era of assisted reproductive techniques.
Gomel, Victor
2015-12-01
Assisted reproductive techniques yield high rates of success for women with tubal factor infertility. Because they are potentially effective for all categories of infertility, for two decades, clinical and basic research in infertility has been focused on IVF techniques and outcomes, rather than developing surgical techniques or training infertility subspecialists in tubal microsurgery. Nonetheless, in comparison with IVF, reconstructive tubal surgery is inexpensive and offers multiple opportunities to attempt conception. Performing laparoscopic salpingostomy prior to IVF in women with good prognosis tubal disease may improve the outcome of subsequent IVF, while offering the potential for spontaneous conception. Tubo-tubal anastomosis for reversal of tubal ligation, performed either by a microsurgical technique through a mini-laparotomy or by laparoscopy, is preferable to IVF in younger women with no other fertility factors, because it offers potentially higher cumulative pregnancy rates. Surgery is the only alternative for women with tubal factor infertility who for personal or other reasons are unable to undergo assisted reproductive techniques. Tubal reconstructive surgery and assisted reproductive techniques must be considered complementary forms of treatment for women with tubal factor infertility, and training in tubal reconstructive surgery should be an integral part of subspecialty training in reproductive endocrinology and infertility. Copyright © 2015 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.
Design and fabrication of Ni nanowires having periodically hollow nanostructures.
Sada, Takao; Fujigaya, Tsuyohiko; Nakashima, Naotoshi
2014-10-07
We propose a concept for the design and fabrication of metal nanowires having periodically hollow nanostructures inside the pores of an anodic aluminum oxide (AAO) membrane using a sacrificial metal. In this study, nickel (Ni) and silver (Ag) were used as the base metal and the sacrificial metal, respectively. Alternating an applied potential between -0.4 and -1.0 V provided alternatively deposited Ni and Ag segments in a Ni-Ag 'barcode' nanowire with a diameter of 18 or 35 nm. After etching away the Ag segments, we fabricated Ni nanowires with nanopores of 12 ± 5.3 nm. Such nanostructure formation is explained by the formation of a Ni shell layer over the surface of the Ag segments due to the strong affinity of Ni(2+) for the interior surfaces of AAO. The Ni shell layer allows the Ni segments to remain even after dissolution of the Ag segments. Because the electroplating conditions can be easily controlled, we could carefully adjust the size and pitch of the periodically hollow nanospaces. We also describe a method for the fabrication of Ni nanorods by forming an Ag shell instead of a Ni shell on the Ni-Ag barcode nanowire, in which the interior of the AAO surfaces was modified with a compound bearing a thiol group prior to electroplating.
GN and C Design Overview and Flight Test Results from NASA's Max Launch Abort System (MLAS)
NASA Technical Reports Server (NTRS)
Dennehy, Cornelius J.; Lanzi, Ryamond J.; Ward, Philip R.
2010-01-01
The National Aeronautics and Space Administration (NASA) Engineering and Safety Center (NESC) designed, developed and flew the alternative Max Launch Abort System (MLAS) as risk mitigation for the baseline Orion spacecraft launch abort system (LAS) already in development. The NESC was tasked with both formulating a conceptual objective system (OS) design of this alternative MLAS as well as demonstrating this concept with a simulated pad abort flight test. The goal was to obtain sufficient flight test data to assess performance, validate models/tools, and to reduce the design and development risks for a MLAS OS. Less than 2 years after Project start the MLAS simulated pad abort flight test was successfully conducted from Wallops Island on July 8, 2009. The entire flight test duration was 88 seconds during which time multiple staging events were performed and nine separate critically timed parachute deployments occurred as scheduled. Overall, the as-flown flight performance was as predicted prior to launch. This paper provides an overview of the guidance navigation and control (GN&C) technical approaches employed on this rapid prototyping activity. This paper describes the methodology used to design the MLAS flight test vehicle (FTV). Lessons that were learned during this rapid prototyping project are also summarized.
Inferences About Sexual Orientation: The Role of Stereotypes, Faces, and The Gaydar Myth
Cox, William T. L.; Devine, Patricia G.; Bischmann, Alyssa A.; Hyde, Janet S.
2015-01-01
In the present work, we investigate the pop cultural idea that people have a sixth sense, called “gaydar,” to detect who is gay. We propose that “gaydar” is an alternate label for using stereotypes to infer orientation (e.g., inferring that fashionable men are gay). Another account, however, argues that people possess a facial perception process that enables them to identify sexual orientation from facial structure (Rule et al., 2008). We report five experiments testing these accounts. Participants made gay-or-straight judgments about fictional targets that were constructed using experimentally-manipulated stereotypic cues and real gay/straight people’s face cues. These studies revealed that orientation is not visible from the face—purportedly “face-based” gaydar arises from a third-variable confound. People do, however, readily infer orientation from stereotypic attributes (e.g., fashion, career). Furthermore, the folk concept of gaydar serves as a legitimizing myth: Compared to a control group, people stereotyped more when led to believe in gaydar, whereas people stereotyped less when told gaydar is an alternate label for stereotyping. Discussion focuses on the implications of the gaydar myth and why, contrary to some prior claims, stereotyping is highly unlikely to result in accurate judgments about orientation. PMID:26219212
5 CFR 5901.102 - Prior approval for outside employment.
Code of Federal Regulations, 2011 CFR
2011-01-01
... activities of a nonprofit charitable, religious, professional, social, fraternal, educational, recreational... study in an institution of higher education, hospital, or similar facility. Professional services means... Alternate DAEO's responsibilities. The FLRA DAEO or Alternate DAEO may issue instructions or manual...
5 CFR 5901.102 - Prior approval for outside employment.
Code of Federal Regulations, 2013 CFR
2013-01-01
... activities of a nonprofit charitable, religious, professional, social, fraternal, educational, recreational... study in an institution of higher education, hospital, or similar facility. Professional services means... Alternate DAEO's responsibilities. The FLRA DAEO or Alternate DAEO may issue instructions or manual...
5 CFR 5901.102 - Prior approval for outside employment.
Code of Federal Regulations, 2012 CFR
2012-01-01
... activities of a nonprofit charitable, religious, professional, social, fraternal, educational, recreational... study in an institution of higher education, hospital, or similar facility. Professional services means... Alternate DAEO's responsibilities. The FLRA DAEO or Alternate DAEO may issue instructions or manual...
Evolutionary Concepts for Decentralized Air Traffic Flow Management
NASA Technical Reports Server (NTRS)
Adams, Milton; Kolitz, Stephan; Milner, Joseph; Odoni, Amedeo
1997-01-01
Alternative concepts for modifying the policies and procedures under which the air traffic flow management system operates are described, and an approach to the evaluation of those concepts is discussed. Here, air traffic flow management includes all activities related to the management of the flow of aircraft and related system resources from 'block to block.' The alternative concepts represent stages in the evolution from the current system, in which air traffic management decision making is largely centralized within the FAA, to a more decentralized approach wherein the airlines and other airspace users collaborate in air traffic management decision making with the FAA. The emphasis in the discussion is on a viable medium-term partially decentralized scenario representing a phase of this evolution that is consistent with the decision-making approaches embodied in proposed Free Flight concepts for air traffic management. System-level metrics for analyzing and evaluating the various alternatives are defined, and a simulation testbed developed to generate values for those metrics is described. The fundamental issue of modeling airline behavior in decentralized environments is also raised, and an example of such a model, which deals with the preservation of flight bank integrity in hub airports, is presented.
NASA Technical Reports Server (NTRS)
Feinberg, A.; Miles, R. F., Jr.
1978-01-01
The principal concepts of the Keeney and Raiffa approach to multiattribute decision analysis are described. Topics discussed include the concepts of decision alternatives, outcomes, objectives, attributes and their states, attribute utility functions, and the necessary independence properties for the attribute states to be aggregated into a numerical representation of the preferences of the decision maker for the outcomes and decision alternatives.
Impact of Context and Representation on Year 10 Students' Expression of Conceptions of Rate
ERIC Educational Resources Information Center
Herbert, Sandra
2010-01-01
Rate is an important, but difficult mathematical concept. More than twenty years of research, especially with calculus students, report difficulties with this concept. This paper reports on an alternative analysis, from the perspective of multiple representations and context, of interviews probing twenty Victorian Year 10 students' conceptions of…
Domain-Specific Self-Concept in Relation to Traditional and Cyber Peer Aggression
ERIC Educational Resources Information Center
Toledano, Shanee; Werch, Brittany L.; Wiens, Brenda A.
2015-01-01
Individuals who aggress against others have been described both as having overall low self-concept and as having high, inflated self-concept. The conceptualization of self-concept as domain specific provides an alternate means to resolving this controversy. In this study, 223 middle school students completed self-report measures assessing…
Spacelab user implementation assessment study. Volume 1: Concept development and evaluation
NASA Technical Reports Server (NTRS)
1975-01-01
The total matrix of alternate Spacelab processing concepts and the rejection rationale utilized to reduce the matrix of 243 alternates to the final candidate processing concepts are developed. The work breakdown structure used for the systematic estimation and compilation of integration and checkout resources is presented along with descriptors of each element. Program models are provided of the space transportation system, the Spacelab, the orbiter, and the ATL that were used as the basis for the study trades, analyses, and optimizations. Resource requirements for all processing concepts are summarized along with the optimizations of the processing concepts. Concept evaluations including flight-rate sensitivities of the GSE, facilities, Spacelab hardware elements, and personnel are delineated. An analysis is presented of the applicability of the candidate concepts to potential spacelab users. The impact of the use of the western test range as an orbiter/spacelab launch site on the candidate processing concepts is evaluated. An assessment of the geographical co-location of experiment, Spacelab, and orbiter-cargo integration is included. Ownership options of the support module/system igloo are discussed.
ERIC Educational Resources Information Center
Finkel, Ed
2017-01-01
The concept that "time is money" applies to the life outlook of community college students as much as anyone. Their success in completing a degree or certificate is often an equation that weighs their financial resources against how long they will need to finish. Prior learning assessments (PLA), which award academic credit for students'…
42 CFR § 414.1460 - Monitoring and program integrity.
Code of Federal Regulations, 2010 CFR
2017-10-01
... SERVICES (CONTINUED) MEDICARE PROGRAM (CONTINUED) PAYMENT FOR PART B MEDICAL AND OTHER HEALTH SERVICES Merit-Based Incentive Payment System and Alternative Payment Model Incentive § 414.1460 Monitoring and program integrity. (a) Vetting eligible clinicians prior to payment of the APM Incentive Payment. Prior to...
Alternative Treatment Technologies – Working With the Pathogen Equivalency Committee
Under current Federal regulations (40 CFR 503), municipal sludge must be treated prior to land application. The regulations identify two classes of treatment with respect to pathogen reduction: Class B (three alternatives) which provides a minimum acceptable level of treatment;...
Modelling Accident Tolerant Fuel Concepts
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hales, Jason Dean; Gamble, Kyle Allan Lawrence
2016-05-01
The catastrophic events that occurred at the Fukushima-Daiichi nuclear power plant in 2011 have led to widespread interest in research of alternative fuels and claddings that are proposed to be accident tolerant. The United States Department of Energy (DOE) through its Nuclear Energy Advanced Modeling and Simulation (NEAMS) program has funded an Accident Tolerant Fuel (ATF) High Impact Problem (HIP). The ATF HIP is a three-year project to perform research on two accident tolerant concepts. The final outcome of the ATF HIP will be an in-depth report to the DOE Advanced Fuels Campaign (AFC) giving a recommendation on whether eithermore » of the two concepts should be included in their lead test assembly scheduled for placement into a commercial reactor in 2022. The two ATF concepts under investigation in the HIP are uranium silicide fuel and iron-chromium-aluminum (FeCrAl) alloy cladding. Utilizing the expertise of three national laboratory participants (Idaho National Laboratory, Los Alamos National Laboratory, and Argonne National Laboratory), a comprehensive multiscale approach to modeling is being used that includes atomistic modeling, molecular dynamics, rate theory, phase-field, and fuel performance simulations. Model development and fuel performance analysis are critical since a full suite of experimental studies will not be complete before AFC must prioritize concepts for focused development. In this paper, we present simulations of the two proposed accident tolerance fuel systems: U3Si2 fuel with Zircaloy-4 cladding, and UO2 fuel with FeCrAl cladding. Sensitivity analyses are completed using Sandia National Laboratories’ Dakota software to determine which input parameters (e.g., fuel specific heat) have the greatest influence on the output metrics of interest (e.g., fuel centerline temperature). We also outline the multiscale modelling approach being employed. Considerable additional work is required prior to preparing the recommendation report for the Advanced Fuels Campaign.« less
48 CFR 34.005-1 - Competition.
Code of Federal Regulations, 2010 CFR
2010-10-01
... between alternative major system concepts and sources, as long as it is economically beneficial and... officer should time solicitation issuance and contract award to maintain continuity of concept development during the transition from withdrawing concept proposer to new contractor. [48 FR 42351, Sept. 19, 1983...
ERIC Educational Resources Information Center
Jewett, John W., Jr.
1991-01-01
Describes science demonstrations with light-emitting diodes that include electrical concepts of resistance, direct and alternating current, sine wave versus square wave, series and parallel circuits, and Faraday's Law; optics concepts of real and virtual images, photoresistance, and optical communication; and modern physics concepts of spectral…
Conceptual coherence of non-Newtonian worldviews in Force Concept Inventory data
NASA Astrophysics Data System (ADS)
Scott, Terry F.; Schumayer, Dániel
2017-06-01
The Force Concept Inventory is one of the most popular and most analyzed multiple-choice concept tests used to investigate students' understanding of Newtonian mechanics. The correct answers poll a set of underlying Newtonian concepts and the coherence of these underlying concepts has been found in the data. However, this inventory was constructed after several years of research into the common preconceptions held by students and using these preconceptions as distractors in the questions. Their sole purpose is to deflect non-Newtonian candidates away from the correct answer. Alternatively, one can argue that the responses could also be treated as polling these preconceptions. In this paper we shift the emphasis of the analysis away from the correlation structure of the correct answers and look at the latent traits underlying the incorrect responses. Our analysis models the data employing exploratory factor analysis, which uses regularities in the data to suggest the existence of underlying structures in the cognitive processing of the students. This analysis allows us to determine whether the data support the claim that there are alternate non-Newtonian worldviews on which students' incorrect responses are based. The existence of such worldviews, and their coherence, could explain the resilience of non-Newtonian preconceptions and would have significant implications to the design of instruction methods. We find that there are indeed coherent alternate conceptions of the world which can be categorized using the results of the research that led to the construction of the Force Concept Inventory.
Blood Donor Test-Seeking Motivation and Prior HIV Testing Experiences in São Paulo, Brazil.
Truong, Hong-Ha M; Blatyta, Paula F; Santos, Fernanda M; Montebello, Sandra; Esposti, Sandra P D; Hangai, Fatima N; Salles, Nanci Alves; Mendrone, Alfredo; Sabino, Ester C; McFarland, Willi; Gonçalez, Thelma T
2015-09-01
HIV test-seeking behavior among blood donors has been observed worldwide and may pose a threat to the safety of the blood supply. We evaluated current test-seeking motivations and prior alternative HIV testing experiences among blood donors in São Paulo, Brazil. All candidate or potential blood donors were consecutively approached and recruited to participate in the study upon presentation at Fundação Pró-Sangue Hemocentro, the largest blood bank in Brazil. Participants were recruited between August 2012 and May 2013 after they were screened for donor eligibility. Questionnaires were administered through audio computer-assisted self-interview. Among 11,867 donors, 38 % previously tested for HIV apart from blood donation, of whom 47.7 % tested at public facilities and 2.7 % acknowledged getting tested for HIV as the primary reason for donating. Dissatisfaction with prior alternative testing experience was reported by 2.5 % of donors. Current test-seeking motivation was associated with dissatisfaction with prior alternative testing experience and testing at a public alternative facility. The most common reasons for dissatisfaction were too long of a wait to get tested and for results, counseling was too long, lack of privacy, and low confidence in the equipment and accuracy of the test. Lack of awareness about the availability of free and confidential public HIV testing services as well as dissatisfaction with past HIV testing and counseling experiences motivate some individuals to test at blood banks. Test-seeking behavior among blood donors may be best addressed by improving alternative testing programs, particularly with respect to time delays, privacy and perceptions about test accuracy. Educational campaigns on safe blood donation and HIV testing for diagnosis, risk counseling and referral to care are also needed for the general public and for health care providers.
NASA Astrophysics Data System (ADS)
Koehler, Karen E.
The purpose of this qualitative study was to explore the use of 3-D printed models as an instructional tool in a middle school science classroom for students with visual impairments and compare their use to traditional tactile graphics for aiding conceptual understanding of geoscience concepts. Specifically, this study examined if the students' conceptual understanding of plate tectonics was different when 3-D printed objects were used versus traditional tactile graphics and explored the misconceptions held by students with visual impairments related to plate tectonics and associated geoscience concepts. Interview data was collected one week prior to instruction and one week after instruction and throughout the 3-week instructional period and additional ata sources included student journals, other student documents and audio taped instructional sessions. All students in the middle school classroom received instruction on plate tectonics using the same inquiry-based curriculum but during different time periods of the day. One group of students, the 3D group, had access to 3-D printed models illustrating specific geoscience concepts and the group of students, the TG group, had access to tactile graphics illustrating the same geoscience concepts. The videotaped pre and post interviews were transcribed, analyzed and coded for conceptual understanding using constant comparative analysis and to uncover student misconceptions. All student responses to the interview questions were categorized in terms of conceptual understanding. Analysis of student journals and classroom talk served to uncover student mental models and misconceptions about plate tectonics and associated geoscience concepts to measure conceptual understanding. A slight majority of the conceptual understanding before instruction was categorized as no understanding or alternative understanding and after instruction the larger majority of conceptual understanding was categorized as scientific or scientific with fragments. Most of the participants in the study increased their scientific understandings of plate tectonics and other geoscience concepts and held more scientific understandings after instruction than before instruction. All students had misconceptions before the instructional period began, but the number of misconceptions were fewer after the instructional period. Students in the TG group not only had fewer misconceptions than the 3D group before instruction, but also after instruction. Many of the student misconceptions were similar to those held by students with typical vision; however, some were unique to students with visual impairments. One unique aspect of this study was the examination of student mental models, which had not previously been done with students with visual impairments, but is more commonplace in research on students with typical vision. Student mental models were often descriptive rather than explanatory, often incorporating scientific language, but not clearly showing that the student had a complete grasp of the concept. Consistent with prior research, the use of 3-D printed models instead of tactile graphics seemed to make little difference either positively or negatively on student conceptual understanding; however, the participants did interact with the 3-D printed models differently, sometimes gleaning additional information from them. This study also provides additional support for inquiry-based instruction as an effective means of science instruction for students with visual impairments.
Yang, Fen; Chen, Jianping; Miao, Mao-Hua; Yuan, Wei; Li, Lin; Liang, Hong; Ehrenstein, Vera; Li, Jiong
2017-01-01
Objective The present study aimed to examine the association between paternal selective serotonin reuptake inhibitor (SSRI) use before conception and the risk of autism spectrum disorder (ASD) in offspring. Design A population-based cohort study. Methods We conducted a cohort study of 669 922 children born from 1998 to 2008, with follow-up throughout 2013. Based on Danish national registers, we linked information on paternal use of SSRIs, ASD diagnosed in children and a range of potential confounders. The children whose fathers used SSRIs during the last 3 months prior to conception were identified as the exposed. Cox regression model was used to estimate the HR for ASD in children. Results Compared with unexposed children, the exposed had a 1.62-fold higher risk of ASD (95% CI 1.33 to 1.96) and the risk attenuated after adjusting for potential confounders, especially fathers’ psychiatric conditions (HR=1.43, 95% CI 1.18 to 1.74). When extending the exposure window to 1 year before conception, the increased risk persisted in children of fathers using SSRIs only from the last year until the last 3 months prior to conception (HR=1.54, 95% CI 1.21 to 1.94) but not in children of fathers using SSRIs only during the last 3 months prior to conception (HR=1.17, 95% CI 0.75 to 1.82). We also performed stratified analyses according to paternal history of affective disorders and observed no increased ASD risk among children whose father had affective disorders. Besides, the sibling analysis showed that the ASD risk did not increase among exposed children compared with their unexposed siblings. Conclusions The mildly increased risk of ASD in the offspring associated with paternal SSRI use before conception may be attributable to paternal underlying psychiatric indications related to SSRI use or other unmeasured confounding factors. PMID:29275337
47 CFR 1.1306 - Actions which are categorically excluded from environmental processing.
Code of Federal Regulations, 2012 CFR
2012-10-01
... aerial corridors of prior or permitted use or the underground installation of wire or cable along existing underground corridors of prior or permitted use, established by the applicant or others. The use of existing buildings, towers or corridors is an environmentally desirable alternative to the...
NASA Technical Reports Server (NTRS)
Smith, G. A.; Meyer, G.
1980-01-01
The results of a simulation study of an alternative design concept for an automatic landing control system are presented. The alternative design concept for an automatic landing control system is described. The design concept is the total aircraft flight control system (TAFCOS). TAFCOS is an open loop, feed forward system that commands the proper instantaneous thrust, angle of attack, and roll angle to achieve the forces required to follow the desired trajector. These dynamic trim conditions are determined by an inversion of the aircraft nonlinear force characteristics. The concept was applied to an A-7E aircraft approaching an aircraft carrier. The implementation details with an airborne digital computer are discussed. The automatic carrier landing situation is described. The simulation results are presented for a carrier approach with atmospheric disturbances, an approach with no disturbances, and for tailwind and headwind gusts.
ERIC Educational Resources Information Center
Itay, Anat
2009-01-01
Progress is a powerful political concept, encompassing different and sometimes contradictory conceptions. This paper examines the results of a survey on progress conducted at the OECD World Forum entitled "Measuring and Fostering the Progress of Societies" held in Istanbul in June 2007. First, a distinction is drawn between the two approaches to…
5 CFR 9201.102 - Prior approval for outside employment and other outside activities.
Code of Federal Regulations, 2012 CFR
2012-01-01
... nonprofit charitable, religious, professional, social, fraternal, educational, recreational, public service... education, hospital or similar facility. Professional services means the provision of personal service by an...) DAEO's and alternate DAEO's responsibilities. The SIGIR DAEO or alternate DAEO may issue instructions...
5 CFR 9201.102 - Prior approval for outside employment and other outside activities.
Code of Federal Regulations, 2011 CFR
2011-01-01
... nonprofit charitable, religious, professional, social, fraternal, educational, recreational, public service... education, hospital or similar facility. Professional services means the provision of personal service by an...) DAEO's and alternate DAEO's responsibilities. The SIGIR DAEO or alternate DAEO may issue instructions...
5 CFR 9201.102 - Prior approval for outside employment and other outside activities.
Code of Federal Regulations, 2013 CFR
2013-01-01
... nonprofit charitable, religious, professional, social, fraternal, educational, recreational, public service... education, hospital or similar facility. Professional services means the provision of personal service by an...) DAEO's and alternate DAEO's responsibilities. The SIGIR DAEO or alternate DAEO may issue instructions...
Piaget's Clay and Descartes' Wax.
ERIC Educational Resources Information Center
Jardine, David W.
1988-01-01
Exploration of a coincidental similarity between the work of Rene Descartes and Jean Piaget relating to the contemporary pedagogical conception of understanding as an active construction of reality points out some of the images that coalesce around this conception and reflects upon alternatives to the conception. (CB)
NASA Astrophysics Data System (ADS)
Barthlow, Michelle J.
2011-12-01
A nonequivalent, control group, pretest-posttest design was used to investigate student achievement in secondary chemistry. This study investigated the effect of process oriented guided inquiry learning (POGIL) in high school chemistry to reduce alternate conceptions related to the particulate nature of matter versus traditional lecture pedagogy. Data were collected from chemistry students in four large high schools and analyzed using ANCOVA. The results show that POGIL pedagogy, as opposed to traditional lecture pedagogy, resulted in fewer alternate conceptions related to the particulate nature of matter. Male and female students in the POGIL group posted better posttest scores than their traditional group peers. African-American and Hispanic students in the POGIL group exhibited achievement gains consistent with Caucasian and Asian students. Further studies are needed to determine the value of POGIL to address achievement gap concerns in chemistry.
Alternative approaches to plasma confinement
NASA Technical Reports Server (NTRS)
Roth, J. R.
1978-01-01
The paper discusses 20 plasma confinement schemes each representing an alternative to the tokamak fusion reactor. Attention is given to: (1) tokamak-like devices (TORMAC, Topolotron, and the Extrap concept), (2) stellarator-like devices (Torsatron and twisted-coil stellarators), (3) mirror machines (Astron and reversed-field devices, the 2XII B experiment, laser-heated solenoids, the LITE experiment, the Kaktus-Surmac concept), (4) bumpy tori (hot electron bumpy torus, toroidal minimum-B configurations), (5) electrostatically assisted confinement (electrostatically stuffed cusps and mirrors, electrostatically assisted toroidal confinement), (6) the Migma concept, and (7) wall-confined plasmas. The plasma parameters of the devices are presented and the advantages and disadvantages of each are listed.
Life extending control: A concept paper
NASA Technical Reports Server (NTRS)
Lorenzo, Carl F.; Merrill, Walter C.
1991-01-01
The concept of Life Extending Control is defined. Life is defined in terms of mechanical fatigue life. A brief description is given of the current approach to life prediction using a local, cyclic, stress-strain approach for a critical system component. An alternative approach to life prediction based on a continuous functional relationship to component performance is proposed.Base on cyclic life prediction an approach to Life Extending Control, called the Life Management Approach is proposed. A second approach, also based on cyclic life prediction, called the Implicit Approach, is presented. Assuming the existence of the alternative functional life prediction approach, two additional concepts for Life Extending Control are presented.
ERIC Educational Resources Information Center
Zeilik, Michael; Morris-Dueer, Vicki J.
2004-01-01
In the summers of 1997, 1998, and 1999, we gave attendees (N=44) at a workshop called Teaching Astronomy Conceptually a cognitive task: to rank 200 concepts often taught in "Astronomy 101." Prior to these workshops, we asked an expert panel (N=18) of Astronomy 101 teachers to also rank these concepts. Among the workshop participants, the…
49 CFR 236.913 - Filing and approval of PSPs.
Code of Federal Regulations, 2011 CFR
2011-10-01
... architectural concepts; the PSP describes a product that uses design or safety assurance concepts considered... the end of the system design review phase of product development and 180 days prior to planned implementation, inviting FRA to participate in the design review process and receive periodic briefings and...
49 CFR 236.913 - Filing and approval of PSPs.
Code of Federal Regulations, 2010 CFR
2010-10-01
... architectural concepts; the PSP describes a product that uses design or safety assurance concepts considered... the end of the system design review phase of product development and 180 days prior to planned implementation, inviting FRA to participate in the design review process and receive periodic briefings and...
Concept of the Exponential Law Prior to 1900
ERIC Educational Resources Information Center
Curtis, Lorenzo J.
1978-01-01
Presents the historical development of perceptions and applications of the exponential law, tracing it from its ancient origins until the year 1900. Shows that many concepts such as mean life and half life and their relationships to differential equations were known long before their application to nuclear radioactivity. (GA)
Making Science Misconceptions Work for Us
ERIC Educational Resources Information Center
Elliott, Katrina; Pillman, Anne
2016-01-01
This paper explores strategies for teachers to work with science conceptions, both those consistent and those inconsistent with western science understanding. It emphasises the value of teachers checking their own and their students' prior understanding of concepts to be learnt. A past approach of educators has been to replace old beliefs with new…
OTEC modular experiment cold water pipe concept evaluation. Volume III. Appendices
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1979-04-01
The Cold Water Pipe System Design Study was undertaken to evaluate the diverse CWP concepts, recommend the most viable alternatives for a 1984 deployment of the 10 to 40 MWe MEP, and carry out preliminary designs of three concepts. The concept evaluation phase reported involved a systems analysis of design alternatives in the broad categories of rigid walled (with hinges), compliant walled, stockade and bottom mounted buoyant. Quantitative evaluations were made of concept performance, availability, deployment schedule, technical feasibility and cost. CWP concepts were analyzed to determine if they met or could be made to meet established system requirements andmore » could be deployed by 1984. Fabrication, construction and installation plans were developed for successful concepts, and costs were determined in a WBS format. Evaluations were performed on the basis of technical and cost risk. This volume includes the following appendices: (A) materials and associated design criteria; (B) summary of results of dynamic flow and transportation analysis; (C) CWP sizing analysis; (D) CWP thermal performance; and (E) investigation of the APL/ABAM CWP design. (WHK)« less
Conditions for Self-Confidence among Boys and Girls Achieving Highly in Chemistry.
ERIC Educational Resources Information Center
Ziegler, Albert; Heller, Kurt A.
2000-01-01
Students (N=379) in the 8th grade of German college preparatory schools, prior to formal chemistry instruction, were evaluated for prior knowledge of chemistry, their self-concept regarding chemistry, their gender-bound attitudes toward chemistry, and their fear of chemistry. Findings indicated that girls already expressed significantly lower…
Prior-to-Exam: What Activities Enhance Performance?
ERIC Educational Resources Information Center
Rhoads, C. J.; Healy, Therese
2013-01-01
Can instructors impact their student performance by recommending an activity just prior to taking an exam? In this study, college students were randomly assigned to one of three treatment groups (study, exercise, or meditation) or a control group. Each group was given two different types of tests; a traditional concept exam, and a non-traditional…
USDA-ARS?s Scientific Manuscript database
Previous reports suggest increased circulating concentrations of estradiol prior to GnRH induced ovulation improved conception rates and pregnancy maintenance in beef cattle, and cultured granulosa cells from animals with high antral follicle numbers produced more estradiol and had increased express...
Development of a Low Inductance Linear Alternator for Stirling Power Convertors
NASA Technical Reports Server (NTRS)
Geng, Steven M.; Schifer, Nicholas A.
2017-01-01
The free-piston Stirling power convertor is a promising technology for high efficiency heat-to-electricity power conversion in space. Stirling power convertors typically utilize linear alternators for converting mechanical motion into electricity. The linear alternator is one of the heaviest components of modern Stirling power convertors. In addition, state-of-art Stirling linear alternators usually require the use of tuning capacitors or active power factor correction controllers to maximize convertor output power. The linear alternator to be discussed in this paper, eliminates the need for tuning capacitors and delivers electrical power output in which current is inherently in phase with voltage. No power factor correction is needed. In addition, the linear alternator concept requires very little iron, so core loss has been virtually eliminated. This concept is a unique moving coil design where the magnetic flux path is defined by the magnets themselves. This paper presents computational predictions for two different low inductance alternator configurations, and compares the predictions with experimental data for one of the configurations that has been built and is currently being tested.
Development of a Low-Inductance Linear Alternator for Stirling Power Convertors
NASA Technical Reports Server (NTRS)
Geng, Steven M.; Schifer, Nicholas A.
2017-01-01
The free-piston Stirling power convertor is a promising technology for high-efficiency heat-to-electricity power conversion in space. Stirling power convertors typically utilize linear alternators for converting mechanical motion into electricity. The linear alternator is one of the heaviest components of modern Stirling power convertors. In addition, state-of-the-art Stirling linear alternators usually require the use of tuning capacitors or active power factor correction controllers to maximize convertor output power. The linear alternator to be discussed in this paper eliminates the need for tuning capacitors and delivers electrical power output in which current is inherently in phase with voltage. No power factor correction is needed. In addition, the linear alternator concept requires very little iron, so core loss has been virtually eliminated. This concept is a unique moving coil design where the magnetic flux path is defined by the magnets themselves. This paper presents computational predictions for two different low inductance alternator configurations. Additionally, one of the configurations was built and tested at GRC, and the experimental data is compared with the predictions.
[Complementary and alternative medicine in oncology].
Hübner, J
2013-06-01
Complementary and alternative medicine are frequently used by cancer patients. The main benefit of complementary medicine is that it gives patients the chance to become active. Complementary therapy can reduce the side effects of conventional therapy. However, we have to give due consideration to side effects and interactions: the latter being able to reduce the effectiveness of cancer therapy and so to jeopardise the success of therapy. Therefore, complementary therapy should be managed by the oncologist. It is based on a common concept of cancerogenesis with conventional therapy. Complement therapy can be assessed in studies. Alternative medicine in contrast rejects common rules of evidence-based medicine. It starts from its own concepts of cancerogenesis, which is often in line with the thinking of lay persons. Alternative medicine is offered as either "alternative" to recommended cancer treatment or is used at the same time but without due regard for the interactions. Alternative medicine is a high risk to patients. In the following two parts of the article, the most important complementary and alternative therapies cancer patients use nowadays are presented and assessed according to published evidence.
DOT National Transportation Integrated Search
1982-01-01
Transportation Research Record 886 addresses "New Concepts in Data Analysis." The following papers are included within: "Origin-Destination Travel Survey for Southeast Michigan;" "Pilot Testing of Alternative Administrative Procedures and Survey Inst...
NASA Astrophysics Data System (ADS)
Lucero, Margaret M.; Petrosino, Anthony J.
2017-08-01
The Conceptual Inventory of Natural Selection (CINS) is an example of a research-based instrument that assesses conceptual understanding in an area that contains well-documented alternative conceptions. Much of the CINS's use and original validation has been relegated to undergraduate settings, but the information learned from student responses on the CINS can also potentially be a useful resource for teachers at the secondary level. Because of its structure, the CINS can have a role in eliciting alternative conceptions and induce deeper conceptual understanding by having student ideas leveraged during instruction. In a first step toward this goal, the present study further investigated the CINS's internal properties by having it administered to a group ( n = 339) of students among four different biology teachers at a predominantly Latino, economically disadvantaged high school. In addition, incidences of the concept inventory's use among the teachers' practices were collected for support of its adaptability at the secondary level. Despite the teachers' initial enthusiasm for the CINS's use as an assessment tool in the present study, results from a principal components analysis demonstrate inconsistencies between the original and present validations. Results also reveal how the teachers think CINS items may be revised for future use among secondary student populations.
NASA Astrophysics Data System (ADS)
Gonzaga, E. P.
2016-05-01
This work deals with the analysis of scientific and alternative astronomical concepts found in the responses of teachers who teach classes Science, Geography and Physic in Basic Education (BE) of the state of the North Coast of São Paulo and how to address the alternative astronomical concepts with students from students Fundamental Education (FE) and Medium Education (ME). Bringing the legal documents regarding the Astronomy in BE, within the national and the São Paulo regions curriculum level, also with rationed researches to the teacher's formation, conceptual errors in books, knowledge non-formal spaces, alternative concepts, Astronomical studies and content analysis for fundamental theoretical. The task executed with the teachers was done via Technical Orientations (TO), promoted by the Director of Education (DE) from Caraguatatuba and region, with the premise to threat the continuous formation giving moments of discussion, practical activities and using the Digital Mobile Planetarium (DMP) with non-formal spaces of knowledge to the Astronomical studies gathering data via questions. Within the analysis of the answers analysis by the teachers, tables were created with the categories that highlight actual situations on the astronomical studies in the North Coast of São Paulo, and demarked the possible paths where the continuous formation will be followed in the future. Aspects checked in the survey were highlighted; such as teachers understand that they need continuing education; teachers have scientific astronomical views on various aspects know to teach concepts of Astronomy at BE; TO is a viable option as continued training and the use of DMP as no formal teaching and learning.
Simulation and Flight Control of an Aeroelastic Fixed Wing Micro Aerial Vehicle
NASA Technical Reports Server (NTRS)
Waszak, Martin; Davidson, John B.; Ifju, Peter G.
2002-01-01
Micro aerial vehicles have been the subject of continued interest and development over the last several years. The majority of current vehicle concepts rely on rigid fixed wings or rotors. An alternate design based on an aeroelastic membrane wing has also been developed that exhibits desired characteristics in flight test demonstrations, competition, and in prior aerodynamics studies. This paper presents a simulation model and an assessment of flight control characteristics of the vehicle. Linear state space models of the vehicle associated with typical trimmed level flight conditions and which are suitable for control system design are presented as well. The simulation is used as the basis for the design of a measurement based nonlinear dynamic inversion control system and outer loop guidance system. The vehicle/controller system is the subject of ongoing investigations of autonomous and collaborative control schemes. The results indicate that the design represents a good basis for further development of the micro aerial vehicle for autonomous and collaborative controls research.
Salton Sea Ecosystem Monitoring Project
Miles, A. Keith; Ricca, Mark A.; Meckstroth, Anne; Spring, Sarah E.
2009-01-01
The Salton Sea is critically important for wintering and breeding waterbirds, but faces an uncertain future due to water delivery reductions imposed by the Interstate and Federal Quantification Settlement Agreement of 2003. The current preferred alternative for wetland restoration at the Salton Sea is saline habitat impoundments created to mitigate the anticipated loss of wetland habitat. In 2006, a 50-hectare experimental complex that consisted of four inter-connected, shallow water saline habitat ponds (SHP) was constructed at the southeastern shoreline of the Salton Sea and flooded with blended waters from the Alamo River and Salton Sea. The present study evaluated ecological risks and benefits of the SHP concept prior to widespread restoration actions. This study was designed to evaluate (1) baseline chemical, nutrient, and contaminant measures from physical and biological constituents, (2) aquatic invertebrate community structure and colonization patterns, and (3) productivity of and contaminant risks to nesting waterbirds at the SHP. These factors were evaluated and compared with those of nearby waterbird habitat, that is, reference sites.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lim, Yong Chae; Sanderson, Samuel; Mahoney, Murray
Friction stir welding (FSW) has recently attracted attention as an alternative construction process for gas/oil transportation applications due to advantages compared to fusion welding techniques. A significant advantage is the ability of FSW to weld the entire or nearly the entire wall thickness in a single pass, while fusion welding requires multiple passes. However, when FSW is applied to a pipe or tube geometry, an internal back support anvil is required to resist the plunging forces exerted during FSW. Unfortunately, it may not be convenient or economical to use internal backing support due to limited access for some applications. Tomore » overcome this issue, ExxonMobil recently developed a new concept, combining root arc welding and FSW. That is, a root arc weld is made prior to FSW that supports the normal loads associated with FSW. In the present work, mechanical properties of a FSW + root arc welded pipe steel are reported including microstructure and microhardness.« less
How Moral Threat Shapes Laypersons' Engagement With Science.
Bender, Jens; Rothmund, Tobias; Nauroth, Peter; Gollwitzer, Mario
2016-12-01
Laypersons' engagement with science has grown over the last decade, especially in Internet environments. While this development has many benefits, scientists also face the challenge of devaluation and public criticism by laypersons. Embedding this phenomenon in social-psychological theories and research on value-behavior correspondence, we investigated moral threat as a factor influencing laypersons' engagement with science. Across three studies, we hypothesized and found that moral values shape the way laypersons evaluate and communicate about science when these values are threatened in a given situation and central to people's self-concept. However, prior research on the underlying mechanism of moral threat effects cannot fully rule out value salience as an alternative explanation. To close this gap, we situationally induced value salience while varying the degree of moral threat (Study 3). Our findings indicate that moral threat amplifies the influence of moral values on laypersons' evaluation of science above and beyond value salience. © 2016 by the Society for Personality and Social Psychology, Inc.
ERIC Educational Resources Information Center
Abraham, Joel K.; Perez, Kathryn E.; Price, Rebecca M.
2014-01-01
Despite the impact of genetics on daily life, biology undergraduates understand some key genetics concepts poorly. One concept requiring attention is dominance, which many students understand as a fixed property of an allele or trait and regularly conflate with frequency in a population or selective advantage. We present the Dominance Concept…
ERIC Educational Resources Information Center
Maries, Alexandru; Singh, Chandralekha
2016-01-01
The Force Concept Inventory (FCI) has been widely used to assess student understanding of introductory mechanics concepts by a variety of educators and physics education researchers. One reason for this extensive use is that many of the items on the FCI have strong distractor choices which correspond to students' alternate conceptions in…
ERIC Educational Resources Information Center
Trumper, Ricardo
2006-01-01
In view of students' alternative conceptions about basic concepts in astronomy, we conducted a series of constructivist activities with future elementary and junior high school teachers aimed at changing their conceptions about the cause of seasonal changes, and of several characteristics of the Sun-Earth-Moon relative movements like Moon phases,…
ERIC Educational Resources Information Center
Lucero, Margaret M.; Petrosino, Anthony J.; Delgado, Cesar
2017-01-01
The fundamental scientific concept of evolution occurring by natural selection is home to many deeply held alternative conceptions and considered difficult to teach. Science teachers' subject matter knowledge (SMK) and the pedagogical content knowledge (PCK) component of knowledge of students' conceptions (KOSC) can be valuable resources for…
1999-10-21
Travel to distant stars is a long-range goal of Marshall Space Flight Center's Advanced Concept Group. One of the many propulsion systems currently being studied is fusion power. The objective of this and many other alternative propulsion systems is to reduce the costs of space access and to reduce the travel time for planetary missions. One of the major factors is providing an alternate engery source for these missions. Pictured is an artist's concept of future interplanetary space flight using fusion power.
Biedermann, Alex; Taroni, Franco; Margot, Pierre
2012-01-31
Prior probabilities represent a core element of the Bayesian probabilistic approach to relatedness testing. This letter opinions on the commentary Use of prior odds for missing persons identifications by Budowle et al., published recently in this journal. Contrary to Budowle et al., we argue that the concept of prior probabilities (i) is not endowed with the notion of objectivity, (ii) is not a case for computation, and (iii) does not require new guidelines edited by the forensic DNA community--as long as probability is properly considered as an expression of personal belief.
NASA Technical Reports Server (NTRS)
Mazanek, D. D.; Abell, P. A.; Antol, J.; Barbee, B. W.; Beaty, D. W.; Bass, D. S.; Castillo-Rogez, J. C.; Coan, D. A.; Colaprete, A.; Daugherty, K. J.;
2012-01-01
The National Aeronautics and Space Administration s Human Spaceflight Architecture Team (HAT) has been developing a preliminary Destination Mission Concept (DMC) to assess how a human orbital mission to one or both of the Martian moons, Phobos and Deimos, might be conducted as a follow-on to a human mission to a near-Earth asteroid (NEA) and as a possible preliminary step prior to a human landing on Mars. The HAT Mars-Phobos-Deimos (MPD) mission also permits the teleoperation of robotic systems by the crew while in the Mars system. The DMC development activity provides an initial effort to identify the science and exploration objectives and investigate the capabilities and operations concepts required for a human orbital mission to the Mars system. In addition, the MPD Team identified potential synergistic opportunities via prior exploration of other destinations currently under consideration.
Carballa, Marta; Duran, Cecilia; Hospido, Almudena
2011-12-15
Many studies have shown the effectiveness of pretreatments prior to anaerobic digestion of solid wastes, but to our knowledge, none analyzes their environmental consequences/costs. In this work, seven different pretreatments applied to two types of waste (kitchen waste and sewage sludge) have been environmentally evaluated by using life cycle assessment (LCA) methodology. The results show that the environmental burdens associated to the application of pretreatments prior to anaerobic digestion cannot be excluded. Among the options tested, the pressurize-depressurize and chemical (acid or alkaline) pretreatments could be recommended on the basis of their beneficial net environmental performance, while thermal and ozonation alternatives require energy efficiency optimization to reduce their environmental burdens. Reconciling operational, economic and environmental aspects in a holistic approach for the selection of the most sustainable option, mechanical (e.g., pressurize-depressurize) and chemical methods appear to be the most appropriate alternatives at this stage.
Use of uninformative priors to initialize state estimation for dynamical systems
NASA Astrophysics Data System (ADS)
Worthy, Johnny L.; Holzinger, Marcus J.
2017-10-01
The admissible region must be expressed probabilistically in order to be used in Bayesian estimation schemes. When treated as a probability density function (PDF), a uniform admissible region can be shown to have non-uniform probability density after a transformation. An alternative approach can be used to express the admissible region probabilistically according to the Principle of Transformation Groups. This paper uses a fundamental multivariate probability transformation theorem to show that regardless of which state space an admissible region is expressed in, the probability density must remain the same under the Principle of Transformation Groups. The admissible region can be shown to be analogous to an uninformative prior with a probability density that remains constant under reparameterization. This paper introduces requirements on how these uninformative priors may be transformed and used for state estimation and the difference in results when initializing an estimation scheme via a traditional transformation versus the alternative approach.
NOBLE - Flexible concept recognition for large-scale biomedical natural language processing.
Tseytlin, Eugene; Mitchell, Kevin; Legowski, Elizabeth; Corrigan, Julia; Chavan, Girish; Jacobson, Rebecca S
2016-01-14
Natural language processing (NLP) applications are increasingly important in biomedical data analysis, knowledge engineering, and decision support. Concept recognition is an important component task for NLP pipelines, and can be either general-purpose or domain-specific. We describe a novel, flexible, and general-purpose concept recognition component for NLP pipelines, and compare its speed and accuracy against five commonly used alternatives on both a biological and clinical corpus. NOBLE Coder implements a general algorithm for matching terms to concepts from an arbitrary vocabulary set. The system's matching options can be configured individually or in combination to yield specific system behavior for a variety of NLP tasks. The software is open source, freely available, and easily integrated into UIMA or GATE. We benchmarked speed and accuracy of the system against the CRAFT and ShARe corpora as reference standards and compared it to MMTx, MGrep, Concept Mapper, cTAKES Dictionary Lookup Annotator, and cTAKES Fast Dictionary Lookup Annotator. We describe key advantages of the NOBLE Coder system and associated tools, including its greedy algorithm, configurable matching strategies, and multiple terminology input formats. These features provide unique functionality when compared with existing alternatives, including state-of-the-art systems. On two benchmarking tasks, NOBLE's performance exceeded commonly used alternatives, performing almost as well as the most advanced systems. Error analysis revealed differences in error profiles among systems. NOBLE Coder is comparable to other widely used concept recognition systems in terms of accuracy and speed. Advantages of NOBLE Coder include its interactive terminology builder tool, ease of configuration, and adaptability to various domains and tasks. NOBLE provides a term-to-concept matching system suitable for general concept recognition in biomedical NLP pipelines.
Concept Inventories: Predicting the Wrong Answer May Boost Performance
ERIC Educational Resources Information Center
Talanquer, Vincente
2017-01-01
Several concept inventories have been developed to elicit students' alternative conceptions in chemistry. It is suggested that heuristic reasoning may bias students' answers in these types of assessments toward intuitively appealing choices. If this is the case, one could expect students to improve their performance by engaging in more analytical…
Alternative Conceptions of Wisdom: An Onion-Peeling Exercise.
ERIC Educational Resources Information Center
Blanchard-Fields, Fredda; And Others
1987-01-01
Discusses contextualistic and integrative approaches to the concept of wisdom, and the evolution of the concept from an independent construct of intelligence to a component of intelligence, i.e., practical intelligence. Suggests operationalization of wisdom as the ability to integrate cognition and affect. Illustrates the integrative approach with…
7 CFR 11.5 - Informal review of adverse decisions.
Code of Federal Regulations, 2011 CFR
2011-01-01
... participant also shall have the right to utilize any available alternative dispute resolution (ADR) or... prior to a NAD hearing. If a participant: (1) Requests mediation or ADR prior to filing an appeal with... once mediation or ADR has concluded. (2) Requests mediation or ADR after having filed an appeal to NAD...
Hepa filter dissolution process
Brewer, Ken N.; Murphy, James A.
1994-01-01
A process for dissolution of spent high efficiency particulate air (HEPA) filters and then combining the complexed filter solution with other radioactive wastes prior to calcining the mixed and blended waste feed. The process is an alternate to a prior method of acid leaching the spent filters which is an inefficient method of treating spent HEPA filters for disposal.
30 CFR 75.1506 - Refuge alternatives.
Code of Federal Regulations, 2013 CFR
2013-07-01
... Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH... unit consisting of 15 psi stoppings constructed prior to an event in a secure space and an isolated.... Refuge alternatives consisting of materials pre-positioned for miners to deploy in a secure space with an...
30 CFR 75.1506 - Refuge alternatives.
Code of Federal Regulations, 2012 CFR
2012-07-01
... Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH... unit consisting of 15 psi stoppings constructed prior to an event in a secure space and an isolated.... Refuge alternatives consisting of materials pre-positioned for miners to deploy in a secure space with an...
30 CFR 75.1506 - Refuge alternatives.
Code of Federal Regulations, 2014 CFR
2014-07-01
... Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH... unit consisting of 15 psi stoppings constructed prior to an event in a secure space and an isolated.... Refuge alternatives consisting of materials pre-positioned for miners to deploy in a secure space with an...
The Importance of Proving the Null
ERIC Educational Resources Information Center
Gallistel, C. R.
2009-01-01
Null hypotheses are simple, precise, and theoretically important. Conventional statistical analysis cannot support them; Bayesian analysis can. The challenge in a Bayesian analysis is to formulate a suitably vague alternative, because the vaguer the alternative is (the more it spreads out the unit mass of prior probability), the more the null is…
Authorship Attribution with Function Word N-Grams
ERIC Educational Resources Information Center
Johnson, Rusty
2013-01-01
Prior research has considered the sequential order of function words, after the contextual words of the text have been removed, as a stylistic indicator of authorship. This research describes an effort to enhance authorship attribution accuracy based on this same information source with alternate classifiers, alternate n-gram construction methods,…
Alternative Youth Employment Strategies Project: Final Report.
ERIC Educational Resources Information Center
Sadd, Susan; And Others
The Alternative Youth Employment Strategies (AYES) Project began as one of the demonstration projects funded under the Youth Employment and Demonstration Project Act in 1980. The program, which features three training models, is targeted toward high-risk, disadvantaged youth, especially minority youths from urban areas who had prior involvement…
Code of Federal Regulations, 2011 CFR
2011-01-01
... 10 Energy 4 2011-01-01 2011-01-01 false Fuels search. 503.14 Section 503.14 Energy DEPARTMENT OF ENERGY (CONTINUED) ALTERNATE FUELS NEW FACILITIES General Requirements for Exemptions § 503.14 Fuels search. Prior to submitting a petition for a permanent exemption for lack of alternate fuel supply, site...
Code of Federal Regulations, 2012 CFR
2012-01-01
... 10 Energy 4 2012-01-01 2012-01-01 false Fuels search. 503.14 Section 503.14 Energy DEPARTMENT OF ENERGY (CONTINUED) ALTERNATE FUELS NEW FACILITIES General Requirements for Exemptions § 503.14 Fuels search. Prior to submitting a petition for a permanent exemption for lack of alternate fuel supply, site...
Code of Federal Regulations, 2014 CFR
2014-01-01
... 10 Energy 4 2014-01-01 2014-01-01 false Fuels search. 503.14 Section 503.14 Energy DEPARTMENT OF ENERGY (CONTINUED) ALTERNATE FUELS NEW FACILITIES General Requirements for Exemptions § 503.14 Fuels search. Prior to submitting a petition for a permanent exemption for lack of alternate fuel supply, site...
Code of Federal Regulations, 2013 CFR
2013-01-01
... 10 Energy 4 2013-01-01 2013-01-01 false Fuels search. 503.14 Section 503.14 Energy DEPARTMENT OF ENERGY (CONTINUED) ALTERNATE FUELS NEW FACILITIES General Requirements for Exemptions § 503.14 Fuels search. Prior to submitting a petition for a permanent exemption for lack of alternate fuel supply, site...
Students' understandings of electrochemistry
NASA Astrophysics Data System (ADS)
O'Grady-Morris, Kathryn
Electrochemistry is considered by students to be a difficult topic in chemistry. This research was a mixed methods study guided by the research question: At the end of a unit of study, what are students' understandings of electrochemistry? The framework of analysis used for the qualitative and quantitative data collected in this study was comprised of three categories: types of knowledge used in problem solving, levels of representation of knowledge in chemistry (macroscopic, symbolic, and particulate), and alternative conceptions. Although individually each of the three categories has been reported in previous studies, the contribution of this study is the inter-relationships among them. Semi-structured, task-based interviews were conducted while students were setting up and operating electrochemical cells in the laboratory, and a two-tiered, multiple-choice diagnostic instrument was designed to identify alternative conceptions that students held at the end of the unit. For familiar problems, those involving routine voltaic cells, students used a working-forwards problem-solving strategy, two or three levels of representation of knowledge during explanations, scored higher on both procedural and conceptual knowledge questions in the diagnostic instrument, and held fewer alternative conceptions related to the operation of these cells. For less familiar problems, those involving non-routine voltaic cells and electrolytic cells, students approached problem-solving with procedural knowledge, used only one level of representation of knowledge when explaining the operation of these cells, scored higher on procedural knowledge than conceptual knowledge questions in the diagnostic instrument, and held a greater number of alternative conceptions. Decision routines that involved memorized formulas and procedures were used to solve both quantitative and qualitative problems and the main source of alternative conceptions in this study was the overgeneralization of theory related to the particulate level of representation of knowledge. The findings from this study may contribute further to our understanding of students' conceptions in electrochemistry. Furthermore, understanding the influence of the three categories in the framework of analysis and their inter-relationships on how students make sense of this field may result in a better understanding of classroom practice that could promote the acquisition of conceptual knowledge --- knowledge that is "rich in relationships".
Chemical Safety Alert: Safer Technology and Alternatives
This alert is intended to introduce safer technology concepts and general approaches, explains the concepts and principles, and gives brief examples of the integration of safer technologies into facility risk management activities.
Engineering principles to assure compatible docking between future spacecraft of USA and USSR
NASA Technical Reports Server (NTRS)
Johnson, C. C.
1975-01-01
Working jointly the USA and the USSR have selected an androgynous, peripheral type docking mechanism concept. The mechanical principles inherent to the concept, the rationale supporting its selection, and the probable nature of future designs stemming from the concept, are described. Operational situations just prior to docking, impact conditions, energy absorption, and the structural joining of the spacecraft, are specified. Docking procedures for the Apollo-Soyuz missions are discussed.
Teaching as Jesus Making: The Hidden Curriculum of Christ in Schooling
ERIC Educational Resources Information Center
Burke, Kevin J.; Segall, Avner
2015-01-01
Background/Context: The ideas of teaching as salvation and teacher-as-martyr are not new concepts. Prior research, however, has largely failed to explore the historical and cultural religious roots that continue to inform the ways in which teachers are constructed. That is, though prior work has engaged with thinking about religion and thinking…
ERIC Educational Resources Information Center
Yang, Wen-Tsung; Lin, Yu-Ren; She, Hsiao-Ching; Huang, Kai-Yi
2015-01-01
This study investigated the effects of students' prior science knowledge and online learning approaches (social and individual) on their learning with regard to three topics: science concepts, inquiry, and argumentation. Two science teachers and 118 students from 4 eighth-grade science classes were invited to participate in this research. Students…
Computer Literacy Project. A General Orientation in Basic Computer Concepts and Applications.
ERIC Educational Resources Information Center
Murray, David R.
This paper proposes a two-part, basic computer literacy program for university faculty, staff, and students with no prior exposure to computers. The program described would introduce basic computer concepts and computing center service programs and resources; provide fundamental preparation for other computer courses; and orient faculty towards…
ERIC Educational Resources Information Center
Murphy, Amanda; Terrizzi, Marissa; Cormas, Peter
2012-01-01
"Probability is a difficult concept to teach, because children and adults find it counterintuitive." This is impetus to consider the detailed planning of a set of lessons with a "mixed", in many senses, group of fourth graders. Can the use of prior experience, and the knowledge associated with that experience, make probability a concept that is…
Commentary: A Summary and Analysis of Twenty-Seven Years of Geoscience Conceptions Research
ERIC Educational Resources Information Center
Cheek, Kim A.
2010-01-01
Seventy-nine studies in geoscience conceptions appeared in peer-reviewed publications in English from 1982 through July 2009. Summaries of the 79 studies suggest certain recurring themes across subject areas: issues with terms, scale (temporal and spatial), role of prior experience, and incorrect application of everyday knowledge to geoscience…
ERIC Educational Resources Information Center
Balgopal, Meena M.; Montplaisir, Lisa M.
2011-01-01
The process of reflective writing can play a central role in making meaning as learners process new information and connect it to prior knowledge. An examination of the written discourse can therefore be revealing of learners' cognitive understanding and affective (beliefs, feelings, motivation to learn) responses to concepts. Despite reflective…
Designing Project-Enhanced Environments
ERIC Educational Resources Information Center
Wilhelm, Jennifer; Confey, Jere
2005-01-01
The concept of waves is fundamental due to its occurrence throughout the natural world. Because the concept occurs in so many places, students come to the classroom with prior knowledge, as well as misconceptions, about waves. Students have misconceptions about what is waving in a wave, what properties of the medium determine wave speed, and how…
Novel Surface Transportation Modes
DOT National Transportation Integrated Search
2015-12-01
This report summarizes an initial stage investigation into current research and development of alternative modal concepts. The project goals were to gain a better understanding of novel surface transportation concepts that fall outside of the Federal...
Small V/STOL aircraft analysis, volume 1
NASA Technical Reports Server (NTRS)
Smith, K. R., Jr.; Belina, F. W.
1974-01-01
A study has been made of the economic viability of advanced V/STOL aircraft concepts in performing general aviation missions. A survey of general aviation aircraft users, operators, and manufacturers indicated that personnel transport missions formulated around business executive needs, commuter air service, and offshore oil supply are the leading potential areas of application using VTOL aircraft. Advanced VTOL concepts potentially available in the late 1970 time period were evaluated as alternatives to privately owned contemporary aircraft and commercial airline service in satisfying these personnel transport needs. Economic analysis incorporating the traveler's value of time as the principle figure of merit were used to identify the relative merits of alternative VTOL air transportation concepts.
ERIC Educational Resources Information Center
Won, Mihye; Krabbe, Heiko; Ley, Siv Ling; Treagust, David F.; Fischer, Hans E.
2017-01-01
In this study, we investigated the value of a concept map marking guide as an alternative formative assessment tool for science teachers to adopt for the topic of energy. Eight high school science teachers marked students' concept maps using an itemized holistic marking guide. Their marking was compared with the researchers' marking and the scores…
Soederberg Miller, Lisa M; Gibson, Tanja N; Applegate, Elizabeth A; de Dios, Jeannette
2011-07-01
Prior knowledge, working memory capacity (WMC), and conceptual integration (attention allocated to integrating concepts in text) are critical within many contexts; however, their impact on the acquisition of health information (i.e. learning) is relatively unexplored.We examined how these factors impact learning about nutrition within a cross-sectional study of adults ages 18 to 81. Results showed that conceptual integration mediated the effects of knowledge and WMC on learning, confirming that attention to concepts while reading is important for learning about health. We also found that when knowledge was controlled, age declines in learning increased, suggesting that knowledge mitigates the effects of age on learning about nutrition.
NASA Astrophysics Data System (ADS)
Slykhuis, David A.
This research project examined the efficacy of an online microcomputer-based laboratory based (MBL) physics unit. One hundred and fifty physics students from five high schools in North Carolina were divided into online and classroom groups. The classroom group completed the MBL unit in small groups with assistance from their teachers. The online groups completed the MBL unit in small groups using a website designed for this project for guidance. Pre- and post-unit content specific tests and surveys were given. Statistical analysis of the content tests showed significant development of conceptual understanding by the online group over the course of the unit. There was not a significant difference between the classroom and online group with relation to the amount of conceptual understanding developed. Correlations with post-test achievement showed that pre-test scores and math background were the most significant correlates with success. Computer related variables, such as computer comfort and online access, were only mildly correlated with the online group. Students' views about the nature of physics were not well developed prior to the unit and did not significantly change over the course of the unit. Examination of the students' physics conceptions after instruction revealed common alternative conceptions such as confusing position and velocity variables and incorrect interpretations of graphical features such as slope.
The construction of causal schemes: learning mechanisms at the knowledge level.
diSessa, Andrea A
2014-06-01
This work uses microgenetic study of classroom learning to illuminate (1) the role of pre-instructional student knowledge in the construction of normative scientific knowledge, and (2) the learning mechanisms that drive change. Three enactments of an instructional sequence designed to lead to a scientific understanding of thermal equilibration are used as data sources. Only data from a scaffolded student inquiry preceding introduction of a normative model were used. Hence, the study involves nearly autonomous student learning. In two classes, students developed stable and socially shared explanations ("causal schemes") for understanding thermal equilibration. One case resulted in a near-normative understanding, while the other resulted in a non-normative "alternative conception." The near-normative case seems to be a particularly clear example wherein the constructed causal scheme is a composition of previously documented naïve conceptions. Detailed prior description of these naive elements allows a much better than usual view of the corresponding details of change during construction of the new scheme. A list of candidate mechanisms that can account for observed change is presented. The non-normative construction seems also to be a composition, albeit of a different structural form, using a different (although similar) set of naïve elements. This article provides one of very few high-resolution process analyses showing the productive use of naïve knowledge in learning. © 2014 Cognitive Science Society, Inc.
Careful! It Is H[subscript 2]O? Teachers' Conceptions of Chemicals
ERIC Educational Resources Information Center
Salloum, Sara L.; BouJaoude, Saouma
2008-01-01
A concept commonly used by both teachers and students is the term "chemical." Many students and teachers think of chemicals as artificial, poisonous, and dangerous. The purpose of the study was to investigate science teachers' ideas about "chemicals," along with their awareness of students' alternative conceptions and teaching practices that…
Efficient concepts for large erectable space structures
NASA Technical Reports Server (NTRS)
Card, M. F.; Bush, H. G.; Heard, W. L., Jr.; Mikulas, M. M., Jr.
1978-01-01
The status of Langley Research Center development of the nestable column concept is reviewed including results of member and truss component tests, and planned assembly studies. In addition, more recent studies of alternative member concepts are presented. Preliminary results on relative efficiency of several types of truss-type columns are compared and future test plans discussed.
ERIC Educational Resources Information Center
Schmidt, Hans-Jurgen; Baumgartner, Tim; Eybe, Holger
2003-01-01
Investigates secondary school students' concepts of isotopes and allotropes and how the concepts are linked to the Periodic Table of Elements (PTE). Questions senior high school students with multiple choice items and interviews. Shows that students actively tried to make sense of what they had experienced. (KHR)
Exploring High School Students' Perceptions of Solar Energy and Solar Cells
ERIC Educational Resources Information Center
Kishore, Padmini; Kisiel, James
2013-01-01
Although studies examining student understanding of key concepts are common throughout the science education literature, few have examined science concepts linked to conservation or environmental issues such as global warming and alternative energy. How students make sense of these complex concepts has the potential to influence their role as…
Turkish Prospective Chemistry Teachers' Alternative Conceptions about Acids and Bases
ERIC Educational Resources Information Center
Boz, Yezdan
2009-01-01
The purpose of this study was to obtain prospective chemistry teachers' conceptions about acids and bases concepts. Thirty-eight prospective chemistry teachers were the participants. Data were collected by means of an open-ended questionnaire and semi-structured interviews. Analysis of data indicated that most prospective teachers did not have…
Structural analysis of a bolted joint concept for the space shuttle's solid rocket motor casing
NASA Technical Reports Server (NTRS)
Lindell, Michael C.; Stalnaker, Winifred A.
1987-01-01
The Space Shuttle Challenger accident is thought to have been caused by the failure of one of the tang-clevis joints joining together the casing segments of the Solid Rocket Motors (SRM). Excessive displacement between the tang and clevis, possibly unseating the O-ring seals, may have initiated the resulting accident. An effort was made at NASA Langley Research Center to design an alternative concept for mating the casing segments. A bolted flange joint concept was designed and analyzed to determine if the concept would effectively maintain a seal while minimizing joint weight and controlling stress levels. It is shown that under the loading conditions analyzed the seal area of the joint remains seated. The only potential stress problem is a stress concentration in the flange at the edge of the bolt hole, which is highly localized. While heavier than the existing joint, this concept does have some advantages making the bolted joint an attractive alternative.
NASA Technical Reports Server (NTRS)
Howard, Robert L., Jr.
2016-01-01
The Evolvable Mars Campaign is developing concepts for human missions to the surface of Mars. These missions are round-trip expeditions, thereby requiring crew launch via a Mars Ascent Vehicle (MAV). A study to identify the smallest possible pressurized cabin for this mission has developed a conceptual vehicle referred to as the minimal MAV cabin. The origin of this concept will be discussed as well as its initial concept definition. This will lead to a description of possible configurations to integrate the minimal MAV cabin with ascent vehicle engines and propellant tanks. Limitations of this concept will be discussed, in particular those that argue against the use of the minimal MAV cabin to perform the MAV mission. However, several potential alternative uses for the cabin are identified. Finally, recommended forward work will be discussed, including current work in progress to develop a full scale mockup and conduct usability evaluations.
An alternative resource sharing scheme for land mobile satellite services
NASA Technical Reports Server (NTRS)
Yan, Tsun-Yee; Sue, Miles K.
1990-01-01
A preliminary comparison between the two competing channelization concepts for the Land Mobile Satellite Services (LMSS), namely frequency division (FD) and code division (CD), is presented. Both random access and demand-assigned approaches are considered under these concepts. The CD concept is compared with the traditional FD concept based on the system consideration and a projected traffic model. It is shown that CD is not particularly attractive for the first generation Mobile Satellite Services because of the spectral occupancy of the network bandwidth. However, the CD concept is a viable alternative for future systems such as the personal access satellite system (PASS) in the Ka-band spectrum where spectral efficiency is not of prime concern. The effects of power robbing and voice activity factor are incorporated. It was shown that the traditional rule of thumb of dividing the number of raw channels by the voice activity factor to obtain the effective number of channels is only valid asymptotically as the aggregated traffic approaches infinity.
An alternative resource sharing scheme for land mobile satellite services
NASA Astrophysics Data System (ADS)
Yan, Tsun-Yee; Sue, Miles K.
A preliminary comparison between the two competing channelization concepts for the Land Mobile Satellite Services (LMSS), namely frequency division (FD) and code division (CD), is presented. Both random access and demand-assigned approaches are considered under these concepts. The CD concept is compared with the traditional FD concept based on the system consideration and a projected traffic model. It is shown that CD is not particularly attractive for the first generation Mobile Satellite Services because of the spectral occupancy of the network bandwidth. However, the CD concept is a viable alternative for future systems such as the personal access satellite system (PASS) in the Ka-band spectrum where spectral efficiency is not of prime concern. The effects of power robbing and voice activity factor are incorporated. It was shown that the traditional rule of thumb of dividing the number of raw channels by the voice activity factor to obtain the effective number of channels is only valid asymptotically as the aggregated traffic approaches infinity.
NASA Technical Reports Server (NTRS)
1983-01-01
Mission scenario analysis and architectural concepts, alternative systems concepts, mission operations and architectural development, architectural analysis trades, evolution, configuration, and technology development are assessed.
ERIC Educational Resources Information Center
Michelson, Elana; Mandell, Alan
2004-01-01
For over thirty years, portfolios have been used to help adult learners gain recognition for their prior learning and take greater control of their educational experiences. The portfolio has become a distinctive means of assessing such learning, serving as a meaningful alternative to conventional papers and standardized testing. This book provides…
HEPA filter dissolution process
Brewer, K.N.; Murphy, J.A.
1994-02-22
A process is described for dissolution of spent high efficiency particulate air (HEPA) filters and then combining the complexed filter solution with other radioactive wastes prior to calcining the mixed and blended waste feed. The process is an alternate to a prior method of acid leaching the spent filters which is an inefficient method of treating spent HEPA filters for disposal. 4 figures.
Shah, Abhik; Woolf, Peter
2009-01-01
Summary In this paper, we introduce pebl, a Python library and application for learning Bayesian network structure from data and prior knowledge that provides features unmatched by alternative software packages: the ability to use interventional data, flexible specification of structural priors, modeling with hidden variables and exploitation of parallel processing. PMID:20161541
Sexual Deviance among Male College Students: Prior Deviance as an Explanation
ERIC Educational Resources Information Center
Jackson, Arrick; Veneziano, Louis; Riggen, Katherine
2004-01-01
Much research on sexual deviance on university and college campuses is limited by its narrow focus on group affiliation and leads to much speculation and conjecture. This article suggests that an alternative explanation is more suitable for explaining such an important and complex problem on college campuses. It argues that prior deviance serves…
Serial Learning in Rats: A Test of Three Hypotheses
ERIC Educational Resources Information Center
Capaldi, E. J.; Miller, Ronald Mellado
2004-01-01
Findings obtained by providing rats with a single fixed series of events, A-B-C-..., often are equally compatible with three alternative serial learning interpretations: that the signal for items is (A) their position in the series (position view), (B) the prior item of the series (chaining view), and (C) one, two, or more prior items of the…
Alternative evaluation of innovations’ effectiveness in mechanical engineering
NASA Astrophysics Data System (ADS)
Puryaev, A. S.
2017-09-01
The aim of present work is approbation of the developed technique for assessing innovations’ effectiveness. We demonstrate an alternative assessment of innovations’ effectiveness (innovation projects) in mechanical engineering on illustrative example. It is proposed as an alternative to the traditional method technique based on the value concept and the method of “Cash flow”.
Evaluation of laminar flow control system concepts for subsonic commercial transport aircraft
NASA Technical Reports Server (NTRS)
1980-01-01
A study was conducted to evaluate alternatives in the design of laminar flow control (LFC) subsonic commercial transport aircraft for operation in the 1980's period. Analyses were conducted to select mission parameters and define optimum aircraft configurational parameters for the selected mission, defined by a passenger payload of 400 and a design range of 12,038 km (6500 n mi). The baseline aircraft developed for this mission was used as a vehicle for the evaluation and development of alternative LFC system concepts. Alternatives were evaluated in the areas of aerodynamics structures, materials, LFC systems, leading-edge region cleaning and integration of auxiliary systems. Based on these evaluations, concept in each area were selected for further development and testing and ultimate incorporation in the final study aircraft. Relative to a similarly-optimized advanced technology turbulent transport, the final LFC configuration is approximately equal in direct operating cost but provides decreases of 8.2% in gross weight and 21.7% in fuel consumption.
An Alternative to Mapping a Word onto a Concept in Language Acquisition: Pragmatic Frames
Rohlfing, Katharina J.; Wrede, Britta; Vollmer, Anna-Lisa; Oudeyer, Pierre-Yves
2016-01-01
The classic mapping metaphor posits that children learn a word by mapping it onto a concept of an object or event. However, we believe that a mapping metaphor cannot account for word learning, because even though children focus attention on objects, they do not necessarily remember the connection between the word and the referent unless it is framed pragmatically, that is, within a task. Our theoretical paper proposes an alternative mechanism for word learning. Our main premise is that word learning occurs as children accomplish a goal in cooperation with a partner. We follow Bruner’s (1983) idea and further specify pragmatic frames as the learning units that drive language acquisition and cognitive development. These units consist of a sequence of actions and verbal behaviors that are co-constructed with a partner to achieve a joint goal. We elaborate on this alternative, offer some initial parametrizations of the concept, and embed it in current language learning approaches. PMID:27148105
Regulating Accuracy on University Tests with the Plurality Option
ERIC Educational Resources Information Center
Higham, Philip A.
2013-01-01
A single experiment is reported in which introductory psychology students were administered a multiple-choice test on psychology with either 4 (n = 78) or 5 alternatives (n = 92) prior to any lectures being delivered. Two answers were generated for each question: a small answer consisting of their favorite alternative, and a large answer…
Alternative Fuels Data Center: State Alternative Fuel and Advanced Vehicle
2017, the number of new state-level legislative, executive, private, and utility activities related to 2016 (54 total), but in line with previous years. The analysis below provides detail on trends in new (PEVs). Also consistent with recent prior years, new utility and private incentives primarily addressed
ERIC Educational Resources Information Center
Satake, Eiki; Amato, Philip P.
2008-01-01
This paper presents an alternative version of formulas of conditional probabilities and Bayes' rule that demonstrate how the truth table of elementary mathematical logic applies to the derivations of the conditional probabilities of various complex, compound statements. This new approach is used to calculate the prior and posterior probabilities…
Experience-Based and On-Line Categorization of Objects in Early Infancy
ERIC Educational Resources Information Center
Bornstein, Marc H.; Mash, Clay
2010-01-01
What processes do infants employ in categorizing? Infants might categorize on line as they encounter category-related entities; alternatively, infants might depend on prior experience with entities in formulating categories. These alternatives were tested in forty-four 5-month-olds. Infants who were familiarized in the laboratory with a category…
Descriptive Profile and Survey of Alternatively Certified Texas Music Educators
ERIC Educational Resources Information Center
Dye, Christopher K.
2018-01-01
The purpose of the study was to examine the features of Texas's Alternative Route to Certification (ARC) programs in music education, the demographics and prior experiences of program completers, and the employment of ARC completers in K-12 public schools. Data were collected from the State Board of Educator Certification about demographics and…
NASA Technical Reports Server (NTRS)
Horlitz, Krista L.; O'Leary, Ann
1993-01-01
The prolonged-inspection technique has been used to demonstrate effects of satiation on the perception of ambiguous figures. We propose that the inspection phase, in which subjects view an unambiguous version of the stimulus prior to observing the ambiguous figure, does not create neural fatigue but rather provides a context in which the alternative percept is apprehended and gains perceptual strength through processes such as imagination or memory. The consequent availability of the alternative organization drives the perceptual phenomena that have been thought to reflect satiation. In Experiment 1, we demonstrated that (1) preexperimental exposure to the target figures and (2) allocation of attention to the inspection figures were both necessary in order to obtain results similar to those predicted by the satiation model. In Experiment 2, we obtained similar results, finding that effects of prior inspection were greater the greater the amount and availability of information regarding the alternative percept during the inspection phase. Subjects who generated visual images of the noninspected alternative during inspection yielded results comparable to those from subjects to whom both versions were presented visually.
HSI top-down requirements analysis for ship manpower reduction
NASA Astrophysics Data System (ADS)
Malone, Thomas B.; Bost, J. R.
2000-11-01
U.S. Navy ship acquisition programs such as DD 21 and CVNX are increasingly relying on top down requirements analysis (TDRA) to define and assess design approaches for workload and manpower reduction, and for ensuring required levels of human performance, reliability, safety, and quality of life at sea. The human systems integration (HSI) approach to TDRA begins with a function analysis which identifies the functions derived from the requirements in the Operational Requirements Document (ORD). The function analysis serves as the function baseline for the ship, and also supports the definition of RDT&E and Total Ownership Cost requirements. A mission analysis is then conducted to identify mission scenarios, again based on requirements in the ORD, and the Design Reference Mission (DRM). This is followed by a mission/function analysis which establishes the function requirements to successfully perform the ship's missions. Function requirements of major importance for HSI are information, performance, decision, and support requirements associated with each function. An allocation of functions defines the roles of humans and automation in performing the functions associated with a mission. Alternate design concepts, based on function allocation strategies, are then described, and task networks associated with the concepts are developed. Task network simulations are conducted to assess workloads and human performance capabilities associated with alternate concepts. An assessment of the affordability and risk associated with alternate concepts is performed, and manning estimates are developed for feasible design concepts.
ERIC Educational Resources Information Center
Croft, Michael; de Berg, Kevin
2014-01-01
This paper selects six key alternative conceptions identified in the literature on student understandings of chemical bonding and illustrates how a historical analysis and a textbook analysis can inform these conceptions and lead to recommendations for improving the teaching and learning of chemical bonding at the secondary school level. The…
Student Conceptions of Ionic Bonding: Patterns of thinking across three European contexts
NASA Astrophysics Data System (ADS)
Taber, Keith S.; Tsaparlis, Georgios; Nakiboğlu, Canan
2012-12-01
Previous research has reported that students commonly develop alternative conceptions in the core topic of chemical bonding. Research in England has reported that students there commonly demonstrate an alternative 'molecular' conceptual framework for thinking about ionic bonding: in terms of the formation of molecule-like ions pairs through electron transfer, which are internally bonded, but not bonded to other ions. The present study reports the use of translated versions of a diagnostic instrument to elicit the conceptions of bonding in NaCl (commonly used as the teaching example of an ionic compound) from two samples of students setting out on university courses in Greece and Turkey. The study reports that students in these two contexts displayed high levels of support for statements based upon the alternative conceptual framework identified in the English context. Students commonly develop similar alternative conceptions of ionic bonding in these three different educational contexts. The study also found some quite large differences in the specific response patterns across these three contexts, some of which could reflect specific features of the different curriculum contexts. The study reinforces the cross-national nature of the challenge of effectively teaching the abstract models of chemistry at the submicroscopic level. It also provides intriguing suggestions that a close study of the interactions between specific curriculum contexts and specific patterns in students' thinking offers much potential for identifying particular aspects of subject pedagogy that either support or impede the learning of accepted scientific models.
"She Has to Drink Blood of the Snake": Culture and Prior Knowledge in Science|Health Education
ERIC Educational Resources Information Center
Bricker, Leah A.; Reeve, Suzanne; Bell, Philip
2014-01-01
In this analysis, we argue that science education should attend more deeply to youths' cultural resources and practices (e.g. material, social, and intellectual). Inherent in our argument is a call for revisiting conceptions of "prior knowledge" to theorize how people make sense of the complex ecologies of experience, ideas, and cultural…
ERIC Educational Resources Information Center
Pouget, Mireille; Osborne, Michael
2004-01-01
This article stems from the study of the process and application of Accreditation of Prior Experiential Learning (APEL) in the French higher education system, in France referred to as VAP (Validation des Acquis Professionnels ). The paper seeks to review not only the context in which the concepts underpinning VAP in France have developed, but also…
ERIC Educational Resources Information Center
Noll, Jennifer; Hancock, Stacey
2015-01-01
This research investigates what students' use of statistical language can tell us about their conceptions of distribution and sampling in relation to informal inference. Prior research documents students' challenges in understanding ideas of distribution and sampling as tools for making informal statistical inferences. We know that these…
Hannah's Prior Knowledge about Chemicals: A Case Study of One Fourth-Grade Child
ERIC Educational Resources Information Center
Bretz, Stacey Lowery; Emenike, Mary Elizabeth
2012-01-01
Chemical principles are taught in elementary education across much of the United States because the "National Science Education Standards" include concepts about the nature of matter, states of matter, and changes in matter among other science concepts within the first to fifth grade levels. "Chemicals" is a word related to the nature of matter…
ERIC Educational Resources Information Center
Rau, Martina A.
2017-01-01
STEM instruction often uses visual representations. To benefit from these, students need to understand how representations show domain-relevant concepts. Yet, this is difficult for students. Prior research shows that physical representations (objects that students manipulate by hand) and virtual representations (objects on a computer screen that…
ERIC Educational Resources Information Center
Waight, Noemi; Gillmeister, Kristina
2014-01-01
This study examined teachers' and students' initial conceptions of computer-based models--Flash and NetLogo models--and documented how teachers and students reconciled notions of multiple representations featuring macroscopic, submicroscopic and symbolic representations prior to actual intervention in eight high school chemistry…
ERIC Educational Resources Information Center
Strouse, Gabrielle A.; Ganea, Patricia A.
2016-01-01
Research Findings: Prior research indicates that shared book reading is an effective method for teaching biological concepts to young children. Adult questioning during reading enhances children's comprehension. We investigated whether adult prompting during the reading of an electronic book enhanced children's understanding of a biological…
Design and fabrication of a four-man capacity urine wick evaporator system
NASA Technical Reports Server (NTRS)
1979-01-01
The integrated system was tested to determine the performance characteristics and limitations of the dual catalyst concept. The primary objective of the dual catalyst concept is to remove ammonia and other noxious substances in the gas phase and thereby eliminate the need for and current practice of chemically or electrochemically pretreating urine prior to distillation.
NASA Technical Reports Server (NTRS)
Merino, F.; Oneill, R. F.
1980-01-01
The Cryogenic Fluid Management Experiment (CFME) was analyzed to assess the feasibility and advisability of deleting the vapor cooled shield (VCS) from the baseline CFME insulation and pressure control system. Two alternate concepts of CFME insulation and pressure control, neither of which incorporated the VCS, were investigated. The first concept employed a thermodynamic vent system (TVS) to throttle the flow through an internal wall mounted heat exchanger (HX) within the pressure vessel to decrease boiloff and pressure rise rate, while the second concept utilized a TVS without an internal heat exchanger. Only the first concept was viable. Its performance was assessed for a seven day mission and found to be satisfactory. It was also concluded that VCS development costs would be greater than for an internal HX installation. Based upon the above comparisons, the HX was recommended as a replacement for the VCS.
Integrated digital/electric aircraft concepts study
NASA Technical Reports Server (NTRS)
Cronin, M. J.; Hays, A. P.; Green, F. B.; Radovcich, N. A.; Helsley, C. W.; Rutchik, W. L.
1985-01-01
The integrated digital/electrical aircraft (IDEA) is an aircraft concept which employs all electric secondary power systems and advanced digital flight control systems. After trade analysis, preferred systems were applied to the baseline configuration. An additional configuration, the alternate IDEA, was also considered. For this concept the design ground rules were relaxed in order to quantify additional synergistic benefits. It was proposed that an IDEA configuration and technical risks associated with the IDEA systems concepts be defined and the research and development required activities to reduce these risks be identified. The selected subsystems include: power generation, power distribution, actuators, environmental control system and flight controls systems. When the aircraft was resized, block fuel was predicted to decrease by 11.3 percent, with 7.9 percent decrease in direct operating cost. The alternate IDEA shows a further 3.4 percent reduction in block fuel and 3.1 percent reduction in direct operating cost.
NASA Technical Reports Server (NTRS)
Larimer, Stanley J.; Lisec, Thomas R.; Spiessbach, Andrew J.
1989-01-01
Under a contract with NASA's Jet Propulsion Laboratory, Martin Marietta has developed several alternative rover concepts for unmanned exploration of the planet Mars. One of those concepts, the 'Walking Beam', is the subject of this paper. This concept was developed with the goal of achieving many of the capabilities of more sophisticated articulated-leg walkers with a much simpler, more robust, less computationally demanding and more power efficient design. It consists of two large-base tripods nested one within the other which alternately translate with respect to each other along a 5-meter beam to propel the vehicle. The semiautonomous navigation system relies on terrain geometry sensors and tacticle feedback from each foot to autonomously select a path which avoids hazards along a route designated from earth. Both mobility and navigation features of this concept are discussed including a top-level description of the vehicle's physical characteristics, deployment strategy, mobility elements, sensor suite, theory of operation, navigation and control processes, and estimated performance.
Piloted simulation study of two tilt-wing control concepts
NASA Technical Reports Server (NTRS)
Birckelbaw, Lourdes G.; Corliss, Lloyd D.
1994-01-01
A two-phase piloted simulation study was conducted to investigate alternative wing and flap controls for tilt-wing aircraft. The initial phase of the study compared the flying qualities of both a conventional (programmed) flap and an innovative geared flap. The second phase of the study introduced an alternate method of pilot control for the geared flap and further studied the flying qualities of the programmed flap, and two geared flap configurations. In general, the pilot rating showed little variation between the programmed flap and the geared flap control concepts. Some differences between the two concepts were noticed and are discussed in this paper. The addition of pitch attitude stabilization in the second phase of the study greatly enhanced the aircraft flying qualities. This paper describes the simulated tilt-wing aircraft and the flap control concepts and presents the results of both phases of the simulation study.
No-waiting dentine self-etch concept-Merit or hype.
Huang, Xue-Qing; Pucci, César R; Luo, Tao; Breschi, Lorenzo; Pashley, David H; Niu, Li-Na; Tay, Franklin R
2017-07-01
A recently-launched universal adhesive, G-Premio Bond, provides clinicians with the alternative to use the self-etch technique for bonding to dentine without waiting for the adhesive to interact with the bonding substrate (no-waiting self-etch; Japanese brochure), or after leaving the adhesive undisturbed for 10s (10-s self-etch; international brochure). The present study was performed to examine in vitro performance of this new universal adhesive bonded to human coronal dentine using the two alternative self-etch modes. One hundred and ten specimens were bonded using two self-etch application modes and examined with or without thermomechanical cycling (10,000 thermal cycles and 240,000 mechanical cycles) to simulate one year of intraoral functioning. The bonded specimens were sectioned for microtensile bond testing, ultrastructural and nanoleakage examination using transmission electron microscopy. Changes in the composition of mineralised dentine after adhesive application were examined using Fourier transform infrared spectroscopy. Both reduced application time and thermomechanical cycling resulted in significantly lower bond strengths, thinner hybrid layers, and significantly more extensive nanoleakage after thermomechanical cycling. Using the conventional 10-s application time improved bonding performance when compared with the no-waiting self-etch technique. Nevertheless, nanoleakage was generally extensive under all testing parameters employed for examining the adhesive. Although sufficient bond strength to dentine may be achieved using the present universal adhesive in the no-waiting self-etch mode that does not require clinicians to wait prior to polymerisation of the adhesive, this self-etch concept requires further technological refinement before it can be recommended as a clinical technique. Although the surge for cutting application time to increase user friendliness remains the most frequently sought conduit for advancement of dentine bonding technology, the use of the present universal adhesive in the no-waiting self-etch mode may not represent the best use of the adhesive. Published by Elsevier Ltd.
NASA Astrophysics Data System (ADS)
Sampath Kumar, Bharath
The purpose of this study is to examine the role of partnering visualization tool such as simulation towards development of student's concrete conceptual understanding of chemical equilibrium. Students find chemistry concepts abstract, especially at the microscopic level. Chemical equilibrium is one such topic. While research studies have explored effectiveness of low tech instructional strategies such as analogies, jigsaw, cooperative learning, and using modeling blocks, fewer studies have explored the use of visualization tool such as simulations in the context of dynamic chemical equilibrium. Research studies have identified key reasons behind misconceptions such as lack of systematic understanding of foundational chemistry concepts, failure to recognize the system is dynamic, solving numerical problems on chemical equilibrium in an algorithmic fashion, erroneous application Le Chatelier's principle (LCP) etc. Kress et al. (2001) suggested that external representation in the form of visualization is more than a tool for learning, because it enables learners to make meanings or express their ideas which cannot be readily done so through a verbal representation alone. Mixed method study design was used towards data collection. The qualitative portion of the study is aimed towards understanding the change in student's mental model before and after the intervention. A quantitative instrument was developed based on common areas of misconceptions identified by research studies. A pilot study was conducted prior to the actual study to obtain feedback from students on the quantitative instrument and the simulation. Participants for the pilot study were sampled from a single general chemistry class. Following the pilot study, the research study was conducted with a total of 27 students (N=15 in experimental group and N=12 in control group). Prior to participating in the study, students have completed their midterm test on the topic of chemical equilibrium. Qualitative interviews pre and post revealed students' mental model or thought process towards chemical equilibrium. Simulations used in the study were developed using the SCRATCH software platform. In order to test the effect of visualization tool on students' conceptual understanding of chemical equilibrium, an ANCOVA analysis was conducted. Results from a one-factor ANCOVA showed posttest scores were significantly higher for the experimental group (Mpostadj. = 7.27 SDpost = 1.387) relative to the control group (Mpostadj. = 2.67, SDpost = 1.371) after adjusting for pretest scores, F (1,24) = 71.82, MSE = 1.497, p = 0.03, eta 2p = 0.75, d = 3.33. Cohen's d was converted to an attenuated effect size d* using the procedure outlined in Thompson (2006). The adjusted (for pretest scores) group mean difference estimate without measure error correction for the posttest scores and the pretest scores was 4.2 with a Cohen's d = 3.04. An alternate approach reported in Cho and Preacher (2015) was used to determine effect size. The adjusted (for pretest scores) group mean difference estimate with measurement error correction only for the posttest scores (but not with measurement error correction for the pretest scores) was 4.99 with a Cohen's d = 3.61. Finally, the adjusted (for pretest scores) group mean difference estimate with measurement error correction for both pretest and posttest scores was 4.23 with a Cohen's d = 3.07. From a quantitative perspective, these effect size indicate a strong relationship between the experimental intervention provided and students' conceptual understanding of chemical equilibrium concepts. That is, those students who received the experimental intervention had exceptionally higher. KEYWORDS: Chemical Equilibrium, Visualization, Alternate Conceptions, Ontological Shift. Simulations.
NASA Astrophysics Data System (ADS)
Vosniadou, Stella; Skopeliti, Irini
2017-10-01
The present research tested the hypothesis that the reading of science text can create new misconceptions in students with incongruent prior knowledge, and that these new misconceptions will be similar to the fragmented and synthetic conceptions obtained in prior developmental research. Ninety-nine third- and fifth-grade children read and recalled one of two texts that provided scientific or phenomenal explanations of the day/night cycle. All the participants gave explanations of the phenomenon in question prior to reading one of the texts and after they read it. The results showed that the participants who provided explanations of the day/night cycle at pretest incongruent with the scientific explanation recalled less information and generated more invalid inferences. An analysis of the participants' posttest explanations indicated that these readers formed new misconceptions similar to the fragmented and synthetic conceptions obtained in developmental research. The implications of the above for text comprehension and science education research are discussed.
Roll splitting as an alternative intermediate process for wood fuel
Paul E. Barnett; Donald L. Sirois
1985-01-01
In an effort to develop mobile equipment for harvesting and processing woody biomass from power line rights-of-way and precommerial thinnings, numerous alternative concepts were evaluated by Tennessee Valley Authority's Timber Harvesting Project.
Identifying Atomic Structure as a Threshold Concept: Student Mental Models and Troublesomeness
ERIC Educational Resources Information Center
Park, Eun Jung; Light, Gregory
2009-01-01
Atomic theory or the nature of matter is a principal concept in science and science education. This has, however, been complicated by the difficulty students have in learning the concept and the subsequent construction of many alternative models. To understand better the conceptual barriers to learning atomic structure, this study explores the…
An Alternative View of Forest Sampling
Francis A. Roesch; Edwin J. Green; Charles T. Scott
1993-01-01
A generalized concept is presented for all of the commonly used methods of forest sampling. The concept views the forest as a two-dimensional picture which is cut up into pieces like a jigsaw puzzle, with the pieces defined by the individual selection probabilities of the trees in the forest. This concept results in a finite number of independently selected sample...
Defense Science and Technology Strategy
1994-09-01
I 3 IV. The Science and Technology Program .................... 15 Advanced Concept Technology Demomstrations...product and process concepts that pcrmit us to tailor, modify, and optimize the manufactUriiig process; develop sensors a-t i~a Mcrials that will detect...It can be used during concept formulations to expand the range of technical, operational, and system alternatives evaluated. The technology can
ERIC Educational Resources Information Center
Griffiths, Alan Keith; Preston, Kirk R.
An understanding of the concepts of atoms and molecules is fundamental to the learning of chemistry. Any misconceptions and alternative conceptions related to these concepts which students harbor will impede much further learning. This paper identifies misconceptions related to the fundamental characteristics of atoms and molecules which Grade 12…
A Teaching Sequence for Learning the Concept of Chemical Equilibrium in Secondary School Education
ERIC Educational Resources Information Center
Ghirardi, Marco; Marchetti, Fabio; Pettinari, Claudio; Regis, Alberto; Roletto, Ezio
2014-01-01
A novel didactic sequence is proposed for the teaching of chemical equilibrium. This teaching sequence takes into account the historical and epistemological evolution of the concept, the alternative conceptions and learning difficulties highlighted by teaching science and research in education, and the need to focus on both the students'…
Federal Register 2010, 2011, 2012, 2013, 2014
2010-11-22
... Services Delivery Architecture Recommendations are included in the TOR deliverables. The Concept of Use for... operating picture for evolving global ATM concepts. The AIS and MET Services Delivery Architecture... provides recommended alternatives for AIS and MET data delivery architectures. The Concept of Use and...
Concept Maps: An Alternative Methodology to Assess Young Children
ERIC Educational Resources Information Center
Atiles, Julia T.; Dominique-Maikell, Nikole; McKean, Kathleen
2014-01-01
The authors investigated the utility and efficacy of using concepts maps as a research tool to assess young children. Pre- and post- concept maps have been used as an assessment and evaluation tool with teachers and with older students, typically children who can read and write; this article summarizes an investigation into the utility of using…
System status display evaluation
NASA Technical Reports Server (NTRS)
Summers, Leland G.
1988-01-01
The System Status Display is an electronic display system which provides the crew with an enhanced capability for monitoring and managing the aircraft systems. A flight simulation in a fixed base cockpit simulator was used to evaluate alternative design concepts for this display system. The alternative concepts included pictorial versus alphanumeric text formats, multifunction versus dedicated controls, and integration of the procedures with the system status information versus paper checklists. Twelve pilots manually flew approach patterns with the different concepts. System malfunctions occurred which required the pilots to respond to the alert by reconfiguring the system. The pictorial display, the multifunction control interfaces collocated with the system display, and the procedures integrated with the status information all had shorter event processing times and lower subjective workloads.
NASA Technical Reports Server (NTRS)
LaBel, Kenneth A.; Sampson, Michael J.
2017-01-01
As the space business rapidly evolves to accommodate a lower cost model of development and operation via concepts such as commercial space and small spacecraft (aka, CubeSats and swarms), traditional EEE parts screening and qualification methods are being scrutinized under a risk-reward trade space. In this presentation, two basic concepts will be discussed: (1) The movement from complete risk aversion EEE parts methods to managing and/or accepting risk via alternate approaches; and, (2) A discussion of emerging assurance methods to reduce overdesign as well emerging model based mission assurance (MBMA) concepts. center dot Example scenarios will be described as well as consideration for trading traditional versus alternate methods.
Investigating the Effectiveness of Teaching Methods Based on a Four-Step Constructivist Strategy
NASA Astrophysics Data System (ADS)
Çalik, Muammer; Ayas, Alipaşa; Coll, Richard K.
2010-02-01
This paper reports on an investigation of the effectiveness an intervention using several different methods for teaching solution chemistry. The teaching strategy comprised a four-step approach derived from a constructivist view of learning. A sample consisting of 44 students (18 boys and 26 girls) was selected purposively from two different Grade 9 classes in the city of Trabzon, Turkey. Data collection employed a purpose-designed `solution chemistry concept test', consisting of 17 items, with the quantitative data from the survey supported by qualitative interview data. The findings suggest that using different methods embedded within the four-step constructivist-based teaching strategy enables students to refute some alternative conceptions, but does not completely eliminate student alternative conceptions for solution chemistry.
Assessment of cockpit interface concepts for data link retrofit
NASA Technical Reports Server (NTRS)
Mccauley, Hugh W.; Miles, William L.; Dwyer, John P.; Erickson, Jeffery B.
1992-01-01
The problem is examined of retrofitting older generation aircraft with data link capability. The approach taken analyzes requirements for the cockpit interface, based on review of prior research and opinions obtained from subject matter experts. With this background, essential functions and constraints for a retrofit installation are defined. After an assessment of the technology available to meet the functions and constraints, candidate design concepts are developed. The most promising design concept is described in detail. Finally, needs for further research and development are identified.
Preliminary Modeling of Accident Tolerant Fuel Concepts under Accident Conditions
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gamble, Kyle A.; Hales, Jason D.
2016-12-01
The catastrophic events that occurred at the Fukushima-Daiichi nuclear power plant in 2011 have led to widespread interest in research of alternative fuels and claddings that are proposed to be accident tolerant. Thus, the United States Department of Energy through its NEAMS (Nuclear Energy Advanced Modeling and Simulation) program has funded an Accident Tolerant Fuel (ATF) High Impact Problem (HIP). The ATF HIP is funded for a three-year period. The purpose of the HIP is to perform research into two potential accident tolerant concepts and provide an in-depth report to the Advanced Fuels Campaign (AFC) describing the behavior of themore » concepts, both of which are being considered for inclusion in a lead test assembly scheduled for placement into a commercial reactor in 2022. The initial focus of the HIP is on uranium silicide fuel and iron-chromium-aluminum (FeCrAl) alloy cladding. Utilizing the expertise of three national laboratory participants (INL, LANL, and ANL) a comprehensive mulitscale approach to modeling is being used including atomistic modeling, molecular dynamics, rate theory, phase-field, and fuel performance simulations. In this paper, we present simulations of two proposed accident tolerant fuel systems: U3Si2 fuel with Zircaloy-4 cladding, and UO2 fuel with FeCrAl cladding. The simulations investigate the fuel performance response of the proposed ATF systems under Loss of Coolant and Station Blackout conditions using the BISON code. Sensitivity analyses are completed using Sandia National Laboratories’ DAKOTA software to determine which input parameters (e.g., fuel specific heat) have the greatest influence on the output metrics of interest (e.g., fuel centerline temperature). Early results indicate that each concept has significant advantages as well as areas of concern. Further work is required prior to formulating the proposition report for the Advanced Fuels Campaign.« less
Inbal, Amir; Lemelman, Benjamin T; Millet, Eran; Greensmith, Andrew
2017-10-16
Auricular reconstruction is one of the most challenging procedures in plastic surgery. An adequate skin envelope is essential for cartilage framework coverage, yet few good options exist without additional surgery. We propose a novel method for minimally invasive tissue expansion, using hyaluronic acid (HA) filler to allow for single-stage ear reconstruction. To introduce the novel concept of HA filler for tissue expansion in ear reconstruction, and as an alternative to traditional expansion techniques. Macrolane is a large particle HA gel developed for large volume restoration. Expansion of the non-hair-bearing mastoid skin was performed in our clinic weekly or every other week. Final expansion was completed one week prior to reconstructive surgery. Tissue from one patient's expanded pocket was sent for histological analysis. Ten patients underwent single-stage auricular reconstruction with preoperative expansion. Injection sessions ranged from 7 to 13 (mean, 9.7). Mean injected volume per session was 2.03 mL per patient, for an average total of 19.8 mL (range, 14.5-30 mL). There were no major complications. One minor complication required removal of exposed wire from the antihelix in the office. Hematoxylin and eosin stain revealed similar histology to that seen with traditional expanders. This novel expansion technique using serial HA injections allowed for optimized skin coverage in single-stage ear reconstruction. The concept of tissue expansion using HA filler is a new frontier for research that may be applicable to other arenas of reconstruction. 4. © 2017 The American Society for Aesthetic Plastic Surgery, Inc. Reprints and permission: journals.permissions@oup.com
Spotting Books and Countries: New Approaches to Estimating and Conceptualizing Prior Intelligence
ERIC Educational Resources Information Center
Scott, Kirsten M.; de Wit, Isabella; Deary, Ian J.
2006-01-01
We aimed to design alternative estimates of pre-morbid/prior intelligence to the National Adult Reading Test (NART) and the Spot-the-Word (STW) in order to tap non-vocabulary based knowledge stores. The rationale for the development of the new tests was that more cognitively able individuals acquire and retain more "singular facts" from their…
Mediating Mental Models of Metals: Acknowledging the Priority of the Learner's Prior Learning
ERIC Educational Resources Information Center
Taber, Keith S.
2003-01-01
This paper describes the conceptualizations, or mental models, of the nature of the bonding and structure of metals of a group of U.K. college students. It is suggested that these mental models may be understood in terms of the students' prior learning about covalent and ionic bonding, and the prevalence of a common alternative conceptual…
ERIC Educational Resources Information Center
Harris, Judy
1999-01-01
Describes four models of recognition of prior learning (PL): (1) procrustean--PL is made to match predetermined standards; (2) learning and development--PL approximates implicit academic standards; (3) radical--subjective knowledge is recognized as an alternative to dominant forms; and (4) Trojan-horse--PL is seen as socially constructed and…
Beacon Collision Avoidance System (BCAS) Alternative Concepts for Determining Target Positions
DOT National Transportation Integrated Search
1978-09-01
The (Litchford) Beacon-based Collision Avoidance System concept requires the computation of target range and bearing relative to the BCAS aircraft. Techniques for determining target range and bearing under four different assumptions about the ground ...
Water conservation and reform of the prior appropriation doctrine in Colorado
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wescoat, J.L. Jr.
The prior appropriation doctrine has come under criticism for impeding both the efficient allocation of water and the adoption of water conservation improvements. Analysis of water rights statutes and case law revealed the following opportunities for evolutionary reform of the appropriation doctrine in Colorado: more precise definition of key property rights concepts (such as beneficial use, waste and duty of water); improved public administration (e.g., in record-keeping and analysis of water use patterns); and organizational adjustments to reduce transaction costs and strategic behavior. Integration of vested rights with the concept of maximum beneficial use will depend upon such creative adjustmentsmore » in public and private institutions for water management. 32 references, 3 figures, 4 tables.« less
Millimeter wave detection of nuclear radiation: an alternative detection mechanism.
Gopalsami, N; Chien, H T; Heifetz, A; Koehl, E R; Raptis, A C
2009-08-01
We present a nuclear radiation detection mechanism using millimeter waves as an alternative to conventional detection. It is based on the concept that nuclear radiation causes ionization of air and that if we place a dielectric material near the radiation source, it acts as a charge accumulator of the air ions. We have found that millimeter waves can interrogate the charge cloud on the dielectric material remotely. This concept was tested with a standoff millimeter wave system by monitoring the charge levels on a cardboard tube placed in an x-ray beam.
USDA-ARS?s Scientific Manuscript database
Phenylbutyrate (PB) is a drug used in urea cycle disorder patients to elicit alternative pathways for nitrogen disposal. However, PB decreases plasma branched chain amino acid (BCAA) concentrations and prior research suggests that PB may increase leucine oxidation, indicating increased protein degra...
1984-06-01
Establishing or changing priorities Program evaluation is economic analysis of ongoing actions to determine how best to improve an approved program...on an analysis as called for herein. When proposed actions are specifically directed by legislation or prior irrevocable management decisions which...continuing the present course of action , or inaction, may be a feasible alternative. The identification of alternative courses of action is an
Potable Water Quality Management Guidance Document
2007-09-01
with alternative disinfectants and/or oxidants that form fewer disinfection byproducts than chlorine, such as chloramines , UV, ozone and chlorine...Alternative Disinfection Strategies............................................................................ 37 5.2.5.1. Chloramines ... disinfectant contact time” ( T ) in minutes, i.e., “C” x “ T ”. If a public water system applies disinfectants at more than one point prior to the first customer
Code of Federal Regulations, 2010 CFR
2010-04-01
..., will beneficiaries for whom an employment plan was signed prior to implementation be covered under the Ticket to Work program payment provisions? 411.715 Section 411.715 Employees' Benefits SOCIAL SECURITY ADMINISTRATION THE TICKET TO WORK AND SELF-SUFFICIENCY PROGRAM The Ticket to Work Program and Alternate...
Krebs, Lynette D; Kirkland, Scott W; Chetram, Rajiv; Nikel, Taylor; Voaklander, Britt; Davidson, Alan; Holroyd, Bryn; Villa-Roel, Cristina; Crick, Katelynn; Couperthwaite, Stephanie; Alexiu, Chris; Cummings, Garnet; Rowe, Brian H
2017-04-01
ED visits have been rising year on year worldwide. It has been suggested that some of these visits could be avoided if low-acuity patients had better primary care access. This study explored patients' efforts to avoid ED presentation and alternative care sought prior to presentation. Consecutive adult patients presenting to three urban EDs in Edmonton, Canada, completed a questionnaire collecting demographics, actions attempted to avoid presentation and reasons for presentation. Survey data were cross-referenced to a minimal patient dataset containing ED and demographic information. A total of 1402 patients (66.5%) completed the survey. Although 89.3% of the patients felt that the ED was their best care option, the majority of patients (60.1%) sought alternative care or advice prior to presentation. Men, individuals who presented with injury only, and individuals with less than a high school education were all less likely to seek alternative care. Alternative care actions included visiting a physician (54.1%) or an alternative healthcare professional (eg, chiropractor, physiotherapist, etc; 21.2%), calling physician offices (47%) or the regional health information line (13%). Of those who called their physicians, the majority received advice to present to the ED (67.5%). Most low-acuity patients attempt to avoid ED presentation by seeking alternative care. This analysis identifies groups of individuals in the study region who are less likely to seek alternative care first and may benefit from targeted interventions/education. Other regions may wish to complete a similar profile to determine which patients are less likely to seek alternative care first. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.
Shiroff, Jennifer J; Gregoski, Mathew J
2017-06-01
Measurement of recessive carrier screening attitudes related to conception and pregnancy is necessary to determine current acceptance, and whether behavioral intervention strategies are needed in clinical practice. To evaluate quantitative survey instruments to measure patient attitudes regarding genetic carrier testing prior to conception and pregnancy databases examining patient attitudes regarding genetic screening prior to conception and pregnancy from 2003-2013 were searched yielding 344 articles; eight studies with eight instruments met criteria for inclusion. Data abstraction on theoretical framework, subjects, instrument description, scoring, method of measurement, reliability, validity, feasibility, level of evidence, and outcomes was completed. Reliability information was provided in five studies with an internal consistency of Cronbach's α >0.70. Information pertaining to validity was presented in three studies and included construct validity via factor analysis. Despite limited psychometric information, these questionnaires are self-administered and can be briefly completed, making them a feasible method of evaluation.
Study of a Wind Energy Conversion System in New Hampshire.
1981-08-01
Federal Jurisdiction Prior to PURPA ........ . 91 2) State Jurisdiction Prior to PURPA .... ....... 93 3) The Contemplated Effect of PURPA on the FERC’s...Jurisdictional Powers ..... ...... 94 (a) Definitions and Concepts of PURPA ... .. 95 (b) Analysis of Wheeling and Interconnection . 96 (i) FPA 9 210...Regarding Certain Interconnection and Wheeling ...... .. ........ 97 (c) PURPA § 210, Cogeneration and Small Power Production ...... ... ... .. 98 b
Biased predecisional processing of leading and nonleading alternatives.
Blanchard, Simon J; Carlson, Kurt A; Meloy, Margaret G
2014-03-01
When people obtain information about choice alternatives in a set one attribute at a time, they rapidly identify a leading alternative. Although previous research has established that people then distort incoming information, it is unclear whether distortion occurs through favoring of the leading alternative, disfavoring of the trailing alternative, or both. Prior examinations have not explored the predecisional treatment of the nonleading alternative (or alternatives) because they conceptualized distortion as a singular construct in binary choice and measured it using a relative item comparing the evaluation of both alternatives simultaneously. In this article, we introduce a measure of distortion at the level of the alternative, which allows for measuring whether predecisional distortion favors or disfavors every alternative being considered in choice sets of various sizes. We report that both proleader and antitrailer distortion occur and that the use of antitrailer processing differs between binary choices and multiple-options choices.
ERIC Educational Resources Information Center
Wong, Phoebe; Mak, Connie; Ng, Peggy M. L.; Zhao, Jessie
2017-01-01
This study explores the interrelationships between self-concept, motivation and academic and social experience among students from self-financing higher education institutions in Hong Kong. Although prior studies have investigated different aspects of self that drive various types of motivation in students' academic and social experience, most of…
ERIC Educational Resources Information Center
Kao, Chia-Pin; Chien, Hui-Min
2017-01-01
This study was conducted to explore the relationships between pre-school educators' conceptions of and approaches to learning by web-searching through Internet Self-efficacy. Based on data from 242 pre-school educators who had prior experience of participating in web-searching in Taiwan for path analyses, it was found in this study that…
ERIC Educational Resources Information Center
Hohensee, Charles
2014-01-01
The transfer of learning has been the subject of much scientific inquiry in the social sciences. However, mathematics education research has given little attention to a subclass called backward transfer, which is when learning about new concepts influences learners' ways of reasoning about previously encountered concepts. This study examined when…
ERIC Educational Resources Information Center
Tomaraa, Marina; Tselfes, Vassilis; Goucos, Dimitris
2017-01-01
During the last four decades, the results of a great deal of research have indicated that, prior to any formal instruction in physics, students hold scientifically incorrect ideas about physics concepts in general, and about the force and motion concepts in particular, the latter being considered central in science teaching. To these days,…
ERIC Educational Resources Information Center
Dethmers, Claer
Compared were the effects of an innovative and a traditional teaching approach on the achievement, self-concept, and sense of control scores of fifth and sixth grade children from lower class family backgrounds. Prior to treatment, the students in the two schools were comparable on economics deprivation, educational deprivation, achievement,…
Forms of Self-Concept in Gifted High School Students Enrolled in Heterogeneous Classes
ERIC Educational Resources Information Center
Villatte, Aude; Hugon, Mandarine; de Leonardis, Myriam
2011-01-01
Prior research has been devoted to understanding how to facilitate the integration of gifted young people (Intelligence Quotient, greater than or equal to 130) into classroom settings. This study investigated a typology of self-concept in gifted French high school students. Eighty-four participants, between the ages of 13 and 18 (mean age, 15.5;…
Conceptions over Time: Are Language and the Here-and-Now up to the Task?
ERIC Educational Resources Information Center
Hewson, Peter W.
2008-01-01
Is it possible to explain students' conceptions of natural phenomena purely in terms of the interactions between two people and the language they use during an interview? I argue that this hypothesis cannot be accepted on several grounds. First, contextual factors prior to the interview influence the course of its events, and that these in turn…
Improving Students' Understanding of Waves by Plotting a Displacement-Time Graph in Class
ERIC Educational Resources Information Center
Wei, Yajun
2012-01-01
The topic of waves is one that many high school physics students find difficult to understand. This is especially true when using some A-level textbooks used in the U.K., where the concept of waves is introduced prior to the concept of simple harmonic oscillations. One of the challenges my students encounter is understanding the difference between…
ERIC Educational Resources Information Center
Fuentealba, Claudio; Sánchez-Matamoros, Gloria; Badillo, Edelmira; Trigueros, María
2017-01-01
This study is part of a more extensive research project that addresses the understanding of the derivative concept in university students with prior instruction in differential calculus. In particular, we focus on the analysis of students' responses to a sequence of tasks that require a high level of understanding of the concept, and complement…
ERIC Educational Resources Information Center
Koc, Mustafa
2012-01-01
This study explored (a) pre-service teachers' perceptions of using concept mapping (CM) in one of their pedagogical courses, (b) the predictive power of such implementation in course achievement, and (c) the role of prior experience with CM, type of mapping, and gender on their perceptions and performances in CM and achievement. The subjects were…
Examining Student Conceptions of Covariation: A Focus on the Line of Best Fit
ERIC Educational Resources Information Center
Casey, Stephanie A.
2015-01-01
The purpose of this research study was to learn about students' conceptions concerning the line of best fit just prior to their introduction to the topic. Task-based interviews were conducted with thirty-three students, focused on five tasks that asked them to place the line of best fit on a scatterplot and explain their reasoning throughout the…
Understanding the relationship between student attitudes and student learning
NASA Astrophysics Data System (ADS)
Cahill, Michael J.; McDaniel, Mark A.; Frey, Regina F.; Hynes, K. Mairin; Repice, Michelle; Zhao, Jiuqing; Trousil, Rebecca
2018-02-01
Student attitudes, defined as the extent to which one holds expertlike beliefs about and approaches to physics, are a major research topic in physics education research. An implicit but rarely tested assumption underlying much of this research is that student attitudes play a significant part in student learning and performance. The current study directly tested this attitude-learning link by measuring the association between incoming attitudes (Colorado Learning Attitudes about Science Survey) and student learning during the semester after statistically controlling for the effects of prior knowledge [early-semester Force Concept Inventory (FCI) or Brief Electricity and Magnetism Assessment (BEMA)]. This study spanned four different courses and included two complementary measures of student knowledge: late-semester concept inventory scores (FCI or BEMA) and exam averages. In three of the four courses, after controlling for prior knowledge, attitudes significantly predicted both late-semester concept inventory scores and exam averages, but in all cases these attitudes explained only a small amount of variance in concept-inventory and exam scores. Results indicate that after accounting for students' incoming knowledge, attitudes may uniquely but modestly relate to how much students learn and how well they perform in the course.
ERIC Educational Resources Information Center
Lensmire, Timothy J.
2014-01-01
Background/Context: Increasingly, researchers and educators have argued that alternative conceptions of Whiteness and White racial identity are needed because current conceptions have undermined, rather than strengthened, our critical pedagogies with White people. Grounded in critical Whiteness studies, and drawing especially on the writings of…
48 CFR 34.005-1 - Competition.
Code of Federal Regulations, 2011 CFR
2011-10-01
..., throughout the acquisition process, promote full and open competition and sustain effective competition between alternative major system concepts and sources, as long as it is economically beneficial and... officer should time solicitation issuance and contract award to maintain continuity of concept development...
ERIC Educational Resources Information Center
Petersson, Gunilla
2005-01-01
This study describes how medical and nursing students develop their conceptions and understanding of science during 3 years of study at the academic level. The point of departure is the students' commonsense conceptions at the start of the undergraduate programme, which are seen as alternative ways of thinking to the more theoretical explanatory…
ERIC Educational Resources Information Center
Yakisan, Mehmet
2016-01-01
Biology that is a branch of science examining organisms in every aspect has a very wide content. Besides this wide content, there are abstract concepts in some subjects. Various alternative conceptions are determined in different education levels especially in abstract and microscopic biology subjects. The aim of this study is to determine the…
ERIC Educational Resources Information Center
Troncoso, Carlos; Lavalle, Andrea; Curia, Leopoldo; Daniele, Elaine; Chrobak, Ricardo
The present work has the purpose of showing the evolution of topics or mathematical concepts that are both relevant and with marked grades of abstraction. In this report is specifically described the utilization of metacognitive tools. These include concept maps, the Gowin heuristic vee, and the clinical interview. They are efficient in showing…
ERIC Educational Resources Information Center
Bramwell-Lalor, Sharon; Rainford, Marcia
2014-01-01
This paper reports on teachers' use of concept mapping as an alternative assessment strategy in advanced level biology classes and its effects on students' cognitive skills on selected biology concepts. Using a mixed methods approach, the study employed a pre-test/post-test quasi-experimental design involving 156 students and 8 teachers from…
ERIC Educational Resources Information Center
Unal, Suat; Calik, Muammer; Ayas, Alipasa; Coll, Richard K.
2006-01-01
The present paper presents a detailed thematic review of chemical bonding studies. To achieve this, a matrix is developed to summarize and present the findings by focusing on insights derived from the related studies. The matrix incorporates the following themes: needs, aims, methods of exploring students' conceptions, general knowledge claims,…
NASA Astrophysics Data System (ADS)
Rahayu, Sri; Treagust, David F.; Chandrasegaran, A. L.; Kita, Masakazu; Ibnu, Suhadi
2011-07-01
Background and purpose: This study investigated Indonesian and Japanese senior high-school students' understanding of electrochemistry concepts. Sample The questionnaire was administered to 244 Indonesian and 189 Japanese public senior high-school students. Design and methods An 18-item multiple-choice questionnaire relating to five conceptual categories (reactions occurring during electrolysis, differences between electrolytic and voltaic cells, movement of ions in voltaic cells, poles in voltaic cells, voltaic cell reactions) was administered. Results The findings of this study show that difficulties and alternative conceptions previously reported in the literature are held equally by students from a developing and developed country, Indonesian and Japan respectively. Conclusions Collectively, the findings suggest that students' understanding of electrochemistry concepts is relatively weak. Students from both samples shared common difficulties and displayed several alternative conceptions dealing with electrolysis, electricity flow, the voltaic cell and the electrode reactions. Not surprisingly, the students displayed limited consistency in understanding of the concepts in the five categories. This study has implications for teaching and learning, particularly in classroom discussions using models and computer animations in order to reinforce understanding at the sub-microscopic level.
Environment and Alternative Development.
ERIC Educational Resources Information Center
Kothari, Rajni
Stressing the global dimension to the adversary relationship between economic development and environmental conservation, this monograph examines the philosophical, historical, cultural, and ethnic underpinnings of modern science and technology. In addition, the monograph spells out policy implications of an alternative concept of development and…
Sandy Hook : alternative access concept plan and vehicle replacement study
DOT National Transportation Integrated Search
2009-06-01
This study addresses two critical issues of concern to the Sandy Hook Unit of Gateway National : Recreational Area: (1) options for alternative access to Sandy Hook during peak summer season, : particularly when the park is closed to private vehicles...
Alternative Conceptualizations.
ERIC Educational Resources Information Center
Borman, Kathryn M., Ed.; O'Reilly, Patricia, Ed.
1992-01-01
This theme issue of the serial "Educational Foundations" contains five articles devoted to the topic of "Alternative Conceptualizations" of the foundations of education. In "The Concept of Place in the New Sociology of Education," Paul Theobald examines the notion of place in educational theory and practice. Janice…
Rethinking Equity--There Are Alternatives.
ERIC Educational Resources Information Center
Picus, Lawrence O.
1998-01-01
Defines "equity" in terms of three concepts (horizontal equity, vertical equity, and fiscal neutrality), summarizes school finance litigation history, and presents alternative distribution formats to improve student achievement. Enhancing equity and efficiency requires reallocation of existing resources, incentives for improved performance, a more…
ERIC Educational Resources Information Center
Cheong, Irene Poh-Ai; Johari, Marliza; Said, Hardimah; Treagust, David F.
2015-01-01
The need for renewable and non-fossil fuels is now recognised by nations throughout the world. Consequently, an understanding of alternative energy is needed both in schools and in everyday life-long learning situations. This study developed a two-tier instrument to diagnose students' understanding and alternative conceptions about alternative…
NASA Technical Reports Server (NTRS)
Mulqueen, J. A.; Addona, B. M.; Gwaltney, D. A.; Holt, K. A.; Hopkins, R. C.; Matis, J. A.; McRight, P. S.; Popp, C. G.; Sutherlin, S. G.; Thomas, H. D.;
2012-01-01
The primary purpose of this study was to define a point-of-departure prephase A mission concept for the cryogenic propellant storage and transfer technology demonstration mission to be conducted by the NASA Office of the Chief Technologist (OCT). The mission concept includes identification of the cryogenic propellant management technologies to be demonstrated, definition of a representative mission timeline, and definition of a viable flight system design concept. The resulting mission concept will serve as a point of departure for evaluating alternative mission concepts and synthesizing the results of industry- defined mission concepts developed under the OCT contracted studies
ERIC Educational Resources Information Center
Yaman, Fatma; Ayas, Alipasa
2015-01-01
Although concept maps have been used as alternative assessment methods in education, there has been an ongoing debate on how to evaluate students' concept maps. This study discusses how to evaluate students' concept maps as an assessment tool before and after 15 computer-based Predict-Observe-Explain (CB-POE) tasks related to acid-base chemistry.…
ERIC Educational Resources Information Center
Spadaro, Adam; Milliken, Bruce
2013-01-01
Inhibition of Return (IOR) is conventionally defined by slow responses to targets that appear at the same location as a prior attentional cue, relative to a condition in which targets appear at a different location from a prior attentional cue (Posner & Cohen, 1984). A number of recent studies have extended the study of IOR to non-spatial…
Pathogenic microorganisms enter the wastewater collection system from many sources including hospitals, slaughter houses and schools. During treatment at the wastewater treatment plant they become concentrated in the sewage sludge. Prior to any kind of beneficial use the sludge m...
Governors Island alternative transportation study : support to general management plan
DOT National Transportation Integrated Search
2004-12-01
This report, funded by the NPS Alternative Transportation Program (ATP), was commissioned in conjunction with the GMP. As a high-level transportation study, it was intended to inform the GMP planning process and to aid in the conception and developme...
DOT National Transportation Integrated Search
2004-01-09
This manual is a guide to the basic concepts involved and issues to be addressed in acquiring and maintaining vehicles, supporting infrastructure, and personnel needed for alternative transportation systems to serve visitors to national parks, recrea...
High-level radioactive waste management alternatives
DOE Office of Scientific and Technical Information (OSTI.GOV)
None
1974-05-01
A summary of a comprehensive overview study of potential alternatives for long-term management of high-level radioactive waste is presented. The concepts studied included disposal in geologic formations, disposal in seabeds, disposal in ice caps, disposal into space, and elimination by transmutation. (TFD)
NextGen Flight Deck Surface Trajectory-Based Operations (STBO): Contingency Holds
NASA Technical Reports Server (NTRS)
Bakowski, Deborah Lee; Hooey, Becky Lee; Foyle, David C.; Wolter, Cynthia A.; Cheng, Lara W. S.
2013-01-01
The purpose of this pilot-in-the-loop taxi simulation was to investigate a NextGen Surface Trajectory-Based Operations (STBO) concept called "contingency holds." The contingency-hold concept parses a taxi route into segments, allowing an air traffic control (ATC) surface traffic management (STM) system to hold an aircraft when necessary for safety. Under nominal conditions, if the intersection or active runway crossing is clear, the hold is removed, allowing the aircraft to continue taxiing without slowing, thus improving taxi efficiency, while minimizing the excessive brake use, fuel burn, and emissions associated with stop-and-go taxi. However, when a potential traffic conflict exists, the hold remains in place as a fail-safe mechanism. In this departure operations simulation, the taxi clearance included a required time of arrival (RTA) to a specified intersection. The flight deck was equipped with speed-guidance avionics to aid the pilot in safely meeting the RTA. On two trials, the contingency hold was not released, and pilots were required to stop. On two trials the contingency hold was released 15 sec prior to the RTA, and on two trials the contingency hold was released 30 sec prior to the RTA. When the hold remained in place, all pilots complied with the hold. Results also showed that when the hold was released at 15-sec or 30-sec prior to the RTA, the 30-sec release allowed pilots to maintain nominal taxi speed, thus supporting continuous traffic flow; whereas, the 15-sec release did not. The contingency-hold concept, with at least a 30-sec release, allows pilots to improve taxiing efficiency by reducing braking, slowing, and stopping, but still maintains safety in that no pilots "busted" the clearance holds. Overall, the evidence suggests that the contingency-hold concept is a viable concept for optimizing efficiency while maintaining safety.
ERIC Educational Resources Information Center
Vosniadou, Stella; Skopeliti, Irini
2017-01-01
The present research tested the hypothesis that the reading of science text can create new misconceptions in students with incongruent prior knowledge, and that these new misconceptions will be similar to the fragmented and synthetic conceptions obtained in prior developmental research. Ninety-nine third- and fifth-grade children read and recalled…
The Effect of Case-Based Instruction on 10th Grade Students' Understanding of Gas Concepts
ERIC Educational Resources Information Center
Yalçinkaya, Eylem; Boz, Yezdan
2015-01-01
The main purpose of the present study was to investigate the effect of case-based instruction on remedying 10th grade students' alternative conceptions related to gas concepts. 128 tenth grade students from two high schools participated in this study. In each school, one of the classes was randomly assigned as the experimental group and the other…
ERIC Educational Resources Information Center
Yalcinkaya, Eylem; Tastan-Kirik, Ozgecan; Boz, Yezdan; Yildiran, Demet
2012-01-01
Background: Case-based learning (CBL) is simply teaching the concept to the students based on the cases. CBL involves a case, which is a scenario based on daily life, and study questions related to the case, which allows students to discuss their ideas. Chemical kinetics is one of the most difficult concepts for students in chemistry. Students…
ERIC Educational Resources Information Center
Pesonen, Henri; Kontu, Elina; Saarinen, Minna; Pirttimaa, Raija
2016-01-01
The aim of this study was to examine conceptions associated with sense of belonging (SEBE) in Finnish general and special school placements for pupils with special education needs. Five pupils were selected for this study by means of purposive sampling. They had a history of several school placements prior to arriving at their current special…
ERIC Educational Resources Information Center
Carvalho, Graca; Silva, Rui; Lima, Nelson; Coquet, Eduarda; Clement, Pierre
2004-01-01
A cross-sectional study of Portuguese primary school pupils' conceptions on digestion and the digestive tract was carried out before and after teaching this topic. Pupils of the prior four school years (5/6 to 9/10 year old) drew what happens to a cookie inside their body. In some cases they also wrote a short text or were interviewed. To identify…
ERIC Educational Resources Information Center
Neubrand, Charlotte; Borzikowsky, Christoph; Harms, Ute
2016-01-01
Evolutionary theory constitutes the overarching concept in biology. There is hardly any other concept that is more complex, and causes more difficulties in learning and teaching. One instructional approach in optimizing the learning of complex topics is to use worked examples combined with self-explanation prompts that fit to the prior knowledge…
Less-Complex Method of Classifying MPSK
NASA Technical Reports Server (NTRS)
Hamkins, Jon
2006-01-01
An alternative to an optimal method of automated classification of signals modulated with M-ary phase-shift-keying (M-ary PSK or MPSK) has been derived. The alternative method is approximate, but it offers nearly optimal performance and entails much less complexity, which translates to much less computation time. Modulation classification is becoming increasingly important in radio-communication systems that utilize multiple data modulation schemes and include software-defined or software-controlled receivers. Such a receiver may "know" little a priori about an incoming signal but may be required to correctly classify its data rate, modulation type, and forward error-correction code before properly configuring itself to acquire and track the symbol timing, carrier frequency, and phase, and ultimately produce decoded bits. Modulation classification has long been an important component of military interception of initially unknown radio signals transmitted by adversaries. Modulation classification may also be useful for enabling cellular telephones to automatically recognize different signal types and configure themselves accordingly. The concept of modulation classification as outlined in the preceding paragraph is quite general. However, at the present early stage of development, and for the purpose of describing the present alternative method, the term "modulation classification" or simply "classification" signifies, more specifically, a distinction between M-ary and M'-ary PSK, where M and M' represent two different integer multiples of 2. Both the prior optimal method and the present alternative method require the acquisition of magnitude and phase values of a number (N) of consecutive baseband samples of the incoming signal + noise. The prior optimal method is based on a maximum- likelihood (ML) classification rule that requires a calculation of likelihood functions for the M and M' hypotheses: Each likelihood function is an integral, over a full cycle of carrier phase, of a complicated sum of functions of the baseband sample values, the carrier phase, the carrier-signal and noise magnitudes, and M or M'. Then the likelihood ratio, defined as the ratio between the likelihood functions, is computed, leading to the choice of whichever hypothesis - M or M'- is more likely. In the alternative method, the integral in each likelihood function is approximated by a sum over values of the integrand sampled at a number, 1, of equally spaced values of carrier phase. Used in this way, 1 is a parameter that can be adjusted to trade computational complexity against the probability of misclassification. In the limit as 1 approaches infinity, one obtains the integral form of the likelihood function and thus recovers the ML classification. The present approximate method has been tested in comparison with the ML method by means of computational simulations. The results of the simulations have shown that the performance (as quantified by probability of misclassification) of the approximate method is nearly indistinguishable from that of the ML method (see figure).
Nothing to it: Precursors to a Zero Concept in Preschoolers
Merritt, Dustin J.; Brannon, Elizabeth M.
2013-01-01
Do young children understand the numerical value of empty sets prior to developing a concept of symbolic zero? Are empty sets represented as mental magnitudes? In order to investigate these questions, we tested 4-year old children and adults with a numerical ordering task in which the goal was to select two stimuli in ascending numerical order with occasional empty set stimuli. Both children and adults showed distance effects for empty sets.. Children who were unable to order the symbol zero (e.g., 0 < 1), but who successfully ordered countable integers (e.g., 2 < 4) nevertheless showed distance effects with empty sets. These results suggest that empty sets are represented on the same numerical continuum as non-empty sets and that children represent empty sets numerically prior to understanding symbolic zero. PMID:23219980
A study of spacecraft technology and design concepts. Volume 2: Appendices
NASA Technical Reports Server (NTRS)
Zylius, F. A.
1985-01-01
Electrical, mechanical, and software subsystem needs in the Post 1990 space operations environment are considered as well as the effect of radiation environment on spacecraft configuration. Criteria are given for selecting a specific design or technology concept from among the alternatives available.
The affordance-matching hypothesis: how objects guide action understanding and prediction
Bach, Patric; Nicholson, Toby; Hudson, Matthew
2014-01-01
Action understanding lies at the heart of social interaction. Prior research has often conceptualized this capacity in terms of a motoric matching of observed actions to an action in one’s motor repertoire, but has ignored the role of object information. In this manuscript, we set out an alternative conception of intention understanding, which places the role of objects as central to our observation and comprehension of the actions of others. We outline the current understanding of the interconnectedness of action and object knowledge, demonstrating how both rely heavily on the other. We then propose a novel framework, the affordance-matching hypothesis, which incorporates these findings into a simple model of action understanding, in which object knowledge—what an object is for and how it is used—can inform and constrain both action interpretation and prediction. We will review recent empirical evidence that supports such an object-based view of action understanding and we relate the affordance matching hypothesis to recent proposals that have re-conceptualized the role of mirror neurons in action understanding. PMID:24860468
NASA Technical Reports Server (NTRS)
Zachary, A. T.
1973-01-01
Analysis and design of an optimum LO2/LH2, combustion topping cycle, 88,964 Newtons (20,000-pound) thrust, liquid rocket engine was conducted. The design selected is well suited to high-energy, upper-stage engine applications such as the Space Tug and embodies features directed toward optimization of vehicle performance. A configuration selection was conducted based on prior Air Force Contracts, and additional criteria for optimum stage performance. Following configuration selection, analyses and design of the major components and engine systems were conducted to sufficient depth to provide layout drawings suitable for subsequent detailing. In addition, engine packaging to a common interface and a retractable nozzle concept were defined. Alternative development plans and related costs were also established. The design embodies high-performance, low-weight, low NPSH requirements (saturated propellant inlet conditions at start), idle-mode operation, and autogenous pressurization. The design is the result of the significant past and current LO2/LH2 technology efforts of the NASA centers and the Air Force, as well as company-funded programs.
Potentiometric perchlorate determination at nanomolar concentrations in vegetables.
Leoterio, Dilmo M S; Paim, Ana Paula S; Belian, Mônica F; Galembeck, André; Lavorante, André F; Pinto, Edgar; Amorim, Célia G; Araújo, Alberto N; Montenegro, Maria C B S M
2017-07-15
In this work, an expeditious method based on the multi-commutated flow-analysis concept with potentiometric detection is proposed to perform determinations of the emergent contaminant perchlorate in vegetable matrices down to nanomolar concentration. To accomplish the task, a tubular shaped potentiometric sensor selective to perchlorate ion was constructed with a PVC membrane containing 12mmol/kg of the polyamine bisnaphthalimidopropyl-4,4'-diaminodiphenylmethane and 2-nitrophenyl phenyl ether 68% (w/w) as plasticizer casted on a conductive epoxy resin. Under optimal flow conditions, the sensor responded linearly in the concentration range of 6.3×10 -7 -1.0×10 -3 mol/L perchlorate. In order to extend the determinations to lower concentrations (4.6(±1.3)×10 -10 mol/L perchlorate), a column packed with 70mg of sodium 2,5,8,11,14-pentaoxa-1-silacyclotetradecane-polymer was coupled to the flow-system thus enabling prior pre-concentration of the perchlorate. The proposed procedure provides a simpler alternative for the determination of perchlorate in foods, nowadays only allowed by sophisticated and expensive equipment and laborious methods. Copyright © 2017 Elsevier Ltd. All rights reserved.
Supersensitive ancilla-based adaptive quantum phase estimation
NASA Astrophysics Data System (ADS)
Larson, Walker; Saleh, Bahaa E. A.
2017-10-01
The supersensitivity attained in quantum phase estimation is known to be compromised in the presence of decoherence. This is particularly patent at blind spots—phase values at which sensitivity is totally lost. One remedy is to use a precisely known reference phase to shift the operation point to a less vulnerable phase value. Since this is not always feasible, we present here an alternative approach based on combining the probe with an ancillary degree of freedom containing adjustable parameters to create an entangled quantum state of higher dimension. We validate this concept by simulating a configuration of a Mach-Zehnder interferometer with a two-photon probe and a polarization ancilla of adjustable parameters, entangled at a polarizing beam splitter. At the interferometer output, the photons are measured after an adjustable unitary transformation in the polarization subspace. Through calculation of the Fisher information and simulation of an estimation procedure, we show that optimizing the adjustable polarization parameters using an adaptive measurement process provides globally supersensitive unbiased phase estimates for a range of decoherence levels, without prior information or a reference phase.
Development of the ASTRI heliostat
NASA Astrophysics Data System (ADS)
Coventry, Joe; Arjomandi, Maziar; Barry, John; Blanco, Manuel; Burgess, Greg; Campbell, Jonathan; Connor, Phil; Emes, Matthew; Fairman, Philip; Farrant, David; Ghanadi, Farzin; Grigoriev, Victor; Hall, Colin; Koltun, Paul; Lewis, David; Martin, Scott; Nathan, Graham; Pye, John; Qiu, Ang; Stuart, Wayne; Tang, Youhong; Venn, Felix; Yu, Jeremy
2016-05-01
The Australian Solar Thermal Research Initiative (ASTRI) aims to develop a high optical quality heliostat with target cost - manufactured, installed and operational - of 90 AUD/m2. Three different heliostat design concepts are described, each with features identified during a prior scoping study as having the potential to contribute to cost reduction compared to the current state-of-the-art. The three concepts which are being developed will be down-selected to a single concept for testing in late 2016. The heliostat concept development work is supported by technology development streams, developing novel sandwich panel mirror facet structures, analysing and testing wind loads on heliostats in both stow and operation positions, and developing new heliostat field layouts and software tools for optical analysis of heliostats design concepts.
Sustainability - What are the Odds? Guessing the Future of our Environment, Economy, and Society
This article examines the concept of sustainability from a global perspective, describing how alternative futures might develop in the environmental, economic, and social dimensions. The alternatives to sustainability appear to be (a) a catastrophic failure of life support, econo...
Learning Science through Creating a `Slowmation': A case study of preservice primary teachers
NASA Astrophysics Data System (ADS)
Hoban, Garry; Nielsen, Wendy
2013-01-01
Many preservice primary teachers have inadequate science knowledge, which often limits their confidence in implementing the subject. This paper proposes a new way for preservice teachers to learn science by designing and making a narrated stop-motion animation as an instructional resource to explain a science concept. In this paper, a simplified way for preservice teachers to design and make an animation called 'slowmation' (abbreviated from 'slow animation') is exemplified. A case study of three preservice primary teachers creating one from start to finish over 2 h was conducted to address the following research question: How do the preservice primary teachers create a slowmation and how does this process influence their science learning? The method of inquiry used a case study design involving pre- and post-individual interviews in conjunction with a discourse analysis of video and audio data recorded as they created a slowmation. The data illustrate how the preservice teachers' science learning was related to their prior knowledge and how they iteratively revisited the content through the construction of five representations as a cumulative semiotic progression: (i) research notes; (ii) storyboard; (iii) models; (iv) digital photographs; culminating in (v) the narrated animation. This progression enabled the preservice teachers to revisit the content in each representation and make decisions about which modes to use and promoted social interaction. Creating a slowmation facilitated the preservice teachers' learning about the life cycle of a ladybird beetle and revised their alternative conceptions.
NASA Astrophysics Data System (ADS)
Seiller, G.; Anctil, F.; Roy, R.
2017-09-01
This paper outlines the design and experimentation of an Empirical Multistructure Framework (EMF) for lumped conceptual hydrological modeling. This concept is inspired from modular frameworks, empirical model development, and multimodel applications, and encompasses the overproduce and select paradigm. The EMF concept aims to reduce subjectivity in conceptual hydrological modeling practice and includes model selection in the optimisation steps, reducing initial assumptions on the prior perception of the dominant rainfall-runoff transformation processes. EMF generates thousands of new modeling options from, for now, twelve parent models that share their functional components and parameters. Optimisation resorts to ensemble calibration, ranking and selection of individual child time series based on optimal bias and reliability trade-offs, as well as accuracy and sharpness improvement of the ensemble. Results on 37 snow-dominated Canadian catchments and 20 climatically-diversified American catchments reveal the excellent potential of the EMF in generating new individual model alternatives, with high respective performance values, that may be pooled efficiently into ensembles of seven to sixty constitutive members, with low bias and high accuracy, sharpness, and reliability. A group of 1446 new models is highlighted to offer good potential on other catchments or applications, based on their individual and collective interests. An analysis of the preferred functional components reveals the importance of the production and total flow elements. Overall, results from this research confirm the added value of ensemble and flexible approaches for hydrological applications, especially in uncertain contexts, and open up new modeling possibilities.
NASA Astrophysics Data System (ADS)
Haili, Hasnawati; Maknun, Johar; Siahaan, Parsaoran
2017-08-01
Physics is a lessons that related to students' daily experience. Therefore, before the students studying in class formally, actually they have already have a visualization and prior knowledge about natural phenomenon and could wide it themselves. The learning process in class should be aimed to detect, process, construct, and use students' mental model. So, students' mental model agree with and builds in the right concept. The previous study held in MAN 1 Muna informs that in learning process the teacher did not pay attention students' mental model. As a consequence, the learning process has not tried to build students' mental modelling ability (MMA). The purpose of this study is to describe the improvement of students' MMA as a effect of problem solving based learning model with multiple representations approach. This study is pre experimental design with one group pre post. It is conducted in XI IPA MAN 1 Muna 2016/2017. Data collection uses problem solving test concept the kinetic theory of gasses and interview to get students' MMA. The result of this study is clarification students' MMA which is categorized in 3 category; High Mental Modelling Ability (H-MMA) for 7
Level of Skill Argued Students on Physics Material
NASA Astrophysics Data System (ADS)
Viyanti, V.; Cari, C.; Sunarno, W.; Prasetyo, Z. K.
2017-09-01
This study aims to analyze the prior knowledge of students to map the level of skills to argue floating and sinking material. Prior knowledge is the process of concept formation in cognitive processes spontaneously or based on student experience. The study population is high school students of class XI. The sample selection using cluster random sampling, obtained the number of sampel as many as 50 student. The research used descriptive survey method. The data were obtained through a multiple choice test both grounded and interviewed. The data analyzed refers to: alignment the concept and the activity of developing the skill of the argument. The result obtained by the average level of skill argue in terms of the prior knowladge of on “Level 2”. The data show that students have difficulty expressing simple arguments consisting of only one statement. This indicates a lack of student experience in cultivating argumentative skills in their learning. The skill level mapping argued in this study to be a reference for researchers to provide feedback measures to obtain positive change in cognitive conflict argued.
Confidence of compliance: a Bayesian approach for percentile standards.
McBride, G B; Ellis, J C
2001-04-01
Rules for assessing compliance with percentile standards commonly limit the number of exceedances permitted in a batch of samples taken over a defined assessment period. Such rules are commonly developed using classical statistical methods. Results from alternative Bayesian methods are presented (using beta-distributed prior information and a binomial likelihood), resulting in "confidence of compliance" graphs. These allow simple reading of the consumer's risk and the supplier's risks for any proposed rule. The influence of the prior assumptions required by the Bayesian technique on the confidence results is demonstrated, using two reference priors (uniform and Jeffreys') and also using optimistic and pessimistic user-defined priors. All four give less pessimistic results than does the classical technique, because interpreting classical results as "confidence of compliance" actually invokes a Bayesian approach with an extreme prior distribution. Jeffreys' prior is shown to be the most generally appropriate choice of prior distribution. Cost savings can be expected using rules based on this approach.
Rufibach, Kaspar; Burger, Hans Ulrich; Abt, Markus
2016-09-01
Bayesian predictive power, the expectation of the power function with respect to a prior distribution for the true underlying effect size, is routinely used in drug development to quantify the probability of success of a clinical trial. Choosing the prior is crucial for the properties and interpretability of Bayesian predictive power. We review recommendations on the choice of prior for Bayesian predictive power and explore its features as a function of the prior. The density of power values induced by a given prior is derived analytically and its shape characterized. We find that for a typical clinical trial scenario, this density has a u-shape very similar, but not equal, to a β-distribution. Alternative priors are discussed, and practical recommendations to assess the sensitivity of Bayesian predictive power to its input parameters are provided. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.
Granath, Johanna; Asztély, Anna; Lundgren, Ted
2018-04-30
To assess the occurrence of interproximal grinding as a caries therapy in primary molars, to what degree grinding replaced conventional restorative caries therapy, to what extent anaesthesia was used while grinding and to assess open comments about attitudes about grinding. A questionnaire was sent to 108 public dental service clinics with questions concerning the use of grinding as a therapy and alternative to restorative treatment, the use of anaesthesia prior to conventional caries therapy and grinding, respectively. In addition, a content analysis of open comments about grinding was performed. Grinding had been performed in 96% of the clinics. Two-thirds of the dentists used grinding as an alternative to conventional restorative treatment at some point. Most dentists used anaesthesia prior to restorative therapy. Prior to grinding, the frequency of anaesthesia was lower (median 5.0) than for conventional restorative therapy (median 8.7) (p < .001). The open comment analysis revealed complex reasons for the use of grinding. Grinding has been widely practiced in parts of Sweden, is presently a technique employed by a multitude of dentists, and that anaesthesia is used less frequently prior to grinding, in comparison to conventional restorative therapy. Dentist considered grinding as a treatment option in specific situations.
Mess, Jean-Nicholas; Taillon, Marie-Pierre; Côté, Cynthia; Garofolo, Fabio
2012-12-01
Thiorphan, the active metabolite of racecadotril, can undergo oxidation in biological matrices such as blood and plasma. In bioanalysis, a general approach for the stabilization of such a molecule is to derivatize the thiol group to a more stable thioether, often requiring complex handling procedures at the clinical site. In this research, the concept of dried blood spot (DBS) on-card derivatization was evaluated to stabilize thiorphan. DBS cards were in-house pre-treated with 2-bromo-3'-methoxyacetophenone and left to dry prior to blood spotting. Thiorphan was shown to be effectively derivatized to thiorphan-methoxyacetophenone once applied on the in-house pre-treated cards. Thiorphan-methoxyacetophenone was extracted by soaking a 6 mm DBS punch in methanol containing the internal standard (thiorphan-methoxyacetophenone-D₅). Chromatographic separation was achieved on a Waters XBridge C₁₈ column with a gradient elution of 5 mM NH₄HCO₃ and methanol in 2.5 min and detection by ESI(+)/MS/MS. A linear (weighted 1/x²) relationship was obtained over a concentration range of 5.00-600.00 ng/mL. The assay met regulatory guidelines acceptance criteria for sensitivity, selectivity, precision and accuracy, matrix effect, recovery, dilution integrity and multiple stability evaluations. The DBS on-card derivatization has shown to be an easy and reliable alternative form of sample collection for the quantification of thiorphan. Copyright © 2012 John Wiley & Sons, Ltd.
Blind image deconvolution using the Fields of Experts prior
NASA Astrophysics Data System (ADS)
Dong, Wende; Feng, Huajun; Xu, Zhihai; Li, Qi
2012-11-01
In this paper, we present a method for single image blind deconvolution. To improve its ill-posedness, we formulate the problem under Bayesian probabilistic framework and use a prior named Fields of Experts (FoE) which is learnt from natural images to regularize the latent image. Furthermore, due to the sparse distribution of the point spread function (PSF), we adopt a Student-t prior to regularize it. An improved alternating minimization (AM) approach is proposed to solve the resulted optimization problem. Experiments on both synthetic and real world blurred images show that the proposed method can achieve results of high quality.
NASA Astrophysics Data System (ADS)
Rousis, Damon A.
The expected growth of civil aviation over the next twenty years places significant emphasis on revolutionary technology development aimed at mitigating the environmental impact of commercial aircraft. As the number of technology alternatives grows along with model complexity, current methods for Pareto finding and multiobjective optimization quickly become computationally infeasible. Coupled with the large uncertainty in the early stages of design, optimal designs are sought while avoiding the computational burden of excessive function calls when a single design change or technology assumption could alter the results. This motivates the need for a robust and efficient evaluation methodology for quantitative assessment of competing concepts. This research presents a novel approach that combines Bayesian adaptive sampling with surrogate-based optimization to efficiently place designs near Pareto frontier intersections of competing concepts. Efficiency is increased over sequential multiobjective optimization by focusing computational resources specifically on the location in the design space where optimality shifts between concepts. At the intersection of Pareto frontiers, the selection decisions are most sensitive to preferences place on the objectives, and small perturbations can lead to vastly different final designs. These concepts are incorporated into an evaluation methodology that ultimately reduces the number of failed cases, infeasible designs, and Pareto dominated solutions across all concepts. A set of algebraic samples along with a truss design problem are presented as canonical examples for the proposed approach. The methodology is applied to the design of ultra-high bypass ratio turbofans to guide NASA's technology development efforts for future aircraft. Geared-drive and variable geometry bypass nozzle concepts are explored as enablers for increased bypass ratio and potential alternatives over traditional configurations. The method is shown to improve sampling efficiency and provide clusters of feasible designs that motivate a shift towards revolutionary technologies that reduce fuel burn, emissions, and noise on future aircraft.
Grose, Rose Grace; Grabe, Shelly
2014-01-01
We extend objectification theory research to consider the relationship between self-objectification and attitudes toward an alternative menstrual product in a diverse sample of female undergraduates from the United States (N = 151). We use a survey design to investigate attitudes toward one's menstruation as a potential mechanism that may explain this relationship. Reactions to an alternative menstrual product were predominantly negative, supporting prior research on stigma and shame surrounding menstruation. Exploratory structural equation modeling revealed attitudes toward one's menstruation mediated the relationship between self-objectification and participants' reactions to an alternative menstrual product. Implications for women's health are discussed.
Variables Affecting Physics Achievement
ERIC Educational Resources Information Center
Lawrenz, Frances; Wood, Nathan B.; Kirchhoff, Allison; Kim, Nam Keol; Eisenkraft, Arthur
2009-01-01
Much research has focused on student views about physics concepts, with an emphasis on the identification of alternative conceptions, and how curricula and professional development may ameliorate the situation. However, there has been little work on determining the extent of, and in separating, the student and teacher/classroom level variables…
In-Vehicle Signing Concepts: An Analytical Precursor to an In-Vehicle Information System
DOT National Transportation Integrated Search
1996-01-01
The purpose of the project described in this report is to develop alternative In-Vehicle Signing (IVS) system concepts based on allocation of the functions associated with driving a road vehicle. In the driving milieu, tasks can be assigned to one of...
The Single Crew Module Concept for Exploration
NASA Technical Reports Server (NTRS)
Chambliss, Joe
2012-01-01
Many concepts have been proposed for exploring space. In early 2010 presidential direction called for reconsidering the approach to address changes in exploration destinations, use of new technologies and development of new capabilities to support exploration of space. Considering the proposed new technology and capabilities that NASA was directed to pursue, the single crew module (SCM) concept for a more streamlined approach to the infrastructure and conduct of exploration missions was developed. The SCM concept combines many of the new promising technologies with a central concept of mission architectures that uses a single habitat module for all phases of an exploration mission. Integrating mission elements near Earth and fully fueling them prior to departure of the vicinity of Earth provides the capability of using the single habitat both in transit to an exploration destination and while exploring the destination. The concept employs the capability to return the habitat and interplanetary propulsion system to Earth vicinity so that those elements can be reused on subsequent exploration missions. This paper describes the SCM concept, provides a top level mass estimate for the elements needed and trades the concept against Many concepts have been proposed for exploring space. In early 2010 presidential direction called for reconsidering the approach to address changes in exploration destinations, use of new technologies and development of new capabilities to support exploration of space. Considering the proposed new technology and capabilities that NASA was directed to pursue, the single crew module (SCM) concept for a more streamlined approach to the infrastructure and conduct of exploration missions was developed. The SCM concept combines many of the new promising technologies with a central concept of mission architectures that uses a single habitat module for all phases of an exploration mission. Integrating mission elements near Earth and fully fueling them prior to departure of the vicinity of Earth provides the capability of using the single habitat both in transit to an exploration destination and while exploring the destination. The concept employs the capability to return the habitat and interplanetary propulsion system to Earth vicinity so that those elements can be reused on subsequent exploration missions. This paper describes the SCM concept, provides a top level mass estimate for the elements needed and trades the concept against Constellation approaches for Lunar, Near Earth Asteroid and Mars Surface missions.
ECLS systems for a lunar base - A baseline and some alternate concepts
NASA Technical Reports Server (NTRS)
Hypes, Warren D.; Hall, John B., Jr.
1988-01-01
A baseline ECLS system for a lunar base manned intermittently by four crewmembers and later permanently occupied by eight crewmembers has been designed. A summary of the physical characteristics for the intermittently manned and the continuously manned bases is given. Since Space Station inheritance is a key assumption in the mission models, the ECLS system components are distributed within Space Station modules and nodes. A 'core assembly' concept is then developed to meet the objectives of both phases of the ECLS system. A supplementary study is discussed which assessed tankage requirements, penalties incurred by adding subsystem redundancy and by pressurizing large surface structures, and difficulties imposed by intermittent occupancy. Alternate concepts using lunar-derived oxygen, the gravitational field as a design aid, and a city utility-type ECLS system are also discussed.
AAFES Shopping Center Environmental Assessment
2009-08-01
Plan H2S Hydrogen Sulfide SO2 Sulfur Dioxide HWMP Hazardous Waste Management Plan SMW Strategic Missile Wing ICBM Intercontinental Ballistic Missile...the no-action alternative. Land Management and Use. A waiver would be needed prior to construction to change the land use designation from Open...occur under the no-action alternative. Hazardous Materials and Waste Management . No changes to hazardous materials or waste streams would occur
Preliminary Feasibility Report Stage II, Lorain Small-Boat Harbor, Lorain, Ohio. Revision.
1982-03-01
effects of each alternative plan. Activities consist of analyzing each measure to deter- mine potential sources , the incidence, and the magni- tude...using existing reports, available data sources , visual inspections, onsite interviews, and workshop discussions. Alternative small-boat harbor designs...were developed to a consistent level of detail. Prior reports were used as data sources for preliminary design of break- waters, including length
ERIC Educational Resources Information Center
Milunic, Marjorie
2013-01-01
This study investigated the perceptions of three alternative and three traditional route participants of their experiences prior to receiving teacher certification. It further investigated whether their experiences proved to be educative, mis-educative, or a combination of the two. Observations, interviews, and lesson plans were analyzed according…
Learning style and concept acquisition of community college students in introductory biology
NASA Astrophysics Data System (ADS)
Bobick, Sandra Burin
This study investigated the influence of learning style on concept acquisition within a sample of community college students in a general biology course. There are two subproblems within the larger problem: (1) the influence of demographic variables (age, gender, number of college credits, prior exposure to scientific information) on learning style, and (2) the correlations between prior scientific knowledge, learning style and student understanding of the concept of the gene. The sample included all students enrolled in an introductory general biology course during two consecutive semesters at an urban community college. Initial data was gathered during the first week of the semester, at which time students filled in a short questionnaire (age, gender, number of college credits, prior exposure to science information either through reading/visual sources or a prior biology course). Subjects were then given the Inventory of Learning Processes-Revised (ILP-R) which measures general preferences in five learning styles; Deep Learning; Elaborative Learning, Agentic Learning, Methodical Learning and Literal Memorization. Subjects were then given the Gene Conceptual Knowledge pretest: a 15 question objective section and an essay section. Subjects were exposed to specific concepts during lecture and laboratory exercises. At the last lab, students were given the Genetics Conceptual Knowledge Posttest. Pretest/posttest gains were correlated with demographic variables and learning styles were analyzed for significant correlations. Learning styles, as the independent variable in a simultaneous multiple regression, were significant predictors of results on the gene assessment tests, including pretest, posttest and gain. Of the learning styles, Deep Learning accounted for the greatest positive predictive value of pretest essay and pretest objective results. Literal Memorization was a significant negative predictor for posttest essay, essay gain and objective gain. Simultaneous multiple regression indicated that demographic variables were significant positive predictors for Methodical, Deep and Elaborative Learning Styles. Stepwise multiple regression resulted in number of credits, Read Science and gender (female) as significant predictors of learning styles. The findings of this study emphasize the importance of learning styles in conceptual understanding of the gene and the correlation of nonformal exposure to science information with learning style and conceptual understanding.
NASA Technical Reports Server (NTRS)
Nickol, Craig L.; Guynn, Mark D.; Kohout, Lisa L.; Ozoroski, Thomas A.
2007-01-01
The objective of this study was to develop a variety of High Altitude Long Endurance (HALE) Unmanned Aerial Vehicle (UAV) conceptual designs for two operationally useful missions (hurricane science and communications relay) and compare their performance and cost characteristics. Sixteen potential HALE UAV configurations were initially developed, including heavier-than-air (HTA) and lighter-than-air (LTA) concepts with both consumable fuel and solar regenerative (SR) propulsion systems. Through an Analysis of Alternatives (AoA) down select process, the two leading consumable fuel configurations (one each from the HTA and LTA alternatives) and an HTA SR configuration were selected for further analysis. Cost effectiveness analysis of the consumable fuel configurations revealed that simply maximizing vehicle endurance can lead to a sub-optimum system solution. An LTA concept with a hybrid propulsion system (solar arrays and a hydrogen-air proton exchange membrane fuel cell) was found to have the best mission performance; however, an HTA diesel-fueled wing-body-tail configuration emerged as the preferred consumable fuel concept because of the large size and technical risk of the LTA concept. The baseline missions could not be performed by even the best HTA SR concept. Mission and SR technology trade studies were conducted to enhance understanding of the potential capabilities of such a vehicle. With near-term technology SR-powered HTA vehicles are limited to operation in favorable solar conditions, such as the long days and short nights of summer at higher latitudes. Energy storage system specific energy and solar cell efficiency were found to be the key technology areas for enhancing HTA SR performance.
An Alternative to Ability Grouping
ERIC Educational Resources Information Center
Tomlinson, Carol Ann
2006-01-01
Ability grouping is a common approach to dealing with student variance in learning. In general, findings suggest that such an approach to dealing with student differences is disadvantageous to students who struggle in school and advantageous to advanced learners. The concept of differentiation suggests that there is another alternative to…
Beyond the Boundaries: Critical Thinking and Differing Cultural Perspectives
ERIC Educational Resources Information Center
Bailin, Sharon; Battersby, Mark
2009-01-01
After outlining arguments for the general epistemological presumption in favour of taking into consideration alternative perspectives from other cultures, the article details several examples in which such an examination yields epistemic benefits and challenges. First, our example of alternative conceptions of art demonstrates that a western…
Preliminary Structural Sizing and Alternative Material Trade Study of CEV Crew Module
NASA Technical Reports Server (NTRS)
Bednarcyk, Brett A.; Arnold, Steve M.; Collier, Craig S.; Yarrington, Phillip W.
2007-01-01
This paper presents the results of a preliminary structural sizing and alternate material trade study for NASA s Crew Exploration Vehicle (CEV) Crew Module (CM). This critical CEV component will house the astronauts during ascent, docking with the International Space Station, reentry, and landing. The alternate material design study considers three materials beyond the standard metallic (aluminum alloy) design that resulted from an earlier NASA Smart Buyer Team analysis. These materials are graphite/epoxy composite laminates, discontinuously reinforced SiC/Al (DRA) composites, and a novel integrated panel material/concept known as WebCore. Using the HyperSizer (Collier Research and Development Corporation) structural sizing software and NASTRAN finite element analysis code, a comparison is made among these materials for the three composite CM concepts considered by the 2006 NASA Engineering and Safety Center Composite Crew Module project.
The Otto-engine-equivalent vehicle concept
NASA Technical Reports Server (NTRS)
Dowdy, M. W.; Couch, M. D.
1978-01-01
A vehicle comparison methodology based on the Otto-Engine Equivalent (OEE) vehicle concept is described. As an illustration of this methodology, the concept is used to make projections of the fuel economy potential of passenger cars using various alternative power systems. Sensitivities of OEE vehicle results to assumptions made in the calculational procedure are discussed. Factors considered include engine torque boundary, rear axle ratio, performance criteria, engine transient response, and transmission shift logic.
New Concept Study for Repair of Bomb-Damaged Runways. Volume I. Concept Identification.
1979-09-01
Expanded polystyrene beads would be pneumatically mixed with the cement to form a low density material. Initially, the ratio of foam to cement would...the combinations are presented with this concept. PRIMARY MATERIALS 0 Expanded polystyrene foam beads * Graded aggregate * Quick setting cement 61 E-4...probability of success - high ALTERNATE MATERIALS * Expanded polystyrene foam beads * Organic binders Furan Methyl Methacrylate Epoxy Aminos * Graded
NASA Astrophysics Data System (ADS)
Gamor, Keysha Ingram
This paper contains a research study that investigated the relative efficacy of using both a traditional paper-and-pencil assessment instrument and an alternative, virtual reality (VR) assessment instrument to assist educators and/or instructional designers in measuring learning in a virtual reality learning environment. To this end, this research study investigated assessment in VR, with the goal of analyzing aspects of student learning in VR that are feasible to access or capture by traditional assessments and alternative assessments. The researcher also examined what additional types of learning alternative assessments may offer. More specifically, this study compared the effectiveness of a traditional method with an alternative (performance-based) method of assessment that was used to examine the ability of the tools to accurately evidence the levels of students' understanding and learning. The domain area was electrostatics, a complex, abstract multidimensional concept, with which students often experience difficulty. Outcomes of the study suggest that, in the evaluation of learning in an immersive VR learning environment, assessments would most accurately manifest student learning if the assessment measure matched the learning environment itself. In this study, learning and assessing in the VR environment yielded higher final test scores than learning in VR and testing with traditional paper-and-pencil. Being able to transfer knowledge from a VR environment to other situations is critical in demonstrating the overall level of understanding of a concept. For this reason, the researcher recommends a combination of testing measures to enhance understanding of complex, abstract concepts.
NASA Astrophysics Data System (ADS)
Ding, Lin
2014-02-01
Discipline-based science concept assessments are powerful tools to measure learners' disciplinary core ideas. Among many such assessments, the Brief Electricity and Magnetism Assessment (BEMA) has been broadly used to gauge student conceptions of key electricity and magnetism (E&M) topics in college-level introductory physics courses. Differing from typical concept inventories that focus only on one topic of a subject area, BEMA covers a broad range of topics in the electromagnetism domain. In spite of this fact, prior studies exclusively used a single aggregate score to represent individual students' overall understanding of E&M without explicating the construct of this assessment. Additionally, BEMA has been used to compare traditional physics courses with a reformed course entitled Matter and Interactions (M&I). While prior findings were in favor of M&I, no empirical evidence was sought to rule out possible differential functioning of BEMA that may have inadvertently advantaged M&I students. In this study, we used Rasch analysis to seek two missing pieces regarding the construct and differential functioning of BEMA. Results suggest that although BEMA items generally can function together to measure the same construct of application and analysis of E&M concepts, several items may need further revision. Additionally, items that demonstrate differential functioning for the two courses are detected. Issues such as item contextual features and student familiarity with question settings may underlie these findings. This study highlights often overlooked threats in science concept assessments and provides an exemplar for using evidence-based reasoning to make valid inferences and arguments.
A concept for improved fire-safety through coated fillers
NASA Technical Reports Server (NTRS)
Ramohalli, K.
1977-01-01
A possible method is examined for obtaining a high value of thermal conductivity before ignition and a low value after ignition in standard composite materials. The idea is to coat fiberglass, alumina trihydrate, and similar fillers with specially selected chemicals prior to using polymer resins. The amount of the coat constitutes typically less than 5% of the material's total weight. The experimental results obtained are consistent with the basic concept.
Reverse Vesicouterine Fold Dissection for Laparoscopic Hysterectomy After Prior Cesarean Deliveries.
Nezhat, Camran; Grace, Lindsey A; Razavi, Gity M; Mihailide, Catalina; Bamford, Holden
2016-09-01
Cesarean delivery adhesions, during laparoscopic hysterectomy, can present surgical challenges, including distortion of anatomy, prolonged operating time, and inadvertent injury to nearby structures. At the time of laparoscopic hysterectomy, in patients with significant adhesions from prior cesarean deliveries, we use a reverse inferior to superior vesicouterine fold dissection to mobilize the scarred bladder. We use this as an alternative to the commonly practiced technique of mobilizing the bladder in a superior to inferior fashion at the time of laparoscopic hysterectomy. Fifty-two patients with a median age of 42.5 years are presented. Forty-eight patients were discharged within 3-6 hours postoperatively. Sixteen patients were discharged with Foley catheters, because they were unable to void within the protocol for a fast-track discharge. The catheters were removed between postoperative days 1 and 5. There were no gastrointestinal or genitourinary complications. One patient experienced a delayed vaginal cuff abscess and bleeding, which were managed conservatively. Reverse vesicouterine fold dissection is a useful alternative technique for laparoscopic hysterectomy in women with a history of prior cesarean deliveries.
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.
PVIScreen extends the concepts of a prior model (BioVapor), which accounted for oxygen-driven biodegradation of multiple constituents of petroleum in the soil above the water table. Typically, the model is run 1000 times using various factors.
Medical Student Perspectives of Active Learning: A Focus Group Study.
Walling, Anne; Istas, Kathryn; Bonaminio, Giulia A; Paolo, Anthony M; Fontes, Joseph D; Davis, Nancy; Berardo, Benito A
2017-01-01
Phenomenon: Medical student perspectives were sought about active learning, including concerns, challenges, perceived advantages and disadvantages, and appropriate role in the educational process. Focus groups were conducted with students from all years and campuses of a large U.S. state medical school. Students had considerable experience with active learning prior to medical school and conveyed accurate understanding of the concept and its major strategies. They appreciated the potential of active learning to deepen and broaden learning and its value for long-term professional development but had significant concerns about the efficiency of the process, the clarity of expectations provided, and the importance of receiving preparatory materials. Most significantly, active learning experiences were perceived as disconnected from grading and even as impeding preparation for school and national examinations. Insights: Medical students understand the concepts of active learning and have considerable experience in several formats prior to medical school. They are generally supportive of active learning concepts but frustrated by perceived inefficiencies and lack of contribution to the urgencies of achieving optimal grades and passing United States Medical Licensing Examinations, especially Step 1.
Flexible Shields for Protecting Spacecraft Against Debris
NASA Technical Reports Server (NTRS)
Christiansen, Eric L.; Crews, Jeanne Lee
2004-01-01
A report presents the concept of Flexshield a class of versatile, lightweight, flexible shields for protecting spacecraft against impacts by small meteors and orbiting debris. The Flexshield concept incorporates elements of, but goes beyond, prior spacecraft-shielding concepts, including those of Whipple shields and, more recently, multi-shock shields and multi-shock blankets. A shield of the Flexshield type includes multiple outer layers (called bumpers in the art) made, variously, of advanced ceramic and/or polymeric fibers spaced apart from each other by a lightweight foam. As in prior such shields, the bumpers serve to shock an impinging hypervelocity particle, causing it to disintegrate vaporize, and spread out over a larger area so that it can be stopped by an innermost layer (back sheet). The flexibility of the fabric layers and compressibility of the foam make it possible to compress and fold the shield for transport, then deploy the shield for use. The shield can be attached to a spacecraft by use of snaps, hook-and-pile patches, or other devices. The shield can also contain multilayer insulation material, so that it provides some thermal protection in addition to mechanical protection.
The Effects of Globalization Phenomena on Educational Concepts
ERIC Educational Resources Information Center
Schrottner, Barbara Theresia
2010-01-01
It is becoming more and more apparent that globalization processes represent, theoretically as well as practically, a challenge for educational sciences and therefore, it must be addressed within the sphere of education. Accordingly, educational conceptions have to adapt to globalization phenomena and focus more on alternative and innovative…
ERIC Educational Resources Information Center
Mirhosseini, Seyyed-Abdolhamid; Ghafar Samar, Reza
2015-01-01
Mainstream trends of English language teaching (ELT) are predominantly constructed within the epistemological boundaries shaped by the traditional conceptions of linguistics, learning, and teaching as well as positivist research methodology. What tends to be overshadowed by such conceptions is the underlying foundational belief structure of ELT…
Spaceborne power systems preference analyses. Volume 1: Summary
NASA Technical Reports Server (NTRS)
Smith, J. H.; Feinberg, A.; Miles, R. F., Jr.
1985-01-01
Sixteen alternative spaceborne nuclear power system concepts were ranked using multiattribute decision analysis to identify promising concepts for further technology development. Four groups interviewed were: safety, systems definition and design, technology assessment, and mission analysis. The ranking results were consistent from group and for different utility function models for individuals.
Mapping out the Details: Supporting Struggling Writers' Written Expression with Concept Mapping
ERIC Educational Resources Information Center
Flanagan, Sara M.; Bouck, Emily C.
2015-01-01
Written expression is a key component of the secondary curriculum, but many students struggle to produce effective written expression passages. However, written expression can be supported through prewriting strategies such as concept mapping. Using a counterbalanced group design, 19 secondary students alternated between using paper- or…
Breezy Power: From Wind to Energy
ERIC Educational Resources Information Center
Claymier, Bob
2009-01-01
This lesson combines the science concepts of renewable energy and producing electricity with the technology concepts of design, constraints, and technology's impact on the environment. Over five class periods, sixth-grade students "work" for a fictitious power company as they research wind as an alternative energy source and design and test a…
Diagnosing Alternative Conceptions of Fermi Energy among Undergraduate Students
ERIC Educational Resources Information Center
Sharma, Sapna; Ahluwalia, Pardeep Kumar
2012-01-01
Physics education researchers have scientifically established the fact that the understanding of new concepts and interpretation of incoming information are strongly influenced by the preexisting knowledge and beliefs of students, called epistemological beliefs. This can lead to a gap between what students actually learn and what the teacher…
The Development of Preschoolers' Living Kinds Concept: A Longitudinal Study
ERIC Educational Resources Information Center
Margett-Jordan, Tessa; Falcon, Rachael G.; Witherington, David C.
2017-01-01
Given limitations in the integrative scope of past research, basic questions about the organization and development of preschoolers' living kinds concept remain open to debate. This study was designed to address past limitations through use of a longitudinal design, extensive stimulus set, and alternate indices of understanding. Thirty-five…