Sample records for problem involves determining

  1. Determination of optimal self-drive tourism route using the orienteering problem method

    NASA Astrophysics Data System (ADS)

    Hashim, Zakiah; Ismail, Wan Rosmanira; Ahmad, Norfaieqah

    2013-04-01

    This paper was conducted to determine the optimal travel routes for self-drive tourism based on the allocation of time and expense by maximizing the amount of attraction scores assigned to each city involved. Self-drive tourism represents a type of tourism where tourists hire or travel by their own vehicle. It only involves a tourist destination which can be linked with a network of roads. Normally, the traveling salesman problem (TSP) and multiple traveling salesman problems (MTSP) method were used in the minimization problem such as determination the shortest time or distance traveled. This paper involved an alternative approach for maximization method which is maximize the attraction scores and tested on tourism data for ten cities in Kedah. A set of priority scores are used to set the attraction score at each city. The classical approach of the orienteering problem was used to determine the optimal travel route. This approach is extended to the team orienteering problem and the two methods were compared. These two models have been solved by using LINGO12.0 software. The results indicate that the model involving the team orienteering problem provides a more appropriate solution compared to the orienteering problem model.

  2. Tracking problem solving by multivariate pattern analysis and Hidden Markov Model algorithms.

    PubMed

    Anderson, John R

    2012-03-01

    Multivariate pattern analysis can be combined with Hidden Markov Model algorithms to track the second-by-second thinking as people solve complex problems. Two applications of this methodology are illustrated with a data set taken from children as they interacted with an intelligent tutoring system for algebra. The first "mind reading" application involves using fMRI activity to track what students are doing as they solve a sequence of algebra problems. The methodology achieves considerable accuracy at determining both what problem-solving step the students are taking and whether they are performing that step correctly. The second "model discovery" application involves using statistical model evaluation to determine how many substates are involved in performing a step of algebraic problem solving. This research indicates that different steps involve different numbers of substates and these substates are associated with different fluency in algebra problem solving. Copyright © 2011 Elsevier Ltd. All rights reserved.

  3. Rocks in a Box: A Three-Point Problem.

    ERIC Educational Resources Information Center

    Leyden, Michael B.

    1981-01-01

    Describes a simulation drilling core activity involving the use of a physical model from which students gather data and solve a three-point problem to determine the strike and dip of a buried stratum. Includes descriptions of model making, data plots, and additional problems involving strike and dip. (DS)

  4. Paternal ADHD symptoms and child conduct problems: is father involvement always beneficial?

    PubMed

    Romirowsky, A M; Chronis-Tuscano, A

    2014-09-01

    Maternal psychopathology robustly predicts poor developmental and treatment outcomes for children with attention-deficit/hyperactivity disorder (ADHD). Despite the high heritability of ADHD, few studies have examined associations between paternal ADHD symptoms and child adjustment, and none have also considered degree of paternal involvement in childrearing. Identification of modifiable risk factors for child conduct problems is particularly important in this population given the serious adverse outcomes resulting from this comorbidity. This cross-sectional study examined the extent to which paternal involvement in childrearing moderated the association between paternal ADHD symptoms and child conduct problems among 37 children with ADHD and their biological fathers. Neither paternal ADHD symptoms nor involvement was independently associated with child conduct problems. However, the interaction between paternal ADHD symptoms and involvement was significant, such that paternal ADHD symptoms were positively associated with child conduct problems only when fathers were highly involved in childrearing. The presence of adult ADHD symptoms may determine whether father involvement in childrearing has a positive or detrimental influence on comorbid child conduct problems.

  5. Association between school bullying levels/types and mental health problems among Taiwanese adolescents.

    PubMed

    Yen, Cheng-Fang; Yang, Pinchen; Wang, Peng-Wei; Lin, Huang-Chi; Liu, Tai-Ling; Wu, Yu-Yu; Tang, Tze-Chun

    2014-04-01

    Few studies have compared the risks of mental health problems among the adolescents with different levels and different types of bullying involvement experiences. Bullying involvement in 6,406 adolescents was determined through use of the Chinese version of the School Bullying Experience Questionnaire. Data were collected regarding the mental health problems, including depression, suicidality, insomnia, general anxiety, social phobia, alcohol abuse, inattention, and hyperactivity/impulsivity. The association between experiences of bullying involvement and mental health problems was examined. The risk of mental health problems was compared among those with different levels/types of bullying involvement. The results found that being a victim of any type of bullying and being a perpetrator of passive bullying were significantly associated with all kinds of mental health problems, and being a perpetrator of active bullying was significantly associated with all kinds of mental health problems except for general anxiety. Victims or perpetrators of both passive and active bullying had a greater risk of some dimensions of mental health problems than those involved in only passive or active bullying. Differences in the risk of mental health problems were also found among adolescents involved in different types of bullying. This difference in comorbid mental health problems should be taken into consideration when assessing adolescents involved in different levels/types of bullying. © 2014.

  6. Self-Determination and Student Involvement in Functional Assessment: Innovative Practices

    ERIC Educational Resources Information Center

    Wehmeyer, Michael L.; Baker, Daniel J.; Blumberg, Richard; Harrison, Richard

    2004-01-01

    The fundamental feature that distinguishes positive behavior support (PBS) from previous generations of applied behavior analysis is its focus on the remediation of deficient contexts that are determined to be the source of the problem. Determining this source involves conducting a functional assessment. This innovative practices article presents…

  7. Paternal ADHD Symptoms and Child Conduct Problems: Is Father Involvement Always Beneficial?

    PubMed Central

    Romirowsky, Abigail Mintz; Chronis-Tuscano, Andrea

    2013-01-01

    Background Maternal psychopathology robustly predicts poor developmental and treatment outcomes for children with attention-deficit/hyperactivity disorder (ADHD). Despite the high heritability of ADHD, few studies have examined associations between paternal ADHD symptoms and child adjustment, and none have also considered degree of paternal involvement in childrearing. Identification of modifiable risk factors for child conduct problems is particularly important in this population given the serious adverse outcomes resulting from this comorbidity. Methods This cross-sectional study examined the extent to which paternal involvement in childrearing moderated the association between paternal ADHD symptoms and child conduct problems among 37 children with ADHD and their biological fathers. Results Neither paternal ADHD symptoms nor involvement was independently associated with child conduct problems. However, the interaction between paternal ADHD symptoms and involvement was significant, such that paternal ADHD symptoms were positively associated with child conduct problems only when fathers were highly involved in childrearing. Conclusions The presence of adult ADHD symptoms may determine whether father involvement in childrearing has a positive or detrimental influence on comorbid child conduct problems. PMID:25250402

  8. Adjustment, Performance, and Involvement of College Students with Disabilities.

    ERIC Educational Resources Information Center

    Kroeger, Sue; Scalia, Vincent

    1988-01-01

    Examined group of disabled college students (N=50) to determine whether psychosocial problems exist with these students and, if so, whether these problems can predict academic performance/involvement. Results indicated subjects were less disturbed than normative group, did not differ in body attitudes, and were more distorted on beliefs leading to…

  9. Problem solving therapy - use and effectiveness in general practice.

    PubMed

    Pierce, David

    2012-09-01

    Problem solving therapy (PST) is one of the focused psychological strategies supported by Medicare for use by appropriately trained general practitioners. This article reviews the evidence base for PST and its use in the general practice setting. Problem solving therapy involves patients learning or reactivating problem solving skills. These skills can then be applied to specific life problems associated with psychological and somatic symptoms. Problem solving therapy is suitable for use in general practice for patients experiencing common mental health conditions and has been shown to be as effective in the treatment of depression as antidepressants. Problem solving therapy involves a series of sequential stages. The clinician assists the patient to develop new empowering skills, and then supports them to work through the stages of therapy to determine and implement the solution selected by the patient. Many experienced GPs will identify their own existing problem solving skills. Learning about PST may involve refining and focusing these skills.

  10. Attributes Heeded When Representing an Osmosis Problem.

    ERIC Educational Resources Information Center

    Zuckerman, June Trop

    Eighteen high school science students were involved in a study to determine what attributes in the problem statement they need when representing a typical osmosis problem. In order to realize this goal students were asked to solve problems aloud and to explain their answers. Included as a part of the results are the attributes that the students…

  11. REACTT: an algorithm for solving spatial equilibrium problems.

    Treesearch

    D.J. Brooks; J. Kincaid

    1987-01-01

    The problem of determining equilibrium prices and quantities in spatially separated markets is reviewed. Algorithms that compute spatial equilibria are discussed. A computer program using the reactive programming algorithm for solving spatial equilibrium problems that involve multiple commodities is presented, along with detailed documentation. A sample data set,...

  12. A TECHNIQUE FOR DETERMINING THE OPERATING CAPACITIES OF JUNIOR COLLEGE INSTRUCTIONAL FACILITIES.

    ERIC Educational Resources Information Center

    CLAWSON, KENNETH TED

    A TECHNIQUE FOR DETERMINING THE CAPACITY OF A COLLEGE PLANT SHOULD (1) CONSIDER THE FUNCTIONAL USE OF THE PLANT, (2) ATTACK THE CAPACITY PROBLEM DIRECTLY RATHER THAN THROUGH STATUS STUDIES, (3) INVOLVE THE SIGNIFICANT FACTORS RELATED TO CAPACITY, (4) USE OBJECTIVE FACTORS, (5) BE UNIVERSAL IN ITS APPLICATION, (6) NOT INVOLVE ABSTRACT STANDARDS,…

  13. Games and gambling involvement among casino patrons.

    PubMed

    LaPlante, Debi A; Afifi, Tracie O; Shaffer, Howard J

    2013-06-01

    A growing literature is addressing the nature of the relationships among gambling activity, gambling involvement, and gambling-related problems. This research suggests that among the general population, compared to playing any specific game, gambling involvement is a better predictor of gambling-related problems. To date, researchers have not examined these relationships among casino patrons, a population that differs from the general population in a variety of important ways. A survey of 1160 casino patrons at two Las Vegas resort casinos allowed us to determine relationships between the games that patrons played during the 12 months before their casino visit, the games that patrons played during their casino visit, and patrons' self-perceived history of gambling-related problems. Results indicate that playing specific gambling games onsite predicted (i.e., statistically significant odds ratios ranging from .5 to 4.51) self-perceived gambling-related problems. However, after controlling for involvement, operationally defined as the number of games played during the current casino visit and self-reported gambling frequency during the past 12 months, the relationships between games and gambling-related problems disappeared or were attenuated (i.e., odds ratios no longer statistically significant). These results extend the burgeoning literature related to gambling involvement and its relationship to gambling-related problems.

  14. Basic research and data analysis for the national geodetic satellite program and for the earth and ocean physics applications program

    NASA Technical Reports Server (NTRS)

    1974-01-01

    Activities related to the National Geodetic Satellite Program are reported and include a discussion of Ohio State University's OSU275 set of tracking station coordinates and transformation parameters, determination of network distortions, and plans for data acquisition and processing. The problems encountered in the development of the LAGEOS satellite are reported in an account of activities related to the Earth and Ocean Physics Applications Program. The LAGEOS problem involves transmission and reception of the laser pulse designed to make accurate determinations of the earth's crustal and rotational motions. Pulse motion, ephemeris, arc range measurements, and accuracy estimates are discussed in view of the problem. Personnel involved in the two programs are also listed, along with travel activities and reports published to date.

  15. Diverse knowledges and competing interests: an essay on socio-technical problem-solving.

    PubMed

    di Norcia, Vincent

    2002-01-01

    Solving complex socio-technical problems, this paper claims, involves diverse knowledges (cognitive diversity), competing interests (social diversity), and pragmatism. To explain this view, this paper first explores two different cases: Canadian pulp and paper mill pollution and siting nuclear reactors in systematically sensitive areas of California. Solving such socio-technically complex problems involves cognitive diversity as well as social diversity and pragmatism. Cognitive diversity requires one to not only recognize relevant knowledges but also to assess their validity. Finally, it is suggested, integrating the resultant set of diverse relevant and valid knowledges determines the parameters of the solution space for the problem.

  16. Non-Mathematical Problem Solving in Organic Chemistry

    ERIC Educational Resources Information Center

    Cartrette, David P.; Bodner, George M.

    2010-01-01

    Differences in problem-solving ability among organic chemistry graduate students and faculty were studied within the domain of problems that involved the determination of the structure of a molecule from the molecular formula of the compound and a combination of IR and [to the first power]H NMR spectra. The participants' performance on these tasks…

  17. Predictors of involvement in the juvenile justice system among psychiatric hospitalized adolescents.

    PubMed

    Cropsey, Karen L; Weaver, Michael F; Dupre, Madeleine A

    2008-07-01

    Several risk factors for juvenile justice involvement have been identified in previous research among delinquents and include mental illness, substance use, trauma and abuse, family dysfunction, poor parenting, school problems, and aggressive behavior. However, most of these predictors resulted from studies among adolescents incarcerated in the juvenile justice system. We were interested in finding out the prevalence rates of juvenile justice involvement among psychiatric inpatient adolescents and determining predictors of juvenile justice involvement in this high-risk group. Six hundred and thirty-six medical records from adolescents ages 12-17 years who were consecutively admitted to one of two psychiatric inpatient units between July 1, 2003 and June 30, 2004 were examined. Almost half (43.6%) of hospitalized adolescents had a history of juvenile justice involvement. Logistic regression analysis was conducted to determine predictors of juvenile justice involvement. Significant predictors of juvenile justice involvement included being male, parental legal history, family substance abuse history, disruptive disorder, cocaine use, being sexually active, and having a history of aggressive behavior. Adolescents in mental health or substance abuse treatment settings should be screened for juvenile justice involvement and appropriate referrals made to prevent worsening problems for at-risk youth.

  18. Analysis of general aviation single-pilot IFR incident data obtained from the NASA aviation safety reporting system

    NASA Technical Reports Server (NTRS)

    Bergeron, H. P.

    1980-01-01

    Data obtained from the NASA Aviation Safety Reporting System (ASRS) data base were used to determine problems in general aviation single pilot IFR operations. The data examined consisted of incident reports involving flight safety in the National Aviation System. Only those incidents involving general aviation fixed wing aircraft flying under IFR in instrument meteorological conditions were analyzed. The data were cataloged into one of five major problem areas: (1) controller judgement and response problems; (2) pilot judgement and response problems; (3) air traffic control intrafacility and interfacility conflicts; (4) ATC and pilot communications problems; and (5) IFR-VFR conflicts. The significance of the related problems, and the various underlying elements associated with each are discussed. Previous ASRS reports covering several areas of analysis are reviewed.

  19. An Optimization Model for Scheduling Problems with Two-Dimensional Spatial Resource Constraint

    NASA Technical Reports Server (NTRS)

    Garcia, Christopher; Rabadi, Ghaith

    2010-01-01

    Traditional scheduling problems involve determining temporal assignments for a set of jobs in order to optimize some objective. Some scheduling problems also require the use of limited resources, which adds another dimension of complexity. In this paper we introduce a spatial resource-constrained scheduling problem that can arise in assembly, warehousing, cross-docking, inventory management, and other areas of logistics and supply chain management. This scheduling problem involves a twodimensional rectangular area as a limited resource. Each job, in addition to having temporal requirements, has a width and a height and utilizes a certain amount of space inside the area. We propose an optimization model for scheduling the jobs while respecting all temporal and spatial constraints.

  20. Enhanced Decision Analysis Support System.

    DTIC Science & Technology

    1981-03-01

    autorrares "i., the method for determining preferences when multiple and competing attributes are involved. Worth assessment is used as the model which...1967 as a method for determining preferenoe when multiple and competing attributes are involved (Rf 10). The tern worth can be - equated to other... competing objectives. After some discussion, the group decided that the problem could best be decided using the worth assessment procedure. They

  1. On the interaction of a vibrating plate with an acoustic medium

    NASA Technical Reports Server (NTRS)

    Mixson, J. S.; Koval, L. R.

    1974-01-01

    The interaction of a vibrating plate with an adjacent acoustic medium is important in problems involving the radiation of sound from panels, in problems involving the transmission of sound through walls of buildings, aircraft, or launch vehicles; and in problems involving the estimation of damping and the stress amplitude of vibration for panel-fatigue predictions. There appear to have been no systematic studies of the effects on the plate of fluid coupling for an arbitrary fluid-mass/plate-mass loading ratio. An attempt is made to determine this effect for a wide range of fluid-plate mass ratios without resorting to the usual simplifications of light or heavy fluid loading. Emphasis is with the plate motion rather than the radiation of sound.

  2. Video-Based Intervention in Teaching Fraction Problem-Solving to Students with Autism Spectrum Disorder

    ERIC Educational Resources Information Center

    Yakubova, Gulnoza; Hughes, Elizabeth M.; Hornberger, Erin

    2015-01-01

    The purpose of this study was to determine the effectiveness of a point-of-view video modeling intervention to teach mathematics problem-solving when working on word problems involving subtracting mixed fractions with uncommon denominators. Using a multiple-probe across students design of single-case methodology, three high school students with…

  3. A Comparative Study of Involvement and Motivation among Casino Gamblers.

    PubMed

    Lee, Choong-Ki; Lee, Bongkoo; Bernhard, Bo Jason; Lee, Tae Kyung

    2009-09-01

    The purpose of this paper is to investigate three different types of gamblers (which we label "non-problem", "some problem", and "probable pathological gamblers") to determine differences in involvement and motivation, as well as differences in demographic and behavioral variables. The analysis takes advantage of a unique opportunity to sample on-site at a major casino in South Korea, and the resulting purposive sample yielded 180 completed questionnaires in each of the three groups, for a total number of 540. Factor analysis, analysis of variance (ANOVA) and Duncan tests, and Chi-square tests are employed to analyze the data collected from the survey. Findings from ANOVA tests indicate that involvement factors of importance/self-expression, pleasure/interest, and centrality derived from the factor analysis were significantly different among these three types of gamblers. The "probable pathological" and "some problem" gamblers were found to have similar degrees of involvement, and higher degrees of involvement than the non-problem gamblers. The tests also reveal that motivational factors of escape, socialization, winning, and exploring scenery were significantly different among these three types of gamblers. When looking at motivations to visit the casino, "probable pathological" gamblers were more likely to seek winning, the "some problem" group appeared to be more likely to seek escape, and the "non-problem" gamblers indicate that their motivations to visit centered around explorations of scenery and culture in the surrounding casino area. The tools for exploring motivations and involvements of gambling provide valuable and discerning information about the entire spectrum of gamblers.

  4. An examination of gender bias on the eighth-grade MEAP science test as it relates to the Hunter Gatherer Theory of Spatial Sex Differences

    NASA Astrophysics Data System (ADS)

    Armstrong-Hall, Judy Gail

    The purpose of this study was to apply the Hunter-Gatherer Theory of sex spatial skills to responses to individual questions by eighth grade students on the Science component of the Michigan Educational Assessment Program (MEAP) to determine if sex bias was inherent in the test. The Hunter-Gatherer Theory on Spatial Sex Differences, an original theory, that suggested a spatial dimorphism concept with female spatial skill of pattern recall of unconnected items and male spatial skills requiring mental movement. This is the first attempt to apply the Hunter-Gatherer Theory on Spatial Sex Differences to a standardized test. An overall hypothesis suggested that the Hunter-Gatherer Theory of Spatial Sex Differences could predict that males would perform better on problems involving mental movement and females would do better on problems involving the pattern recall of unconnected items. Responses to questions on the 1994-95 MEAP requiring the use of male spatial skills and female spatial skills were analyzed for 5,155 eighth grade students. A panel composed of five educators and a theory developer determined which test items involved the use of male and female spatial skills. A MANOVA, using a random sample of 20% of the 5,155 students to compare male and female correct scores, was statistically significant, with males having higher scores on male spatial skills items and females having higher scores on female spatial skills items. Pearson product moment correlation analyses produced a positive correlation for both male and female performance on both types of spatial skills. The Hunter-Gatherer Theory of Spatial Sex Differences appears to be able to predict that males could perform better on the problems involving mental movement and females could perform better on problems involving the pattern recall of unconnected items. Recommendations for further research included: examination of male/female spatial skill differences at early elementary and high school levels to determine impact of gender on difficulties in solving spatial problems; investigation of the relationship between dominant female spatial skills for students diagnosed with ADHD; study effects of teaching male spatial skills to female students starting in early elementary school to determine the effect on standardized testing.

  5. Exact solution of three-dimensional transport problems using one-dimensional models. [in semiconductor devices

    NASA Technical Reports Server (NTRS)

    Misiakos, K.; Lindholm, F. A.

    1986-01-01

    Several parameters of certain three-dimensional semiconductor devices including diodes, transistors, and solar cells can be determined without solving the actual boundary-value problem. The recombination current, transit time, and open-circuit voltage of planar diodes are emphasized here. The resulting analytical expressions enable determination of the surface recombination velocity of shallow planar diodes. The method involves introducing corresponding one-dimensional models having the same values of these parameters.

  6. Optical Sensor/Actuator Locations for Active Structural Acoustic Control

    NASA Technical Reports Server (NTRS)

    Padula, Sharon L.; Palumbo, Daniel L.; Kincaid, Rex K.

    1998-01-01

    Researchers at NASA Langley Research Center have extensive experience using active structural acoustic control (ASAC) for aircraft interior noise reduction. One aspect of ASAC involves the selection of optimum locations for microphone sensors and force actuators. This paper explains the importance of sensor/actuator selection, reviews optimization techniques, and summarizes experimental and numerical results. Three combinatorial optimization problems are described. Two involve the determination of the number and position of piezoelectric actuators, and the other involves the determination of the number and location of the sensors. For each case, a solution method is suggested, and typical results are examined. The first case, a simplified problem with simulated data, is used to illustrate the method. The second and third cases are more representative of the potential of the method and use measured data. The three case studies and laboratory test results establish the usefulness of the numerical methods.

  7. Association Between Anticipatory Grief and Problem Solving Among Family Caregivers of Persons with Cognitive Impairment

    PubMed Central

    Fowler, Nicole R.; Hansen, Alexandra S.; Barnato, Amber E.; Garand, Linda

    2013-01-01

    Objective Measure perceived involvement in medical decision making and determine if anticipatory grief is associated with problem solving among family caregivers of older adults with cognitive impairment. Method Retrospective analysis of baseline data from a caregiver intervention (n=73). Multivariable regression models testing the association between caregivers’ anticipatory grief, measured by the Anticipatory Grief Scale (AGS), with problem solving abilities, measured by the Social Problem Solving Inventory – Revised: Short Form (SPSI-R: S). Results 47/73 (64%) of caregivers reported involvement in medical decision making. Mean AGS was 70.1 (± 14.8) and mean SPSI-R:S was 107.2 (± 11.6). Higher AGS scores were associated with lower positive problem orientation (P=0.041) and higher negative problem orientation scores (P=0.001) but not other components of problem solving- rational problem solving, avoidance style, and impulsivity/carelessness style. Discussion Higher anticipatory grief among family caregivers impaired problem solving, which could have negative consequences for their medical decision making responsibilities. PMID:23428394

  8. Adolescent Involvement in Discipline Decision Making

    ERIC Educational Resources Information Center

    Deroma, Virginia M.; Lassiter, Kerry S.; Davis, Virginia A.

    2004-01-01

    This study examined the influence of (a) low, medium, or high adolescent involvement (degree to which adolescent input was solicited in determining consequence) in discipline decisions and (b) parental versus adolescent focus of impact of behavior problem (parent emphasized inconvenience to either self or adolescent). After viewing videotaped…

  9. Copyright: A Guide for Public Humanities Projects. Federation Resources 3.

    ERIC Educational Resources Information Center

    Rozeen, Mark

    As public humanities programs increasingly make use of media products, an understanding of copyrights is essential. Some problems pertaining to copyrights may be alleviated by advanced planning, a clear division of responsibilities, and by using reason to determine that policies are workable and fair. The problem involves a growing…

  10. Remote sensing of the Earth from Space: A program in crisis

    NASA Technical Reports Server (NTRS)

    1985-01-01

    The present situation in earth remote sensing, determining why certain problems exist, and trying to find out what can be done to solve these problems are discussed. The conclusion is that operational remote sensing is in disarray. The difficulties involve policy and institutional issues. Recommendations are given.

  11. What Type of Communication during Conflict is Beneficial for Intimate Relationships?

    PubMed Central

    Overall, Nickola C.; McNulty, James K.

    2016-01-01

    What constitutes effective communication during conflict? Answering this question requires (a) clarifying whether communication expresses opposition versus cooperation and is direct versus indirect, (b) assessing the mechanisms through which communication effects relationships, and (c) identifying the contextual factors that determine the impact of communication. Recent research incorporating these components illustrates that direct opposition is beneficial when serious problems need to be addressed and partners are able to change, but can be harmful when partners are not confident or secure enough to be responsive. In contrast, cooperative communication involving affection and validation can be harmful when serious problems need to changed, but may be beneficial when problems are minor, cannot be changed, or involve partners whose defensiveness curtails problem solving. PMID:28025652

  12. Relationship between Mental Models Related to the Particulate Nature of Matter and the Infinite Nature of Geometrical Figures.

    ERIC Educational Resources Information Center

    Tirosh, Dina; Stavy, Ruth

    A study was conducted in Israel to determine effects of external similarity in problem structure on students' responses. Fifty students from each of the 7th, 8th, 10th, and 12th grade levels were presented with three problems involving successive divisions that were similar in structure. The problems asked separately whether the processes of…

  13. Pythagorean fuzzy analytic hierarchy process to multi-criteria decision making

    NASA Astrophysics Data System (ADS)

    Mohd, Wan Rosanisah Wan; Abdullah, Lazim

    2017-11-01

    A numerous approaches have been proposed in the literature to determine the criteria of weight. The weight of criteria is very significant in the process of decision making. One of the outstanding approaches that used to determine weight of criteria is analytic hierarchy process (AHP). This method involves decision makers (DMs) to evaluate the decision to form the pair-wise comparison between criteria and alternatives. In classical AHP, the linguistic variable of pairwise comparison is presented in terms of crisp value. However, this method is not appropriate to present the real situation of the problems because it involved the uncertainty in linguistic judgment. For this reason, AHP has been extended by incorporating the Pythagorean fuzzy sets. In addition, no one has found in the literature proposed how to determine the weight of criteria using AHP under Pythagorean fuzzy sets. In order to solve the MCDM problem, the Pythagorean fuzzy analytic hierarchy process is proposed to determine the criteria weight of the evaluation criteria. Using the linguistic variables, pairwise comparison for evaluation criteria are made to the weights of criteria using Pythagorean fuzzy numbers (PFNs). The proposed method is implemented in the evaluation problem in order to demonstrate its applicability. This study shows that the proposed method provides us with a useful way and a new direction in solving MCDM problems with Pythagorean fuzzy context.

  14. A Comparative Study of Involvement and Motivation among Casino Gamblers

    PubMed Central

    Lee, Choong-Ki; Lee, BongKoo; Bernhard, Bo Jason

    2009-01-01

    Objective The purpose of this paper is to investigate three different types of gamblers (which we label "non-problem", "some problem", and "probable pathological gamblers") to determine differences in involvement and motivation, as well as differences in demographic and behavioral variables. Methods The analysis takes advantage of a unique opportunity to sample on-site at a major casino in South Korea, and the resulting purposive sample yielded 180 completed questionnaires in each of the three groups, for a total number of 540. Factor analysis, analysis of variance (ANOVA) and Duncan tests, and Chi-square tests are employed to analyze the data collected from the survey. Results Findings from ANOVA tests indicate that involvement factors of importance/self-expression, pleasure/interest, and centrality derived from the factor analysis were significantly different among these three types of gamblers. The "probable pathological" and "some problem" gamblers were found to have similar degrees of involvement, and higher degrees of involvement than the non-problem gamblers. The tests also reveal that motivational factors of escape, socialization, winning, and exploring scenery were significantly different among these three types of gamblers. When looking at motivations to visit the casino, "probable pathological" gamblers were more likely to seek winning, the "some problem" group appeared to be more likely to seek escape, and the "non-problem" gamblers indicate that their motivations to visit centered around explorations of scenery and culture in the surrounding casino area. Conclusion The tools for exploring motivations and involvements of gambling provide valuable and discerning information about the entire spectrum of gamblers. PMID:20046388

  15. Video-Based Intervention in Teaching Fraction Problem-Solving to Students with Autism Spectrum Disorder.

    PubMed

    Yakubova, Gulnoza; Hughes, Elizabeth M; Hornberger, Erin

    2015-09-01

    The purpose of this study was to determine the effectiveness of a point-of-view video modeling intervention to teach mathematics problem-solving when working on word problems involving subtracting mixed fractions with uncommon denominators. Using a multiple-probe across students design of single-case methodology, three high school students with ASD completed the study. All three students demonstrated greater accuracy in solving fraction word problems and maintained accuracy levels at a 1-week follow-up.

  16. (Fish) Food for Thought: Authority Shifts in the Interaction between Mathematics and Reality

    ERIC Educational Resources Information Center

    Peled, Irit

    2010-01-01

    This theoretical paper explores the decision-making process involved in modelling and mathematizing situations during problem solving. Specifically, it focuses on the authority behind these choices (i.e., what or who determines the chosen mathematical models). We show that different types of situations involve different sources of authority,…

  17. On the identification of a harmonic force on a viscoelastic plate from response data

    NASA Technical Reports Server (NTRS)

    D'Cruz, J.; Crisp, J. D. C.; Ryall, T. G.

    1992-01-01

    The problem of determining the force acting on a structure from measurements of the response of the structure to the force is an inverse problem. Presented is a method for determining the location, magnitude, and phase of a harmonic point force acting on a simply-supported classical viscoelastic rectangular plate from a number of displacement readings at discrete points on the plate. Presented also is a demonstration of the robustness of the solution technique to the effects of measurement noise as well as a means by which problems involving more general structural and loading configurations may be solved.

  18. Communication Problems for Patients Hospitalized with Chest Pain

    PubMed Central

    Simon, Steven R.; Lee, Thomas H.; Goldman, Lee; McDonough, Allison L.; Pearson, Steven D.

    1998-01-01

    In many settings, primary care physicians have begun to delegate inpatient care to hospitalists, but the impact of this change on patients' hospital experience is unknown. To determine the effect on physician-patient communication of having the regular outpatient physician (continuity physician) continue involvement in hospital care, we surveyed 1,059 consecutive patients hospitalized with chest pain. Patients whose continuity physicians remained involved in their hospital care were less likely to report communication problems regarding tests (20% vs 31%, p = .03), activity after discharge (42% vs 51%, p = .02), and health habits (31% vs 38%, p = .07). In a setting without a designated hospitalist system, communication problems were less frequent among patients whose continuity physicians were involved in their hospital care. New models of inpatient care delivery can maintain patient satisfaction but to do so must focus attention on improving physician-patient communication. PMID:9844081

  19. Computer program determines chemical composition of physical system at equilibrium

    NASA Technical Reports Server (NTRS)

    Kwong, S. S.

    1966-01-01

    FORTRAN 4 digital computer program calculates equilibrium composition of complex, multiphase chemical systems. This is a free energy minimization method with solution of the problem reduced to mathematical operations, without concern for the chemistry involved. Also certain thermodynamic properties are determined as byproducts of the main calculations.

  20. A Simplified Technique for Evaluating Human "CCR5" Genetic Polymorphism

    ERIC Educational Resources Information Center

    Falteisek, Lukáš; Cerný, Jan; Janštová, Vanda

    2013-01-01

    To involve students in thinking about the problem of AIDS (which is important in the view of nondecreasing infection rates), we established a practical lab using a simplified adaptation of Thomas's (2004) method to determine the polymorphism of HIV co-receptor CCR5 from students' own epithelial cells. CCR5 is a receptor involved in inflammatory…

  1. Determining a carbohydrate profile for Hansenula polymorpha

    NASA Technical Reports Server (NTRS)

    Petersen, G. R.

    1985-01-01

    The determination of the levels of carbohydrates in the yeast Hansenula polymorpha required the development of new analytical procedures. Existing fractionation and analytical methods were adapted to deal with the problems involved with the lysis of whole cells. Using these new procedures, the complete carbohydrate profiles of H. polymorpha and selected mutant strains were determined and shown to correlate favourably with previously published results.

  2. Hybrid Genetic Agorithms and Line Search Method for Industrial Production Planning with Non-Linear Fitness Function

    NASA Astrophysics Data System (ADS)

    Vasant, Pandian; Barsoum, Nader

    2008-10-01

    Many engineering, science, information technology and management optimization problems can be considered as non linear programming real world problems where the all or some of the parameters and variables involved are uncertain in nature. These can only be quantified using intelligent computational techniques such as evolutionary computation and fuzzy logic. The main objective of this research paper is to solve non linear fuzzy optimization problem where the technological coefficient in the constraints involved are fuzzy numbers which was represented by logistic membership functions by using hybrid evolutionary optimization approach. To explore the applicability of the present study a numerical example is considered to determine the production planning for the decision variables and profit of the company.

  3. Extraction of a group-pair relation: problem-solving relation from web-board documents.

    PubMed

    Pechsiri, Chaveevan; Piriyakul, Rapepun

    2016-01-01

    This paper aims to extract a group-pair relation as a Problem-Solving relation, for example a DiseaseSymptom-Treatment relation and a CarProblem-Repair relation, between two event-explanation groups, a problem-concept group as a symptom/CarProblem-concept group and a solving-concept group as a treatment-concept/repair concept group from hospital-web-board and car-repair-guru-web-board documents. The Problem-Solving relation (particularly Symptom-Treatment relation) including the graphical representation benefits non-professional persons by supporting knowledge of primarily solving problems. The research contains three problems: how to identify an EDU (an Elementary Discourse Unit, which is a simple sentence) with the event concept of either a problem or a solution; how to determine a problem-concept EDU boundary and a solving-concept EDU boundary as two event-explanation groups, and how to determine the Problem-Solving relation between these two event-explanation groups. Therefore, we apply word co-occurrence to identify a problem-concept EDU and a solving-concept EDU, and machine-learning techniques to solve a problem-concept EDU boundary and a solving-concept EDU boundary. We propose using k-mean and Naïve Bayes to determine the Problem-Solving relation between the two event-explanation groups involved with clustering features. In contrast to previous works, the proposed approach enables group-pair relation extraction with high accuracy.

  4. Operational applications of satellite snowcover observations in Rio Grande drainage of Colorado

    NASA Technical Reports Server (NTRS)

    Washicheck, J. N.; Mikesell, T.

    1975-01-01

    Various mapping techniques were tried and evaluated. There were many problems encountered such as distinquishing clouds from snow and snow under trees. A partial solution to some of the problems involves ground reconnaissance and low air flights. Snow areas, cloud cover, and total areas were planimetered after transferring imagery by use of zoom transfer scope. These determinations were then compared to areas determined by use of a density slicer. Considerable adjustment is required for these two values to compare. NOAA pictures were also utilized in the evaluation. Forest cover is one of the parameters used in the modeling process. The determination of this percentage is being explored.

  5. Solving magnetostatic field problems with NASTRAN

    NASA Technical Reports Server (NTRS)

    Hurwitz, M. M.; Schroeder, E. A.

    1978-01-01

    Determining the three-dimensional magnetostatic field in current-induced situations has usually involved vector potentials, which can lead to excessive computational times. How such magnetic fields may be determined using scalar potentials is reviewed. It is shown how the heat transfer capability of NASTRAN level 17 was modified to take advantage of the new method.

  6. Job Enrichment: Possible Criteria for Application in Air Force Organizations.

    ERIC Educational Resources Information Center

    Clarke, Richard L.; Pesenti, Peter T.

    The basic problem addressed by this thesis was the identification of specific criteria for determining the applicability of a job enrichment program in a specific career area. Identifying criteria involved the intrinsic and extrinsic aspects of a job, which act as determiners of job satisfaction or dissatisfaction. Survey data were obtained using…

  7. Assessment of PIV-based unsteady load determination of an airfoil with actuated flap

    NASA Astrophysics Data System (ADS)

    Sterenborg, J. J. H. M.; Lindeboom, R. C. J.; Simão Ferreira, C. J.; van Zuijlen, A. H.; Bijl, H.

    2014-02-01

    For complex experimental setups involving movable structures it is not trivial to directly measure unsteady loads. An alternative is to deduce unsteady loads indirectly from measured velocity fields using Noca's method. The ultimate aim is to use this method in future work to determine unsteady loads for fluid-structure interaction problems. The focus in this paper is first on the application and assessment of Noca's method for an airfoil with an oscillating trailing edge flap. To our best knowledge Noca's method has not been applied yet to airfoils with moving control surfaces or fluid-structure interaction problems. In addition, wind tunnel corrections for this type of unsteady flow problem are considered.

  8. Maternal addiction, child maladjustment and socio-demographic risks: implications for parenting behaviors

    PubMed Central

    SUCHMAN, NANCY E.; LUTHAR, SUNIYA S.

    2007-01-01

    Aims In this study we examined three parenting dimensions (involvement, autonomy, and limit-setting) and three potential determinants (maternal addiction, low SES and its correlates, and mothers’ perceptions of their children’s maladjustment) in order to disentangle features of parenting that are uniquely related to maternal addiction from those related to contextual determinants. We also examined conditional effects of low SES and its correlates on parenting. Design Based on a literature review and predictions arising from an ecological model of parenting, we expected that maternal addiction would be related with problems in parental involvement, but that the other parenting dimensions would be related with mothers’ perceptions of children’s maladjustment and low SES. Accordingly, we examined variance in each parenting dimensions accounted for by each of the three determinants, respectively. Participants Subjects included 120 (69 opiate-addicted and 51 SES-matched comparison) mothers with children under 16 years of age. Measurements Children’s maladaptive behavior was assessed with the Behavioral Assessment System for Children, and parental adjustment with the Parent Child Relationship Inventory. Findings Direct effect predictions were confirmed and two conditional effects involving single status and family size were also found. Conclusions Although many parenting problems have previously been attributed to maternal addiction, only parental involvement is directly related to being an addict; other parenting dimensions may be better explained by contextual factors. PMID:11048359

  9. The effect of continuous low dose-rate gamma irradiation on cell population kinetics of lymphoid tissue

    NASA Technical Reports Server (NTRS)

    Foster, B. R.

    1973-01-01

    The problem studied involved cell proliferation in mice thymus undergoing irradiation at a dose rate of 10 roetgens/day for 105 days. Specifically, the aim was to determine wheather or not a steady state of cell population can be established for the indicated period of time and what compensatory mechanisms of cell population are involved.

  10. Podiatric involvement in multidisciplinary falls-prevention clinics in Australia.

    PubMed

    Menz, Hylton B; Hill, Keith D

    2007-01-01

    Falls in older people are a major public health problem, and there is increasing evidence that foot problems and inappropriate footwear increase the risk of falls. Several multidisciplinary prevention clinics have been established to address the problem of falls; however, the role of podiatry in these clinics has not been clearly defined. The aims of this study were to determine the level of podiatric involvement in multidisciplinary falls clinics in Australia and to describe the assessments undertaken and interventions provided by podiatrists in these settings. A database of falls clinics was developed through consultation with departments of health in each state and territory. Clinic managers were contacted and surveyed as to whether the clinic incorporated podiatry services. If so, the podiatrists were contacted and asked to complete a brief questionnaire regarding their level of involvement and the assessment procedures and interventions offered. Of the 36 clinics contacted, 25 completed the survey. Only four of these clinics reported direct podiatric involvement. Despite the limited involvement of podiatry in these clinics, all of the clinic managers stated that they considered podiatry to have an important role to play in falls prevention. Podiatry service provision in falls clinics varied considerably in relation to eligibility criteria, assessments undertaken, and interventions provided. Despite the recognition that foot problems and inappropriate footwear are risk factors for falls, podiatry currently has a relatively minor and poorly defined role in multidisciplinary falls-prevention clinics in Australia.

  11. Our Professional Organizations and the Environmental Dilemma

    ERIC Educational Resources Information Center

    Granholm, Nels H.

    1972-01-01

    Summarizes the response by members of the Division of Invertebrate Zoologists of the American Society of Zoologists to a question determining their feelings toward involving the division in work toward resolving pressing ecological problems. (AL)

  12. Application of fuzzy theories to formulation of multi-objective design problems. [for helicopters

    NASA Technical Reports Server (NTRS)

    Dhingra, A. K.; Rao, S. S.; Miura, H.

    1988-01-01

    Much of the decision making in real world takes place in an environment in which the goals, the constraints, and the consequences of possible actions are not known precisely. In order to deal with imprecision quantitatively, the tools of fuzzy set theory can by used. This paper demonstrates the effectiveness of fuzzy theories in the formulation and solution of two types of helicopter design problems involving multiple objectives. The first problem deals with the determination of optimal flight parameters to accomplish a specified mission in the presence of three competing objectives. The second problem addresses the optimal design of the main rotor of a helicopter involving eight objective functions. A method of solving these multi-objective problems using nonlinear programming techniques is presented. Results obtained using fuzzy formulation are compared with those obtained using crisp optimization techniques. The outlined procedures are expected to be useful in situations where doubt arises about the exactness of permissible values, degree of credibility, and correctness of statements and judgements.

  13. Conjugate gradient based projection - A new explicit methodology for frictional contact

    NASA Technical Reports Server (NTRS)

    Tamma, Kumar K.; Li, Maocheng; Sha, Desong

    1993-01-01

    With special attention towards the applicability to parallel computation or vectorization, a new and effective explicit approach for linear complementary formulations involving a conjugate gradient based projection methodology is proposed in this study for contact problems with Coulomb friction. The overall objectives are focussed towards providing an explicit methodology of computation for the complete contact problem with friction. In this regard, the primary idea for solving the linear complementary formulations stems from an established search direction which is projected to a feasible region determined by the non-negative constraint condition; this direction is then applied to the Fletcher-Reeves conjugate gradient method resulting in a powerful explicit methodology which possesses high accuracy, excellent convergence characteristics, fast computational speed and is relatively simple to implement for contact problems involving Coulomb friction.

  14. Examining Factors in the Research Institute on Addictions Self-Inventory (RIASI): Associations with Alcohol Use and Problems at Assessment and Follow-Up

    PubMed Central

    Mann, Robert E.; Stoduto, Gina; Zalcman, Rosely Flam; Nochajski, Thomas H.; Hall, Louise; Dill, Patricia; Wells-Parker, Elisabeth

    2009-01-01

    Impaired driving is a leading cause of alcohol-related deaths and injuries. Rehabilitation or remedial programs, involving assessment and screening of convicted impaired drivers to determine problem severity and appropriate programs, are an important component of society’s response to this problem. Ontario’s remedial program, Back on Track (BOT), involves an assessment process that includes administration of the Research Institute on Addictions Self-Inventory (RIASI) to determine assignment to an education or treatment program. The purpose of this study is to identify factors within the RIASI and examine how factor scores are associated with alcohol use and problem indicators at assessment and six-month follow-up. The sample included 22,298 individuals who completed BOT from 2000 to 2005. Principal component factor analysis with varimax rotation was conducted on RIASI data and an eight factor solution was retained: (1) Negative Affect, (2) Sensation Seeking, (3) Alcohol-Quantity, (4) Social Conformity, (5) High Risk Lifestyle, (6) Alcohol Problems, (7) Interpersonal Competence, and (8) Family History. Regression analyses were conducted to examine associations between factors and alcohol and problem measures obtained at assessment and at follow-up. Most factors, except for Interpersonal Competence, were associated with more alcohol use and problems at assessment. A similar pattern was observed at 6-month follow-up, but interestingly some factors (Negative Affect, Sensation Seeking, Alcohol-Quantity and Family History) predicted fewer days of alcohol use. The Interpersonal Competence factor was associated with significantly lower levels of alcohol use and problems at both assessment and follow-up. This work suggests that the RIASI provides information on several domains that have important relationships with alcohol problem severity and outcomes. PMID:20049234

  15. Numerical Leak Detection in a Pipeline Network of Complex Structure with Unsteady Flow

    NASA Astrophysics Data System (ADS)

    Aida-zade, K. R.; Ashrafova, E. R.

    2017-12-01

    An inverse problem for a pipeline network of complex loopback structure is solved numerically. The problem is to determine the locations and amounts of leaks from unsteady flow characteristics measured at some pipeline points. The features of the problem include impulse functions involved in a system of hyperbolic differential equations, the absence of classical initial conditions, and boundary conditions specified as nonseparated relations between the states at the endpoints of adjacent pipeline segments. The problem is reduced to a parametric optimal control problem without initial conditions, but with nonseparated boundary conditions. The latter problem is solved by applying first-order optimization methods. Results of numerical experiments are presented.

  16. Application of modern control theory to scheduling and path-stretching maneuvers of aircraft in the near terminal area

    NASA Technical Reports Server (NTRS)

    Athans, M.

    1974-01-01

    A design concept of the dynamic control of aircraft in the near terminal area is discussed. An arbitrary set of nominal air routes, with possible multiple merging points, all leading to a single runway, is considered. The system allows for the automated determination of acceleration/deceleration of aircraft along the nominal air routes, as well as for the automated determination of path-stretching delay maneuvers. In addition to normal operating conditions, the system accommodates: (1) variable commanded separations over the outer marker to allow for takeoffs and between successive landings and (2) emergency conditions under which aircraft in distress have priority. The system design is based on a combination of three distinct optimal control problems involving a standard linear-quadratic problem, a parameter optimization problem, and a minimum-time rendezvous problem.

  17. Faculty Roles, Responsibilities, and Involvement in Campus Safety Initiatives as Perceived by Faculty and Administrators: A Case Study at a Large State University

    ERIC Educational Resources Information Center

    Rollings, Meda Janeen

    2010-01-01

    The study addressed the problem of campus safety and the extent to which faculty and administrators are aware of institutional security policies. Further, the research compared perceptions of administrators and faculty regarding faculty awareness of and involvement in campus safety policy initiatives. The research sought to determine if the…

  18. Simulating variable source problems via post processing of individual particle tallies

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

    Bleuel, D.L.; Donahue, R.J.; Ludewigt, B.A.

    2000-10-20

    Monte Carlo is an extremely powerful method of simulating complex, three dimensional environments without excessive problem simplification. However, it is often time consuming to simulate models in which the source can be highly varied. Similarly difficult are optimization studies involving sources in which many input parameters are variable, such as particle energy, angle, and spatial distribution. Such studies are often approached using brute force methods or intelligent guesswork. One field in which these problems are often encountered is accelerator-driven Boron Neutron Capture Therapy (BNCT) for the treatment of cancers. Solving the reverse problem of determining the best neutron source formore » optimal BNCT treatment can be accomplished by separating the time-consuming particle-tracking process of a full Monte Carlo simulation from the calculation of the source weighting factors which is typically performed at the beginning of a Monte Carlo simulation. By post-processing these weighting factors on a recorded file of individual particle tally information, the effect of changing source variables can be realized in a matter of seconds, instead of requiring hours or days for additional complete simulations. By intelligent source biasing, any number of different source distributions can be calculated quickly from a single Monte Carlo simulation. The source description can be treated as variable and the effect of changing multiple interdependent source variables on the problem's solution can be determined. Though the focus of this study is on BNCT applications, this procedure may be applicable to any problem that involves a variable source.« less

  19. Determinations of Carbon Dioxide by Titration: New Experiments for General, Physical, and Quantitative Analysis Courses.

    ERIC Educational Resources Information Center

    Crossno, S. K.; And Others

    1996-01-01

    Presents experiments involving the analysis of commercial products such as carbonated beverages and antacids that illustrate the principles of acid-base reactions and present interesting problems in stoichiometry for students. (JRH)

  20. Alcohol and pleasure boat operators

    DOT National Transportation Integrated Search

    1975-06-01

    This report presents an initial look at the involvement of alcohol in recreational boating. It attempts to identify a problem area. The report has three objectives: 1) to define drunkenness in small boating; 2) to describe a method of determining the...

  1. [Cyber-bullying in adolescents: associated psychosocial problems and comparison with school bullying].

    PubMed

    Kubiszewski, V; Fontaine, R; Huré, K; Rusch, E

    2013-04-01

    The aim of this study was to determine the prevalence of adolescents engaged in cyber-bullying and then to identify whether students involved in cyber- and school bullying present the same characteristics of internalizing problems (insomnia, perceived social disintegration, psychological distress) and externalizing problems (general aggressiveness, antisocial behavior). Semi-structured interviews were conducted with 738 adolescents from a high-school and a middle-school (mean age=14.8 ± 2.7). The Electronic Bullying Questionnaire and the Olweus Bully/Victim Questionnaire were used to identify profiles of cyber-bullying (cyber-victim, cyber-bully, cyber-bully/victim and cyber-neutral) and school bullying (victim, bully, bully/victim and neutral). Internalizing problems were investigated using the Athens Insomnia Scale, a Perceived Social Disintegration Scale and a Psychological Distress Scale. Externalizing problems were assessed using a General Aggressiveness Scale and an Antisocial Behavior Scale. Almost one student in four was involved in cyber-bullying (16.4% as cyber-victim, 4.9% as cyber-bully and 5.6% as cyber-bully/victim); 14% of our sample was engaged in school bullying as a victim, 7.2% as a bully and 2.8% as a bully/victim. The majority of adolescents involved in cyber-bullying were not involved in school bullying. With regard to the problems associated with school bullying, internalizing problems were more prevalent in victims and bully/victims, whereas externalizing problems were more common in bullies and bully/victims. A similar pattern was found in cyber-bullying where internalizing problems were characteristic of cyber-victims and cyber-bully/victims. Insomnia was elevated in the cyber-bully group which is specific to cyberbullying. General aggressiveness and antisocial behavior were more prevalent in cyber-bullies and cyber-bully/victims. Looking at the differences between types of bullying, victims of "school only" and "school and cyber" bullying had higher scores for insomnia and perceived social disintegration than victims of "cyber only" bullying or students "non-involved". Higher general aggressiveness scores were observed for "school only" bullies and "school and cyber" bullies than for bullies in "cyber only" bullying or students "non-involved". Regarding antisocial behavior, "school only" bullies, "cyber only" bullies, "school and cyber" bullies had higher scores than students "non-involved". This study highlights the importance of investigating both school and cyber-bullying as many psychosocial problems are linked to these two specific and highly prevalent forms of bullying. Copyright © 2012 L’Encéphale, Paris. Published by Elsevier Masson SAS. All rights reserved.

  2. Scattering of surface water waves involving semi-infinite floating elastic plates on water of finite depth

    NASA Astrophysics Data System (ADS)

    Chakrabarti, Aloknath; Mohapatra, Smrutiranjan

    2013-09-01

    Two problems of scattering of surface water waves involving a semi-infinite elastic plate and a pair of semi-infinite elastic plates, separated by a gap of finite width, floating horizontally on water of finite depth, are investigated in the present work for a two-dimensional time-harmonic case. Within the frame of linear water wave theory, the solutions of the two boundary value problems under consideration have been represented in the forms of eigenfunction expansions. Approximate values of the reflection and transmission coefficients are obtained by solving an over-determined system of linear algebraic equations in each problem. In both the problems, the method of least squares as well as the singular value decomposition have been employed and tables of numerical values of the reflection and transmission coefficients are presented for specific choices of the parameters for modelling the elastic plates. Our main aim is to check the energy balance relation in each problem which plays a very important role in the present approach of solutions of mixed boundary value problems involving Laplace equations. The main advantage of the present approach of solutions is that the results for the values of reflection and transmission coefficients obtained by using both the methods are found to satisfy the energy-balance relations associated with the respective scattering problems under consideration. The absolute values of the reflection and transmission coefficients are presented graphically against different values of the wave numbers.

  3. Bayesian approach to inverse statistical mechanics.

    PubMed

    Habeck, Michael

    2014-05-01

    Inverse statistical mechanics aims to determine particle interactions from ensemble properties. This article looks at this inverse problem from a Bayesian perspective and discusses several statistical estimators to solve it. In addition, a sequential Monte Carlo algorithm is proposed that draws the interaction parameters from their posterior probability distribution. The posterior probability involves an intractable partition function that is estimated along with the interactions. The method is illustrated for inverse problems of varying complexity, including the estimation of a temperature, the inverse Ising problem, maximum entropy fitting, and the reconstruction of molecular interaction potentials.

  4. Bayesian approach to inverse statistical mechanics

    NASA Astrophysics Data System (ADS)

    Habeck, Michael

    2014-05-01

    Inverse statistical mechanics aims to determine particle interactions from ensemble properties. This article looks at this inverse problem from a Bayesian perspective and discusses several statistical estimators to solve it. In addition, a sequential Monte Carlo algorithm is proposed that draws the interaction parameters from their posterior probability distribution. The posterior probability involves an intractable partition function that is estimated along with the interactions. The method is illustrated for inverse problems of varying complexity, including the estimation of a temperature, the inverse Ising problem, maximum entropy fitting, and the reconstruction of molecular interaction potentials.

  5. Promising lines of research in the realms of laboratory nuclear astrophysics by means of powerful lasers

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

    Belyaev, V. S., E-mail: belyaev@tsniimash.ru; Zagreev, B. V.; Kedrov, A. Yu.

    Basic nuclear-astrophysics problems that can be studied under laboratory conditions at a laserradiation intensity of 10{sup 18} W/cm{sup 2} or more are specified. These are the lithium problem, the problem of determining neutron sources for s-processes of heavy-element formation, the formation of bypassed stable p-nuclei, and nuclear reactions involving isotopes used by astronomers for diagnostics purposes. The results of experiments at the Neodym laser facility are presented, and proposals for further studies in these realms are formulated.

  6. Remote sensing utility in a disaster struck urban environment

    NASA Technical Reports Server (NTRS)

    Rush, M.; Holguin, A.; Vernon, S.

    1974-01-01

    A project to determine the ways in which remote sensing can contribute to solutions of urban public health problems in time of natural disaster is discussed. The objectives of the project are to determine and describe remote sensing standard operating procedures for public health assistance during disaster relief operations which will aid the agencies and organizations involved in disaster intervention. Proposed tests to determine the validity of the remote sensing system are reported.

  7. Control system estimation and design for aerospace vehicles with time delay

    NASA Technical Reports Server (NTRS)

    Allgaier, G. R.; Williams, T. L.

    1972-01-01

    The problems of estimation and control of discrete, linear, time-varying systems are considered. Previous solutions to these problems involved either approximate techniques, open-loop control solutions, or results which required excessive computation. The estimation problem is solved by two different methods, both of which yield the identical algorithm for determining the optimal filter. The partitioned results achieve a substantial reduction in computation time and storage requirements over the expanded solution, however. The results reduce to the Kalman filter when no delays are present in the system. The control problem is also solved by two different methods, both of which yield identical algorithms for determining the optimal control gains. The stochastic control is shown to be identical to the deterministic control, thus extending the separation principle to time delay systems. The results obtained reduce to the familiar optimal control solution when no time delays are present in the system.

  8. REVIEWS OF TOPICAL PROBLEMS: Global phase-stable radiointerferometric systems

    NASA Astrophysics Data System (ADS)

    Dravskikh, A. F.; Korol'kov, Dimitrii V.; Pariĭskiĭ, Yu N.; Stotskiĭ, A. A.; Finkel'steĭn, A. M.; Fridman, P. A.

    1981-12-01

    We discuss from a unitary standpoint the possibility of building a phase-stable interferometric system with very long baselines that operate around the clock with real-time data processing. The various problems involved in the realization of this idea are discussed: the methods of suppression of instrumental and tropospheric phase fluctuations, the methods for constructing two-dimensional images and determining the coordinates of radio sources with high angular resolution, and the problem of the optimal structure of the interferometric system. We review in detail the scientific problems from the various branches of natural science (astrophysics, cosmology, geophysics, geodynamics, astrometry, etc.) whose solution requires superhigh angular resolution.

  9. [Problem-posing as a nutritional education strategy with obese teenagers].

    PubMed

    Rodrigues, Erika Marafon; Boog, Maria Cristina Faber

    2006-05-01

    Obesity is a public health issue with relevant social determinants in its etiology and where interventions with teenagers encounter complex biopsychological conditions. This study evaluated intervention in nutritional education through a problem-posing approach with 22 obese teenagers, treated collectively and individually for eight months. Speech acts were collected through the use of word cards, observer recording, and tape-recording. The study adopted a qualitative methodology, and the approach involved content analysis. Problem-posing facilitated changes in eating behavior, triggering reflections on nutritional practices, family circumstances, social stigma, interaction with health professionals, and religion. Teenagers under individual care posed problems more effectively in relation to eating, while those under collective care posed problems in relation to family and psychological issues, with effective qualitative eating changes in both groups. The intervention helped teenagers understand their life history and determinants of eating behaviors, spontaneously implementing eating changes and making them aware of possibilities for maintaining the new practices and autonomously exercising their role as protagonists in their own health care.

  10. The Boundary Function Method. Fundamentals

    NASA Astrophysics Data System (ADS)

    Kot, V. A.

    2017-03-01

    The boundary function method is proposed for solving applied problems of mathematical physics in the region defined by a partial differential equation of the general form involving constant or variable coefficients with a Dirichlet, Neumann, or Robin boundary condition. In this method, the desired function is defined by a power polynomial, and a boundary function represented in the form of the desired function or its derivative at one of the boundary points is introduced. Different sequences of boundary equations have been set up with the use of differential operators. Systems of linear algebraic equations constructed on the basis of these sequences allow one to determine the coefficients of a power polynomial. Constitutive equations have been derived for initial boundary-value problems of all the main types. With these equations, an initial boundary-value problem is transformed into the Cauchy problem for the boundary function. The determination of the boundary function by its derivative with respect to the time coordinate completes the solution of the problem.

  11. Blind Deconvolution for Distributed Parameter Systems with Unbounded Input and Output and Determining Blood Alcohol Concentration from Transdermal Biosensor Data.

    PubMed

    Rosen, I G; Luczak, Susan E; Weiss, Jordan

    2014-03-15

    We develop a blind deconvolution scheme for input-output systems described by distributed parameter systems with boundary input and output. An abstract functional analytic theory based on results for the linear quadratic control of infinite dimensional systems with unbounded input and output operators is presented. The blind deconvolution problem is then reformulated as a series of constrained linear and nonlinear optimization problems involving infinite dimensional dynamical systems. A finite dimensional approximation and convergence theory is developed. The theory is applied to the problem of estimating blood or breath alcohol concentration (respectively, BAC or BrAC) from biosensor-measured transdermal alcohol concentration (TAC) in the field. A distributed parameter model with boundary input and output is proposed for the transdermal transport of ethanol from the blood through the skin to the sensor. The problem of estimating BAC or BrAC from the TAC data is formulated as a blind deconvolution problem. A scheme to identify distinct drinking episodes in TAC data based on a Hodrick Prescott filter is discussed. Numerical results involving actual patient data are presented.

  12. Planning and Design: A Systems Approach.

    ERIC Educational Resources Information Center

    Bozeman, William C.; Clements, Mary A.

    1981-01-01

    Explains "purpose design," a planning and problem-solving strategy involving determination of planning purposes, generation and selection of solutions, specification of solution details, implementation, and evaluation. Describes the application of purpose design to the planning of an alumni association at Black Hawk College, a community…

  13. Investigation of premature distress in conventional asphalt materials on Interstate 10 at Columbus, Texas.

    DOT National Transportation Integrated Search

    1982-08-01

    The primary objectives of the study were to determine the probable causes of the distress and to make recommendations which could alleviate future problems. The investigation involved an analysis of construction records and laboratory test results pe...

  14. Relief of reinforcing congestion in beams and bent caps of concrete bridges.

    DOT National Transportation Integrated Search

    2012-06-01

    In order to determine how to resolve the issues involving steel congestion in reinforced concrete (RC) structures, three potential solutions to this problem were researched. In the first method, reinforced concrete (RC) was mixed with steel fibers. T...

  15. Running Injuries: The Infrapatellar Fat Pad and Plica Injuries.

    PubMed

    McConnell, Jenny

    2016-02-01

    When considering knee pain in runners, clinicians differentiate sources of symptoms and determine their cause. Knee problems arise when a runner increases the amount/frequency of the loading through the lower limb. The way the loading is distributed through the knee determines which tissues are abnormally loaded. Knee problems cannot be considered in isolation, requiring a thorough investigation of static and dynamic lower limb mechanics, and footwear and surfaces. This article examines potential sources of knee pain and explores the role of the infrapatellar fat pad and synovial plica in the mechanics of the knee and its involvement in knee symptoms. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. Improving teacher perceptions of parent involvement patterns: Findings from a group randomized trial.

    PubMed

    Herman, Keith C; Reinke, Wendy M

    2017-03-01

    For children with the most serious and persistent academic and behavior problems, parent involvement in education, particularly teacher perceptions of involvement, is essential to avert their expected long-term negative outcomes. Despite the widespread interest in and perceived importance of parent involvement in education, however, few experimental studies have evaluated programs and practices to promote it. In this group randomized trial, we examined the effects of the Incredible Years Teacher Classroom Management program (IY TCM) on teacher perceptions of contact and comfort with parents. One hundred five classrooms with 1818 students were randomly assigned to an IY TCM or to a control, business as usual condition. Measures of key constructs included teacher ratings of parent and student behaviors, direct observations in the classroom, and a standardized academic achievement test. Latent transition analysis (LTA) was used to identify patterns of involvement over time and to determine if intervention condition predicted postintervention patterns and transitions. Four patterns of involvement were identified at baseline and at follow-up; parents of students with academic and behavior problems were most likely to be in classes with the least adaptive involvement patterns. Intervention status predicted group membership at follow-up. Specifically, intervention classroom parents were significantly more likely to transition to more adaptive teacher-rated parenting profiles at follow-up compared to control classroom parents. This is the first randomized trial we are aware of that has found that teacher training can alter teacher perceptions of parent involvement patterns. Clinical implications for students with behavior and academic problems are discussed. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  17. Place of the Prosecutor's Office of the Russian Federation in System of Bodies Involved in Criminal Prosecution

    ERIC Educational Resources Information Center

    Grebennikov, Valeriy V.; Sangadzhiev, Badma V.; Vinogradova, Elena V.

    2016-01-01

    The relevance of the study to the problem of determining the place of prosecutors in the system of state bodies carrying out criminal prosecution, is determined, firstly, by the ongoing scientific debates and lack of consensus about the nature of the Prosecutor's office, the place and role of prosecutorial supervision in the structure of the…

  18. Sleep promotes analogical transfer in problem solving.

    PubMed

    Monaghan, Padraic; Sio, Ut Na; Lau, Sum Wai; Woo, Hoi Kei; Linkenauger, Sally A; Ormerod, Thomas C

    2015-10-01

    Analogical problem solving requires using a known solution from one problem to apply to a related problem. Sleep is known to have profound effects on memory and information restructuring, and so we tested whether sleep promoted such analogical transfer, determining whether improvement was due to subjective memory for problems, subjective recognition of similarity across related problems, or by abstract generalisation of structure. In Experiment 1, participants were exposed to a set of source problems. Then, after a 12-h period involving sleep or wake, they attempted target problems structurally related to the source problems but with different surface features. Experiment 2 controlled for time of day effects by testing participants either in the morning or the evening. Sleep improved analogical transfer, but effects were not due to improvements in subjective memory or similarity recognition, but rather effects of structural generalisation across problems. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. A scheme to calculate higher-order homogenization as applied to micro-acoustic boundary value problems

    NASA Astrophysics Data System (ADS)

    Vagh, Hardik A.; Baghai-Wadji, Alireza

    2008-12-01

    Current technological challenges in materials science and high-tech device industry require the solution of boundary value problems (BVPs) involving regions of various scales, e.g. multiple thin layers, fibre-reinforced composites, and nano/micro pores. In most cases straightforward application of standard variational techniques to BVPs of practical relevance necessarily leads to unsatisfactorily ill-conditioned analytical and/or numerical results. To remedy the computational challenges associated with sub-sectional heterogeneities various sophisticated homogenization techniques need to be employed. Homogenization refers to the systematic process of smoothing out the sub-structural heterogeneities, leading to the determination of effective constitutive coefficients. Ordinarily, homogenization involves a sophisticated averaging and asymptotic order analysis to obtain solutions. In the majority of the cases only zero-order terms are constructed due to the complexity of the processes involved. In this paper we propose a constructive scheme for obtaining homogenized solutions involving higher order terms, and thus, guaranteeing higher accuracy and greater robustness of the numerical results. We present

  20. The development of language and literacy: evaluating the stereotypes.

    PubMed

    Goodman, Judith C; Wagovich, Stacy A

    2009-01-01

    People hold many stereotypes about the development of language and reading. We review current data concerning three stereotypes: (1) Girls learn language faster than boys; (2) Biological factors determine the time course of language acquisition; and (3) Dyslexia is a visual problem involving the reversal of letters. In each case, recent data leads to a different picture of the acquisition of language and literacy and deepens our understanding of the processes involved.

  1. A solution to the surface intersection problem. [Boolean functions in geometric modeling

    NASA Technical Reports Server (NTRS)

    Timer, H. G.

    1977-01-01

    An application-independent geometric model within a data base framework should support the use of Boolean operators which allow the user to construct a complex model by appropriately combining a series of simple models. The use of these operators leads to the concept of implicitly and explicitly defined surfaces. With an explicitly defined model, the surface area may be computed by simply summing the surface areas of the bounding surfaces. For an implicitly defined model, the surface area computation must deal with active and inactive regions. Because the surface intersection problem involves four unknowns and its solution is a space curve, the parametric coordinates of each surface must be determined as a function of the arc length. Various subproblems involved in the general intersection problem are discussed, and the mathematical basis for their solution is presented along with a program written in FORTRAN IV for implementation on the IBM 370 TSO system.

  2. Financial Resource Allocation in Higher Education

    ERIC Educational Resources Information Center

    Ušpuriene, Ana; Sakalauskas, Leonidas; Dumskis, Valerijonas

    2017-01-01

    The paper considers a problem of financial resource allocation in a higher education institution. The basic financial management instruments and the multi-stage cost minimization model created are described involving financial instruments to constraints. Both societal and institutional factors that determine the costs of educating students are…

  3. Radiotracer Technology in Mixing Processes for Industrial Applications

    PubMed Central

    Othman, N.; Kamarudin, S. K.

    2014-01-01

    Many problems associated with the mixing process remain unsolved and result in poor mixing performance. The residence time distribution (RTD) and the mixing time are the most important parameters that determine the homogenisation that is achieved in the mixing vessel and are discussed in detail in this paper. In addition, this paper reviews the current problems associated with conventional tracers, mathematical models, and computational fluid dynamics simulations involved in radiotracer experiments and hybrid of radiotracer. PMID:24616642

  4. Brief Intervention for Truant Youth Sexual Risk Behavior and Alcohol Use: A Parallel Process Growth Model Analysis

    PubMed Central

    Dembo, Richard; Briones-Robinson, Rhissa; Ungaro, Rocio; Barrett, Kimberly; Gulledge, Laura; Winters, Ken C.; Belenko, Steven; Karas, Lora M.; Wareham, Jennifer

    2011-01-01

    Truant youths represent a challenging, yet very promising group of at-risk youth to study. In addition to problems in school, they frequently experience troubled family situations, emotional/ psychological problems, involvement in substance use, and delinquency. Given the problems often experienced by truant youth, it is likely they are engaging in alcohol use and sexual risk behavior at a higher rate, than the general youth population. Identification of these youths’ problems and early placement into effective intervention services would benefit them, their families, and society. The current study presents interim findings from an ongoing, NIDA-funded experimental, Brief Intervention (BI) study involving truant youths and their parent/guardians. Baseline, 3-month, 6-month, and 12-month follow up data were analyzed to determine whether alcohol use and sexual risk behaviors were longitudinally related, examine the effects of the intervention on longitudinal alcohol use and sexual risk behaviors, identify latent subgroups of youths in the data for alcohol use and sexual risk behaviors, and determine whether the intervention influenced these subgroups. Results indicated alcohol use and sexual risk were longitudinally related. Subgroups of youth were also identified based on alcohol use and sexual risk behavior levels and trends. Further, limited treatment effects were observed for alcohol use. Implications of the results for future research and service delivery are considered. PMID:25242878

  5. Numerical approximation for the infinite-dimensional discrete-time optimal linear-quadratic regulator problem

    NASA Technical Reports Server (NTRS)

    Gibson, J. S.; Rosen, I. G.

    1986-01-01

    An abstract approximation framework is developed for the finite and infinite time horizon discrete-time linear-quadratic regulator problem for systems whose state dynamics are described by a linear semigroup of operators on an infinite dimensional Hilbert space. The schemes included the framework yield finite dimensional approximations to the linear state feedback gains which determine the optimal control law. Convergence arguments are given. Examples involving hereditary and parabolic systems and the vibration of a flexible beam are considered. Spline-based finite element schemes for these classes of problems, together with numerical results, are presented and discussed.

  6. Program Helps To Determine Chemical-Reaction Mechanisms

    NASA Technical Reports Server (NTRS)

    Bittker, D. A.; Radhakrishnan, K.

    1995-01-01

    General Chemical Kinetics and Sensitivity Analysis (LSENS) computer code developed for use in solving complex, homogeneous, gas-phase, chemical-kinetics problems. Provides for efficient and accurate chemical-kinetics computations and provides for sensitivity analysis for variety of problems, including problems involving honisothermal conditions. Incorporates mathematical models for static system, steady one-dimensional inviscid flow, reaction behind incident shock wave (with boundary-layer correction), and perfectly stirred reactor. Computations of equilibrium properties performed for following assigned states: enthalpy and pressure, temperature and pressure, internal energy and volume, and temperature and volume. Written in FORTRAN 77 with exception of NAMELIST extensions used for input.

  7. Promoting the Involvement of Students with Emotional and Behavioral Disorders in Career and Vocational Planning and Decision-Making: The Self-Determined Career Development Model

    ERIC Educational Resources Information Center

    Benitez, Debra T.; Lattimore, Jennifer; Wehmeyer, Michael L.

    2005-01-01

    The authors examined the effectiveness of a support model to instruct five youth with EBD to self-direct the problem-solving processes and promote self-determination skills by enabling them to: (a) set employment/career related goals, (b) develop and implement a plan toward goal attainment; and (c) adjust and evaluate progress toward meeting their…

  8. Health literacy, numeracy, and other characteristics associated with hospitalized patients' preferences for involvement in decision making.

    PubMed

    Goggins, Kathryn M; Wallston, Kenneth A; Nwosu, Samuel; Schildcrout, Jonathan S; Castel, Liana; Kripalani, Sunil

    2014-01-01

    Little research has examined the association of health literacy and numeracy with patients' preferred involvement in the problem-solving and decision-making process in the hospital. Using a sample of 1,249 patients hospitalized with cardiovascular disease from the Vanderbilt Inpatient Cohort Study (VICS), we assessed patients' preferred level of involvement using responses to two scenarios of differing symptom severity from the Problem-Solving Decision-Making Scale. Using multivariable modeling, we determined the relationship of health literacy, subjective numeracy, and other patient characteristics with preferences for involvement in decisions, and how this differed by scenario. The authors found that patients with higher levels of health literacy desired more participation in the problem-solving and decision-making process, as did patients with higher subjective numeracy skills, greater educational attainment, female gender, less perceived social support, or greater health care system distrust (p<.05 for each predictor in multivariable models). Patients also preferred to participate more in the decision-making process when the hypothetical symptom they were experiencing was less severe (i.e., they deferred more to their physician when the hypothetical symptom was more severe). These findings underscore the role that patient characteristics, especially health literacy and numeracy, play in decisional preferences among hospitalized patients.

  9. Relative Importance of Professional Practice and Engineering Management Competencies

    ERIC Educational Resources Information Center

    Pons, Dirk

    2016-01-01

    Problem: The professional practice of engineering always involves engineering management, but it is difficult to know what specifically to include in the undergraduate curriculum. Approach: The population of New Zealand practising engineers was surveyed to determine the importance they placed on specific professional practice and engineering…

  10. Equal Employment + Equal Pay = Multiple Problems for Colleges and Universities

    ERIC Educational Resources Information Center

    Steinbach, Sheldon Elliot; Reback, Joyce E.

    1974-01-01

    Issues involved in government regulation of university employment practices are discussed: confidentiality of records, pregnancy as a disability, alleged discrimination in benefits, tests and other employment criteria, seniority and layoff, reverse discrimination, use of statistics for determination of discrimination, and the Equal Pay Act. (JT)

  11. Policy-Based Negotiation Engine for Cross-Domain Interoperability

    NASA Technical Reports Server (NTRS)

    Vatan, Farrokh; Chow, Edward T.

    2012-01-01

    A successful policy negotiation scheme for Policy-Based Management (PBM) has been implemented. Policy negotiation is the process of determining the "best" communication policy that all of the parties involved can agree on. Specifically, the problem is how to reconcile the various (and possibly conflicting) communication protocols used by different divisions. The solution must use protocols available to all parties involved, and should attempt to do so in the best way possible. Which protocols are commonly available, and what the definition of "best" is will be dependent on the parties involved and their individual communications priorities.

  12. Finite-element analysis of dynamic fracture

    NASA Technical Reports Server (NTRS)

    Aberson, J. A.; Anderson, J. M.; King, W. W.

    1976-01-01

    Applications of the finite element method to the two dimensional elastodynamics of cracked structures are presented. Stress intensity factors are computed for two problems involving stationary cracks. The first serves as a vehicle for discussing lumped-mass and consistent-mass characterizations of inertia. In the second problem, the behavior of a photoelastic dynamic tear test specimen is determined for the time prior to crack propagation. Some results of a finite element simulation of rapid crack propagation in an infinite body are discussed.

  13. Problem reporting management system performance simulation

    NASA Technical Reports Server (NTRS)

    Vannatta, David S.

    1993-01-01

    This paper proposes the Problem Reporting Management System (PRMS) model as an effective discrete simulation tool that determines the risks involved during the development phase of a Trouble Tracking Reporting Data Base replacement system. The model considers the type of equipment and networks which will be used in the replacement system as well as varying user loads, size of the database, and expected operational availability. The paper discusses the dynamics, stability, and application of the PRMS and addresses suggested concepts to enhance the service performance and enrich them.

  14. The Problem With the Placement Study.

    ERIC Educational Resources Information Center

    Miner, Norris

    This study compared the effectiveness and efficiency of two alternative methods for determining the status of graduates of Seminole Community College. The first method involved the identification of graduates, design and mailing of a questionnaire, and analysis of response data, as mandated by the state. The second method compared computer data…

  15. Projectile Motion without Calculus

    ERIC Educational Resources Information Center

    Rizcallah, Joseph A.

    2018-01-01

    Projectile motion is a constant theme in introductory-physics courses. It is often used to illustrate the application of differential and integral calculus. While most of the problems used for this purpose, such as maximizing the range, are kept at a fairly elementary level, some, such as determining the safe domain, involve not so elementary…

  16. Children's Problems with Focus and Cohesion in Revising.

    ERIC Educational Resources Information Center

    Champagne, Mireille; And Others

    A study was conducted to determine whether children in revising their writing to accommodate new information would make corresponding textual changes to preserve appropriate focus and cohesion. The subjects, 48 children each from grades three, six, and nine, were presented with a task that involved descriptions of pictures with incongruent…

  17. If Anything Can Go Wrong, Maybe It Will.

    ERIC Educational Resources Information Center

    Wager, Jane C.; Rayner, Gail T.

    Thirty personnel involved in various stages of the Training Extension Course (TEC) design, development, and distribution process were interviewed by telephone to determine the major problems perceived within each stage of the program, which provides validated extension training wherever U.S. soldiers are stationed. Those interviewed included TEC…

  18. Speech Motor Development: Integrating Muscles, Movements, and Linguistic Units

    ERIC Educational Resources Information Center

    Smith, Anne

    2006-01-01

    A fundamental problem for those interested in human communication is to determine how ideas and the various units of language structure are communicated through speaking. The physiological concepts involved in the control of muscle contraction and movement are theoretically distant from the processing levels and units postulated to exist in…

  19. A simple language to script and simulate breeding schemes: the breeding scheme language

    USDA-ARS?s Scientific Manuscript database

    It is difficult for plant breeders to determine an optimal breeding strategy given that the problem involves many factors, such as target trait genetic architecture and breeding resource availability. There are many possible breeding schemes for each breeding program. Although simulation study may b...

  20. Perceptions of Violence: A Youthful Perspective

    ERIC Educational Resources Information Center

    Ausbrooks, Angela R.

    2010-01-01

    The purpose of this study was to determine the perceptions of violence among youths, specifically as it relates to problem solving and conflict resolution or retaliation. I conducted a qualitative study with adolescents from fourteen to nineteen years old who completed age- and sex-based scenarios involving a peer conflict. The results indicate…

  1. Proximity alert! Distance related cuneus activation in military veterans with anger and aggression problems.

    PubMed

    Heesink, Lieke; Edward Gladwin, Thomas; Terburg, David; van Honk, Jack; Kleber, Rolf; Geuze, Elbert

    2017-08-30

    Problems involving anger and aggression are common after military deployment, and may involve abnormal responses to threat. This study therefore investigated effects on neural activation related to threat and escapability among veterans with deployment experience. Twenty-seven male veterans with anger and aggression problems (Anger group) and 30 Control veterans performed a virtual predator-task during fMRI measurement. In this task, threat and proximity were manipulated. The distance of cues determined their possibility for escape. Cues signaled impending attack by zooming in towards the participant. If Threat cues, but not Safe cues, reached the participants without being halted by a button press, an aversive noise (105dB scream) was presented. In both the Threat and the Safe condition, closer proximity of the virtual predator resulted in stronger activation in the cuneus in the Anger versus Control group. The results suggest that anger and aggression problems are related to a generalized sensitivity to proximity rather than preparatory processes related to task-contingent aversive stimuli. Anger and aggression problems in natural, dynamically changing environments may be related to an overall heightened vigilance, which is non-adaptively driven by proximity. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

  2. The impact of the participation of settlers to the formation of environment in Kampung Nelayan Belawan Medan

    NASA Astrophysics Data System (ADS)

    Marpaung, B. O. Y.; Waginah

    2018-03-01

    Every existence of community settlements that formed has related to social, culture, and economy that exists in that society. Participation is a process that involving human interaction towards each other, of these interactions creates activities that potentially form a new space (Hendriksen, et al., 2012). Problems in this research are related to community involvement in building residential, determining land used, building roads, and utilities in Kampung Nelayan Belawan Medan residential. The aim of this research is to find the community involvement of building residential, determining land used, building roads, and utilities in Kampung Nelayan Belawan Medan residential. In the process of collecting data, researchers conducted field observation and interviews. Then the researchers connect the theory and interpretation of data in determining the method of data analysis. Then the researchers connect the theory and interpretation of data in determining the method of data analysis. The discovery of this research is that the formation of settlement spaces in the fishing village is inseparable from the participation in Kampung Nelayan Belawan Medan residential.

  3. Mathematical and computational aspects of nonuniform frictional slip modeling

    NASA Astrophysics Data System (ADS)

    Gorbatikh, Larissa

    2004-07-01

    A mechanics-based model of non-uniform frictional sliding is studied from the mathematical/computational analysis point of view. This problem is of a key importance for a number of applications (particularly geomechanical ones), where materials interfaces undergo partial frictional sliding under compression and shear. We show that the problem is reduced to Dirichlet's problem for monotonic loading and to Riemman's problem for cyclic loading. The problem may look like a traditional crack interaction problem, however, it is confounded by the fact that locations of n sliding intervals are not known. They are to be determined from the condition for the stress intensity factors: KII=0 at the ends of the sliding zones. Computationally, it reduces to solving a system of 2n coupled non-linear algebraic equations involving singular integrals with unknown limits of integration.

  4. A personality-based description of maturing out of alcohol problems: extension with a five-factor model and robustness to modeling challenges.

    PubMed

    Littlefield, Andrew K; Sher, Kenneth J; Wood, Phillip K

    2010-11-01

    To examine the relation of changes in Five-Factor personality traits (i.e., extraversion, agreeableness, conscientiousness, neuroticism, and openness to experience; Costa & McCrae, 1985), drinking motives, and problematic alcohol involvement in a cohort of college students (N=467) at varying risk for alcohol use disorders from ages 21 to 35. Parallel process latent growth models were estimated to determine the extent that prospective changes in personality and alcohol problems covaried as well as the extent to which drinking motives appeared to mediate these relations. Changes in neuroticism and conscientiousness covaried with changes in problematic alcohol involvement. Specifically, increases in conscientiousness and decreases in neuroticism were related to decreases in alcohol from ages 21 to 35, even after accounting for marriage and/or parenthood. Change in coping (but not enhancement) motives specifically mediated the relation between changes in conscientiousness and alcohol problems in addition to the relation between changes in neuroticism and alcohol problems. Personality changes, as assessed by a Five-Factor model of personality, are associated with "maturing out" of alcohol problems. Of equal importance, change in coping motives may be an important mediator of the relation between personality change and the "maturing out" of alcohol problems. Published by Elsevier Ltd.

  5. Two-phase flows in the formed tornado funnel

    NASA Astrophysics Data System (ADS)

    Sinkevich, O. A.; Bortsova, A. A.

    2017-10-01

    At present, it is obvious that the problem of the tornado is important not only for our planetЮ to determine the conditions for the formation of a tornado, it is required to take into account a number of hydrodynamic and plasma processes [1 - 6]. Along to prediction of a tornado generation conditions [1 - 3] it is necessary to evaluate the characteristics of its quasi-stationary motion in a formed funnel: the mass of the moving moist air involved in the funnel and the size and form of the funnel. For a complete description of the phenomena, it is necessary to involve numerical calculations. We note that even for numerical calculations using powerful computers, the problem is very difficult because of the need to calculate multiphase turbulent flows with free, self-organizing boundaries [1, 6]. However, “strict” numerical calculations, it is impossible to do without the use of many, often mutually exclusive, models. For example, how to choice an adequate model of turbulence (algebraic, k-ε model, etc.) or the use of additional, often not accepted, hypotheses about certain processes used in calculations (mechanisms on the nature of moisture condensation, etc.). Therefore, along with numerical calculations of such flows, modeling problems that allow an exact solution and allow to determine the most important and observed characteristics of a tornado.

  6. A mixed-mode crack analysis of isotropic solids using conservation laws of elasticity

    NASA Technical Reports Server (NTRS)

    Yau, J. F.; Wang, S. S.; Corten, H. T.

    1980-01-01

    A simple and convenient method of analysis for studying two-dimensional mixed-mode crack problems is presented. The analysis is formulated on the basis of conservation laws of elasticity and of fundamental relationships in fracture mechanics. The problem is reduced to the determination of mixed-mode stress-intensity factor solutions in terms of conservation integrals involving known auxiliary solutions. One of the salient features of the present analysis is that the stress-intensity solutions can be determined directly by using information extracted in the far field. Several examples with solutions available in the literature are solved to examine the accuracy and other characteristics of the current approach. This method is demonstrated to be superior in its numerical simplicity and computational efficiency to other approaches. Solutions of more complicated and practical engineering fracture problems dealing with the crack emanating from a circular hole are presented also to illustrate the capacity of this method

  7. A study of the relationship between the study process, motivation resources, and motivation problems of nursing students in different educational systems.

    PubMed

    Yardimci, Figen; Bektaş, Murat; Özkütük, Nilay; Muslu, Gonca Karayağız; Gerçeker, Gülçin Özalp; Başbakkal, Zümrüt

    2017-01-01

    The study process is related to students' learning approaches and styles. Motivation resources and problems determine students' internal, external, and negative motivation. Analyzing the study process and motivation of students yields important indications about the nature of educational systems in higher education. This study aims to analyze the relationship between the study process, and motivation resources and problems with regard to nursing students in different educational systems in Turkey and to reveal their effects according to a set of variables. This is a descriptive, cross-sectional and correlational study. Traditional, integrated and problem-based learning (PBL) educational programs for nurses involving students from three nursing schools in Turkey. Nursing students (n=330). The data were collected using the Study Process Questionnaire (R-SPQ-2F) and the Motivation Resources and Problems (MRP) Scale. A statistically significant difference was found between the scores on the study process scale, and motivation resources and problems scale among the educational systems. This study determined that the mean scores of students in the PBL system on learning approaches, intrinsic motivation and negative motivation were higher. A positive significant correlation was found between the scales. The study process, and motivation resources and problems were found to be affected by the educational system. This study determined that the PBL educational system more effectively increases students' intrinsic motivation and helps them to acquire learning skills. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Towards a Methodology for Identifying Program Constraints During Requirements Analysis

    NASA Technical Reports Server (NTRS)

    Romo, Lilly; Gates, Ann Q.; Della-Piana, Connie Kubo

    1997-01-01

    Requirements analysis is the activity that involves determining the needs of the customer, identifying the services that the software system should provide and understanding the constraints on the solution. The result of this activity is a natural language document, typically referred to as the requirements definition document. Some of the problems that exist in defining requirements in large scale software projects includes synthesizing knowledge from various domain experts and communicating this information across multiple levels of personnel. One approach that addresses part of this problem is called context monitoring and involves identifying the properties of and relationships between objects that the system will manipulate. This paper examines several software development methodologies, discusses the support that each provide for eliciting such information from experts and specifying the information, and suggests refinements to these methodologies.

  9. Transport of reacting solutes in porous media: Relation between mathematical nature of problem formulation and chemical nature of reactions

    USGS Publications Warehouse

    Rubin, Jacob

    1983-01-01

    Examples involving six broad reaction classes show that the nature of transport-affecting chemistry may have a profound effect on the mathematical character of solute transport problem formulation. Substantive mathematical diversity among such formulations is brought about principally by reaction properties that determine whether (1) the reaction can be regarded as being controlled by local chemical equilibria or whether it must be considered as being controlled by kinetics, (2) the reaction is homogeneous or heterogeneous, (3) the reaction is a surface reaction (adsorption, ion exchange) or one of the reactions of classical chemistry (e.g., precipitation, dissolution, oxidation, reduction, complex formation). These properties, as well as the choice of means to describe them, stipulate, for instance, (1) the type of chemical entities for which a formulation's basic, mass-balance equations should be written; (2) the nature of mathematical transformations needed to change the problem's basic equations into operational ones. These and other influences determine such mathematical features of problem formulations as the nature of the operational transport-equation system (e.g., whether it involves algebraic, partial-differential, or integro-partial-differential simultaneous equations), the type of nonlinearities of such a system, and the character of the boundaries (e.g., whether they are stationary or moving). Exploration of the reasons for the dependence of transport mathematics on transport chemistry suggests that many results of this dependence stem from the basic properties of the reactions' chemical-relation (i.e., equilibrium or rate) equations.

  10. Split Orthogonal Group: A Guiding Principle for Sign-Problem-Free Fermionic Simulations

    NASA Astrophysics Data System (ADS)

    Wang, Lei; Liu, Ye-Hua; Iazzi, Mauro; Troyer, Matthias; Harcos, Gergely

    2015-12-01

    We present a guiding principle for designing fermionic Hamiltonians and quantum Monte Carlo (QMC) methods that are free from the infamous sign problem by exploiting the Lie groups and Lie algebras that appear naturally in the Monte Carlo weight of fermionic QMC simulations. Specifically, rigorous mathematical constraints on the determinants involving matrices that lie in the split orthogonal group provide a guideline for sign-free simulations of fermionic models on bipartite lattices. This guiding principle not only unifies the recent solutions of the sign problem based on the continuous-time quantum Monte Carlo methods and the Majorana representation, but also suggests new efficient algorithms to simulate physical systems that were previously prohibitive because of the sign problem.

  11. Traditional bullying and cyberbullying: Differences in emotional problems, and personality. Are cyberbullies more Machiavellians?

    PubMed

    Resett, Santiago; Gamez-Guadix, Manuel

    2017-12-01

    Few studies have examined differences in emotional problems and personality of traditional bullies and cyberbullies. The present study aimed to determine whether those engaged in cyberbullying differ in emotional problems, and personality from those engage in traditional bullying perpetration. An Argentinean sample of 898 high school students was recruited (56% female; mean age = 15.2 SD = 1.6). Adolescents completed measures of traditional bullying, cyberbullying, self-esteem, anxiety, depression, and personality. A 6% were traditional bullies; 8%, cyberbullies; and 4% were involved in both forms; the remainders were non involved. Results indicated that cyberbullies showed less depression and anxiety than traditional bullies. Also, cyberbullies scored low in neuroticism and high in agreeableness compared to traditional bullies. The results suggest that cyberbullies are characterized by an emotional and personality profile different from traditional bullies. In the discussion we analyze the implications of these results. Copyright © 2017 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

  12. Comparative Effectiveness of Context-Based and Traditional Approaches in Teaching Genetics: Student Views and Achievement

    ERIC Educational Resources Information Center

    Kazeni, Monde; Onwu, Gilbert

    2013-01-01

    The study aimed to determine the comparative effectiveness of context-based and traditional teaching approaches in enhancing student achievement in genetics, problem-solving, science inquiry and decision-making skills, and attitude towards the study of life sciences. A mixed method but essentially quantitative research approach involving a…

  13. Faculty Salary Equity: Issues and Options. AIR 1993 Annual Forum Paper.

    ERIC Educational Resources Information Center

    Snyder, Julie K.; And Others

    This paper presents a multi-phased approach to identifying and correcting gender-based salary inequities within institutions of higher education. The major steps in this approach involve: (1) determining if a problem situation exists by using a conceptually sound, objective procedure that does a legal and effective job of explaining faculty…

  14. Motor Deficits Following Pediatric Mild Traumatic Brain Injury: Implications for School Psychologists

    ERIC Educational Resources Information Center

    Davis, Andrew S.; Moore, Brittney; Rice, Valerie; Decker, Scott

    2015-01-01

    Mild traumatic brain injury (mTBI), sometimes referred to as concussion, is one of the most common acquired neurological problems of childhood. When children return to school following mTBI, school psychologists should be actively involved in the determination of neurocognitive and functional deficits for the purpose of designing strength-based…

  15. Pathways from Polyvictimization to Youth Problem Behaviors: The Critical Role of School Engagement

    ERIC Educational Resources Information Center

    Voisin, Dexter R.; Elsaesser, Caitlin M.

    2013-01-01

    School engagement has a powerful influence on youth development. Youth who fail in school are at significant risk for a host of subsequent psychosocial outcomes, including substance use, risky sexual behaviors, gang involvement, and increased contact with juvenile justice authorities. Although school engagement is an important determinant of key…

  16. Law Enforcement Officer Training, Basic Course. Learner's Manual.

    ERIC Educational Resources Information Center

    Ohio State Dept. of Education, Columbus. Trade and Industrial Education Service.

    Developed by the State Division of Vocational Education, this learner's manual is designed to provide law enforcement officers with a better understanding of the many problems involved in providing good law enforcement services. The objectives of this program are to determine local, county, regional and state needs, to implement a program to meet…

  17. Implementation of Biofeedback Techniques To Reduce Stress Involving Communication Skills with Elementary School Hearing Impaired Students.

    ERIC Educational Resources Information Center

    Litus, Tonyia J.

    Two sixth-grade, hearing-impaired students were studied to determine the effectiveness of stress management techniques using biofeedback instruments to monitor their nervous and cardiovascular systems. The male student had behavior problems, exhibiting explosive behavior without warning. The female student experienced excessive audible inhalations…

  18. TEACHING SPELLING. WHAT RESEARCH SAYS TO THE TEACHER, NUMBER 3.

    ERIC Educational Resources Information Center

    HORN, ERNEST

    SPELLING ABILITY IS IMPORTANT EVEN THOUGH SPELLING MAY BE A MINOR SUBJECT IN THE CURRICULUM. THE CHIEF PROBLEMS INVOLVED IN DESIGNING THE SPELLING CURRICULUM ARE DETERMINATION OF OBJECTIVES, SELECTION OF CONTENT, AND ORGANIZATION AND ARRANGEMENT OF CONTENT BY GRADES. SPELLING INSTRUCTION SHOULD CONSUME NOT MORE THAN 75 MINUTES PER WEEK AND SHOULD…

  19. Outcomes of Adventure Program Participation by Adolescents Involved in Psychiatric Treatment.

    ERIC Educational Resources Information Center

    Witman, Jeffrey P.

    The purpose of this study was to determine the impact of adventure program participation upon adolescents in psychiatric treatment. All adventure programs included goal setting, awareness, cooperative and trust activities, and group and individual problem-solving. Participants' total hours of program participation ranged from 8-22 hours. A random…

  20. Effects of risk attitudes on extended attack fire management decisionmaking

    Treesearch

    Donald G. MacGregor; Armando González-Cabán

    2009-01-01

    Fire management inherently involves the assessment and management of risk, and decision making under uncertainty. Although organizational standards and guides are an important determinant of how decision problems are structured and framed, decision makers may view risk-based decisions from a perspective that is unique to their background and experience. Previous...

  1. Reformulation of the covering and quantizer problems as ground states of interacting particles.

    PubMed

    Torquato, S

    2010-11-01

    It is known that the sphere-packing problem and the number-variance problem (closely related to an optimization problem in number theory) can be posed as energy minimizations associated with an infinite number of point particles in d-dimensional Euclidean space R(d) interacting via certain repulsive pair potentials. We reformulate the covering and quantizer problems as the determination of the ground states of interacting particles in R(d) that generally involve single-body, two-body, three-body, and higher-body interactions. This is done by linking the covering and quantizer problems to certain optimization problems involving the "void" nearest-neighbor functions that arise in the theory of random media and statistical mechanics. These reformulations, which again exemplify the deep interplay between geometry and physics, allow one now to employ theoretical and numerical optimization techniques to analyze and solve these energy minimization problems. The covering and quantizer problems have relevance in numerous applications, including wireless communication network layouts, the search of high-dimensional data parameter spaces, stereotactic radiation therapy, data compression, digital communications, meshing of space for numerical analysis, and coding and cryptography, among other examples. In the first three space dimensions, the best known solutions of the sphere-packing and number-variance problems (or their "dual" solutions) are directly related to those of the covering and quantizer problems, but such relationships may or may not exist for d≥4 , depending on the peculiarities of the dimensions involved. Our reformulation sheds light on the reasons for these similarities and differences. We also show that disordered saturated sphere packings provide relatively thin (economical) coverings and may yield thinner coverings than the best known lattice coverings in sufficiently large dimensions. In the case of the quantizer problem, we derive improved upper bounds on the quantizer error using sphere-packing solutions, which are generally substantially sharper than an existing upper bound in low to moderately large dimensions. We also demonstrate that disordered saturated sphere packings yield relatively good quantizers. Finally, we remark on possible applications of our results for the detection of gravitational waves.

  2. Reformulation of the covering and quantizer problems as ground states of interacting particles

    NASA Astrophysics Data System (ADS)

    Torquato, S.

    2010-11-01

    It is known that the sphere-packing problem and the number-variance problem (closely related to an optimization problem in number theory) can be posed as energy minimizations associated with an infinite number of point particles in d -dimensional Euclidean space Rd interacting via certain repulsive pair potentials. We reformulate the covering and quantizer problems as the determination of the ground states of interacting particles in Rd that generally involve single-body, two-body, three-body, and higher-body interactions. This is done by linking the covering and quantizer problems to certain optimization problems involving the “void” nearest-neighbor functions that arise in the theory of random media and statistical mechanics. These reformulations, which again exemplify the deep interplay between geometry and physics, allow one now to employ theoretical and numerical optimization techniques to analyze and solve these energy minimization problems. The covering and quantizer problems have relevance in numerous applications, including wireless communication network layouts, the search of high-dimensional data parameter spaces, stereotactic radiation therapy, data compression, digital communications, meshing of space for numerical analysis, and coding and cryptography, among other examples. In the first three space dimensions, the best known solutions of the sphere-packing and number-variance problems (or their “dual” solutions) are directly related to those of the covering and quantizer problems, but such relationships may or may not exist for d≥4 , depending on the peculiarities of the dimensions involved. Our reformulation sheds light on the reasons for these similarities and differences. We also show that disordered saturated sphere packings provide relatively thin (economical) coverings and may yield thinner coverings than the best known lattice coverings in sufficiently large dimensions. In the case of the quantizer problem, we derive improved upper bounds on the quantizer error using sphere-packing solutions, which are generally substantially sharper than an existing upper bound in low to moderately large dimensions. We also demonstrate that disordered saturated sphere packings yield relatively good quantizers. Finally, we remark on possible applications of our results for the detection of gravitational waves.

  3. Unsteady Subsonic and Transonic Potential Flow over Helicopter Rotor Blades

    NASA Technical Reports Server (NTRS)

    Isom, M. P.

    1974-01-01

    Differential equations and boundary conditions for a rotor blade in forward flight, with subsonic or transonic tip Mach number, are derived. A variety of limiting flow regimes determined by different limits involving blade thickness ratio, aspect ratio, advance ratio and maximum tip Mach number is discussed. The transonic problem is discussed in some detail, and in particular the conditions that make this problem quasi-steady or essentially unsteady are determined. Asymptotic forms of equations and boundary conditions that are valid in an appropriately scaled region of the tip and an azimuthal sector on the advancing side are derived. The equations are then put in a form that is valid from the blade tip inboard through the strip theory region.

  4. Health practices, problems, and needs in a population of Micronesian adolescents.

    PubMed

    Mayer, P A; Bauman, K A

    1986-09-01

    Saipan, one of many islands of the Pacific Trust Territory, depends on the United States for its medical care. The limited resources on the island have resulted in little medical attention for adolescents. This study surveyed 519 Saipan adolescents to determine their health practices, problems, and needs. Although these teenagers rarely saw physicians, they commonly reported health problems such as headaches, abdominal pain, and dental cavities. In the psychosocial arena, their problems involved parents, girlfriends/boyfriends, school, and suicidal thoughts. The health topics found to be of most interest included sex education, jobs, suicide prevention, drugs, and birth control. The most popular methods for learning about these subjects were books, movies, films, and school classes. There were high reported incidences of drug and alcohol problems among boys, and thoughts about suicide in all respondents.

  5. Sociocultural Determinants of Risky Sexual Behaviors among Adult Latinas: A Longitudinal Study of a Community-Based Sample.

    PubMed

    Rojas, Patria; Huang, Hui; Li, Tan; Ravelo, Gira J; Sanchez, Mariana; Dawson, Christyl; Brook, Judith; Kanamori, Mariano; De La Rosa, Mario

    2016-11-23

    Few studies have examined the sociocultural determinants of risky sexual behavior trajectories among adult Latinas. To longitudinally examine the link between sociocultural determinants of risky sexual behaviors, we followed a sample of adult Latina mother-daughter dyads ( n = 267) across a 10-year span through four waves of data collection. The present study investigates how risky sexual behavior (operationalized as sex under the influence of alcohol or other drugs, sex without a condom, or multiple sex partners) is affected by: (a) socioeconomic conditions; (b) mental health; (c) medical health; (d) acculturation to U.S. culture; (e) interpersonal support; (f) relationship stress; (g) mother-daughter attachment; (h) intimate partner violence; (i) religious involvement; and (j) criminal justice involvement. Results indicate the following factors are negatively associated with risky sexual behavior: drug and alcohol use, treating a physical problem with prescription drugs, religious involvement, and mother-daughter attachment. The following factors are positively associated with risky sexual behavior: higher number of mental health symptoms, being U.S.-born, and criminal justice involvement. We discuss implications for the future development of culturally relevant interventions based on the study findings.

  6. Sociocultural Determinants of Risky Sexual Behaviors among Adult Latinas: A Longitudinal Study of a Community-Based Sample

    PubMed Central

    Rojas, Patria; Huang, Hui; Li, Tan; Ravelo, Gira J.; Sanchez, Mariana; Dawson, Christyl; Brook, Judith; Kanamori, Mariano; De La Rosa, Mario

    2016-01-01

    Few studies have examined the sociocultural determinants of risky sexual behavior trajectories among adult Latinas. To longitudinally examine the link between sociocultural determinants of risky sexual behaviors, we followed a sample of adult Latina mother-daughter dyads (n = 267) across a 10-year span through four waves of data collection. The present study investigates how risky sexual behavior (operationalized as sex under the influence of alcohol or other drugs, sex without a condom, or multiple sex partners) is affected by: (a) socioeconomic conditions; (b) mental health; (c) medical health; (d) acculturation to U.S. culture; (e) interpersonal support; (f) relationship stress; (g) mother-daughter attachment; (h) intimate partner violence; (i) religious involvement; and (j) criminal justice involvement. Results indicate the following factors are negatively associated with risky sexual behavior: drug and alcohol use, treating a physical problem with prescription drugs, religious involvement, and mother–daughter attachment. The following factors are positively associated with risky sexual behavior: higher number of mental health symptoms, being U.S.-born, and criminal justice involvement. We discuss implications for the future development of culturally relevant interventions based on the study findings. PMID:27886095

  7. Child Involvement in Interparental Conflict and Child Adjustment Problems: A Longitudinal Study of Violent Families

    PubMed Central

    Jouriles, Ernest N.; Rosenfield, David; McDonald, Renee; Mueller, Victoria

    2014-01-01

    This study examined whether child involvement in interparental conflict predicts child externalizing and internalizing problems in violent families. Participants were 119 families (mothers and children) recruited from domestic violence shelters. One child between the ages of 7 and 10 years in each family (50 female, 69 male) completed measures of involvement in their parents’ conflicts, externalizing problems, and internalizing problems. Mothers completed measures of child externalizing and internalizing problems, and physical intimate partner violence. Measures were completed at three assessments, spaced 6 months apart. Results indicated that children’s involvement in their parents’ conflicts was positively associated with child adjustment problems. These associations emerged in between-subjects and within-subjects analyses, and for child externalizing as well as internalizing problems, even after controlling for the influence of physical intimate partner violence. In addition, child involvement in parental conflicts predicted later child reports of externalizing problems, but child reports of externalizing problems did not predict later involvement in parental conflicts. These findings highlight the importance of considering children’s involvement in their parents’ conflicts in theory and clinical work pertaining to high-conflict families. PMID:24249486

  8. Lower Sensitivity to Happy and Angry Facial Emotions in Young Adults with Psychiatric Problems

    PubMed Central

    Vrijen, Charlotte; Hartman, Catharina A.; Lodder, Gerine M. A.; Verhagen, Maaike; de Jonge, Peter; Oldehinkel, Albertine J.

    2016-01-01

    Many psychiatric problem domains have been associated with emotion-specific biases or general deficiencies in facial emotion identification. However, both within and between psychiatric problem domains, large variability exists in the types of emotion identification problems that were reported. Moreover, since the domain-specificity of the findings was often not addressed, it remains unclear whether patterns found for specific problem domains can be better explained by co-occurrence of other psychiatric problems or by more generic characteristics of psychopathology, for example, problem severity. In this study, we aimed to investigate associations between emotion identification biases and five psychiatric problem domains, and to determine the domain-specificity of these biases. Data were collected as part of the ‘No Fun No Glory’ study and involved 2,577 young adults. The study participants completed a dynamic facial emotion identification task involving happy, sad, angry, and fearful faces, and filled in the Adult Self-Report Questionnaire, of which we used the scales depressive problems, anxiety problems, avoidance problems, Attention-Deficit Hyperactivity Disorder (ADHD) problems and antisocial problems. Our results suggest that participants with antisocial problems were significantly less sensitive to happy facial emotions, participants with ADHD problems were less sensitive to angry emotions, and participants with avoidance problems were less sensitive to both angry and happy emotions. These effects could not be fully explained by co-occurring psychiatric problems. Whereas this seems to indicate domain-specificity, inspection of the overall pattern of effect sizes regardless of statistical significance reveals generic patterns as well, in that for all psychiatric problem domains the effect sizes for happy and angry emotions were larger than the effect sizes for sad and fearful emotions. As happy and angry emotions are strongly associated with approach and avoidance mechanisms in social interaction, these mechanisms may hold the key to understanding the associations between facial emotion identification and a wide range of psychiatric problems. PMID:27920735

  9. Problem-Framing: A perspective on environmental problem-solving

    NASA Astrophysics Data System (ADS)

    Bardwell, Lisa V.

    1991-09-01

    The specter of environmental calamity calls for the best efforts of an involved public. Ironically, the way people understand the issues all too often serves to discourage and frustrate rather than motivate them to action. This article draws from problem-solving perspectives offered by cognitive psychology and conflict management to examine a framework for thinking about environmental problems that promises to help rather than hinder efforts to address them. Problem-framing emphasizes focusing on the problem definition. Since how one defines a problem determines one's understanding of and approach to that problem, being able to redefine or reframe a problem and to explore the “problem space” can help broaden the range of alternatives and solutions examined. Problem-framing incorporates a cognitive perspective on how people respond to information. It explains why an emphasis on problem definition is not part of people's typical approach to problems. It recognizes the importance of structure and of having ways to organize that information on one's problem-solving effort. Finally, problem-framing draws on both cognitive psychology and conflict management for strategies to manage information and to create a problem-solving environment that not only encourages participation but can yield better approaches to our environmental problems.

  10. The Relationship Between Father Involvement and Child Problem Behaviour in Intact Families: A 7-Year Cross-Lagged Study.

    PubMed

    Flouri, Eirini; Midouhas, Emily; Narayanan, Martina K

    2016-07-01

    This study investigated the cross-lagged relationship between father involvement and child problem behaviour across early-to-middle childhood, and tested whether temperament modulated any cross-lagged child behaviour effects on father involvement. It used data from the first four waves of the UK's Millennium Cohort Study, when children (50.3 % male) were aged 9 months, and 3, 5 and 7 years. The sample was 8302 families where both biological parents were co-resident across the four waves. Father involvement (participation in play and physical and educational activities with the child) was measured at ages 3, 5 and 7, as was child problem behaviour (assessed with the Strengths and Difficulties Questionnaire). Key child and family covariates related to father involvement and child problem behaviour were controlled. Little evidence was found that more father involvement predicted less child problem behaviour two years later, with the exception of father involvement at child's age 5 having a significant, but small, effect on peer problems at age 7. There were two child effects. More hyperactive children at age 3 had more involved fathers at age 5, and children with more conduct problems at age 3 had more involved fathers at age 5. Child temperament did not moderate any child behaviour effects on father involvement. Thus, in young, intact UK families, child adjustment appears to predict, rather than be predicted by, father involvement in early childhood. When children showed more problematic behaviours, fathers did not become less involved. In fact, early hyperactivity and conduct problems in children seemed to elicit more involvement from fathers. At school age, father involvement appeared to affect children's social adjustment rather than vice versa.

  11. A new method for determining acoustic-liner admittance in a rectangular duct with grazing flow from experimental data

    NASA Technical Reports Server (NTRS)

    Watson, W. R.

    1984-01-01

    A method is developed for determining acoustic liner admittance in a rectangular duct with grazing flow. The axial propagation constant, cross mode order, and mean flow profile is measured. These measured data are then input into an analytical program which determines the unknown admittance value. The analytical program is based upon a finite element discretization of the acoustic field and a reposing of the unknown admittance value as a linear eigenvalue problem on the admittance value. Gaussian elimination is employed to solve this eigenvalue problem. The method used is extendable to grazing flows with boundary layers in both transverse directions of an impedance tube (or duct). Predicted admittance values are compared both with exact values that can be obtained for uniform mean flow profiles and with those from a Runge Kutta integration technique for cases involving a one dimensional boundary layer.

  12. Interstellar problems and matrix solutions

    NASA Technical Reports Server (NTRS)

    Allamandola, Louis J.

    1987-01-01

    The application of the matrix isolation technique to interstellar problems is described. Following a brief discussion of the interstellar medium (ISM), three areas are reviewed in which matrix experiments are particularly well suited to contribute the information which is sorely needed to further understanding of the ISM. The first involves the measurement of the spectroscopic properties of reactive species. The second is the determination of reaction rates and the elucidation of reaction pathways involving atoms, radicals, and ions which are likely to interact on grain surfaces and in grain mantles. The third entails the determiantion of the spectroscopic, photochemical, and photophysical properties of interstellar and cometary ice analogs. Significant, but limited, progress has been made in these three areas, and a tremendous amount of work is required to fully address the variety of unique chemical and spectroscopic questions posed by the astronomical observations.

  13. Analysis of the flow field generated near an aircraft engine operating in reverse thrust. M.S. Thesis

    NASA Technical Reports Server (NTRS)

    Ledwith, W. A., Jr.

    1972-01-01

    A computer solution is developed to the exhaust gas reingestion problem for aircraft operating in the reverse thrust mode on a crosswind-free runway. The computer program determines the location of the inlet flow pattern, whether the exhaust efflux lies within the inlet flow pattern or not, and if so, the approximate time before the reversed flow reaches the engine inlet. The program is written so that the user is free to select discrete runway speeds or to study the entire aircraft deceleration process for both the far field and cross-ingestion problems. While developed with STOL applications in mind, the solution is equally applicable to conventional designs. The inlet and reversed jet flow fields involved in the problem are assumed to be noninteracting. The nacelle model used in determining the inlet flow field is generated using an iterative solution to the Neuman problem from potential flow theory while the reversed jet flow field is adapted using an empirical correlation from the literature. Sample results obtained using the program are included.

  14. Detecting math problem solving strategies: an investigation into the use of retrospective self-reports, latency and fMRI data.

    PubMed

    Tenison, Caitlin; Fincham, Jon M; Anderson, John R

    2014-02-01

    This research explores how to determine when mathematical problems are solved by retrieval versus computation strategies. Past research has indicated that verbal reports, solution latencies, and neural imaging all provide imperfect indicators of this distinction. Participants in the current study solved mathematical problems involving two distinct problem types, called 'Pyramid' and 'Formula' problems. Participants were given extensive training solving 3 select Pyramid and 3 select Formula problems. Trained problems were highly practiced, whereas untrained problems were not. The distinction between untrained and trained problems was observed in the data. Untrained problems took longer to solve, more often used procedural strategies and showed a greater activation in the horizontal intraparietal sulcus (HIPS) when compared to trained problems. A classifier fit to the neural distinction between trained-untrained problems successfully predicted training within and between the two problem types. We employed this classifier to generate a prediction of strategy use. By combining evidence from the classifier, problem solving latencies, and retrospective reports, we predicted the strategy used to solve each problem in the scanner and gained unexpected insight into the distinction between different strategies. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. Effects Of Rapid Crushing On Composites

    NASA Technical Reports Server (NTRS)

    Farley, Gary L.

    1990-01-01

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

  16. Communication Barriers: A Study of Eastern Mediterranean University Students' and Teachers' of Online Program and Courses

    ERIC Educational Resources Information Center

    Isman, Aytekin; Altinay, Fahriye

    2005-01-01

    This research study defines communication barriers in online programs and courses by determining the perceptions of students and teachers at Eastern Mediterranean University. It aims to get the answers to the questions of what sorts of problems students and teachers face while being involved in online courses and online programs. Distance…

  17. Post Viking planetary protection requirements study

    NASA Technical Reports Server (NTRS)

    Wolfson, R. P.

    1977-01-01

    Past planetary quarantine requirements were reviewed in the light of present Viking data to determine the steps necessary to prevent contamination of the Martian surface on future missions. The currently used term planetary protection reflects a broader scope of understanding of the problems involved. Various methods of preventing contamination are discussed in relation to proposed projects, specifically the 1984 Rover Mission.

  18. The Potential Transfer of Industrial Skills from Defense to Nondefense Industries. Volume 1.

    ERIC Educational Resources Information Center

    California State Dept. of Employment, Sacramento.

    Because of lack of knowledge of specific occupations in defense production, assessment of the impact of defense cutbacks on the economy has been difficult. This project was undertaken to determine which skills of industrial workers in missile production are transferable to nondefense industries and to anticipate manpower problems involved in mass…

  19. Neither Feast nor Famine: Summary of the Second Twenty Year Forecast Project.

    ERIC Educational Resources Information Center

    Enzer, Selwyn; And Others

    1977-01-01

    The key question to ask in determining whether a solution will be found to the world food problem is whether people will learn to effectively manage the food/population balance. Predictions concerning the world food situation should be made on the basis of these factors: (1) possible future changes involving technological development, political…

  20. Sex and Locus of Control as Determinants of Children's Responses to Peer versus Adult Praise.

    ERIC Educational Resources Information Center

    Henry, Susan E.; And Others

    1979-01-01

    Black first graders varying in internal-external control completed digit substitution problems during which performance was praised by a Black boy and girl or a Black man and woman. Boys were most responsive to peer feedback and girls to adult feedback. Predictions involving locus of control were modestly supported. (Author/RD)

  1. Effects of Training Auditory Sequential Memory and Attention on Reading.

    ERIC Educational Resources Information Center

    Klein, Pnina S.; Schwartz, Allen A.

    To determine if auditory sequential memory (ASM) in young children can be improved through training and to discover the effects of such training on the reading scores of children with reading problems, a study was conducted involving 92 second and third graders. For purposes of this study, auditory sequential memory was defined as the ability to…

  2. Retention: An Inductive Study of Representative Student Groups at Middlesex County College.

    ERIC Educational Resources Information Center

    Harrower, Gordon, Jr.; And Others

    This five-part report describes a study conducted by Middlesex County College (MCC) to examine the problems and experiences of various segments of its student body and to determine, on the basis of this examination, factors that aggravate student/college interaction and increase student attrition. Part I details study procedures, which involved a…

  3. Program Evaluation of a Special Education Day School for Conduct Problem Adolescents.

    ERIC Educational Resources Information Center

    Maher, Charles A.

    1981-01-01

    Describes a procedure for program evaluation of a special education day school. The procedure enables a program evaluator to: (1) identify priority evaluation information needs of a school staff, (2) involve those persons in evaluation design and implementation, and (3) determine the utility of the evaluation for program decision-making purposes.…

  4. Gait as solution, but what is the problem? Exploring cost, economy and compromise in locomotion.

    PubMed

    Bertram, John E A

    2013-12-01

    Many studies have examined how legged mammals move, defining 'what' happens in locomotion. However, few ask 'why' those motions occur as they do. The energetic and functional constraints acting on an animal require that locomotion should be metabolically 'cost effective' and this in large part determines the strategies available to accomplish the task. Understanding the gaits utilised, within the spectrum of gaits possible, and determination of the value of specific relationships among speed, stride length, stride frequency and morphology, depends on identifying the fundamental costs involved and the effects of different movement strategies on those costs. It is argued here that a fundamental loss associated with moving on limbs (centre of mass momentum and energy loss) and two costs involved with controlling and replacing that loss (muscular work of the supporting limb during stance and muscular work of repositioning the limbs during swing) interact to determine the cost trade-offs involved and the optimisation strategies available for each species and speed. These optimisation strategies are what has been observed and characterised as gait. Copyright © 2013 Elsevier Ltd. All rights reserved.

  5. Discrete Optimization Model for Vehicle Routing Problem with Scheduling Side Cosntraints

    NASA Astrophysics Data System (ADS)

    Juliandri, Dedy; Mawengkang, Herman; Bu'ulolo, F.

    2018-01-01

    Vehicle Routing Problem (VRP) is an important element of many logistic systems which involve routing and scheduling of vehicles from a depot to a set of customers node. This is a hard combinatorial optimization problem with the objective to find an optimal set of routes used by a fleet of vehicles to serve the demands a set of customers It is required that these vehicles return to the depot after serving customers’ demand. The problem incorporates time windows, fleet and driver scheduling, pick-up and delivery in the planning horizon. The goal is to determine the scheduling of fleet and driver and routing policies of the vehicles. The objective is to minimize the overall costs of all routes over the planning horizon. We model the problem as a linear mixed integer program. We develop a combination of heuristics and exact method for solving the model.

  6. Plasma levels of serotonin, gastrointestinal symptoms,and sleep problems in children with autism.

    PubMed

    Kheirouri, Sorayya; Kalejahi, Parinaz; Noorazar, Seyyed Gholamreza

    2016-12-20

    Autism is a neurodevelopmental disorder identified with higher frequency of serotonin abnormalities and gastrointestinal (GI) and sleep problems. This study aimed to evaluate the plasma levels of serotonin, GI symptoms, and sleep problems, and their relationship with autism severity in children with autism. Thirty-five children with autism and 31 healthy subjects were studied. GI problems, sleep disorders, and severity of disorder were assessed. Plasma serotonin was determined using ELISA. There was no significant association between GI problems and autism severity, but a significant positive correlation was seen between different indicators of sleep disorder and severity of autism. Plasma levels of serotonin were significantly higher in autistic children and a significant negative correlation was observed between plasma levels of serotonin and autism severity (r = -0.39, P = 0.02). Elevated plasma serotonin in autistic children and its negative correlation with disease severity may indicate involvement of the neurotransmitter in the neurophysiologic mechanism of autism.

  7. The problem solving skills and student generated representations (SGRs) profile of senior high school students in Bandung on the topic of work and energy

    NASA Astrophysics Data System (ADS)

    Alami, Y.; Sinaga, P.; Setiawan, A.

    2018-05-01

    Based on recommendations from the Physics Education literature recommend the use of multiple representations to help students solve problems. The use of some good representations is considered important to study physics, so many good motivations to learn how students use multiple representations while solving problems and to learn how to solve problems using multiple representations. This study aims to explore the profile of high school students’ problem solving abilities and this study is part of a larger research focus on improving this ability in students in physics. The data is needed to determine the appropriate treatment to be used in subsequent research. A purposive sampling technique was used in this study and a survey was conducted to collect data. 74 students from one high school in Bandung were involved in this research.

  8. The relationship between gambling attitudes, involvement, and problems in adolescence: Examining the moderating role of coping strategies and parenting styles.

    PubMed

    Dixon, Ramsay W; Youssef, George J; Hasking, Penelope; Yücel, Murat; Jackson, Alun C; Dowling, Nicki A

    2016-07-01

    Several factors are associated with an increased risk of adolescent problem gambling, including positive gambling attitudes, higher levels of gambling involvement, ineffective coping strategies and unhelpful parenting practices. It is less clear, however, how these factors interact or influence each other in the development of problem gambling behavior during adolescence. The aim of the current study was to simultaneously explore these predictors, with a particular focus on the extent to which coping skills and parenting styles may moderate the expected association between gambling involvement and gambling problems. Participants were 612 high school students. The data were analyzed using a zero-inflated Poisson (ZIP) regression model, controlling for gender. Although several variables predicted the number of symptoms associated with problem gambling, none of them predicted the probability of displaying any problem gambling. Gambling involvement fully mediated the relationship between positive gambling attitudes and gambling problem severity. There was a significant relationship between gambling involvement and problems at any level of problem focused coping, reference to others and inconsistent discipline. However, adaptive coping styles employed by adolescents and consistent disciplinary practices by parents were buffers of gambling problems at low levels of adolescent gambling involvement, but failed to protect adolescents when their gambling involvement was high. These findings indicate that research exploring the development of gambling problems is required and imply that coping and parenting interventions may have particular utility for adolescents who are at risk of development gambling problems but who are not gambling frequently. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Multirate sampled-data yaw-damper and modal suppression system design

    NASA Technical Reports Server (NTRS)

    Berg, Martin C.; Mason, Gregory S.

    1990-01-01

    A multirate control law synthesized algorithm based on an infinite-time quadratic cost function, was developed along with a method for analyzing the robustness of multirate systems. A generalized multirate sampled-data control law structure (GMCLS) was introduced. A new infinite-time-based parameter optimization multirate sampled-data control law synthesis method and solution algorithm were developed. A singular-value-based method for determining gain and phase margins for multirate systems was also developed. The finite-time-based parameter optimization multirate sampled-data control law synthesis algorithm originally intended to be applied to the aircraft problem was instead demonstrated by application to a simpler problem involving the control of the tip position of a two-link robot arm. The GMCLS, the infinite-time-based parameter optimization multirate control law synthesis method and solution algorithm, and the singular-value based method for determining gain and phase margins were all demonstrated by application to the aircraft control problem originally proposed for this project.

  10. A hybrid perturbation Galerkin technique with applications to slender body theory

    NASA Technical Reports Server (NTRS)

    Geer, James F.; Andersen, Carl M.

    1989-01-01

    A two-step hybrid perturbation-Galerkin method to solve a variety of applied mathematics problems which involve a small parameter is presented. The method consists of: (1) the use of a regular or singular perturbation method to determine the asymptotic expansion of the solution in terms of the small parameter; (2) construction of an approximate solution in the form of a sum of the perturbation coefficient functions multiplied by (unknown) amplitudes (gauge functions); and (3) the use of the classical Bubnov-Galerkin method to determine these amplitudes. This hybrid method has the potential of overcoming some of the drawbacks of the perturbation method and the Bubnov-Galerkin method when they are applied by themselves, while combining some of the good features of both. The proposed method is applied to some singular perturbation problems in slender body theory. The results obtained from the hybrid method are compared with approximate solutions obtained by other methods, and the degree of applicability of the hybrid method to broader problem areas is discussed.

  11. A hybrid perturbation Galerkin technique with applications to slender body theory

    NASA Technical Reports Server (NTRS)

    Geer, James F.; Andersen, Carl M.

    1987-01-01

    A two step hybrid perturbation-Galerkin method to solve a variety of applied mathematics problems which involve a small parameter is presented. The method consists of: (1) the use of a regular or singular perturbation method to determine the asymptotic expansion of the solution in terms of the small parameter; (2) construction of an approximate solution in the form of a sum of the perturbation coefficient functions multiplied by (unknown) amplitudes (gauge functions); and (3) the use of the classical Bubnov-Galerkin method to determine these amplitudes. This hybrid method has the potential of overcoming some of the drawbacks of the perturbation method and the Bubnov-Galerkin method when they are applied by themselves, while combining some of the good features of both. The proposed method is applied to some singular perturbation problems in slender body theory. The results obtained from the hybrid method are compared with approximate solutions obtained by other methods, and the degree of applicability of the hybrid method to broader problem areas is discussed.

  12. Engelhardt and children: the failure of libertarian bioethics in pediatric interactions.

    PubMed

    Hanson, Stephen

    2005-06-01

    In Engelhardt's secular bioethics, moral obligations derive from contracts and agreements between rational persons, and no infants or children and few adolescents meet Engelhardt's requirements for being a rational person. This is a problem, as one cannot have any direct secular moral obligations toward nonpersons such as infants and adolescents. The Engelhardtian concepts of ownership, indenture, and social personhood, which are meant to allow the theory to accommodate children and adolescents adequately, fail to give an Engelhardtian any actual means of determining the right action to take in difficult cases, even on his or her own terms. Thus, the theory is incapable of determining the morally correct action to take in cases involving children and therefore is unhelpful in dealing with moral questions involving children.

  13. Vis-NIR spectrometric determination of Brix and sucrose in sugar production samples using kernel partial least squares with interval selection based on the successive projections algorithm.

    PubMed

    de Almeida, Valber Elias; de Araújo Gomes, Adriano; de Sousa Fernandes, David Douglas; Goicoechea, Héctor Casimiro; Galvão, Roberto Kawakami Harrop; Araújo, Mario Cesar Ugulino

    2018-05-01

    This paper proposes a new variable selection method for nonlinear multivariate calibration, combining the Successive Projections Algorithm for interval selection (iSPA) with the Kernel Partial Least Squares (Kernel-PLS) modelling technique. The proposed iSPA-Kernel-PLS algorithm is employed in a case study involving a Vis-NIR spectrometric dataset with complex nonlinear features. The analytical problem consists of determining Brix and sucrose content in samples from a sugar production system, on the basis of transflectance spectra. As compared to full-spectrum Kernel-PLS, the iSPA-Kernel-PLS models involve a smaller number of variables and display statistically significant superiority in terms of accuracy and/or bias in the predictions. Published by Elsevier B.V.

  14. Introduction to cognitive processes of expert pilots.

    PubMed

    Adams, R J; Ericsson, A E

    2000-10-01

    This report addresses the historical problem that a very high percentage of accidents have been classified as involving "pilot error." Through extensive research since 1977, the Federal Aviation Administration determined that the predominant underlying cause of these types of accidents involved decisional problems or cognitive information processing. To attack these problems, Aeronautical Decision Making (ADM) training materials were developed and tested for ten years. Since the publication of the ADM training manuals in 1987, significant reductions in human performance error (HPE) accidents have been documented both in the U.S. and world wide. However, shortcomings have been observed in the use of these materials for recurrency training and in their relevance to more experienced pilots. The following discussion defines the differences between expert and novice decision makers from a cognitive information processing perspective, correlates the development of expert pilot cognitive processes with training and experience, and reviews accident scenarios which exemplify those processes. This introductory material is a necessary prerequisite to an understanding of how to formulate expert pilot decision making training innovations; and, to continue the record of improved safety through ADM training.

  15. Integrating NOE and RDC using sum-of-squares relaxation for protein structure determination.

    PubMed

    Khoo, Y; Singer, A; Cowburn, D

    2017-07-01

    We revisit the problem of protein structure determination from geometrical restraints from NMR, using convex optimization. It is well-known that the NP-hard distance geometry problem of determining atomic positions from pairwise distance restraints can be relaxed into a convex semidefinite program (SDP). However, often the NOE distance restraints are too imprecise and sparse for accurate structure determination. Residual dipolar coupling (RDC) measurements provide additional geometric information on the angles between atom-pair directions and axes of the principal-axis-frame. The optimization problem involving RDC is highly non-convex and requires a good initialization even within the simulated annealing framework. In this paper, we model the protein backbone as an articulated structure composed of rigid units. Determining the rotation of each rigid unit gives the full protein structure. We propose solving the non-convex optimization problems using the sum-of-squares (SOS) hierarchy, a hierarchy of convex relaxations with increasing complexity and approximation power. Unlike classical global optimization approaches, SOS optimization returns a certificate of optimality if the global optimum is found. Based on the SOS method, we proposed two algorithms-RDC-SOS and RDC-NOE-SOS, that have polynomial time complexity in the number of amino-acid residues and run efficiently on a standard desktop. In many instances, the proposed methods exactly recover the solution to the original non-convex optimization problem. To the best of our knowledge this is the first time SOS relaxation is introduced to solve non-convex optimization problems in structural biology. We further introduce a statistical tool, the Cramér-Rao bound (CRB), to provide an information theoretic bound on the highest resolution one can hope to achieve when determining protein structure from noisy measurements using any unbiased estimator. Our simulation results show that when the RDC measurements are corrupted by Gaussian noise of realistic variance, both SOS based algorithms attain the CRB. We successfully apply our method in a divide-and-conquer fashion to determine the structure of ubiquitin from experimental NOE and RDC measurements obtained in two alignment media, achieving more accurate and faster reconstructions compared to the current state of the art.

  16. Iterative solution of the inverse Cauchy problem for an elliptic equation by the conjugate gradient method

    NASA Astrophysics Data System (ADS)

    Vasil'ev, V. I.; Kardashevsky, A. M.; Popov, V. V.; Prokopev, G. A.

    2017-10-01

    This article presents results of computational experiment carried out using a finite-difference method for solving the inverse Cauchy problem for a two-dimensional elliptic equation. The computational algorithm involves an iterative determination of the missing boundary condition from the override condition using the conjugate gradient method. The results of calculations are carried out on the examples with exact solutions as well as at specifying an additional condition with random errors are presented. Results showed a high efficiency of the iterative method of conjugate gradients for numerical solution

  17. Knowledge-based nursing diagnosis

    NASA Astrophysics Data System (ADS)

    Roy, Claudette; Hay, D. Robert

    1991-03-01

    Nursing diagnosis is an integral part of the nursing process and determines the interventions leading to outcomes for which the nurse is accountable. Diagnoses under the time constraints of modern nursing can benefit from a computer assist. A knowledge-based engineering approach was developed to address these problems. A number of problems were addressed during system design to make the system practical extended beyond capture of knowledge. The issues involved in implementing a professional knowledge base in a clinical setting are discussed. System functions, structure, interfaces, health care environment, and terminology and taxonomy are discussed. An integrated system concept from assessment through intervention and evaluation is outlined.

  18. Autonomous sensor manager agents (ASMA)

    NASA Astrophysics Data System (ADS)

    Osadciw, Lisa A.

    2004-04-01

    Autonomous sensor manager agents are presented as an algorithm to perform sensor management within a multisensor fusion network. The design of the hybrid ant system/particle swarm agents is described in detail with some insight into their performance. Although the algorithm is designed for the general sensor management problem, a simulation example involving 2 radar systems is presented. Algorithmic parameters are determined by the size of the region covered by the sensor network, the number of sensors, and the number of parameters to be selected. With straight forward modifications, this algorithm can be adapted for most sensor management problems.

  19. The leather ankle lacer.

    PubMed Central

    Saltzman, C. L.; Shurr, D.; Kamp, J.; Cook, T. A.

    1995-01-01

    The purpose of this study was to evaluate the efficacy of a leather ankle lacer for treating painful problems of the ankle and hindfoot. The evaluation involved patient self assessment, clinical examination and radiographic determination of the effectiveness of the ankle lacer. Overall, patients had moderate pain relief with significant but not complete restriction of motion. Based on this study and our clinical experience, we find the leather ankle lacer to be a compliant and comfortable treatment strategy for patients with painful ankle and hindfoot problems who desire some retained motion. Images Figure 1A & B Figure 2 Figure 3 PMID:7634034

  20. Assessment of relative accuracy in the determination of organic matter concentrations in aquatic systems

    USGS Publications Warehouse

    Aiken, G.; Kaplan, L.A.; Weishaar, J.

    2002-01-01

    Accurate determinations of total (TOC), dissolved (DOC) and particulate (POC) organic carbon concentrations are critical for understanding the geochemical, environmental, and ecological roles of aquatic organic matter. Of particular significance for the drinking water industry, TOC measurements are the basis for compliance with US EPA regulations. The results of an interlaboratory comparison designed to identify problems associated with the determination of organic matter concentrations in drinking water supplies are presented. The study involved 31 laboratories and a variety of commercially available analytical instruments. All participating laboratories performed well on samples of potassium hydrogen phthalate (KHP), a compound commonly used as a standard in carbon analysis. However, problems associated with the oxidation of difficult to oxidize compounds, such as dodecylbenzene sulfonic acid and caffeine, were noted. Humic substances posed fewer problems for analysts. Particulate organic matter (POM) in the form of polystyrene beads, freeze-dried bacteria and pulverized leaf material were the most difficult for all analysts, with a wide range of performances reported. The POM results indicate that the methods surveyed in this study are inappropriate for the accurate determination of POC and TOC concentration. Finally, several analysts had difficulty in efficiently separating inorganic carbon from KHP solutions, thereby biasing DOC results.

  1. Self-Efficacy and Select Characteristics in Nurses Who Respond to a Pediatric Emergency

    ERIC Educational Resources Information Center

    McNeill, Nancy

    2016-01-01

    Nurses at a suburban northeastern U.S. community hospital reported that they felt unprepared to effectively respond to a pediatric emergency. Empirical data were not available to identify if this local problem was due to a lack of the nurses' self-confidence or if other factors were involved. The purpose of this study was to determine if there…

  2. Problem Based Learning Technique and Its Effect on Acquisition of Linear Programming Skills by Secondary School Students in Kenya

    ERIC Educational Resources Information Center

    Nakhanu, Shikuku Beatrice; Musasia, Amadalo Maurice

    2015-01-01

    The topic Linear Programming is included in the compulsory Kenyan secondary school mathematics curriculum at form four. The topic provides skills for determining best outcomes in a given mathematical model involving some linear relationship. This technique has found application in business, economics as well as various engineering fields. Yet many…

  3. Teachers' Attitudes Toward WebQuests as a Method of Teaching

    ERIC Educational Resources Information Center

    Perkins, Robert; McKnight, Margaret L.

    2005-01-01

    One of the latest uses of technology gaining popular status in education is the WebQuest, a process that involves students using the World Wide Web to solve a problem. The goals of this project are to: (a) determine if teachers are using WebQuests in their classrooms; (b) ascertain whether teachers feel WebQuests are effective for teaching…

  4. Methods of Establishing Occupational Skill Structure of Admissions in the System of Vocational Education

    ERIC Educational Resources Information Center

    Kosorukov, Oleg A.; Makarov, Alexander N.; Bagisbayev, Karmak B.

    2016-01-01

    The purpose of the study is to determine the business need for vocational training. This article gives a detailed analysis of the problem aimed at finding optimal occupational skill structure of training, which involves all kinds of positive effects in various areas of public life--from the economy up to the spiritual sphere of human life.…

  5. The Forgotten American. The President's Message to the Congress on Goals and Programs for American Indians (March 6, 1968).

    ERIC Educational Resources Information Center

    Johnson, Lyndon B.

    1968-01-01

    Emphasizing the need for a Federal-Indian partnership which promotes Indian self-help and Indian respect, this speech proposes: strengthened Federal leadership via a National Council on Indian Opportunity; Indian involvement in the determination of Indian problems and needs; enrollment of all Indian Children in a preschool program by 1971; funds…

  6. Finite difference time domain calculation of transients in antennas with nonlinear loads

    NASA Technical Reports Server (NTRS)

    Luebbers, Raymond J.; Beggs, John H.; Kunz, Karl S.; Chamberlin, Kent

    1991-01-01

    Determining transient electromagnetic fields in antennas with nonlinear loads is a challenging problem. Typical methods used involve calculating frequency domain parameters at a large number of different frequencies, then applying Fourier transform methods plus nonlinear equation solution techniques. If the antenna is simple enough so that the open circuit time domain voltage can be determined independently of the effects of the nonlinear load on the antennas current, time stepping methods can be applied in a straightforward way. Here, transient fields for antennas with more general geometries are calculated directly using Finite Difference Time Domain (FDTD) methods. In each FDTD cell which contains a nonlinear load, a nonlinear equation is solved at each time step. As a test case, the transient current in a long dipole antenna with a nonlinear load excited by a pulsed plane wave is computed using this approach. The results agree well with both calculated and measured results previously published. The approach given here extends the applicability of the FDTD method to problems involving scattering from targets, including nonlinear loads and materials, and to coupling between antennas containing nonlinear loads. It may also be extended to propagation through nonlinear materials.

  7. Determinants of quality management systems implementation in hospitals.

    PubMed

    Wardhani, Viera; Utarini, Adi; van Dijk, Jitse Pieter; Post, Doeke; Groothoff, Johan Willem

    2009-03-01

    To identify the problems and facilitating factors in the implementation of quality management system (QMS) in hospitals through a systematic review. A search strategy was performed on the Medline database for articles written in English published between 1992 and early 2006. Using the thesaurus terms 'Total Quality Management' and 'Quality Assurance Health Care', combined with the term 'hospital' and 'implement*', we identified 533 publications. The screening process was based on empirical articles describing organization-wide QMS implementation. Fourteen empirical articles fulfilled the inclusion criteria and were reviewed in this paper. An organization culture emphasizing standards and values associated with affiliation, teamwork and innovation, assumption of change and risk taking, play as the key success factor in QMS implementation. This culture needs to be supported by sufficient technical competence to apply a scientific problem-solving approach. A clear distribution of QMS function within the organizational structure is more important than establishing a formal quality structure. In addition to management leadership, physician involvement also plays an important role in implementing QMS. Six supporting and limiting factors determining QMS implementation are identified in this review. These are the organization culture, design, leadership for quality, physician involvement, quality structure and technical competence.

  8. [Hydatid Cyst Cases with Different Localization: Region of Erzurum].

    PubMed

    Demirci, Elif; Altun, Eren; Çalık, Muhammet; Durur Subaşı, Irmak; Şipal, Sare; Gündoğdu, Özge Beyza

    2015-06-01

    In this study it is aimed to contribute in determination of geographic distribution of Hydatid Cysts in Turkey and to emphasize the clinic chaos of Hydatid Cysts cases found in various localizations, by indicating the prevalence of Hydatid Cysts in our region. It is evaluated that the cases diagnosed as Hydatid Cysts in Atatürk University Medical Faculty Pathology Depatment/Erzurum laboratories between 2003-2013; in terms of their age, gender, organ involvement and histopathologic detail. In our study, 459 Hydatid Cysts cases are defined. The most common localizations of cases are determined as liver (n:280, 61%) and lung (n:86, 18,7%). Those are followed by the kidney (n:12, 2,6%), brain (n:12, 2,6%) and spleen (n:9, 2.3%). Multi-organ involvement is observed in 31 cases (6.7%), in 10 (2.2%) cases co-occurence of liver and lung is determined. Unusual organ involvement is observed in 64 cases (13.9%) while the liver and lung is not involved. Hydatid Cysts is an important health issue which is endemically seen in our region. It can be observed in various localizations of human body, other than the liver and lung. Those various localizations lie behind the serious diagnostic problems in endemic regions.

  9. Psychopathology in pediatric epilepsy: role of antiepileptic drugs.

    PubMed

    Caplan, Rochelle

    2012-01-01

    Children with epilepsy are usually treated with antiepileptic drugs (AEDS). Some AEDs adversely affect behavior in susceptible children. Since psychiatric comorbidity is prevalent in pediatric epilepsy, this paper attempts to disentangle these AED side effects from the psychopathology associated with this illness. It first outlines the clinical and methodological problems involved in determining if AEDs contribute to the behavior and emotional problems of children with epilepsy. It then presents research evidence for and against the role AEDs play in the psychopathology of children with epilepsy, and outlines how future studies might investigate this problem. A brief description of how to clinically separate out AED effects from the complex illness-related and psychosocial factors that contribute to the behavior difficulties of children with epilepsy concludes the paper.

  10. How to save distressed IDS-physician marriages: a case study.

    PubMed

    Collins, H; Johnson, B A

    1998-04-01

    A hospital-driven IDS that encounters serious problems resulting from ownership of a physician practice should address those problems by focusing on three core areas: vision and leadership, effectiveness of operations, and physician compensation arrangements. If changes in these areas do not lead to improvements, the IDS may need to consider organizational restructuring. In one case study, a hospital-driven IDS faced the problem of owning a poorly performing MSO with a captive physician group. The IDS's governing board determined that the organization lacked effective communication with the physicians and that realization of the organization's vision would require greater physician involvement in organizational decision making. The organization is expected to undergo some corporate reorganization in which physicians will acquire an equity interest in the enterprise.

  11. Best possible medication history for hemodialysis patients obtained by a pharmacy technician.

    PubMed

    Leung, Marianna; Jung, Joanne; Lau, Wynnie; Kiaii, Mercedeh; Jung, Beverly

    2009-09-01

    Outpatients undergoing hemodialysis are at high risk for adverse drug events. Limited resources make it challenging for pharmacists to routinely obtain a best possible medication history (BPMH). The primary objective was to determine whether, for patients undergoing hemodialysis, a pharmacy technician has the skills to obtain a BPMH that would allow a pharmacist to identify drug-related problems. The secondary objectives were to determine the number and types of medication discrepancies and drug-related problems identified and the time required by the technician to complete the BPMH. All patients treated in the hemodialysis unit during the study period were included, except for those who required an interpreter or were unable to participate in an in-person interview. A single technician was taught how to interview patients according to a structured format. For each patient, the technician's BMPH was verified by a pharmacist. The agreement rate between technician and pharmacists was determined, along with the number and types of discrepancies and drug-related problems identified. The technician interviewed 99 patients. Of the 1334 medication orders reviewed, the technician and pharmacists agreed on all but 15 (agreement rate 98.9%). A total of 358 medication discrepancies were noted for 93 patients (3.8 discrepancies per patient). Of these, 210 (59%) were undocumented intentional discrepancies, and 148 (41%) were unintentional discrepancies (most commonly errors of commission). Of the 135 drug-related problems identified, the majority involved dosing problems or nonadherence. The technician required an average of 17 min for each interview. An adequately trained technician was capable of interviewing patients to create a BPMH. A variety of medication discrepancies and drug-related problems were identified. Generation of a BPMH by a technician is a useful approach allowing pharmacists to identify drug-related problems.

  12. Best Possible Medication History for Hemodialysis Patients Obtained by a Pharmacy Technician

    PubMed Central

    Leung, Marianna; Jung, Joanne; Lau, Wynnie; Kiaii, Mercedeh; Jung, Beverly

    2009-01-01

    Background: Outpatients undergoing hemodialysis are at high risk for adverse drug events. Limited resources make it challenging for pharmacists to routinely obtain a best possible medication history (BPMH). Objectives: The primary objective was to determine whether, for patients undergoing hemodialysis, a pharmacy technician has the skills to obtain a BPMH that would allow a pharmacist to identify drug-related problems. The secondary objectives were to determine the number and types of medication discrepancies and drug-related problems identified and the time required by the technician to complete the BPMH. Methods: All patients treated in the hemodialysis unit during the study period were included, except for those who required an interpreter or were unable to participate in an in-person interview. A single technician was taught how to interview patients according to a structured format. For each patient, the technician’s BMPH was verified by a pharmacist. The agreement rate between technician and pharmacists was determined, along with the number and types of discrepancies and drug-related problems identified. Results: The technician interviewed 99 patients. Of the 1334 medication orders reviewed, the technician and pharmacists agreed on all but 15 (agreement rate 98.9%). A total of 358 medication discrepancies were noted for 93 patients (3.8 discrepancies per patient). Of these, 210 (59%) were undocumented intentional discrepancies, and 148 (41%) were unintentional discrepancies (most commonly errors of commission). Of the 135 drug-related problems identified, the majority involved dosing problems or nonadherence. The technician required an average of 17 min for each interview. Conclusion: An adequately trained technician was capable of interviewing patients to create a BPMH. A variety of medication discrepancies and drug-related problems were identified. Generation of a BPMH by a technician is a useful approach allowing pharmacists to identify drug-related problems. PMID:22478921

  13. Multigrid one shot methods for optimal control problems: Infinite dimensional control

    NASA Technical Reports Server (NTRS)

    Arian, Eyal; Taasan, Shlomo

    1994-01-01

    The multigrid one shot method for optimal control problems, governed by elliptic systems, is introduced for the infinite dimensional control space. ln this case, the control variable is a function whose discrete representation involves_an increasing number of variables with grid refinement. The minimization algorithm uses Lagrange multipliers to calculate sensitivity gradients. A preconditioned gradient descent algorithm is accelerated by a set of coarse grids. It optimizes for different scales in the representation of the control variable on different discretization levels. An analysis which reduces the problem to the boundary is introduced. It is used to approximate the two level asymptotic convergence rate, to determine the amplitude of the minimization steps, and the choice of a high pass filter to be used when necessary. The effectiveness of the method is demonstrated on a series of test problems. The new method enables the solutions of optimal control problems at the same cost of solving the corresponding analysis problems just a few times.

  14. Optimal Control of Thermo--Fluid Phenomena in Variable Domains

    NASA Astrophysics Data System (ADS)

    Volkov, Oleg; Protas, Bartosz

    2008-11-01

    This presentation concerns our continued research on adjoint--based optimization of viscous incompressible flows (the Navier--Stokes problem) coupled with heat conduction involving change of phase (the Stefan problem), and occurring in domains with variable boundaries. This problem is motivated by optimization of advanced welding techniques used in automotive manufacturing, where the goal is to determine an optimal heat input, so as to obtain a desired shape of the weld pool surface upon solidification. We argue that computation of sensitivities (gradients) in such free--boundary problems requires the use of the shape--differential calculus as a key ingredient. We also show that, with such tools available, the computational solution of the direct and inverse (optimization) problems can in fact be achieved in a similar manner and in a comparable computational time. Our presentation will address certain mathematical and computational aspects of the method. As an illustration we will consider the two--phase Stefan problem with contact point singularities where our approach allows us to obtain a thermodynamically consistent solution.

  15. The determinants of the antibiotic resistance process.

    PubMed

    Franco, Beatriz Espinosa; Altagracia Martínez, Marina; Sánchez Rodríguez, Martha A; Wertheimer, Albert I

    2009-01-01

    The use of antibiotic drugs triggers a complex interaction involving many biological, sociological, and psychological determinants. Resistance to antibiotics is a serious worldwide problem which is increasing and has implications for morbidity, mortality, and health care both in hospitals and in the community. To analyze current research on the determinants of antibiotic resistance and comprehensively review the main factors in the process of resistance in order to aid our understanding and assessment of this problem. We conducted a MedLine search using the key words "determinants", "antibiotic", and "antibiotic resistance" to identify publications between 1995 and 2007 on the determinants of antibiotic resistance. Publications that did not address the determinants of antibiotic resistance were excluded. The process and determinants of antibiotic resistance are described, beginning with the development of antibiotics, resistance and the mechanisms of resistance, sociocultural determinants of resistance, the consequences of antibiotic resistance, and alternative measures proposed to combat antibiotic resistance. Analysis of the published literature identified the main determinants of antibiotic resistance as irrational use of antibiotics in humans and animal species, insufficient patient education when antibiotics are prescribed, lack of guidelines for treatment and control of infections, lack of scientific information for physicians on the rational use of antibiotics, and lack of official government policy on the rational use of antibiotics in public and private hospitals.

  16. Problem drinking and the dimension of involvement with drugs: a Guttman scalogram analysis of adolescent drug use.

    PubMed Central

    Donovan, J E; Jessor, R

    1983-01-01

    Analyses of data from two nationwide surveys of high school students, one carried out in 1974 and the other in 1978, suggest that problem drinking may be seen as yet another step along an underlying dimension of involvement with both licit and illicit drugs. The dimension of involvement with drugs consists of the following levels: nonuse of alcohol or illicit drugs; nonproblem use of alcohol; marijuana use; problem drinking; use of pills (amphetamines, barbiturates, hallucinogenic drugs); and the use of "hard drugs" such as cocaine or heroin. The dimension possesses excellent Guttman-scale properties in both national samples as well as in subsamples differing in gender and ethnic background. The ordering of the levels of involvement was confirmed by the ordering of the alcohol-drug involvement groups based on their mean scores on measures of psychosocial proneness for involvement in problem behavior. The excessive use of a licit drug, i.e., problem drinking, appears to indicate greater involvement in drug use than does the use of an illicit drug, marijuana. This finding points to the importance of distinguishing between use and problem use of drugs in efforts to understand adolescent drug involvement. PMID:6837819

  17. Continuation of probability density functions using a generalized Lyapunov approach

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

    Baars, S., E-mail: s.baars@rug.nl; Viebahn, J.P., E-mail: viebahn@cwi.nl; Mulder, T.E., E-mail: t.e.mulder@uu.nl

    Techniques from numerical bifurcation theory are very useful to study transitions between steady fluid flow patterns and the instabilities involved. Here, we provide computational methodology to use parameter continuation in determining probability density functions of systems of stochastic partial differential equations near fixed points, under a small noise approximation. Key innovation is the efficient solution of a generalized Lyapunov equation using an iterative method involving low-rank approximations. We apply and illustrate the capabilities of the method using a problem in physical oceanography, i.e. the occurrence of multiple steady states of the Atlantic Ocean circulation.

  18. SDS-Polyacrylamide Electrophoresis and Western Blotting Applied to the Study of Asthma.

    PubMed

    García-Solaesa, Virginia; Abad, Sara Ciria

    2016-01-01

    Western blotting is used to analyze proteins after being separated by electrophoresis and subsequently electro-transferred to a membrane. Once immobilized, a specific protein can be identified through its reaction with a labeled antibody or antigen. It is a methodology commonly used in biomedical research such as asthma studies, to assess the pathways of inflammatory mediators involved in the disease.Here, we describe an example of western blotting to determine the factors involved in asthma. In this chapter, the methodology of western blotting is reviewed, paying attention on potential problems and giving interesting recommendations.

  19. Human immunodeficiency virus infection and diffuse polyneuropathy. Implications for rehabilitation medicine.

    PubMed Central

    Mukand, J. A.

    1991-01-01

    Patients at various stages of human immunodeficiency virus (HIV) infection require rehabilitation services. These patients present problems for each of the disciplines in a rehabilitation team, and all team members must confront the psychosocial and ethical issues involved with the disease. Patients with HIV infection may have polyneuropathy with multisystem involvement, including dysphagia, autonomic dysfunction, respiratory failure, bowel and bladder dysfunction, generalized weakness, a painful sensory neuropathy, and depression. Guidelines are presented for determining if inpatient rehabilitation or other settings are appropriate. Case management is a valuable strategy for the rehabilitation of patients with this complicated disorder. PMID:1866948

  20. Propeller Study. Part 2: the Design of Propellers for Minimum Noise

    NASA Technical Reports Server (NTRS)

    Ormsbee, A. I.; Woan, C. J.

    1977-01-01

    The design of propellers which are efficient and yet produce minimum noise requires accurate determinations of both the flow over the propeller. Topics discussed in relating aerodynamic propeller design and propeller acoustics include the necessary approximations and assumptions involved, the coordinate systems and their transformations, the geometry of the propeller blade, and the problem formulations including the induced velocity, required in the determination of mean lines of blade sections, and the optimization of propeller noise. The numerical formulation for the lifting-line model are given. Some applications and numerical results are included.

  1. Peer-led problem-based learning in interprofessional education of health professions students.

    PubMed

    Lehrer, Michael D; Murray, Samuel; Benzar, Ruth; Stormont, Ryan; Lightfoot, Megan; Hafertepe, Michael; Welch, Gabrielle; Peters, Nicholas; Maio, Anna

    2015-01-01

    The role of peer teachers in interprofessional education has not been extensively studied. This study is designed to determine if peer-teacher-led problem-based seminars can influence medical and pharmacy students' perceptions of interprofessional education. Undergraduate medical and pharmacy students participated in one-hour problem-based learning seminars held over the course of 16 weeks. A case-control study design was used to compare perceptions of interprofessional education between students who participated in seminars and students who did not participate in seminars. The validated Interdisciplinary Education Perception Scale (IEPS) was used to assess perceptions of interprofessional education and was distributed to medical and pharmacy students at the conclusion of 16 weeks of seminars. A two-tailed t-test was used to determine significance between groups. A survey was also distributed to all students regarding perceived barriers to involvement in interprofessional education training. In total, 97 students responded to IEPS (62 medical, 35 pharmacy). Data showed significantly higher perception of professional cooperation among medical students (p=0.006) and pharmacy students (p=0.02) who attended interprofessional seminars compared to those who did not attend. One hundred and nine students responded to the survey regarding perceived barriers to interprofessional education, with the two most common barriers being: 'I am not aware of interprofessional education opportunities' (61.5%) and 'I do not have time to participate' (52.3%). Based on this data we believe peer-teacher-led problem-based interprofessional seminars can be used to increase medical and pharmacy students' perceived need for professional cooperation. Currently, major barriers to interprofessional education involvement are awareness and time commitment. Undergraduate health professions education can incorporate student-led seminars to improve interprofessional education.

  2. Peer-led problem-based learning in interprofessional education of health professions students.

    PubMed

    Lehrer, Michael D; Murray, Samuel; Benzar, Ruth; Stormont, Ryan; Lightfoot, Megan; Hafertepe, Michael; Welch, Gabrielle; Peters, Nicholas; Maio, Anna

    2015-01-01

    Background The role of peer teachers in interprofessional education has not been extensively studied. This study is designed to determine if peer-teacher-led problem-based seminars can influence medical and pharmacy students' perceptions of interprofessional education. Methods Undergraduate medical and pharmacy students participated in one-hour problem-based learning seminars held over the course of 16 weeks. A case-control study design was used to compare perceptions of interprofessional education between students who participated in seminars and students who did not participate in seminars. The validated Interdisciplinary Education Perception Scale (IEPS) was used to assess perceptions of interprofessional education and was distributed to medical and pharmacy students at the conclusion of 16 weeks of seminars. A two-tailed t-test was used to determine significance between groups. A survey was also distributed to all students regarding perceived barriers to involvement in interprofessional education training. Results In total, 97 students responded to IEPS (62 medical, 35 pharmacy). Data showed significantly higher perception of professional cooperation among medical students (p=0.006) and pharmacy students (p=0.02) who attended interprofessional seminars compared to those who did not attend. One hundred and nine students responded to the survey regarding perceived barriers to interprofessional education, with the two most common barriers being: 'I am not aware of interprofessional education opportunities' (61.5%) and 'I do not have time to participate' (52.3%). Conclusion Based on this data we believe peer-teacher-led problem-based interprofessional seminars can be used to increase medical and pharmacy students' perceived need for professional cooperation. Currently, major barriers to interprofessional education involvement are awareness and time commitment. Undergraduate health professions education can incorporate student-led seminars to improve interprofessional education.

  3. Structured Uncertainty Bound Determination From Data for Control and Performance Validation

    NASA Technical Reports Server (NTRS)

    Lim, Kyong B.

    2003-01-01

    This report attempts to document the broad scope of issues that must be satisfactorily resolved before one can expect to methodically obtain, with a reasonable confidence, a near-optimal robust closed loop performance in physical applications. These include elements of signal processing, noise identification, system identification, model validation, and uncertainty modeling. Based on a recently developed methodology involving a parameterization of all model validating uncertainty sets for a given linear fractional transformation (LFT) structure and noise allowance, a new software, Uncertainty Bound Identification (UBID) toolbox, which conveniently executes model validation tests and determine uncertainty bounds from data, has been designed and is currently available. This toolbox also serves to benchmark the current state-of-the-art in uncertainty bound determination and in turn facilitate benchmarking of robust control technology. To help clarify the methodology and use of the new software, two tutorial examples are provided. The first involves the uncertainty characterization of a flexible structure dynamics, and the second example involves a closed loop performance validation of a ducted fan based on an uncertainty bound from data. These examples, along with other simulation and experimental results, also help describe the many factors and assumptions that determine the degree of success in applying robust control theory to practical problems.

  4. Measuring Family Problem Solving: The Family Problem Solving Diary.

    ERIC Educational Resources Information Center

    Kieren, Dianne K.

    The development and use of the family problem-solving diary are described. The diary is one of several indicators and measures of family problem-solving behavior. It provides a record of each person's perception of day-to-day family problems (what the problem concerns, what happened, who got involved, what those involved did, how the problem…

  5. Probability bounds analysis for nonlinear population ecology models.

    PubMed

    Enszer, Joshua A; Andrei Măceș, D; Stadtherr, Mark A

    2015-09-01

    Mathematical models in population ecology often involve parameters that are empirically determined and inherently uncertain, with probability distributions for the uncertainties not known precisely. Propagating such imprecise uncertainties rigorously through a model to determine their effect on model outputs can be a challenging problem. We illustrate here a method for the direct propagation of uncertainties represented by probability bounds though nonlinear, continuous-time, dynamic models in population ecology. This makes it possible to determine rigorous bounds on the probability that some specified outcome for a population is achieved, which can be a core problem in ecosystem modeling for risk assessment and management. Results can be obtained at a computational cost that is considerably less than that required by statistical sampling methods such as Monte Carlo analysis. The method is demonstrated using three example systems, with focus on a model of an experimental aquatic food web subject to the effects of contamination by ionic liquids, a new class of potentially important industrial chemicals. Copyright © 2015. Published by Elsevier Inc.

  6. D-Optimal Experimental Design for Contaminant Source Identification

    NASA Astrophysics Data System (ADS)

    Sai Baba, A. K.; Alexanderian, A.

    2016-12-01

    Contaminant source identification seeks to estimate the release history of a conservative solute given point concentration measurements at some time after the release. This can be mathematically expressed as an inverse problem, with a linear observation operator or a parameter-to-observation map, which we tackle using a Bayesian approach. Acquisition of experimental data can be laborious and expensive. The goal is to control the experimental parameters - in our case, the sparsity of the sensors, to maximize the information gain subject to some physical or budget constraints. This is known as optimal experimental design (OED). D-optimal experimental design seeks to maximize the expected information gain, and has long been considered the gold standard in the statistics community. Our goal is to develop scalable methods for D-optimal experimental designs involving large-scale PDE constrained problems with high-dimensional parameter fields. A major challenge for the OED, is that a nonlinear optimization algorithm for the D-optimality criterion requires repeated evaluation of objective function and gradient involving the determinant of large and dense matrices - this cost can be prohibitively expensive for applications of interest. We propose novel randomized matrix techniques that bring down the computational costs of the objective function and gradient evaluations by several orders of magnitude compared to the naive approach. The effect of randomized estimators on the accuracy and the convergence of the optimization solver will be discussed. The features and benefits of our new approach will be demonstrated on a challenging model problem from contaminant source identification involving the inference of the initial condition from spatio-temporal observations in a time-dependent advection-diffusion problem.

  7. Counterfeit medicines in Peru: a retrospective review (1997–2014)

    PubMed Central

    Medina, Edwin; Bel, Elvira; Suñé, Josep María

    2016-01-01

    Objective To consolidate and assess information on counterfeit medicines subject to pharmaceutical alerts issued by the Peruvian Medicines Regulatory Authority over 18 years (1997–2014) of health monitoring and enforcement. Design A retrospective review of drug alerts. Setting A search of the website of the General Directorate of Medicines, Supplies and Drugs (DIGEMID) of the Ministry of Health of Peru for drug alerts issued between 1997 and 2014. Eligibility criteria Drug alerts related to counterfeit medicines. Results A total of 669 DIGEMID alerts were issued during the study period, 354 (52.91%) of which cover 1738 cases of counterfeit medicines (many alerts deal with several cases at a time). 1010 cases (58.11%) involved pharmaceutical establishments and 349 (20.08%) involved non-pharmaceutical commercial outlets. In 126 cases (7.25%), counterfeit medicines were seized in an unauthorised trade (without any marketing authorisation); in 253 cases (14.56%) the type of establishment or business associated with the seized product was not identified. Conclusions Counterfeit medicines are a serious public health problem in Peru. A review of the data cannot determine whether counterfeit medicines in Peru increased during the study period, or if monitoring by different government health agencies highlighted the magnitude of the problem by providing more evidence. The problem is clearly structural, since the majority of cases (58.11% of the total) were detected in legitimate supply chains. Most counterfeit medicines involve staple pharmaceutical products and common dosage forms. Considerable work remains to be done to control the serious problem of counterfeit medicines in Peru. PMID:27044580

  8. The Relationship of Financial Incentives and Consumers' Willingness to Disclose Information to eCommerce Marketers

    ERIC Educational Resources Information Center

    Pourhosseini, Parissa

    2009-01-01

    In this study the problem examined was a lack of research based information on the degree to which incentives can be used to encourage consumers to volunteer private information. The purpose of this study was to determine if monetary incentives would be a beneficial means to increase consumers' involvement in eCommerce and thereby boost the growth…

  9. AHPCRC - Army High Performance Computing Research Center

    DTIC Science & Technology

    2010-01-01

    shielding fabrics. Contact with a projectile induces electromagnetic forces on the fabric that can cause the projectile to rotate , making it less...other AHPCRC projects in need of optimization techniques. A major focus of this research addresses solving partial differential equation ( PDE ...plat- forms. One such problem is the determination of optimal wing shapes and motions. Work in progress involves coupling the PDE -solver AERO-F and

  10. A Survey of CAD/CAM Technology Applications in the U.S. Shipbuilding Industry

    DTIC Science & Technology

    1984-01-01

    operation for drafting. Computer Aided Engineering (CAE) analysis is used primarily to determine the validity of design characteristics and produc- tion...include time standard generation, sea trial analysis , and group Systems integration While no systems surveyed Aided Design (CAD) is the technology... analysis . is the largest problem involving software packages. are truly integrated, many are interfaced. Computer most interfaced category with links

  11. Involvement of Lipid Metabolism in the Action of Phospholipase A2 Neurotoxins

    DTIC Science & Technology

    1993-12-03

    saturated or unsaturated fatty acid on phospholipid hydrolysis d) determine effects of BSA...either unsaturated (18:2) or saturated (18:0) fatty acids . A major problem encountered in our studies at 100 nM toxin concentrations that we have now...examined. In contrast to the liberation of unsaturated fatty acids , the total (pellet plus supernatant) saturated fatty acids produced was greater for

  12. Analysis of general aviation single-pilot IFR incident data obtained from the NASA Aviation Safety Reporting System

    NASA Technical Reports Server (NTRS)

    Bergeron, H. P.

    1983-01-01

    An analysis of incident data obtained from the NASA Aviation Safety Reporting System (ASRS) has been made to determine the problem areas in general aviation single-pilot IFR (SPIFR) operations. The Aviation Safety Reporting System data base is a compilation of voluntary reports of incidents from any person who has observed or been involved in an occurrence which was believed to have posed a threat to flight safety. This paper examines only those reported incidents specifically related to general aviation single-pilot IFR operations. The frequency of occurrence of factors related to the incidents was the criterion used to define significant problem areas and, hence, to suggest where research is needed. The data was cataloged into one of five major problem areas: (1) controller judgment and response problems, (2) pilot judgment and response problems, (3) air traffic control (ATC) intrafacility and interfacility conflicts, (4) ATC and pilot communication problems, and (5) IFR-VFR conflicts. In addition, several points common to all or most of the problems were observed and reported. These included human error, communications, procedures and rules, and work load.

  13. Fleet Assignment Using Collective Intelligence

    NASA Technical Reports Server (NTRS)

    Antoine, Nicolas E.; Bieniawski, Stefan R.; Kroo, Ilan M.; Wolpert, David H.

    2004-01-01

    Product distribution theory is a new collective intelligence-based framework for analyzing and controlling distributed systems. Its usefulness in distributed stochastic optimization is illustrated here through an airline fleet assignment problem. This problem involves the allocation of aircraft to a set of flights legs in order to meet passenger demand, while satisfying a variety of linear and non-linear constraints. Over the course of the day, the routing of each aircraft is determined in order to minimize the number of required flights for a given fleet. The associated flow continuity and aircraft count constraints have led researchers to focus on obtaining quasi-optimal solutions, especially at larger scales. In this paper, the authors propose the application of this new stochastic optimization algorithm to a non-linear objective cold start fleet assignment problem. Results show that the optimizer can successfully solve such highly-constrained problems (130 variables, 184 constraints).

  14. On the the Contact Lens Problem: Modeling Rigid and Elastic Beams on Thin Films

    NASA Astrophysics Data System (ADS)

    Trinh, Philippe; Wilson, Stephen; Stone, Howard

    2011-11-01

    Generally, contact lenses are prescribed by the practitioner to fit each individual patient's eye, but these fitting-philosophies are based on empirical studies and a certain degree of trial-and-error. A badly fitted lens can cause a range of afflictions, which varies from mild dry-eye-discomfort, to more serious corneal diseases. Thus, at this heart of this problem, is the question of how a rigid or elastic plate interacts with the free-surface of a thin viscous film. In this talk, we present several mathematical models for the study of these plate-and-fluid problems. Asymptotic and numerical results are described, and we explain the role of elasticity, surface tension, viscosity, and pressure in determining the equilibrium solutions. Finally, we discuss the implications of our work on the contact lens problem, as well as on other coating processes which involve elastic substrates.

  15. An inverse model for a free-boundary problem with a contact line: Steady case

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

    Volkov, Oleg; Protas, Bartosz

    2009-07-20

    This paper reformulates the two-phase solidification problem (i.e., the Stefan problem) as an inverse problem in which a cost functional is minimized with respect to the position of the interface and subject to PDE constraints. An advantage of this formulation is that it allows for a thermodynamically consistent treatment of the interface conditions in the presence of a contact point involving a third phase. It is argued that such an approach in fact represents a closure model for the original system and some of its key properties are investigated. We describe an efficient iterative solution method for the Stefan problemmore » formulated in this way which uses shape differentiation and adjoint equations to determine the gradient of the cost functional. Performance of the proposed approach is illustrated with sample computations concerning 2D steady solidification phenomena.« less

  16. Finite Element Modeling of a Cylindrical Contact Using Hertzian Assumptions

    NASA Technical Reports Server (NTRS)

    Knudsen, Erik

    2003-01-01

    The turbine blades in the high-pressure fuel turbopump/alternate turbopump (HPFTP/AT) are subjected to hot gases rapidly flowing around them. This flow excites vibrations in the blades. Naturally, one has to worry about resonance, so a damping device was added to dissipate some energy from the system. The foundation is now laid for a very complex problem. The damper is in contact with the blade, so now there are contact stresses (both normal and tangential) to contend with. Since these stresses can be very high, it is not all that difficult to yield the material. Friction is another non-linearity and the blade is made out of a Nickel-based single-crystal superalloy that is orthotropic. A few approaches exist to solve such a problem and computer models, using contact elements, have been built with friction, plasticity, etc. These models are quite cumbersome and require many hours to solve just one load case and material orientation. A simpler approach is required. Ideally, the model should be simplified so the analysis can be conducted faster. When working with contact problems determining the contact patch and the stresses in the material are the main concerns. Closed-form solutions for non-conforming bodies, developed by Hertz, made out of isotropic materials are readily available. More involved solutions for 3-D cases using different materials are also available. The question is this: can Hertzian1 solutions be applied, or superimposed, to more complicated problems-like those involving anisotropic materials? That is the point of the investigation here. If these results agree with the more complicated computer models, then the analytical solutions can be used in lieu of the numerical solutions that take a very long time to process. As time goes on, the analytical solution will eventually have to include things like friction and plasticity. The models in this report use no contact elements and are essentially an applied load problem using Hertzian assumptions to determine the contact patch dimensions.

  17. Father Involvement and Behavior Problems among Preadolescents at Risk of Maltreatment

    PubMed Central

    Yoon, Susan; Bellamy, Jennifer L.; Kim, Wonhee; Yoon, Dalhee

    2018-01-01

    Although there is a well-established connection between father involvement and children’s positive behavioral development in general, this relation has been understudied in more vulnerable and high-risk populations. The aims of this study were to examine how the quantity (i.e., the amount of shared activities) and quality (i.e., perceived quality of the father-child relationship) of father involvement are differently related to internalizing and externalizing behavior problems among preadolescents at risk of maltreatment and test if these associations are moderated by father type and child maltreatment. A secondary data analysis was conducted using data from the Longitudinal Studies of Child Abuse and Neglect (LONGSCAN). Generalized estimating equations analysis was performed on a sample of 499 preadolescents aged 12 years. The results indicated that higher quality of father involvement was associated with lower levels of internalizing and externalizing behavior problems whereas greater quantity of father involvement was associated with higher levels of internalizing and externalizing behavior problems. The positive association between the quantity of father involvement and behavior problems was stronger in adolescents who were physically abused by their father. The association between father involvement and behavior problems did not differ by the type of father co-residing in the home. The findings suggest that policies and interventions aimed at improving the quality of fathers’ relationships and involvement with their children may be helpful in reducing behavior problems in adolescents at risk of maltreatment. PMID:29491703

  18. Potential flow about arbitrary biplane wing sections

    NASA Technical Reports Server (NTRS)

    Garrick, I E

    1937-01-01

    A rigorous treatment is given of the problem of determining the two-dimensional potential flow around arbitrary biplane cellules. The analysis involves the use of elliptic functions and is sufficiently general to include the effects of such elements as the section shapes, the chord ratio, gap, stagger, and decalage, which elements may be specified arbitrarily. The flow problem is resolved by making use of the methods of conformal representation. Thus the solution of the problem of transforming conformally two arbitrary contours into two circles is expressed by a pair of simultaneous integral equations, for which a method of numerical solution is outlined. As an example of the numerical process, the pressure distribution over certain arrangements of the NACA 4412 airfoil in biplane combinations is presented and compared with the monoplane pressure distribution.

  19. Numerical modeling of subsurface communication

    NASA Astrophysics Data System (ADS)

    Burke, G. J.; Dease, C. G.; Didwall, E. M.; Lytle, R. J.

    1985-02-01

    Techniques are described for numerical modeling of through-the-Earth communication. The basic problem considered is evaluation of the field at a surface or airborne station due to an antenna buried in the Earth. Equations are given for the field of a point source in a homogeneous or stratified earth. These expressions involve infinite integrals over wave number, sometimes known as Sommerfield integrals. Numerical techniques used for evaluating these integrals are outlined. The problem of determining the current on a real antenna in the Earth, including the effect of insulation, is considered. Results are included for the fields of a point source in homogeneous and stratified earths and the field of a finite insulated dipole. The results are for electromagnetic propagation in the ELF-VLF range, but the codes also can address propagation problems at higher frequencies.

  20. Diagnosis and Management of Subacute Ruminal Acidosis in Dairy Herds.

    PubMed

    Oetzel, Garrett R

    2017-11-01

    Subacute ruminal acidosis (SARA) is a common problem in lactating dairy cows that causes chronic health problems, impairs feed efficiency, and increases the environmental impact of milk production. Low ruminal pH appears to be the main instigator of the pathophysiology of SARA, although other metabolites produced in the rumen may be involved. Inflammatory responses to SARA are variable but important determinants of a cow's response to SARA. SARA can be diagnosed at the herd level by integrating information about clinical signs and on-farm measures of ruminal pH. Prevention of SARA requires excellent feeding management and proper diet formulation. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. NASA Formal Methods Workshop, 1990

    NASA Technical Reports Server (NTRS)

    Butler, Ricky W. (Compiler)

    1990-01-01

    The workshop brought together researchers involved in the NASA formal methods research effort for detailed technical interchange and provided a mechanism for interaction with representatives from the FAA and the aerospace industry. The workshop also included speakers from industry to debrief the formal methods researchers on the current state of practice in flight critical system design, verification, and certification. The goals were: define and characterize the verification problem for ultra-reliable life critical flight control systems and the current state of practice in industry today; determine the proper role of formal methods in addressing these problems, and assess the state of the art and recent progress toward applying formal methods to this area.

  2. Fleet Assignment Using Collective Intelligence

    NASA Technical Reports Server (NTRS)

    Antoine, Nicolas E.; Bieniawski, Stefan R.; Kroo, Ilan M.; Wolpert, David H.

    2004-01-01

    Airline fleet assignment involves the allocation of aircraft to a set of flights legs in order to meet passenger demand, while satisfying a variety of constraints. Over the course of the day, the routing of each aircraft is determined in order to minimize the number of required flights for a given fleet. The associated flow continuity and aircraft count constraints have led researchers to focus on obtaining quasi-optimal solutions, especially at larger scales. In this paper, the authors propose the application of an agent-based integer optimization algorithm to a "cold start" fleet assignment problem. Results show that the optimizer can successfully solve such highly- constrained problems (129 variables, 184 constraints).

  3. Involvement of family members in life with type 2 diabetes: Six interconnected problem domains of significance for family health identity and healthcare authenticity

    PubMed Central

    Grabowski, Dan; Andersen, Tue Helms; Varming, Annemarie; Ommundsen, Christine; Willaing, Ingrid

    2017-01-01

    Objectives: Family involvement plays a key role in diabetes management. Problems and challenges related to type 2-diabetes often affect the whole family, and relatives are at increased risk of developing diabetes themselves. We highlight these issues in our objectives: (1) to uncover specific family problems associated with mutual involvement in life with type 2-diabetes and (2) to analytically look at ways of approaching these problems in healthcare settings. Methods: Qualitative data were gathered in participatory problem assessment workshops. The data were analysed in three rounds using radical hermeneutics. Results: Problems were categorized in six domains: knowledge, communication, support, everyday life, roles and worries. The final cross-analysis focusing on the link between family identity and healthcare authenticity provided information on how the six domains can be approached in healthcare settings. Conclusion: The study generated important knowledge about problems associated with family involvement in life with type 2 diabetes and about how family involvement can be supported in healthcare practice. PMID:28839943

  4. Perceptions and characteristics of registered nurses' involvement in decision making.

    PubMed

    Mangold, Kara L; Pearson, Kristina K; Schmitz, Julie R; Scherb, Cindy A; Specht, Janet P; Loes, Jean L

    2006-01-01

    This study aimed to determine the level of actual and preferred decisional involvement and ascertain whether there is decisional dissonance among registered nurses (RNs). A convenience sample of 196 RNs completed a demographic form and the Decisional Involvement Scale, a tool that measures actual and preferred decisional involvement for RNs in 6 categories: unit staffing, quality of professional practice, professional recruitment, unit governance and leadership, quality of support staff practice, and collaboration/liaison activities. From these data, the level of and difference between RN's actual and preferred decisional involvement was analyzed. In addition, the impact of level of education, years of experience, hours worked per pay period, and work setting on actual and preferred decisional involvement were measured. A statistically significant difference was found between RNs' actual and preferred decisional involvement, with RNs preferring more decisional involvement than they actually experienced. Work setting was the only variable to which a difference could be attributed. Further study is warranted to find causes of decisional dissonance and interventions that could help alleviate the problem and potentially increase job satisfaction.

  5. Prevalence of Adolescent Problem Gambling: A Systematic Review of Recent Research.

    PubMed

    Calado, Filipa; Alexandre, Joana; Griffiths, Mark D

    2017-06-01

    Previous research has shown that gambling is a popular activity among adolescents. Following a rapid expansion of legalized gambling opportunities and the emergence of new forms of gambling, many researchers have carried out studies on adolescent gambling and problem gambling. The present paper reviews studies that have been conducted worldwide since 2000, and then presents a more detailed picture of adolescent gambling research in Europe, by providing a country-by country analysis. After an extensive search on academic databases and following an exclusion process, 44 studies were identified. The findings showed that 0.2-12.3 % of youth meet criteria for problem gambling, notwithstanding differences among assessment instruments, cut-offs, and timeframes. However, despite this variability, several demographic characteristics were associated with adolescent gambling involvement and problem gambling. It is concluded that a small but significant minority of adolescents have gambling-related problems. Such findings will hopefully encourage more research into youth gambling to further understand the determinants of this phenomenon.

  6. Perturbation solutions of combustion instability problems

    NASA Technical Reports Server (NTRS)

    Googerdy, A.; Peddieson, J., Jr.; Ventrice, M.

    1979-01-01

    A method involving approximate modal analysis using the Galerkin method followed by an approximate solution of the resulting modal-amplitude equations by the two-variable perturbation method (method of multiple scales) is applied to two problems of pressure-sensitive nonlinear combustion instability in liquid-fuel rocket motors. One problem exhibits self-coupled instability while the other exhibits mode-coupled instability. In both cases it is possible to carry out the entire linear stability analysis and significant portions of the nonlinear stability analysis in closed form. In the problem of self-coupled instability the nonlinear stability boundary and approximate forms of the limit-cycle amplitudes and growth and decay rates are determined in closed form while the exact limit-cycle amplitudes and growth and decay rates are found numerically. In the problem of mode-coupled instability the limit-cycle amplitudes are found in closed form while the growth and decay rates are found numerically. The behavior of the solutions found by the perturbation method are in agreement with solutions obtained using complex numerical methods.

  7. Examining Middle School Pre-Service Teachers' Knowledge of Fraction Division Interpretations

    ERIC Educational Resources Information Center

    Alenazi, Ali

    2016-01-01

    This study investigated 11 pre-service middle school teachers' solution strategies for exploring their knowledge of fraction division interpretations. Each participant solved six fraction division problems. The problems were organized into two sets: symbolic problems (involving numbers only) and contextual problems (involving measurement…

  8. Present status of computational tools for maglev development

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

    Wang, Z.; Chen, S.S.; Rote, D.M.

    1991-10-01

    High-speed vehicles that employ magnetic levitation (maglev) have received great attention worldwide as a means of relieving both highway and air-traffic congestion. At this time, Japan and Germany are leading the development of maglev. After fifteen years of inactivity that is attributed to technical policy decisions, the federal government of the United States has reconsidered the possibility of using maglev in the United States. The National Maglev Initiative (NMI) was established in May 1990 to assess the potential of maglev in the United States. One of the tasks of the NMI, which is also the objective of this report, ismore » to determine the status of existing computer software that can be applied to maglev-related problems. The computational problems involved in maglev assessment, research, and development can be classified into two categories: electromagnetic and mechanical. Because most maglev problems are complicated and difficult to solve analytically, proper numerical methods are needed to find solutions. To determine the status of maglev-related software, developers and users of computer codes were surveyed. The results of the survey are described in this report. 25 refs.« less

  9. Detection of medication-related problems in hospital practice: a review

    PubMed Central

    Manias, Elizabeth

    2013-01-01

    This review examines the effectiveness of detection methods in terms of their ability to identify and accurately determine medication-related problems in hospitals. A search was conducted of databases from inception to June 2012. The following keywords were used in combination: medication error or adverse drug event or adverse drug reaction, comparison, detection, hospital and method. Seven detection methods were considered: chart review, claims data review, computer monitoring, direct care observation, interviews, prospective data collection and incident reporting. Forty relevant studies were located. Detection methods that were better able to identify medication-related problems compared with other methods tested in the same study included chart review, computer monitoring, direct care observation and prospective data collection. However, only small numbers of studies were involved in comparisons with direct care observation (n = 5) and prospective data collection (n = 6). There was little focus on detecting medication-related problems during various stages of the medication process, and comparisons associated with the seriousness of medication-related problems were examined in 19 studies. Only 17 studies involved appropriate comparisons with a gold standard, which provided details about sensitivities and specificities. In view of the relatively low identification of medication-related problems with incident reporting, use of this method in tracking trends over time should be met with some scepticism. Greater attention should be placed on combining methods, such as chart review and computer monitoring in examining trends. More research is needed on the use of claims data, direct care observation, interviews and prospective data collection as detection methods. PMID:23194349

  10. Dysphagia, malnutrition and gastrointestinal problems in patients with mitochondrial disease caused by the m3243A>G mutation.

    PubMed

    de Laat, P; Zweers, H E E; Knuijt, S; Smeitink, J A M; Wanten, G J A; Janssen, M C H

    2015-01-01

    Previous research has shown that dysphagia and gastrointestinal problems occur frequently in carriers of the m.3243A>G mutation; however, the exact frequency and severity have not been determined. We hypothesise that adult carriers have an increased risk for malnutrition. In this observational study we evaluated the presence of gastrointestinal problems and dysphagia in 92 carriers of the m.3243A>G mutation. The severity of the general disease involvement was classified using the Newcastle Mitochondrial Disease Adult Scale (NMDAS). Gastrointestinal involvement, dysphagia and the risk for malnutrition were scored using the Gastrointestinal Symptoms Questionnaire and the Malnutrition Universal Screening Tool. Gastrointestinal symptoms and anthropometrics were compared with healthy controls. Our results show that the height, weight and body mass index (BMI) of these carriers were lower than the national average (p < 0.05). Seventy-nine carriers (86%) suffered from at least one gastrointestinal symptom, mainly flatulence or hard stools. Both frequency and severity of symptoms were significantly increased compared with reference data of healthy Dutch adults. Of the carriers, 45% reported (mostly mild) dysphagia. Solid foods cause more problems than liquids. A negative correlation between BMI and heteroplasmy levels in urinary epithelial cells (UEC) was present (Spearman correlation coefficient = - 0.319, p = 0.003). Dysphagia and gastrointestinal problems, especially constipation, are common symptoms in the total m.3243A>G carriers cohort and are not related to heteroplasmy levels in UEC or disease severity. The severity of gastrointestinal problems as well as overall disease severity is associated with an increased risk for malnutrition.

  11. Planning continuing training.

    PubMed

    Nacef, T; Argellies, J L

    1982-01-01

    Suggests new direction in the approach to planning continued training of medical personnel. Under this new scheme, health problems themselves will be the sole basis for the planning of the continuing training program. This approach assures the involvement of health professionals at various levels and fosters a multiprofessional involvement in continuing training. It is also recommended that the preventive aspects of medicine be stressed far more than is typical of traditional hospital services. The method for decision making in program planning includes 6 steps: 1) choice of health problem to be solved (includes considerations of severity of the problems and the degree to which continuing training will be of value); 2) analysis of the number and type of health personnel needed; 3) determination of desired skill acquisition; 4) analysis of teaching/educational requirements; 5) inventory of resources (time, facilities, staff, instructional materials) available; 6) evaluation. Coordination at different levels, both national and regional, ensures the cohesion of the multiprofessional continuing training system. Regional cell groups, composed of 2 paramedicals and a doctor administer continuing training sessions under policy established at a national level by a national advisory committee. This approach makes continuing training an important and immediate component of health policy aimed at delivering basic health services to the entire population.

  12. Zeroth Law, Entropy, Equilibrium, and All That

    NASA Astrophysics Data System (ADS)

    Canagaratna, Sebastian G.

    2008-05-01

    The place of the zeroth law in the teaching of thermodynamics is examined in the context of the recent discussion by Gislason and Craig of some problems involving the establishment of thermal equilibrium. The concept of thermal equilibrium is introduced through the zeroth law. The relation between the zeroth law and the second law in the traditional approach to thermodynamics is discussed. It is shown that the traditional approach does not need to appeal to the second law to solve with rigor the type of problems discussed by Gislason and Craig: in problems not involving chemical reaction, the zeroth law and the condition for mechanical equilibrium, complemented by the first law and any necessary equations of state, are sufficient to determine the final state. We have to invoke the second law only if we wish to calculate the change of entropy. Since most students are exposed to a traditional approach to thermodynamics, the examples of Gislason and Craig are re-examined in terms of the traditional formulation. The maximization of the entropy in the final state can be verified in the traditional approach quite directly by the use of the fundamental equations of thermodynamics. This approach uses relatively simple mathematics in as general a setting as possible.

  13. Application of the MERIT survey in the multi-criteria quality assessment of occupational health and safety management.

    PubMed

    Korban, Zygmunt

    2015-01-01

    Occupational health and safety management systems apply audit examinations as an integral element of these systems. The examinations are used to verify whether the undertaken actions are in compliance with the accepted regulations, whether they are implemented in a suitable way and whether they are effective. One of the earliest solutions of that type applied in the mining industry in Poland involved the application of audit research based on the MERIT survey (Management Evaluation Regarding Itemized Tendencies). A mathematical model applied in the survey facilitates the determination of assessment indexes WOPi for each of the assessed problem areas, which, among other things, can be used to set up problem area rankings and to determine an aggregate (synthetic) assessment. In the paper presented here, the assessment indexes WOPi were used to calculate a development measure, and the calculation process itself was supplemented with sensitivity analysis.

  14. Understanding Dali's Slave market with the disappearing bust of Voltaire: a case study in the scale information driving perception.

    PubMed

    Bonnar, Lizann; Gosselin, Frédéric; Schyns, Philippe G

    2002-01-01

    A generic problem in vision is to know which information drives the perception of a stimulus. We address this problem in a case study that involves the perceptual reversal of an ambiguous image (here, Dali's painting the Slave Market with the Disappearing Bust of Voltaire 1940). In experiment 1, we use 'bubbles' (Gosselin and Schyns, 2001 Vision Research 41 2261-2271) to disambiguate the image and to determine the specific visual information that drives each possible perception (here, the nuns versus the bust of Voltaire). Experiment 2 validates that this information does determine the selective perception of the ambiguous image. We adapted the spatial-frequency channels of observers selectively to the information that mediates one of the two perceptions, to induce the opposite perception of the ambiguous image in a transfer phase. Together, the results suggest a method of revealing the visual information that drives perception.

  15. Optimal timing in biological processes

    USGS Publications Warehouse

    Williams, B.K.; Nichols, J.D.

    1984-01-01

    A general approach for obtaining solutions to a class of biological optimization problems is provided. The general problem is one of determining the appropriate time to take some action, when the action can be taken only once during some finite time frame. The approach can also be extended to cover a number of other problems involving animal choice (e.g., mate selection, habitat selection). Returns (assumed to index fitness) are treated as random variables with time-specific distributions, and can be either observable or unobservable at the time action is taken. In the case of unobservable returns, the organism is assumed to base decisions on some ancillary variable that is associated with returns. Optimal policies are derived for both situations and their properties are discussed. Various extensions are also considered, including objective functions based on functions of returns other than the mean, nonmonotonic relationships between the observable variable and returns; possible death of the organism before action is taken; and discounting of future returns. A general feature of the optimal solutions for many of these problems is that an organism should be very selective (i.e., should act only when returns or expected returns are relatively high) at the beginning of the time frame and should become less and less selective as time progresses. An example of the application of optimal timing to a problem involving the timing of bird migration is discussed, and a number of other examples for which the approach is applicable are described.

  16. A Semi-Infinite Programming based algorithm for determining T-optimum designs for model discrimination

    PubMed Central

    Duarte, Belmiro P.M.; Wong, Weng Kee; Atkinson, Anthony C.

    2016-01-01

    T-optimum designs for model discrimination are notoriously difficult to find because of the computational difficulty involved in solving an optimization problem that involves two layers of optimization. Only a handful of analytical T-optimal designs are available for the simplest problems; the rest in the literature are found using specialized numerical procedures for a specific problem. We propose a potentially more systematic and general way for finding T-optimal designs using a Semi-Infinite Programming (SIP) approach. The strategy requires that we first reformulate the original minimax or maximin optimization problem into an equivalent semi-infinite program and solve it using an exchange-based method where lower and upper bounds produced by solving the outer and the inner programs, are iterated to convergence. A global Nonlinear Programming (NLP) solver is used to handle the subproblems, thus finding the optimal design and the least favorable parametric configuration that minimizes the residual sum of squares from the alternative or test models. We also use a nonlinear program to check the global optimality of the SIP-generated design and automate the construction of globally optimal designs. The algorithm is successfully used to produce results that coincide with several T-optimal designs reported in the literature for various types of model discrimination problems with normally distributed errors. However, our method is more general, merely requiring that the parameters of the model be estimated by a numerical optimization. PMID:27330230

  17. A Semi-Infinite Programming based algorithm for determining T-optimum designs for model discrimination.

    PubMed

    Duarte, Belmiro P M; Wong, Weng Kee; Atkinson, Anthony C

    2015-03-01

    T-optimum designs for model discrimination are notoriously difficult to find because of the computational difficulty involved in solving an optimization problem that involves two layers of optimization. Only a handful of analytical T-optimal designs are available for the simplest problems; the rest in the literature are found using specialized numerical procedures for a specific problem. We propose a potentially more systematic and general way for finding T-optimal designs using a Semi-Infinite Programming (SIP) approach. The strategy requires that we first reformulate the original minimax or maximin optimization problem into an equivalent semi-infinite program and solve it using an exchange-based method where lower and upper bounds produced by solving the outer and the inner programs, are iterated to convergence. A global Nonlinear Programming (NLP) solver is used to handle the subproblems, thus finding the optimal design and the least favorable parametric configuration that minimizes the residual sum of squares from the alternative or test models. We also use a nonlinear program to check the global optimality of the SIP-generated design and automate the construction of globally optimal designs. The algorithm is successfully used to produce results that coincide with several T-optimal designs reported in the literature for various types of model discrimination problems with normally distributed errors. However, our method is more general, merely requiring that the parameters of the model be estimated by a numerical optimization.

  18. Wither the Concepts of Mole and Concentration: Conceptual Confusion in Applying M[subscript 1]v[subscript 1] = M[subscript 2]v[subscript 2

    ERIC Educational Resources Information Center

    Chong, Sheau Huey

    2016-01-01

    Concentration of solutions problems are among the most important and at the same time one of the most challenging topics in chemistry. The aim of this study was to determine the sources of the difficulty that students often face when performing calculations related to concentration. The study involved 153 tertiary college students (food science,…

  19. STUDIES IN WORKMEN'S COMPENSATION AND RADIATION INJURY. VOLUME II, THE INCIDENCE, NATURE AND ADJUDICATION OF WORKMEN'S COMPENSATION CLAIMS INVOLVING RADIATION EXPOSURE AND DELAYED INJURY.

    ERIC Educational Resources Information Center

    O'TOOLE, THOMAS J.

    THE PURPOSE OF THE STUDY WAS TO PROVIDE A FACTUAL BACKGROUND AGAINST WHICH JUDGMENTS CAN BE MADE CONCERNING THE MAGNITUDE OF THE PROBLEM OF INJURY APPEARING SOME TIME AFTER THE EXPOSURE TO IONIZING RADIATION AND DETERMINE WHETHER EXISTING LAWS PERMIT A JUST AND EQUITABLE ADJUDICATION OF RADIATION COMPENSATION CLAIMS. THE STUDY WAS BASED UPON THE…

  20. Pizza Boy vs the Highway Department

    NASA Astrophysics Data System (ADS)

    Ilyes, Mark A.; Filizzi, James M.

    2005-10-01

    Many physics teachers and physics education researchers have found that students are highly motivated by classroom or laboratory experiences involving practical, "real-life" scenarios. Rather than attempting to verify a known relationship, they are asked to use an existing relationship to solve some practical problem. The purpose of this experimental investigation is to determine the speed of a car prior to applying the brakes and skidding into a flatbed tractor-trailer.

  1. Calculation Software

    NASA Technical Reports Server (NTRS)

    1994-01-01

    MathSoft Plus 5.0 is a calculation software package for electrical engineers and computer scientists who need advanced math functionality. It incorporates SmartMath, an expert system that determines a strategy for solving difficult mathematical problems. SmartMath was the result of the integration into Mathcad of CLIPS, a NASA-developed shell for creating expert systems. By using CLIPS, MathSoft, Inc. was able to save the time and money involved in writing the original program.

  2. Controlled ecological life support system higher plant flight experiments

    NASA Technical Reports Server (NTRS)

    Tibbitts, T. W.; Wheeler, R. M.

    1984-01-01

    Requirements for spaceflight experments which involve higher plants were determined. The plants are studied for use in controlled ecological life support systems (CELSS). Two categories of research requirements are discussed: (1) the physical needs which include nutrient, water and gas exchange requirements; (2) the biological and physiological functions which affect plants in zero gravity environments. Physical problems studies are given the priority since they affect all biological experiments.

  3. The virtual windtunnel: Visualizing modern CFD datasets with a virtual environment

    NASA Technical Reports Server (NTRS)

    Bryson, Steve

    1993-01-01

    This paper describes work in progress on a virtual environment designed for the visualization of pre-computed fluid flows. The overall problems involved in the visualization of fluid flow are summarized, including computational, data management, and interface issues. Requirements for a flow visualization are summarized. Many aspects of the implementation of the virtual windtunnel were uniquely determined by these requirements. The user interface is described in detail.

  4. Institutional analysis of milkfish supply chain using interpretive structural modelling (ISM) (case study of UD. Bunda Foods, Sidoarjo District)

    NASA Astrophysics Data System (ADS)

    Silalahi, R. L. R.; Mustaniroh, S. A.; Ikasari, D. M.; Sriulina, R. P.

    2018-03-01

    UD. Bunda Foods is an SME located in the district of Sidoarjo. UD. Bunda Foods has problems of maintaining its milkfish’s quality assurance and developing marketing strategies. Improving those problems enables UD. Bunda Foods to compete with other similar SMEs and to market its product for further expansion of their business. The objectives of this study were to determine the model of the institutional structure of the milkfish supply chain, to determine the elements, the sub-elements, and the relationship among each element. The method used in this research was Interpretive Structural Modeling (ISM), involving 5 experts as respondents consisting of 1 practitioner, 1 academician, and 3 government organisation employees. The results showed that there were two key elements include requirement and goals elements. Based on the Drive Power-Dependence (DP-D) matrix, the key sub-elements of requirement element, consisted of raw material continuity, appropriate marketing strategy, and production capital, were positioned in the Linkage sector quadrant. The DP-D matrix for the key sub-elements of the goal element also showed a similar position. The findings suggested several managerial implications to be carried out by UD. Bunda Foods include establishing good relationships with all involved institutions, obtaining capital assistance, and attending the marketing training provided by the government.

  5. The intergenerational transmission of at-risk/problem gambling: The moderating role of parenting practices.

    PubMed

    Dowling, Nicki A; Shandley, Kerrie A; Oldenhof, Erin; Affleck, Julia M; Youssef, George J; Frydenberg, Erica; Thomas, Shane A; Jackson, Alun C

    2017-10-01

    Although parenting practices are articulated as underlying mechanisms or protective factors in several theoretical models, their role in the intergenerational transmission of gambling problems has received limited research attention. This study therefore examined the degree to which parenting practices (positive parenting, parental involvement, and inconsistent discipline) moderated the intergenerational transmission of paternal and maternal problem gambling. Students aged 12-18 years (N = 612) recruited from 17 Australian secondary schools completed a survey measuring parental problem gambling, problem gambling severity, and parenting practices. Participants endorsing paternal problem gambling (23.3%) were 4.3 times more likely to be classified as at-risk/problem gamblers than their peers (5.4%). Participants endorsing maternal problem gambling (6.9%) were no more likely than their peers (4.0%) to be classified as at-risk/problem gamblers. Paternal problem gambling was a significant predictor of offspring at-risk/problem gambling after controlling for maternal problem gambling and participant demographic characteristics. The relationship between maternal problem gambling and offspring at-risk/problem gambling was buffered by parental involvement. Paternal problem gambling may be important in the development of adolescent at-risk/problem gambling behaviours and higher levels of parental involvement buffers the influence of maternal problem gambling in the development of offspring gambling problems. Further research is therefore required to identify factors that attenuate the seemingly greater risk of transmission associated with paternal gambling problems. Parental involvement is a potential candidate for prevention and intervention efforts designed to reduce the intergenerational transmission of gambling problems. (Am J Addict 2017;26:707-712). © 2017 American Academy of Addiction Psychiatry.

  6. Single-tier city logistics model for single product

    NASA Astrophysics Data System (ADS)

    Saragih, N. I.; Nur Bahagia, S.; Suprayogi; Syabri, I.

    2017-11-01

    This research develops single-tier city logistics model which consists of suppliers, UCCs, and retailers. The problem that will be answered in this research is how to determine the location of UCCs, to allocate retailers to opened UCCs, to assign suppliers to opened UCCs, to control inventory in the three entities involved, and to determine the route of the vehicles from opened UCCs to retailers. This model has never been developed before. All the decisions will be simultaneously optimized. Characteristic of the demand is probabilistic following a normal distribution, and the number of product is single.

  7. Maternal Depressive Symptoms and Child Behavior Problems among Latina Adolescent Mothers: The Buffering Effect of Mother-reported Partner Child Care Involvement

    PubMed Central

    Smith, Erin N.; Grau, Josefina M.; Duran, Petra A.; Castellanos, Patricia

    2013-01-01

    We examined the relations between maternal depressive symptoms and child internalizing and externalizing problems in a sample of 125 adolescent Latina mothers (primarily Puerto Rican) and their toddlers. We also tested the influence of mother-reported partner child care involvement on child behavior problems and explored mother-reported partner characteristics that related to this involvement. Results suggested that maternal depressive symptoms related to child internalizing and externalizing problems when accounting for contextual risk factors. Importantly, these symptoms mediated the link between life stress and child behavior problems. Mother-reported partner child care interacted with maternal depressive symptoms for internalizing, not externalizing, problems. Specifically, depressive symptoms related less strongly to internalizing problems at higher levels of partner child care than at lower levels. Participants with younger partners, co-residing partners, and in longer romantic relationships reported higher partner child care involvement. Results are discussed considering implications for future research and interventions for mothers, their children, and their partners. PMID:24339474

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

    Sanger, P.; Adam, E.; Grabinsky, G.

    A conductor using flowing supercritical helium as a coolant has been adopted for the superconducting magnet being built by the Airco-Westinghouse team for the LCP at Oak Ridge National Laboratory. This conductor utilizes the ''rope in a pipe'' concept in which a large number of superconductor Nb/sub 3/Sn strands are formed into a cable and wrapped in a stainless steel jacket. The jacket material and conductor processing are given; the sequence of forming stages involved in producing the jacket is illustrated. It is found that the adoption of the iron-based superalloy JBK-75 as the jacket material revealed problems significantly differentmore » from those of the 304L and 21-6-9 stainless steel jackets. These problems included poor abrasion behavior, different reactions to cold reduction, and the presence of aluminum and titanium oxide floaters on the welds. The research underscores the fact that many material properties involved in proper selection are not well understood a priori and can only be determined by trial and error.« less

  9. The determination factors of left-right asymmetry disorders- a short review.

    PubMed

    Catana, Andreea; Apostu, Adina Patricia

    2017-01-01

    Laterality defects in humans, situs inversus and heterotaxy, are rare disorders, with an incidence of 1:8000 to 1:10 000 in the general population, and a multifactorial etiology. It has been proved that 1.44/10 000 of all cardiac problems are associated with malformations of left-right asymmetry and heterotaxy accounts for 3% of all congenital heart defects. It is considered that defects of situs appear due to genetic and environmental factors. Also, there is evidence that the ciliopathies (defects of structure or function) are involved in development abnormalities. Over 100 genes have been reported to be involved in left-right patterning in model organisms, but only a few are likely to candidate for left-right asymmetry defects in humans. Left-right asymmetry disorders are genetically heterogeneous and have variable manifestations (from asymptomatic to serious clinical problems). The discovery of the right mechanism of left-right development will help explain the clinical complexity and may contribute to a therapy of these disorders.

  10. Forces on a current-carrying wire in a magnetic field: the macro-micro connection

    NASA Astrophysics Data System (ADS)

    Karam, R.; Kneubil, F. B.; Robilotta, M. R.

    2017-09-01

    The classic problem of determining the force on a current-carrying wire in a magnetic field is critically analysed. A common explanation found in many introductory textbooks is to represent the force on the wire as the sum of the forces on charge carriers. In this approach neither the nature of the forces involved nor their application points are fully discussed. In this paper we provide an alternative microscopic explanation that is suitable for introductory electromagnetism courses at university level. By considering the wire as a superposition of a positive and a negative cylindrical charge distributions, we show that the electrons are subject to both magnetic and electric forces, whereas the ionic lattice of the metal is dragged by an electric force. Furthermore, an analysis of the orders of magnitude involved in the problem gives counterintuitive results with valuable educational potential. We argue that this approach allows one to discuss different aspects of the physical knowledge, which are relevant in physics education.

  11. Investigating a hybrid perturbation-Galerkin technique using computer algebra

    NASA Technical Reports Server (NTRS)

    Andersen, Carl M.; Geer, James F.

    1988-01-01

    A two-step hybrid perturbation-Galerkin method is presented for the solution of a variety of differential equations type problems which involve a scalar parameter. The resulting (approximate) solution has the form of a sum where each term consists of the product of two functions. The first function is a function of the independent field variable(s) x, and the second is a function of the parameter lambda. In step one the functions of x are determined by forming a perturbation expansion in lambda. In step two the functions of lambda are determined through the use of the classical Bubnov-Gelerkin method. The resulting hybrid method has the potential of overcoming some of the drawbacks of the perturbation and Bubnov-Galerkin methods applied separately, while combining some of the good features of each. In particular, the results can be useful well beyond the radius of convergence associated with the perturbation expansion. The hybrid method is applied with the aid of computer algebra to a simple two-point boundary value problem where the radius of convergence is finite and to a quantum eigenvalue problem where the radius of convergence is zero. For both problems the hybrid method apparently converges for an infinite range of the parameter lambda. The results obtained from the hybrid method are compared with approximate solutions obtained by other methods, and the applicability of the hybrid method to broader problem areas is discussed.

  12. Multisensory visual servoing by a neural network.

    PubMed

    Wei, G Q; Hirzinger, G

    1999-01-01

    Conventional computer vision methods for determining a robot's end-effector motion based on sensory data needs sensor calibration (e.g., camera calibration) and sensor-to-hand calibration (e.g., hand-eye calibration). This involves many computations and even some difficulties, especially when different kinds of sensors are involved. In this correspondence, we present a neural network approach to the motion determination problem without any calibration. Two kinds of sensory data, namely, camera images and laser range data, are used as the input to a multilayer feedforward network to associate the direct transformation from the sensory data to the required motions. This provides a practical sensor fusion method. Using a recursive motion strategy and in terms of a network correction, we relax the requirement for the exactness of the learned transformation. Another important feature of our work is that the goal position can be changed without having to do network retraining. Experimental results show the effectiveness of our method.

  13. Factors associated with early marijuana initiation in a criminal justice population.

    PubMed

    Savage, Rebekah J; King, Vinetra L; Clark, C Brendan; Cropsey, Karen L

    2017-01-01

    Initiation of marijuana during adolescence is associated with negative outcomes and is more common among those with criminal justice involvement. We sought to determine demographics, psychosocial factors, mental health factors, and criminal outcomes associated with earlier age at first marijuana use in a criminal justice population. Data from structured, in-person interviews of adults in a criminal corrections program were analyzed. Participants (689 men and women ages 19 and older) were recruited for a larger smoking cessation trial (2009-2013) as a volunteer sample by flyers at a community corrections site. 516 had smoked both nicotine and marijuana and were included in the analysis. We determined associations between self-reported age at first marijuana use and sex, race, income, educational attainment, history of abuse, family problems, psychiatric problems, criminal record, and age of nicotine and alcohol initiation. Of 516 participants, 68% were men, and 64.5% were Black. No participants were of Hispanic ethnicity. Average age of marijuana initiation was 15.1years (SD 3.7years). After linear regression, earlier age at marijuana initiation was associated with male sex and more criminal offenses (person/violent and court). Race and psychiatric problems were not associated with earlier marijuana initiation. Earlier adolescent marijuana initiation is associated with more criminal offenses in a criminal justice population. Men initiate marijuana earlier than women. Adolescents at high risk of justice involvement may benefit from delayed initiation of marijuana, specifically men. Additional studies should examine prevention strategies for adolescent marijuana use that target those at highest risk. Copyright © 2016. Published by Elsevier Ltd.

  14. The determinants of the antibiotic resistance process

    PubMed Central

    Franco, Beatriz Espinosa; Altagracia Martínez, Marina; Sánchez Rodríguez, Martha A; Wertheimer, Albert I

    2009-01-01

    Background: The use of antibiotic drugs triggers a complex interaction involving many biological, sociological, and psychological determinants. Resistance to antibiotics is a serious worldwide problem which is increasing and has implications for morbidity, mortality, and health care both in hospitals and in the community. Objectives: To analyze current research on the determinants of antibiotic resistance and comprehensively review the main factors in the process of resistance in order to aid our understanding and assessment of this problem. Methods: We conducted a MedLine search using the key words “determinants”, “antibiotic”, and “antibiotic resistance” to identify publications between 1995 and 2007 on the determinants of antibiotic resistance. Publications that did not address the determinants of antibiotic resistance were excluded. Results: The process and determinants of antibiotic resistance are described, beginning with the development of antibiotics, resistance and the mechanisms of resistance, sociocultural determinants of resistance, the consequences of antibiotic resistance, and alternative measures proposed to combat antibiotic resistance. Conclusions: Analysis of the published literature identified the main determinants of antibiotic resistance as irrational use of antibiotics in humans and animal species, insufficient patient education when antibiotics are prescribed, lack of guidelines for treatment and control of infections, lack of scientific information for physicians on the rational use of antibiotics, and lack of official government policy on the rational use of antibiotics in public and private hospitals. PMID:21694883

  15. Behavioral correlation with television watching and videogame playing among children in the United Arab Emirates.

    PubMed

    Yousef, Said; Eapen, Valsamma; Zoubeidi, Taoufik; Mabrouk, Abdelazim

    2014-08-01

    Television viewing and videogame use (TV/VG) appear to be associated with some childhood behavioral problems. There are no studies addressing this problem in the United Arab Emirates. One hundred ninety-seven school children (mean age, 8.7 ± 2.1 years) were assessed. Child Behavior Checklist (CBCL) subscale scores and socio-demographic characteristics were compared between children who were involved with TV/VG more than 2 hours/day and those involved less than 2 hours/day (the recommended upper limit by The American Academy of Pediatrics). Thirty-seven percent of children who were involved with TV/VG time of more than 2 hours/day scored significantly higher on CBCL syndrome scales of withdrawn, social problems, attention problems, delinquent behavior, aggressive behavior, internalizing problems, externalizing problems and the CBCL total scores compared with their counterparts. Moreover, these children were younger in birth order and had fewer siblings. After controlling for these confounders using logistic regression, we found that TV/VG time more than 2 hours/day was positively associated with withdrawn (p = 0.008), attention problem (p = 0.037), externalizing problems (p = 0.007), and CBCL total (p = 0.014). Involvement with TV/VG for more than 2 hours/day is associated with more childhood behavioral problems. Counteracting negative effects of the over-involvement with TV/VG in children requires increased parental awareness.

  16. Counterfeit medicines in Peru: a retrospective review (1997-2014).

    PubMed

    Medina, Edwin; Bel, Elvira; Suñé, Josep María

    2016-04-04

    To consolidate and assess information on counterfeit medicines subject to pharmaceutical alerts issued by the Peruvian Medicines Regulatory Authority over 18 years (1997-2014) of health monitoring and enforcement. A retrospective review of drug alerts. A search of the website of the General Directorate of Medicines, Supplies and Drugs (DIGEMID) of the Ministry of Health of Peru for drug alerts issued between 1997 and 2014. Drug alerts related to counterfeit medicines. A total of 669 DIGEMID alerts were issued during the study period, 354 (52.91%) of which cover 1738 cases of counterfeit medicines (many alerts deal with several cases at a time). 1010 cases (58.11%) involved pharmaceutical establishments and 349 (20.08%) involved non-pharmaceutical commercial outlets. In 126 cases (7.25%), counterfeit medicines were seized in an unauthorised trade (without any marketing authorisation); in 253 cases (14.56%) the type of establishment or business associated with the seized product was not identified. Counterfeit medicines are a serious public health problem in Peru. A review of the data cannot determine whether counterfeit medicines in Peru increased during the study period, or if monitoring by different government health agencies highlighted the magnitude of the problem by providing more evidence. The problem is clearly structural, since the majority of cases (58.11% of the total) were detected in legitimate supply chains. Most counterfeit medicines involve staple pharmaceutical products and common dosage forms. Considerable work remains to be done to control the serious problem of counterfeit medicines in Peru. 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/

  17. Adverse Childhood Experiences, Coping Resources, and Mental Health Problems among Court-Involved Youth

    ERIC Educational Resources Information Center

    Logan-Greene, Patricia; Tennyson, Robert L.; Nurius, Paula S.; Borja, Sharon

    2017-01-01

    Background: Mental health problems are gaining attention among court-involved youth with emphasis on the role of childhood adversity, but assessment lags. Objective: The present study uses a commonly delivered assessment tool to examine mental health problems (current mental health problem, mental health interfered with probation goals, and…

  18. Cognitive constraints on high school students' representations of real environmental problems

    NASA Astrophysics Data System (ADS)

    Barnes, Ervin Kenneth

    One class of juniors and seniors was studied through one semester in the investigation of how students think about, learn from, and solve real environmental problems. The intention was to listen to student voices while researching the features of their representations of these problems, the beliefs they held (tenets), the cognitive processes they employed, and the principles of science, ecology, problem solving, and ethics they held as tenets. The focus was upon two self-selected groups as they perceived, engaged, analyzed, and proposed solutions for problems. Analysis of the student representations involved interpretation of the features to include both the perspective tenets and the envisioning processes. These processes included the intentive and attentive constraints as tenet acquisition and volitive and agential constraints as tenet affirmation. The perspective tenets included a variety of conceptual (basic science, ecological, ethical, and problem-solving) constraints as well as ontological, epistemological, and other cultural (role, status, power, and community) constraints. The perspective tenets were interpreted thematically including the ways populations of people cause and care about environmental problems, the magnitude of environmental problems and the science involved, the expectations and limitations students perceive for themselves, and the importance of community awareness and cooperation to addressing these problems. Some of these tenets were interpreted to be principles in that they were rules that were accepted by some people as true. The perspective tenets, along with the envisioning processes, were perceived to be the constraints that determined the environmental problems and limited the solution possibilities. The students thought about environmental problems in mature and principled ways using a repertoire of cognitive processes. They learned from them as they acquired and affirmed tenets. They solved them through personal choices and efforts to increase community awareness. The ways students think about, learn from, and solve real environmental problems were all constrained by the perspective tenets (including cultural tenets of role, status, and power) and envisioning processes. It was concluded that students need help from the community to go further in solving these real environmental problems.

  19. Fatigue is correlated with disease activity but not with the type of organ involvement in Behçet's syndrome: a comparative clinical survey.

    PubMed

    Buyuktas, Deram; Hatemi, Gulen; Yuksel-Findikoglu, Sukran; Ugurlu, Serdal; Yazici, Hasan; Yurdakul, Sebahattin

    2015-01-01

    Fatigue is an important problem in inflammatory diseases and affects the quality of life (QoL). We aimed to evaluate the severity and impact of fatigue in Behçet's syndrome (BS) and to determine its association with type of organ involvement and gender. One hundred and fifty-two BS, 51 rheumatoid arthritis (RA), 51 systemic lupus erythematosus (SLE), 51 ankylosing spondylitis (AS) patients and 65 healthy controls were evaluated by the fatigue severity scale, fatigue impact scale, fibromyalgia impact questionnaire (FIQ), RAPID3, SF-36 and Behçet's syndrome activity scale (the latter only in BS patients). We also analysed subgroups of BS patients with predominantly eye, vascular, joint and mucocutaneous involvement and did an additional gender analysis. Fatigue severity and fatigue impact scores were similar among BS, RA, SLE and AS patients and significantly higher than that in healthy controls (F4df=8.51; p<0.001 and F4df=8.67; p<0.001, respectively). The fatigue severity and fatigue impact scores were similarly high in BS subgroups with different types of organ involvement, and in both genders. Fatigue is an important problem in BS, as it is in other inflammatory conditions. It is similarly severe in subgroups of patients with eye, vascular, joint and mucocutaneous involvement and in either gender. Fatigue is a candidate outcome measure for clinical trials, to assess the life impact of Behçet's syndrome.

  20. Safety of Levetiracetam in Paediatrics: A Systematic Review

    PubMed Central

    Egunsola, Oluwaseun; Choonara, Imti; Sammons, Helen Mary

    2016-01-01

    Objective To identify adverse events (AEs) associated with Levetiracetam (LEV) in children. Methods Databases EMBASE (1974-February 2015) and Medline (1946-February 2015) were searched for articles in which paediatric patients (≤18 years) received LEV treatment for epilepsy. All studies with reports on safety were included. Studies involving adults, mixed age population (i.e. children and adults) in which the paediatric subpopulation was not sufficiently described, were excluded. A meta-analysis of the RCTs was carried out and association between the commonly reported AEs or treatment discontinuation and the type of regimen (polytherapy or monotherapy) was determined using Chi2 analysis. Results Sixty seven articles involving 3,174 paediatric patients were identified. A total of 1,913 AEs were reported across studies. The most common AEs were behavioural problems and somnolence, which accounted for 10.9% and 8.4% of all AEs in prospective studies. 21 prospective studies involving 1120 children stated the number of children experiencing AEs. 47% of these children experienced AEs. Significantly more children experienced AEs with polytherapy (64%) than monotherapy (22%) (p<0.001). Levetiracetam was discontinued in 4.5% of all children on polytherapy and 0.9% on monotherapy (p<0.001), the majority were due to behavioural problems. Conclusion Behavioural problems and somnolence were the most prevalent adverse events to LEV and the most common causes of treatment discontinuation. Children on polytherapy have a greater risk of adverse events than those receiving monotherapy. PMID:26930201

  1. Progressive Elaboration and Cross-Validation of a Latent Class Typology of Adolescent Alcohol Involvement in a National Sample

    PubMed Central

    Donovan, John E.; Chung, Tammy

    2015-01-01

    Objective: Most studies of adolescent drinking focus on single alcohol use behaviors (e.g., high-volume drinking, drunkenness) and ignore the patterning of adolescents’ involvement across multiple alcohol behaviors. The present latent class analyses (LCAs) examined a procedure for empirically determining multiple cut points on the alcohol use behaviors in order to establish a typology of adolescent alcohol involvement. Method: LCA was carried out on six alcohol use behavior indicators collected from 6,504 7th through 12th graders who participated in Wave I of the National Longitudinal Study of Adolescent Health (AddHealth). To move beyond dichotomous indicators, a “progressive elaboration” strategy was used, starting with six dichotomous indicators and then evaluating a series of models testing additional cut points on the ordinal indicators at progressively higher points for one indicator at a time. Analyses were performed on one random half-sample, and confirmatory LCAs were performed on the second random half-sample and in the Wave II data. Results: The final model consisted of four latent classes (never or non–current drinkers, low-intake drinkers, non–problem drinkers, and problem drinkers). Confirmatory LCAs in the second random half-sample from Wave I and in Wave II support this four-class solution. The means on the four latent classes were also generally ordered on an array of measures reflecting psychosocial risk for problem behavior. Conclusions: These analyses suggest that there may be four different classes or types of alcohol involvement among adolescents, and, more importantly, they illustrate the utility of the progressive elaboration strategy for moving beyond dichotomous indicators in latent class models. PMID:25978828

  2. A framework for discrete stochastic simulation on 3D moving boundary domains

    DOE PAGES

    Drawert, Brian; Hellander, Stefan; Trogdon, Michael; ...

    2016-11-14

    We have developed a method for modeling spatial stochastic biochemical reactions in complex, three-dimensional, and time-dependent domains using the reaction-diffusion master equation formalism. In particular, we look to address the fully coupled problems that arise in systems biology where the shape and mechanical properties of a cell are determined by the state of the biochemistry and vice versa. To validate our method and characterize the error involved, we compare our results for a carefully constructed test problem to those of a microscale implementation. Finally, we demonstrate the effectiveness of our method by simulating a model of polarization and shmoo formationmore » during the mating of yeast. The method is generally applicable to problems in systems biology where biochemistry and mechanics are coupled, and spatial stochastic effects are critical.« less

  3. Radar image interpretation techniques applied to sea ice geophysical problems

    NASA Technical Reports Server (NTRS)

    Carsey, F. D.

    1983-01-01

    The geophysical science problems in the sea ice area which at present concern understanding the ice budget, where ice is formed, how thick it grows and where it melts, and the processes which control the interaction of air-sea and ice at the ice margins is discussed. The science problems relate to basic questions of sea ice: how much is there, thickness, drift rate, production rate, determination of the morphology of the ice margin, storms feeling for the ice, storms and influence at the margin to alter the pack, and ocean response to a storm at the margin. Some of these questions are descriptive and some require complex modeling of interactions between the ice, the ocean, the atmosphere and the radiation fields. All involve measurements of the character of the ice pack, and SAR plays a significant role in the measurements.

  4. Numerical modeling of subsurface communication, revision 1

    NASA Astrophysics Data System (ADS)

    Burke, G. J.; Dease, C. G.; Didwall, E. M.; Lytle, R. J.

    1985-08-01

    Techniques are described for numerical modeling of through-the-Earth communication. The basic problem considered is evaluation of the field at a surface or airborne station due to an antenna buried in the earth. Equations are given for the field of a point source in a homogeneous or stratified Earth. These expressions involve infinite integrals over wave number, sometimes known as Sommerfeld integrals. Numerical techniques used for evaluating these integrals are outlined. The problem of determining the current on a real antenna in the Earth, including the effect of insulation, is considered. Results are included for the fields of a point source in homogeneous and stratified earths and the field of a finite insulated dipole. The results are for electromagnetic propagation in the ELF-VLF range, but the codes also can address propagation problems at higher frequencies.

  5. Image flows and one-liner graphical image representation.

    PubMed

    Makhervaks, Vadim; Barequet, Gill; Bruckstein, Alfred

    2002-10-01

    This paper introduces a novel graphical image representation consisting of a single curve-the one-liner. The first step of the algorithm involves the detection and ranking of image edges. A new edge exploration technique is used to perform both tasks simultaneously. This process is based on image flows. It uses a gradient vector field and a new operator to explore image edges. Estimation of the derivatives of the image is performed by using local Taylor expansions in conjunction with a weighted least-squares method. This process finds all the possible image edges without any pruning, and collects information that allows the edges found to be prioritized. This enables the most important edges to be selected to form a skeleton of the representation sought. The next step connects the selected edges into one continuous curve-the one-liner. It orders the selected edges and determines the curves connecting them. These two problems are solved separately. Since the abstract graph setting of the first problem is NP-complete, we reduce it to a variant of the traveling salesman problem and compute an approximate solution to it. We solve the second problem by using Dijkstra's shortest-path algorithm. The full software implementation for the entire one-liner determination process is available.

  6. Peer rejection in childhood, involvement with antisocial peers in early adolescence, and the development of externalizing behavior problems

    PubMed Central

    Laird, Robert D.; Jordan, Kristi Y.; Dodge, Kenneth A.; Pettit, Gregory S.; Bates, John E.

    2009-01-01

    A longitudinal, prospective design was used to examine the roles of peer rejection in middle childhood and antisocial peer involvement in early adolescence in the development of adolescent externalizing behavior problems. Both early starter and late starter pathways were considered. Classroom sociometric interviews from ages 6 through 9 years, adolescent reports of peers' behavior at age 13 years, and parent, teacher, and adolescent self-reports of externalizing behavior problems from age 5 through 14 years were available for 400 adolescents. Results indicate that experiencing peer rejection in elementary school and greater involvement with antisocial peers in early adolescence are correlated but that these peer relationship experiences may represent two different pathways to adolescent externalizing behavior problems. Peer rejection experiences, but not involvement with antisocial peers, predict later externalizing behavior problems when controlling for stability in externalizing behavior. Externalizing problems were most common when rejection was experienced repeatedly. Early externalizing problems did not appear to moderate the relation between peer rejection and later problem behavior. Discussion highlights multiple pathways connecting externalizing behavior problems from early childhood through adolescence with peer relationship experiences in middle childhood and early adolescence. PMID:11393650

  7. Association between Parental Involvement in School and Child Conduct, Social, and Internalizing Problems: Teacher Report

    ERIC Educational Resources Information Center

    Kirkhaug, Bente; Drugli, May Britt; Klockner, Christian A.; Morch, Willy-Tore

    2013-01-01

    The present study examined the factor structure of the Teacher Involvement Questionnaire (Involve-T) by means of exploratory factor analysis and examined the association between children's socio-emotional and behavioural problems and teacher-reported parental involvement in school, using structural equation modelling. The study was conducted with…

  8. Solutions of large-scale electromagnetics problems involving dielectric objects with the parallel multilevel fast multipole algorithm.

    PubMed

    Ergül, Özgür

    2011-11-01

    Fast and accurate solutions of large-scale electromagnetics problems involving homogeneous dielectric objects are considered. Problems are formulated with the electric and magnetic current combined-field integral equation and discretized with the Rao-Wilton-Glisson functions. Solutions are performed iteratively by using the multilevel fast multipole algorithm (MLFMA). For the solution of large-scale problems discretized with millions of unknowns, MLFMA is parallelized on distributed-memory architectures using a rigorous technique, namely, the hierarchical partitioning strategy. Efficiency and accuracy of the developed implementation are demonstrated on very large problems involving as many as 100 million unknowns.

  9. The impact of internet gambling on gambling problems: a comparison of moderate-risk and problem Internet and non-Internet gamblers.

    PubMed

    Gainsbury, Sally M; Russell, Alex; Hing, Nerilee; Wood, Robert; Blaszczynski, Alex

    2013-12-01

    Numerous studies have reported higher rates of gambling problems among Internet compared with non-Internet gamblers. However, little research has examined those at risk of developing gambling problems or overall gambling involvement. This study aimed to examine differences between problem and moderate-risk gamblers among Internet and non-Internet gamblers to determine the mechanisms for how Internet gambling may contribute to gambling problems. Australian gamblers (N = 6,682) completed an online survey that included measures of gambling participation, problem gambling severity, and help seeking. Compared with non-Internet gamblers, Internet gamblers were younger, engaged in a greater number of gambling activities, and were more likely to bet on sports. These differences were significantly greater for problem than moderate-risk gamblers. Non-Internet gamblers were more likely to gamble on electronic gaming machines, and a significantly higher proportion of problem gamblers participated in this gambling activity. Non-Internet gamblers were more likely to report health and psychological impacts of problem gambling and having sought help for gambling problems. Internet gamblers who experience gambling-related harms appear to represent a somewhat different group from non-Internet problem and moderate-risk gamblers. This has implications for the development of treatment and prevention programs, which are often based on research that does not cater for differences between subgroups of gamblers. PsycINFO Database Record (c) 2013 APA, all rights reserved.

  10. Used motor oil passes environmental problem

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

    Brinkman, D.W.; Gottlieb, M.; Koelbel, K.

    Purposes of this study were to determine the amount of oil used, oil change practices, disposal methods involved, perceived harmfulness of various disposal methods, and attitudes toward recycling used motor oil. Survey was taken to verify claims made that the do-it-yourselfer (DIY), who changes his own automotive oil, has caused significant environmental problems by dumping the oil down sewers, on the ground, or into landfills as part of their trash. Results show that more than two-thirds of DIYs would save their oil for recycling if it were picked up at their house or if they had a suitable container formore » bringing it to a recycling center.« less

  11. Help for Crippled Children

    NASA Technical Reports Server (NTRS)

    1977-01-01

    Children with cerebral palsy have nervous system defects which lead to muscular spasticity and loss of coordination. Many of these children have great difficulty walking because certain muscles are in a constant state of contraction. Surgical techniques can lengthen muscles or tendons to improve the child's walking pattern, but it is vital to diagnose accurately the particular spasticity problem of each patient; the individual muscles causing the handicap vary greatly from child to child. It is difficult by physical examination alone to determine precisely which muscle groups are most involved. Biotelemetry has provided a solution. For the past two years, the Children's Hospital at Standord, assisted by NASA and the Stanford Biomedical Application Team, has been applying biotelemetry to the cerebral palsy problem.

  12. Object Transportation by Two Mobile Robots with Hand Carts

    PubMed Central

    Hara, Tatsunori

    2014-01-01

    This paper proposes a methodology by which two small mobile robots can grasp, lift, and transport large objects using hand carts. The specific problems involve generating robot actions and determining the hand cart positions to achieve the stable loading of objects onto the carts. These problems are solved using nonlinear optimization, and we propose an algorithm for generating robot actions. The proposed method was verified through simulations and experiments using actual devices in a real environment. The proposed method could reduce the number of robots required to transport large objects with 50–60%. In addition, we demonstrated the efficacy of this task in real environments where errors occur in robot sensing and movement. PMID:27433499

  13. A Benchmark Problem for Development of Autonomous Structural Modal Identification

    NASA Technical Reports Server (NTRS)

    Pappa, Richard S.; Woodard, Stanley E.; Juang, Jer-Nan

    1996-01-01

    This paper summarizes modal identification results obtained using an autonomous version of the Eigensystem Realization Algorithm on a dynamically complex, laboratory structure. The benchmark problem uses 48 of 768 free-decay responses measured in a complete modal survey test. The true modal parameters of the structure are well known from two previous, independent investigations. Without user involvement, the autonomous data analysis identified 24 to 33 structural modes with good to excellent accuracy in 62 seconds of CPU time (on a DEC Alpha 4000 computer). The modal identification technique described in the paper is the baseline algorithm for NASA's Autonomous Dynamics Determination (ADD) experiment scheduled to fly on International Space Station assembly flights in 1997-1999.

  14. Object Transportation by Two Mobile Robots with Hand Carts.

    PubMed

    Sakuyama, Takuya; Figueroa Heredia, Jorge David; Ogata, Taiki; Hara, Tatsunori; Ota, Jun

    2014-01-01

    This paper proposes a methodology by which two small mobile robots can grasp, lift, and transport large objects using hand carts. The specific problems involve generating robot actions and determining the hand cart positions to achieve the stable loading of objects onto the carts. These problems are solved using nonlinear optimization, and we propose an algorithm for generating robot actions. The proposed method was verified through simulations and experiments using actual devices in a real environment. The proposed method could reduce the number of robots required to transport large objects with 50-60%. In addition, we demonstrated the efficacy of this task in real environments where errors occur in robot sensing and movement.

  15. The medicolegal and forensic aspects of fires.

    PubMed

    Eckert, W G

    1981-12-01

    Fires, their consequences and their investigations, continue to provide forensic scientists, especially those involved in medicolegal investigation (the medical examiner or forensic pathologist), with constant work and variations in problems. The recent history of mass disasters involving high-rise buildings, transport accidents, and arson-related accidents in nightclubs and prisons has emphasized the necessity for corrective and preventive means to ensure safety to the occupants of any of these areas. Problems presented by fires include the determination of the cause of the fire, the identification of the victims, and the cause and manner of their deaths. The motivation of the fire setter and the settlement by the insurance company or legal means are also aspects to be considered. The imperceptible effects of the fires include many other aspects, among which loss of loved ones and family providers and loss of industrial revenue and job potential are all felt. The most frightening development of all, however, is the insidious surfacing of arson as a possible factor in many major fires. The most recent tragedies involving the Stouffer Inn fire and the Hilton International Hotel fire were both related to arsonous acts. The scope of this article is to review the subject as it affects the forensic medical practitioner directly or indirectly so that his or her investigation may be brought to completion in conjunction with other authorities involved in the case.

  16. Programmable Infusion Pumps in ICUs: An Analysis of Corresponding Adverse Drug Events

    PubMed Central

    Bower, Anthony G.; Paddock, Susan M.; Hilborne, Lee H.; Wallace, Peggy; Rothschild, Jeffrey M.; Griffin, Anne; Fairbanks, Rollin J.; Carlson, Beverly; Panzer, Robert J.; Brook, Robert H.

    2007-01-01

    Background Patients in intensive care units (ICUs) frequently experience adverse drug events involving intravenous medications (IV-ADEs), which are often preventable. Objectives To determine how frequently preventable IV-ADEs in ICUs match the safety features of a programmable infusion pump with safety software (“smart pump”) and to suggest potential improvements in smart-pump design. Design Using retrospective medical-record review, we examined preventable IV-ADEs in ICUs before and after 2 hospitals replaced conventional pumps with smart pumps. The smart pumps alerted users when programmed to deliver duplicate infusions or continuous-infusion doses outside hospital-defined ranges. Participants 4,604 critically ill adults at 1 academic and 1 nonacademic hospital. Measurements Preventable IV-ADEs matching smart-pump features and errors involved in preventable IV-ADEs. Results Of 100 preventable IV-ADEs identified, 4 involved errors matching smart-pump features. Two occurred before and 2 after smart-pump implementation. Overall, 29% of preventable IV-ADEs involved overdoses; 37%, failures to monitor for potential problems; and 45%, failures to intervene when problems appeared. Error descriptions suggested that expanding smart pumps’ capabilities might enable them to prevent more IV-ADEs. Conclusion The smart pumps we evaluated are unlikely to reduce preventable IV-ADEs in ICUs because they address only 4% of them. Expanding smart-pump capabilities might prevent more IV-ADEs. PMID:18095043

  17. The Roles of Internal Representation and Processing in Problem Solving Involving Insight: A Computational Complexity Perspective

    ERIC Educational Resources Information Center

    Wareham, Todd

    2017-01-01

    In human problem solving, there is a wide variation between individuals in problem solution time and success rate, regardless of whether or not this problem solving involves insight. In this paper, we apply computational and parameterized analysis to a plausible formalization of extended representation change theory (eRCT), an integration of…

  18. Proton-beam technique dates fine wine

    NASA Astrophysics Data System (ADS)

    Dumé, Belle

    2008-10-01

    Nuclear physicists in France have invented a way to authenticate the vintage of rare wine without needing a sommelier's keen nose or even a corkscrew. The technique, which involves firing high-energy protons at wine bottles, can determine how old the bottles are and even where they come from. The new method could help unmask counterfeit wines - a growing problem in the fine-wine industry, where a bottle can sell for thousands of Euros.

  19. Basic Economic Principles

    NASA Technical Reports Server (NTRS)

    Tideman, T. N.

    1972-01-01

    An economic approach to design efficient transportation systems involves maximizing an objective function that reflects both goals and costs. A demand curve can be derived by finding the quantities of a good that solve the maximization problem as one varies the price of that commodity, holding income and the prices of all other goods constant. A supply curve is derived by applying the idea of profit maximization of firms. The production function determines the relationship between input and output.

  20. Choosing appropriate independent variable in educational experimental research: some errors debunked

    NASA Astrophysics Data System (ADS)

    Panjaitan, R. L.

    2018-03-01

    It is found that a number of quantitative research reports of some beginning researchers, especially undergraduate students, tend to ‘merely’ quantitative with not really proper understanding of variables involved in the research. This paper focuses on some mistakes related to independent variable determination in experimental research in education. With literature research methodology, data were gathered from an undergraduate student’s thesis as a single non-human subject. This data analysis resulted some findings, such as misinterpreted variables that should have represented the research question, and unsuitable calculation of determination coefficient due to incorrect independent variable determination. When a researcher misinterprets data as data that could behave as the independent variable but actually it could not, all of the following data processes become pointless. These problems might lead to inaccurate research conclusion. In this paper, the problems were analysed and discussed. To avert the incorrectness in processing data, it is suggested that undergraduate students as beginning researchers have adequate statistics mastery. This study might function as a resource to researchers in education to be aware to and not to redo similar errors.

  1. Skin problems after a tsunami.

    PubMed

    Lee, S H; Choi, C P; Eun, H C; Kwon, O S

    2006-08-01

    On December 26, 2004, the biggest earthquake for 40 years, measuring 9.0 on the Richter scale, triggered a tsunami that pounded the coastal areas of South Asia and East Africa. The effects of the tsunami on skin conditions have not been evaluated. To determine the influence of the tsunami on skin conditions by evaluating the skin problems of patients presenting at hospitals after the tsunami. Between 5 and 25 January 2005, two dermatologists evaluated patients who complained of skin problems at an outpatient clinic and emergency room of a general hospital in Banda Aceh, Aceh Province, Indonesia. The total number of patients that presented during the study period was 235 (131 males and 104 females), and they had a total of 265 skin problems. In terms of age distribution, most subjects were in their fourth decade (23.0%), followed by the third (22.6%) and fifth decade (16.6%). The most prevalent skin problems were infections-infestations (32.5%), followed by eczemas (29.8%) and traumatic skin disorders (29.4%). In males, traumatic skin disorders were most common. The great majority of infection-infestation cases involved superficial fungal infections. Contact dermatitis accounted for three-quarters of eczema cases, and mainly involved the arms (40.0%) and legs (27.1%). The majority of traumatic skin disorders were lacerations, punctures and penetrations, and the feet (44.7%) and hands (18.8%) were most frequently affected. Unhygienic conditions, exposure to a hazardous environment and contact with various objects during and after the tsunami probably increased the prevalence of infections-infestations, traumatic skin disorders and contact dermatitis. To prevent these problems and associated secondary bacterial infections, health-related education and early medical management are required.

  2. Mediating effects of depression and anxiety on the relationship between bullying involvement and pain problems among adolescents in Taiwan.

    PubMed

    Yen, Cheng-Fang; Lin, I-Mei; Liu, Tai-Ling; Hu, Huei-Fan; Cheng, Chung-Ping

    2014-08-01

    This study aimed to examine the mediating effects of depression and anxiety on the relationships of bullying victimization and perpetration with pain among adolescents in Taiwan. A total of 4976 students of junior and senior high schools completed the questionnaires. Bullying victimization and perpetration, pain problems, depression, and anxiety were assessed. The mediating effects of depression and anxiety on the relationship between bullying involvement and pain problems and the moderating effects of sex on the medicating roles of depression and anxiety were examined by structural equation model. Both depression and anxiety were significant mediators of the relationship between bullying victimization and pain problems among adolescents. Depression was also a significant mediator of the relationship between bullying perpetration and pain problems among adolescents. Sex had no moderating effect on the mediating role of depression/anxiety on the association between bullying involvement and pain problems. Medical and educational professionals should survey and intervene in depression and anxiety when managing pain problems among adolescents involved in bullying. Copyright © 2014 Elsevier Inc. All rights reserved.

  3. Cultural Variability in Crew Discourse

    NASA Technical Reports Server (NTRS)

    Fischer, Ute

    1999-01-01

    Four studies were conducted to determine features of effective crew communication in response to errors during flight. Study One examined whether US captains and first officers use different communication strategies to correct errors and problems on the flight deck, and whether their communications are affected by the two situation variables, level of risk and degree of face-threat involved in challenging an error. Study Two was the cross-cultural extension of Study One and involved pilots from three European countries. Study Three compared communication strategies of female and male air carrier pilots who were matched in terms of years and type of aircraft experience. The final study assessed the effectiveness of the communication strategies observed in Study One.

  4. Differences in managerial behaviour between head nurses and medical directors in intensive care units in Europe.

    PubMed

    Pepermans, R; Mentens, C; Goedee, M; Jegers, M; van Roy, K

    2001-01-01

    We attempt to determine whether differences appear between the managerial behaviour of European intensive care head nurses on the one side and medical directors on the other. In order to come up with a managerial job and competency analysis of ICU managers, observations and interviews were performed. Additionally, focus groups consisting of ICU experts were organized. The results are discussed according to managerial behaviour taxonomies and existing competency models. There seems to be some differentiation between the two managerial positions studied. Head nurses are more involved in planning/coordinating and motivating/reinforcing activities, whereas medical directors are more involved in socializing/politicking, decision making/problem solving, interaction with others and disciplining.

  5. Responding to Family Problems, Alcohol and Substance Misuse. A Survey of Service Provision in the Glasgow Area.

    ERIC Educational Resources Information Center

    McKellar, Susan; Coggans, Niall

    1997-01-01

    Surveyed social agencies' awareness of possible developmental problems of alcohol and substance abusers' children, extent to which agency felt it could deal with the problem involving the family, and development of services for children of substance abusers. Found that many agency workers considered involvement in family problems to be part of…

  6. A New Classification of Endodontic-Periodontal Lesions

    PubMed Central

    Al-Fouzan, Khalid S.

    2014-01-01

    The interrelationship between periodontal and endodontic disease has always aroused confusion, queries, and controversy. Differentiating between a periodontal and an endodontic problem can be difficult. A symptomatic tooth may have pain of periodontal and/or pulpal origin. The nature of that pain is often the first clue in determining the etiology of such a problem. Radiographic and clinical evaluation can help clarify the nature of the problem. In some cases, the influence of pulpal pathology may cause the periodontal involvement and vice versa. The simultaneous existence of pulpal problems and inflammatory periodontal disease can complicate diagnosis and treatment planning. An endo-perio lesion can have a varied pathogenesis which ranges from simple to relatively complex one. The differential diagnosis of endodontic and periodontal diseases can sometimes be difficult, but it is of vital importance to make a correct diagnosis for providing the appropriate treatment. This paper aims to discuss a modified clinical classification to be considered for accurately diagnosing and treating endo-perio lesion. PMID:24829580

  7. A new classification of endodontic-periodontal lesions.

    PubMed

    Al-Fouzan, Khalid S

    2014-01-01

    The interrelationship between periodontal and endodontic disease has always aroused confusion, queries, and controversy. Differentiating between a periodontal and an endodontic problem can be difficult. A symptomatic tooth may have pain of periodontal and/or pulpal origin. The nature of that pain is often the first clue in determining the etiology of such a problem. Radiographic and clinical evaluation can help clarify the nature of the problem. In some cases, the influence of pulpal pathology may cause the periodontal involvement and vice versa. The simultaneous existence of pulpal problems and inflammatory periodontal disease can complicate diagnosis and treatment planning. An endo-perio lesion can have a varied pathogenesis which ranges from simple to relatively complex one. The differential diagnosis of endodontic and periodontal diseases can sometimes be difficult, but it is of vital importance to make a correct diagnosis for providing the appropriate treatment. This paper aims to discuss a modified clinical classification to be considered for accurately diagnosing and treating endo-perio lesion.

  8. A hybrid computer program for rapidly solving flowing or static chemical kinetic problems involving many chemical species

    NASA Technical Reports Server (NTRS)

    Mclain, A. G.; Rao, C. S. R.

    1976-01-01

    A hybrid chemical kinetic computer program was assembled which provides a rapid solution to problems involving flowing or static, chemically reacting, gas mixtures. The computer program uses existing subroutines for problem setup, initialization, and preliminary calculations and incorporates a stiff ordinary differential equation solution technique. A number of check cases were recomputed with the hybrid program and the results were almost identical to those previously obtained. The computational time saving was demonstrated with a propane-oxygen-argon shock tube combustion problem involving 31 chemical species and 64 reactions. Information is presented to enable potential users to prepare an input data deck for the calculation of a problem.

  9. On anthropic solutions of the cosmological constant problem

    NASA Astrophysics Data System (ADS)

    Banks, Tom; Dine, Michael; Motl, Lubos

    2001-01-01

    Motivated by recent work of Bousso and Polchinski (BP), we study theories which explain the small value of the cosmological constant using the anthropic principle. We argue that simultaneous solution of the gauge hierarchy problem is a strong constraint on any such theory. We exhibit three classes of models which satisfy these constraints. The first is a version of the BP model with precisely two large dimensions. The second involves 6-branes and antibranes wrapped on supersymmetric 3-cycles of Calabi-Yau manifolds, and the third is a version of the irrational axion model. All of them have possible problems in explaining the size of microwave background fluctuations. We also find that most models of this type predict that all constants in the low energy lagrangian, as well as the gauge groups and representation content, are chosen from an ensemble and cannot be uniquely determined from the fundamental theory. In our opinion, this significantly reduces the appeal of this kind of solution of the cosmological constant problem. On the other hand, we argue that the vacuum selection problem of string theory might plausibly have an anthropic, cosmological solution.

  10. A Cognitive Model for Problem Solving in Computer Science

    ERIC Educational Resources Information Center

    Parham, Jennifer R.

    2009-01-01

    According to industry representatives, computer science education needs to emphasize the processes involved in solving computing problems rather than their solutions. Most of the current assessment tools used by universities and computer science departments analyze student answers to problems rather than investigating the processes involved in…

  11. Problem Solving through Paper Folding

    ERIC Educational Resources Information Center

    Wares, Arsalan

    2014-01-01

    The purpose of this article is to describe a couple of challenging mathematical problems that involve paper folding. These problem-solving tasks can be used to foster geometric and algebraic thinking among students. The context of paper folding makes some of the abstract mathematical ideas involved relatively concrete. When implemented…

  12. The link between drinking and gambling among undergraduate university students.

    PubMed

    Hodgins, David C; Racicot, Stephanie

    2013-09-01

    The purpose of this research was to explore different aspects of the link between alcohol use and gambling among undergraduate university students (N = 121). Potential aspects of the link examined included level of involvement in each behavior, consequences, motives for involvement, and impaired control over involvement. Results confirmed that drinking and gambling among university students are associated, consistent with the expectations of a problem syndrome model. The strongest link was between general dimensions of problematic involvement for both behaviors. Students who drink to cope and have other indicators of alcohol problems are more likely to gamble to cope, gamble to win money, and have higher gambling involvement and gambling-related problems. However, the salience of drinking and gambling to cope in this relationship is an interesting finding that needs further exploration and extension to other problem behaviors. PsycINFO Database Record (c) 2013 APA, all rights reserved.

  13. Breadth and depth involvement: Understanding Internet gambling involvement and its relationship to gambling problems.

    PubMed

    LaPlante, Debi A; Nelson, Sarah E; Gray, Heather M

    2014-06-01

    The "involvement effect" refers to the finding that controlling for gambling involvement often reduces or eliminates frequently observed game-specific associations with problem gambling. In other words, broader patterns of gambling behavior, particularly the number of types of games played over a defined period, contribute more to problem gambling than playing specific games (e.g., lottery, casino, Internet gambling). This study extends this burgeoning area of inquiry in three primary ways. First, it tests independently and simultaneously the predictive power of two gambling patterns: breadth involvement (i.e., the number of games an individual plays) and depth involvement (i.e., the number of days an individual plays). Second, it includes the first involvement analyses of actual betting activity records that are associated with clinical screening information. Third, it evaluates and compares the linearity of breadth and depth effects. We conducted analyses of the actual gambling activity of 1,440 subscribers to the bwin.party gambling service who completed an online gambling disorder screen. In all, 11 of the 16 games we examined had a significant univariate association with a positive screen for gambling disorder. However, after controlling for breadth involvement, only Live Action Internet sports betting retained a significant relationship with potential gambling-related problems. Depth involvement, though significantly related to potential problems, did not impact game-based gambling disorder associations as much as breadth involvement. Finally, breadth effects appeared steeply linear, with a slight quadratic component manifesting beyond four games played, but depth effects appeared to have a strong linear component and a slight cubic component.

  14. Remote monitoring of environmental particulate pollution - A problem in inversion of first-kind integral equations

    NASA Technical Reports Server (NTRS)

    Fymat, A. L.

    1975-01-01

    The determination of the microstructure, chemical nature, and dynamical evolution of scattering particulates in the atmosphere is considered. A description is given of indirect sampling techniques which can circumvent most of the difficulties associated with direct sampling techniques, taking into account methods based on scattering, extinction, and diffraction of an incident light beam. Approaches for reconstructing the particulate size distribution from the direct and the scattered radiation are discussed. A new method is proposed for determining the chemical composition of the particulates and attention is given to the relevance of methods of solution involving first kind Fredholm integral equations.

  15. Adjustment Problems and Multiple Intelligences among Gifted Students in Hong Kong: The Development of the Revised Student Adjustment Problems Inventory.

    ERIC Educational Resources Information Center

    Chan, David W.

    2003-01-01

    A study involving 639 Chinese gifted students (grades 4-12) found that intense emotional involvement, perfectionism, unchallenging schoolwork, multipotentiality, and parental expectations were relatively common adjustment problems. Poor interpersonal relationships were not. Results also indicated that conventional intelligence increased…

  16. Proportional Reasoning in the Learning of Chemistry: Levels of Complexity

    ERIC Educational Resources Information Center

    Ramful, Ajay; Narod, Fawzia Bibi

    2014-01-01

    This interdisciplinary study sketches the ways in which proportional reasoning is involved in the solution of chemistry problems, more specifically, problems involving quantities in chemical reactions (commonly referred to as stoichiometry problems). By building on the expertise of both mathematics and chemistry education research, the present…

  17. An Action-Research Program for Increasing Employee Involvement in Problem Solving.

    ERIC Educational Resources Information Center

    Pasmore, William; Friedlander, Frank

    1982-01-01

    Describes the use of participative action research to solve problems of work-related employee injuries in a rural midwestern electronics plant by increasing employee involvement. The researchers established an employee problem-solving group that interviewed and surveyed workers, analyzed the results, and suggested new work arrangements. (Author/RW)

  18. Generic Science Skills Enhancement of Students through Implementation of IDEAL Problem Solving Model on Genetic Information Course

    NASA Astrophysics Data System (ADS)

    Zirconia, A.; Supriyanti, F. M. T.; Supriatna, A.

    2018-04-01

    This study aims to determine generic science skills enhancement of students through implementation of IDEAL problem-solving model on genetic information course. Method of this research was mixed method, with pretest-posttest nonequivalent control group design. Subjects of this study were chemistry students enrolled in biochemistry course, consisted of 22 students in the experimental class and 19 students in control class. The instrument in this study was essayed involves 6 indicators generic science skills such as indirect observation, causality thinking, logical frame, self-consistent thinking, symbolic language, and developing concept. The results showed that genetic information course using IDEAL problem-solving model have been enhancing generic science skills in low category with of 20,93%. Based on result for each indicator, showed that there are indicators of generic science skills classified in the high category.

  19. A Chebyshev Collocation Method for Moving Boundaries, Heat Transfer, and Convection During Directional Solidification

    NASA Technical Reports Server (NTRS)

    Zhang, Yiqiang; Alexander, J. I. D.; Ouazzani, J.

    1994-01-01

    Free and moving boundary problems require the simultaneous solution of unknown field variables and the boundaries of the domains on which these variables are defined. There are many technologically important processes that lead to moving boundary problems associated with fluid surfaces and solid-fluid boundaries. These include crystal growth, metal alloy and glass solidification, melting and name propagation. The directional solidification of semi-conductor crystals by the Bridgman-Stockbarger method is a typical example of such a complex process. A numerical model of this growth method must solve the appropriate heat, mass and momentum transfer equations and determine the location of the melt-solid interface. In this work, a Chebyshev pseudospectra collocation method is adapted to the problem of directional solidification. Implementation involves a solution algorithm that combines domain decomposition, finite-difference preconditioned conjugate minimum residual method and a Picard type iterative scheme.

  20. Diagnostic problems associated with cadaveric trauma from animal activity.

    PubMed

    Byard, Roger W; James, Ross A; Gilbert, John D

    2002-09-01

    Analysis of a series of deaths between 1986 and 2001 resulting from natural disease, accidents, suicides, and homicide, where postmortem animal activity had traumatized bodies, was undertaken at the Forensic Science Center in Adelaide to demonstrate the range of lesions that may occur and problems in interpretation that result. Tissue damage had been caused by a variety of animals, including fly larvae, ants, birds, dogs, rodents, sea lice, and sharks. Postmortem animal activity had disguised injuries, modified wounds, and created the appearances of inflicted injury. Problems with identification occurred after postmortem facial trauma, and loss of organ parenchyma had interfered with, or precluded, the precise determination of the manner of death in some cases. Specific kinds of tissue and organ damage may occur after death, necessitating careful assessment of lesions in a search for characteristic features of animal activity. The pattern of lesions may enable identification of the particular species of animal involved.

  1. Students' conceptual performance on synthesis physics problems with varying mathematical complexity

    NASA Astrophysics Data System (ADS)

    Ibrahim, Bashirah; Ding, Lin; Heckler, Andrew F.; White, Daniel R.; Badeau, Ryan

    2017-06-01

    A body of research on physics problem solving has focused on single-concept problems. In this study we use "synthesis problems" that involve multiple concepts typically taught in different chapters. We use two types of synthesis problems, sequential and simultaneous synthesis tasks. Sequential problems require a consecutive application of fundamental principles, and simultaneous problems require a concurrent application of pertinent concepts. We explore students' conceptual performance when they solve quantitative synthesis problems with varying mathematical complexity. Conceptual performance refers to the identification, follow-up, and correct application of the pertinent concepts. Mathematical complexity is determined by the type and the number of equations to be manipulated concurrently due to the number of unknowns in each equation. Data were collected from written tasks and individual interviews administered to physics major students (N =179 ) enrolled in a second year mechanics course. The results indicate that mathematical complexity does not impact students' conceptual performance on the sequential tasks. In contrast, for the simultaneous problems, mathematical complexity negatively influences the students' conceptual performance. This difference may be explained by the students' familiarity with and confidence in particular concepts coupled with cognitive load associated with manipulating complex quantitative equations. Another explanation pertains to the type of synthesis problems, either sequential or simultaneous task. The students split the situation presented in the sequential synthesis tasks into segments but treated the situation in the simultaneous synthesis tasks as a single event.

  2. A modified Wright-Fisher model that incorporates Ne: A variant of the standard model with increased biological realism and reduced computational complexity.

    PubMed

    Zhao, Lei; Gossmann, Toni I; Waxman, David

    2016-03-21

    The Wright-Fisher model is an important model in evolutionary biology and population genetics. It has been applied in numerous analyses of finite populations with discrete generations. It is recognised that real populations can behave, in some key aspects, as though their size that is not the census size, N, but rather a smaller size, namely the effective population size, Ne. However, in the Wright-Fisher model, there is no distinction between the effective and census population sizes. Equivalently, we can say that in this model, Ne coincides with N. The Wright-Fisher model therefore lacks an important aspect of biological realism. Here, we present a method that allows Ne to be directly incorporated into the Wright-Fisher model. The modified model involves matrices whose size is determined by Ne. Thus apart from increased biological realism, the modified model also has reduced computational complexity, particularly so when Ne⪡N. For complex problems, it may be hard or impossible to numerically analyse the most commonly-used approximation of the Wright-Fisher model that incorporates Ne, namely the diffusion approximation. An alternative approach is simulation. However, the simulations need to be sufficiently detailed that they yield an effective size that is different to the census size. Simulations may also be time consuming and have attendant statistical errors. The method presented in this work may then be the only alternative to simulations, when Ne differs from N. We illustrate the straightforward application of the method to some problems involving allele fixation and the determination of the equilibrium site frequency spectrum. We then apply the method to the problem of fixation when three alleles are segregating in a population. This latter problem is significantly more complex than a two allele problem and since the diffusion equation cannot be numerically solved, the only other way Ne can be incorporated into the analysis is by simulation. We have achieved good accuracy in all cases considered. In summary, the present work extends the realism and tractability of an important model of evolutionary biology and population genetics. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Analysis of a spacecraft instrument ball bearing assembly lubricated by a perfluoroalkylether

    NASA Technical Reports Server (NTRS)

    Morales, W.; Jones, W. R., Jr.; Buckley, D. H.

    1986-01-01

    An analysis of a spacecraft instrument ball bearing assembly, subjected to a scanning life test, was performed to determine the possible case of rotational problems involving these units aboard several satellites. The analysis indicated an ineffective transfer of a fluorinated liquid lubricant from a phenolic retainer to the bearing balls. Part of the analysis led to a novel HPLC separation method employing a fluorinated mobile phase in conjunction with silica based size exclusion columns.

  4. The Design of an Information Management Program for Headquarters, Department of the Army. Phase 2. Detailed Report.

    DTIC Science & Technology

    1980-02-26

    information management problems identified by Arthur Young & Companyt , Phase I and Phase II study for Headquarters, Department of the Army. The discussions...current HQDA operations were conducted to allow Arthur Young & Company to determine what is needed and what is feasible for managing HQDA’s information...answering these inquiries, and what costs were involved in satisfying the information request. The selection of individual case studies was based upon

  5. The Media and Democracy in Russia

    DTIC Science & Technology

    2005-06-01

    actors must be determined in the pursuit of their goals, use their resources prudently and effectively, combine the capacity to govern with...problems can come from either the state, or non-state actors .13 The overall status of Russia has fallen from partly free to not free during the...glorifying the state, or in which the state is even a central actor . The idea of the statute is to involve the state as little as possible, to move toward

  6. [Problems in the individual adaptation of working women].

    PubMed

    Grebeneva, O V; Balaeva, E A

    2008-01-01

    The mechanisms of development of dysadaptive changes were revealed in factory workers in relation to congenital personality traits and the schemes of individual adaptation strategies were defined. At the same time increased anxiety leading to the accelerated rates of aging preceded impaired adaptive processes. The differences in the female adaptive patterns were determined by both the degree of emotional stability and the baseline energy capacities of the cardiorespiratory system and the involvement of a mental component in adaptation.

  7. Alternative Perspectives on Risk: Individual Differences in Problem Structuring

    NASA Technical Reports Server (NTRS)

    Orasanu, Judith; Fischer, Ute; Connors, Mary M. (Technical Monitor)

    1997-01-01

    Team decision making involves contributions of multiple players toward a common goal. While much has been written about the importance of developing shared mental models in order for teams to work together effectively, little has been done to determine the value of alternative perspectives on problem solving and decision making. Early studies of expertise contrasted experts with novices and noted that the two groups differ in the way they structure problems and in their selection of information as salient. Little attention has been given to differences among experts who differ in their specializations. A series of experiments was conducted to determine: (1) what dimensions of flight-related problem situations pilots judge to be most important when making flight-relevant decisions; and (2) whether pilots in different crew positions differ in the way they interpret problems relating to flight decisions. A sorting task was used to identify underlying dimensions judged as salient to individual pilots. Captains, first officers, and flight engineers from two major carriers participated in the study. Twenty-two flight scenarios were developed based on ASRS reports. Pilots were required to make judgments about how they would respond in each case and to sort the scenarios on the basis of similarity of decision factors. They were also asked to provide a verbal label that described each of their sorted categories. A second study required a different group of pilots (also captains, first officers and flight engineers) to sort on predetermined bases.

  8. Less reduction of psychosocial problems among adolescents with unmet communication needs.

    PubMed

    Jager, Margot; Reijneveld, Sijmen A; Almansa, Josue; Metselaar, Janneke; Knorth, Erik J; De Winter, Andrea F

    2017-04-01

    Patient-professional communication has been suggested to be a major determinant of treatment outcomes in psychosocial care for children and adolescents. However, the mechanisms involved are largely unknown and no longitudinal studies have been performed. Our aim was, therefore, to assess over the course of 1 year, the impact of patient-centered communication on psychosocial problems of adolescents in psychosocial care, including the routes mediating this impact. We obtained data on 315 adolescents, aged 12-18 years, enrolled in child and adolescent social or mental health care. We assessed patient-centered communication by comparing the needs and experiences of adolescents with regard to three aspects of communication: affective quality, information provision, and shared decision-making. Changes in psychosocial problems comprised those reported by adolescents and their parents between baseline and 1 year thereafter. Potential mediators were treatment adherence, improvement of understanding, and improvement in self-confidence. We found a relationship between unmet needs for affective quality, information provision, and shared decision-making and less reduction of psychosocial problems. The association between the unmet need to share in decision-making and less reduction of psychosocial problems were partially mediated by less improvement in self-confidence (30 %). We found no mediators regarding affective quality and information provision. Our findings confirm that patient-centered communication is a major determinant of treatment outcomes in psychosocial care for adolescents. Professionals should be aware that tailoring their communication to individual patients' needs is vital to the effectiveness of psychosocial care.

  9. An Inverse Interpolation Method Utilizing In-Flight Strain Measurements for Determining Loads and Structural Response of Aerospace Vehicles

    NASA Technical Reports Server (NTRS)

    Shkarayev, S.; Krashantisa, R.; Tessler, A.

    2004-01-01

    An important and challenging technology aimed at the next generation of aerospace vehicles is that of structural health monitoring. The key problem is to determine accurately, reliably, and in real time the applied loads, stresses, and displacements experienced in flight, with such data establishing an information database for structural health monitoring. The present effort is aimed at developing a finite element-based methodology involving an inverse formulation that employs measured surface strains to recover the applied loads, stresses, and displacements in an aerospace vehicle in real time. The computational procedure uses a standard finite element model (i.e., "direct analysis") of a given airframe, with the subsequent application of the inverse interpolation approach. The inverse interpolation formulation is based on a parametric approximation of the loading and is further constructed through a least-squares minimization of calculated and measured strains. This procedure results in the governing system of linear algebraic equations, providing the unknown coefficients that accurately define the load approximation. Numerical simulations are carried out for problems involving various levels of structural approximation. These include plate-loading examples and an aircraft wing box. Accuracy and computational efficiency of the proposed method are discussed in detail. The experimental validation of the methodology by way of structural testing of an aircraft wing is also discussed.

  10. Determination of criteria weights in solving multi-criteria problems

    NASA Astrophysics Data System (ADS)

    Kasim, Maznah Mat

    2014-12-01

    A multi-criteria (MC) problem comprises of units to be analyzed under a set of evaluation criteria. Solving a MC problem is basically the process of finding the overall performance or overall quality of the units of analysis by using certain aggregation method. Based on these overall measures of each unit, a decision can be made whether to sort them, to select the best or to group them according to certain ranges. Prior to solving the MC problems, the weights of the related criteria have to be determined with the assumption that the weights represent the degree of importance or the degree of contribution towards the overall performance of the units. This paper presents two main approaches which are called as subjective and objective approaches, where the first one involves evaluator(s) while the latter approach depends on the intrinsic information contained in each criterion. The subjective and objective weights are defined if the criteria are assumed to be independent with each other, but if they are dependent, there is another type of weight, which is called as monotone measure weight or compound weights which represent degree of interaction among the criteria. The measure of individual weights or compound weights must be addressed in solving multi-criteria problems so that the solutions are more reliable since in the real world, evaluation criteria always come with different degree of importance or are dependent with each other. As the real MC problems have their own uniqueness, it is up to the decision maker(s) to decide which type of weights and which method are the most applicable ones for the problem under study.

  11. Parallel Simulation of Three-Dimensional Free Surface Fluid Flow Problems

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

    BAER,THOMAS A.; SACKINGER,PHILIP A.; SUBIA,SAMUEL R.

    1999-10-14

    Simulation of viscous three-dimensional fluid flow typically involves a large number of unknowns. When free surfaces are included, the number of unknowns increases dramatically. Consequently, this class of problem is an obvious application of parallel high performance computing. We describe parallel computation of viscous, incompressible, free surface, Newtonian fluid flow problems that include dynamic contact fines. The Galerkin finite element method was used to discretize the fully-coupled governing conservation equations and a ''pseudo-solid'' mesh mapping approach was used to determine the shape of the free surface. In this approach, the finite element mesh is allowed to deform to satisfy quasi-staticmore » solid mechanics equations subject to geometric or kinematic constraints on the boundaries. As a result, nodal displacements must be included in the set of unknowns. Other issues discussed are the proper constraints appearing along the dynamic contact line in three dimensions. Issues affecting efficient parallel simulations include problem decomposition to equally distribute computational work among a SPMD computer and determination of robust, scalable preconditioners for the distributed matrix systems that must be solved. Solution continuation strategies important for serial simulations have an enhanced relevance in a parallel coquting environment due to the difficulty of solving large scale systems. Parallel computations will be demonstrated on an example taken from the coating flow industry: flow in the vicinity of a slot coater edge. This is a three dimensional free surface problem possessing a contact line that advances at the web speed in one region but transitions to static behavior in another region. As such, a significant fraction of the computational time is devoted to processing boundary data. Discussion focuses on parallel speed ups for fixed problem size, a class of problems of immediate practical importance.« less

  12. Mental Health and School Functioning for Girls in the Child Welfare System: the Mediating Role of Future Orientation and School Engagement.

    PubMed

    Threlfall, Jennifer M; Auslander, Wendy; Gerke, Donald; McGinnis, Hollee; Myers Tlapek, Sarah

    2017-01-01

    This study investigated the association between mental health problems and academic and behavioral school functioning for adolescent girls in the child welfare system and determined whether school engagement and future orientation meditated the relationship. Participants were 231 girls aged between 12 and 19 who had been involved with the child welfare system. Results indicated that 39% of girls reported depressive symptoms in the clinical range and 54% reported posttraumatic symptoms in the clinical range. The most common school functioning problems reported were failing a class (41%) and physical fights with other students (35%). Participants reported a mean number of 1.7 school functioning problems. Higher levels of depression and PTSD were significantly associated with more school functioning problems. School engagement fully mediated the relationship between depression and school functioning and between PTSD and school functioning, both models controlling for age, race, and placement stability. Future orientation was not significantly associated with school functioning problems at the bivariate level. Findings suggest that school engagement is a potentially modifiable target for interventions aiming to ameliorate the negative influence of mental health problems on school functioning for adolescent girls with histories of abuse or neglect.

  13. Adolescent cigarette smoking: health-related behavior or normative transgression?

    PubMed

    Turbin, M S; Jessor, R; Costa, F M

    2000-09-01

    Relations among measures of adolescent behavior were examined to determine whether cigarette smoking fits into a structure of problem behaviors-behaviors that involve normative transgression-or a structure of health-related behaviors, or both. In an ethnically and socioeconomically diverse sample of 1782 male and female high school adolescents, four first-order problem behavior latent variables-sexual intercourse experience, alcohol abuse, illicit drug use, and delinquency-were established and together were shown to reflect a second-order latent variable of problem behavior. Four first-order latent variables of health-related behaviors-unhealthy dietary habits, sedentary behavior, unsafe behavior, and poor dental hygiene-were also established and together were shown to reflect a second-order latent variable of health-compromising behavior. The structure of relations among those latent variables was modeled. Cigarette smoking had a significant and substantial loading only on the problem-behavior latent variable; its loading on the health-compromising behavior latent variable was essentially zero. Adolescent cigarette smoking relates strongly and directly to problem behaviors and only indirectly, if at all, to health-compromising behaviors. Interventions to prevent or reduce adolescent smoking should attend more to factors that influence problem behaviors.

  14. Solution of the advection-dispersion equation by a finite-volume eulerian-lagrangian local adjoint method

    USGS Publications Warehouse

    Healy, R.W.; Russell, T.F.

    1992-01-01

    A finite-volume Eulerian-Lagrangian local adjoint method for solution of the advection-dispersion equation is developed and discussed. The method is mass conservative and can solve advection-dominated ground-water solute-transport problems accurately and efficiently. An integrated finite-difference approach is used in the method. A key component of the method is that the integral representing the mass-storage term is evaluated numerically at the current time level. Integration points, and the mass associated with these points, are then forward tracked up to the next time level. The number of integration points required to reach a specified level of accuracy is problem dependent and increases as the sharpness of the simulated solute front increases. Integration points are generally equally spaced within each grid cell. For problems involving variable coefficients it has been found to be advantageous to include additional integration points at strategic locations in each well. These locations are determined by backtracking. Forward tracking of boundary fluxes by the method alleviates problems that are encountered in the backtracking approaches of most characteristic methods. A test problem is used to illustrate that the new method offers substantial advantages over other numerical methods for a wide range of problems.

  15. Differential Effects of Counselor Self-Disclosure, Self-Involving Statements, and Interpretation.

    ERIC Educational Resources Information Center

    Dowd, E. Thomas; Boroto, Daniel R.

    1982-01-01

    College students (N=217) rated counselor characteristics after viewing a simulated counseling session ending with the counselor summarizing the session, disclosing a past personal problem, disclosing a present personal problem, engaging in self-involving statements, or offering dynamic interpretations. Self-disclosure and self-involving statements…

  16. Cross-national Consistency in the Relationship Between Bullying Behaviors and Psychosocial Adjustment

    PubMed Central

    Nansel, Tonja R.; Craig, Wendy; Overpeck, Mary D.; Saluja, Gitanjali; Ruan, W. June

    2008-01-01

    Objective To determine whether the relationship between bullying and psychosocial adjustment is consistent across countries by standard measures and methods. Design Cross-sectional self-report surveys were obtained from nationally representative samples of students in 25 countries. Involvement in bullying, as bully, victim, or both bully and victim, was assessed. Setting Surveys were conducted at public and private schools throughout the participating countries. Participants Participants included all consenting students in sampled classrooms, for a total of 113200 students at average ages of 11.5, 13.5, and 15.5 years. Main Outcome Measures Psychosocial adjustment dimensions assessed included health problems, emotional adjustment, school adjustment, relationships with classmates, alcohol use, and weapon carrying. Results Involvement in bullying varied dramatically across countries, ranging from 9% to 54% of youth. However, across all countries, involvement in bullying was associated with poorer psychosocial adjustment (P<.05). In all or nearly all countries, bullies, victims, and bully-victims reported greater health problems and poorer emotional and social adjustment. Victims and bully-victims consistently reported poorer relationships with classmates, whereas bullies and bully-victims reported greater alcohol use and weapon carrying. Conclusions The association of bullying with poorer psychosocial adjustment is remarkably similar across countries. Bullying is a critical issue for the health of youth internationally. PMID:15289243

  17. Analytical derivation: An epistemic game for solving mathematically based physics problems

    NASA Astrophysics Data System (ADS)

    Bajracharya, Rabindra R.; Thompson, John R.

    2016-06-01

    Problem solving, which often involves multiple steps, is an integral part of physics learning and teaching. Using the perspective of the epistemic game, we documented a specific game that is commonly pursued by students while solving mathematically based physics problems: the analytical derivation game. This game involves deriving an equation through symbolic manipulations and routine mathematical operations, usually without any physical interpretation of the processes. This game often creates cognitive obstacles in students, preventing them from using alternative resources or better approaches during problem solving. We conducted hour-long, semi-structured, individual interviews with fourteen introductory physics students. Students were asked to solve four "pseudophysics" problems containing algebraic and graphical representations. The problems required the application of the fundamental theorem of calculus (FTC), which is one of the most frequently used mathematical concepts in physics problem solving. We show that the analytical derivation game is necessary, but not sufficient, to solve mathematically based physics problems, specifically those involving graphical representations.

  18. Linking attentional processes and conceptual problem solving: visual cues facilitate the automaticity of extracting relevant information from diagrams

    PubMed Central

    Rouinfar, Amy; Agra, Elise; Larson, Adam M.; Rebello, N. Sanjay; Loschky, Lester C.

    2014-01-01

    This study investigated links between visual attention processes and conceptual problem solving. This was done by overlaying visual cues on conceptual physics problem diagrams to direct participants’ attention to relevant areas to facilitate problem solving. Participants (N = 80) individually worked through four problem sets, each containing a diagram, while their eye movements were recorded. Each diagram contained regions that were relevant to solving the problem correctly and separate regions related to common incorrect responses. Problem sets contained an initial problem, six isomorphic training problems, and a transfer problem. The cued condition saw visual cues overlaid on the training problems. Participants’ verbal responses were used to determine their accuracy. This study produced two major findings. First, short duration visual cues which draw attention to solution-relevant information and aid in the organizing and integrating of it, facilitate both immediate problem solving and generalization of that ability to new problems. Thus, visual cues can facilitate re-representing a problem and overcoming impasse, enabling a correct solution. Importantly, these cueing effects on problem solving did not involve the solvers’ attention necessarily embodying the solution to the problem, but were instead caused by solvers attending to and integrating relevant information in the problems into a solution path. Second, this study demonstrates that when such cues are used across multiple problems, solvers can automatize the extraction of problem-relevant information extraction. These results suggest that low-level attentional selection processes provide a necessary gateway for relevant information to be used in problem solving, but are generally not sufficient for correct problem solving. Instead, factors that lead a solver to an impasse and to organize and integrate problem information also greatly facilitate arriving at correct solutions. PMID:25324804

  19. Linking attentional processes and conceptual problem solving: visual cues facilitate the automaticity of extracting relevant information from diagrams.

    PubMed

    Rouinfar, Amy; Agra, Elise; Larson, Adam M; Rebello, N Sanjay; Loschky, Lester C

    2014-01-01

    This study investigated links between visual attention processes and conceptual problem solving. This was done by overlaying visual cues on conceptual physics problem diagrams to direct participants' attention to relevant areas to facilitate problem solving. Participants (N = 80) individually worked through four problem sets, each containing a diagram, while their eye movements were recorded. Each diagram contained regions that were relevant to solving the problem correctly and separate regions related to common incorrect responses. Problem sets contained an initial problem, six isomorphic training problems, and a transfer problem. The cued condition saw visual cues overlaid on the training problems. Participants' verbal responses were used to determine their accuracy. This study produced two major findings. First, short duration visual cues which draw attention to solution-relevant information and aid in the organizing and integrating of it, facilitate both immediate problem solving and generalization of that ability to new problems. Thus, visual cues can facilitate re-representing a problem and overcoming impasse, enabling a correct solution. Importantly, these cueing effects on problem solving did not involve the solvers' attention necessarily embodying the solution to the problem, but were instead caused by solvers attending to and integrating relevant information in the problems into a solution path. Second, this study demonstrates that when such cues are used across multiple problems, solvers can automatize the extraction of problem-relevant information extraction. These results suggest that low-level attentional selection processes provide a necessary gateway for relevant information to be used in problem solving, but are generally not sufficient for correct problem solving. Instead, factors that lead a solver to an impasse and to organize and integrate problem information also greatly facilitate arriving at correct solutions.

  20. Methodology for senior-proof guidelines: A practice example from the Netherlands.

    PubMed

    van Munster, Barbara C; Portielje, Johanna E A; Maier, Andrea B; Arends, Arend J; de Beer, Johannes J A

    2018-02-01

    Evidence-based guidelines constitute a foundation for medical decision making. It is often unclear whether recommendations in general guidelines also apply to older people. This study aimed to develop a methodology to increase the focus on older people in the development of guidelines. The methodology distinguishes 4 groups of older people: (1) relatively healthy older people; (2) older people with 1 additional specific (interfering) comorbid condition; (3) older people with multimorbidity; and (4) vulnerable older people. The level of focus on older people required may be determined by the prevalence of the disease or condition, level of suffering, social relevance, and the expectation that a guideline may improve the quality of care. A specialist in geriatric medicine may be involved in the guideline process via participation, provision of feedback on drafts, or involvement in the analysis of problem areas. Regarding the patient perspective, it is advised to involve organisations for older people or informal carers in the inventory of problem areas, and additionally to perform literature research of patient values on the subject. If the guideline focuses on older people, then the relative importance of the various outcome measures for this target group needs to be explicitly stated. Search strategies for all the 4 groups are suggested. For clinical studies that focus on the treatment of diseases that frequently occur in older people, a check should be made regarding whether these studies produce the required evidence. This can be achieved by verifying if there is sufficient representation of older people in the studies and determining if there is a separate reporting of results applying to this age group. © 2017 John Wiley & Sons, Ltd.

  1. Involvement of stakeholders in determining health priorities of adolescents in rural South Africa.

    PubMed

    Twine, Rhian; Kahn, Kathleen; Scholtz, Alexandra; Norris, Shane A

    2016-01-01

    When developing intervention research, it is important to explore issues from the community perspective. Interventions that promote adolescent health in South Africa are urgently needed, and Project Ntshembo ('hope') aims to improve the health of young women and their offspring in the Agincourt sub-district of rural northeast South Africa, actively using stakeholder involvement throughout the research process. This study aimed to determine adolescent health priorities according to key stakeholders, to align stakeholder and researcher priorities, and to form a stakeholder forum, which would be active throughout the intervention. Thirty-two stakeholders were purposefully identified as community members interested in the health of adolescents. An adapted Delphi incorporating face-to-face discussions, as well as participatory visualisation, was used in a series of three workshops. Consensus was determined through non-parametric analysis. Stakeholders and researchers agreed that peer pressure and lack of information, or having information but not acting on it, were the root causes of adolescent health problems. Pregnancy, HIV, school dropout, alcohol and drug abuse, not accessing health services, and unhealthy lifestyle (leading to obesity) were identified as priority adolescent health issues. A diagram was developed showing how these eight priorities relate to one another, which was useful in the development of the intervention. A stakeholder forum was founded, comprising 12 of the stakeholders involved in the stakeholder involvement process. The process brought researchers and stakeholders to consensus on the most important health issues facing adolescents, and a stakeholder forum was developed within which to address the issues. Stakeholder involvement as part of a research engagement strategy can be of mutual benefit to the researchers and the community in which the research is taking place.

  2. Optimal Control Inventory Stochastic With Production Deteriorating

    NASA Astrophysics Data System (ADS)

    Affandi, Pardi

    2018-01-01

    In this paper, we are using optimal control approach to determine the optimal rate in production. Most of the inventory production models deal with a single item. First build the mathematical models inventory stochastic, in this model we also assume that the items are in the same store. The mathematical model of the problem inventory can be deterministic and stochastic models. In this research will be discussed how to model the stochastic as well as how to solve the inventory model using optimal control techniques. The main tool in the study problems for the necessary optimality conditions in the form of the Pontryagin maximum principle involves the Hamilton function. So we can have the optimal production rate in a production inventory system where items are subject deterioration.

  3. Projectile motion without calculus

    NASA Astrophysics Data System (ADS)

    Rizcallah, Joseph A.

    2018-07-01

    Projectile motion is a constant theme in introductory-physics courses. It is often used to illustrate the application of differential and integral calculus. While most of the problems used for this purpose, such as maximizing the range, are kept at a fairly elementary level, some, such as determining the safe domain, involve not so elementary techniques, which can hardly be assumed of the targeted audience. In the literature, several attempts have been undertaken to avoid calculus altogether and keep the exposition entirely within the realm of algebra and/or geometry. In this paper, we propose yet another non-calculus approach which uses the projectile’s travel times to shed new light on these problems and provide instructors with an alternate method to address them with their students.

  4. A Revision on Classical Solutions to the Cauchy Boltzmann Problem for Soft Potentials

    NASA Astrophysics Data System (ADS)

    Alonso, Ricardo J.; Gamba, Irene M.

    2011-05-01

    This short note complements the recent paper of the authors (Alonso, Gamba in J. Stat. Phys. 137(5-6):1147-1165, 2009). We revisit the results on propagation of regularity and stability using L p estimates for the gain and loss collision operators which had the exponent range misstated for the loss operator. We show here the correct range of exponents. We require a Lebesgue's exponent α>1 in the angular part of the collision kernel in order to obtain finiteness in some constants involved in the regularity and stability estimates. As a consequence the L p regularity associated to the Cauchy problem of the space inhomogeneous Boltzmann equation holds for a finite range of p≥1 explicitly determined.

  5. A statistical theory for sound radiation and reflection from a duct

    NASA Technical Reports Server (NTRS)

    Cho, Y. C.

    1979-01-01

    A new analytical method is introduced for the study of the sound radiation and reflection from the open end of a duct. The sound is thought of as an aggregation of the quasiparticles-phonons. The motion of the latter is described in terms of the statistical distribution, which is derived from the classical wave theory. The results are in good agreement with the solutions obtained using the Wiener-Hopf technique when the latter is applicable, but the new method is simple and provides straightforward physical interpretation of the problem. Furthermore, it is applicable to a problem involving a duct in which modes are difficult to determine or cannot be defined at all, whereas the Wiener-Hopf technique is not.

  6. Practicality of electronic beam steering for MST/ST radars, part 6.2A

    NASA Technical Reports Server (NTRS)

    Clark, W. L.; Green, J. L.

    1984-01-01

    Electronic beam steering is described as complex and expensive. The Sunset implementation of electronic steering is described, and it is demonstrated that such systems are cost effective, versatile, and no more complex than fixed beam alternatives, provided three or more beams are needed. The problem of determining accurate meteorological wind components in the presence of spatial variation is considered. A cost comparison of steerable and fixed systems allowing solution of this problem is given. The concepts and relations involved in phase steering are given, followed by the description of the Sunset ST radar steering system. The implications are discussed, references to the competing SAD method are provided, and a recommendation concerning the design of the future Doppler ST/MST systems is made.

  7. Effect of Scaffolding on Helping Introductory Physics Students Solve Quantitative Problems Involving Strong 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…

  8. Analytical Derivation: An Epistemic Game for Solving Mathematically Based Physics Problems

    ERIC Educational Resources Information Center

    Bajracharya, Rabindra R.; Thompson, John R.

    2016-01-01

    Problem solving, which often involves multiple steps, is an integral part of physics learning and teaching. Using the perspective of the epistemic game, we documented a specific game that is commonly pursued by students while solving mathematically based physics problems: the "analytical derivation" game. This game involves deriving an…

  9. Involvement in the Juvenile Justice System for African American Adolescents: Examining Associations with Behavioral Health Problems

    PubMed Central

    Voisin, Dexter R.; Kim, Dongha; Takahashi, Lois; Morotta, Phillip; Bocanegra, Kathryn

    2017-01-01

    While researchers have found that African American youth experience higher levels of juvenile justice involvement at every system level (arrest, sentencing, and incarceration) relative to their other ethnic counterparts, few studies have explored how juvenile justice involvement and number of contacts might be correlated with this broad range of problems. A convenience sample of 638 African American adolescents living in predominantly low-income, urban communities participated in a survey related to juvenile justice involvement. Major findings using logistic regression models indicated that adolescents who reported juvenile justice system involvement versus no involvement were 2.3 times as likely to report mental health problems, substance abuse, and delinquent or youth offending behaviors. Additional findings documented that the higher the number of juvenile justice system contacts, the higher the rates of delinquent behaviors, alcohol and marijuana use, sex while high on drugs, and commercial sex. These findings suggest that identifying and targeting youth who have multiple juvenile justice system contacts, especially those in low-resourced communities for early intervention services, may be beneficial. Future research should examine whether peer network norms might mediate the relationships between juvenile justice involvement and youth problem behaviors. PMID:28966415

  10. Involvement in the Juvenile Justice System for African American Adolescents: Examining Associations with Behavioral Health Problems.

    PubMed

    Voisin, Dexter R; Kim, Dongha; Takahashi, Lois; Morotta, Phillip; Bocanegra, Kathryn

    2017-01-01

    While researchers have found that African American youth experience higher levels of juvenile justice involvement at every system level (arrest, sentencing, and incarceration) relative to their other ethnic counterparts, few studies have explored how juvenile justice involvement and number of contacts might be correlated with this broad range of problems. A convenience sample of 638 African American adolescents living in predominantly low-income, urban communities participated in a survey related to juvenile justice involvement. Major findings using logistic regression models indicated that adolescents who reported juvenile justice system involvement versus no involvement were 2.3 times as likely to report mental health problems, substance abuse, and delinquent or youth offending behaviors. Additional findings documented that the higher the number of juvenile justice system contacts, the higher the rates of delinquent behaviors, alcohol and marijuana use, sex while high on drugs, and commercial sex. These findings suggest that identifying and targeting youth who have multiple juvenile justice system contacts, especially those in low-resourced communities for early intervention services, may be beneficial. Future research should examine whether peer network norms might mediate the relationships between juvenile justice involvement and youth problem behaviors.

  11. Pressure-Volume Work Exercises Illustrating the First and Second Laws.

    ERIC Educational Resources Information Center

    Hoover, William G.; Moran, Bill

    1979-01-01

    Presented are two problem exercises involving rapid compression and expansion of ideal gases which illustrate the first and second laws of thermodynamics. The first problem involves the conversion of gravitational energy into heat through mechanical work. The second involves the mutual interaction of two gases through an adiabatic piston. (BT)

  12. Development of a Larvicidal Nanoemulsion with Pterodon emarginatus Vogel Oil

    PubMed Central

    Oliveira, Anna E. M. F. M.; Duarte, Jonatas L.; Amado, Jesus R. R.; Cruz, Rodrigo A. S.; Rocha, Clarice F.; Souto, Raimundo N. P.; Ferreira, Ricardo M. A.; Santos, Karen; da Conceição, Edemilson C.; de Oliveira, Leandra A. R.; Kelecom, Alphonse; Fernandes, Caio P.; Carvalho, José C. T.

    2016-01-01

    Pterodon emarginatus Vogel is a Brazilian species that belongs to the family Fabaceae, popularly known as sucupira. Its oil has several biological activities, including potent larvicidal property against Aedes aegypti. This insect is the vector of dengue, a tropical disease that has been considered a critical health problem in developing countries, such as Brazil. Most of dengue control methods involve larvicidal agents suspended or diluted in water and making active lipophilic natural products available is therefore considered a technological challenge. In this context, nanoemulsions appear as viable alternatives to solve this major problem. The present study describes the development of a novel nanoemulsion with larvicidal activity against A. aegypti along with the required Hydrophile Lipophile Balance determination of this oil. It was suggested that the mechanism of action might involve reversible inhibition of acetylcholinesterase and our results also suggest that the P. emarginatus nanoemulsion is not toxic for mammals. Thus, it contributes significantly to alternative integrative practices of dengue control, as well as to develop sucupira based nanoproducts for application in aqueous media. PMID:26742099

  13. Serotonin toxicity involving MDMA (ecstasy) and moclobemide.

    PubMed

    Pilgrim, J L; Gerostamoulos, D; Woodford, N; Drummer, Olaf H

    2012-02-10

    The use of MDMA (ecstasy) in Australia is a widespread and growing problem, promoting acute toxicity and disease which can lead to premature death in users. We report four cases of fatal serotonin toxicity caused by the combination of MDMA and moclobemide, a reversible MAO-A inhibitor with potent serotonergic activity. Despite the highly reported toxicity of this drug combination, there are very few reports of fatalities attributed to a MDMA and moclobemide interaction. Pathology and toxicology reports, initial police reports and coroners' findings were examined to determine the circumstances of the deaths. Symptoms of some of the four cases as reported by paramedics and medical staff included hyperthermia, hyperkalemia, profuse sweating, twitching and shaking. Two cases involved moclobemide concentrations consistent with common prescribed doses, while the other two cases involved much higher concentrations often associated with toxicity. Three of these cases presented with some form of heart disease. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  14. Latent profile analysis of teacher perceptions of parent contact and comfort.

    PubMed

    Stormont, Melissa; Herman, Keith C; Reinke, Wendy M; David, Kimberly B; Goel, Nidhi

    2013-09-01

    The purpose of the study was to explore patterns of parent involvement as perceived by teachers and identify correlates of these patterns. Parent involvement indicators and correlates were selected from a review of existing research. Participants included 34 teachers and 577 children in kindergarten through third grade. The vast majority of the sample was African American (78%), followed by Caucasian (19%) and other ethnic backgrounds (2%). Two subscales from the Parent Involvement-Teacher scale, contact and comfort, were entered as indicators in a latent profile analysis to determine the number and types of parent involvement classes. Contact included the frequency of interactions between parents and teachers; comfort included the quality of their relationship with the parent and how well their goals were aligned. Subsequent latent class regressions were conducted to identify student, school, and family characteristics associated with class membership. Three classes provided the optimal solution. This included two classes of parents with low contact with teachers but different comfort levels; one with low contact and low comfort (11%), and one with low contact but high comfort (71%). The remaining class, representing 18% of parents, was rated high on both contact and comfort. Low income status, family problems, and social, emotional, academic, and self-regulation problems distinguished the low comfort class from the other two classes. It is imperative to help teachers feel more comfortable working with families who may be experiencing substantial stressors and who also have children who need support across school and home settings.

  15. Involvement in Childrearing and Firm Control Parenting by Male Cohabiting Partners in Black Low-income Stepfamilies: Forecasting Adolescent Problem Behaviors

    PubMed Central

    Forehand, Rex; Parent, Justin; Golub, Andrew; Reid, Megan; Lafko, Nicole

    2018-01-01

    Cohabitation is a family structure that is rapidly increasing in the United States. The current longitudinal study examined the interplay of involvement in a youth’s daily activities and firm control parenting by male cohabiting partners (MCPs) on change in adolescents’ internalizing and externalizing problems. In a sample of 111 inner-city African American families, adolescents reported on involvement and parenting by MCPs at wave 1 and biological mothers reported on adolescent problem behaviors at waves 1 and 2. A significant interaction indicated that low involvement and low firm control by MCPs at wave 1 were associated with the highest level of internalizing problems at wave 2. An interaction did not emerge when externalizing problems served as the outcome. The findings indicate that male partners play an important role in parenting adolescents in cohabiting families and should be considered as potential participants in prevention and intervention programs. PMID:26007695

  16. Forensic facial approximation: an overview of current methods used at the Victorian Institute of Forensic Medicine/Victoria Police Criminal Identification Squad.

    PubMed

    Hayes, S; Taylor, R; Paterson, A

    2005-12-01

    Forensic facial approximation involves building a likeness of the head and face on the skull of an unidentified individual, with the aim that public broadcast of the likeness will trigger recognition in those who knew the person in life. This paper presents an overview of the collaborative practice between Ronn Taylor (Forensic Sculptor to the Victorian Institute of Forensic Medicine) and Detective Sergeant Adrian Paterson (Victoria Police Criminal Identification Squad). This collaboration involves clay modelling to determine an approximation of the person's head shape and feature location, with surface texture and more speculative elements being rendered digitally onto an image of the model. The advantages of this approach are that through clay modelling anatomical contouring is present, digital enhancement resolves some of the problems of visual perception of a representation, such as edge and shape determination, and the approximation can be easily modified as and when new information is received.

  17. Medical errors arising from outsourcing laboratory and radiology services.

    PubMed

    Chasin, Brian S; Elliott, Sean P; Klotz, Stephen A

    2007-09-01

    Document errors and the nuisance factor inherent in the informational exchange that occurs with the outsourcing of laboratory and radiology examinations. Three infectious diseases physicians at a tertiary care hospital recorded problems involving data transmitted by telephone or fax from outsource providers for 4 months. This included in- and outpatients, and those in transition from one status to another. Outsourcing laboratory and radiology examinations of insured outpatients is a common practice. Insurance companies determine which healthcare facility performs these tests based on contractual agreements with outsource providers. This leads to confusion and frustration for the doctor and patient alike, and occasionally, to medical error. The exchange of patient data involved in outsourcing is subject to systemic errors that do not allow of easy solution.

  18. Determination of thermoelastic material properties by differential heterodyne detection of impulsive stimulated thermal scattering

    PubMed Central

    Verstraeten, B.; Sermeus, J.; Salenbien, R.; Fivez, J.; Shkerdin, G.; Glorieux, C.

    2015-01-01

    The underlying working principle of detecting impulsive stimulated scattering signals in a differential configuration of heterodyne diffraction detection is unraveled by involving optical scattering theory. The feasibility of the method for the thermoelastic characterization of coating-substrate systems is demonstrated on the basis of simulated data containing typical levels of noise. Besides the classical analysis of the photoacoustic part of the signals, which involves fitting surface acoustic wave dispersion curves, the photothermal part of the signals is analyzed by introducing thermal wave dispersion curves to represent and interpret their grating wavelength dependence. The intrinsic possibilities and limitations of both inverse problems are quantified by making use of least and most squares analysis. PMID:26236643

  19. The conception, birth, and growth of a missile umbilical system

    NASA Technical Reports Server (NTRS)

    Nordman, G. W.

    1977-01-01

    The design development was traced for the sprint 2 and improved sprint 2 missile system (ISMS) umbilical system. The unique system requirements, umbilical designs considered to meet the requirements, and the problems encountered and solutions derived during the design, and development testing of the selected systems are described. The sprint 2 development effort consisted of design, analysis, and testing activities. The ISMS effort involved the performance of an extensive trade study to determine the optimum design to meet the ISMS conditions.

  20. Long-term care information systems: an overview of the selection process.

    PubMed

    Nahm, Eun-Shim; Mills, Mary Etta; Feege, Barbara

    2006-06-01

    Under the current Medicare Prospective Payment System method and the ever-changing managed care environment, the long-term care information system is vital to providing quality care and to surviving in business. system selection process should be an interdisciplinary effort involving all necessary stakeholders for the proposed system. The system selection process can be modeled following the Systems Developmental Life Cycle: identifying problems, opportunities, and objectives; determining information requirements; analyzing system needs; designing the recommended system; and developing and documenting software.

  1. Developing Breast Cancer Program at Xavier; Genomic and Proteomic Analysis of Signaling Pathways Involved in Xenohormone and MEK5 Regulation of Breast

    DTIC Science & Technology

    2008-05-01

    will build a core of human talent that will address scientific problems such as drug resistance and the effect of environmental agents on breast...normal for Xavier University after the continuing effects of Hurricane Katrina. Xavier University of Louisiana did an amazing recovery from the...an increase in expression of ERβ . To determine the effects of MEK5 on ER signaling we used an ERE-luciferase reporter assay. Parental MCF-7 cells

  2. Thermal convection in a cylindrical enclosure

    NASA Astrophysics Data System (ADS)

    Shukla, K. N.

    2005-02-01

    The paper highlights the onset of convection in a fluid layer partially filled in an axisymmetric container. The equilibrium of the fluid is disturbed with the deformation of the interface due to residual acceleration. The general problem of deformable interface involves a dimensionless parameter, the Bond number. An analytical expression for the natural frequencies of the deformable surface is derived in terms of the Bond number, which determines the time period required for the stable location of the fluid for the propellant management of the spacecraft.

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

    Newman, J.R.; Maltby, J.H.

    The purpose of this presentation was to discuss the emerging role of financial entities in determining environmental requirements for international power projects. The paper outlines the following: emerging conditions; examples of announced privatization energy projects by country; types of government and international financial entity sources; problems for IPPs; similarity and differences between the World Bank and the USEPA; comparison of the international standards and regulations for power plants; recent trends/issues involving international power project approval; and recommendations for understanding/expediting the financial entities` environmental approval process and how to expedite this process.

  4. Examining Masculinity Norms, Problem Drinking, and Athletic Involvement as Predictors of Sexual Aggression in College Men

    ERIC Educational Resources Information Center

    Locke, Benjamin D.; Mahalik, James R.

    2005-01-01

    Male sexual aggression toward women is a serious social problem, particularly on college campuses. In this study, college men's sexually aggressive behavior and rape myth acceptance were examined using conformity to 11 masculine norms and 2 variables previously linked to sexual aggression: problem drinking and athletic involvement. Results…

  5. Family Involvement in Preschool Education: Rationale, Problems and Solutions for the Participants

    ERIC Educational Resources Information Center

    Kocyigit, Sinan

    2015-01-01

    This aim of this study is to examine the views of teachers, administrators and parents about the problems that emerge during family involvement in preschool activities and solutions for these problems. The participants were 10 teachers, 10 parents and 10 administrators from 4 preschools and 6 kindergartens in the Palandöken and Yakutiye districts…

  6. A method for the selection of a functional form for a thermodynamic equation of state using weighted linear least squares stepwise regression

    NASA Technical Reports Server (NTRS)

    Jacobsen, R. T.; Stewart, R. B.; Crain, R. W., Jr.; Rose, G. L.; Myers, A. F.

    1976-01-01

    A method was developed for establishing a rational choice of the terms to be included in an equation of state with a large number of adjustable coefficients. The methods presented were developed for use in the determination of an equation of state for oxygen and nitrogen. However, a general application of the methods is possible in studies involving the determination of an optimum polynomial equation for fitting a large number of data points. The data considered in the least squares problem are experimental thermodynamic pressure-density-temperature data. Attention is given to a description of stepwise multiple regression and the use of stepwise regression in the determination of an equation of state for oxygen and nitrogen.

  7. Parent Involvement and Children's Academic and Social Development in Elementary School

    PubMed Central

    El Nokali, Nermeen E.; Bachman, Heather J.; Votruba-Drzal, Elizabeth

    2010-01-01

    Data from the NICHD Study of Early Childcare and Youth Development (N= 1364) were used to investigate children's trajectories of academic and social development across first, third and fifth grade. Hierarchical linear modeling was used to examine within- and between-child associations among maternal- and teacher-reports of parent involvement and children's standardized achievement scores, social skills, and problem behaviors. Findings suggest that within-child improvements in parent involvement predict declines in problem behaviors and improvements in social skills but do not predict changes in achievement. Between-child analyses demonstrated that children with highly involved parents had enhanced social functioning and fewer behavior problems. Similar patterns of findings emerged for teacher- and parent-reports of parent involvement. Implications for policy and practice are discussed. PMID:20573118

  8. The dynamic network subserving the three phases of cognitive procedural learning.

    PubMed

    Hubert, Valérie; Beaunieux, Hélène; Chételat, Gaël; Platel, Hervé; Landeau, Brigitte; Danion, Jean-Marie; Viader, Fausto; Desgranges, Béatrice

    2007-12-01

    Cognitive procedural learning is characterized by three phases (cognitive, associative, and autonomous), each involving distinct processes. We performed a behavioral study and a positron emission tomography (PET) activation study using the Tower of Toronto task. The aim of the behavioral study was to determine cognitive predictors for the length of each of the three learning phases, in order to preselect subjects for the PET study. The objective of the second study was to describe the cerebral substrates subtending these three phases. Contrasted with a reference (motor) task, the cognitive phase activated the prefrontal cortex, cerebellum, and parietal regions, all of which became less active as learning progressed. The associative phase was characterized by the activation of the occipital regions, right thalamus, and caudate nucleus. During the autonomous phase, new regions were involved, including the left thalamus and an anterior part of the cerebellum. These results, by employing a direct comparison between phases, provide the first evidence of the involvement and the time course of activation of different regions in each learning phase, in accordance with current models of cognitive procedural learning. The involvement of a frontoparietal network suggests the use of strategies in problem solving during the cognitive phase. The involvement of the occipital regions during the associative and autonomous phase suggests the intervention of mental imagery. Lastly, the activation of the cerebellum during the autonomous phase is consistent with the fact that performance in this phase is determined by psychomotor abilities. (copyright) 2007 Wiley-Liss, Inc.

  9. Problem Solving Process Research of Everyone Involved in Innovation Based on CAI Technology

    NASA Astrophysics Data System (ADS)

    Chen, Tao; Shao, Yunfei; Tang, Xiaowo

    It is very important that non-technical department personnel especially bottom line employee serve as innovators under the requirements of everyone involved in innovation. According the view of this paper, it is feasible and necessary to build everyone involved in innovation problem solving process under Total Innovation Management (TIM) based on the Theory of Inventive Problem Solving (TRIZ). The tools under the CAI technology: How TO mode and science effects database could be very useful for all employee especially non-technical department and bottom line for innovation. The problem solving process put forward in the paper focus on non-technical department personnel especially bottom line employee for innovation.

  10. Teachers' perceptions of remediation possibilities of Dutch students in special education.

    PubMed

    Bakker, Joep T A; Bosman, Anna M T

    2006-12-01

    Research suggests that referral practices of teachers in regular education are not only affected by the level of learning difficulties but also by student behaviour and the level of students' parental involvement in education. It was hypothesized that teachers maintain a notion of the 'ideal' student, who has relatively good academic skills, is well behaved and has highly involved parents. The main question of this study was whether special-education teachers' perceptions regarding remediation possibilities are similarly affected by student behaviour and the level of students' parental involvement. Nineteen experienced Dutch school teachers in special education each evaluated four students: two with relatively high and two with relatively low academic performance. Three questionnaires to assess learning difficulties, behavioural problems and the level of parental involvement were developed. Teachers' perceptions of remediation possibilities were related to the severity of the learning difficulties and academic skill. Academic skill, in turn, was strongly related to the perception of the children's behavioural problems and parental involvement, which, in turn, links the perception of remediation possibilities indirectly to children's behavioural problems and parental involvement. Special education teachers may also hold an image of the 'ideal' student. Students with high academic achievement levels are perceived as having fewer behavioural problems and more highly involved parents than students with low academic achievement levels. Whether this is due to justified or unjustified teachers' perceptions is a matter for future research. What is important is that stereotyping of students (justly or not) poses a serious problem for the Dutch reintegration policy.

  11. Analytic solution of the Spencer-Lewis angular-spatial moments equations

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

    Filippone, W.L.

    A closed-form solution for the angular-spatial moments of the Spencer-Lewis equation is presented that is valid for infinite homogeneous media. From the moments, the electron density distribution as a function of position and path length (energy) is reconstructed for several sample problems involving plane isotropic sources of electrons in aluminium. The results are in excellent agreement with those determined numerically using the streaming ray method. The primary use of the closed form solution will most likely be to generate accurate electron transport benchmark solutions. In principle, the electron density as a function of space, path length, and direction can bemore » determined for planar sources of arbitrary angular distribution.« less

  12. Drinking characteristics of drivers arrested for driving while intoxicated in two police jurisdictions.

    PubMed

    Fell, James C; Tippetts, Scott; Voas, Robert

    2010-10-01

    Are drivers arrested for driving while intoxicated (DWI) most likely to be the drinking drivers who are involved in fatal and serious injury crashes? This study determined the drinking characteristics of drivers arrested for DWI or driving under the influence (DUI) and the proportion classified as problem drinkers and hardcore drinking drivers in two police jurisdictions. In addition to determining the drinking characteristics of DWI arrestees, the results were compared to the drinking characteristics of intoxicated drivers killed in traffic crashes. Police officers gathered data at the time of arrest from 1027 drivers apprehended for DWI or DUI in the two communities on their alcohol consumption, their drinking-and-driving frequency, their self-reported alcohol problems, their place of drinking and types of drinks before the arrest, and their perceptions of impaired-driving enforcement intensity. Data analyses indicated that 52 percent of the arrested DWI offenders were considered problem drinkers, 46 percent were repeat offenders, 57 percent were classified as hardcore drinking drivers, 51 percent were drinking at a bar or restaurant before their arrest, and 72 percent were drinking beer before their arrest. Compared to highly intoxicated (blood alcohol concentration [BAC] ≥.15) drivers killed in traffic crashes, the high-BAC arrestees were substantially more likely to be problem drinkers and to report drinking and driving more often. The limited resources available for combating impaired driving should not be solely allocated to problem drinkers, hardcore drinkers, or repeat offenders because, at most, they constitute only about half of the impaired-driving problem in the United States. General deterrent strategies have the best chance of impacting the total population of at-risk drinking drivers.

  13. Cyberbullying, depression, and problem alcohol use in female college students: a multisite study.

    PubMed

    Selkie, Ellen M; Kota, Rajitha; Chan, Ya-Fen; Moreno, Megan

    2015-02-01

    Cyberbullying and its effects have been studied largely in middle and high school students, but less is known about cyberbullying in college students. This cross-sectional study investigated the relationship between involvement in cyberbullying and depression or problem alcohol use among college females. Two hundred and sixty-five female students from four colleges completed online surveys assessing involvement in cyberbullying behaviors. Participants also completed the Patient Health Questionnaire-9 (PHQ-9) to assess depressive symptoms and the Alcohol Use Disorder Identification Test (AUDIT) to assess problem drinking. Logistic regression tested associations between involvement in cyberbullying and either depression or problem drinking. Results indicated that 27% of participants had experienced cyberbullying in college; 17.4% of all participants met the criteria for depression (PHQ-9 score ≥10), and 37.5% met the criteria for problem drinking (AUDIT score ≥8). Participants with any involvement in cyberbullying had increased odds of depression. Those involved in cyberbullying as bullies had increased odds of both depression and problem alcohol use. Bully/victims had increased odds of depression. The four most common cyberbullying behaviors were also associated with increased odds for depression, with the highest odds among those who had experienced unwanted sexual advances online or via text message. Findings indicate that future longitudinal study of cyberbullying and its effects into late adolescence and young adulthood could contribute to the prevention of associated comorbidities in this population.

  14. Maternal Depressive Symptoms and Child Behavior Problems among Latina Adolescent Mothers: The Buffering Effect of Mother-Reported Partner Child Care Involvement

    ERIC Educational Resources Information Center

    Smith, Erin N.; Grau, Josefina M.; Duran, Petra A.; Castellanos, Patricia

    2013-01-01

    We examined the relations between maternal depressive symptoms and child internalizing and externalizing problems in a sample of 125 adolescent Latina mothers (primarily Puerto Rican) and their toddlers. We also tested the influence of mother-reported partner child care involvement on child behavior problems and explored mother-reported partner…

  15. Frequent methamphetamine injection predicts emergency department utilization among street-involved youth

    PubMed Central

    Marshall, B.D.L.; Grafstein, E.; Buxton, J.A.; Qi, J.; Wood, E.; Shoveller, J.A.; Kerr, T.

    2011-01-01

    SUMMARY Objectives Methamphetamine (MA) use has been associated with health problems that commonly present in the emergency department (ED). This study sought to determine whether frequent MA injection was a risk factor for ED utilization among street-involved youth. Study design Prospective cohort study. Methods Data were derived from a street-involved youth cohort known as the ‘At Risk Youth Study’. Behavioural data including MA use were linked to ED records at a major inner-city hospital. Kaplan-Meier and Cox proportional hazards methods were used to determine the risk factors for ED utilization. Results Between September 2005 and January 2007, 427 eligible participants were enrolled, among whom the median age was 21 (interquartile range 19–23) years and 154 (36.1%) were female. Within 1 year, 163 (38.2%) visited the ED, resulting in an incidence density of 53.7 per 100 person-years. ED utilization was significantly higher among frequent (i.e. ≥daily) MA injectors (log-rank P=0.004). In multivariate analysis, frequent MA injection was associated with an increased hazard of ED utilization (adjusted hazard ratio=1.84, 95% confidence interval 1.04–3.25; P=0.036). Conclusions Street-involved youth who frequently inject MA appear to be at increased risk of ED utilization. The integration of MA-specific addiction treatment services within emergency care settings for high-risk youth is recommended. PMID:22133669

  16. Facilitating problem solving in high school chemistry

    NASA Astrophysics Data System (ADS)

    Gabel, Dorothy L.; Sherwood, Robert D.

    The major purpose for conducting this study was to determine whether certain instructional strategies were superior to others in teaching high school chemistry students problem solving. The effectiveness of four instructional strategies for teaching problem solving to students of various proportional reasoning ability, verbal and visual preference, and mathematics anxiety were compared in this aptitude by treatment interaction study. The strategies used were the factor-label method, analogies, diagrams, and proportionality. Six hundred and nine high school students in eight schools were randomly assigned to one of four teaching strategies within each classroom. Students used programmed booklets to study the mole concept, the gas laws, stoichiometry, and molarity. Problem-solving ability was measured by a series of immediate posttests, delayed posttests and the ACS-NSTA Examination in High School Chemistry. Results showed that mathematics anxiety is negatively correlated with science achievement and that problem solving is dependent on students' proportional reasoning ability. The factor-label method was found to be the most desirable method and proportionality the least desirable method for teaching the mole concept. However, the proportionality method was best for teaching the gas laws. Several second-order interactions were found to be significant when mathematics anxiety was one of the aptitudes involved.

  17. Relational complexity modulates activity in the prefrontal cortex during numerical inductive reasoning: an fMRI study.

    PubMed

    Feng, Xiao; Peng, Li; Chang-Quan, Long; Yi, Lei; Hong, Li

    2014-09-01

    Most previous studies investigating relational reasoning have used visuo-spatial materials. This fMRI study aimed to determine how relational complexity affects brain activity during inductive reasoning, using numerical materials. Three numerical relational levels of the number series completion task were adopted for use: 0-relational (e.g., "23 23 23"), 1-relational ("32 30 28") and 2-relational ("12 13 15") problems. The fMRI results revealed that the bilateral dorsolateral prefrontal cortex (DLPFC) showed enhanced activity associated with relational complexity. Bilateral inferior parietal lobule (IPL) activity was greater during the 1- and 2-relational level problems than during the 0-relational level problems. In addition, the left fronto-polar cortex (FPC) showed selective activity during the 2-relational level problems. The bilateral DLPFC may be involved in the process of hypothesis generation, whereas the bilateral IPL may be sensitive to calculation demands. Moreover, the sensitivity of the left FPC to the multiple relational problems may be related to the integration of numerical relations. The present study extends our knowledge of the prefrontal activity pattern underlying numerical relational processing. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Principal Component Geostatistical Approach for large-dimensional inverse problems

    PubMed Central

    Kitanidis, P K; Lee, J

    2014-01-01

    The quasi-linear geostatistical approach is for weakly nonlinear underdetermined inverse problems, such as Hydraulic Tomography and Electrical Resistivity Tomography. It provides best estimates as well as measures for uncertainty quantification. However, for its textbook implementation, the approach involves iterations, to reach an optimum, and requires the determination of the Jacobian matrix, i.e., the derivative of the observation function with respect to the unknown. Although there are elegant methods for the determination of the Jacobian, the cost is high when the number of unknowns, m, and the number of observations, n, is high. It is also wasteful to compute the Jacobian for points away from the optimum. Irrespective of the issue of computing derivatives, the computational cost of implementing the method is generally of the order of m2n, though there are methods to reduce the computational cost. In this work, we present an implementation that utilizes a matrix free in terms of the Jacobian matrix Gauss-Newton method and improves the scalability of the geostatistical inverse problem. For each iteration, it is required to perform K runs of the forward problem, where K is not just much smaller than m but can be smaller that n. The computational and storage cost of implementation of the inverse procedure scales roughly linearly with m instead of m2 as in the textbook approach. For problems of very large m, this implementation constitutes a dramatic reduction in computational cost compared to the textbook approach. Results illustrate the validity of the approach and provide insight in the conditions under which this method perform best. PMID:25558113

  19. Principal Component Geostatistical Approach for large-dimensional inverse problems.

    PubMed

    Kitanidis, P K; Lee, J

    2014-07-01

    The quasi-linear geostatistical approach is for weakly nonlinear underdetermined inverse problems, such as Hydraulic Tomography and Electrical Resistivity Tomography. It provides best estimates as well as measures for uncertainty quantification. However, for its textbook implementation, the approach involves iterations, to reach an optimum, and requires the determination of the Jacobian matrix, i.e., the derivative of the observation function with respect to the unknown. Although there are elegant methods for the determination of the Jacobian, the cost is high when the number of unknowns, m , and the number of observations, n , is high. It is also wasteful to compute the Jacobian for points away from the optimum. Irrespective of the issue of computing derivatives, the computational cost of implementing the method is generally of the order of m 2 n , though there are methods to reduce the computational cost. In this work, we present an implementation that utilizes a matrix free in terms of the Jacobian matrix Gauss-Newton method and improves the scalability of the geostatistical inverse problem. For each iteration, it is required to perform K runs of the forward problem, where K is not just much smaller than m but can be smaller that n . The computational and storage cost of implementation of the inverse procedure scales roughly linearly with m instead of m 2 as in the textbook approach. For problems of very large m , this implementation constitutes a dramatic reduction in computational cost compared to the textbook approach. Results illustrate the validity of the approach and provide insight in the conditions under which this method perform best.

  20. Dynamic Flow Management Problems in Air Transportation

    NASA Technical Reports Server (NTRS)

    Patterson, Sarah Stock

    1997-01-01

    In 1995, over six hundred thousand licensed pilots flew nearly thirty-five million flights into over eighteen thousand U.S. airports, logging more than 519 billion passenger miles. Since demand for air travel has increased by more than 50% in the last decade while capacity has stagnated, congestion is a problem of undeniable practical significance. In this thesis, we will develop optimization techniques that reduce the impact of congestion on the national airspace. We start by determining the optimal release times for flights into the airspace and the optimal speed adjustment while airborne taking into account the capacitated airspace. This is called the Air Traffic Flow Management Problem (TFMP). We address the complexity, showing that it is NP-hard. We build an integer programming formulation that is quite strong as some of the proposed inequalities are facet defining for the convex hull of solutions. For practical problems, the solutions of the LP relaxation of the TFMP are very often integral. In essence, we reduce the problem to efficiently solving large scale linear programming problems. Thus, the computation times are reasonably small for large scale, practical problems involving thousands of flights. Next, we address the problem of determining how to reroute aircraft in the airspace system when faced with dynamically changing weather conditions. This is called the Air Traffic Flow Management Rerouting Problem (TFMRP) We present an integrated mathematical programming approach for the TFMRP, which utilizes several methodologies, in order to minimize delay costs. In order to address the high dimensionality, we present an aggregate model, in which we formulate the TFMRP as a multicommodity, integer, dynamic network flow problem with certain side constraints. Using Lagrangian relaxation, we generate aggregate flows that are decomposed into a collection of flight paths using a randomized rounding heuristic. This collection of paths is used in a packing integer programming formulation, the solution of which generates feasible and near-optimal routes for individual flights. The algorithm, termed the Lagrangian Generation Algorithm, is used to solve practical problems in the southwestern portion of United States in which the solutions are within 1% of the corresponding lower bounds.

  1. Model Order Reduction for the fast solution of 3D Stokes problems and its application in geophysical inversion

    NASA Astrophysics Data System (ADS)

    Ortega Gelabert, Olga; Zlotnik, Sergio; Afonso, Juan Carlos; Díez, Pedro

    2017-04-01

    The determination of the present-day physical state of the thermal and compositional structure of the Earth's lithosphere and sub-lithospheric mantle is one of the main goals in modern lithospheric research. All this data is essential to build Earth's evolution models and to reproduce many geophysical observables (e.g. elevation, gravity anomalies, travel time data, heat flow, etc) together with understanding the relationship between them. Determining the lithospheric state involves the solution of high-resolution inverse problems and, consequently, the solution of many direct models is required. The main objective of this work is to contribute to the existing inversion techniques in terms of improving the estimation of the elevation (topography) by including a dynamic component arising from sub-lithospheric mantle flow. In order to do so, we implement an efficient Reduced Order Method (ROM) built upon classic Finite Elements. ROM allows to reduce significantly the computational cost of solving a family of problems, for example all the direct models that are required in the solution of the inverse problem. The strategy of the method consists in creating a (reduced) basis of solutions, so that when a new problem has to be solved, its solution is sought within the basis instead of attempting to solve the problem itself. In order to check the Reduced Basis approach, we implemented the method in a 3D domain reproducing a portion of Earth that covers up to 400 km depth. Within the domain the Stokes equation is solved with realistic viscosities and densities. The different realizations (the family of problems) is created by varying viscosities and densities in a similar way as it would happen in an inversion problem. The Reduced Basis method is shown to be an extremely efficiently solver for the Stokes equation in this context.

  2. Learning comunication strategies for distributed artificial intelligence

    NASA Astrophysics Data System (ADS)

    Kinney, Michael; Tsatsoulis, Costas

    1992-08-01

    We present a methodology that allows collections of intelligent system to automatically learn communication strategies, so that they can exchange information and coordinate their problem solving activity. In our methodology communication between agents is determined by the agents themselves, which consider the progress of their individual problem solving activities compared to the communication needs of their surrounding agents. Through learning, communication lines between agents might be established or disconnected, communication frequencies modified, and the system can also react to dynamic changes in the environment that might force agents to cease to exist or to be added. We have established dynamic, quantitative measures of the usefulness of a fact, the cost of a fact, the work load of an agent, and the selfishness of an agent (a measure indicating an agent's preference between transmitting information versus performing individual problem solving), and use these values to adapt the communication between intelligent agents. In this paper we present the theoretical foundations of our work together with experimental results and performance statistics of networks of agents involved in cooperative problem solving activities.

  3. Development of Proportional Reasoning: Where Young Children Go Wrong

    PubMed Central

    Boyer, Ty W.; Levine, Susan C.; Huttenlocher, Janellen

    2008-01-01

    Previous studies have found that children have difficulty solving proportional reasoning problems involving discrete units until 10- to 12-years of age, but can solve parallel problems involving continuous quantities by 6-years of age. The present studies examine where children go wrong in processing proportions that involve discrete quantities. A computerized proportional equivalence choice task was administered to kindergartners through fourth-graders in Study 1, and to first- and third-graders in Study 2. Both studies involved four between-subjects conditions that were formed by pairing continuous and discrete target proportions with continuous and discrete choice alternatives. In Study 1, target and choice alternatives were presented simultaneously and in Study 2 target and choice alternatives were presented sequentially. In both studies, children performed significantly worse when both the target and choice alternatives were represented with discrete quantities than when either or both of the proportions involved continuous quantities. Taken together, these findings indicate that children go astray on proportional reasoning problems involving discrete units only when a numerical match is possible, suggesting that their difficulty is due to an overextension of numerical equivalence concepts to proportional equivalence problems. PMID:18793078

  4. Children's mental health and family functioning in Rhode Island.

    PubMed

    Kim, Hyun Hanna K; Viner-Brown, Samara I; Garcia, Jorge

    2007-02-01

    Our objectives were to (a) estimate the prevalence of children's mental health problems, (b) assess family functioning, and (c) investigate the relationship between children's mental health and family functioning in Rhode Island. From the 2003 National Survey of Children's Health, Rhode Island data for children 6 to 17 years of age were used for the analyses (N = 1326). Two aspects of family functioning measures, parental stress and parental involvement, were constructed and were examined by children's mental health problems, as well as other child and family characteristics (child's age, gender, race/ethnicity, special needs, parent's education, income, employment, family structure, number of children, and mother's general and mental health). Bivariate analyses and multivariate logistic regression were used to investigate the relationship. Among Rhode Island children, nearly 1 (19.0%) in 5 had mental health problems, 1 (15.6%) in 6 lived with a highly stressed parent, and one third (32.7%) had parents with low involvement. Bivariate analyses showed that high parental stress and low parental involvement were higher among parents of children with mental health problems than parents of children without those problems (33.2% vs 11.0% and 41.0% vs 30.3%, respectively). In multivariate logistic regression, parents of children with mental health problems had nearly 4 times the odds of high stress compared with parents of children without those problems. When children's mental health problems were severe, the odds of high parental stress were elevated. However, children's mental health was not associated with parental involvement. Children's mental health was strongly associated with parental stress, but it was not associated with parental involvement. The findings indicate that when examining the mental health issues of children, parental mental health and stress must be considered.

  5. A numerical study of different projection-based model reduction techniques applied to computational homogenisation

    NASA Astrophysics Data System (ADS)

    Soldner, Dominic; Brands, Benjamin; Zabihyan, Reza; Steinmann, Paul; Mergheim, Julia

    2017-10-01

    Computing the macroscopic material response of a continuum body commonly involves the formulation of a phenomenological constitutive model. However, the response is mainly influenced by the heterogeneous microstructure. Computational homogenisation can be used to determine the constitutive behaviour on the macro-scale by solving a boundary value problem at the micro-scale for every so-called macroscopic material point within a nested solution scheme. Hence, this procedure requires the repeated solution of similar microscopic boundary value problems. To reduce the computational cost, model order reduction techniques can be applied. An important aspect thereby is the robustness of the obtained reduced model. Within this study reduced-order modelling (ROM) for the geometrically nonlinear case using hyperelastic materials is applied for the boundary value problem on the micro-scale. This involves the Proper Orthogonal Decomposition (POD) for the primary unknown and hyper-reduction methods for the arising nonlinearity. Therein three methods for hyper-reduction, differing in how the nonlinearity is approximated and the subsequent projection, are compared in terms of accuracy and robustness. Introducing interpolation or Gappy-POD based approximations may not preserve the symmetry of the system tangent, rendering the widely used Galerkin projection sub-optimal. Hence, a different projection related to a Gauss-Newton scheme (Gauss-Newton with Approximated Tensors- GNAT) is favoured to obtain an optimal projection and a robust reduced model.

  6. Decision support system for the operating room rescheduling problem.

    PubMed

    van Essen, J Theresia; Hurink, Johann L; Hartholt, Woutske; van den Akker, Bernd J

    2012-12-01

    Due to surgery duration variability and arrivals of emergency surgeries, the planned Operating Room (OR) schedule is disrupted throughout the day which may lead to a change in the start time of the elective surgeries. These changes may result in undesirable situations for patients, wards or other involved departments, and therefore, the OR schedule has to be adjusted. In this paper, we develop a decision support system (DSS) which assists the OR manager in this decision by providing the three best adjusted OR schedules. The system considers the preferences of all involved stakeholders and only evaluates the OR schedules that satisfy the imposed resource constraints. The decision rules used for this system are based on a thorough analysis of the OR rescheduling problem. We model this problem as an Integer Linear Program (ILP) which objective is to minimize the deviation from the preferences of the considered stakeholders. By applying this ILP to instances from practice, we determined that the given preferences mainly lead to (i) shifting a surgery and (ii) scheduling a break between two surgeries. By using these changes in the DSS, the performed simulation study shows that less surgeries are canceled and patients and wards are more satisfied, but also that the perceived workload of several departments increases to compensate this. The system can also be used to judge the acceptability of a proposed initial OR schedule.

  7. Initiating heavy-atom-based phasing by multi-dimensional molecular replacement.

    PubMed

    Pedersen, Bjørn Panyella; Gourdon, Pontus; Liu, Xiangyu; Karlsen, Jesper Lykkegaard; Nissen, Poul

    2016-03-01

    To obtain an electron-density map from a macromolecular crystal the phase problem needs to be solved, which often involves the use of heavy-atom derivative crystals and concomitant heavy-atom substructure determination. This is typically performed by dual-space methods, direct methods or Patterson-based approaches, which however may fail when only poorly diffracting derivative crystals are available. This is often the case for, for example, membrane proteins. Here, an approach for heavy-atom site identification based on a molecular-replacement parameter matrix (MRPM) is presented. It involves an n-dimensional search to test a wide spectrum of molecular-replacement parameters, such as different data sets and search models with different conformations. Results are scored by the ability to identify heavy-atom positions from anomalous difference Fourier maps. The strategy was successfully applied in the determination of a membrane-protein structure, the copper-transporting P-type ATPase CopA, when other methods had failed to determine the heavy-atom substructure. MRPM is well suited to proteins undergoing large conformational changes where multiple search models should be considered, and it enables the identification of weak but correct molecular-replacement solutions with maximum contrast to prime experimental phasing efforts.

  8. Initiating heavy-atom-based phasing by multi-dimensional molecular replacement

    PubMed Central

    Pedersen, Bjørn Panyella; Gourdon, Pontus; Liu, Xiangyu; Karlsen, Jesper Lykkegaard; Nissen, Poul

    2016-01-01

    To obtain an electron-density map from a macromolecular crystal the phase problem needs to be solved, which often involves the use of heavy-atom derivative crystals and concomitant heavy-atom substructure determination. This is typically performed by dual-space methods, direct methods or Patterson-based approaches, which however may fail when only poorly diffracting derivative crystals are available. This is often the case for, for example, membrane proteins. Here, an approach for heavy-atom site identification based on a molecular-replacement parameter matrix (MRPM) is presented. It involves an n-dimensional search to test a wide spectrum of molecular-replacement parameters, such as different data sets and search models with different conformations. Results are scored by the ability to identify heavy-atom positions from anomalous difference Fourier maps. The strategy was successfully applied in the determination of a membrane-protein structure, the copper-transporting P-type ATPase CopA, when other methods had failed to determine the heavy-atom substructure. MRPM is well suited to proteins undergoing large conformational changes where multiple search models should be considered, and it enables the identification of weak but correct molecular-replacement solutions with maximum contrast to prime experimental phasing efforts. PMID:26960131

  9. Integrating Problem-Based Learning and Simulation: Effects on Student Motivation and Life Skills.

    PubMed

    Roh, Young Sook; Kim, Sang Suk

    2015-07-01

    Previous research has suggested that a teaching strategy integrating problem-based learning and simulation may be superior to traditional lecture. The purpose of this study was to assess learner motivation and life skills before and after taking a course involving problem-based learning and simulation. The design used repeated measures with a convenience sample of 83 second-year nursing students who completed the integrated course. Data from a self-administered questionnaire measuring learner motivation and life skills were collected at pretest, post-problem-based learning, and post-simulation time points. Repeated-measures analysis of variance determined that the mean scores for total learner motivation (F=6.62, P=.003), communication (F=8.27, P<.001), problem solving (F=6.91, P=.001), and self-directed learning (F=4.45, P=.016) differed significantly between time points. Post hoc tests using the Bonferroni correction revealed that total learner motivation and total life skills significantly increased both from pretest to postsimulation and from post-problem-based learning test to postsimulation test. Subscales of learner motivation and life skills, intrinsic goal orientation, self-efficacy for learning and performance, problem-solving skills, and self-directed learning skills significantly increased both from pretest to postsimulation test and from post-problem-based learning test to post-simulation test. The results demonstrate that an integrating problem-based learning and simulation course elicits significant improvement in learner motivation and life skills. Simulation plus problem-based learning is more effective than problem-based learning alone at increasing intrinsic goal orientation, task value, self-efficacy for learning and performance, problem solving, and self-directed learning.

  10. Control and stabilization of decentralized systems

    NASA Technical Reports Server (NTRS)

    Byrnes, Christopher I.; Gilliam, David; Martin, Clyde F.

    1989-01-01

    Proceeding from the problem posed by the need to stabilize the motion of two helicopters maneuvering a single load, a methodology is developed for the stabilization of classes of decentralized systems based on a more algebraic approach, which involves the external symmetries of decentralized systems. Stabilizing local-feedback laws are derived for any class of decentralized systems having a semisimple algebra of symmetries; the helicopter twin-lift problem, as well as certain problems involving the stabilization of discretizations of distributed parameter problems, have just such algebras of symmetries.

  11. Identification of Novel Virulence Determinants in Mycobacterium paratuberculosis by Screening a Library of Insertional Mutants†

    PubMed Central

    Shin, Sung Jae; Wu, Chia-wei; Steinberg, Howard; Talaat, Adel M.

    2006-01-01

    Johne's disease, caused by Mycobacterium paratuberculosis infection, is a worldwide problem for the dairy industry and has a possible involvement in Crohn's disease in humans. To identify virulence determinants of this economically important pathogen, a library of 5,060 transposon mutants was constructed using Tn5367 insertion mutagenesis, followed by large-scale sequencing to identify disrupted genes. In this report, 1,150 mutants were analyzed and 970 unique insertion sites were identified. Sequence analysis of the disrupted genes indicated that the insertion of Tn5367 was more prevalent in genomic regions with G+C content (50.5 to 60.5%) lower than the average G+C content (69.3%) of the rest of the genome. Phenotypic screening of the library identified disruptions of genes involved in iron, tryptophan, or mycolic acid metabolic pathways that displayed unique growth characteristics. Bioinformatic analysis of disrupted genes identified a list of potential virulence determinants for further testing with animals. Mouse infection studies showed a significant decrease in tissue colonization by mutants with a disruption in the gcpE, pstA, kdpC, papA2, impA, umaA1, or fabG2_2 gene. Attenuation phenotypes were tissue specific (e.g., for the umaA1 mutant) as well as time specific (e.g., for the impA mutant), suggesting that those genes may be involved in different virulence mechanisms. The identified potential virulence determinants represent novel functional classes that could be necessary for mycobacterial survival during infection and could provide suitable targets for vaccine and drug development against Johne's and Crohn's diseases. PMID:16790754

  12. ["How goes it, Awa?" Nutritional deficiency, emotional deprivation, severe depressive state in an child under 2 years of age. Diagnostic and therapeutic problems].

    PubMed

    Buffet, Y; Mazet, P

    1983-12-15

    The authors report a very illustrative case of analytic depression in an infant under two years of age. The significance of this observation is in the overwhelming nature of symptoms with a characteristic marasmus syndrome fitting classic descriptions, and in the deliberate approach which led a pedo-psychiatric team to an understanding of the problems and to a rapid and dramatic reparation. By the ascription of a significant role to the impact of mother-child, mother-family and social circle relationships, involved members were able to determine their place and reassume their role and function. This approach also draws attention to the susceptibility and vulnerability of children to separation and severance of bonds.

  13. On the classification of elliptic foliations induced by real quadratic fields with center

    NASA Astrophysics Data System (ADS)

    Puchuri, Liliana; Bueno, Orestes

    2016-12-01

    Related to the study of Hilbert's infinitesimal problem, is the problem of determining the existence and estimating the number of limit cycles of the linear perturbation of Hamiltonian fields. A classification of the elliptic foliations in the projective plane induced by the fields obtained by quadratic fields with center was already studied by several authors. In this work, we devise a unified proof of the classification of elliptic foliations induced by quadratic fields with center. This technique involves using a formula due to Cerveau & Lins Neto to calculate the genus of the generic fiber of a first integral of foliations of these kinds. Furthermore, we show that these foliations induce several examples of linear families of foliations which are not bimeromorphically equivalent to certain remarkable examples given by Lins Neto.

  14. An Approach to Management of Gas in the Elderly

    PubMed Central

    Hogan, David B.

    1989-01-01

    In this article I shall review the physiology, clinical manifestations, and management of gaseousness in the elderly. While not an infrequent complaint, little scientific study has been done of the causes or management of this problem. The regualtion of bowel gas is surprisingly complex. When problems occur, it is usually either because of excessive swallowing of air or because of the intraluminal producation of gas by colonic bacteria. Patients present with excessive belching, abdominal pain and bloating, or excessive passage of flatus. Management is determined, in the main, by the results of the history and physical examination. Medications are usually not indicated. Once a malabsorptive state is ruled out, the mainstay of management usually involves either alterations in the patient's diet or avoidance of aerophagia. PMID:21249002

  15. Efficient searching in meshfree methods

    NASA Astrophysics Data System (ADS)

    Olliff, James; Alford, Brad; Simkins, Daniel C.

    2018-04-01

    Meshfree methods such as the Reproducing Kernel Particle Method and the Element Free Galerkin method have proven to be excellent choices for problems involving complex geometry, evolving topology, and large deformation, owing to their ability to model the problem domain without the constraints imposed on the Finite Element Method (FEM) meshes. However, meshfree methods have an added computational cost over FEM that come from at least two sources: increased cost of shape function evaluation and the determination of adjacency or connectivity. The focus of this paper is to formally address the types of adjacency information that arises in various uses of meshfree methods; a discussion of available techniques for computing the various adjacency graphs; propose a new search algorithm and data structure; and finally compare the memory and run time performance of the methods.

  16. Distributed photovoltaic systems: Utility interface issues and their present status

    NASA Technical Reports Server (NTRS)

    Hassan, M.; Klein, J.

    1981-01-01

    Major technical issues involving the integration of distributed photovoltaics (PV) into electric utility systems are defined and their impacts are described quantitatively. An extensive literature search, interviews, and analysis yielded information about the work in progress and highlighted problem areas in which additional work and research are needed. The findings from the literature search were used to determine whether satisfactory solutions to the problems exist or whether satisfactory approaches to a solution are underway. It was discovered that very few standards, specifications, or guidelines currently exist that will aid industry in integrating PV into the utility system. Specific areas of concern identified are: (1) protection, (2) stability, (3) system unbalance, (4) voltage regulation and reactive power requirements, (5) harmonics, (6) utility operations, (7) safety, (8) metering, and (9) distribution system planning and design.

  17. Effective Documentation Tools

    NASA Technical Reports Server (NTRS)

    Sleboda, Claire

    1997-01-01

    Quality assurance programs provide a very effective means to monitor and evaluate medical care. Quality assurance involves: (1) Identify a problem; (2) Determine the source and nature of the problem; (3) Develop policies and methods to effect improvement; (4) Implement those polices; (5) Monitor the methods applied; and (6) Evaluate their effectiveness. Because this definition of quality assurance so closely resembles the Nursing Process, the health unit staff was able to use their knowledge of the nursing process to develop many forms which improve the quality of patient care. These forms include the NASA DFRC Service Report, the occupational injury form (Incident Report), the patient survey (Pre-hospital Evaluation/Care Report), the Laboratory Log Sheet, the 911 Run Sheet, and the Patient Assessment Stamp. Examples and steps which are followed to generate these reports are described.

  18. Accomplishing the Visions for Teacher Education Programs Advocated in the National Science Education Standards

    NASA Astrophysics Data System (ADS)

    Akcay, Hakan; Yager, Robert

    2010-10-01

    The purpose of this study was to investigate the advantages of an approach to instruction using current problems and issues as curriculum organizers and illustrating how teaching must change to accomplish real learning. The study sample consisted of 41 preservice science teachers (13 males and 28 females) in a model science teacher education program. Both qualitative and quantitative research methods were used to determine success with science discipline-specific “Societal and Educational Applications” courses as one part of a total science teacher education program at a large Midwestern university. Students were involved with idea generation, consideration of multiple points of views, collaborative inquiries, and problem solving. All of these factors promoted grounded instruction using constructivist perspectives that situated science with actual experiences in the lives of students.

  19. Sound field reproduction as an equivalent acoustical scattering problem.

    PubMed

    Fazi, Filippo Maria; Nelson, Philip A

    2013-11-01

    Given a continuous distribution of acoustic sources, the determination of the source strength that ensures the synthesis of a desired sound field is shown to be identical to the solution of an equivalent acoustic scattering problem. The paper begins with the presentation of the general theory that underpins sound field reproduction with secondary sources continuously arranged on the boundary of the reproduction region. The process of reproduction by a continuous source distribution is modeled by means of an integral operator (the single layer potential). It is then shown how the solution of the sound reproduction problem corresponds to that of an equivalent scattering problem. Analytical solutions are computed for two specific instances of this problem, involving, respectively, the use of a secondary source distribution in spherical and planar geometries. The results are shown to be the same as those obtained with analyses based on High Order Ambisonics and Wave Field Synthesis, respectively, thus bringing to light a fundamental analogy between these two methods of sound reproduction. Finally, it is shown how the physical optics (Kirchhoff) approximation enables the derivation of a high-frequency simplification for the problem under consideration, this in turn being related to the secondary source selection criterion reported in the literature on Wave Field Synthesis.

  20. Visuospatial anatomy comprehension: the role of spatial visualization ability and problem-solving strategies.

    PubMed

    Nguyen, Ngan; Mulla, Ali; Nelson, Andrew J; Wilson, Timothy D

    2014-01-01

    The present study explored the problem-solving strategies of high- and low-spatial visualization ability learners on a novel spatial anatomy task to determine whether differences in strategies contribute to differences in task performance. The results of this study provide further insights into the processing commonalities and differences among learners beyond the classification of spatial visualization ability alone, and help elucidate what, if anything, high- and low-spatial visualization ability learners do differently while solving spatial anatomy task problems. Forty-two students completed a standardized measure of spatial visualization ability, a novel spatial anatomy task, and a questionnaire involving personal self-analysis of the processes and strategies used while performing the spatial anatomy task. Strategy reports revealed that there were different ways students approached answering the spatial anatomy task problems. However, chi-square test analyses established that differences in problem-solving strategies did not contribute to differences in task performance. Therefore, underlying spatial visualization ability is the main source of variation in spatial anatomy task performance, irrespective of strategy. In addition to scoring higher and spending less time on the anatomy task, participants with high spatial visualization ability were also more accurate when solving the task problems. © 2013 American Association of Anatomists.

  1. Patient involvement in mental health care: one size does not fit all

    PubMed Central

    Tambuyzer, Else; Pieters, Guido; Van Audenhove, Chantal

    2014-01-01

    Abstract Background  Involvement of mental health‐care patients in the decision‐making processes is considered to be an ethical requirement. Health‐care systems worldwide are increasingly emphasizing the value of participatory approaches. There is, however, no consensus on the definition of patient involvement. The literature is particularly inconsistent and lacks clarity. Objective  The purpose of this article is to clarify the concept of patient involvement in mental health care (MHC), taking into account its multidimensional nature. Search strategy  We searched the literature in online databases from January 1998 until August 2010 using synonyms of ‘patient involvement’, combined with the terms ‘mental health(care)’. Data synthesis  Based on 45 different descriptions found in the literature, we constructed a definition of patient involvement and we drew up a model identifying its determinants and outcomes. Results  We propose a comprehensive model of patient involvement to be used in MHC. This model can serve as a guide for policy makers and field workers to shape policies to stimulate involvement. Discussion and conclusions  There are three main problems in the literature concerning patient involvement. First, there is a proliferation of conceptualizations of the topic, leading to conceptual vagueness. Furthermore, there is a lack of quantitative data, and some aspects of involvement remain underexposed, such as the involvement of specific target groups and practical ways to shape the involvement processes. Involvement processes should be tailored to the specific target group and context. PMID:22070468

  2. Investigation of practical applications of H infinity control theory to the design of control systems for large space structures

    NASA Technical Reports Server (NTRS)

    Irwin, R. Dennis

    1988-01-01

    The applicability of H infinity control theory to the problems of large space structures (LSS) control was investigated. A complete evaluation to any technique as a candidate for large space structure control involves analytical evaluation, algorithmic evaluation, evaluation via simulation studies, and experimental evaluation. The results of analytical and algorithmic evaluations are documented. The analytical evaluation involves the determination of the appropriateness of the underlying assumptions inherent in the H infinity theory, the determination of the capability of the H infinity theory to achieve the design goals likely to be imposed on an LSS control design, and the identification of any LSS specific simplifications or complications of the theory. The resuls of the analytical evaluation are presented in the form of a tutorial on the subject of H infinity control theory with the LSS control designer in mind. The algorthmic evaluation of H infinity for LSS control pertains to the identification of general, high level algorithms for effecting the application of H infinity to LSS control problems, the identification of specific, numerically reliable algorithms necessary for a computer implementation of the general algorithms, the recommendation of a flexible software system for implementing the H infinity design steps, and ultimately the actual development of the necessary computer codes. Finally, the state of the art in H infinity applications is summarized with a brief outline of the most promising areas of current research.

  3. How to Begin a Quality Improvement Project.

    PubMed

    Silver, Samuel A; Harel, Ziv; McQuillan, Rory; Weizman, Adam V; Thomas, Alison; Chertow, Glenn M; Nesrallah, Gihad; Bell, Chaim M; Chan, Christopher T

    2016-05-06

    Quality improvement involves a combined effort among health care staff and stakeholders to diagnose and treat problems in the health care system. However, health care professionals often lack training in quality improvement methods, which makes it challenging to participate in improvement efforts. This article familiarizes health care professionals with how to begin a quality improvement project. The initial steps involve forming an improvement team that possesses expertise in the quality of care problem, leadership, and change management. Stakeholder mapping and analysis are useful tools at this stage, and these are reviewed to help identify individuals who might have a vested interest in the project. Physician engagement is a particularly important component of project success, and the knowledge that patients/caregivers can offer as members of a quality improvement team should not be overlooked. After a team is formed, an improvement framework helps to organize the scientific process of system change. Common quality improvement frameworks include Six Sigma, Lean, and the Model for Improvement. These models are contrasted, with a focus on the Model for Improvement, because it is widely used and applicable to a variety of quality of care problems without advanced training. It involves three steps: setting aims to focus improvement, choosing a balanced set of measures to determine if improvement occurs, and testing new ideas to change the current process. These new ideas are evaluated using Plan-Do-Study-Act cycles, where knowledge is gained by testing changes and reflecting on their effect. To show the real world utility of the quality improvement methods discussed, they are applied to a hypothetical quality improvement initiative that aims to promote home dialysis (home hemodialysis and peritoneal dialysis). This provides an example that kidney health care professionals can use to begin their own quality improvement projects. Copyright © 2016 by the American Society of Nephrology.

  4. How to Begin a Quality Improvement Project

    PubMed Central

    Harel, Ziv; McQuillan, Rory; Weizman, Adam V.; Thomas, Alison; Chertow, Glenn M.; Nesrallah, Gihad; Bell, Chaim M.; Chan, Christopher T.

    2016-01-01

    Quality improvement involves a combined effort among health care staff and stakeholders to diagnose and treat problems in the health care system. However, health care professionals often lack training in quality improvement methods, which makes it challenging to participate in improvement efforts. This article familiarizes health care professionals with how to begin a quality improvement project. The initial steps involve forming an improvement team that possesses expertise in the quality of care problem, leadership, and change management. Stakeholder mapping and analysis are useful tools at this stage, and these are reviewed to help identify individuals who might have a vested interest in the project. Physician engagement is a particularly important component of project success, and the knowledge that patients/caregivers can offer as members of a quality improvement team should not be overlooked. After a team is formed, an improvement framework helps to organize the scientific process of system change. Common quality improvement frameworks include Six Sigma, Lean, and the Model for Improvement. These models are contrasted, with a focus on the Model for Improvement, because it is widely used and applicable to a variety of quality of care problems without advanced training. It involves three steps: setting aims to focus improvement, choosing a balanced set of measures to determine if improvement occurs, and testing new ideas to change the current process. These new ideas are evaluated using Plan-Do-Study-Act cycles, where knowledge is gained by testing changes and reflecting on their effect. To show the real world utility of the quality improvement methods discussed, they are applied to a hypothetical quality improvement initiative that aims to promote home dialysis (home hemodialysis and peritoneal dialysis). This provides an example that kidney health care professionals can use to begin their own quality improvement projects. PMID:27016497

  5. Treatment of ice cover and other thin elastic layers with the parabolic equation method.

    PubMed

    Collins, Michael D

    2015-03-01

    The parabolic equation method is extended to handle problems involving ice cover and other thin elastic layers. Parabolic equation solutions are based on rational approximations that are designed using accuracy constraints to ensure that the propagating modes are handled properly and stability constrains to ensure that the non-propagating modes are annihilated. The non-propagating modes are especially problematic for problems involving thin elastic layers. It is demonstrated that stable results may be obtained for such problems by using rotated rational approximations [Milinazzo, Zala, and Brooke, J. Acoust. Soc. Am. 101, 760-766 (1997)] and generalizations of these approximations. The approach is applied to problems involving ice cover with variable thickness and sediment layers that taper to zero thickness.

  6. Multigrid Methods for Aerodynamic Problems in Complex Geometries

    NASA Technical Reports Server (NTRS)

    Caughey, David A.

    1995-01-01

    Work has been directed at the development of efficient multigrid methods for the solution of aerodynamic problems involving complex geometries, including the development of computational methods for the solution of both inviscid and viscous transonic flow problems. The emphasis is on problems of complex, three-dimensional geometry. The methods developed are based upon finite-volume approximations to both the Euler and the Reynolds-Averaged Navier-Stokes equations. The methods are developed for use on multi-block grids using diagonalized implicit multigrid methods to achieve computational efficiency. The work is focused upon aerodynamic problems involving complex geometries, including advanced engine inlets.

  7. Energy and the Confused Student V: The Energy/Momentum Approach to Problems Involving Rotating and Deformable Systems

    ERIC Educational Resources Information Center

    Jewett, John W., Jr.

    2008-01-01

    Energy is a critical concept in physics problem-solving, but is often a major source of confusion for students if the presentation is not carefully crafted by the instructor or the textbook. A common approach to problems involving deformable or rotating systems that has been discussed in the literature is to employ the work-kinetic energy theorem…

  8. Children of Divorce

    ERIC Educational Resources Information Center

    Jenkins, Shirley

    1978-01-01

    Considers four areas requiring attention in any attempt to evaluate the needs of children in families involved in divorce actions: economic problems and child support; custody issues and court involvement; emotional problems and therapeutic intervention; and kinship patterns in "step" relationships and the reconstituted family. (BR)

  9. Optimal Sampling to Provide User-Specific Climate Information.

    NASA Astrophysics Data System (ADS)

    Panturat, Suwanna

    The types of weather-related world problems which are of socio-economic importance selected in this study as representative of three different levels of user groups include: (i) a regional problem concerned with air pollution plumes which lead to acid rain in the north eastern United States, (ii) a state-level problem in the form of winter wheat production in Oklahoma, and (iii) an individual-level problem involving reservoir management given errors in rainfall estimation at Lake Ellsworth, upstream from Lawton, Oklahoma. The study is aimed at designing optimal sampling networks which are based on customer value systems and also abstracting from data sets that information which is most cost-effective in reducing the climate-sensitive aspects of a given user problem. Three process models being used in this study to interpret climate variability in terms of the variables of importance to the user comprise: (i) the HEFFTER-SAMSON diffusion model as the climate transfer function for acid rain, (ii) the CERES-MAIZE plant process model for winter wheat production and (iii) the AGEHYD streamflow model selected as "a black box" for reservoir management. A state-of-the-art Non Linear Program (NLP) algorithm for minimizing an objective function is employed to determine the optimal number and location of various sensors. Statistical quantities considered in determining sensor locations including Bayes Risk, the chi-squared value, the probability of the Type I error (alpha) and the probability of the Type II error (beta) and the noncentrality parameter delta^2. Moreover, the number of years required to detect a climate change resulting in a given bushel per acre change in mean wheat production is determined; the number of seasons of observations required to reduce the standard deviation of the error variance of the ambient sulfur dioxide to less than a certain percent of the mean is found; and finally the policy of maintaining pre-storm flood pools at selected levels is examined given information from the optimal sampling network as defined by the study.

  10. Psychological needs, purpose in life, and problem video game playing among Chinese young adults.

    PubMed

    Wu, Anise M S; Lei, Lamis L M; Ku, Lisbeth

    2013-01-01

    The negative impacts of excessive and problematic video game playing on both children and adults are attracting increasing concern. Based on self-determination theory (SDT; Ryan & Deci, 2000), this study hypothesized that the three basic psychological needs of autonomy, competence, and relatedness are positively associated with purpose in life, which in turn acts as a protective factor against problem video game playing among Chinese young adult players. Through a questionnaire survey with a sample of 165 Chinese adults aged between 18 and 30 years (mean age = 22.7 years), we found that perceived autonomy, competence, relatedness, and purpose in life were all negatively correlated with problem game playing. The demographic and psychological factors explained 38% of the variances of problem game playing. Specifically, gender, perceived relatedness, and purpose in life emerged as the three most salient predictors of problem game playing among the Chinese young adults. The mediating role of purpose in life was evidenced and it was found that purpose in life mediated the influences of the psychological needs proposed by SDT on problem game playing. Moreover, young men were significantly more susceptible to problem game playing than their female counterparts. To conclude, psychological needs and purpose in life influenced Chinese young adults' vulnerability to problem game playing directly or indirectly. Intervention programs that encourage social involvement and voluntary work, as well as counseling service that helps clients to search for life purpose, are suggested for intervening in problem game playing among Chinese young adults.

  11. Problem video game playing is related to emotional distress in adolescents.

    PubMed

    Gonzálvez, María T; Espada, José P; Tejeiro, Ricardo

    2017-06-28

    Problem use of video games is an increasing risk behaviour. High exposure of adolescents to video games has been linked to a variety of disorders, but the relationship between problem video game playing and emotional welfare is unknown. The aim of the study is to analyse problem video game playing in a sample of adolescents and to determine whether there are differences between online and offline players, in addition to examining its relationship with anxiety and depressive symptomatology. A sample of adolescents (N = 380) completed self-reports measuring video game use and symptoms of anxiety and depression. We found that 7.4% of females and 30% of males can be considered as playing at problem levels. Online players were almost 12 times more likely to play at high frequency than offline players (χ2 (1, 267) = 72.72, p < .001, OR = 11.63, 95% CI [6.31, 21.43]). Males play more frequently, and play more online (χ2 (1, 267) = 50.85, p < .001, OR = 6.74, 95% CI [3.90, 11.64]), with a clear relationship between problem video game playing and anxiety (r = .24; p < .001). In females, there is a relationship between problem video game playing and depression (r = .19; p < .05). Our findings contribute to a better understanding of the psychological variables involved in problem video game playing. The implementation of strategies is suggested in order to prevent pathological gaming and associated problems.

  12. Derived heuristics-based consistent optimization of material flow in a gold processing plant

    NASA Astrophysics Data System (ADS)

    Myburgh, Christie; Deb, Kalyanmoy

    2018-01-01

    Material flow in a chemical processing plant often follows complicated control laws and involves plant capacity constraints. Importantly, the process involves discrete scenarios which when modelled in a programming format involves if-then-else statements. Therefore, a formulation of an optimization problem of such processes becomes complicated with nonlinear and non-differentiable objective and constraint functions. In handling such problems using classical point-based approaches, users often have to resort to modifications and indirect ways of representing the problem to suit the restrictions associated with classical methods. In a particular gold processing plant optimization problem, these facts are demonstrated by showing results from MATLAB®'s well-known fmincon routine. Thereafter, a customized evolutionary optimization procedure which is capable of handling all complexities offered by the problem is developed. Although the evolutionary approach produced results with comparatively less variance over multiple runs, the performance has been enhanced by introducing derived heuristics associated with the problem. In this article, the development and usage of derived heuristics in a practical problem are presented and their importance in a quick convergence of the overall algorithm is demonstrated.

  13. The problems of relative deprivation: why some societies do better than others.

    PubMed

    Wilkinson, Richard G; Pickett, Kate E

    2007-11-01

    In this paper, we present evidence which suggests that key processes of social status differentiation, affecting health and numerous other social outcomes, take place at the societal level. Understanding them seems likely to involve analyses and comparisons of whole societies. Using income inequality as an indicator and determinant of the scale of socioeconomic stratification in a society, we show that many problems associated with relative deprivation are more prevalent in more unequal societies. We summarise previously published evidence suggesting that this may be true of morbidity and mortality, obesity, teenage birth rates, mental illness, homicide, low trust, low social capital, hostility, and racism. To these we add new analyses which suggest that this is also true of poor educational performance among school children, the proportion of the population imprisoned, drug overdose mortality and low social mobility. That ill health and a wide range of other social problems associated with social status within societies are also more common in more unequal societies, may imply that income inequality is central to the creation of the apparently deep-seated social problems associated with poverty, relative deprivation or low social status. We suggest that the degree of material inequality in a society may not only be central to the social forces involved in national patterns of social stratification, but also that many of the problems related to low social status may be amenable to changes in income distribution. If the prevalence of these problems varies so much from society to society according to differences in income distribution, it suggests that the familiar social gradients in health and other outcomes are unlikely to result from social mobility sorting people merely by prior characteristics. Instead, the picture suggests that their frequency in a population is affected by the scale of social stratification that differs substantially from one society to another.

  14. Parenting Practices and Child Disruptive Behavior Problems in Early Elementary School

    PubMed Central

    Stormshak, Elizabeth A.; Bierman, Karen L.; McMahon, Robert J.; Lengua, Liliana J.

    2009-01-01

    Examined the hypothesis that distinct parenting practices may be associated with type and profile of a child’s disruptive behavior problems (e.g., oppositional, aggressive, hyperactive). Parents of 631 behaviorally disruptive children described the extent to which they experienced warm and involved interactions with their children and the extent to which their discipline strategies were inconsistent and punitive and involved spanking and physical aggression. As expected from a developmental perspective, parenting practices that included punitive interactions were associated with elevated rates of all child disruptive behavior problems. Low levels of warm involvement were particularly characteristic of parents of children who showed elevated levels of oppositional behaviors. Physically aggressive parenting was linked more specifically with child aggression. In general, parenting practices contributed more to the prediction of oppositional and aggressive behavior problems than to hyperactive behavior problems, and parenting influences were fairly consistent across ethnic groups and sex. PMID:10693029

  15. Finite element modeling of electromagnetic fields and waves using NASTRAN

    NASA Technical Reports Server (NTRS)

    Moyer, E. Thomas, Jr.; Schroeder, Erwin

    1989-01-01

    The various formulations of Maxwell's equations are reviewed with emphasis on those formulations which most readily form analogies with Navier's equations. Analogies involving scalar and vector potentials and electric and magnetic field components are presented. Formulations allowing for media with dielectric and conducting properties are emphasized. It is demonstrated that many problems in electromagnetism can be solved using the NASTRAN finite element code. Several fundamental problems involving time harmonic solutions of Maxwell's equations with known analytic solutions are solved using NASTRAN to demonstrate convergence and mesh requirements. Mesh requirements are studied as a function of frequency, conductivity, and dielectric properties. Applications in both low frequency and high frequency are highlighted. The low frequency problems demonstrate the ability to solve problems involving media inhomogeneity and unbounded domains. The high frequency applications demonstrate the ability to handle problems with large boundary to wavelength ratios.

  16. Enhance Low-Achieving Students' Learning Involvement in Taiwan's Higher Education: An Approach via E-Learning with Problem-Based Learning and Self-Regulated Learning

    ERIC Educational Resources Information Center

    Lee, Tsang-Hsiung; Shen, Pei-Di; Tsai, Chia-Wen

    2010-01-01

    This study explored the effects of web-enabled pedagogies on students' involvement in learning. A series of quasi-experiments were conducted to investigate whether students' involvement increases over time if intervened, respectively, by problem-based learning (PBL), self-regulated learning (SRL), and their combinations. Two classes of 102…

  17. Inference of emission rates from multiple sources using Bayesian probability theory.

    PubMed

    Yee, Eugene; Flesch, Thomas K

    2010-03-01

    The determination of atmospheric emission rates from multiple sources using inversion (regularized least-squares or best-fit technique) is known to be very susceptible to measurement and model errors in the problem, rendering the solution unusable. In this paper, a new perspective is offered for this problem: namely, it is argued that the problem should be addressed as one of inference rather than inversion. Towards this objective, Bayesian probability theory is used to estimate the emission rates from multiple sources. The posterior probability distribution for the emission rates is derived, accounting fully for the measurement errors in the concentration data and the model errors in the dispersion model used to interpret the data. The Bayesian inferential methodology for emission rate recovery is validated against real dispersion data, obtained from a field experiment involving various source-sensor geometries (scenarios) consisting of four synthetic area sources and eight concentration sensors. The recovery of discrete emission rates from three different scenarios obtained using Bayesian inference and singular value decomposition inversion are compared and contrasted.

  18. Topics in structural dynamics: Nonlinear unsteady transonic flows and Monte Carlo methods in acoustics

    NASA Technical Reports Server (NTRS)

    Haviland, J. K.

    1974-01-01

    The results are reported of two unrelated studies. The first was an investigation of the formulation of the equations for non-uniform unsteady flows, by perturbation of an irrotational flow to obtain the linear Green's equation. The resulting integral equation was found to contain a kernel which could be expressed as the solution of the adjoint flow equation, a linear equation for small perturbations, but with non-constant coefficients determined by the steady flow conditions. It is believed that the non-uniform flow effects may prove important in transonic flutter, and that in such cases, the use of doublet type solutions of the wave equation would then prove to be erroneous. The second task covered an initial investigation into the use of the Monte Carlo method for solution of acoustical field problems. Computed results are given for a rectangular room problem, and for a problem involving a circular duct with a source located at the closed end.

  19. Doctoral training in behavior analysis: Training generalized problem-solving skills

    PubMed Central

    Chase, Philip N.; Wylie, Ruth G.

    1985-01-01

    This essay provides guidelines for designing a doctoral program in behavior analysis. First, we propose a general accomplishment for all behavior analytic doctoral students: that they be able to solve problems concerning individual behavior within a range of environments. Second, in order to achieve this goal, we propose that students be trained in conceptual and experimental analysis of behavior, the application of behavioral principles and the administration of behavioral programs. This training should include class work, but it should emphasize the immersion of students in a variety of environments in which they are required to use behavior analytic strategies. Third, we provide an example of a hypothetical graduate program that involves the proposed training. Finally, an evaluation plan is suggested for determining whether a training program is in fact producing students who are generalized problem-solvers. At each step, we justify our point of view from a perspective that combines principles from behavior analysis and educational systems design. PMID:22478633

  20. Lymphoid cell kinetics under continuous low dose-rate gamma irradiation: A comparison study

    NASA Technical Reports Server (NTRS)

    Foster, B. R.

    1975-01-01

    A comparison study was conducted of the effects of continuous low dose-rate gamma irradiation on cell population kinetics of lymphoid tissue (white pulp) of the mouse spleen with findings as they relate to the mouse thymus. Experimental techniques employed included autoradiography and specific labeling with tritiated thymidine (TdR-(h-3)). The problem studied involved the mechanism of cell proliferation of lymphoid tissue of the mouse spleen and thymus under the stress of continuous irradiation at a dose rate of 10 roentgens (R) per day for 105 days (15 weeks). The aim was to determine whether or not a steady state or near-steady state of cell population could be established for this period of time, and what compensatory mechanisms of cell population were involved.

  1. An analysis of whether a working-age ward-based liaison psychiatry service requires the input of a liaison psychiatrist.

    PubMed

    Guthrie, Elspeth A; McMeekin, Aaron T; Khan, Sylvia; Makin, Sally; Shaw, Ben; Longson, Damien

    2017-06-01

    Aims and method This article presents a 12-month case series to determine the fraction of ward referrals of adults of working age who needed a liaison psychiatrist in a busy tertiary referral teaching hospital. Results The service received 344 referrals resulting in 1259 face-to-face contacts. Depression accounted for the most face-to-face contacts. We deemed the involvement of a liaison psychiatrist necessary in 241 (70.1%) referrals, with medication management as the most common reason. Clinical implications A substantial amount of liaison ward work involves the treatment and management of severe and complex mental health problems. Our analysis suggests that in the majority of cases the input of a liaison psychiatrist is required.

  2. Cyberbullying, Depression, and Problem Alcohol Use in Female College Students: A Multisite Study

    PubMed Central

    Kota, Rajitha; Chan, Ya-Fen; Moreno, Megan

    2015-01-01

    Abstract Cyberbullying and its effects have been studied largely in middle and high school students, but less is known about cyberbullying in college students. This cross-sectional study investigated the relationship between involvement in cyberbullying and depression or problem alcohol use among college females. Two hundred and sixty-five female students from four colleges completed online surveys assessing involvement in cyberbullying behaviors. Participants also completed the Patient Health Questionnaire-9 (PHQ-9) to assess depressive symptoms and the Alcohol Use Disorder Identification Test (AUDIT) to assess problem drinking. Logistic regression tested associations between involvement in cyberbullying and either depression or problem drinking. Results indicated that 27% of participants had experienced cyberbullying in college; 17.4% of all participants met the criteria for depression (PHQ-9 score ≥10), and 37.5% met the criteria for problem drinking (AUDIT score ≥8). Participants with any involvement in cyberbullying had increased odds of depression. Those involved in cyberbullying as bullies had increased odds of both depression and problem alcohol use. Bully/victims had increased odds of depression. The four most common cyberbullying behaviors were also associated with increased odds for depression, with the highest odds among those who had experienced unwanted sexual advances online or via text message. Findings indicate that future longitudinal study of cyberbullying and its effects into late adolescence and young adulthood could contribute to the prevention of associated comorbidities in this population. PMID:25684608

  3. Difference equation state approximations for nonlinear hereditary control problems

    NASA Technical Reports Server (NTRS)

    Rosen, I. G.

    1982-01-01

    Discrete approximation schemes for the solution of nonlinear hereditary control problems are constructed. The methods involve approximation by a sequence of optimal control problems in which the original infinite dimensional state equation has been approximated by a finite dimensional discrete difference equation. Convergence of the state approximations is argued using linear semigroup theory and is then used to demonstrate that solutions to the approximating optimal control problems in some sense approximate solutions to the original control problem. Two schemes, one based upon piecewise constant approximation, and the other involving spline functions are discussed. Numerical results are presented, analyzed and used to compare the schemes to other available approximation methods for the solution of hereditary control problems.

  4. Musculoskeletal problems in Parkinson's disease: neglected issues.

    PubMed

    Kim, Young Eun; Lee, Woong-Woo; Yun, Ji Young; Yang, Hui June; Kim, Han-Joon; Jeon, Beom S

    2013-07-01

    To identify the prevalence and clinical features of musculoskeletal problems in patients with Parkinson disease (PD) compared to controls. 400 PD patients and 138 age- and sex-matched controls were interviewed by physicians about their musculoskeletal problems. The prevalence of musculoskeletal problems was significantly higher in the PD group than in the control group (66.3% vs. 45.7%, P < 0.001). Commonly involved body sites were the low back, knee, and shoulder in that order. The low back was more frequently involved in the PD group than in the control group (44.3% vs. 24.6%, P < 0.001), and the shoulder tended to be more involved in the PD group than in the control group (15.0% vs. 8.7%, P = 0.061). However, the knee was similarly involved in both group (12.3% vs. 18.0%, P = 0.121). Among the past diagnoses associated with musculoskeletal problems, frozen shoulder, low back pain, osteoporosis and fracture were more common in the PD group than in the control group (P < 0.05). Older age, female, and a higher score on the Unified Parkinson's Disease Rating Scale I & II were associated with musculoskeletal problems in the PD group. Only 26.8% of the PD patients and 52.5% of the controls with musculoskeletal problems answered that their musculoskeletal problems were recovering. Furthermore, musculoskeletal problems in the PD group tended to receive less treatment than that of the control group (P = 0.052). Musculoskeletal problems were more common in the PD group than in the controls. Furthermore, despite PD patients having a higher prevalence, they did not receive adequate treatment. Copyright © 2013 Elsevier Ltd. All rights reserved.

  5. Coordinate transformation by minimizing correlations between parameters

    NASA Technical Reports Server (NTRS)

    Kumar, M.

    1972-01-01

    This investigation was to determine the transformation parameters (three rotations, three translations and a scale factor) between two Cartesian coordinate systems from sets of coordinates given in both systems. The objective was the determination of well separated transformation parameters with reduced correlations between each other, a problem especially relevant when the sets of coordinates are not well distributed. The above objective is achieved by preliminarily determining the three rotational parameters and the scale factor from the respective direction cosines and chord distances (these being independent of the translation parameters) between the common points, and then computing all the seven parameters from a solution in which the rotations and the scale factor are entered as weighted constraints according to their variances and covariances obtained in the preliminary solutions. Numerical tests involving two geodetic reference systems were performed to evaluate the effectiveness of this approach.

  6. Fine-scale traverses in cumulate rocks, Stillwater Complex: A lunar analogue study

    NASA Technical Reports Server (NTRS)

    Elthon, Donald

    1988-01-01

    The objective was to document finite-scale compositional variations in cumulate rocks from the Stillwater Complex in Montana and to interpret these data in the context of planetary magma fractionation processes such as those operative during the formation of the Earth's Moon. This research problem involved collecting samples in the Stillwater Complex and analyzing them by electron microprobe, X-ray fluorescence (XRF), and instrumental neutron activation analysis (INAA). The electron microprobe is used to determine the compositions of cumulus and intercumulus phases in the rocks, the XRF is used to determine the bulk-rock major element and trace element (Y, Sr, Rb, Zr, Ni, and Cr) abundances, and the INAA lab. is used to determine the trace element (Sc, Co, Cr, Ni, Ta, Hf, U, Th, and the REE) abundances of mineral separates and bulk rocks.

  7. MosaicSolver: a tool for determining recombinants of viral genomes from pileup data

    PubMed Central

    Wood, Graham R.; Ryabov, Eugene V.; Fannon, Jessica M.; Moore, Jonathan D.; Evans, David J.; Burroughs, Nigel

    2014-01-01

    Viral recombination is a key evolutionary mechanism, aiding escape from host immunity, contributing to changes in tropism and possibly assisting transmission across species barriers. The ability to determine whether recombination has occurred and to locate associated specific recombination junctions is thus of major importance in understanding emerging diseases and pathogenesis. This paper describes a method for determining recombinant mosaics (and their proportions) originating from two parent genomes, using high-throughput sequence data. The method involves setting the problem geometrically and the use of appropriately constrained quadratic programming. Recombinants of the honeybee deformed wing virus and the Varroa destructor virus-1 are inferred to illustrate the method from both siRNAs and reads sampling the viral genome population (cDNA library); our results are confirmed experimentally. Matlab software (MosaicSolver) is available. PMID:25120266

  8. Approach to bullying and victimization.

    PubMed

    Lamb, Jennifer; Pepler, Debra J; Craig, Wendy

    2009-04-01

    To review the epidemiology, identification, and management of bullying and victimization among children in the primary care setting. Information was obtained from PsycINFO and MEDLINE databases, as well as the authors' own clinical and research experience. Information is based on levels II and III evidence. Involvement in bullying is a destructive relationship problem, with important health implications. Physicians need to be aware of the physical and psychosocial symptoms commonly associated with involvement in bullying so that they can screen and identify those children involved. This article presents a review of bullying and associated symptoms, a tool for assessing bullying involvement, and an overview of intervention and management. Bullying is a substantial problem affecting Canadian children. With an increased awareness and understanding of bullying as a health problem, physicians can play an instrumental role in identifying children involved in bullying and providing them with the support needed to develop healthy relationships.

  9. One Answer to "What Is Calculus?"

    ERIC Educational Resources Information Center

    Shilgalis, Thomas W.

    1979-01-01

    A number of questions are posed that can be answered with the aid of calculus. These include best value problems, best shape problems, problems involving integration, and growth and decay problems. (MP)

  10. Strategies for improving the collection of 24-hour urine for analysis in the clinical laboratory: redesigned instructions, opinion surveys, and application of reference change value to micturition.

    PubMed

    Tormo, Consuelo; Lumbreras, Blanca; Santos, Ana; Romero, Luis; Conca, Minerva

    2009-12-01

    -The preanalytic phase of 24-hour urine collection, before clinical analysis, requires the active participation of patients and usually takes place outside the laboratory. -We verify whether distribution of adequate information to health care personnel and patients will result in fewer preanalytic incidents. We also determine the intraindividual biologic variability associated with micturition and the corresponding reference change value (RCV). -The intervention provided training for 24-hour urine collection to the health care personnel of the 20th health district of the Valencian community in Spain. The preanalytic incidents related to 24-hour micturition were estimated before and after the intervention. An opinion survey on the problems involved in urine collection was also conducted among patients. The Harris formula was used to calculate the RCV. -Before the intervention, 130 preanalytic incidents were recorded (11.5%) and after the intervention, 76 (8.6%) (P = .04) were recorded. Of the 130 incidents recorded before the intervention, 63 (48.5%) involved omission to indicate the urine volume, and of the 76 incidents recorded after the intervention, only 1 (1.3%) (P < .001) involved this omission. Forty of 302 patients (13.2%) surveyed reported problems and more than half (175; 57.9%) had to collect various urine samples sequentially. The RCV determined was 54.5% for a percentage of variation in volume of 24-hour urine (PVVI) of 19.0 +/- 16.5%. Therefore, micturition associated with a PVVI >+/-54.5% suggests that 24-hour urine collection by the patient was incomplete. The results obtained when applying the RCV after the intervention showed that 6.3% of the 24-hour urine samples should be rejected. -The percentage of preanalytic incidents was reduced by providing health care personnel with information and training. The percentage of variation in volume of 24-hour urine can be used to evaluate the variation in patients' micturition. Reference change value was shown to be useful when determining whether 24-hour urine was properly collected.

  11. Acceptability of participatory social network analysis for problem-solving in Australian Aboriginal health service partnerships

    PubMed Central

    2012-01-01

    Background While participatory social network analysis can help health service partnerships to solve problems, little is known about its acceptability in cross-cultural settings. We conducted two case studies of chronic illness service partnerships in 2007 and 2008 to determine whether participatory research incorporating social network analysis is acceptable for problem-solving in Australian Aboriginal health service delivery. Methods Local research groups comprising 13–19 partnership staff, policy officers and community members were established at each of two sites to guide the research and to reflect and act on the findings. Network and work practice surveys were conducted with 42 staff, and the results were fed back to the research groups. At the end of the project, 19 informants at the two sites were interviewed, and the researchers conducted critical reflection. The effectiveness and acceptability of the participatory social network method were determined quantitatively and qualitatively. Results Participants in both local research groups considered that the network survey had accurately described the links between workers related to the exchange of clinical and cultural information, team care relationships, involvement in service management and planning and involvement in policy development. This revealed the function of the teams and the roles of workers in each partnership. Aboriginal workers had a high number of direct links in the exchange of cultural information, illustrating their role as the cultural resource, whereas they had fewer direct links with other network members on clinical information exchange and team care. The problem of their current and future roles was discussed inside and outside the local research groups. According to the interview informants the participatory network analysis had opened the way for problem-solving by “putting issues on the table”. While there were confronting and ethically challenging aspects, these informants considered that with flexibility of data collection to account for the preferences of Aboriginal members, then the method was appropriate in cross-cultural contexts for the difficult discussions that are needed to improve partnerships. Conclusion Critical reflection showed that the preconditions for difficult discussions are, first, that partners have the capacity to engage in such discussions, second, that partners assess whether the effort required for these discussions is balanced by the benefits they gain from the partnership, and, third, that “boundary spanning” staff can facilitate commitment to partnership goals. PMID:22682504

  12. Interactive Engagement in the Large Lecture Environment

    NASA Astrophysics Data System (ADS)

    Dubson, Michael

    Watching a great physics lecture is like watching a great piano performance. It is can be inspiring, and it can give you insights, but it doesn't teach you to play piano. Students don't learn physics by watching expert professors perform at the board; they can only learn by practicing it themselves. Learning physics involves high-level thinking like formulating problem-solving strategies or explaining concepts to other humans. Learning is always messy, involving struggle, trial-and-error, and paradigm shifts. That learning struggle cannot be overcome with a more eloquent lecture; it can only be surmounted with prolonged, determined, active engagement by the student. I will demonstrate some techniques of active engagement, including clicker questions and in-class activities, which are designed to activate the student's higher-level thinking, get them actively involved in their learning, and start them on the path of productive struggle. These techniques are scalable; they work in classrooms with 30 or 300 students. This talk about audience participation will involve audience participation, so please put down your phone and be ready for a challenge.

  13. Spin determination at the Large Hadron Collider

    NASA Astrophysics Data System (ADS)

    Yavin, Itay

    The quantum field theory describing the Electroweak sector demands some new physics at the TeV scale in order to unitarize the scattering of longitudinal W bosons. If this new physics takes the form of a scalar Higgs boson then it is hard to understand the huge hierarchy of scales between the Electroweak scale ˜ TeV and the Planck scale ˜ 1019 GeV. This is known as the Naturalness problem. Normally, in order to solve this problem, new particles, in addition to the Higgs boson, are required to be present in the spectrum below a few TeV. If such particles are indeed discovered at the Large Hadron Collider it will become important to determine their spin. Several classes of models for physics beyond the Electroweak scale exist. Determining the spin of any such newly discovered particle could prove to be the only means of distinguishing between these different models. In the first part of this thesis; we present a thorough discussion regarding such a measurement. We survey the different potentially useful channels for spin determination and a detailed analysis of the most promising channel is performed. The Littlest Higgs model offers a way to solve the Hierarchy problem by introduring heavy partners to Standard Model particles with the same spin and quantum numbers. However, this model is only good up to ˜ 10 TeV. In the second part of this thesis we present an extension of this model into a strongly coupled theory above ˜ 10 TeV. We use the celebrated AdS/CFT correspondence to calculate properties of the low-energy physics in terms of high-energy parameters. We comment on some of the tensions inherent to such a construction involving a large-N CFT (or equivalently, an AdS space).

  14. Uncertainties in obtaining high reliability from stress-strength models

    NASA Technical Reports Server (NTRS)

    Neal, Donald M.; Matthews, William T.; Vangel, Mark G.

    1992-01-01

    There has been a recent interest in determining high statistical reliability in risk assessment of aircraft components. The potential consequences are identified of incorrectly assuming a particular statistical distribution for stress or strength data used in obtaining the high reliability values. The computation of the reliability is defined as the probability of the strength being greater than the stress over the range of stress values. This method is often referred to as the stress-strength model. A sensitivity analysis was performed involving a comparison of reliability results in order to evaluate the effects of assuming specific statistical distributions. Both known population distributions, and those that differed slightly from the known, were considered. Results showed substantial differences in reliability estimates even for almost nondetectable differences in the assumed distributions. These differences represent a potential problem in using the stress-strength model for high reliability computations, since in practice it is impossible to ever know the exact (population) distribution. An alternative reliability computation procedure is examined involving determination of a lower bound on the reliability values using extreme value distributions. This procedure reduces the possibility of obtaining nonconservative reliability estimates. Results indicated the method can provide conservative bounds when computing high reliability. An alternative reliability computation procedure is examined involving determination of a lower bound on the reliability values using extreme value distributions. This procedure reduces the possibility of obtaining nonconservative reliability estimates. Results indicated the method can provide conservative bounds when computing high reliability.

  15. Problem solving using soft systems methodology.

    PubMed

    Land, L

    This article outlines a method of problem solving which considers holistic solutions to complex problems. Soft systems methodology allows people involved in the problem situation to have control over the decision-making process.

  16. Students' Difficulties with Integration in Electricity

    ERIC Educational Resources Information Center

    Nguyen, Dong-Hai; Rebello, N. Sanjay

    2011-01-01

    This study investigates the common difficulties that students in introductory physics experience when solving problems involving integration in the context of electricity. We conducted teaching-learning interviews with 15 students in a second-semester calculus-based introductory physics course on several problems involving integration. We found…

  17. Developmental and Behavioral Needs and Service Use for Young Children in Child Welfare

    PubMed Central

    Stahmer, Aubyn C.; Leslie, Laurel K.; Hurlburt, Michael; Barth, Richard P.; Webb, Mary Bruce; Landsverk, John; Zhang, Jinjin

    2006-01-01

    Objective To determine the level of developmental and behavioral need in young children entering child welfare (CW), estimate early intervention services use, and examine variation in need and service use based on age and level of involvement with CW by using a national probability sample in the United States. Methods As part of the National Survey of Child and Adolescent Well-Being, data were collected on 2813 children <6 years old for whom possible abuse or neglect was investigated by CW agencies. Analyses used descriptive statistics to determine developmental and behavioral needs across 5 domains (cognition, behavior, communication, social, and adaptive functioning) and service use. Logistic regression was used to examine the relationship between independent variables (age, gender, race-ethnicity, maltreatment history, level of CW involvement, and developmental or behavior problems) and service use. Results Results indicate that age and level of CW involvement predict service use when controlling for need. Both toddlers (41.8%) and preschoolers (68.1%) in CW have high developmental and behavioral needs; however, few children are receiving services for these issues (22.7% overall). Children that remain with their biological parents have similar needs to those in out-of-home care but are less likely to use services. Children <3 years of age are least likely to use services. Conclusions Children referred to CW have high developmental and behavioral need regardless of the level of CW involvement. Both age and level of involvement influence service use when controlling for need. Mechanisms need to be developed to address disparities in access to intervention. PMID:16199698

  18. Mediation of the relationship between callous-unemotional traits and proactive aggression by amygdala response to fear among children with conduct problems.

    PubMed

    Lozier, Leah M; Cardinale, Elise M; VanMeter, John W; Marsh, Abigail A

    2014-06-01

    Among youths with conduct problems, callous-unemotional (CU) traits are known to be an important determinant of symptom severity, prognosis, and treatment responsiveness. But positive correlations between conduct problems and CU traits result in suppressor effects that may mask important neurobiological distinctions among subgroups of children with conduct problems. To assess the unique neurobiological covariates of CU traits and externalizing behaviors in youths with conduct problems and determine whether neural dysfunction linked to CU traits mediates the link between callousness and proactive aggression. This cross-sectional case-control study involved behavioral testing and neuroimaging that were conducted at a university research institution. Neuroimaging was conducted using a 3-T Siemens magnetic resonance imaging scanner. It included 46 community-recruited male and female juveniles aged 10 to 17 years, including 16 healthy control participants and 30 youths with conduct problems with both low and high levels of CU traits. Blood oxygenation level-dependent signal as measured via functional magnetic resonance imaging during an implicit face-emotion processing task and analyzed using whole-brain and region of interest-based analysis of variance and multiple-regression analyses. Analysis of variance revealed no group differences in the amygdala. By contrast, consistent with the existence of suppressor effects, multiple-regression analysis found amygdala responses to fearful expressions to be negatively associated with CU traits (x = 26, y = 0, z = -12; k = 1) and positively associated with externalizing behavior (x = 24, y = 0, z = -14; k = 8) when both variables were modeled simultaneously. Reduced amygdala responses mediated the relationship between CU traits and proactive aggression. The results linked proactive aggression in youths with CU traits to hypoactive amygdala responses to emotional distress cues, consistent with theories that externalizing behaviors, particularly proactive aggression, in youths with these traits stem from deficient empathic responses to distress. Amygdala hypoactivity may represent an intermediate phenotype, offering new insights into effective treatment strategies for conduct problems.

  19. Determinants and patterns of service utilization and recourse to professionals for mental health reasons

    PubMed Central

    2014-01-01

    Background This study has a dual purpose: 1) identify determinants of healthcare service utilization for mental health reasons (MHR) in a Canadian (Montreal) catchment area; 2) determine the patterns of recourse to healthcare professionals in terms of frequency of visits and type of professionals consulted, and as it relates to the most prevalent mental disorders (MD) and psychological distress. Methods Data was collected from a random sample of 1,823 individuals interviewed after a two-year follow-up period. A regression analysis was performed to identify variables associated with service utilization and complementary analyses were carried out to better understand participants’ patterns of healthcare service utilization in relation to the most prevalent MD. Results Among 243 individuals diagnosed with a MD in the 12 months preceding an interview, 113 (46.5%) reported having used healthcare services for MHR. Determinants of service utilization were emotional and legal problems, number of MD, higher personal income, lower quality of life, inability of individuals to influence events occurring in their neighborhood, female gender and, marginally, lack of alcohol dependence in the past 12 months. Emotional problems were the most significant determinant of healthcare service utilization. Frequent visits with healthcare professionals were more likely associated with major depression and number of MD with or without dependence to alcohol or drugs. People suffering from major depression, psychological distress and social phobia were more likely to consult different professionals, while individuals with panic disorders relied on their family physician only. Concerning social phobia, panic disorders and psychological distress, more frequent visits with professionals did not translate into involvement of a higher number of professionals or vice-versa. Conclusions This study demonstrates the impact of emotional problems, neighborhood characteristics and legal problems in healthcare service utilization for MHR. Interventions based on inter-professional collaboration could be prioritized to increase the ability of healthcare services to take care especially of individuals suffering from social phobia, panic disorders and psychological distress. Others actions that could be prioritized are training of family physicians in the treatment of MD, use of psychiatric consultants, internet outreach, and reimbursement of psychological consultations for individuals with low income. PMID:24712834

  20. Determination of points of entry for potential contaminants into limestone aquifers using thermal infrared imagery

    NASA Technical Reports Server (NTRS)

    Doyle, F. L.

    1974-01-01

    Lineations were identified involving the application of ERTS imagery to geologic and hydrologic problems. Interpretation of the southwest Madison County area is discussed. The tracing of the Beech Grove lineament to the northern boundary of Madison County, Alabama raises the question of its relationship to the trend of lineations in southwestern Madison County. The use of thermography as an indication of soil moisture is reviewed. The effect of soil moisture on surface temperature and the relationship between soil moisture and ground water are examined.

  1. Incorporating Duration Information in Activity Recognition

    NASA Astrophysics Data System (ADS)

    Chaurasia, Priyanka; Scotney, Bryan; McClean, Sally; Zhang, Shuai; Nugent, Chris

    Activity recognition has become a key issue in smart home environments. The problem involves learning high level activities from low level sensor data. Activity recognition can depend on several variables; one such variable is duration of engagement with sensorised items or duration of intervals between sensor activations that can provide useful information about personal behaviour. In this paper a probabilistic learning algorithm is proposed that incorporates episode, time and duration information to determine inhabitant identity and the activity being undertaken from low level sensor data. Our results verify that incorporating duration information consistently improves the accuracy.

  2. LTA structures and materials technology

    NASA Technical Reports Server (NTRS)

    Mayer, N. J.

    1975-01-01

    The state-of-the-art concerning structures and materials technology is reviewed. It is shown that many present materials developments resulting from balloon and aircraft research programs can be applied to new concepts in LTA vehicles. Both buoyant and semi-buoyant vehicles utilize similar approaches to solving structural problems and could involve pressurized non-rigid and unpressurized rigid structures. System designs common to both and vital to structural integrity include much of the past technology as well. Further research is needed in determination of structural loads, especially in future design concepts.

  3. [Normative dimensions of nursing practice--the ethical relevance of the body].

    PubMed

    Remmers, H

    1997-10-01

    A combination of preliminary considerations concerning a theory of action and a philosophy of science illustrates the determining influence of the scientific preconception of the subject matter, and of the approach which is presupposed by this preconception, on the normative orientation of nursing practice. The specific physical nearness involved in nursing practice ("body to body") holds problems with regard to an appropriate theoretical frame of reference and corresponding practical convictions. This background provides the context for a concluding critical examination of several representative nursing theories with regard to their implicit, normative premises.

  4. Self-Shadowing of a Spacecraft in the Computation of Surface Forces. An Example in Planetary Geodesy

    NASA Astrophysics Data System (ADS)

    Balmino, G.; Marty, J. C.

    2018-03-01

    We describe in details the algorithms used in modelling the self-shadowing between spacecraft components, which appears when computing the surface forces as precisely as possible and especially when moving parts are involved. This becomes necessary in planetary geodesy inverse problems using more and more precise orbital information to derive fundamental parameters of geophysical interest. Examples are given with two Mars orbiters, which show significant improvement on drag and solar radiation pressure model multiplying factors, a prerequisite for improving in turn the determination of other global models.

  5. A method for nonlinear exponential regression analysis

    NASA Technical Reports Server (NTRS)

    Junkin, B. G.

    1971-01-01

    A computer-oriented technique is presented for performing a nonlinear exponential regression analysis on decay-type experimental data. The technique involves the least squares procedure wherein the nonlinear problem is linearized by expansion in a Taylor series. A linear curve fitting procedure for determining the initial nominal estimates for the unknown exponential model parameters is included as an integral part of the technique. A correction matrix was derived and then applied to the nominal estimate to produce an improved set of model parameters. The solution cycle is repeated until some predetermined criterion is satisfied.

  6. On the computation of steady Hopper flows. II: von Mises materials in various geometries

    NASA Astrophysics Data System (ADS)

    Gremaud, Pierre A.; Matthews, John V.; O'Malley, Meghan

    2004-11-01

    Similarity solutions are constructed for the flow of granular materials through hoppers. Unlike previous work, the present approach applies to nonaxisymmetric containers. The model involves ten unknowns (stresses, velocity, and plasticity function) determined by nine nonlinear first order partial differential equations together with a quadratic algebraic constraint (yield condition). A pseudospectral discretization is applied; the resulting problem is solved with a trust region method. The important role of the hopper geometry on the flow is illustrated by several numerical experiments of industrial relevance.

  7. Optimal steering for kinematic vehicles with applications to spatially distributed agents

    NASA Astrophysics Data System (ADS)

    Brown, Scott; Praeger, Cheryl E.; Giudici, Michael

    While there is no universal method to address control problems involving networks of autonomous vehicles, there exist a few promising schemes that apply to different specific classes of problems, which have attracted the attention of many researchers from different fields. In particular, one way to extend techniques that address problems involving a single autonomous vehicle to those involving teams of autonomous vehicles is to use the concept of Voronoi diagram. The Voronoi diagram provides a spatial partition of the environment the team of vehicles operate in, where each element of this partition is associated with a unique vehicle from the team. The partition induces a graph abstraction of the operating space that is in an one-to-one correspondence with the network abstraction of the team of autonomous vehicles; a fact that can provide both conceptual and analytical advantages during mission planning and execution. In this dissertation, we propose the use of a new class of Voronoi-like partitioning schemes with respect to state-dependent proximity (pseudo-) metrics rather than the Euclidean distance or other generalized distance functions, which are typically used in the literature. An important nuance here is that, in contrast to the Euclidean distance, state-dependent metrics can succinctly capture system theoretic features of each vehicle from the team (e.g., vehicle kinematics), as well as the environment-vehicle interactions, which are induced, for example, by local winds/currents. We subsequently illustrate how the proposed concept of state-dependent Voronoi-like partition can induce local control schemes for problems involving networks of spatially distributed autonomous vehicles by examining a sequential pursuit problem of a maneuvering target by a group of pursuers distributed in the plane. The construction of generalized Voronoi diagrams with respect to state-dependent metrics poses some significant challenges. First, the generalized distance metric may be a function of the direction of motion of the vehicle (anisotropic pseudo-distance function) and/or may not be expressible in closed form. Second, such problems fall under the general class of partitioning problems for which the vehicles' dynamics must be taken into account. The topology of the vehicle's configuration space may be non-Euclidean, for example, it may be a manifold embedded in a Euclidean space. In other words, these problems may not be reducible to generalized Voronoi diagram problems for which efficient construction schemes, analytical and/or computational, exist in the literature. This research effort pursues three main objectives. First, we present the complete solution of different steering problems involving a single vehicle in the presence of motion constraints imposed by the maneuverability envelope of the vehicle and/or the presence of a drift field induced by winds/currents in its vicinity. The analysis of each steering problem involving a single vehicle provides us with a state-dependent generalized metric, such as the minimum time-to-go/come. We subsequently use these state-dependent generalized distance functions as the proximity metrics in the formulation of generalized Voronoi-like partitioning problems. The characterization of the solutions of these state-dependent Voronoi-like partitioning problems using either analytical or computational techniques constitutes the second main objective of this dissertation. The third objective of this research effort is to illustrate the use of the proposed concept of state-dependent Voronoi-like partition as a means for passing from control techniques that apply to problems involving a single vehicle to problems involving networks of spatially distributed autonomous vehicles. To this aim, we formulate the problem of sequential/relay pursuit of a maneuvering target by a group of spatially distributed pursuers and subsequently propose a distributed group pursuit strategy that directly derives from the solution of a state-dependent Voronoi-like partitioning problem. (Abstract shortened by UMI.)

  8. Feeding Problems in Healthy Young Children: Prevalence, Related Factors and Feeding Practices

    PubMed Central

    Benjasuwantep, Banchaun; Chaithirayanon, Suthida; Eiamudomkan, Monchutha

    2013-01-01

    The aim of this study was to determine the prevalence, characteristics, and factors related to feeding problems among normal children, and the differences in feeding practices between those with and without feeding problems. Caregivers of 402 healthy children aged between one and four years of age were interviewed by pediatricians involved in the research. Data included the child’s medical history, food intake within a day, and feeding behaviors and practices. Parental socio-economic and demographic information, as well as information on parental education and occupation, and their concerns about feeding their children, was collected. Physical examination and anthropometric measurements were taken. The percentage of children identified as having feeding problems was 26.9%. The first child of a family had an increased risk of having feeding problems [P=0.032, odds ratio 1.68, 95% confidence interval (95%CI) 1.04-2.71]. Children with feeding problems were fed less frequently, were less likely to be fed at their own table or at the family table, and had mealtimes longer than 30 min when compared with children without feeding problems (P=0.015, 0.004 and 0.025, respectively). The results highlight that feeding problems in normally developing children are common. During consultations about feeding issues, pediatricians should focus on families with a first child. Topics such as frequency of meals per day, duration of mealtimes, and appropriate places for feeding should be discussed. PMID:23904965

  9. Predicting gambling problems from gambling outcome expectancies in college student-athletes.

    PubMed

    St-Pierre, Renée A; Temcheff, Caroline E; Gupta, Rina; Derevensky, Jeffrey; Paskus, Thomas S

    2014-03-01

    While previous research has suggested the potential importance of gambling outcome expectancies in determining gambling behaviour among adolescents, the predictive ability of gambling outcome expectancies has not yet been clearly delineated for college-aged youth. The current study aims to explore the relationships between gender and outcome expectancies in the prediction of gambling severity among college student-athletes. Data from the National Collegiate Athletic Association (NCAA) study assessing gambling behaviours and problems among U.S. college student-athletes were utilized. Complete data was available for 7,517 student-athletes. As expected, male college student-athletes reported more gambling participation as well as greater gambling problems than their female counterparts. Findings showed positive relationships between the outcome expectancies of financial gain, and negative emotional impacts and gambling problems. That is, those who endorsed more items on the outcome expectancy scales for financial gain and negative emotional impacts also tended to endorse more gambling-related problems. Findings also showed a negative relationship between outcome expectancies of fun and enjoyment, and gambling problems over and above the variance accounted for by gender. Those with gambling problems were less likely to have the expectation that gambling would be fun than those without gambling problems. Despite NCAA efforts to curb gambling activity, the results suggest that college student-athletes are at risk for over-involvement in gambling. Therefore, it is important to explore gambling outcome expectancies within this group since the motivations and reasons for gambling might be able to inform treatment initiatives.

  10. Anxiety, Depression and Emotion Regulation Among Regular Online Poker Players.

    PubMed

    Barrault, Servane; Bonnaire, Céline; Herrmann, Florian

    2017-12-01

    Poker is a type of gambling that has specific features, including the need to regulate one's emotion to be successful. The aim of the present study is to assess emotion regulation, anxiety and depression in a sample of regular poker players, and to compare the results of problem and non-problem gamblers. 416 regular online poker players completed online questionnaires including sociodemographic data, measures of problem gambling (CPGI), anxiety and depression (HAD scale), and emotion regulation (ERQ). The CPGI was used to divide participants into four groups according to the intensity of their gambling practice (non-problem, low risk, moderate risk and problem gamblers). Anxiety and depression were significantly higher among severe-problem gamblers than among the other groups. Both significantly predicted problem gambling. On the other hand, there was no difference between groups in emotion regulation (cognitive reappraisal and expressive suppression), which was linked neither to problem gambling nor to anxiety and depression (except for cognitive reappraisal, which was significantly correlated to anxiety). Our results underline the links between anxiety, depression and problem gambling among poker players. If emotion regulation is involved in problem gambling among poker players, as strongly suggested by data from the literature, the emotion regulation strategies we assessed (cognitive reappraisal and expressive suppression) may not be those involved. Further studies are thus needed to investigate the involvement of other emotion regulation strategies.

  11. Predicting the Problem Behavior in Adolescents

    ERIC Educational Resources Information Center

    Karaman, Neslihan G.

    2013-01-01

    Problem statement: Problem behavior theory describes both protective factors and risk factors to explain adolescent problem behaviors, such as delinquency, alcohol use, and reckless driving. The theory holds that problem behaviors involving risky behavior are used by adolescents as a means to gain peer acceptance and respect. Problem behaviors…

  12. Virtual Bridge Design

    ERIC Educational Resources Information Center

    Bisogno, Janet; JeanPierre, Bobby

    2008-01-01

    The West Point Bridge Design (WPBD) building project engages students in project-based learning by giving them a real-life problem to solve. By using technology, students are able to become involved in solving problems that they normally would not encounter. Involvement with interactive websites, such as WPBD, assists students in using…

  13. Suicidal Ideation among Adolescent School Children, Involvement in Bully-Victim Problems, and Perceived Social Support.

    ERIC Educational Resources Information Center

    Rigby, Ken; Slee, Phillip

    1999-01-01

    Results of self-reports and peer nomination procedures to identify bullies and victims indicated that involvement in bully-victim problems at school, especially for students with relatively little social support, was significantly related to degree of suicidal ideation. (Author/JDM)

  14. A simple suboptimal least-squares algorithm for attitude determination with multiple sensors

    NASA Technical Reports Server (NTRS)

    Brozenec, Thomas F.; Bender, Douglas J.

    1994-01-01

    Three-axis attitude determination is equivalent to finding a coordinate transformation matrix which transforms a set of reference vectors fixed in inertial space to a set of measurement vectors fixed in the spacecraft. The attitude determination problem can be expressed as a constrained optimization problem. The constraint is that a coordinate transformation matrix must be proper, real, and orthogonal. A transformation matrix can be thought of as optimal in the least-squares sense if it maps the measurement vectors to the reference vectors with minimal 2-norm errors and meets the above constraint. This constrained optimization problem is known as Wahba's problem. Several algorithms which solve Wahba's problem exactly have been developed and used. These algorithms, while steadily improving, are all rather complicated. Furthermore, they involve such numerically unstable or sensitive operations as matrix determinant, matrix adjoint, and Newton-Raphson iterations. This paper describes an algorithm which minimizes Wahba's loss function, but without the constraint. When the constraint is ignored, the problem can be solved by a straightforward, numerically stable least-squares algorithm such as QR decomposition. Even though the algorithm does not explicitly take the constraint into account, it still yields a nearly orthogonal matrix for most practical cases; orthogonality only becomes corrupted when the sensor measurements are very noisy, on the same order of magnitude as the attitude rotations. The algorithm can be simplified if the attitude rotations are small enough so that the approximation sin(theta) approximately equals theta holds. We then compare the computational requirements for several well-known algorithms. For the general large-angle case, the QR least-squares algorithm is competitive with all other know algorithms and faster than most. If attitude rotations are small, the least-squares algorithm can be modified to run faster, and this modified algorithm is faster than all but a similarly specialized version of the QUEST algorithm. We also introduce a novel measurement averaging technique which reduces the n-measurement case to the two measurement case for our particular application, a star tracker and earth sensor mounted on an earth-pointed geosynchronous communications satellite. Using this technique, many n-measurement problems reduce to less than or equal to 3 measurements; this reduces the amount of required calculation without significant degradation in accuracy. Finally, we present the results of some tests which compare the least-squares algorithm with the QUEST and FOAM algorithms in the two-measurement case. For our example case, all three algorithms performed with similar accuracy.

  15. Implicit time-integration method for simultaneous solution of a coupled non-linear system

    NASA Astrophysics Data System (ADS)

    Watson, Justin Kyle

    Historically large physical problems have been divided into smaller problems based on the physics involved. This is no different in reactor safety analysis. The problem of analyzing a nuclear reactor for design basis accidents is performed by a handful of computer codes each solving a portion of the problem. The reactor thermal hydraulic response to an event is determined using a system code like TRAC RELAP Advanced Computational Engine (TRACE). The core power response to the same accident scenario is determined using a core physics code like Purdue Advanced Core Simulator (PARCS). Containment response to the reactor depressurization in a Loss Of Coolant Accident (LOCA) type event is calculated by a separate code. Sub-channel analysis is performed with yet another computer code. This is just a sample of the computer codes used to solve the overall problems of nuclear reactor design basis accidents. Traditionally each of these codes operates independently from each other using only the global results from one calculation as boundary conditions to another. Industry's drive to uprate power for reactors has motivated analysts to move from a conservative approach to design basis accident towards a best estimate method. To achieve a best estimate calculation efforts have been aimed at coupling the individual physics models to improve the accuracy of the analysis and reduce margins. The current coupling techniques are sequential in nature. During a calculation time-step data is passed between the two codes. The individual codes solve their portion of the calculation and converge to a solution before the calculation is allowed to proceed to the next time-step. This thesis presents a fully implicit method of simultaneous solving the neutron balance equations, heat conduction equations and the constitutive fluid dynamics equations. It discusses the problems involved in coupling different physics phenomena within multi-physics codes and presents a solution to these problems. The thesis also outlines the basic concepts behind the nodal balance equations, heat transfer equations and the thermal hydraulic equations, which will be coupled to form a fully implicit nonlinear system of equations. The coupling of separate physics models to solve a larger problem and improve accuracy and efficiency of a calculation is not a new idea, however implementing them in an implicit manner and solving the system simultaneously is. Also the application to reactor safety codes is new and has not be done with thermal hydraulics and neutronics codes on realistic applications in the past. The coupling technique described in this thesis is applicable to other similar coupled thermal hydraulic and core physics reactor safety codes. This technique is demonstrated using coupled input decks to show that the system is solved correctly and then verified by using two derivative test problems based on international benchmark problems the OECD/NRC Three mile Island (TMI) Main Steam Line Break (MSLB) problem (representative of pressurized water reactor analysis) and the OECD/NRC Peach Bottom (PB) Turbine Trip (TT) benchmark (representative of boiling water reactor analysis).

  16. Investigating the effect of mental set on insight problem solving.

    PubMed

    Ollinger, Michael; Jones, Gary; Knoblich, Günther

    2008-01-01

    Mental set is the tendency to solve certain problems in a fixed way based on previous solutions to similar problems. The moment of insight occurs when a problem cannot be solved using solution methods suggested by prior experience and the problem solver suddenly realizes that the solution requires different solution methods. Mental set and insight have often been linked together and yet no attempt thus far has systematically examined the interplay between the two. Three experiments are presented that examine the extent to which sets of noninsight and insight problems affect the subsequent solutions of insight test problems. The results indicate a subtle interplay between mental set and insight: when the set involves noninsight problems, no mental set effects are shown for the insight test problems, yet when the set involves insight problems, both facilitation and inhibition can be seen depending on the type of insight problem presented in the set. A two process model is detailed to explain these findings that combines the representational change mechanism with that of proceduralization.

  17. Processes involved in solving mathematical problems

    NASA Astrophysics Data System (ADS)

    Shahrill, Masitah; Putri, Ratu Ilma Indra; Zulkardi, Prahmana, Rully Charitas Indra

    2018-04-01

    This study examines one of the instructional practices features utilized within the Year 8 mathematics lessons in Brunei Darussalam. The codes from the TIMSS 1999 Video Study were applied and strictly followed, and from the 183 mathematics problems recorded, there were 95 problems with a solution presented during the public segments of the video-recorded lesson sequences of the four sampled teachers. The analyses involved firstly, identifying the processes related to mathematical problem statements, and secondly, examining the different processes used in solving the mathematical problems for each problem publicly completed during the lessons. The findings revealed that for three of the teachers, their problem statements coded as `using procedures' ranged from 64% to 83%, while the remaining teacher had 40% of his problem statements coded as `making connections.' The processes used when solving the problems were mainly `using procedures', and none of the problems were coded as `giving results only'. Furthermore, all four teachers made use of making the relevant connections in solving the problems given to their respective students.

  18. Difference equation state approximations for nonlinear hereditary control problems

    NASA Technical Reports Server (NTRS)

    Rosen, I. G.

    1984-01-01

    Discrete approximation schemes for the solution of nonlinear hereditary control problems are constructed. The methods involve approximation by a sequence of optimal control problems in which the original infinite dimensional state equation has been approximated by a finite dimensional discrete difference equation. Convergence of the state approximations is argued using linear semigroup theory and is then used to demonstrate that solutions to the approximating optimal control problems in some sense approximate solutions to the original control problem. Two schemes, one based upon piecewise constant approximation, and the other involving spline functions are discussed. Numerical results are presented, analyzed and used to compare the schemes to other available approximation methods for the solution of hereditary control problems. Previously announced in STAR as N83-33589

  19. Individualized Math Problems in Fractions. Oregon Vo-Tech Mathematics Problem Sets.

    ERIC Educational Resources Information Center

    Cosler, Norma, Ed.

    This is one of eighteen sets of individualized mathematics problems developed by the Oregon Vo-Tech Math Project. Each of these problem packages is organized around a mathematical topic and contains problems related to diverse vocations. Solutions are provided for all problems. This package contains problems involving computation with common…

  20. Individualized Math Problems in Measurement and Conversion. Oregon Vo-Tech Mathematics Problem Sets.

    ERIC Educational Resources Information Center

    Cosler, Norma, Ed.

    This is one of eighteen sets of individualized mathematics problems developed by the Oregon Vo-Tech Math Project. Each of these problem packages is organized around a mathematical topic and contains problems related to diverse vocations. Solutions are provided for all problems. This volume includes problems involving measurement, computation of…

  1. Individualized Math Problems in Integers. Oregon Vo-Tech Mathematics Problem Sets.

    ERIC Educational Resources Information Center

    Cosler, Norma, Ed.

    This is one of eighteen sets of individualized mathematics problems developed by the Oregon Vo-Tech Math Project. Each of these problem packages is organized around a mathematical topic and contains problems related to diverse vocations. Solutions are provided for all problems. This volume presents problems involving operations with positive and…

  2. Enhancing chemistry problem-solving achievement using problem categorization

    NASA Astrophysics Data System (ADS)

    Bunce, Diane M.; Gabel, Dorothy L.; Samuel, John V.

    The enhancement of chemistry students' skill in problem solving through problem categorization is the focus of this study. Twenty-four students in a freshman chemistry course for health professionals are taught how to solve problems using the explicit method of problem solving (EMPS) (Bunce & Heikkinen, 1986). The EMPS is an organized approach to problem analysis which includes encoding the information given in a problem (Given, Asked For), relating this to what is already in long-term memory (Recall), and planning a solution (Overall Plan) before a mathematical solution is attempted. In addition to the EMPS training, treatment students receive three 40-minute sessions following achievement tests in which they are taught how to categorize problems. Control students use this time to review the EMPS solutions of test questions. Although problem categorization is involved in one section of the EMPS (Recall), treatment students who received specific training in problem categorization demonstrate significantly higher achievement on combination problems (those problems requiring the use of more than one chemical topic for their solution) at (p = 0.01) than their counterparts. Significantly higher achievement for treatment students is also measured on an unannounced test (p = 0.02). Analysis of interview transcripts of both treatment and control students illustrates a Rolodex approach to problem solving employed by all students in this study. The Rolodex approach involves organizing equations used to solve problems on mental index cards and flipping through them, matching units given when a new problem is to be solved. A second phenomenon observed during student interviews is the absence of a link in the conceptual understanding of the chemical concepts involved in a problem and the problem-solving skills employed to correctly solve problems. This study shows that explicit training in categorization skills and the EMPS can lead to higher achievement in complex problem-solving situations (combination problems and unannounced test). However, such achievement may be limited by the lack of linkages between students' conceptual understanding and improved problem-solving skill.

  3. The MCNP6 Analytic Criticality Benchmark Suite

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

    Brown, Forrest B.

    2016-06-16

    Analytical benchmarks provide an invaluable tool for verifying computer codes used to simulate neutron transport. Several collections of analytical benchmark problems [1-4] are used routinely in the verification of production Monte Carlo codes such as MCNP® [5,6]. Verification of a computer code is a necessary prerequisite to the more complex validation process. The verification process confirms that a code performs its intended functions correctly. The validation process involves determining the absolute accuracy of code results vs. nature. In typical validations, results are computed for a set of benchmark experiments using a particular methodology (code, cross-section data with uncertainties, and modeling)more » and compared to the measured results from the set of benchmark experiments. The validation process determines bias, bias uncertainty, and possibly additional margins. Verification is generally performed by the code developers, while validation is generally performed by code users for a particular application space. The VERIFICATION_KEFF suite of criticality problems [1,2] was originally a set of 75 criticality problems found in the literature for which exact analytical solutions are available. Even though the spatial and energy detail is necessarily limited in analytical benchmarks, typically to a few regions or energy groups, the exact solutions obtained can be used to verify that the basic algorithms, mathematics, and methods used in complex production codes perform correctly. The present work has focused on revisiting this benchmark suite. A thorough review of the problems resulted in discarding some of them as not suitable for MCNP benchmarking. For the remaining problems, many of them were reformulated to permit execution in either multigroup mode or in the normal continuous-energy mode for MCNP. Execution of the benchmarks in continuous-energy mode provides a significant advance to MCNP verification methods.« less

  4. Rapid processing of data based on high-performance algorithms for solving inverse problems and 3D-simulation of the tsunami and earthquakes

    NASA Astrophysics Data System (ADS)

    Marinin, I. V.; Kabanikhin, S. I.; Krivorotko, O. I.; Karas, A.; Khidasheli, D. G.

    2012-04-01

    We consider new techniques and methods for earthquake and tsunami related problems, particularly - inverse problems for the determination of tsunami source parameters, numerical simulation of long wave propagation in soil and water and tsunami risk estimations. In addition, we will touch upon the issue of database management and destruction scenario visualization. New approaches and strategies, as well as mathematical tools and software are to be shown. The long joint investigations by researchers of the Institute of Mathematical Geophysics and Computational Mathematics SB RAS and specialists from WAPMERR and Informap have produced special theoretical approaches, numerical methods, and software tsunami and earthquake modeling (modeling of propagation and run-up of tsunami waves on coastal areas), visualization, risk estimation of tsunami, and earthquakes. Algorithms are developed for the operational definition of the origin and forms of the tsunami source. The system TSS numerically simulates the source of tsunami and/or earthquakes and includes the possibility to solve the direct and the inverse problem. It becomes possible to involve advanced mathematical results to improve models and to increase the resolution of inverse problems. Via TSS one can construct maps of risks, the online scenario of disasters, estimation of potential damage to buildings and roads. One of the main tools for the numerical modeling is the finite volume method (FVM), which allows us to achieve stability with respect to possible input errors, as well as to achieve optimum computing speed. Our approach to the inverse problem of tsunami and earthquake determination is based on recent theoretical results concerning the Dirichlet problem for the wave equation. This problem is intrinsically ill-posed. We use the optimization approach to solve this problem and SVD-analysis to estimate the degree of ill-posedness and to find the quasi-solution. The software system we developed is intended to create technology «no frost», realizing a steady stream of direct and inverse problems: solving the direct problem, the visualization and comparison with observed data, to solve the inverse problem (correction of the model parameters). The main objective of further work is the creation of a workstation operating emergency tool that could be used by an emergency duty person in real time.

  5. Motivational dynamics of eating regulation: a self-determination theory perspective

    PubMed Central

    2012-01-01

    Within Western society, many people have difficulties adequately regulating their eating behaviors and weight. Although the literature on eating regulation is vast, little attention has been given to motivational dynamics involved in eating regulation. Grounded in Self-Determination Theory (SDT), the present contribution aims to provide a motivational perspective on eating regulation. The role of satisfaction and thwarting of the basic psychological needs for autonomy, competence, and relatedness is introduced as a mechanism to (a) explain the etiology of body image concerns and disordered eating and (b) understand the optimal regulation of ongoing eating behavior for healthy weight maintenance. An overview of empirical studies on these two research lines is provided. In a final section, the potential relevance and value of SDT in relation to prevailing theoretical models in the domain of eating regulation is discussed. Although research on SDT in the domain of eating regulation is still in its early stages and more research is clearly needed, this review suggests that the SDT represents a promising framework to more thoroughly study and understand the motivational processes involved in eating regulation and associated problems. PMID:22385782

  6. Recurrence Methods for the Identification of Morphogenetic Patterns

    PubMed Central

    Facchini, Angelo; Mocenni, Chiara

    2013-01-01

    This paper addresses the problem of identifying the parameters involved in the formation of spatial patterns in nonlinear two dimensional systems. To this aim, we perform numerical experiments on a prototypical model generating morphogenetic Turing patterns, by changing both the spatial frequency and shape of the patterns. The features of the patterns and their relationship with the model parameters are characterized by means of the Generalized Recurrence Quantification measures. We show that the recurrence measures Determinism and Recurrence Entropy, as well as the distribution of the line lengths, allow for a full characterization of the patterns in terms of power law decay with respect to the parameters involved in the determination of their spatial frequency and shape. A comparison with the standard two dimensional Fourier transform is performed and the results show a better performance of the recurrence indicators in identifying a reliable connection with the spatial frequency of the patterns. Finally, in order to evaluate the robustness of the estimation of the power low decay, extensive simulations have been performed by adding different levels of noise to the patterns. PMID:24066062

  7. Problems on Divisibility of Binomial Coefficients

    ERIC Educational Resources Information Center

    Osler, Thomas J.; Smoak, James

    2004-01-01

    Twelve unusual problems involving divisibility of the binomial coefficients are represented in this article. The problems are listed in "The Problems" section. All twelve problems have short solutions which are listed in "The Solutions" section. These problems could be assigned to students in any course in which the binomial theorem and Pascal's…

  8. Energy-efficient container handling using hybrid model predictive control

    NASA Astrophysics Data System (ADS)

    Xin, Jianbin; Negenborn, Rudy R.; Lodewijks, Gabriel

    2015-11-01

    The performance of container terminals needs to be improved to adapt the growth of containers while maintaining sustainability. This paper provides a methodology for determining the trajectory of three key interacting machines for carrying out the so-called bay handling task, involving transporting containers between a vessel and the stacking area in an automated container terminal. The behaviours of the interacting machines are modelled as a collection of interconnected hybrid systems. Hybrid model predictive control (MPC) is proposed to achieve optimal performance, balancing the handling capacity and energy consumption. The underlying control problem is hereby formulated as a mixed-integer linear programming problem. Simulation studies illustrate that a higher penalty on energy consumption indeed leads to improved sustainability using less energy. Moreover, simulations illustrate how the proposed energy-efficient hybrid MPC controller performs under different types of uncertainties.

  9. Occupational health scenario of Indian informal sector

    PubMed Central

    NAG, Anjali; VYAS, Heer; NAG, Pranab

    2016-01-01

    Workers in the Indian informal sector are engaged with different occupations. These occupations involve varied work related hazards. These occupational hazards are a consequent risk to health. The study aimed to determine occupational health scenario in the Indian Informal sector. One thousand eleven hundred twenty two workers from five different occupations namely weaving (handloom and power loom), construction, transportation, tobacco processing and fish processing were assessed by interviewer administered health questionnaire. Workers suffered from musculo-skeletal complaints, respiratory health hazards, eye problems and skin related complaints. There was a high prevalence of self-reported occupational health problems in the selected sectors. The study finds that workers have occupational exposures to multiple hazards. The absence of protective guards aggrevate their health condition. The study attempts to draws an immediate attention on the existing health scenario of the Indian Informal sector. PMID:26903262

  10. Solutions for the conductivity of multi-coated spheres and spherically symmetric inclusion problems

    NASA Astrophysics Data System (ADS)

    Pham, Duc Chinh

    2018-02-01

    Variational results on the macroscopic conductivity (thermal, electrical, etc.) of the multi-coated sphere assemblage have been used to derive the explicit expression of the respective field (thermal, electrical, etc.) within the spheres in d dimensions (d=2,3). A differential substitution approach has been developed to construct various explicit expressions or determining equations for the effective spherically symmetric inclusion problems, which include those with radially variable conductivity, different radially variable transverse and normal conductivities, and those involving imperfect interfaces, in d dimensions. When the volume proportion of the outermost spherical shell increases toward 1, one obtains the respective exact results for the most important specific cases: the dilute solutions for the compound inhomogeneities suspended in a major matrix phase. Those dilute solution results are also needed for other effective medium approximation schemes.

  11. Initial value formulation of dynamical Chern-Simons gravity

    NASA Astrophysics Data System (ADS)

    Delsate, Térence; Hilditch, David; Witek, Helvi

    2015-01-01

    We derive an initial value formulation for dynamical Chern-Simons gravity, a modification of general relativity involving parity-violating higher derivative terms. We investigate the structure of the resulting system of partial differential equations thinking about linearization around arbitrary backgrounds. This type of consideration is necessary if we are to establish well-posedness of the Cauchy problem. Treating the field equations as an effective field theory we find that weak necessary conditions for hyperbolicity are satisfied. For the full field equations we find that there are states from which subsequent evolution is not determined. Generically the evolution system closes, but is not hyperbolic in any sense that requires a first order pseudodifferential reduction. In a cursory mode analysis we find that the equations of motion contain terms that may cause ill-posedness of the initial value problem.

  12. Occupational health scenario of Indian informal sector.

    PubMed

    Nag, Anjali; Vyas, Heer; Nag, Pranab

    2016-08-05

    Workers in the Indian informal sector are engaged with different occupations. These occupations involve varied work related hazards. These occupational hazards are a consequent risk to health. The study aimed to determine occupational health scenario in the Indian Informal sector. One thousand eleven hundred twenty two workers from five different occupations namely weaving (handloom and power loom), construction, transportation, tobacco processing and fish processing were assessed by interviewer administered health questionnaire. Workers suffered from musculo-skeletal complaints, respiratory health hazards, eye problems and skin related complaints. There was a high prevalence of self-reported occupational health problems in the selected sectors. The study finds that workers have occupational exposures to multiple hazards. The absence of protective guards aggrevate their health condition. The study attempts to draws an immediate attention on the existing health scenario of the Indian Informal sector.

  13. Advanced Methods for Determining Prediction Uncertainty in Model-Based Prognostics with Application to Planetary Rovers

    NASA Technical Reports Server (NTRS)

    Daigle, Matthew J.; Sankararaman, Shankar

    2013-01-01

    Prognostics is centered on predicting the time of and time until adverse events in components, subsystems, and systems. It typically involves both a state estimation phase, in which the current health state of a system is identified, and a prediction phase, in which the state is projected forward in time. Since prognostics is mainly a prediction problem, prognostic approaches cannot avoid uncertainty, which arises due to several sources. Prognostics algorithms must both characterize this uncertainty and incorporate it into the predictions so that informed decisions can be made about the system. In this paper, we describe three methods to solve these problems, including Monte Carlo-, unscented transform-, and first-order reliability-based methods. Using a planetary rover as a case study, we demonstrate and compare the different methods in simulation for battery end-of-discharge prediction.

  14. Fluid mechanics in crystal growth - The 1982 Freeman scholar lecture

    NASA Technical Reports Server (NTRS)

    Ostrach, S.

    1983-01-01

    An attempt is made to unify the current state of knowledge in crystal growth techniques and fluid mechanics. After identifying important fluid dynamic problems for such representative crystal growth processes as closed tube vapor transport, open reactor vapor deposition, and the Czochralski and floating zone melt growth techniques, research results obtained to date are presented. It is noted that the major effort to date has been directed to the description of the nature and extent of bulk transport under realistic conditions, where bulk flow determines the heat and solute transport which strongly influence the temperature and concentration fields in the vicinity of the growth interface. Proper treatment of near field, or interface, problems cannot be given until the far field, or global flow, involved in a given crystal growth technique has been adequately described.

  15. Optimal use of human and machine resources for Space Station assembly operations

    NASA Technical Reports Server (NTRS)

    Parrish, Joseph C.

    1988-01-01

    This paper investigates the issues involved in determining the best mix of human and machine resources for assembly of the Space Station. It presents the current Station assembly sequence, along with descriptions of the available assembly resources. A number of methodologies for optimizing the human/machine tradeoff problem have been developed, but the Space Station assembly offers some unique issues that have not yet been addressed. These include a strong constraint on available EVA time for early flights and a phased deployment of assembly resources over time. A methodology for incorporating the previously developed decision methods to the special case of the Space Station is presented. This methodology emphasizes an application of multiple qualitative and quantitative techniques, including simulation and decision analysis, for producing an objective, robust solution to the tradeoff problem.

  16. Exact finite element method analysis of viscoelastic tapered structures to transient loads

    NASA Technical Reports Server (NTRS)

    Spyrakos, Constantine Chris

    1987-01-01

    A general method is presented for determining the dynamic torsional/axial response of linear structures composed of either tapered bars or shafts to transient excitations. The method consists of formulating and solving the dynamic problem in the Laplace transform domain by the finite element method and obtaining the response by a numerical inversion of the transformed solution. The derivation of the torsional and axial stiffness matrices is based on the exact solution of the transformed governing equation of motion, and it consequently leads to the exact solution of the problem. The solution permits treatment of the most practical cases of linear tapered bars and shafts, and employs modeling of structures with only one element per member which reduces the number of degrees of freedom involved. The effects of external viscous or internal viscoelastic damping are also taken into account.

  17. Fathering and adolescents' psychological adjustment: the role of fathers' involvement, residence and biology status.

    PubMed

    Flouri, E

    2008-03-01

    Studies on fathering and child mental health are now increasingly looking for specificity in children's psychological adjustment, indicating whether the impact of fathering is diagnostically specific or non-specific. Data from 435 fathers of secondary school-aged children in Britain were used to explore the association between resident biological fathers', non-resident biological fathers' and stepfathers' involvement and children's total difficulties, prosocial behaviour, emotional symptoms, conduct problems, hyperactivity and peer problems (all measured with the Strengths and Difficulties Questionnaire) in adolescence. After controlling for child-, father- and family-related factors, fathers' involvement was negatively associated with children's total difficulties and hyperactivity, was positively associated with children's prosocial behaviour, and was unrelated with children's emotional symptoms, conduct problems and peer problems. There was no non-resident biological father effect. Compared with resident biological fathers, stepfathers reported more total difficulties, conduct problems and hyperactivity in their children even after adjusting for involvement. Whether this reflects stepfathers' low tolerance levels or biological fathers' complacency, as sociobiologists would argue, or whether this is due to pre-existing predispositions of children in families which separate and restructure, to the effects of these multiple family changes or to the high exposure of children in restructured families to parental risk factors, is, given the data available and the study design, unclear. However, this study showed that, compared with their peers in biological father families, adolescents in stepfather families are perceived to be at higher risk of behaviour problems, and that father involvement is related to specific aspects of child adjustment.

  18. A model for solving the prescribed burn planning problem.

    PubMed

    Rachmawati, Ramya; Ozlen, Melih; Reinke, Karin J; Hearne, John W

    2015-01-01

    The increasing frequency of destructive wildfires, with a consequent loss of life and property, has led to fire and land management agencies initiating extensive fuel management programs. This involves long-term planning of fuel reduction activities such as prescribed burning or mechanical clearing. In this paper, we propose a mixed integer programming (MIP) model that determines when and where fuel reduction activities should take place. The model takes into account multiple vegetation types in the landscape, their tolerance to frequency of fire events, and keeps track of the age of each vegetation class in each treatment unit. The objective is to minimise fuel load over the planning horizon. The complexity of scheduling fuel reduction activities has led to the introduction of sophisticated mathematical optimisation methods. While these approaches can provide optimum solutions, they can be computationally expensive, particularly for fuel management planning which extends across the landscape and spans long term planning horizons. This raises the question of how much better do exact modelling approaches compare to simpler heuristic approaches in their solutions. To answer this question, the proposed model is run using an exact MIP (using commercial MIP solver) and two heuristic approaches that decompose the problem into multiple single-period sub problems. The Knapsack Problem (KP), which is the first heuristic approach, solves the single period problems, using an exact MIP approach. The second heuristic approach solves the single period sub problem using a greedy heuristic approach. The three methods are compared in term of model tractability, computational time and the objective values. The model was tested using randomised data from 711 treatment units in the Barwon-Otway district of Victoria, Australia. Solutions for the exact MIP could be obtained for up to a 15-year planning only using a standard implementation of CPLEX. Both heuristic approaches can solve significantly larger problems, involving 100-year or even longer planning horizons. Furthermore there are no substantial differences in the solutions produced by the three approaches. It is concluded that for practical purposes a heuristic method is to be preferred to the exact MIP approach.

  19. When 95% Accurate Isn't: Exploring Bayes's Theorem

    ERIC Educational Resources Information Center

    CadwalladerOlsker, Todd D.

    2011-01-01

    Bayes's theorem is notorious for being a difficult topic to learn and to teach. Problems involving Bayes's theorem (either implicitly or explicitly) generally involve calculations based on two or more given probabilities and their complements. Further, a correct solution depends on students' ability to interpret the problem correctly. Most people…

  20. Semantic Structures of One-Step Word Problems Involving Multiplication or Division.

    ERIC Educational Resources Information Center

    Schmidt, Siegbert; Weiser, Werner

    1995-01-01

    Proposes a four-category classification of semantic structures of one-step word problems involving multiplication and division: forming the n-th multiple of measures, combinatorial multiplication, composition of operators, and multiplication by formula. This classification is compatible with semantic structures of addition and subtraction word…

  1. Program for Peer Relationship Development.

    ERIC Educational Resources Information Center

    Salzberg, Bernard; Smith, Nancy E.

    Children, aged 10-12, were referred to an outpatient mental health center because of behavior problems, some involving social skill deficits, others not so involved. Children acknowledging a social skill problem, and a desire to do something about it, were chosen pending parent approval and cooperation. Prior to participation in the group,…

  2. Quantitative Relationships Involving Additive Differences: Numerical Resilience

    ERIC Educational Resources Information Center

    Ramful, Ajay; Ho, Siew Yin

    2014-01-01

    This case study describes the ways in which problems involving additive differences with unknown starting quantities, constrain the problem solver in articulating the inherent quantitative relationship. It gives empirical evidence to show how numerical reasoning takes over as a Grade 6 student instantiates the quantitative relation by resorting to…

  3. Unresolved Technical Issues in Fair Interest Measurement.

    ERIC Educational Resources Information Center

    Cole, Nancy S.

    The problem of sex differences in interest measurement involves many technical issues and procedures. The purpose of this paper is to provide a description of the technical problems involved in construction, scoring, and interpretation of interest measures as related to sex differences and to suggest guidelines within these technical issues which…

  4. Growing up with adversity: From juvenile justice involvement to criminal persistence and psychosocial problems in young adulthood.

    PubMed

    Basto-Pereira, Miguel; Miranda, Ana; Ribeiro, Sofia; Maia, Ângela

    2016-12-01

    Several studies have been carried out to investigate the effect of child maltreatment on juvenile justice involvement and future criminal life. However, little is known about the impact of other forms of adversity, beyond abuse and neglect, on juvenile delinquency and criminal persistence. The effect of early adversity on psychosocial problems is underexplored, particularly in juvenile delinquents. This study, using the Childhood Adverse Experiences (ACE) questionnaire, a tool accessing the exposure to different types of abuse, neglect and serious household dysfunction, explored the role of each adverse experience on juvenile justice involvement, persistence in crime and psychosocial problems during young adulthood. A Portuguese sample of 75 young adults with official records of juvenile delinquency in 2010/2011, and 240 young adults from a community sample completed ACE questionnaire and measures of psychosocial adjustment. Seven out of ten adverse experiences were significantly more prevalent in young adults with juvenile justice involvement than in the community sample, after matching the main demographic variables. The strongest predictor of juvenile justice involvement and criminal persistence during early adulthood was sexual abuse. Dimensions of child/adolescent emotional maltreatment and a mental illness in the household predicted a set of psychosocial problems in young adulthood. This study indicates that early adversity is significantly related to juvenile justice involvement, criminal persistence and psychosocial problems. This study also suggests that each experience has a different role in this process. There is an urgent need to screen, prevent and stop serious adversity. Future scientific directions and recommendations for policies are provided. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Dystrophic changes in masticatory muscles related chewing problems and malocclusions in Duchenne muscular dystrophy.

    PubMed

    van den Engel-Hoek, L; de Groot, I J M; Sie, L T; van Bruggen, H W; de Groot, S A F; Erasmus, C E; van Alfen, N

    2016-06-01

    Dysphagia in Duchenne muscular dystrophy (DMD) worsens with age, with increasingly effortful mastication. The aims of this study were to describe mastication problems in consecutive stages in a group of patients with DMD and to determine related pathophysiological aspects of masticatory muscle structure, tongue thickness, bite force and dental characteristics. Data from 72 patients with DMD (4.3 to 28.0 years), divided into four clinical stages, were collected in a cross sectional study. Problems with mastication and the need for food adaptations, in combination with increased echogenicity of the masseter muscle, were already found in the early stages of the disease. A high percentage of open bites and cross bites were found, especially in the later stages. Tongue hypertrophy also increased over time. Increased dysfunction, reflected by increasingly abnormal echogenicity, of the masseter muscle and reduced occlusal contacts (anterior and posterior open bites) were mainly responsible for the hampered chewing. In all, this study shows the increasing involvement of various elements of the masticatory system in progressive Duchenne muscular dystrophy. To prevent choking and also nutritional deficiency, early detection of chewing problems by asking about feeding and mastication problems, as well as asking about food adaptations made, is essential and can lead to timely intervention. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Emotional, self-conceptual, and relational characteristics of bullies and the bullied.

    PubMed

    Meland, Eivind; Rydning, Jan Henrik; Lobben, Stian; Breidablik, Hans-Johan; Ekeland, Tor-Johan

    2010-06-01

    To clarify distributions of emotional and somatic symptoms among different groups involved in bullying behaviour during early adolescence; to explore differences in social integration and self-perceptions; to explore how different cut-off limits for bullying behaviour may affect the impact of these measures; and to interpret our findings in the light of theories of identity that may suggest directions for interventions against bullying in schools. A cross-sectional study, based on self-completion questionnaire, of 1237 pupils aged 11-15 years in autumn 2000 in Alesund, Norway. Bullies and their victims reported similar and greater emotional impairments and psychosomatic complaints, lack of self-confidence, and pessimism than students not involved in bullying. With increasing involvement, bullies differed from non-involved students only in regard to depressive complaints and pessimism. The bullied group reported more depressive, somatic and anxiety complaints, and self-reproach with increasing victimisation. Both bullies and the bullied reported problems relating to school, parents, and teachers. Bullies enjoyed friendships to the same degree or better than their peers not involved in bullying, whereas the bullied group reported impaired peer relations and increasing problems with more serious involvement. Bullies, the bullied, and bully-victims reported diminishing peer support in their class with increasing involvement. Both the bullied and bullies share relational, emotional, and self-conceptual problems, but they also differ in whether they succeed in social arenas and to what extent they are affected by different emotional and self-conceptual problems. They are, however, fellow sufferers in many aspects.

  7. The Developmental Costs and Benefits of Children’s Involvement in Interparental Conflict

    PubMed Central

    Davies, Patrick T.; Coe, Jesse L.; Martin, Meredith J.; Sturge-Apple, Melissa L.; Cummings, E. Mark

    2015-01-01

    Building on empirical documentation of children’s involvement in interparental conflicts as a weak predictor of psychopathology, we tested the hypothesis that involvement in conflict more consistently serves as a moderator of associations between children’s emotional reactivity to interparental conflict and their psychological problems. In Study 1, 263 early adolescents (M age = 12.62 years), mothers, and fathers completed surveys of family and child functioning at two measurement occasions spaced two years apart. In Study 2, 243 preschool children (M age = 4.60 years) participated in a multi-method (i.e., observations, structured interview, surveys) measurement battery to assess family functioning, children’s reactivity to interparental conflict, and their psychological adjustment. Across both studies, latent difference score (LDS) analyses revealed that involvement moderated associations between emotional reactivity and children’s increases in psychological (i.e., internalizing and externalizing) problems. Children’s emotional reactivity to interparental conflict was a significantly stronger predictor of their psychological maladjustment when they were highly involved in the conflicts. In addition, the developmental benefits and costs of involvement varied as a function of emotional reactivity. Involvement in interparental conflict predicted increases in psychological problems for children experiencing high emotional reactivity and decreases in psychological problems when they exhibited low emotional reactivity. We interpret the results in the context of the new formulation of emotional security theory (e.g. Davies & Martin, 2013) and family systems models of children’s parentification (e.g., Byng-Hall, 2002). PMID:26053147

  8. The developmental costs and benefits of children's involvement in interparental conflict.

    PubMed

    Davies, Patrick T; Coe, Jesse L; Martin, Meredith J; Sturge-Apple, Melissa L; Cummings, E Mark

    2015-08-01

    Building on empirical documentation of children's involvement in interparental conflicts as a weak predictor of psychopathology, we tested the hypothesis that involvement in conflict more consistently serves as a moderator of associations between children's emotional reactivity to interparental conflict and their psychological problems. In Study 1, 263 early adolescents (M age = 12.62 years), mothers, and fathers completed surveys of family and child functioning at 2 measurement occasions spaced 2 years apart. In Study 2, 243 preschool children (M age = 4.60 years) participated in a multimethod (i.e., observations, structured interview, surveys) measurement battery to assess family functioning, children's reactivity to interparental conflict, and their psychological adjustment. Across both studies, latent difference score analyses revealed that involvement moderated associations between emotional reactivity and children's increases in psychological (i.e., internalizing and externalizing) problems. Children's emotional reactivity to interparental conflict was a significantly stronger predictor of their psychological maladjustment when they were highly involved in the conflicts. In addition, the developmental benefits and costs of involvement varied as a function of emotional reactivity. Involvement in interparental conflict predicted increases in psychological problems for children experiencing high emotional reactivity and decreases in psychological problems when they exhibited low emotional reactivity. We interpret the results in the context of the new formulation of emotional security theory (e.g., Davies & Martin, 2013) and family systems models of children's parentification (e.g., Byng-Hall, 2002). (c) 2015 APA, all rights reserved).

  9. The Riemann problem for longitudinal motion in an elastic-plastic bar

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

    Trangenstein, J.A.; Pember, R.B.

    In this paper the analytical solution to the Riemann problem for the Antman-Szymczak model of longitudinal motion in an elastic-plastic bar is constructed. The model involves two surfaces corresponding to plastic yield in tension and compression, and exhibits the appropriate limiting behavior for total compressions. The solution of the Riemann problem involves discontinuous changes in characteristic speeds due to transitions from elastic to plastic response. Illustrations are presented, in both state-space and self-similar coordinates, of the variety of possible solutions to the Riemann problem for possible use with numerical algorithms.

  10. Obesity and sickness absence: results from the CHAP study.

    PubMed

    Harvey, S B; Glozier, N; Carlton, O; Mykletun, A; Henderson, M; Hotopf, M; Holland-Elliott, K

    2010-08-01

    Obesity is an increasing public health problem. A small number of studies have examined the relationship between obesity and sickness absence, with mixed results, particularly regarding short-term sickness absence. To determine if obesity is associated with short- and long-term sickness absence and to investigate the mechanisms that may underlie any association. Cross-sectional (n = 1489) and prospective (n = 625) analyses were conducted on staff from London Underground Ltd. All participants underwent regular clinical examinations that involved their height and weight being measured, obesity-related medical problems being diagnosed and psychiatric disorders being identified. The number of days taken for short- (<10 days in an episode) and long-term sickness absence were recorded by managers on an electronic database. There was a positive linear association between employees' body mass index (BMI) and the number of days' work missed due to sickness absence on both cross-sectional and prospective analyses (P < 0.001). Obesity was a risk factor for both short- and long-term sickness absence. Obese individuals typically took an extra 4 days sick leave every year. The majority of the increased risk for long-term sickness absence appeared to be mediated via co-morbid chronic medical conditions. The excess short-term sickness absence was not explained by obesity-related medical problems, psychiatric disorders or workplace factors. Obese employees take significantly more short- and long-term sickness absence than workers of a healthy weight. There is growing evidence to support employers becoming more involved in tackling obesity.

  11. Informal Payments for Health Care in Iran: Results of a Qualitative Study

    PubMed Central

    PARSA, Mojtaba; ARAMESH, Kiarash; NEDJAT, Saharnaz; KANDI, Mohammad Jafar; LARIJANI, Bagher

    2015-01-01

    Abstract Background Informal payments to health care providers have been reported in many African, Asian and European countries. This study aimed to investigate different aspects of these payments that are also known as under-the-table payments in Iran. Methods This is an in-depth interview-based qualitative study conducted on 12 purposively chosen clinical specialists. The interviewees answered 9 questions including the ones about, definitions of informal payments, the specialties and hospitals mostly involved with the problem, how they are paid, factors involved, motivation of patients for the payments, impact of the payments on the health care system and physician-patient relationship and the ways to face up with the problem. The findings of the study were analyzed using qualitative content analysis method. Results Six topics were extracted from the interviews including definitions, commonness, varieties, motivations, outcomes and preventive measures. It was revealed that under-the-table payments are the money taken (either in private or public portions) from patients in addition to what formally is determined. This problem is mostly seen in surgical services and the most important reason for it is unrealistic tariffs. Conclusion Regarding the soaring commonness of informal payments rooted in underpayments of health expenditures in some specialties, which deeply affect the poor, the government has to boost the capitation and to invest on health sectors through supporting the health insurance companies and actualizing the health care costs in accord with the real price of the health care delivered. PMID:26060779

  12. Crossover ensembles of random matrices and skew-orthogonal polynomials

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

    Kumar, Santosh, E-mail: skumar.physics@gmail.com; Pandey, Akhilesh, E-mail: ap0700@mail.jnu.ac.in

    2011-08-15

    Highlights: > We study crossover ensembles of Jacobi family of random matrices. > We consider correlations for orthogonal-unitary and symplectic-unitary crossovers. > We use the method of skew-orthogonal polynomials and quaternion determinants. > We prove universality of spectral correlations in crossover ensembles. > We discuss applications to quantum conductance and communication theory problems. - Abstract: In a recent paper (S. Kumar, A. Pandey, Phys. Rev. E, 79, 2009, p. 026211) we considered Jacobi family (including Laguerre and Gaussian cases) of random matrix ensembles and reported exact solutions of crossover problems involving time-reversal symmetry breaking. In the present paper we givemore » details of the work. We start with Dyson's Brownian motion description of random matrix ensembles and obtain universal hierarchic relations among the unfolded correlation functions. For arbitrary dimensions we derive the joint probability density (jpd) of eigenvalues for all transitions leading to unitary ensembles as equilibrium ensembles. We focus on the orthogonal-unitary and symplectic-unitary crossovers and give generic expressions for jpd of eigenvalues, two-point kernels and n-level correlation functions. This involves generalization of the theory of skew-orthogonal polynomials to crossover ensembles. We also consider crossovers in the circular ensembles to show the generality of our method. In the large dimensionality limit, correlations in spectra with arbitrary initial density are shown to be universal when expressed in terms of a rescaled symmetry breaking parameter. Applications of our crossover results to communication theory and quantum conductance problems are also briefly discussed.« less

  13. Digitalizing historical high resolution water level data: Challenges and opportunities

    NASA Astrophysics Data System (ADS)

    Holinde, Lars; Hein, Hartmut; Barjenbruch, Ulrich

    2017-04-01

    Historical tide-gauge data offer the opportunities for determining variations in key characteristics for water level data and the analyses of past extreme events (storm surges). These information are important for calculating future trends and scenarios. But there are challenges involved due to the extensive effort needed to digitalize gauge sheets and quality control the resulting historical data. Based on these conditions, two main sources for inaccuracies in historical time series can be identified. First are several challenges due to the digitalization of the historical data, e.g. general quality of the sheets, multiple crossing lines of the observed water levels and additional comments on the sheet describing problems or additional information during the measurements. Second are problems during the measurements themselves. These can include the incorrect positioning of the sheets, trouble with the tide-gauge and maintenance. Errors resulting from these problems can be e.g. flat lines, discontinuities and outlier. Especially, the characterization of outliers has to be conducted carefully, to distinguish between real outliers and the appearance of extreme events. Methods for the quality control process involve the use of statistics, machine learning and neural networks. These will be described and applied to three different time series from tide gauge stations at the cost of Lower Saxony, Germany. Resulting difficulties and outcomes of the quality control process will be presented and explained. Furthermore, we will present a first glance at analyses for these time series.

  14. Individualized Math Problems in Ratio and Proportion. Oregon Vo-Tech Mathematics Problem Sets.

    ERIC Educational Resources Information Center

    Cosler, Norma, Ed.

    This is one of eighteen sets of individualized mathematics problems developed by the Oregon Vo-Tech Math Project. Each of these problem packages is organized around a mathematical topic and contains problems related to diverse vocations. Solutions are provided for all problems. This volume contains problems involving ratio and proportion. Some…

  15. Individualized Math Problems in Whole Numbers. Oregon Vo-Tech Mathematics Problem Sets.

    ERIC Educational Resources Information Center

    Cosler, Norma, Ed.

    This is one of eighteen sets of individualized mathematics problems developed by the Oregon Vo-Tech Math Project. Each of these problem packages is organized around a mathematical topic and contains problems related to diverse vocations. Solutions are provided for all problems. Problems in this set require computations involving whole numbers.…

  16. Individualized Math Problems in Graphs and Tables. Oregon Vo-Tech Mathematics Problem Sets.

    ERIC Educational Resources Information Center

    Cosler, Norma, Ed.

    This is one of eighteen sets of individualized mathematics problems developed by the Oregon Vo-Tech Math Project. Each of these problem packages is organized around a mathematical topic and contains problems related to diverse vocations. Solutions are provided for all problems. Problems involving the construction and interpretation of graphs and…

  17. Distributed query plan generation using multiobjective genetic algorithm.

    PubMed

    Panicker, Shina; Kumar, T V Vijay

    2014-01-01

    A distributed query processing strategy, which is a key performance determinant in accessing distributed databases, aims to minimize the total query processing cost. One way to achieve this is by generating efficient distributed query plans that involve fewer sites for processing a query. In the case of distributed relational databases, the number of possible query plans increases exponentially with respect to the number of relations accessed by the query and the number of sites where these relations reside. Consequently, computing optimal distributed query plans becomes a complex problem. This distributed query plan generation (DQPG) problem has already been addressed using single objective genetic algorithm, where the objective is to minimize the total query processing cost comprising the local processing cost (LPC) and the site-to-site communication cost (CC). In this paper, this DQPG problem is formulated and solved as a biobjective optimization problem with the two objectives being minimize total LPC and minimize total CC. These objectives are simultaneously optimized using a multiobjective genetic algorithm NSGA-II. Experimental comparison of the proposed NSGA-II based DQPG algorithm with the single objective genetic algorithm shows that the former performs comparatively better and converges quickly towards optimal solutions for an observed crossover and mutation probability.

  18. Distributed Query Plan Generation Using Multiobjective Genetic Algorithm

    PubMed Central

    Panicker, Shina; Vijay Kumar, T. V.

    2014-01-01

    A distributed query processing strategy, which is a key performance determinant in accessing distributed databases, aims to minimize the total query processing cost. One way to achieve this is by generating efficient distributed query plans that involve fewer sites for processing a query. In the case of distributed relational databases, the number of possible query plans increases exponentially with respect to the number of relations accessed by the query and the number of sites where these relations reside. Consequently, computing optimal distributed query plans becomes a complex problem. This distributed query plan generation (DQPG) problem has already been addressed using single objective genetic algorithm, where the objective is to minimize the total query processing cost comprising the local processing cost (LPC) and the site-to-site communication cost (CC). In this paper, this DQPG problem is formulated and solved as a biobjective optimization problem with the two objectives being minimize total LPC and minimize total CC. These objectives are simultaneously optimized using a multiobjective genetic algorithm NSGA-II. Experimental comparison of the proposed NSGA-II based DQPG algorithm with the single objective genetic algorithm shows that the former performs comparatively better and converges quickly towards optimal solutions for an observed crossover and mutation probability. PMID:24963513

  19. Mixed integer simulation optimization for optimal hydraulic fracturing and production of shale gas fields

    NASA Astrophysics Data System (ADS)

    Li, J. C.; Gong, B.; Wang, H. G.

    2016-08-01

    Optimal development of shale gas fields involves designing a most productive fracturing network for hydraulic stimulation processes and operating wells appropriately throughout the production time. A hydraulic fracturing network design-determining well placement, number of fracturing stages, and fracture lengths-is defined by specifying a set of integer ordered blocks to drill wells and create fractures in a discrete shale gas reservoir model. The well control variables such as bottom hole pressures or production rates for well operations are real valued. Shale gas development problems, therefore, can be mathematically formulated with mixed-integer optimization models. A shale gas reservoir simulator is used to evaluate the production performance for a hydraulic fracturing and well control plan. To find the optimal fracturing design and well operation is challenging because the problem is a mixed integer optimization problem and entails computationally expensive reservoir simulation. A dynamic simplex interpolation-based alternate subspace (DSIAS) search method is applied for mixed integer optimization problems associated with shale gas development projects. The optimization performance is demonstrated with the example case of the development of the Barnett Shale field. The optimization results of DSIAS are compared with those of a pattern search algorithm.

  20. Environmental health and hazardous waste issues related to the U.S.-Mexico border.

    PubMed Central

    Carter, D E; Peña, C; Varady, R; Suk, W A

    1996-01-01

    Environmental health and environmental quality issues along the U.S.-Mexico border have been of concern for several years. The enactment of the North American Free Trade Agreement and the presence of the maquiladoras (foreign-owned industries using imported raw materials) have intensified those concerns recently. Efforts to assess these issues are complicated by the fact that many of the issues affecting the border region are within federal jurisdiction, but the problems are regional and local in nature. Thus, state and local governments become involved with public concerns about real and potential problems. One major problem is that environmental health data from this region are lacking, particularly from Mexico. Some new agencies such as the Border Environment Cooperation Commission, the United States-Mexico Border Health Commission, and the North American Commission on Environmental Cooperation have joined several existing agencies at the federal and state level to address environmental quality and health. Several studies have been initiated to determine air and water quality, but little is being done in the areas of hazardous waste and health assessment. Several problems are anticipated in the generation of such data, such as its format and accessibility. Data gaps and research needs are discussed. PMID:8793340

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

    NASA Astrophysics Data System (ADS)

    Biswas, Parthapratim; Drabold, David; Elliott, Stephen

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

  2. Calculating complete and exact Pareto front for multiobjective optimization: a new deterministic approach for discrete problems.

    PubMed

    Hu, Xiao-Bing; Wang, Ming; Di Paolo, Ezequiel

    2013-06-01

    Searching the Pareto front for multiobjective optimization problems usually involves the use of a population-based search algorithm or of a deterministic method with a set of different single aggregate objective functions. The results are, in fact, only approximations of the real Pareto front. In this paper, we propose a new deterministic approach capable of fully determining the real Pareto front for those discrete problems for which it is possible to construct optimization algorithms to find the k best solutions to each of the single-objective problems. To this end, two theoretical conditions are given to guarantee the finding of the actual Pareto front rather than its approximation. Then, a general methodology for designing a deterministic search procedure is proposed. A case study is conducted, where by following the general methodology, a ripple-spreading algorithm is designed to calculate the complete exact Pareto front for multiobjective route optimization. When compared with traditional Pareto front search methods, the obvious advantage of the proposed approach is its unique capability of finding the complete Pareto front. This is illustrated by the simulation results in terms of both solution quality and computational efficiency.

  3. Lessons Learned from Decontamination Experiences

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

    Sorensen, JH

    2000-11-16

    This interim report describes a DOE project currently underway to establish what is known about decontamination of buildings and people and the procedures and protocols used to determine when and how people or buildings are considered ''clean'' following decontamination. To fulfill this objective, the study systematically examined reported decontamination experiences to determine what procedures and protocols are currently employed for decontamination, the timeframe involved to initiate and complete the decontamination process, how the contaminants were identified, the problems encountered during the decontamination process, how response efforts of agencies were coordinated, and the perceived social psychological effects on people who weremore » decontaminated or who participated in the decontamination process. Findings and recommendations from the study are intended to aid decision-making and to improve the basis for determining appropriate decontamination protocols for recovery planners and policy makers for responding to chemical and biological events.« less

  4. Characterization of urania vaporization with transpiration coupled thermogravimetry

    DOE PAGES

    McMurray, J. W.

    2015-12-05

    Determining equilibrium vapor pressures of materials is made easier by transpiration measurements. However, the traditional technique involves condensing the volatiles entrained in a carrier gas outside of the hot measurement zone. One potential problem is deposition en route to a cooled collector. Thermogravimetric analysis (TGA) can be used to measure in situ mass loss due to vaporization and therefore obviate the need to analyze the entire gas train due to premature plating of vapor species. Therefore, a transpiration coupled TGA technique was used to determine equilibrium pressures of UO3 gas over fluorite structure UO2+x and U3O8 at T = (1573more » and 1773) K. Moreover, we compared to calculations from models and databases in the open literature. Our study gives clarity to the thermochemical data for UO3 gas and validates the mass loss transpiration method using thermogravimetry for determining equilibrium vapor pressures of non-stoichiometric oxides.« less

  5. Comparison of NAVSTAR satellite L band ionospheric calibrations with Faraday rotation measurements

    NASA Technical Reports Server (NTRS)

    Royden, H. N.; Miller, R. B.; Buennagel, L. A.

    1984-01-01

    It is pointed out that interplanetary navigation at the Jet Propulsion Laboratory (JPL) is performed by analyzing measurements derived from the radio link between spacecraft and earth and, near the target, onboard optical measurements. For precise navigation, corrections for ionospheric effects must be applied, because the earth's ionosphere degrades the accuracy of the radiometric data. These corrections are based on ionospheric total electron content (TEC) determinations. The determinations are based on the measurement of the Faraday rotation of linearly polarized VHF signals from geostationary satellites. Problems arise in connection with the steadily declining number of satellites which are suitable for Faraday rotation measurements. For this reason, alternate methods of determining ionospheric electron content are being explored. One promising method involves the use of satellites of the NAVSTAR Global Positioning System (GPS). The results of a comparative study regarding this method are encouraging.

  6. On the tandem Morita-Baylis-Hillman/transesterification processes. Mechanistic insights for the role of protic solvents

    NASA Astrophysics Data System (ADS)

    Carpanez, Arthur G.; Coelho, Fernando; Amarante, Giovanni W.

    2018-02-01

    Despite the remarkable rate acceleration under protic solvents such as alcohols and water, the use of acrylates as activated alkenes places a problem due to the possibility of ester hydrolysis or transesterification. Therefore, the tandem transesterification/Morita-Baylis-Hillman (MBH) reactions were investigated by ESI(+)-MS/(MS) and 1H NMR techniques. For the first time, the MBH back-reaction was fully examined by ESI(+)-MS/(MS) using labelling reagents revealed the complex equilibrium involving the Michael-type addition step of DABCO to acrylate. C- and O-protonation were observed at this stage, showing the transesterification process occurs previous to the aldol step, which is the rate-determining step of the mechanism. At this stage, a short-lived tetrahedral intermediate might be involved and should be considered in these processes.

  7. Fluorescent antibody detection of microorganisms in terrestrial environments

    NASA Technical Reports Server (NTRS)

    Schmidt, E. L.

    1972-01-01

    The fluorescent antibody technique and its use in direct microscopic examination of the soil is discussed. Feasibility analyses were made to determine if the method could be used to simultaneously observe and recognize microorganisms in the soil. Some data indicate this may be possible. Data are also given on two related problems involving the interaction of soil microorganisms with plant roots to form symbiotic structures. One was concerned with the developmental ecology and biology of the root nodule of alder and the second was concerned with the ectotrophic mycorrhizal structure on forest trees, especially pines. In both, the fluorescent antibody detection of the microbial symbiont both as a free living form in soil, and as a root inhabiting form in the higher plant was emphasized. A third aspect of the research involved the detection of autotrophic ammonia oxidizing microorganisms in soil.

  8. An integral transform approach for a mixed boundary problem involving a flowing partially penetrating well with infinitesimal well skin

    NASA Astrophysics Data System (ADS)

    Chang, Chien-Chieh; Chen, Chia-Shyun

    2002-06-01

    A flowing partially penetrating well with infinitesimal well skin is a mixed boundary because a Cauchy condition is prescribed along the screen length and a Neumann condition of no flux is stipulated over the remaining unscreened part. An analytical approach based on the integral transform technique is developed to determine the Laplace domain solution for such a mixed boundary problem in a confined aquifer of finite thickness. First, the mixed boundary is changed into a homogeneous Neumann boundary by substituting the Cauchy condition with a Neumann condition in terms of well bore flux that varies along the screen length and is time dependent. Despite the well bore flux being unknown a priori, the modified model containing this homogeneous Neumann boundary can be solved with the Laplace and the finite Fourier cosine transforms. To determine well bore flux, screen length is discretized into a finite number of segments, to which the Cauchy condition is reinstated. This reinstatement also restores the relation between the original model and the solutions obtained. For a given time, the numerical inversion of the Laplace domain solution yields the drawdown distributions, well bore flux, and the well discharge. This analytical approach provides an alternative for dealing with the mixed boundary problems, especially when aquifer thickness is assumed to be finite.

  9. Fast Algorithms for Structured Least Squares and Total Least Squares Problems

    PubMed Central

    Kalsi, Anoop; O’Leary, Dianne P.

    2006-01-01

    We consider the problem of solving least squares problems involving a matrix M of small displacement rank with respect to two matrices Z1 and Z2. We develop formulas for the generators of the matrix M HM in terms of the generators of M and show that the Cholesky factorization of the matrix M HM can be computed quickly if Z1 is close to unitary and Z2 is triangular and nilpotent. These conditions are satisfied for several classes of matrices, including Toeplitz, block Toeplitz, Hankel, and block Hankel, and for matrices whose blocks have such structure. Fast Cholesky factorization enables fast solution of least squares problems, total least squares problems, and regularized total least squares problems involving these classes of matrices. PMID:27274922

  10. Fast Algorithms for Structured Least Squares and Total Least Squares Problems.

    PubMed

    Kalsi, Anoop; O'Leary, Dianne P

    2006-01-01

    We consider the problem of solving least squares problems involving a matrix M of small displacement rank with respect to two matrices Z 1 and Z 2. We develop formulas for the generators of the matrix M (H) M in terms of the generators of M and show that the Cholesky factorization of the matrix M (H) M can be computed quickly if Z 1 is close to unitary and Z 2 is triangular and nilpotent. These conditions are satisfied for several classes of matrices, including Toeplitz, block Toeplitz, Hankel, and block Hankel, and for matrices whose blocks have such structure. Fast Cholesky factorization enables fast solution of least squares problems, total least squares problems, and regularized total least squares problems involving these classes of matrices.

  11. Toddler run-overs--a persistent problem.

    PubMed

    Byard, Roger W; Jensen, Lisbeth L

    2009-05-01

    Trauma accounts for a high percentage of unexpected deaths in toddlers and young children, mostly due to vehicle accidents, drowning and fires. Given recent efforts to publicise the dangers of toddler run-overs a study was undertaken to determine how significant this problem remains in South Australia. Review of coronial files over 7 years from 2000 to 2006 revealed 50 cases of sudden and unexpected death in children aged between 1 and 3 years of which 12 of 28 accidents involved motor vehicles (6 run-overs and 6 passengers). The 6 children who were killed by vehicle run-overs were aged from 12 months to 22 months (ave=16.8 months) with a male to female ratio of 1:1. Four deaths occurred with reversing vehicles in home driveways and one at a community centre. The remaining death involved a child being run over at the beach by a forward moving vehicle. Vehicles included sedans in four cases and a four-wheel drive in one case (one vehicle was not described), and were driven by the victim's parent in four cases, a friend of the family in one, and an unrelated person in the final case. Deaths were all due to blunt cranial trauma. Despite initiatives to prevent these deaths, toddler run-overs in South Australia approximate the number of sudden deaths due to homicides, drownings and natural diseases, respectively, for the same age group; deaths are also occurring in places other than home driveways, and sedans were more often involved than four-wheel drive vehicles.

  12. The New Workforce Generation: Understanding the Problems Facing Parental Involvement in Jordanian Kindergartens

    ERIC Educational Resources Information Center

    Ihmeideh, Fathi; Khasawneh, Samer; Mahfouz, Safi; Khawaldeh, Moustafa

    2008-01-01

    This study aimed to investigate the problems facing parental involvement in Jordanian kindergartens from the parents' perspectives. A 36-item questionnaire that addressed five domains was designed by the researchers and distributed among the study participants. The study sample consisted of 297 parents of kindergarten children from various…

  13. Concurrent Mental Health and Substance Use Problems among Street-Involved Youth

    ERIC Educational Resources Information Center

    Kirst, Maritt; Frederick, Tyler; Erickson, Patricia G.

    2011-01-01

    Among marginalized populations, homeless adults are known to have elevated rates of mental health and substance use problems compared to the general population, but less is known about their youthful homeless counterparts. While few studies currently exist, what research has been conducted among street-involved youth has confirmed high rates of…

  14. Systematic Approach to Calculate the Concentration of Chemical Species in Multi-Equilibrium Problems

    ERIC Educational Resources Information Center

    Baeza-Baeza, Juan Jose; Garcia-Alvarez-Coque, Maria Celia

    2011-01-01

    A general systematic approach is proposed for the numerical calculation of multi-equilibrium problems. The approach involves several steps: (i) the establishment of balances involving the chemical species in solution (e.g., mass balances, charge balance, and stoichiometric balance for the reaction products), (ii) the selection of the unknowns (the…

  15. Blaming the Victim: The Problem of Evaluation Design and Federal Involvement, and Reinforcing World Views in Education.

    ERIC Educational Resources Information Center

    Fetterman, David M.

    1981-01-01

    Shows how evaluation design and federal involvement in Youth Employment Demonstration Projects unintentionally cause a negative appraisal. Indicates the problem stems from interaction of the contract research corporation, the educational research establishment, and the federal bureaucracy, rather than a specific methodology or bureaucratic…

  16. Psychological problems, protective factors and health-related quality of life in youth affected by violence: the burden of the multiply victimised.

    PubMed

    Schlack, Robert; Ravens-Sieberer, Ulrike; Petermann, Franz

    2013-06-01

    This study investigates self-rated mental health in terms of psychological problems, protective factors and health-related quality of life (HRQOL) in a nationally representative sample of adolescents (n=6813) aged 11-17 involved in violence with varying frequency. Using MANCOVA and ANCOVA, youth with single and multiple histories of violent victimisation and violence perpetration were contrasted with non-involved comparisons. The results show that even low levels of violence involvement were associated with more problems, fewer protective factors and impaired HRQOL. Multiply victimised youth - not perpetrating victims - stood out with internalising, peer and hyperactivity/inattention problems. Discriminant function analysis separated non-involved from violence-affected youth, and multiply victimised from not multiply victimised youth. Externalising behaviours, family issues, male sex and school functioning predicted group separation on the first function (proportion variance explained 80.0%), while internalising and peer issues were predictive for the second function (PVE 14.2%). Implications for prevention, intervention and research are discussed. Copyright © 2013 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

  17. Examining gender differences for gambling engagement and gambling problems among emerging adults.

    PubMed

    Wong, Gloria; Zane, Nolan; Saw, Anne; Chan, Alan Ka Ki

    2013-06-01

    Gambling is fast becoming a public health problem in the United States, especially among emerging adults (18-25 year olds). Since 1995, rates have recently doubled with around 7-11 % of the emerging adult population having problems with gambling (Shaffer et al. in Am J Public Health 89(9):1369-1376, 1999; Cyders and Smith in Pers Individ Diff 45(6):503-508, 2008). Some states have lowered their gambling age to 18 years old; in turn, the gambling industry has recently oriented their market to target this younger population. However, little is known about the gender variation and the factors placing emerging adults at risk for getting engaged and developing problems with gambling. The purpose of the study was to determine the risk factors accounting for gender differences at the two levels of gambling involvement: engagement and problems. Mediation analyses revealed that impulsive coping and risk-taking were significant partial mediators for gender differences on engagement in gambling. Men took more risks and had lower levels of impulsive coping than women, and those who took more risks and had lower levels of impulsive coping were more likely to engage in gambling. Risk-taking and social anxiety were the significant mediators for gender differences in problems with gambling. Men took more risks and were more socially anxious than women, and greater risk-taking and more socially anxious individuals tended to have more problems with gambling. Implications for counseling preventions and intervention strategies are discussed.

  18. A toolbox and record for scientific models

    NASA Technical Reports Server (NTRS)

    Ellman, Thomas

    1994-01-01

    Computational science presents a host of challenges for the field of knowledge-based software design. Scientific computation models are difficult to construct. Models constructed by one scientist are easily misapplied by other scientists to problems for which they are not well-suited. Finally, models constructed by one scientist are difficult for others to modify or extend to handle new types of problems. Construction of scientific models actually involves much more than the mechanics of building a single computational model. In the course of developing a model, a scientist will often test a candidate model against experimental data or against a priori expectations. Test results often lead to revisions of the model and a consequent need for additional testing. During a single model development session, a scientist typically examines a whole series of alternative models, each using different simplifying assumptions or modeling techniques. A useful scientific software design tool must support these aspects of the model development process as well. In particular, it should propose and carry out tests of candidate models. It should analyze test results and identify models and parts of models that must be changed. It should determine what types of changes can potentially cure a given negative test result. It should organize candidate models, test data, and test results into a coherent record of the development process. Finally, it should exploit the development record for two purposes: (1) automatically determining the applicability of a scientific model to a given problem; (2) supporting revision of a scientific model to handle a new type of problem. Existing knowledge-based software design tools must be extended in order to provide these facilities.

  19. Epidemiology of pediatric burns and future prevention strategies-a study of 475 patients from a high-volume burn center in North India.

    PubMed

    Dhopte, Amol; Tiwari, V K; Patel, Pankaj; Bamal, Rahul

    2017-01-01

    Pediatric burns have a long-term social impact. This is more apparent in a developing country such as India, where their incidence and morbidity are high. The aim of this study was to provide recent prospective epidemiological data on pediatric burns in India and to suggest future preventive strategies. Children up to 18 years old admitted to the Department of Burns, Plastic & Maxillofacial Surgery, VMMC & Safdarjung Hospital, New Delhi, between January and December 2014 were included in the study. Data regarding age, sex, etiology, total body surface area (TBSA), circumstances of injury, and clinical assessment were collected. The Mann-Whitney test or Kruskal-Wallis test or ANOVA was used to compare involved TBSA among various cohort groups accordingly. Univariate and multivariate linear regression analyses were used to determine the predictors of TBSA. There were a total of 475 patients involved in the study, including seven suicidal burns, all of whom were females with a mean age greater than the cohort average. Age, type of burns, mode of injury, presence or absence of inhalation injury, gender, and time of year (quarter) for admission were found to independently affect the TBSA involved. Electrical burns also formed an important number of presenting burn patients, mainly involving teenagers. Several societal issues have come forth, e.g., child marriage, child labor, and likely psychological problems among female children as suggested by a high incidence of suicidal burns. This study also highlights several issues such as overcrowding, lack of awareness, dangerous cooking practices, and improper use of kerosene oil. There is an emergent need to recognize the problems, formulate strategies, spread awareness, and ban or replace hazardous substances responsible for most burn accidents.

  20. Cortico-basal ganglia networks subserving goal-directed behavior mediated by conditional visuo-goal association

    PubMed Central

    Hoshi, Eiji

    2013-01-01

    Action is often executed according to information provided by a visual signal. As this type of behavior integrates two distinct neural representations, perception and action, it has been thought that identification of the neural mechanisms underlying this process will yield deeper insights into the principles underpinning goal-directed behavior. Based on a framework derived from conditional visuomotor association, prior studies have identified neural mechanisms in the dorsal premotor cortex (PMd), dorsolateral prefrontal cortex (dlPFC), ventrolateral prefrontal cortex (vlPFC), and basal ganglia (BG). However, applications resting solely on this conceptualization encounter problems related to generalization and flexibility, essential processes in executive function, because the association mode involves a direct one-to-one mapping of each visual signal onto a particular action. To overcome this problem, we extend this conceptualization and postulate a more general framework, conditional visuo-goal association. According to this new framework, the visual signal identifies an abstract behavioral goal, and an action is subsequently selected and executed to meet this goal. Neuronal activity recorded from the four key areas of the brains of monkeys performing a task involving conditional visuo-goal association revealed three major mechanisms underlying this process. First, visual-object signals are represented primarily in the vlPFC and BG. Second, all four areas are involved in initially determining the goals based on the visual signals, with the PMd and dlPFC playing major roles in maintaining the salience of the goals. Third, the cortical areas play major roles in specifying action, whereas the role of the BG in this process is restrictive. These new lines of evidence reveal that the four areas involved in conditional visuomotor association contribute to goal-directed behavior mediated by conditional visuo-goal association in an area-dependent manner. PMID:24155692

  1. Hyperbolic heat conduction problems involving non-Fourier effects - Numerical simulations via explicit Lax-Wendroff/Taylor-Galerkin finite element formulations

    NASA Technical Reports Server (NTRS)

    Tamma, Kumar K.; Namburu, Raju R.

    1989-01-01

    Numerical simulations are presented for hyperbolic heat-conduction problems that involve non-Fourier effects, using explicit, Lax-Wendroff/Taylor-Galerkin FEM formulations as the principal computational tool. Also employed are smoothing techniques which stabilize the numerical noise and accurately predict the propagating thermal disturbances. The accurate capture of propagating thermal disturbances at characteristic time-step values is achieved; numerical test cases are presented which validate the proposed hyperbolic heat-conduction problem concepts.

  2. Introducing soft systems methodology plus (SSM+): why we need it and what it can contribute.

    PubMed

    Braithwaite, Jeffrey; Hindle, Don; Iedema, Rick; Westbrook, Johanna I

    2002-01-01

    There are many complicated and seemingly intractable problems in the health care sector. Past ways to address them have involved political responses, economic restructuring, biomedical and scientific studies, and managerialist or business-oriented tools. Few methods have enabled us to develop a systematic response to problems. Our version of soft systems methodology, SSM+, seems to improve problem solving processes by providing an iterative, staged framework that emphasises collaborative learning and systems redesign involving both technical and cultural fixes.

  3. Family Environment, Coping, and Mental Health in Adolescents Attending Therapeutic Day Schools

    PubMed Central

    Rodriguez, Erin M.; Donenberg, Geri R.; Emerson, Erin; Wilson, Helen W.; Brown, Larry K.; Houck, Christopher

    2014-01-01

    OBJECTIVE This study examined associations among family environment, coping, and emotional and conduct problems in adolescents attending therapeutic day schools due to mental health problems. METHODS Adolescents (N=417; 30.2% female) ages 13–20 (M=15.25) reported on their family environment (affective involvement and functioning), coping (emotion-focused support-seeking, cognitive restructuring, avoidant actions), and emotional and conduct problems. RESULTS Poorer family environment was associated with less emotion-focused support-seeking and cognitive restructuring, and more emotional and conduct problems. Emotional problems were negatively associated with cognitive restructuring, and conduct problems were negatively associated with all coping strategies. Cognitive restructuring accounted for the relationship between family environment and emotional problems. Cognitive restructuring and emotion-focused support-seeking each partially accounted for the relationship between family functioning and conduct problems, but not the relationship between family affective involvement and conduct problems. CONCLUSIONS Findings implicate the role of coping in the relationship between family environment and adolescent mental health. PMID:25151645

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

    Vogt

    This report describes a U.S. Department of Energy, (DOE) Chemical and Biological National Security Program project that sought to establish what is known about decontamination of structures, objects, and people following an exposure to chemical or biological materials. Specifically we sought to identify the procedures and protocols used to determine when and how people or buildings are considered ''clean'' following decontamination. To fulfill this objective, the study systematically examined reported decontamination experiences to determine what procedures and protocols are currently employed for decontamination, the timeframe involved to initiate and complete the decontamination process, how the contaminants were identified, the factorsmore » determining when people were (or were not) decontaminated, the problems encountered during the decontamination process, how response efforts of agencies were coordinated, and the perceived social psychological effects on people who were decontaminated or who participated in the decontamination process. Findings and recommendations from the study are intended to aid decision-making and to improve the basis for determining appropriate decontamination protocols for recovery planners and policy makers for responding to chemical and biological events.« less

  5. Mathematical Modelling in the Early School Years

    ERIC Educational Resources Information Center

    English, Lyn D.; Watters, James J.

    2005-01-01

    In this article we explore young children's development of mathematical knowledge and reasoning processes as they worked two modelling problems (the "Butter Beans Problem" and the "Airplane Problem"). The problems involve authentic situations that need to be interpreted and described in mathematical ways. Both problems include tables of data,…

  6. Extracurricular activity participation moderates impact of family and school factors on adolescents' disruptive behavioural problems.

    PubMed

    Driessens, Corine M E F

    2015-11-11

    The prevalence of problem behaviours among British adolescents has increased in the past decades. Following Erikson's psychosocial developmental theory and Bronfenbrenner's developmental ecological model, it was hypothesized that youth problem behaviour is shaped in part by social environment. The aim of this project was to explore potential protective factors within the social environment of British youth's for the presentation of disruptive behavioural problems. This study used secondary data from the Longitudinal Study of Young People in England, a cohort study of secondary school students. These data were analysed with generalized estimation equations to take the correlation between the longitudinal observations into account. Three models were built. The first model determined the effect of family, school, and extracurricular setting on presentation of disruptive behavioural problems. The second model expanded the first model by assuming extracurricular activities as protective factors that moderated the interaction between family and school factors with disruptive behavioural problems. The third model described the effect of prior disruptive behaviour on current disruptive behaviour. Associations were found between school factors, family factors, involvement in extracurricular activities and presence of disruptive behavioural problems. Results from the second generalized estimating equation (GEE) logistic regression models indicated that extracurricular activities buffered the impact of school and family factors on the presence of disruptive behavioural problems. For instance, participation in sports activities decreased the effect of bullying on psychological distress. Results from the third model indicated that prior acts of disruptive behaviour reinforced current disruptive behaviour. This study supports Erikson's psychosocial developmental theory and Bronfenbrenner's developmental ecological model; social environment did influence the presence of disruptive behavioural problems for British adolescents. The potential of extracurricular activities to intervention strategies addressing disruptive behavioural problems of adolescents is discussed.

  7. Is there a role for a test controller in the development of new ATC equipment?

    NASA Technical Reports Server (NTRS)

    Westrum, Ron

    1994-01-01

    Earl Wiener points out that human factors problems fixed during the R & D stage are paid for once. When they are not fixed during R & D, they are then paid for every day. How users are involved in the R & D process to assist in developing equipment is a critical issue. Effective involvement can produce real improvements. Ineffective involvement can produce inefficient kludges or systems that are actually dangerous. The underlying problem is the management of information and ideas. To develop a really generative system a great deal would have to change in the way that the FAA innovates. Use of test controllers would solve only some of the problems. For instance, we have cockpit resource management now for pilots; we may have it soon for controllers. But the management of ideas in the innovation process also needs intellectual resource management. Simply involving users is not enough. Brought in at the wrong point in the development process, users can block or compromise innovation. User involvement must be carefully considered. A test controller may be one solution to this problem. It might be necessary to have several kinds of test controllers (en route versus TRACON, for instance). No doubt further problems would surface in getting test controllers into operation. I would recommend that the FAA engage in a series of case studies of controller involvement in the innovation process. A systematic comparison of effective and ineffective cases would do much to clarify what we ought to do in the future. Unfortunately, I have been unable to find any cases where test controllers have been used. Perhaps we need to create some, to see how they work.

  8. Quarantine constraints as applied to satellites

    NASA Technical Reports Server (NTRS)

    Hoffman, A. R.; Stavro, W.; Gonzalez, C. C.

    1973-01-01

    Plans for unmanned missions to planets beyond Mars in the 1970s include satellite encounters. Recently published observations of data for Titan, a satellite of Saturn, indicate that conditions may be hospitable for the growth of microorganisms. Therefore, the problem of satisfying possible quarantine constraints for outer planet satellites was investigated. This involved determining the probability of impacting a satellite of Jupiter or Saturn by a spacecraft for a planned satellite encounter during an outer planet mission. Mathematical procedures were formulated which determine the areas in the aim-plane that would result in trajectories that impact the satellite and provide a technique for numerically integrating the navigation error function over the impact area to obtain impact probabilities. The results indicate which of the planned spacecraft trajectory correction maneuvers are most critical in terms of satellite quarantine violation.

  9. A Comparative Study of Measuring Devices Used During Space Shuttle Processing for Inside Diameters

    NASA Technical Reports Server (NTRS)

    Rodriguez, Antonio

    2006-01-01

    During Space Shuttle processing, discrepancies between vehicle dimensions and per print dimensions determine if a part should be refurbished, replaced or accepted "as-is." The engineer's job is to address each discrepancy by choosing the most accurate procedure and tool available, sometimes with up to ten thousands of an inch tolerance. Four methods of measurement are commonly used at the Kennedy Space Center: 1) caliper, 2) mold impressions, 3) optical comparator, 4) dial bore gage. During a problem report evaluation, uncertainty arose between methods after measuring diameters with variations of up to 0.0004" inches. The results showed that computer based measuring devices are extremely accurate, but when human factor is involved in determining points of reference, the results may vary widely compared to more traditional methods. iv

  10. Estimating economic thresholds for pest control: an alternative procedure.

    PubMed

    Ramirez, O A; Saunders, J L

    1999-04-01

    An alternative methodology to determine profit maximizing economic thresholds is developed and illustrated. An optimization problem based on the main biological and economic relations involved in determining a profit maximizing economic threshold is first advanced. From it, a more manageable model of 2 nonsimultaneous reduced-from equations is derived, which represents a simpler but conceptually and statistically sound alternative. The model recognizes that yields and pest control costs are a function of the economic threshold used. Higher (less strict) economic thresholds can result in lower yields and, therefore, a lower gross income from the sale of the product, but could also be less costly to maintain. The highest possible profits will be obtained by using the economic threshold that results in a maximum difference between gross income and pest control cost functions.

  11. Optical properties of porous polylactide scaffolds

    NASA Astrophysics Data System (ADS)

    Yusupov, Vladimir I.; Sviridov, Alexander P.; Zhigarkov, Vyacheslav S.; Shubnyy, Andrey G.; Vorobieva, Nataliya N.; Churbanov, Semyon N.; Minaev, Nikita V.; Timashev, Peter S.; Rochev, Yury A.; Bagratashvili, Victor N.

    2018-04-01

    Light field intensity distribution in three-dimensional polylactide scaffolds after irradiation with low-intensity light from one side of the samples has been determined in the visible and near-infrared regions of the spectrum. Two different types of scaffolds manufactured by the methods of supercritical fluid foaming and surface selective laser sintering have been investigated. The problem is solved by numerical calculation according to the Monte Carlo method involving experimentally obtained information about effective optical parameters of the scaffold material. Information about intensity distribution of the incident light in the matrix volume is needed to assess the radiation level for the scaffold cells after photobiostimulation. It has been shown that the formation of the light field in case of strongly scattering media, such as polylactide scaffolds, is determined by anisotropy g and the scattering coefficient μs.

  12. A Projection free method for Generalized Eigenvalue Problem with a nonsmooth Regularizer.

    PubMed

    Hwang, Seong Jae; Collins, Maxwell D; Ravi, Sathya N; Ithapu, Vamsi K; Adluru, Nagesh; Johnson, Sterling C; Singh, Vikas

    2015-12-01

    Eigenvalue problems are ubiquitous in computer vision, covering a very broad spectrum of applications ranging from estimation problems in multi-view geometry to image segmentation. Few other linear algebra problems have a more mature set of numerical routines available and many computer vision libraries leverage such tools extensively. However, the ability to call the underlying solver only as a "black box" can often become restrictive. Many 'human in the loop' settings in vision frequently exploit supervision from an expert, to the extent that the user can be considered a subroutine in the overall system. In other cases, there is additional domain knowledge, side or even partial information that one may want to incorporate within the formulation. In general, regularizing a (generalized) eigenvalue problem with such side information remains difficult. Motivated by these needs, this paper presents an optimization scheme to solve generalized eigenvalue problems (GEP) involving a (nonsmooth) regularizer. We start from an alternative formulation of GEP where the feasibility set of the model involves the Stiefel manifold. The core of this paper presents an end to end stochastic optimization scheme for the resultant problem. We show how this general algorithm enables improved statistical analysis of brain imaging data where the regularizer is derived from other 'views' of the disease pathology, involving clinical measurements and other image-derived representations.

  13. Improving insight and non-insight problem solving with brief interventions.

    PubMed

    Wen, Ming-Ching; Butler, Laurie T; Koutstaal, Wilma

    2013-02-01

    Developing brief training interventions that benefit different forms of problem solving is challenging. In earlier research, Chrysikou (2006) showed that engaging in a task requiring generation of alternative uses of common objects improved subsequent insight problem solving. These benefits were attributed to a form of implicit transfer of processing involving enhanced construction of impromptu, on-the-spot or 'ad hoc' goal-directed categorizations of the problem elements. Following this, it is predicted that the alternative uses exercise should benefit abilities that govern goal-directed behaviour, such as fluid intelligence and executive functions. Similarly, an indirect intervention - self-affirmation (SA) - that has been shown to enhance cognitive and executive performance after self-regulation challenge and when under stereotype threat, may also increase adaptive goal-directed thinking and likewise should bolster problem-solving performance. In Experiment 1, brief single-session interventions, involving either alternative uses generation or SA, significantly enhanced both subsequent insight and visual-spatial fluid reasoning problem solving. In Experiment 2, we replicated the finding of benefits of both alternative uses generation and SA on subsequent insight problem-solving performance, and demonstrated that the underlying mechanism likely involves improved executive functioning. Even brief cognitive- and social-psychological interventions may substantially bolster different types of problem solving and may exert largely similar facilitatory effects on goal-directed behaviours. © 2012 The British Psychological Society.

  14. Learning automata-based solutions to the nonlinear fractional knapsack problem with applications to optimal resource allocation.

    PubMed

    Granmo, Ole-Christoffer; Oommen, B John; Myrer, Svein Arild; Olsen, Morten Goodwin

    2007-02-01

    This paper considers the nonlinear fractional knapsack problem and demonstrates how its solution can be effectively applied to two resource allocation problems dealing with the World Wide Web. The novel solution involves a "team" of deterministic learning automata (LA). The first real-life problem relates to resource allocation in web monitoring so as to "optimize" information discovery when the polling capacity is constrained. The disadvantages of the currently reported solutions are explained in this paper. The second problem concerns allocating limited sampling resources in a "real-time" manner with the purpose of estimating multiple binomial proportions. This is the scenario encountered when the user has to evaluate multiple web sites by accessing a limited number of web pages, and the proportions of interest are the fraction of each web site that is successfully validated by an HTML validator. Using the general LA paradigm to tackle both of the real-life problems, the proposed scheme improves a current solution in an online manner through a series of informed guesses that move toward the optimal solution. At the heart of the scheme, a team of deterministic LA performs a controlled random walk on a discretized solution space. Comprehensive experimental results demonstrate that the discretization resolution determines the precision of the scheme, and that for a given precision, the current solution (to both problems) is consistently improved until a nearly optimal solution is found--even for switching environments. Thus, the scheme, while being novel to the entire field of LA, also efficiently handles a class of resource allocation problems previously not addressed in the literature.

  15. Serious physical fighting and gambling-related attitudes and behaviors in adolescents

    PubMed Central

    Slavin, Melissa; Pilver, Corey E.; Hoff, Rani A.; Krishnan-Sarin, Suchitra; Steinberg, Marvin A.; Rugle, Loreen; Potenza, Marc N.

    2013-01-01

    Background and aims: Physical fighting and gambling are common risk behaviors among adolescents. Prior studies have found associations among these behaviors in adolescents but have not examined systematically the health and gambling correlates of problem-gambling severity amongst youth stratified by fight involvement. Methods: Survey data were used from 2,276 Connecticut high school adolescents regarding their physical fight involvement, gambling behaviors and perceptions, and health and functioning. Gambling perceptions and correlates of problem-gambling severity were examined in fighting and non-fighting adolescents. Results: Gambling perceptions were more permissive and at-risk/problem gambling was more frequent amongst adolescents reporting serious fights versus those denying serious fights. A stronger relationship between problem-gambling severity and regular smoking was observed for adolescents involved in fights. Discussion and conclusions: The more permissive gambling attitudes and heavier gambling associated with serious fights in high school students suggest that youth who engage in physical fights warrant enhanced prevention efforts related to gambling. The stronger relationship between tobacco smoking and problem-gambling severity amongst youth engaging in serious fights suggest that fighting youth who smoke might warrant particular screening for gambling problems and subsequent interventions. PMID:24294502

  16. Students’ difficulties in probabilistic problem-solving

    NASA Astrophysics Data System (ADS)

    Arum, D. P.; Kusmayadi, T. A.; Pramudya, I.

    2018-03-01

    There are many errors can be identified when students solving mathematics problems, particularly in solving the probabilistic problem. This present study aims to investigate students’ difficulties in solving the probabilistic problem. It focuses on analyzing and describing students errors during solving the problem. This research used the qualitative method with case study strategy. The subjects in this research involve ten students of 9th grade that were selected by purposive sampling. Data in this research involve students’ probabilistic problem-solving result and recorded interview regarding students’ difficulties in solving the problem. Those data were analyzed descriptively using Miles and Huberman steps. The results show that students have difficulties in solving the probabilistic problem and can be divided into three categories. First difficulties relate to students’ difficulties in understanding the probabilistic problem. Second, students’ difficulties in choosing and using appropriate strategies for solving the problem. Third, students’ difficulties with the computational process in solving the problem. Based on the result seems that students still have difficulties in solving the probabilistic problem. It means that students have not able to use their knowledge and ability for responding probabilistic problem yet. Therefore, it is important for mathematics teachers to plan probabilistic learning which could optimize students probabilistic thinking ability.

  17. "What Brings Him Here Today?": Medical Problem Presentation Involving Children with Autism Spectrum Disorders and Typically Developing Children

    ERIC Educational Resources Information Center

    Solomon, Olga; Heritage, John; Yin, Larry; Maynard, Douglas W.; Bauman, Margaret L.

    2016-01-01

    Conversation and discourse analyses were used to examine medical problem presentation in pediatric care. Healthcare visits involving children with ASD and typically developing children were analyzed. We examined how children's communicative and epistemic capabilities, and their opportunities to be socialized into a competent patient role are…

  18. Problem-Based Learning Pedagogies: Psychological Processes and Enhancement of Intelligences

    ERIC Educational Resources Information Center

    Tan, Oon-Seng

    2007-01-01

    Education in this 21st century is concerned with developing intelligences. Problem solving in real-world contexts involves multiple ways of knowing and learning. Intelligence in the real world involves not only learning how to do things effectively but also more importantly the ability to deal with novelty and growing our capacity to adapt, select…

  19. Longitudinal Modeling of Adolescents' Activity Involvement, Problem Peer Associations, and Youth Smoking

    ERIC Educational Resources Information Center

    Metzger, Aaron; Dawes, Nickki; Mermelstein, Robin; Wakschlag, Lauren

    2011-01-01

    Longitudinal associations among different types of organized activity involvement, problem peer associations, and cigarette smoking were examined in a sample of 1040 adolescents (mean age = 15.62 at baseline, 16.89 at 15-month assessment, 17.59 at 24 months) enriched for smoking experimentation (83% had tried smoking). A structural equation model…

  20. Alcohol Highway-Traffic Safety Workshop for Alcohol Rehabilitation and Treatment Personnel.

    ERIC Educational Resources Information Center

    Walker, William; And Others

    The manual, designed for one-day workshops for 20 to 40 alcoholism rehabilitation and treatment professionals who are involved with traffic safety problems, is one of a series of five workshop manuals developed to assist State and local agencies involved in the development of programs for coping with the drinking-driver problem. Workshop goals…

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