Investigating middle school students’ difficulties in mathematical literacy problems level 1 and 2

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Setiawati, S.; Herman, T.; Jupri, A.

2017-11-01

The background of this study is the lack of mathematical literacy skills of students. The proficiency of students’ mathematical literacy skills based on the results of the PISA 2015 study shows that Indonesian students at the proficiency level 1. This fact gave rise to this study which aims to investigate middle school students’ difficulties in mathematical literacy problems level 1 and 2. Qualitative research was used in this study. An individual written test on mathematical literacy problems was administered, followed by interviews. The subjects of the study were 61 students grade VII in Bandung and 26 of them were interviewed afterward. Data analysis revealed that students’ error in performing arithmetic most frequently observed. Other observed difficulties concerned understanding about algebra concept, applying arithmetic operation in algebraic expressions, and interpreting symbols to represent the unknown. In solving mathematical literacy problems, students use their prior knowledge, although sometimes not relevant to the questions. Based on the results, we suggest that mathematics learning in contextual learning and which invites students to participate in the processes of understanding the concepts.

The Prevalence of Reading Difficulties among Children in Scholar Age

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Maria Rosita Cecilia

2014-10-01

Full Text Available The study investigates the prevalence of reading difficulties among children in scholar age and analyses the socio-demographic characteristics of learners who presented reading difficulties in central Italy. A sample of 623 students 7-11 aged, was assessed with the Italian MT standardized tests. Information on gender, age, handedness, and other socio-demographic variables were also gathered. The study showed that 11% of learners presented poor comprehension skills. The reading speed difficulties were more common than the reading correctness problems: about 7% of children vs 1% were dyslexics due to slow reading. There were no significant differences regarding gender, age. However, dominant hand and the school location seemed to affect the speed difficulties and the comprehension problems. The analyses showed that attending a school located in a rural area was statistically associated with the reading difficulties. Left-handed children were more likely to be slow decoders and/or poor comprehenders. These findings may be used in the early diagnosis of poor readers. These difficulties often have a chronic progression with substantial psychosocial limitations and psychological stress, so children with reading difficulties should be identified as early as possible.

Sensory Processing Difficulties in Toddlers With Nonorganic Failure-to-Thrive and Feeding Problems.

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Yi, Sook-Hee; Joung, Yoo-Sook; Choe, Yon Ho; Kim, Eun-Hye; Kwon, Jeong-Yi

2015-06-01

Failure-to-thrive is defined as an abnormally low weight and/or height for age. The term "nonorganic failure-to-thrive" (NOFT) has been used to describe "failure-to-thrive" without an obvious cause underlying the growth failure. The purpose of the present study was to compare sensory processing abilities between toddlers with NOFT and feeding problems and age-matched controls. Toddlers with NOFT and feeding problems (N = 16) were recruited from the pediatric feeding clinic in a tertiary university hospital, and age-matched controls (N = 16) were recruited from community volunteers. They were evaluated for sensory processing ability using an Infant/Toddler Sensory Profile (ITSP), and for development of cognition, motor skills, and language using the Bayley Scales of Infant Development II and Sequenced Language Scale for Infants. Behavior at mealtime was evaluated using the Behavioral Pediatrics Feeding Assessment Scale. In the NOFT with feeding problems group, atypical performances were more frequently observed in 3 of 5 ITSP section items (tactile, vestibular, and oral) compared with those in the control group. Significant delayed development of cognition, motor skills, and language was observed in the NOFT with feeding problems group compared with that in the control group. In addition, children who showed 1 or more atypical performances in ITSP had delayed development in cognition, motor skills, and language. Sensory processing problems were more commonly observed in toddlers with feeding problems and growth deficiency. The present study could provide a preliminary evidence for a possible impact of the sensory processing problems on the feeding difficulties in toddlers with NOFT. Future large studies should be conducted to clarify the relation between sensory processing difficulties and feeding problems in toddlers.

Motor performance and learning difficulties in schoolchildren aged 7 to 10 years old

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J. Silva

2011-01-01

Full Text Available The general objective of this study was to evaluate the motor performance of children with and without learning difficulty indicatives. Took part in the study 406 students aged 7 to 10 years old, being 231 girls (56.9% and 175 (43.1% boys enrolled in a municipal public school in São José, Santa Catarina, Brazil. The indicative of learning difficulties was verified through the TDE, while motor performance was evaluated with the MABC. Boys without learning difficulties had better performance in the majority of the abilities evaluated, beyond an association between the indicative of motor problems with learning difficulties towards writing, arithmetic, reading, and in general. On the other hand, female students of the sample with and without any indicative of learning difficulties did not differentiate themselves as to motor abilities evaluated, with an association merely between the indicative of motor problems and reading problems. Based on the differences identified between girls and boys, results call attention to the need for future research in this area, considering gender as a differential variable in this relationship.

Student difficulties with Gauss' law

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Kanim, Stephen

2000-09-01

Many students in introductory courses have difficulty solving Gauss' law problems. Through interviews with students and analysis of solutions to homework and examination questions we have identified some specific conceptual difficulties that often contribute to students' inability to solve quantitative Gauss' law problems. We give examples of common difficulties and discuss instructional implications.

The Use of a Bar Model Drawing to Teach Word Problem Solving to Students with Mathematics Difficulties

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Morin, Lisa L.; Watson, Silvana M. R.; Hester, Peggy; Raver, Sharon

2017-01-01

For students with mathematics difficulties (MD), math word problem solving is especially challenging. The purpose of this study was to examine the effects of a problem-solving strategy, bar model drawing, on the mathematical problem-solving skills of students with MD. The study extended previous research that suggested that schematic-based…

An Investigation into Students' Difficulties in Numerical Problem Solving Questions in High School Biology Using a Numeracy Framework

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Scott, Fraser J.

2016-01-01

The "mathematics problem" is a well-known source of difficulty for students attempting numerical problem solving questions in the context of science education. This paper illuminates this problem from a biology education perspective by invoking Hogan's numeracy framework. In doing so, this study has revealed that the contextualisation of…

A Case Study: The Implementation of a Problem-Solving Model with a Student with Reading Difficulties in Turkey

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Ozmen, E. Ruya; Doganay-Bilgi, Arzu

2016-01-01

The purpose of this case study was to improve the reading accuracy and reading comprehension of a 10-year-old fourth-grade female student with reading difficulties. For that purpose, the problem- solving model was implemented in four stages. These stages included problem identification, problem analysis, intervention, and evaluation. During the…

The Affective Dimensions of Mathematical Difficulties in Schoolchildren

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Morena Lebens

2011-01-01

Full Text Available Mathematical difficulties (MDs are frequently characterised by cognitive deficits such as ineffective problem solving strategies and a lack of computational fluency. The established literature indicates that mathematical achievement is not only a function of cognitive factors but it also points to the importance of affective factors for the development of mathematical achievement. In the light of this evidence, the exploration of children's affective responses towards mathematics becomes a central issue. Whereas previous studies tended to research affective motivational constructs such as self-efficacy in isolation from other related constructs, the literature suffers from a shortage of research on the relationship between different affective motivational variables and their impact on mathematical achievement in different age and achievement bands. The present paper aims to address this aim by employing a newly developed instrument to measure affective motivational variables. Overall, the present findings support the assumption that children of average ability are less influenced by affective factors than children with mathematical difficulties.

Towards a conceptual framework for identifying student difficulties with solving Real-World Problems in Physics

DEFF Research Database (Denmark)

Niss, Martin

2012-01-01

This paper develops a conceptual framework for identifying the challenges and obstacles university students encounter when solving real-world problems involving Physics. The framework is based on viewing problem solving as a modelling process. In order to solve a real-world problem, the problem...... solver has to go through the steps and do the tasks of such a process. The paper presents a theoretical analysis of what it takes to solve three real-world problems, demonstrating how the framework presented captures the essential aspects of solving them. Moreover, it is argued that three steps critical...... for real-world problem solving – initial analysis of the problem situation, choice of relevant physical theory (the so-called paradigmatic choice) and mathematization – are not covered by existing models of problem solving in Physics. Finally, the existing research on student difficulties with problem...

Researching consumers' attitudes: Some difficulties, problems and dilemmas

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Gutić Dragutin

2010-01-01

Full Text Available Consumers' attitudes have always had a central place in marketing theory and practice. There is a great number of different problems, difficulties and dilemmas, which come from different sources and have different content, and which very often arise as a stumbling block in researching consumers' attitudes. Part of them is already contained in different views on term attitudes itself. The second part lies in an unsolved puzzle of consumers' attitudes and behaviour relation. The third part is of methodological nature in research. The fourth is in usage of different, numerous techniques that researchers have at their disposal when researching attitudes. It might sound unbelievable, but since the 1960s till today, very few researchers have understood, and knew real nature of the term, essence and meaning of attitudes in marketing. There is even less of them who know how to examine attitudes and generally use adequately and productively. Attitudes belong to the most complex psychical processes. The complexity of attitudes is manifesting during the research. It is not a rarity to become convinced that important contents, such as: determining dimensions, components, sources of emerging and stability of researched attitudes are not present in attitudes' examination and research. In most cases, research results of consumers' attitudes are actually nothing more than statements about the existence of positive and negative attitudes. There is still no complex method that can be used in research. Different, essentially partial methods are being used instead, usually to investigate particular components and dimensions of consumers' attitudes. There are more groups of problems that appear in consumers' attitudes examination. For this occasion, we point out three: problems that result from lack of knowledge and not adequate understanding of attitudes; problems related to level of examinee's (consumer's consciousness of his attitude; problems emerging from

Psychometric Properties of the Strengths and Difficulties Questionnaire and Mental Health Problems among Children with Hearing Loss

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Niclasen, Janni; Dammeyer, Jesper

2016-01-01

More knowledge is needed about the characteristics of mental health problems among deaf or hard of hearing (D/HH) children. This study investigates the factor structure of one of the most widely used screening tools, the Strengths and Difficulties Questionnaire (SDQ), and the prevalence of mental health problems among D/HH children. Our data were…

Improvement of Word Problem Solving and Basic Mathematics Competencies in Students with Attention Deficit/Hyperactivity Disorder and Mathematical Learning Difficulties

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González-Castro, Paloma; Cueli, Marisol; Areces, Débora; Rodríguez, Celestino; Sideridis, Georgios

2016-01-01

Problem solving represents a salient deficit in students with mathematical learning difficulties (MLD) primarily caused by difficulties with informal and formal mathematical competencies. This study proposes a computerized intervention tool, the integrated dynamic representation (IDR), for enhancing the early learning of basic mathematical…

Investigating the Difficulties and Problems Faced by the English Language Students of Al Quds Open University in Legal Translation Process

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Ahmed Maher Mahmoud Al-Nakhalah

2013-12-01

Full Text Available Following experimental descriptive method, the paper explores the difficulties and problems faced by the English language students of Al Quds Open University in legal translation process; that is, while translating legal terms/documents from Arabic to English and from English to Arabic. A test was designed by the researcher in order to explore and investigate the difficulties and problems faced by the students. The test included four questions: 1 Translating English legal paragraph, 2 Translating Arabic legal paragraph, 3 Translating ten Arabic legal terms and 4 Translating ten English legal terms. The test was applied on the English language students of Al Quds Open University in Gaza Region in Palestine during the second course of the academic year 2010/2011. The samples of the study were chosen and selected randomly. Following suitable statistical methods, the paper offers the obtained results with critical discussion. Possible solutions, recommendations and suggestions to overcome these difficulties and problems also form important parts of the discussion in the paper.

Analysis of difficulties in mathematics problem solving based on revised Bloom’s Taxonomy viewed from high self-efficacy

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Prismana, R. D. E.; Kusmayadi, T. A.; Pramudya, I.

2018-04-01

The ability of solving problem is a part of the mathematic curriculum that is very important. Problem solving prefers the process and strategy that is done by students in solving a problem rather than the result. This learning concept in accordance with the stages on the revised bloom’s taxonomy. The revised Bloom’s Taxonomy has two dimensions, namely the dimension of cognitive process and the dimension of knowledge. Dimension of knowledge has four categories, but this study only restricted on two knowledge, conceptual knowledge and procedural knowledge. Dimensions of cognitive processes are categorized into six kinds, namely remembering, understanding, applying, analyzing, evaluating, and creating. Implementation of learning more emphasis on the role of students. Students must have their own belief in completing tasks called self-efficacy. This research is a qualitative research. This research aims to know the site of the students’ difficulty based on revised Bloom’s Taxonomy viewed from high self-efficacy. The results of the study stated the students with high self efficacy have difficulties site. They are evaluating conceptual knowledge, evaluating procedural knowledge, creating conceptual knowledge, and creating procedural knowledge. It could be the consideration of teachers in the teaching, so as to reduce the difficulties of learning in students.

The association of ADHD and depression: Mediation by peer problems and parent-child difficulties in two complementary samples

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Humphreys, Kathryn L.; Katz, Shaina J.; Lee, Steve S.; Hammen, Constance L.; Brennan, Patricia A.; Najman, Jake M.

2013-01-01

Children with attention-deficit/hyperactivity disorder (ADHD) are at increased risk for the development of depression, with evidence that peer and academic difficulties mediate predictions of later depression from ADHD. The present study hypothesized that parent-child relationship difficulties may be an additional potential mediator of this association. Academic, peer, and parent-child functioning were tested as mediators of the association of attention problems and depression in two distinctly different, yet complementary samples. Study 1 was a cross-sectional sample of 230 5–10 year-old children with and without ADHD. Study 2 was a prospective longitudinal sample of 472 youth followed prospectively from birth to age 20 at risk for depression. Despite differences in age, measures, and designs, both studies implicated peer and parent-child problems as unique mediators of depressive symptoms, although academic difficulties did not uniquely mediate the ADHD-depression association. Further, inattention symptoms, but not hyperactivity, predicted depressive symptoms via the disruption of interpersonal functioning. The inclusion of oppositional defiant disorder into models impacted results, and supported its independent role in parent-child problems. Implications include support for interventions that target interpersonal competence, which may effectively reduce the risk of depression among children with ADHD. PMID:24016021

Heterogeneity of emotional and interpersonal difficulties in alcohol-dependence: A cluster analytic approach.

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Maurage, Pierre; Timary, Philippe de; D'Hondt, Fabien

2017-08-01

Emotional and interpersonal impairments have been largely reported in alcohol-dependence, and their role in its development and maintenance is widely established. However, earlier studies have exclusively focused on group comparisons between healthy controls and alcohol-dependent individuals, considering them as a homogeneous population. The variability of socio-emotional profiles in this disorder thus remains totally unexplored. The present study used a cluster analytic approach to explore the heterogeneity of affective and social disorders in alcohol-dependent individuals. 296 recently-detoxified alcohol-dependent patients were first compared with 246 matched healthy controls regarding self-reported emotional (i.e. alexithymia) and social (i.e. interpersonal problems) difficulties. Then, a cluster analysis was performed, focusing on the alcohol-dependent sample, to explore the presence of differential patterns of socio-emotional deficits and their links with demographic, psychopathological and alcohol-related variables. The group comparison between alcohol-dependent individuals and controls clearly confirmed that emotional and interpersonal difficulties constitute a key factor in alcohol-dependence. However, the cluster analysis identified five subgroups of alcohol-dependent individuals, presenting distinct combinations of alexithymia and interpersonal problems ranging from a total absence of reported impairment to generalized socio-emotional difficulties. Alcohol-dependent individuals should no more be considered as constituting a unitary group regarding their affective and interpersonal difficulties, but rather as a population encompassing a wide variety of socio-emotional profiles. Future experimental studies on emotional and social variables should thus go beyond mere group comparisons to explore this heterogeneity, and prevention programs proposing an individualized evaluation and rehabilitation of these deficits should be promoted. Copyright © 2017

Precursors of Reading Difficulties in Czech and Slovak Children At-Risk of Dyslexia.

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Moll, Kristina; Thompson, Paul A; Mikulajova, Marina; Jagercikova, Zuzana; Kucharska, Anna; Franke, Helena; Hulme, Charles; Snowling, Margaret J

2016-05-01

Children with preschool language difficulties are at high risk of literacy problems; however, the nature of the relationship between delayed language development and dyslexia is not understood. Three hundred eight Slovak and Czech children were recruited into three groups: family risk of dyslexia, speech/language difficulties and controls, and were assessed three times from kindergarten until Grade 1. There was a twofold increase in probability of reading problems in each risk group. Precursors of 'dyslexia' included difficulties in oral language and code-related skills (phoneme awareness, letter-knowledge and rapid automatized naming); poor performance in phonological memory and vocabulary was observed in both affected and unaffected high-risk peers. A two-group latent variable path model shows that early language skills predict code-related skills, which in turn predict literacy skills. Findings suggest that dyslexia in Slavic languages has its origins in early language deficits, and children who succumb to reading problems show impaired code-related skills before the onset of formal reading instruction. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

New Model of Mapping Difficulties in Solving Analogical Problems among Adolescents and Adults with Intellectual Disability

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Lifshitz, Hefziba; Weiss, Itzhak; Tzuriel, David; Tzemach, Moran

2011-01-01

The main goal of the study was to map the difficulties and cognitive processes among adolescents (aged 13-21, N = 30) and adults (aged 25-66, N = 30) with mild and moderate intellectual disability (ID) when solving analogical problems. The participants were administered the "Conceptual and Perceptual Analogical Modifiability" test. A…

Brain potentials during mental arithmetic: effects of extensive practice and problem difficulty.

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Pauli, P; Lutzenberger, W; Rau, H; Birbaumer, N; Rickard, T C; Yaroush, R A; Bourne, L E

1994-07-01

Recent behavioral investigations indicate that the processes underlying mental arithmetic change systematically with practice from deliberate, conscious calculation to automatic, direct retrieval of answers from memory [Bourne, L.E.Jr. and Rickard, T.C., Mental calculation: The development of a cognitive skill, Paper presented at the Interamerican Congress of Psychology, San Jose, Costa Rica, 1991: Psychol. Rev., 95 (1988) 492-527]. Results reviewed by Moscovitch and Winocur [In: The handbook of aging and cognition, Erlbaum, Hillsdale, NJ, 1992, pp. 315-372] suggest that consciously controlled processes are more dependent on frontal lobe function than are automatic processes. It is appropriate, therefore to determine whether transitions in the locus of primary brain activity occur with practice on mental calculation. In this experiment, we examine the relationship between characteristics of event-related brain potentials (ERPs) and mental arithmetic. Single-digit mental multiplication problems varying in difficulty (problem size) were used, and subjects were trained on these problems for four sessions. Problem-size and practice effects were reliably found in behavioral measures (RT). The ERP was characterized by a pronounced late positivity after task presentation followed by a slow wave, and a negativity during response indication. These components responded differentially to the practice and problem-size manipulations. Practice mainly affected topography of the amplitude of positivity and offset latency of slow wave, and problem-size mainly offset latency of slow wave and pre-response negativity. Fronto-central positivity diminished from session to session, and the focus of positivity centered finally at centro-parietal regions.(ABSTRACT TRUNCATED AT 250 WORDS)

Boundary value problems and partial differential equations

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Powers, David L

2005-01-01

Boundary Value Problems is the leading text on boundary value problems and Fourier series. The author, David Powers, (Clarkson) has written a thorough, theoretical overview of solving boundary value problems involving partial differential equations by the methods of separation of variables. Professors and students agree that the author is a master at creating linear problems that adroitly illustrate the techniques of separation of variables used to solve science and engineering.* CD with animations and graphics of solutions, additional exercises and chapter review questions* Nearly 900 exercises ranging in difficulty* Many fully worked examples

Alexithymia and psychosocial problems among Italian preadolescents. A latent class analysis approach.

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Mannarini, Stefania; Balottin, Laura; Toldo, Irene; Gatta, Michela

2016-10-01

The study, conducted on Italian preadolscents aged 11 to 13 belonging to the general population, aims to investigate the relationship between the emotional functioning, namely, alexithymia, and the risk of developing behavioral and emotional problems measured using the Strength and Difficulty Questionnaire. The latent class analysis approach allowed to identify two latent variables, accounting for the internalizing (emotional symptoms and difficulties in emotional awareness) and for the externalizing problems (conduct problems and hyperactivity, problematic relationships with peers, poor prosocial behaviors and externally oriented thinking). The two latent variables featured two latent classes: the difficulty in dealing with problems and the strength to face problems that was representative of most of the healthy participants with specific gender differences. Along with the analysis of psychopathological behaviors, the study of resilience and strengths can prove to be a key step in order to develop valuable preventive approaches to tackle psychiatric disorders. © 2016 Scandinavian Psychological Associations and John Wiley & Sons Ltd.

Childhood maltreatment, intervening variables, and adult psychological difficulties in women: an overview.

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Briere, John; Jordan, Carol E

2009-10-01

This article reviews the complex relationship between child maltreatment and later psychosocial difficulties among adult women. Specifically addressed are (a) the various forms of childhood maltreatment, (b) the range of potential long-term psychological outcomes, and (c) important contextual variables that mediate or add to these maltreatment-symptom relationships. Among the latter are characteristics of the abuse and/or neglect; effects of impaired parental functioning; premaltreatment and postmaltreatment psychobiology; qualities of the parent-child attachment; abuse and/or neglect-related affect dysregulation that may lead to further symptomatology; the extent to which the child responds with significant emotional or behavioral avoidance; and whether later traumas are also present. Also relevant are sociocultural contributors to both child maltreatment and maltreatment effects, especially poverty and marginalization. Clinical and research implications are considered.

Difficulties in Genetics Problem Solving.

Science.gov (United States)

Tolman, Richard R.

1982-01-01

Examined problem-solving strategies of 30 high school students as they solved genetics problems. Proposes a new sequence of teaching genetics based on results: meiosis, sex chromosomes, sex determination, sex-linked traits, monohybrid and dihybrid crosses (humans), codominance (humans), and Mendel's pea experiments. (JN)

Mental health problems in pre-school children with specific language impairment: Use of the Strengths and Difficulties Questionnaire

NARCIS (Netherlands)

Flapper, B.C.; Bos, A.C.; Jansen, D.E.

2011-01-01

The prevalence of mental health problems (MHP) in children with language disorders ranges from 11 to 55%, due to additional disabilities that have a significant relationship to psychosocial difficulties. Specialists assume that children with a selective disorder [selective language impairment

New complex variable meshless method for advection—diffusion problems

International Nuclear Information System (INIS)

Wang Jian-Fei; Cheng Yu-Min

2013-01-01

In this paper, an improved complex variable meshless method (ICVMM) for two-dimensional advection—diffusion problems is developed based on improved complex variable moving least-square (ICVMLS) approximation. The equivalent functional of two-dimensional advection—diffusion problems is formed, the variation method is used to obtain the equation system, and the penalty method is employed to impose the essential boundary conditions. The difference method for two-point boundary value problems is used to obtain the discrete equations. Then the corresponding formulas of the ICVMM for advection—diffusion problems are presented. Two numerical examples with different node distributions are used to validate and inestigate the accuracy and efficiency of the new method in this paper. It is shown that ICVMM is very effective for advection—diffusion problems, and has a good convergent character, accuracy, and computational efficiency

Self reported behavioral and emotional difficulties in relation to dentition status among school going children of Dilsukhnagar, Hyderabad, India.

Science.gov (United States)

Srilatha, Adepu; Doshi, Dolar; Reddy, Madupu Padma; Kulkarni, Suhas; Reddy, Bandari Srikanth

2016-01-01

Oral health has strong biological, psychological, and social projections, which influence the quality of life. Thus, developing a common vision and a comprehensive approach to address children's social, emotional, and behavioral health needs is an integral part of the child and adolescent's overall health. To assess and compare the behavior and emotional difficulties among 15-year-olds and to correlate it with their dentition status based on gender. Study Settings and Design: A cross-sectional questionnaire study among 15-year-old schoolgoing children in six private schools in Dilsukhnagar, Hyderabad, India. The behavior and emotional difficulties were assessed using self-reported Strengths and Difficulties Questionnaire (SDQ). The dentition status was recorded by the criteria given by the World Health Organization (WHO) in the Basic Oral Health Survey Assessment Form (1997). Independent Student's t-test was used for comparison among the variables. Correlation between scales of SDQ and dentition status was done using Karl Pearson's correlation coefficient method. Girls reported more emotional problems and good prosocial behavior and males had more conduct problems, hyperactivity, peer problems, and total difficulty problems. Total decayed-missing-filled teeth (DMFT) and decayed component were significantly and positively correlated with total difficulty, emotional symptom, and conduct problems scale while missing component was correlated with the hyperactivity scale and filled component with prosocial behavior. DMFT and its components showed an association with all scales of SDQ except for peer problem scale. Thus, the oral health of children was significantly influenced by behavioral and emotional difficulties; so, changes in the mental health status will affect the oral health of children.

Does Cognitive Strategy Training on Word Problems Compensate for Working Memory Capacity in Children with Math Difficulties?

Science.gov (United States)

Swanson, H. Lee

2014-01-01

Cognitive strategies are important tools for children with math difficulties (MD) in learning to solve word problems. The effectiveness of strategy training, however, depends on working memory capacity (WMC). Thus, children with MD but with relatively higher WMC are more likely to benefit from strategy training, whereas children with lower WMC may…

Contribution of Equal-Sign Instruction beyond Word-Problem Tutoring for Third-Grade Students with Mathematics Difficulty.

Science.gov (United States)

Powell, Sarah R; Fuchs, Lynn S

2010-05-01

Elementary school students often misinterpret the equal sign (=) as an operational rather than a relational symbol. Such misunderstanding is problematic because solving equations with missing numbers may be important for higher-order mathematics skills including word problems. Research indicates equal-sign instruction can alter how typically-developing students use the equal sign, but no study has examined effects for students with mathematics difficulty (MD) or how equal-sign instruction contributes to word-problem skill for students with or without MD. The present study assessed the efficacy of equal-sign instruction within word-problem tutoring. Third-grade students with MD (n = 80) were assigned to word-problem tutoring, word-problem tutoring plus equal-sign instruction (combined) tutoring, or no-tutoring control. Combined tutoring produced better improvement on equal sign tasks and open equations compared to the other 2 conditions. On certain forms of word problems, combined tutoring but not word-problem tutoring alone produced better improvement than control. When compared at posttest to 3(rd)-grade students without MD on equal sign tasks and open equations, only combined tutoring students with MD performed comparably.

Difficulties of Secondary school teachers implicating in the reading, innovation and research in science education (II: the problem of “hands-on”

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Oliva Martínez, José María

2012-04-01

Full Text Available This work is a continuation of another recent article in these pages (Oliva, 2011, which dealt with the difficulties of high school teachers to start in the dynamics of innovation and research in science education. In another study that examined the views expressed by a sample of 16 secondary science teachers around the obstacles to immersion in these tasks, as well as comments, expressed doubts and obstacles they face the task write a short article in the context of an introductory training course on this subject. From the same source, in this other paper the intrinsic difficulties that arise once the teachers decide to engage in this type of work and faces the tasks associated with these processes. The problems identified in this case are due, among other reasons, lack of trust in teachers' own possibilities, difficulties in the formulating of the problem object of research, lack of theoretical and problems in drafting written work. From the above results makes some conclusions and implications for teacher training in this field.

Tinnitus and Sleep Difficulties After Cochlear Implantation.

Science.gov (United States)

Pierzycki, Robert H; Edmondson-Jones, Mark; Dawes, Piers; Munro, Kevin J; Moore, David R; Kitterick, Pádraig T

To estimate and compare the prevalence of and associations between tinnitus and sleep difficulties in a sample of UK adult cochlear implant users and those identified as potential candidates for cochlear implantation. The study was conducted using the UK Biobank resource, a population-based cohort of 40- to 69-year olds. Self-report data on hearing, tinnitus, sleep difficulties, and demographic variables were collected from cochlear implant users (n = 194) and individuals identified as potential candidates for cochlear implantation (n = 211). These "candidates" were selected based on (i) impaired hearing sensitivity, inferred from self-reported hearing aid use and (ii) impaired hearing function, inferred from an inability to report words accurately at negative signal to noise ratios on an unaided closed-set test of speech perception. Data on tinnitus (presence, persistence, and related distress) and on sleep difficulties were analyzed using logistic regression models controlling for gender, age, deprivation, and neuroticism. The prevalence of tinnitus was similar among implant users (50%) and candidates (52%; p = 0.39). However, implant users were less likely to report that their tinnitus was distressing at its worst (41%) compared with candidates (63%; p = 0.02). The logistic regression model suggested that this difference between the two groups could be explained by the fact that tinnitus was less persistent in implant users (46%) compared with candidates (72%; p reported difficulties with sleep were similar among implant users (75%) and candidates (82%; p = 0.28), but participants with tinnitus were more likely to report sleep difficulties than those without (p explanation is supported by the similar prevalence of sleep problems among implant users and potential candidates for cochlear implantation, despite differences between the groups in tinnitus persistence and related emotional distress. Cochlear implantation may therefore not be an appropriate intervention

Self reported behavioral and emotional difficulties in relation to dentition status among school going children of Dilsukhnagar, Hyderabad, India

Directory of Open Access Journals (Sweden)

Adepu Srilatha

2016-01-01

Full Text Available Background: Oral health has strong biological, psychological, and social projections, which influence the quality of life. Thus, developing a common vision and a comprehensive approach to address children′s social, emotional, and behavioral health needs is an integral part of the child and adolescent′s overall health. Aim: To assess and compare the behavior and emotional difficulties among 15-year-olds and to correlate it with their dentition status based on gender. Study Settings and Design: A cross-sectional questionnaire study among 15-year-old schoolgoing children in six private schools in Dilsukhnagar, Hyderabad, India. Materials and Methods: The behavior and emotional difficulties were assessed using self-reported Strengths and Difficulties Questionnaire (SDQ. The dentition status was recorded by the criteria given by the World Health Organization (WHO in the Basic Oral Health Survey Assessment Form (1997. Statistical Analysis: Independent Student′s t-test was used for comparison among the variables. Correlation between scales of SDQ and dentition status was done using Karl Pearson′s correlation coefficient method. Results: Girls reported more emotional problems and good prosocial behavior and males had more conduct problems, hyperactivity, peer problems, and total difficulty problems. Total decayed-missing-filled teeth (DMFT and decayed component were significantly and positively correlated with total difficulty, emotional symptom, and conduct problems scale while missing component was correlated with the hyperactivity scale and filled component with prosocial behavior. Conclusion: DMFT and its components showed an association with all scales of SDQ except for peer problem scale. Thus, the oral health of children was significantly influenced by behavioral and emotional difficulties; so, changes in the mental health status will affect the oral health of children.

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Bagagiolo, Fabio, E-mail: bagagiol@science.unitn.it; Benetton, Michela [Unversita di Trento, Dipartimento di Matematica (Italy)

2012-02-15

In this paper we are concerned with the optimal control problem consisting in minimizing the time for reaching (visiting) a fixed number of target sets, in particular more than one target. Such a problem is of course reminiscent of the famous 'Traveling Salesman Problem' and brings all its computational difficulties. Our aim is to apply the dynamic programming technique in order to characterize the value function of the problem as the unique viscosity solution of a suitable Hamilton-Jacobi equation. We introduce some 'external' variables, one per target, which keep in memory whether the corresponding target is already visited or not, and we transform the visiting problem in a suitable Mayer problem. This fact allows us to overcome the lacking of the Dynamic Programming Principle for the originary problem. The external variables evolve with a hysteresis law and the Hamilton-Jacobi equation turns out to be discontinuous.

Mood Instability Is a Precursor of Relationship and Marital Difficulties: Results from Prospective Data from the British Health and Lifestyle Surveys

Directory of Open Access Journals (Sweden)

Rudy Cecil Bowen

2017-12-01

Full Text Available The DSM system implies that affective instability is caused by reactivity to interpersonal events. We used the British Health and Lifestyle Survey that surveyed community residents in 1984 and again in 1991 to study competing hypotheses: that mood instability (MI leads to interpersonal difficulties or vice versa. We analyzed data from 5,352 persons who participated in both waves of the survey. Factor analysis of the Eysenck Personality Inventory neuroticism scale was used to derive a 4-item scale for MI. We used depression measures that were previously derived by factor analyzing the General Health Questionnaire. We tested the competing hypotheses by regressing variables at follow-up against baseline variables. The results showed that MI in 1984 clearly predicted the development of interpersonal problems in 1991. After adjusting for depression, depression becomes the main predictor of spousal difficulties, but MI remains a predictor of interpersonal difficulties with family and friends. Attempts to investigate the reverse hypothesis were ambiguous. The clinical implication is that when MI and interpersonal problems are reported, the MI should be treated first, or at least concurrently.

Model reduction method using variable-separation for stochastic saddle point problems

Science.gov (United States)

Jiang, Lijian; Li, Qiuqi

2018-02-01

In this paper, we consider a variable-separation (VS) method to solve the stochastic saddle point (SSP) problems. The VS method is applied to obtain the solution in tensor product structure for stochastic partial differential equations (SPDEs) in a mixed formulation. The aim of such a technique is to construct a reduced basis approximation of the solution of the SSP problems. The VS method attempts to get a low rank separated representation of the solution for SSP in a systematic enrichment manner. No iteration is performed at each enrichment step. In order to satisfy the inf-sup condition in the mixed formulation, we enrich the separated terms for the primal system variable at each enrichment step. For the SSP problems by regularization or penalty, we propose a more efficient variable-separation (VS) method, i.e., the variable-separation by penalty method. This can avoid further enrichment of the separated terms in the original mixed formulation. The computation of the variable-separation method decomposes into offline phase and online phase. Sparse low rank tensor approximation method is used to significantly improve the online computation efficiency when the number of separated terms is large. For the applications of SSP problems, we present three numerical examples to illustrate the performance of the proposed methods.

Simulating variable source problems via post processing of individual particle tallies

International Nuclear Information System (INIS)

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

2000-01-01

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 for 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

Are middle school mathematics teachers able to solve word problems without using variable?

Science.gov (United States)

Gökkurt Özdemir, Burçin; Erdem, Emrullah; Örnek, Tuğba; Soylu, Yasin

2018-01-01

Many people consider problem solving as a complex process in which variables such as x, y are used. Problems may not be solved by only using 'variable.' Problem solving can be rationalized and made easier using practical strategies. When especially the development of children at younger ages is considered, it is obvious that mathematics teachers should solve problems through concrete processes. In this context, middle school mathematics teachers' skills to solve word problems without using variables were examined in the current study. Through the case study method, this study was conducted with 60 middle school mathematics teachers who have different professional experiences in five provinces in Turkey. A test consisting of five open-ended word problems was used as the data collection tool. The content analysis technique was used to analyze the data. As a result of the analysis, it was seen that the most of the teachers used trial-and-error strategy or area model as the solution strategy. On the other hand, the teachers who solved the problems using variables such as x, a, n or symbols such as Δ, □, ○, * and who also felt into error by considering these solutions as without variable were also seen in the study.

PISA 2012 Analysis of School Variables Affecting Problem-Solving Competency: Turkey-Serbia Comparison

Directory of Open Access Journals (Sweden)

Emine YAVUZ

2017-12-01

Full Text Available According to the OECD's PISA 2012 Turkey problem-solving report, Turkey and Serbia are at the same mathematical literacy level. However, Serbia's average of problem-solving competency is said to be higher than Turkey's. In this study, school variables that affect problem-solving competency of the two countries were examined and compared. The method of the study was causal comparison method, and HLM analysis was performed on data of 4494 students from 147 schools in Turkey sample and 4059 students from 132 schools in Serbia sample separately. As a result of HLM analysis, "obstacle and family donation" variable for Serbia and "abandon, teacher morale and mathematics competition" variable for Turkey were statistically significant. Although it was found that for each countries different variables influence the problem-solving competency, it was quite remarkable that these variables are in common in that they are components of the school climate concept.

Are Middle School Mathematics Teachers Able to Solve Word Problems without Using Variable?

Science.gov (United States)

Gökkurt Özdemir, Burçin; Erdem, Emrullah; Örnek, Tugba; Soylu, Yasin

2018-01-01

Many people consider problem solving as a complex process in which variables such as "x," "y" are used. Problems may not be solved by only using "variable." Problem solving can be rationalized and made easier using practical strategies. When especially the development of children at younger ages is considered, it is…

Associations between Prenatal and Early Childhood Fish and Processed Food Intake, Conduct Problems, and Co-Occurring Difficulties.

Science.gov (United States)

Mesirow, Maurissa Sc; Cecil, Charlotte; Maughan, Barbara; Barker, Edward D

2017-07-01

Little is known about early life diet as a risk factor for early-onset persistent conduct problems (EOP CP). To investigate this, we used data from the Avon Longitudinal Study of Parents and Children, a UK-based prospective epidemiological birth cohort. 5727 mother-child pairs (49.9 % boys) monitored since pregnancy (delivery date between 1 April, 1991 and 31 December, 1992) reported intake of fish and processed foods at 32 weeks gestation and, for the child, at 3 years; EOP (n = 666) and Low conduct problem (Low CP, n = 5061) trajectories were measured from 4 to 13 years; hyperactivity and emotional difficulties were assessed in childhood (4-10 years) and early adolescence (12-13 years), in addition to potential confounding factors (family adversity, birth complications, income). Compared to Low CP, mothers of EOP children consumed less fish (p processed food (p processed food at 3 years (p processed food (vs. less than one serving/day, p processed food, and low in fish, associate with an EOP CP trajectory and co-occurring difficulties in early adolescence. As small effect size differences were found, further studies are needed to investigate the long-term impact of early unhealthy diet.

An efficient scheme for a phase field model for the moving contact line problem with variable density and viscosity

KAUST Repository

Gao, Min

2014-09-01

In this paper, we develop an efficient numerical method for the two phase moving contact line problem with variable density, viscosity, and slip length. The physical model is based on a phase field approach, which consists of a coupled system of the Cahn-Hilliard and Navier-Stokes equations with the generalized Navier boundary condition [1,2,5]. To overcome the difficulties due to large density and viscosity ratio, the Navier-Stokes equations are solved by a splitting method based on a pressure Poisson equation [11], while the Cahn-Hilliard equation is solved by a convex splitting method. We show that the method is stable under certain conditions. The linearized schemes are easy to implement and introduce only mild CFL time constraint. Numerical tests are carried out to verify the accuracy, stability and efficiency of the schemes. The method allows us to simulate the interface problems with extremely small interface thickness. Three dimensional simulations are included to validate the efficiency of the method. © 2014 Elsevier Inc.

An efficient scheme for a phase field model for the moving contact line problem with variable density and viscosity

KAUST Repository

Gao, Min; Wang, Xiao-Ping

2014-01-01

In this paper, we develop an efficient numerical method for the two phase moving contact line problem with variable density, viscosity, and slip length. The physical model is based on a phase field approach, which consists of a coupled system of the Cahn-Hilliard and Navier-Stokes equations with the generalized Navier boundary condition [1,2,5]. To overcome the difficulties due to large density and viscosity ratio, the Navier-Stokes equations are solved by a splitting method based on a pressure Poisson equation [11], while the Cahn-Hilliard equation is solved by a convex splitting method. We show that the method is stable under certain conditions. The linearized schemes are easy to implement and introduce only mild CFL time constraint. Numerical tests are carried out to verify the accuracy, stability and efficiency of the schemes. The method allows us to simulate the interface problems with extremely small interface thickness. Three dimensional simulations are included to validate the efficiency of the method. © 2014 Elsevier Inc.

The process model of problem solving difficulty

NARCIS (Netherlands)

Pala, O.; Rouwette, E.A.J.A.; Vennix, J.A.M.

2002-01-01

Groups and organizations, or in general multi-actor decision-making groups, frequently come across complex problems in which neither the problem definition nor the interrelations of parts that make up the problem are well defined. In these kinds of situations, members of a decision-making group

Emergent literacy skills, behavior problems and familial antecedents of reading difficulties: a follow-up study of reading achievement from kindergarten to fifth grade.

Science.gov (United States)

Costa, Hugo Câmara; Perdry, Hervé; Soria, Carmen; Pulgar, Salomé; Cusin, Françoise; Dellatolas, Georges

2013-03-01

This study examined the relation between emergent literacy skills, teachers' reports of behavioral problems, and word reading achievement in a community sample of French students. Family background was investigated and included familial antecedents of reading difficulties (Fa/Rd) and parents' educational level. The analyses explored the pattern of concurrent relations between behavioral, familial and emergent literacy measures in a sample of 812 preschoolers, and their predictive power in explaining word reading achievement in a sub-sample of 150 children followed from kindergarten to fifth grade. Word reading at fifth grade was predicted by kindergarten measures of phonological awareness and letter knowledge. Teachers' reports of inattention symptoms at each grade level were associated with early reading skills and with subsequent word reading. Fa/Rd were concurrently and longitudinally associated with emergent literacy skills, teachers' reported inattention and word reading. These results indicate that children with a family history of reading difficulties are at increased risk for the co-occurrence of reading difficulties and attention problems from kindergarten onward. These findings confirm the shared influence of Fa/Rd on the comorbidity between inattention symptoms and reading difficulties in a non-diagnosed community sample of preschool children followed through late elementary school. Copyright © 2012 Elsevier Ltd. All rights reserved.

Gaussian variable neighborhood search for the file transfer scheduling problem

Directory of Open Access Journals (Sweden)

Dražić Zorica

2016-01-01

Full Text Available This paper presents new modifications of Variable Neighborhood Search approach for solving the file transfer scheduling problem. To obtain better solutions in a small neighborhood of a current solution, we implement two new local search procedures. As Gaussian Variable Neighborhood Search showed promising results when solving continuous optimization problems, its implementation in solving the discrete file transfer scheduling problem is also presented. In order to apply this continuous optimization method to solve the discrete problem, mapping of uncountable set of feasible solutions into a finite set is performed. Both local search modifications gave better results for the large size instances, as well as better average performance for medium and large size instances. One local search modification achieved significant acceleration of the algorithm. The numerical experiments showed that the results obtained by Gaussian modifications are comparable with the results obtained by standard VNS based algorithms, developed for combinatorial optimization. In some cases Gaussian modifications gave even better results. [Projekat Ministarstava nauke Republike Srbije, br. 174010

Workplace bullying and sleep difficulties

DEFF Research Database (Denmark)

Hansen, Åse Marie; Hogh, Annie; Garde, Anne Helene

2014-01-01

PURPOSE: The aims of the present study were to investigate whether being subjected to bullying and witnessing bullying at the workplace was associated with concurrent sleep difficulties, whether frequently bullied/witnesses have more sleep difficulties than occasionally bullied....../witnesses, and whether there were associations between being subjected to bullying or witnessing bullying at the workplace and subsequent sleep difficulties. METHODS: A total of 3,382 respondents (67 % women and 33 % men) completed a baseline questionnaire about their psychosocial work environment and health....... The overall response rate was 46 %. At follow-up 2 years later, 1671 of those responded to a second questionnaire (49 % of the 3,382 respondents at baseline). Sleep difficulties were measured in terms of disturbed sleep, awakening problems, and poor quality of sleep. RESULTS: Bullied persons and witnesses...

Interpersonal dysfunction and affect-regulation difficulties in disordered eating among men and women.

Science.gov (United States)

Ambwani, Suman; Slane, Jennifer D; Thomas, Katherine M; Hopwood, Christopher J; Grilo, Carlos M

2014-12-01

Although several studies suggest that negative affect and interpersonal problems serve as important contributors for eating-related problems, much of this research has been conducted among women and less is known about their roles in precipitating and maintaining eating problems among men. Previous studies with undergraduate men suggest that difficulties in emotion regulation are associated with disordered eating even after controlling for differences in body mass index (BMI) and negative affect. The present study sought to replicate these findings and extend them to assess any unique variance explained by problems in interpersonal functioning among both men and women. Participants were men (n=213) and women (n=521) undergraduates at a large Midwestern university who completed a demographic information form, the Eating Disorder Examination-Questionnaire (EDE-Q), the Difficulties in Emotion Regulation Scale (DERS), the Positive and Negative Affect Schedule, and the Inventory of Interpersonal Problems-Short Circumplex Form (IIP-SC). A series of hierarchical regression analyses indicated that DERS and IIP-SC significantly predicted EDE-Q global scores after controlling for variability in BMI and negative affect and that the results were similar for men and women. Our findings offer preliminary support for models that highlight emotional vulnerability and interpersonal problems for disordered eating for young adult men. Future research extending these findings among treatment-seeking samples and employing multi-method assessment would serve to further clarify the tenability of these theoretical models for both men and women. Copyright © 2014 Elsevier Ltd. All rights reserved.

Graphical modeling for item difficulty in medical faculty exams

African Journals Online (AJOL)

. Conclusion: The ... difficulty criteria. Key words: Item difficulty, quality control, statistical process control, variable control charts ..... assumed that 68% of the values fall in the interval ± 1.S; .... The balance of the construction of items of exam has ...

Evidence-based interventions for reading and language difficulties: creating a virtuous circle.

Science.gov (United States)

Snowling, Margaret J; Hulme, Charles

2011-03-01

BACKGROUND. Children may experience two very different forms of reading problem: decoding difficulties (dyslexia) and reading comprehension difficulties. Decoding difficulties appear to be caused by problems with phonological (speech sound) processing. Reading comprehension difficulties in contrast appear to be caused by problems with 'higher level' language difficulties including problems with semantics (including deficient knowledge of word meanings) and grammar (knowledge of morphology and syntax). AIMS. We review evidence concerning the nature, causes of, and treatments for children's reading difficulties. We argue that any well-founded educational intervention must be based on a sound theory of the causes of a particular form of learning difficulty, which in turn must be based on an understanding of how a given skill is learned by typically developing children. Such theoretically motivated interventions should in turn be evaluated in randomized controlled trials (RCTs) to establish whether they are effective, and for whom. RESULTS. There is now considerable evidence showing that phonologically based interventions are effective in ameliorating children's word level decoding difficulties, and a smaller evidence base showing that reading and oral language (OL) comprehension difficulties can be ameliorated by suitable interventions to boost vocabulary and broader OL skills. CONCLUSIONS. The process of developing theories about the origins of children's educational difficulties and evaluating theoretically motivated treatments in RCTs, produces a 'virtuous circle' whereby theory informs practice, and the evaluation of effective interventions in turn feeds back to inform and refine theories about the nature and causes of children's reading and language difficulties. ©2010 The British Psychological Society.

Children with language problems in a speech and hearing clinic : Background variables and extent of language problems

NARCIS (Netherlands)

Keegstra, A.L.; Knijff, W.A.; Post, W.J.; Goorhuis-Brouwer, S.M.

Objective: Analysis of a clinical population referred for language analysis in terms of background variables and extent of language problems. Design: Descriptive study. Materials and methods: Children referred to a speech and hearing clinic because of assumed language problems were analyzed with

Communication difficulties in teenagers with health impairments

Directory of Open Access Journals (Sweden)

Samokhvalova, Anna G.

2016-09-01

Full Text Available Contemporary psychological and pedagogical studies pay special attention to the socialization of physically impaired children, inclusive education and methods of providing such children with a safe environment to assist in their development. However, difficulties in interpersonal communication experienced by children with health impairments have remained beyond the research scope. The authors conducted a comparative analysis of communication difficulties in typically developed teenagers aged 12-13 years (n = 100 and the problems faced by their peers with visual (n = 30, auditory (n = 30, speech (n = 25 and motor (n = 15 impairments. Actual communication difficulties in teenagers were studied in two ways: the subjective component of impaired communication was registered through a content analysis of a sentence completion test and the objective manifestations of impaired communication were identified through expert evaluation of children’s communicative behavior (educators and psychologists who had been in close contact with the teenagers acted as experts. First, the authors identified typical standard communication problems that were characteristic of teenagers aged 12-13 years, that is, problems with aggression, tolerance, the ability to admit wrongdoing and make concessions, empathy, self-control, self-analysis and self-expression in communication. Second, typical communication difficulties characteristic of physically impaired children were revealed: failure to understand meaning; feelings of awkwardness and shame of oneself; expectations of a negative attitude toward oneself; gelotophobia; and manifestations of despotism, petulance and egotism as defensive reactions in situations of impaired communication. Third, the authors described specific communication difficulties in teenagers with auditory, visual, speech and motor impairments.

Behavioral Problems and Emotional Difficulties at Children and Early Adolescents of the Veterans of War with Post-Traumatic Stress Disorder.

Science.gov (United States)

Selimbasic, Zihnet; Sinanovic, Osman; Avdibegovic, Esmina; Brkic, Maja; Hamidovic, Jasmin

2017-02-01

Behavioral problems and emotional difficulties at children of the veterans of war with post-traumatic stress disorder (PTSD) have not been researched entirely. In our country, which has a lot of persons suffering from some psychological traumas, this trauma seems to continue. The aim of this study was to determine the exposure, manifestations of behavioral problems and emotional difficulties at children and early adolescents, whose fathers were the veterans of war demonstrating post-traumatic stress disorder symptoms. The analyzed group comprised 120 school age children (10-15 years of age), whose parents/fathers were the veterans of war. The children were divided into two groups, and each group into the following two age sub-groups: 10-12 (children) and 13-15 (early adolescents) according to PTSD presence at their fathers - veterans of war. PTSD symptoms at fathers, veterans of war, were assessed using the Harvard Trauma Questionnaire-Bosnia and Herzegovina version and MKB-10 - audit of criteria. To assess the behavioral problems of children, the Child Behavior Checklist for parents was used, and to evaluate the neuroticism at children Hanes-Scale of neuroticism-extraversion was used while the depression level was evaluated using the Depression self-rating scale (DSRS). To analyze the obtained results, SPSS 17 program was used. The value p post-traumatic stress disorder show significant difference at neuroticism sub-scales (ppost-traumatic stress disorder show significant differences in competencies, behavior, emotional difficulties and neuroticism. Significant correlation was found between psychopathology of parents - fathers the veterans of war and their children. Impact of psychological conditions of fathers - the veterans of war with post-traumatic stress disorder to children is strong and they represent a significant risky group for development of mental disorders.

[Medical surveillance in university: organizational difficulties, legal problems, scientific e technical specificities. Experience of University of Milan Bicocca].

Science.gov (United States)

D'Orso, M I; Giuliani, C; Assini, R; Riva, M A; Cesana, G

2012-01-01

Our research describes activities of Occupational Health carried out during last year in University of Milan Bicocca by Occupational Doctors. We describe results of medical surveillance in 1153 employees or students exposed to occupational risks for health and safety. We report results obtained, technical difficulties, organizational problems, and preventive actions decided to improve functionality of our activity. Students seem to be less protected and consequently seem to have higher professional safety and health risks.

Solving the Omitted Variables Problem of Regression Analysis Using the Relative Vertical Position of Observations

Directory of Open Access Journals (Sweden)

Jonathan E. Leightner

2012-01-01

Full Text Available The omitted variables problem is one of regression analysis’ most serious problems. The standard approach to the omitted variables problem is to find instruments, or proxies, for the omitted variables, but this approach makes strong assumptions that are rarely met in practice. This paper introduces best projection reiterative truncated projected least squares (BP-RTPLS, the third generation of a technique that solves the omitted variables problem without using proxies or instruments. This paper presents a theoretical argument that BP-RTPLS produces unbiased reduced form estimates when there are omitted variables. This paper also provides simulation evidence that shows OLS produces between 250% and 2450% more errors than BP-RTPLS when there are omitted variables and when measurement and round-off error is 1 percent or less. In an example, the government spending multiplier, , is estimated using annual data for the USA between 1929 and 2010.

Managing cognitive difficulties after traumatic brain injury: a review of online resources for families.

Science.gov (United States)

Poulin, Valérie; Dawson, Deirdre R; Bottari, Carolina; Verreault, Cynthia; Turcotte, Samantha; Jean, Alexandra

2018-03-22

To identify and critically appraise the content, readability, reliability and usability of websites providing information for managing cognitive difficulties in everyday life for the families of adults with moderate to severe traumatic brain injury. Systematic searches on the Internet for relevant websites were conducted using five search engines, and through consultation of the lists of resources published on websites of traumatic brain injury organizations. Two team members assessed eligibility of the websites. To be included, they had to provide information related to management of cognitive difficulties following moderate to severe traumatic brain injury, to be in English or French and available free of charge. Two reviewers evaluated each website according to: (1) its readability using Flesch-Kincaid Grade Level; (2) the quality of its content using a checklist of eight recommendations for managing memory, attention and executive function problems; (3) its usability (e.g., clear design) and reliability (e.g., currency of information) using the Minervation Validation Instrument for Health Care Web Sites. Of the 38 websites included, 10 provide specific tips for families that cover several domains of cognitive function, including memory, attention and executive function. The most frequent recommendations focused on the use of environmental supports for memory problems (n = 33 websites). The readability of information is below the recommended grade 7 for only nine of the websites. All sites show acceptable usability, but their quality is variable in terms of reliability of the information. This review provides useful information for selecting online resources to educate families about the management of cognitive difficulties following moderate to severe traumatic brain injury, as a complement to information and training provided by the rehabilitation team. Implications for rehabilitation This review describes standardized criteria for the evaluation of the

Exploring the Impact of Early Decisions in Variable Ordering for Constraint Satisfaction Problems

OpenAIRE

Ortiz-Bayliss, José Carlos; Amaya, Ivan; Conant-Pablos, Santiago Enrique; Terashima-Marín, Hugo

2018-01-01

When solving constraint satisfaction problems (CSPs), it is a common practice to rely on heuristics to decide which variable should be instantiated at each stage of the search. But, this ordering influences the search cost. Even so, and to the best of our knowledge, no earlier work has dealt with how first variable orderings affect the overall cost. In this paper, we explore the cost of finding high-quality orderings of variables within constraint satisfaction problems. We also study differen...

Contextual risk, maternal parenting and adolescent externalizing behaviour problems: the role of emotion regulation.

Science.gov (United States)

Walton, A; Flouri, Eirini

2010-03-01

The objective of this study was to test if emotion regulation mediates the association between mothers' parenting and adolescents' externalizing behaviour problems (conduct problems and hyperactivity). The parenting dimensions were warmth, psychological control and behavioural control (measured with knowledge, monitoring and discipline). Adjustment was made for contextual risk (measured with the number of proximal adverse life events experienced), gender, age and English as an additional language. Data were from a UK community sample of adolescents aged 11-18 from a comprehensive school in a disadvantaged area. At the multivariate level, none of the parenting variables predicted hyperactivity, which was associated only with difficulties in emotion regulation, contextual risk and English as a first language. The parenting variables predicting conduct problems at the multivariate level were warmth and knowledge. Knowledge did not predict emotion regulation. However, warmth predicted emotion regulation, which was negatively associated with conduct problems. Contextual risk was a significant predictor of both difficulties in emotion regulation and externalizing behaviour problems. Its effect on conduct problems was independent of parenting and was not via its association with difficulties in emotion regulation. The findings add to the evidence for the importance of maternal warmth and contextual risk for both regulated emotion and regulated behaviour. The small maternal control effects on both emotion regulation and externalizing behaviour could suggest the importance of paternal control for adolescent outcomes.

Psychological Problems of Children with Learning Difficulties.

Science.gov (United States)

Shaughnessy, Michael F.; Scott, Patricia Carol

The paper presents tips for parents of children with learning problems. It describes the emotional side effects of low achievement which may include low self-esteem, clinical depression, "learned helplessness," suicidal ideation, acting out behavior, low frustration tolerance, guilt feelings, interpersonal problems, withdrawal, running away,…

Mapping area variability in social and behavioural difficulties among Glasgow pre-schoolers: linkage of a survey of pre-school staff with routine monitoring data.

Science.gov (United States)

Barry, S J E; Marryat, L; Thompson, L; Ellaway, A; White, J; McClung, M; Wilson, P

2015-11-01

Social, emotional and behavioural development in early to middle childhood impact upon many outcomes in future life and are influenced by home, neighbourhood and school environments. We used linked data to investigate differences between areas in Glasgow City in level of difficulties in pre-school age children, after consideration of demographics, including area-level deprivation. Pre-school education staff completed Strengths and Difficulties Questionnaires (SDQ) on all children progressing to school from a local authority or partnership (local authority-funded private) pre-school in Glasgow City between 2010 and 2012. These data were linked to individual (age, gender) and area-level (deprivation) demographics from the City Council Education Services Department. Statistical models were fitted to the SDQ scores, adjusting for age, gender, area deprivation, year of school entry, pre-school establishment attended and electoral ward of residence. Correlation between neighbouring wards was incorporated to allow for clustering of scores. Boys and those living in more deprived areas had higher levels of difficulties. Children aged 5.0-5.5 years had fewest difficulties, while the oldest and youngest children had similar levels of difficulties. There were no significant secular trends by year of school entry. There remained differences among areas after adjusting for these variables, with children living in some areas having fewer difficulties than would be expected based on their socio-demographic characteristics. There remained differences in children's levels of difficulties between areas after adjusting for age, gender, area deprivation and year of school entry. Children in some very deprived areas had fewer difficulties than might be expected, while those in relatively affluent areas had more difficulties than expected based on their deprivation level. There may be other, unmeasured, individual- and area-level reasons for children's level of difficulties, and these

Identifying the most informative variables for decision-making problems – a survey of recent approaches and accompanying problems

Czech Academy of Sciences Publication Activity Database

Pudil, Pavel; Somol, Petr

2008-01-01

Roč. 16, č. 4 (2008), s. 37-55 ISSN 0572-3043 R&D Projects: GA MŠk 1M0572 Grant - others:GA MŠk(CZ) 2C06019 Institutional research plan: CEZ:AV0Z10750506 Keywords : variable selection * decision making Subject RIV: BD - Theory of Information http://library.utia.cas.cz/separaty/2008/RO/pudil-identifying%20the%20most%20informative%20variables%20for%20decision- making %20problems%20a%20survey%20of%20recent%20approaches%20and%20accompanying%20problems.pdf

Investigating Factorial Invariance of Latent Variables Across Populations When Manifest Variables Are Missing Completely.

Science.gov (United States)

Widaman, Keith F; Grimm, Kevin J; Early, Dawnté R; Robins, Richard W; Conger, Rand D

2013-07-01

Difficulties arise in multiple-group evaluations of factorial invariance if particular manifest variables are missing completely in certain groups. Ad hoc analytic alternatives can be used in such situations (e.g., deleting manifest variables), but some common approaches, such as multiple imputation, are not viable. At least 3 solutions to this problem are viable: analyzing differing sets of variables across groups, using pattern mixture approaches, and a new method using random number generation. The latter solution, proposed in this article, is to generate pseudo-random normal deviates for all observations for manifest variables that are missing completely in a given sample and then to specify multiple-group models in a way that respects the random nature of these values. An empirical example is presented in detail comparing the 3 approaches. The proposed solution can enable quantitative comparisons at the latent variable level between groups using programs that require the same number of manifest variables in each group.

Students’ Covariational Reasoning in Solving Integrals’ Problems

Science.gov (United States)

Harini, N. V.; Fuad, Y.; Ekawati, R.

2018-01-01

Covariational reasoning plays an important role to indicate quantities vary in learning calculus. This study investigates students’ covariational reasoning during their studies concerning two covarying quantities in integral problem. Six undergraduate students were chosen to solve problems that involved interpreting and representing how quantities change in tandem. Interviews were conducted to reveal the students’ reasoning while solving covariational problems. The result emphasizes that undergraduate students were able to construct the relation of dependent variables that changes in tandem with the independent variable. However, students faced difficulty in forming images of continuously changing rates and could not accurately apply the concept of integrals. These findings suggest that learning calculus should be increased emphasis on coordinating images of two quantities changing in tandem about instantaneously rate of change and to promote conceptual knowledge in integral techniques.

Small Scale Variability and the Problem of Data Validation

Science.gov (United States)

Sparling, L. C.; Avallone, L.; Einaudi, Franco (Technical Monitor)

2000-01-01

Numerous measurements taken with a variety of airborne, balloon borne and ground based instruments over the past decade have revealed a complex multiscaled 3D structure in both chemical and dynamical fields in the upper troposphere/lower stratosphere. The variability occurs on scales that are well below the resolution of satellite measurements, leading to problems in measurement validation. We discuss some statistical ideas that can shed some light on the contribution of the natural variability to the inevitable differences in correlative measurements that are not strictly colocated, or that have different spatial resolution.

A duality approach for solving bounded linear programming problems with fuzzy variables based on ranking functions and its application in bounded transportation problems

Science.gov (United States)

Ebrahimnejad, Ali

2015-08-01

There are several methods, in the literature, for solving fuzzy variable linear programming problems (fuzzy linear programming in which the right-hand-side vectors and decision variables are represented by trapezoidal fuzzy numbers). In this paper, the shortcomings of some existing methods are pointed out and to overcome these shortcomings a new method based on the bounded dual simplex method is proposed to determine the fuzzy optimal solution of that kind of fuzzy variable linear programming problems in which some or all variables are restricted to lie within lower and upper bounds. To illustrate the proposed method, an application example is solved and the obtained results are given. The advantages of the proposed method over existing methods are discussed. Also, one application of this algorithm in solving bounded transportation problems with fuzzy supplies and demands is dealt with. The proposed method is easy to understand and to apply for determining the fuzzy optimal solution of bounded fuzzy variable linear programming problems occurring in real-life situations.

Possibility/Necessity-Based Probabilistic Expectation Models for Linear Programming Problems with Discrete Fuzzy Random Variables

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Hideki Katagiri

2017-10-01

Full Text Available This paper considers linear programming problems (LPPs where the objective functions involve discrete fuzzy random variables (fuzzy set-valued discrete random variables. New decision making models, which are useful in fuzzy stochastic environments, are proposed based on both possibility theory and probability theory. In multi-objective cases, Pareto optimal solutions of the proposed models are newly defined. Computational algorithms for obtaining the Pareto optimal solutions of the proposed models are provided. It is shown that problems involving discrete fuzzy random variables can be transformed into deterministic nonlinear mathematical programming problems which can be solved through a conventional mathematical programming solver under practically reasonable assumptions. A numerical example of agriculture production problems is given to demonstrate the applicability of the proposed models to real-world problems in fuzzy stochastic environments.

Exploring the Impact of Early Decisions in Variable Ordering for Constraint Satisfaction Problems

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José Carlos Ortiz-Bayliss

2018-01-01

Full Text Available When solving constraint satisfaction problems (CSPs, it is a common practice to rely on heuristics to decide which variable should be instantiated at each stage of the search. But, this ordering influences the search cost. Even so, and to the best of our knowledge, no earlier work has dealt with how first variable orderings affect the overall cost. In this paper, we explore the cost of finding high-quality orderings of variables within constraint satisfaction problems. We also study differences among the orderings produced by some commonly used heuristics and the way bad first decisions affect the search cost. One of the most important findings of this work confirms the paramount importance of first decisions. Another one is the evidence that many of the existing variable ordering heuristics fail to appropriately select the first variable to instantiate. Another one is the evidence that many of the existing variable ordering heuristics fail to appropriately select the first variable to instantiate. We propose a simple method to improve early decisions of heuristics. By using it, performance of heuristics increases.

Exploring the Impact of Early Decisions in Variable Ordering for Constraint Satisfaction Problems.

Science.gov (United States)

Ortiz-Bayliss, José Carlos; Amaya, Ivan; Conant-Pablos, Santiago Enrique; Terashima-Marín, Hugo

2018-01-01

When solving constraint satisfaction problems (CSPs), it is a common practice to rely on heuristics to decide which variable should be instantiated at each stage of the search. But, this ordering influences the search cost. Even so, and to the best of our knowledge, no earlier work has dealt with how first variable orderings affect the overall cost. In this paper, we explore the cost of finding high-quality orderings of variables within constraint satisfaction problems. We also study differences among the orderings produced by some commonly used heuristics and the way bad first decisions affect the search cost. One of the most important findings of this work confirms the paramount importance of first decisions. Another one is the evidence that many of the existing variable ordering heuristics fail to appropriately select the first variable to instantiate. Another one is the evidence that many of the existing variable ordering heuristics fail to appropriately select the first variable to instantiate. We propose a simple method to improve early decisions of heuristics. By using it, performance of heuristics increases.

Managing social difficulties: roles and responsibilities of patients and staff.

Science.gov (United States)

Wright, Penny; Bingham, Laura; Taylor, Sally; Hanif, Naheed; Podmore, Emma; Velikova, Galina

2012-01-01

Implementation of guidance on assessment and management of psychosocial and supportive-care problems or needs will be successful only if consideration is given to existing skills, experience and expectations of staff and patients. This study examines the roles and responsibilities of staff, patients and families in relation to management of social difficulties and proposes a pathway for response. A qualitative study was performed using staff and patient interviews. Seventeen doctors and 16 nurses were interviewed using patient scenarios and a support service questionnaire. Patients (n = 41) completed a screening questionnaire (the Social Difficulties Inventory) and were interviewed. Interviews were audio-recorded, transcribed and subjected to a Framework analysis. Analysis examined (1) actions taken by staff and patients in response to social difficulties, (2) reasons given for action taken and (3) perceptions of staff and patients of who was responsible for taking action. Staff were confident concerning clinically related issues (i.e. mobility) but more hesitant concerning difficulties related to money, work and family concerns. Patients liked to cope with problems on their own where possible, would have liked information or support from staff but were uncertain how to access this. Results led to development of a hierarchy of interventions in response to detected social difficulties. For routine assessment of social difficulties, patients, nurses and doctors will have to work collaboratively, with nurses taking a lead in discussion. For specific clinically related problems doctors would play a more primary role. Copyright © 2010 John Wiley & Sons, Ltd.

Assessment of Pragmatic Difficulties and Socioemotional Adjustment in Practice

Science.gov (United States)

Farmer, Marion; Oliver, Alice

2005-01-01

Background: In professional practice, psychologists and other professionals such as therapists and teachers receive referrals of many children who present with social, emotional and behavioural difficulties that are difficult to understand and assess. The problems of some of these children may stem from pragmatic difficulties in communication.…

Solving quantum optimal control problems using Clebsch variables and Lin constraints

Science.gov (United States)

Delgado-Téllez, M.; Ibort, A.; Rodríguez de la Peña, T.

2018-01-01

Clebsch variables (and Lin constraints) are applied to the study of a class of optimal control problems for affine-controlled quantum systems. The optimal control problem will be modelled with controls defined on an auxiliary space where the dynamical group of the system acts freely. The reciprocity between both theories: the classical theory defined by the objective functional and the quantum system, is established by using a suitable version of Lagrange’s multipliers theorem and a geometrical interpretation of the constraints of the system as defining a subspace of horizontal curves in an associated bundle. It is shown how the solutions of the variational problem defined by the objective functional determine solutions of the quantum problem. Then a new way of obtaining explicit solutions for a family of optimal control problems for affine-controlled quantum systems (finite or infinite dimensional) is obtained. One of its main advantages, is the the use of Clebsch variables allows to compute such solutions from solutions of invariant problems that can often be computed explicitly. This procedure can be presented as an algorithm that can be applied to a large class of systems. Finally, some simple examples, spin control, a simple quantum Hamiltonian with an ‘Elroy beanie’ type classical model and a controlled one-dimensional quantum harmonic oscillator, illustrating the main features of the theory, will be discussed.

Effects of Mathematics Anxiety and Mathematical Metacognition on Word Problem Solving in Children with and without Mathematical Learning Difficulties

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Lai, Yinghui; Zhu, Xiaoshuang; Chen, Yinghe; Li, Yanjun

2015-01-01

Mathematics is one of the most objective, logical, and practical academic disciplines. Yet, in addition to cognitive skills, mathematical problem solving also involves affective factors. In the current study, we first investigated effects of mathematics anxiety (MA) and mathematical metacognition on word problem solving (WPS). We tested 224 children (116 boys, M = 10.15 years old, SD = 0.56) with the Mathematics Anxiety Scale for Children, the Chinese Revised-edition Questionnaire of Pupil’s Metacognitive Ability in Mathematics, and WPS tasks. The results indicated that mathematical metacognition mediated the effect of MA on WPS after controlling for IQ. Second, we divided the children into four mathematics achievement groups including high achieving (HA), typical achieving (TA), low achieving (LA), and mathematical learning difficulty (MLD). Because mathematical metacognition and MA predicted mathematics achievement, we compared group differences in metacognition and MA with IQ partialled out. The results showed that children with MLD scored lower in self-image and higher in learning mathematics anxiety (LMA) than the TA and HA children, but not in mathematical evaluation anxiety (MEA). MLD children’s LMA was also higher than that of their LA counterparts. These results provide insight into factors that may mediate poor WPS performance which emerges under pressure in mathematics. These results also suggest that the anxiety during learning mathematics should be taken into account in mathematical learning difficulty interventions. PMID:26090806

Effects of Mathematics Anxiety and Mathematical Metacognition on Word Problem Solving in Children with and without Mathematical Learning Difficulties.

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Yinghui Lai

Full Text Available Mathematics is one of the most objective, logical, and practical academic disciplines. Yet, in addition to cognitive skills, mathematical problem solving also involves affective factors. In the current study, we first investigated effects of mathematics anxiety (MA and mathematical metacognition on word problem solving (WPS. We tested 224 children (116 boys, M = 10.15 years old, SD = 0.56 with the Mathematics Anxiety Scale for Children, the Chinese Revised-edition Questionnaire of Pupil's Metacognitive Ability in Mathematics, and WPS tasks. The results indicated that mathematical metacognition mediated the effect of MA on WPS after controlling for IQ. Second, we divided the children into four mathematics achievement groups including high achieving (HA, typical achieving (TA, low achieving (LA, and mathematical learning difficulty (MLD. Because mathematical metacognition and MA predicted mathematics achievement, we compared group differences in metacognition and MA with IQ partialled out. The results showed that children with MLD scored lower in self-image and higher in learning mathematics anxiety (LMA than the TA and HA children, but not in mathematical evaluation anxiety (MEA. MLD children's LMA was also higher than that of their LA counterparts. These results provide insight into factors that may mediate poor WPS performance which emerges under pressure in mathematics. These results also suggest that the anxiety during learning mathematics should be taken into account in mathematical learning difficulty interventions.

Effects of Mathematics Anxiety and Mathematical Metacognition on Word Problem Solving in Children with and without Mathematical Learning Difficulties.

Science.gov (United States)

Lai, Yinghui; Zhu, Xiaoshuang; Chen, Yinghe; Li, Yanjun

2015-01-01

Mathematics is one of the most objective, logical, and practical academic disciplines. Yet, in addition to cognitive skills, mathematical problem solving also involves affective factors. In the current study, we first investigated effects of mathematics anxiety (MA) and mathematical metacognition on word problem solving (WPS). We tested 224 children (116 boys, M = 10.15 years old, SD = 0.56) with the Mathematics Anxiety Scale for Children, the Chinese Revised-edition Questionnaire of Pupil's Metacognitive Ability in Mathematics, and WPS tasks. The results indicated that mathematical metacognition mediated the effect of MA on WPS after controlling for IQ. Second, we divided the children into four mathematics achievement groups including high achieving (HA), typical achieving (TA), low achieving (LA), and mathematical learning difficulty (MLD). Because mathematical metacognition and MA predicted mathematics achievement, we compared group differences in metacognition and MA with IQ partialled out. The results showed that children with MLD scored lower in self-image and higher in learning mathematics anxiety (LMA) than the TA and HA children, but not in mathematical evaluation anxiety (MEA). MLD children's LMA was also higher than that of their LA counterparts. These results provide insight into factors that may mediate poor WPS performance which emerges under pressure in mathematics. These results also suggest that the anxiety during learning mathematics should be taken into account in mathematical learning difficulty interventions.

Validating office-based screening for psychosocial strengths and difficulties among youths in foster care.

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Jee, Sandra H; Szilagyi, Moira; Conn, Anne-Marie; Nilsen, Wendy; Toth, Sheree; Baldwin, Constance D; Szilagyi, Peter G

2011-05-01

To assess the effectiveness of social-emotional screening in the primary care setting for youths in foster care. The setting was a primary care practice for all youth in home-based foster care in 1 county. Subjects were youths, aged 11 to 17 years, and their foster parents; both completed a Strengths and Difficulties Questionnaire at well-child visits. The Strengths and Difficulties Questionnaire is a previously validated 25-item tool that has 5 domains: emotional symptoms; conduct problems; hyperactivity/inattention; peer problems; and prosocial behaviors and an overall total difficulties score. We first compared youth versus parent Strengths and Difficulties Questionnaire scores and then assessed the accuracy of these Strengths and Difficulties Questionnaire scores by comparing them in a subsample of youths (n = 50) with results of home-based structured clinical interviews using the Children's Interview for Psychiatric Syndromes. Of 138 subjects with both youth and parent reports, 78% had prosocial behaviors (strengths), and 70% had 1 or more social-emotional problems. Parents reported significantly more conduct problems (38% vs 16%; P youth. The Strengths and Difficulties Questionnaire had better agreement with the Children's Interview for Psychiatric Syndromes (n = 50) for any Strengths and Difficulties Questionnaire-identified problem for combined youth and foster-parent reports (93%), compared with youth report alone (54%) or parent report alone (71%). Although most youths in foster care have social-emotional problems, most have strengths as well. Youth and foster-parent perspectives on these problems differ. Systematic social-emotional screening in primary care that includes both youth and parent reports can identify youths who may benefit from services.

NEW CONTRIBUTIONS TO READING DIFFICULTIES INTERVENTION

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VÍCTOR SANTIUSTE BERMEJO

2005-01-01

Full Text Available This article presents a synthesis of the intervention programs and strategies to treat reading difficulties. The synthesisincludes a review of the last published articles on the issue, both in Spanish and English. It also presents the visits todifferent Language Rehabilitation Centers in the Community of Madrid including the approaches applied in thesecenters. Besides the description of the general intervention strategies applied to reading problems, some of theprograms to treat specific difficulties of words decoding and recognizing are explained, and the programs to treatreading comprehension and fluidity.

Early Writing Deficits in Preschoolers with Oral Language Difficulties

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Puranik, Cynthia S.; Lonigan, Christopher J.

2012-01-01

The purpose of this study was to investigate whether preschool children with language impairments (LI), a group with documented reading difficulties, also experience writing difficulties. In addition, a purpose was to examine if the writing outcomes differed when children had concomitant cognitive deficits in addition to oral language problems. A…

[Correlation between adolescents psychical disorders and their difficulties of psychosocial adaptation].

Science.gov (United States)

Markeviciūte, Aurelija; Kalkyte, Rūta; Adomaitiene, Virginija; Gudiene, Devika; Velaviciene, Dalia

2007-01-01

To study the correlation between adolescents' psychical disorders and their difficulties of psychosocial adaptation. There were 63 adolescent participants in our study (47 girls and 16 boys) who were hospitalized in Department of Children and Adolescent Psychiatry, Kaunas University of Medicine Hospital (Lithuania) during the period from September to December, 2005. Twenty-seven adolescents (19 girls and 8 boys) had suicidal and self-harming behavior. Psychical disorders were diagnosed according to ICD-10 diagnostic criterions. We used Strengths and Difficulties Questionnaire SDQ-lit adapted for Lithuania. While comparing the mean scores in both sexes of adolescents with diagnoses of depressive, behavioral and adaptation disturbances, we found a statistically significant difference only in emotionally disturbance scale results (p=0.016). Analyzing groups of girls and boys separately, girls showed to be worse psychosocially adapted and had more emotional problems. Girls who tried to commit suicide had more emotional (p=0.006) and psychosocial problems (padaptation (p=0.031) difficulties. Parents noted that those who committed a suicide and had behavior disturbances had more expressed emotional (p=0.007) and general adaptation (p=0.053) problems. 1. Adolescent girls who were diagnosed depressive illnesses had more emotional and general adaptation problems than girls who were diagnosed behavior or adaptation disorders. 2. Adolescent girls who tried to commit suicide had more expressed behavior problems and difficulties of emotional, general adaptation. 3. Most expressed difficulties of emotional and general adaptation were typical to girls who were diagnosed with depression and who tried to commit a suicide.

Variable order one-step methods for initial value problems I ...

African Journals Online (AJOL)

A class of variable order one-step integrators is proposed for Initial Value Problems (IVPs) in Ordinary Differential Equations (ODEs). It is based on a rational interpolant. Journal of the Nigerian Association of Mathematical Physics Vol. 10 2006: pp. 91-96 ...

A Variable Neighborhood Search Algorithm for the Leather Nesting Problem

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Cláudio Alves

2012-01-01

Full Text Available The leather nesting problem is a cutting and packing optimization problem that consists in finding the best layout for a set of irregular pieces within a natural leather hide with an irregular surface and contour. In this paper, we address a real application of this problem related to the production of car seats in the automotive industry. The high quality requirements imposed on these products combined with the heterogeneity of the leather hides make the problem very complex to solve in practice. Very few results are reported in the literature for the leather nesting problem. Furthermore, the majority of the approaches impose some additional constraints to the layouts related to the particular application that is considered. In this paper, we describe a variable neighborhood search algorithm for the general leather nesting problem. To evaluate the performance of our approaches, we conducted an extensive set of computational experiments on real instances. The results of these experiments are reported at the end of the paper.

A Study of Moroccan Pupils' Difficulties at Second Baccalaureate Year in Solving Chemistry Problems Relating to the Reactivity of Ethanoate Ions and to Copper-Aluminium Cells

Science.gov (United States)

Ouasri, Ali

2017-01-01

This paper investigates the difficulties that Moroccan pupils (18-19) of the second Baccalaureate year encountered in solving chemical equilibrium problems relating to ethanoate ions' reactivity with water and methanoic acid, and to copper-aluminum cells. The pupils were asked to provide answers to questions derived from two problems. The…

Perceived difficulty quitting predicts enrollment in a smoking-cessation program for patients with head and neck cancer.

Science.gov (United States)

Duffy, Sonia A; Scheumann, Angela L; Fowler, Karen E; Darling-Fisher, Cynthia; Terrell, Jeffrey E

2010-05-01

To determine the predictors of participation in a smoking-cessation program among patients with head and neck cancer. This cross-sectional study is a substudy of a larger, randomized trial of patients with head and neck cancer that determined the predictors of smokers' participation in a cessation intervention. Otolaryngology clinics at three Veterans Affairs medical centers (Ann Arbor, MI, Gainesville, FL, and Dallas, TX), and the University of Michigan Hospital in Ann Arbor. 286 patients who had smoked within six months of the screening survey were eligible for a smoking-cessation intervention. Descriptive statistics and bivariate and multivariate logistic regression were used to determine the independent predictors of smokers' participation in an intervention study. Perceived difficulty quitting (as a construct of self-efficacy), health behaviors (i.e., smoking and problem drinking), clinical characteristics (i.e., depression and cancer site and stage), and demographic variables. Forty-eight percent of those eligible participated. High perceived difficulty quitting was the only statistically significant predictor of participation, whereas problem drinking, lower depressive symptoms, and laryngeal cancer site approached significance. Special outreach may be needed to reach patients with head and neck cancer who are overly confident in quitting, problem drinkers, and patients with laryngeal cancer. Oncology nurses are in an opportune position to assess patients' perceived difficulty quitting smoking and motivate them to enroll in cessation programs, ultimately improving quality of life, reducing risk of recurrence, and increasing survival for this population.

Working in Dyads and Alone: Examining Process Variables in Solving Insight Problems

Science.gov (United States)

Tidikis, Viktoria; Ash, Ivan K.

2013-01-01

This study investigated the effects of working in dyads and their associated gender composition on performance (solution rate and time) and process variables (number of impasses, number of passed solutions, and number of problem solving suggestions and interactions) in a set of classic insight problem solving tasks. Two types of insight problems…

Beyond Psychometrics: The Difference between Difficult Problem Solving and Complex Problem Solving

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Jens F. Beckmann

2017-10-01

Full Text Available In this paper we argue that a synthesis of findings across the various sub-areas of research in complex problem solving and consequently progress in theory building is hampered by an insufficient differentiation of complexity and difficulty. In the proposed framework of person, task, and situation (PTS, complexity is conceptualized as a quality that is determined by the cognitive demands that the characteristics of the task and the situation impose. Difficulty represents the quantifiable level of a person’s success in dealing with such demands. We use the well-documented “semantic effect” as an exemplar for testing some of the conceptual assumptions derived from the PTS framework. We demonstrate how a differentiation between complexity and difficulty can help take beyond a potentially too narrowly defined psychometric perspective and subsequently gain a better understanding of the cognitive mechanisms behind this effect. In an empirical study a total of 240 university students were randomly allocated to one of four conditions. The four conditions resulted from contrasting the semanticity level of the variable labels used in the CPS system (high vs. low and two instruction conditions for how to explore the CPS system’s causal structure (starting with the assumption that all relationships between variables existed vs. starting with the assumption that none of the relationships existed. The variation in the instruction aimed at inducing knowledge acquisition processes of either (1 systematic elimination of presumptions, or (2 systematic compilation of a mental representation of the causal structure underpinning the system. Results indicate that (a it is more complex to adopt a “blank slate” perspective under high semanticity as it requires processes of inhibiting prior assumptions, and (b it seems more difficult to employ a systematic heuristic when testing against presumptions. In combination, situational characteristics, such as the

Analysis of Students’ Difficulties about Rotational Dynamic Topic Based on Resource Theory

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I. Rahmawati

2017-04-01

Full Text Available Students’ difficulties commonly are analyzed based on misconception theory. This paper aimed to analyze students’ difficulties on the rotational dynamic based on resource theory. The subject of research consisted of 108 first-year undergraduate students of Physics Education, State University of Malang. Firstly, the students were asked to solve 15 multiple-choice questions and gave open explanation. We then implemened a constant comparative method to identify and categorize some resources that students employed in solving several problems that most the students failed to respond correctly. The results indicated that the students had difficulties in solving problems related to the torque and the equilibrium of rigid body. The students’ difficulties were not merely caused by the lack of correct knowledge. Instead, they have the correct knowledge or resources but they activated them on inappropriate context. The students will be successfully used the resources to solve problems if they activated them in the right context.

Acceptability and Difficulty of the STEM Track Implementation in Senior High School

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Aldrin John Jao Estonanto

2017-05-01

Full Text Available The Department of Education in the Philippines implemented the Enhanced Basic Education Curriculum in 2013 which led to the creation of Senior High School Program. Studies showed the importance of the support of stakeholders to the success of an educational reform. Thus, it is significant to consider the acceptance of the new curriculum. This descriptive- correlational study sought to determine the acceptability of the Senior High School STEM program and correlate it to the difficulty level of problems along its implementation. Findings showed that there was low acceptability of the new curriculum among stakeholders. It also revealed that the major problems along the implementation of the curriculum were on the areas of Facility and Instructional Materials, and that the difficulty level of the problems was high. Finally, it was found out that there was significant inverse correlation between the curriculum’s acceptability level and the problems’ difficulty level. Thus, the study concludes that the acceptability level of curriculum is significantly related to the difficulty level of the problems encountered by the school along its implementation. The researcher recommends that a series of informationdissemination programs be conducted to raise awareness on the significance of the STEM Curriculum among the stakeholders of the school. Interventions were also proposed to address the problems

Early Identification of Reading Comprehension Difficulties

Science.gov (United States)

Catts, Hugh W.; Nielsen, Diane Corcoran; Bridges, Mindy Sittner; Liu, Yi-Syuan

2016-01-01

Most research on early identification of reading disabilities has focused on word reading problems and little attention has been given to reading comprehension difficulties. In this study, we investigated whether measures of language ability and/or response to language intervention in kindergarten uniquely predicted reading comprehension…

Actigraphic and parental reports of sleep difficulties in children with attention-deficit/hyperactivity disorder

DEFF Research Database (Denmark)

Hvolby, Allan; Jørgensen, Jan; Bilenberg, Niels

2008-01-01

OBJECTIVES: To describe actigraphically detected and parent-reported sleep problems in nonmedicated children with attention-deficit/hyperactivity disorder (ADHD); to clarify whether or not comorbid oppositional defiant disorder contributes to sleep difficulties; and to compare objectively measured...... subjects. Average sleep onset latencies were 26.3 minutes in the ADHD group, 18.6 minutes in the psychiatric control group, and 13.5 minutes in the healthy reference group. There was no apparent relationship between sleep problems and comorbid oppositional defiant disorder. We found discrepancies between...... the objectively measured sleep variables and those reported by parents, who overestimated sleep onset latency. CONCLUSIONS: The results of this study allow us to conclude that some children with ADHD have impaired sleep that cannot be referred to comorbid oppositional defiant disorder. However, it is important...

Variable Neighbourhood Search and Mathematical Programming for Just-in-Time Job-Shop Scheduling Problem

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Sunxin Wang

2014-01-01

Full Text Available This paper presents a combination of variable neighbourhood search and mathematical programming to minimize the sum of earliness and tardiness penalty costs of all operations for just-in-time job-shop scheduling problem (JITJSSP. Unlike classical E/T scheduling problem with each job having its earliness or tardiness penalty cost, each operation in this paper has its earliness and tardiness penalties, which are paid if the operation is completed before or after its due date. Our hybrid algorithm combines (i a variable neighbourhood search procedure to explore the huge feasible solution spaces efficiently by alternating the swap and insertion neighbourhood structures and (ii a mathematical programming model to optimize the completion times of the operations for a given solution in each iteration procedure. Additionally, a threshold accepting mechanism is proposed to diversify the local search of variable neighbourhood search. Computational results on the 72 benchmark instances show that our algorithm can obtain the best known solution for 40 problems, and the best known solutions for 33 problems are updated.

Examining the model structure of the strengths and difficulties questionnaire (SDQ)

OpenAIRE

Azzopardi, Lara Marie; Camilleri, Liberato; Sammut, Fiona; Cefai, Carmel

2016-01-01

The Strengths and Difficulties questionnaire (SDQ), proposed by Goodman 1997, has been used by researchers to measure social, emotional and behaviour difficulties in children. The SDQ includes four difficulty subscales, measuring emotional, conduct, hyperactivity and peer problems. It also includes a fifth subscale, measuring prosocial behaviour. Dickey 2004 suggested that the SDQ factor structure can be reduced to three dimensions comprising the prosocial, externalisation and internalisation...

Preoperative ultrasonography and prediction of technical difficulties during laparoscopic cholecystectomy.

Science.gov (United States)

Daradkeh, S S; Suwan, Z; Abu-Khalaf, M

1998-01-01

A prospective study was carried out to investigate the value of preoperative ultrasound findings for predicting difficulties encountered during laparoscopic cholecystectomy (LC). Altogether 160 consecutive patients with symptomatic gallbladder (GB) disease (130 females, 30 males) referred to the Jordan University Hospital were recruited for the purpose of this study. All patients underwent detailed ultrasound examination 24 hours prior to LC. The overall difficulty score (ODS), as a dependent variable, was based on the following operative parameters: duration of surgery, bleeding, dissection of Calot's triangle, dissection of gallbladder wall, adhesions, spillage of bile, spillage of stone, and difficulty of gallbladder extraction. Multiple regression analysis was used to assess the significance of the following preoperative ultrasound variables (independent) for predicting the variation in the ODS: size of the GB, number of GB stones, size of stones, location of GB stones, thickness of GB wall, common bile duct (CBD) diameter, and liver size. Only thickness of GB wall and CBD diameter were found to be significant predictors of the variation in the ODS (adjusted R2 = 0.25). We conclude that the preoperative ultrasound examination is of value for predicting difficulties encountered during LC, but it is not the sole predictor.

Investigating student difficulties on integral calculus based on critical thinking aspects

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Farida Nursyahidah

2017-11-01

Full Text Available Students of Mathematics education often struggle with integration problem, but yet the root of the problem related to critical thinking is rarely investigated. This article reports research where the first-year students of Mathematics Education of PGRI University Semarang were given an integral problem, then individually they were interviewed related to the answer they have made. The findings of students' difficulties in working on integration problem were confirmed through several questions in the interview which aimed to uncover their critical thinking process related to concepts, procedures, and problem solving. This study shows that student difficulties in Integration by disc method such as failure in identifying radius of a rotary object, specify partition, and integration bounds are closely related to their failure to think critically related to concept, skills, and problem solving aspects of critical thinking.

A multi-level variable neighborhood search heuristic for a practical vehicle routing and driver scheduling problem

DEFF Research Database (Denmark)

Wen, Min; Krapper, Emil; Larsen, Jesper

things, predefined workdays, fixed starting time, maximum weekly working duration, break rule. The objective is to minimize the total delivery cost. The real-life case study is fi rst introduced and modelled as a mixed integer linear program. A multilevel variable neighborhood search heuristic...... is then proposed for the problem. At the first level, the problem size is reduced through an aggregation procedure. At the second level, the aggregated weekly planning problem is decomposed into daily planning problems, each of which is solved by a variable neighborhood search. At the last level, the solution...

Maintenance of extratropical low-frequency variabilities in the atmosphere

International Nuclear Information System (INIS)

Ting, M.

1994-01-01

The extratropical low-frequency variability is one of the most important components in extratropical dynamics. While there are some understanding of the high-frequency, synoptic scale storm track eddy development due to baroclinic instability theory, its low-frequency counterpart is poorly understood and the theory for that is slowly evolving. The main difficulty seems to be lying on the fact that the problem is three dimensional in nature

Inverse Ising problem in continuous time: A latent variable approach

Science.gov (United States)

Donner, Christian; Opper, Manfred

2017-12-01

We consider the inverse Ising problem: the inference of network couplings from observed spin trajectories for a model with continuous time Glauber dynamics. By introducing two sets of auxiliary latent random variables we render the likelihood into a form which allows for simple iterative inference algorithms with analytical updates. The variables are (1) Poisson variables to linearize an exponential term which is typical for point process likelihoods and (2) Pólya-Gamma variables, which make the likelihood quadratic in the coupling parameters. Using the augmented likelihood, we derive an expectation-maximization (EM) algorithm to obtain the maximum likelihood estimate of network parameters. Using a third set of latent variables we extend the EM algorithm to sparse couplings via L1 regularization. Finally, we develop an efficient approximate Bayesian inference algorithm using a variational approach. We demonstrate the performance of our algorithms on data simulated from an Ising model. For data which are simulated from a more biologically plausible network with spiking neurons, we show that the Ising model captures well the low order statistics of the data and how the Ising couplings are related to the underlying synaptic structure of the simulated network.

Cognitive Strategies, Working Memory, and Growth in Word Problem Solving in Children With Math Difficulties.

Science.gov (United States)

Swanson, H Lee; Lussier, Catherine M; Orosco, Michael J

2015-01-01

This study investigated the role of strategy instruction and working memory capacity (WMC) on word problem solving accuracy in children with (n = 100) and without (n = 92) math difficulties (MD). Within classrooms, children in Grades 2 and 3 were randomly assigned to one of four treatment conditions: verbal-only strategies (e.g., underlining question sentence), verbal + visual strategies, visual-only strategies (e.g., correctly placing numbers in diagrams), or untreated control. Strategy interventions included 20 sessions in both Year 1 and Year 2. The intent-to-treat as well as the "as-treated" analyses showed that treatment effects were significantly moderated by WMC. In general, treatment outcomes were higher when WMC was set to a high rather than low level. When set to a relatively high WMC level, children with MD performed significantly better under visual-only strategy conditions and children without MD performed better under verbal + visual conditions when compared to control conditions. © Hammill Institute on Disabilities 2013.

Problems and challenges in social marketing.

Science.gov (United States)

Bloom, P N; Novelli, W D

1981-01-01

This article reviews the problems that arise when general marketing principles are applied to social programs. Social marketing is conceptualized as the design, implementation, and control of programs seeking to increase the acceptability of a social ideal or practice in a target group. These problems can occur in 8 basic decision-making areas: market analysis, market segmentation, product strategy development, pricing strategy development, channel strategy development, communications strategy development, organizational design and planning, and evaluation. Social marketers find that they have less good secondary data about their consumers, more problems obtaining valid and reliable measures of relevant variables, more difficulty sorting out the relative influence of determinants of consumer behavior, and more problems getting consumer research funded than marketers in the commercial sector. They tend to have less flexibility in shaping their products and more difficulty formulating product concepts. Problems associated with establishing, utilizing, and controlling distribution channels comprise another major difference between social and more conventional forms of marketing. Social marketers also find that their communications options are somewhat limited as a result of problems associated with use of paid advertisements, pressures not to use certain types of appeals in their messages, and the need to communicate large amounts of information in their messages. Moreover, social marketers must function in organizations where marketing activities are poorly understood, underappreciated, and inappropriately located. Finally, they face problems trying to define effectiveness measures or estimating the contribution their program has made toward the achievement of certain objectives. If all these problems are anticipated and handled creatively, social marketing efforts can succeed.

Young people with features of gender dysphoria: Demographics and associated difficulties.

Science.gov (United States)

Holt, Vicky; Skagerberg, Elin; Dunsford, Michael

2016-01-01

This article presents the findings from a cross-sectional study on demographic variables and associated difficulties in 218 children and adolescents (Mean age = 14 years, SD = 3.08, range = 5-17 years), with features of gender dysphoria, referred to the Gender Identity Development Service (GIDS) in London during a 1-year period (1 January 2012-31 December 2012). Data were extracted from patient files (i.e. referral letters, clinical notes and clinician reports). The most commonly reported associated difficulties were bullying, low mood/depression and self-harming. There was a gender difference on some of the associated difficulties with reports of self-harm being significantly more common in the natal females and autism spectrum conditions being significantly more common in the natal males. The findings also showed that many of the difficulties increased with age. Findings regarding demographic variables, gender dysphoria, sexual orientation and family features are reported, and limitations and implications of the cross-sectional study are discussed. In conclusion, young people with gender dysphoria often present with a wide range of associated difficulties which clinicians need to take into account, and our article highlights the often complex presentations of these young people. © The Author(s) 2014.

An issue encountered in solving problems in electricity and magnetism: curvilinear coordinates

International Nuclear Information System (INIS)

Gülçiçek, Çağlar; Damlı, Volkan

2016-01-01

In physics lectures on electromagnetic theory and mathematical methods, physics teacher candidates have some difficulties with curvilinear coordinate systems. According to our experience, based on both in-class interactions and teacher candidates’ answers in test papers, they do not seem to have understood the variables in curvilinear coordinate systems very well. For this reason, the problems that physics teacher candidates have with variables in curvilinear coordinate systems have been selected as a study subject. The aim of this study is to find the physics teacher candidates’ problems with determining the variables of drawn shapes, and problems with drawing shapes based on given variables in curvilinear coordinate systems. Two different assessment tests were used in the study to achieve this aim. The curvilinear coordinates drawing test (CCDrT) was used to discover their problems related to drawing shapes, and the curvilinear coordinates detection test (CCDeT) was used to find out about problems related to determining variables. According to the findings obtained from both tests, most physics teacher candidates have problems with the ϕ variable, while they have limited problems with the r variable. Questions that are mostly answered wrongly have some common properties, such as value. According to inferential statistics, there is no significant difference between the means of the CCDeT and CCDrT scores. The mean of the CCDeT scores is only 4.63 and the mean of the CCDrT is only 4.66. Briefly, we can say that most physics teacher candidates have problems with drawing a shape using the variables of curvilinear coordinate systems or in determining the variables of drawn shapes. (paper)

Quantifying siting difficulty: a case study of US transmission line siting

Energy Technology Data Exchange (ETDEWEB)

Vajjhala, S.P. [Resources for the Future, Washington DC (United States); Fischbeck, P.S. [Carnegie Mellon University, Pittsburgh, PA (United States). Departments of Social and Decision Sciences and Engineering and Public Policy

2007-01-15

The worldwide demand for new energy infrastructures has been paralleled in recent years by the increasing difficulty of siting major facilities. Siting difficulty is the subject of widespread discussion, but because of the complexity of the problem, potential solutions are not obvious or well understood. This paper presents a two-step policy-level framework that first develops an empirical measure of siting difficulty and then qualitatively assesses its major causes. The approach is based on the creation and aggregation of four siting indicators that are independent of the common causes and localized effects of siting problems. The proposed framework is demonstrated for the case of US transmission line siting. Results of the analyses reveal significant variations in state siting difficulty and industry experts' perceptions of its dominant causes, with implications for the long-term success of Regional Transmission Organizations (RTOs) and knowledge transfer among siting professionals in the deregulated industry. (author)

Separating variables in two-way diffusion equations

International Nuclear Information System (INIS)

Fisch, N.J.; Kruskal, M.D.

1979-10-01

It is shown that solutions to a class of diffusion equations of the two-way type may be found by a method akin to separation of variables. The difficulty with such equations is that the boundary data must be specified partly as initial and partly as final conditions. In contrast to the one-way diffusion equation, where the solution separates only into decaying eigenfunctions, the two-way equations separate into both decaying and growing eigenfunctions. Criteria are set forth for the existence of linear eigenfunctions, which may not be found directly by separating variables. A speculation with interesting ramifications is that the growing and decaying eigenfunctions are separately complete in an appropriate half of the problem domain

Designs of goal-free problems for trigonometry learning

Science.gov (United States)

Retnowati, E.; Maulidya, S. R.

2018-03-01

This paper describes the designs of goal-free problems particularly for trigonometry, which may be considered a difficult topic for high school students.Goal-free problem is an instructional design developed based on a Cognitive load theory (CLT). Within the design, instead of asking students to solve a specific goal of a mathematics problem, the instruction is to solve as many Pythagoras as possible. It was assumed that for novice students, goal-free problems encourage students to pay attention more to the given information and the mathematical principles that can be applied to reveal the unknown variables. Hence, students develop more structured knowledge while solving the goal-free problems. The resulted design may be used in regular mathematics classroom with some adjustment on the difficulty level and the allocated lesson time.

A Design-Adaptive Local Polynomial Estimator for the Errors-in-Variables Problem

KAUST Repository

Delaigle, Aurore

2009-03-01

Local polynomial estimators are popular techniques for nonparametric regression estimation and have received great attention in the literature. Their simplest version, the local constant estimator, can be easily extended to the errors-in-variables context by exploiting its similarity with the deconvolution kernel density estimator. The generalization of the higher order versions of the estimator, however, is not straightforward and has remained an open problem for the last 15 years. We propose an innovative local polynomial estimator of any order in the errors-in-variables context, derive its design-adaptive asymptotic properties and study its finite sample performance on simulated examples. We provide not only a solution to a long-standing open problem, but also provide methodological contributions to error-invariable regression, including local polynomial estimation of derivative functions.

The difficulties encountered in conversion from classic pancreaticoduodenectomy to total laparoscopic pancreaticoduodenectomy

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Muharrem Battal

2016-01-01

Full Text Available Background: Recently, total laparoscopic pancreatectomy has been performed at many centres as an alternative to open surgery. In this study, we aimed to present the difficulties that we have encountered in converting from classic open pancreaticoduodenectomy to total laparoscopic pancreatectomy. Materials and Methods: Between December 2012 and January 2014, we had 100 open pancreaticoduodenectomies. Subsequently, we tried to perform total laparoscopic pancreaticoduodenectomy (TLPD in 22 patients. In 17 of these 22 patients, we carried out the total laparoscopic procedure. We analysed the difficulties that we encountered converting to TLPD in three parts: Preoperative, operative and postoperative. Preoperative difficulties involved patient selection, preparation of operative instruments, and planning the operation. Operative difficulties involved the position of the trocars, dissection, and reconstruction problems. The postoperative difficulty involved follow-up of the patient. Results: According to our experiences, the most important problem is the proper selection of patients. Contrary to our previous thoughts, older patients who were in better condition were comparatively more appropriate candidates than younger patients. This is because the younger patients have generally soft pancreatic texture, which complicates the reconstruction. The main operative problems are trocar positions and maintaining the appropriate position of the camera, which requires continuous changes in its angles during the operation. However, postoperative follow-up is not very different from the classic procedure. Conclusion: TLPD is a suitable procedure under appropriate conditions.

Heuristics for the Variable Sized Bin Packing Problem Using a Hybrid P-System and CUDA Architecture

OpenAIRE

AlEnezi, Qadha'a; AboElFotoh, Hosam; AlBdaiwi, Bader; AlMulla, Mohammad Ali

2016-01-01

The Variable Sized Bin Packing Problem has a wide range of application areas including packing, scheduling, and manufacturing. Given a list of items and variable sized bin types, the objective is to minimize the total size of the used bins. This problem is known to be NP-hard. In this article, we present two new heuristics for solving the problem using a new variation of P systems with active membranes, which we call a hybrid P system, implemented in CUDA. Our hybrid P-system model allows usi...

Minding the gap: Children's difficulty conceptualizing spatial intervals as linear measurement units.

Science.gov (United States)

Solomon, Tracy L; Vasilyeva, Marina; Huttenlocher, Janellen; Levine, Susan C

2015-11-01

Understanding measurement units is critical to mathematics and science learning, but it is a topic that American students find difficult. In 3 studies, we investigated the challenges underlying this difficulty in kindergarten and second grade by comparing performance on different versions of a linear measurement task. Children measured crayons that were either aligned or shifted relative to the left edge of either a continuous ruler or a row of discrete units. The alignment (aligned, shifted) and the measuring tool (ruler, discrete units) were crossed to form 4 types of problems. Study 1 showed good performance in both grades on both types of aligned problems as well as on the shifted problems with discrete units. In contrast, performance was at chance on the shifted ruler problems. Study 2 showed that performance on shifted discrete unit problems declined when numbers were placed on the units, particularly for kindergarteners, suggesting that on the shifted ruler problems, the presence of numbers may have contributed to children's difficulty. However, Study 3 showed that the difficulty on the shifted ruler problems persisted even when the numbers were removed from the ruler. Taken together, these findings suggest that there are multiple challenges to understanding measurement, but that a key challenge is conceptualizing the ruler as a set of countable spatial interval units. (c) 2015 APA, all rights reserved).

Are externalizing and internalizing difficulties of young children with spelling impairment related to their ADHD symptoms?

Science.gov (United States)

Rietz, Chantal Sabrina; Hasselhorn, Marcus; Labuhn, Andju Sara

2012-08-01

Children with literacy difficulties often suffer from a variety of co-occurring externalizing and internalizing difficulties, as well as comorbid ADHD. Therefore, these externalizing and internalizing problems might be more related to comorbid ADHD, rather than being a correlate of literacy difficulties per se. In the present study, we investigated the occurrence of externalizing and internalizing difficulties in elementary school children (third grade) with and without spelling impairment. Taking the high rate of comorbidity between literacy difficulties and ADHD into account, we investigated whether co-occurring difficulties are associated with spelling impairment per se or with comorbid ADHD symptoms. Results indicated that these young children with spelling impairment showed more co-occurring difficulties compared with children without spelling impairment. Hierarchical regression analysis indicated that occurrence of externalizing symptoms is more strongly related to comorbid ADHD symptoms than to spelling impairment per se. The pattern of results concerning internalizing problems was not as distinct but showed a similar trend. Preferably, carers and educators should be aware of co-occurring socio-emotional and behavioural problems in children with spelling impairment. Particularly children with spelling impairment and comorbid ADHD symptoms seem to have an increased risk of encountering further co-occurring difficulties. Copyright © 2012 John Wiley & Sons, Ltd.

Phenotypic variability in developmental coordination disorder: Clustering of generalized joint hypermobility with attention deficit/hyperactivity disorder, atypical swallowing and narrative difficulties.

Science.gov (United States)

Celletti, Claudia; Mari, Giorgia; Ghibellini, Giulia; Celli, Mauro; Castori, Marco; Camerota, Filippo

2015-03-01

Developmental coordination disorder (DCD) is a recognized childhood disorder mostly characterized by motor coordination difficulties. Joint hypermobility syndrome, alternatively termed Ehlers-Danlos syndrome, hypermobility type (JHS/EDS-HT), is a hereditary connective tissue disorder mainly featuring generalized joint hypermobility (gJHM), musculoskeletal pain, and minor skin features. Although these two conditions seem apparently unrelated, recent evidence highlights a high rate of motor and coordination findings in children with gJHM or JHS/EDS-HT. Here, we investigated the prevalence of gJHM in 41 Italian children with DCD in order to check for the existence of recognizable phenotypic subgroups of DCD in relation to the presence/absence of gJHM. All patients were screened for Beighton score and a set of neuropsychological tests for motor competences (Movement Assessment Battery for Children and Visual-Motor Integration tests), and language and learning difficulties (Linguistic Comprehension Test, Peabody Picture Vocabulary Test, Boston Naming Test, Bus Story Test, and Memoria-Training tests). All patients were also screening for selected JHS/EDS-HT-associated features and swallowing problems. Nineteen (46%) children showed gJHM and 22 (54%) did not. Children with DCD and gJHM showed a significant excess of frequent falls (95 vs. 18%), easy bruising (74 vs. 0%), motor impersistence (89 vs. 23%), sore hands for writing (53 vs. 9%), attention deficit/hyperactivity disorder (89 vs. 36%), constipation (53 vs. 0%), arthralgias/myalgias (58 vs. 4%), narrative difficulties (74 vs. 32%), and atypical swallowing (74 vs. 18%). This study confirms the non-causal association between DCD and gJHM, which, in turn, seems to increase the risk for non-random additional features. The excess of language, learning, and swallowing difficulties in patients with DCD and gJHM suggests a wider effect of lax tissues in the development of the nervous system. © 2015 Wiley Periodicals, Inc.

Mathematics Difficulties: Does One Approach Fit All?

Science.gov (United States)

Gifford, Sue; Rockliffe, Freda

2012-01-01

This article reviews the nature of learning difficulties in mathematics and, in particular, the nature and prevalence of dyscalculia, a condition that affects the acquisition of arithmetical skills. The evidence reviewed suggests that younger children (under the age of 10) often display a combination of problems, including minor physical…

The Investigation of Elementary Mathematics Teacher Candidates' Problem Solving Skills According to Various Variables

Science.gov (United States)

Kaya, Deniz; Izgiol, Dilek; Kesan, Cenk

2014-01-01

The aim was to determine elementary mathematics teacher candidates' problem solving skills and analyze problem solving skills according to various variables. The data were obtained from total 306 different grade teacher candidates receiving education in Department of Elementary Mathematics Education, Buca Faculty of Education, Dokuz Eylul…

Subjective executive difficulties – a study using the Dysexecutive Questionnaire

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Ewa Małgorzata Szepietowska

2018-03-01

Full Text Available Introduction: Subjective executive difficulties, understood as a sense of disruption of planning, control and correction of one’s own activity, is often reported by healthy as well as clinical individuals. Self-report measures such as the Dysexecutive Questionnaire (DEX-S are used to assess the severity of this feeling. The diagnostic value of this method is debated due to the numerous factors affecting the beliefs on executive deficits. Aim of the study: With reference to inconclusive data concerning the underlying factors of subjective executive deficits and the value of self-report measures the following aims of the present study were established: a determination of the demographic, clinical and cognitive characteristics of individuals with various levels of subjective executive difficulties, b finding which of these variables contribute to the risk of subjective executive difficulties increase. Material and methods: The study included 213 adult individuals. DEX-S as well as measures of cognitive assessment (Montreal Cognitive Assessment, MoCA; subtests of the Wechsler Adult Intelligence Scale-Revised, WAIS-R and depressive mood assessment [Geriatric Depression Scale (Short Form, GDS-15] were used. Demographic variables (age, gender and educational level as well as clinical variables (lack of/presence of central nervous system disease history, including lateralised brain pathology were also taken into consideration. Based on DEX-S results a cluster analysis was performed and two groups of subjects with a different level of subjective executive difficulties were identified: low-severity group (individuals reporting no complaints regarding executive deficits and high-severity group (individuals with complaints. Group comparisons demonstrated that individuals complaining about executive deficits have a higher depressive mood index and lower scores on some subtests used to assess cognitive functions. The results of logistic regression analysis

Comparison of different calibration methods suited for calibration problems with many variables

DEFF Research Database (Denmark)

Holst, Helle

1992-01-01

This paper describes and compares different kinds of statistical methods proposed in the literature as suited for solving calibration problems with many variables. These are: principal component regression, partial least-squares, and ridge regression. The statistical techniques themselves do...

Who walks? Factors associated with walking behavior in disabled older women with and without self-reported walking difficulty.

Science.gov (United States)

Simonsick, E M; Guralnik, J M; Fried, L P

1999-06-01

To determine how severity of walking difficulty and sociodemographic, psychosocial, and health-related factors influence walking behavior in disabled older women. Cross-sectional analyses of baseline data from the Women's Health and Aging Study (WHAS). An urban community encompassing 12 contiguous zip code areas in the eastern portion of Baltimore City and part of Baltimore County, Maryland. A total of 920 moderately to severely disabled community-resident women, aged 65 years and older, identified from an age-stratified random sample of Medicare beneficiaries. Walking behavior was defined as minutes walked for exercise and total blocks walked per week. Independent variables included self-reported walking difficulty, sociodemographic factors, psychological status (depression, mastery, anxiety, and cognition), and health-related factors (falls and fear of falling, fatigue, vision and balance problems, weight, smoking, and cane use). Walking at least 8 blocks per week was strongly negatively related to severity of walking difficulty. Independent of difficulty level, older age, black race, fatigue, obesity, and cane use were also negatively associated with walking; living alone and high mastery had a positive association with walking. Even among functionally limited women, sociocultural, psychological, and health-related factors were independently associated with walking behavior. Thus, programs aimed at improving walking ability need to address these factors in addition to walking difficulties to maximize participation and compliance.

Analysis of difficulties in mathematics learning on students with guardian personality type in problem-solving HOTS geometry test

Science.gov (United States)

Karimah, R. K. N.; Kusmayadi, T. A.; Pramudya, I.

2018-04-01

Learning in the current 2013 curriculum is based on contextual issues based on questions that can encourage students to think broadly. HOTS is a real-life based assessment of everyday life, but in practice, the students are having trouble completing the HOTS issue. Learning difficulty is also influenced by personality type Based on the fact that the real difference one can see from a person is behavior. Kersey classifies the personality into 4 types, namely Idealist, Rational, Artisan, and Guardian. The researcher focuses on the type of guardian personality that is the type of personality that does not like the picture. This study aims to describe the difficulty of learning mathematics in students with a type of guardian personality in the completion of Geometry materials especially in solving HOTS. This research type is descriptive qualitative research. Instruments used in this study were the researchers themselves, personality class test sheets, learning difficulty test sheets in the form of HOTS Geometry test, and interview guides. The results showed that students with guardian personality it was found that a total of 3.37 % difficulties of number fact skill, 4.49 % difficulties of arithmetics skill, 37.08 % difficulties of information skill, 31.46% difficulties of language skill, 23.60 % difficulties of visual-spatial skill.

STRATEGIES OF COPING WITH DIFFICULTIES DURING RESEARCH PERFORMED BY YOUNG SCIENTISTS

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Tatiana G. Bokhan

2017-03-01

Full Text Available Introduction: young scientists engaged in creative activities face difficulties during scientific research, implementation and commercialisation of the results. The impossibility of coping with obstacles leads to the impairment of motivational and creative activity. The problem of studying the main semantic contents of difficult situations and strategies to cope with them becomes relevant as it is conducive to the process of personal development of young scientists. Materials and Methods: the authors used a questionnaire with open-ended questions for revealing the main difficulties and coping strategies in the process of research activity; COPE questionnaire adapted by E. Rasskazova, T. Gordeyeva, E. Osin; Style of Self-Regulation of Behaviour technique by V. I. Morosanova. Statistical data processing was carried out with descriptive statistics methods, analysis of frequencies, factor analysis (Varimax rotation with Kaiser normalisation, cluster analysis (furthest neighbour method and Ward’s method. Results: eight main semantic categories related to difficulties experienced in the process of performing the research work have been detected. The main ways of coping with arising difficulties have been identified. Types of respondents different in terms of coping strategies and regulatory-behavioural characteristics have been distinguished. Discussion and Conclusions: difficulties of self-organisation in time for realisation of new meanings, difficulties in structuring the research work and search for information act as psychological barriers provoking mental stress. The most efficient coping strategies in respondents are strategies Active coping and search for positive meaning and personal development. The inefficient coping strategy with difficulties complicating the process of self-development is Avoiding problems strategies.

The behaviour and self-esteem of children with specific speech and language difficulties.

Science.gov (United States)

Lindsay, G; Dockrell, J

2000-12-01

Children with specific speech and language difficulties (SSLD) may have associated difficulties that impair their access to the curriculum, and their social relationships at home and in school. (i) To identify the range of additional problems experienced by children with SSLD in different educational contexts; (ii) to consider the relationship between these problems and the child's current language status and (iii) to consider the child's self-esteem and the extent to which self-esteem is associated with the primary language problem or other associated difficulties. Sixty-nine children (17 girls, 52 boys) aged 7-8 years (Year 3) who had been identified as having SSLD, 59 from two local education authorities and 10 from regional special schools for children with severe speech and language difficulties. The children were assessed on a range of cognitive, language and educational measures; children and teachers completed a measure of the children's self-esteem (Pictorial Scale of Perceived Competence and Social Acceptance); teachers and parents completed a behavioural questionnaire (Strengths and Difficulties Questionnaire (SDQ); teachers also completed a further rating scale which included a behaviour subscale (Junior Rating Scale: JRS). The children's behaviour was rated as significantly different from the norm on both the SDQ and JRS, with the parents more likely to rate the child as having problems, but also as having prosocial behaviour. Both teachers and parents tended to rate the boys as having more problems than girls on the SDQ, with significant differences for the parents' ratings occurring on the total score and the hyperactivity and conduct problems scales. The children had positive self perceptions, which were comparable to the standardisation sample, and generally significantly higher than those of the teachers. The language and educational attainment scores of the children in special and mainstream schools were generally not significantly different, but

Exploring communication difficulties in pediatric hematology: oncology nurses.

Science.gov (United States)

Citak, Ebru Akgun; Toruner, Ebru Kilicarslan; Gunes, Nebahat Bora

2013-01-01

Communication plays an important role for the well being of patients, families and also health care professionals in cancer care. Conversely, ineffective communication may cause depression, increased anxiety, hopelessness and decreased of quality life for patients, families and also nurses. This study aimed to explore communication difficulties of pediatric hematology/oncology nurses with patients and their families, as well as their suggestions about communication difficulties. It was conducted in a pediatric hematology/oncology hospital in Ankara, Turkey. Qualitative data were collected by focus groups, with 21 pediatric hematology/oncology nursing staff from three groups. Content analysis was used for data analysis. Findings were grouped in three main categories. The first category concerned communication difficulties, assessing problems in responding to questions, ineffective communication and conflicts with the patient's families. The second was about the effects of communication difficulties on nurses and the last main category involved suggestions for empowering nurses with communication difficulties, the theme being related to institutional issues. Nurses experience communication difficulties with children and their families during long hospital stays. Communication difficulties particularly increase during crisis periods, like at the time of first diagnosis, relapse, the terminal stage or on days with special meaning such as holidays. The results obtained indicate that pediatric nurses and the child/family need to be supported, especially during crisis periods. Feeling of empowerment in communication will improve the quality of care by reducing the feelings of exhaustion and incompetence in nurses.

The factor structure of the Strengths and Difficulties Questionnaire (SDQ in Greek adolescents

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Rotsika Vasiliki

2009-08-01

Full Text Available Abstract Background The Strengths and Difficulties Questionnaire (SDQ is a practical, economic and user-friendly screening instrument of emotional and behavioural problems in children and adolescents. This study was aimed primarily at evaluating the factor structure of the Greek version of the SDQ. Methods A representative nationwide sample of 1,194 adolescents (11 to 17 years old completed the questionnaire. Confirmatory factor analysis (CFA was conducted to assess the factor structure of the SDQ. Results CFA supported the original five-factor structure. The modification of the model provided some improvements. Internal consistency was acceptable for total difficulties, emotional symptoms and prosocial behaviour scale, moderate for hyperactivity/inattention scale and inadequate for peer and conduct problems scale. Older adolescents (aged 15 to 17 years reported more hyperactivity/inattention and conduct problems than younger ones (aged 11 to 14 years and girls reported more emotional symptoms and less prosocial behaviour problems than boys. Adolescents of low socioeconomic status (SES reported more difficulties than those of medium and high SES. Conclusion The Greek SDQ could be potentially considered as a community-wide screening instrument for adolescents' emotional and behavioural problems.

Multiobjective Two-Stage Stochastic Programming Problems with Interval Discrete Random Variables

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S. K. Barik

2012-01-01

Full Text Available Most of the real-life decision-making problems have more than one conflicting and incommensurable objective functions. In this paper, we present a multiobjective two-stage stochastic linear programming problem considering some parameters of the linear constraints as interval type discrete random variables with known probability distribution. Randomness of the discrete intervals are considered for the model parameters. Further, the concepts of best optimum and worst optimum solution are analyzed in two-stage stochastic programming. To solve the stated problem, first we remove the randomness of the problem and formulate an equivalent deterministic linear programming model with multiobjective interval coefficients. Then the deterministic multiobjective model is solved using weighting method, where we apply the solution procedure of interval linear programming technique. We obtain the upper and lower bound of the objective function as the best and the worst value, respectively. It highlights the possible risk involved in the decision-making tool. A numerical example is presented to demonstrate the proposed solution procedure.

Difficulties in radiodiagnosis of children's tumors

International Nuclear Information System (INIS)

Kolinova, E.; Zitkova, M.; Suchmova, M.; Jirasek, M.

1984-01-01

Some problems of current radiodiagnosis in pediatric oncology are discussed. The main cause of errors in diagnosis and of difficulties barring timely correct diagnosis is the relatively small number of tumors in children and the ensuing lack of knowledge and experience in diagnosis. The situation can only be improved by the disciplined observance of purposeful diagnostic procedures and the centralization of these procedures at specialized departments. (author)

Psychosocial difficulties from the perspective of persons with neuropsychiatric disorders.

Science.gov (United States)

Coenen, Michaela; Cabello, Maria; Umlauf, Silvia; Ayuso-Mateos, José Luis; Anczewska, Marta; Tourunen, Jouni; Leonardi, Matilde; Cieza, Alarcos

2016-01-01

The objective of this study is to determine whether persons with neuropsychiatric disorders experience a common set of psychosocial difficulties using qualitative data from focus groups and individual interviews. The study was performed in five European countries (Finland, Italy, Germany, Poland and Spain) using the focus groups and individual interviews with persons with nine neuropsychiatric disorders (dementia, depression, epilepsy, migraine, multiple sclerosis, Parkinson's disease, schizophrenia, stroke and substance dependence). Digitally recorded sessions were analysed using a step-by-step qualitative and quantitative methodology resulting in the compilation of a common set of psychosocial difficulties using the International Classification of Functioning, Disability and Health (ICF) as a framework. Sixty-seven persons participated in the study. Most persons with neuropsychiatric disorders experience difficulties in emotional functions, sleeping, carrying out daily routine, working and interpersonal relationships in common. Sixteen out of 33 psychosocial difficulties made up the common set. This set includes mental functions, pain and issues addressing activities and participation and provides first evidence for the hypothesis of horizontal epidemiology of psychosocial difficulties in neuropsychiatric disorders. This study provides information about psychosocial difficulties that should be covered in the treatment and rehabilitation of persons with neuropsychiatric disorders regardless of clinical diagnoses. Emotional problems, work and sleep problems should be addressed in all the treatments of neuropsychiatric disorders regardless of their specific diagnosis, etiology and severity. Personality issues should be targeted in the treatment for neurological disorders, whereas communication skill training may also be useful for mental disorders. The effects of medication and social environment on patient's daily life should be considered in all the

A variable neighborhood descent based heuristic to solve the capacitated location-routing problem

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M. S. Jabal-Ameli

2011-01-01

Full Text Available Location-routing problem (LRP is established as a new research area in the context of location analysis. The primary concern of LRP is on locating facilities and routing of vehicles among established facilities and existing demand points. In this work, we address the capacitated LRP which arises in many practical applications within logistics and supply chain management. The objective is to minimize the overall system costs which include the fixed costs of opening depots and using vehicles at each depot site, and the variable costs associated with delivery activities. A novel heuristic is proposed which is based on variable neighborhood descent (VND algorithm to solve the resulted problem. The computational study indicates that the proposed VND based heuristic is highly competitive with the existing solution algorithms in terms of solution quality.

Upper-division student difficulties with the Dirac delta function

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Bethany R. Wilcox

2015-03-01

Full Text Available The Dirac delta function is a standard mathematical tool that appears repeatedly in the undergraduate physics curriculum in multiple topical areas including electrostatics, and quantum mechanics. While Dirac delta functions are often introduced in order to simplify a problem mathematically, students still struggle to manipulate and interpret them. To characterize student difficulties with the delta function at the upper-division level, we examined students’ responses to traditional exam questions and a standardized conceptual assessment, and conducted think-aloud interviews. Our analysis was guided by an analytical framework that focuses on how students activate, construct, execute, and reflect on the Dirac delta function in the context of problem solving in physics. Here, we focus on student difficulties using the delta function to express charge distributions in the context of junior-level electrostatics. Common challenges included invoking the delta function spontaneously, translating a description of a charge distribution into a mathematical expression using delta functions, integrating 3D or non-Cartesian delta function expressions, and recognizing that the delta function can have units. We also briefly discuss implications of these difficulties for instruction.

Subjective difficulties in young people related to extensive loud music listening

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Budimčić Milenko

2010-01-01

Full Text Available Introduction. For human ear, noise represents every undesirable and valueless sound. In disco clubs, as in some other places with loud music mostly attended by young people, the level of noise sometimes attains over 100 dB. As reported by numerous studies, a high noise level could induce subjective difficulties (ear buzzing, audition loss, vertigo and palpitations, anxiety, high blood pressure, decreased concentration, lowered memory storing. Objective. Assessment of subjective difficulties occurring in young people when staying in places with a high noise level (cafes, disco clubs, rock concerts, which can produce health problems, due to loud music, in association with demographic data, addictions and personal life style data. One of the goals is to find factors leading to subjective difficulties, which would be objectively studied in the second stage of the research and marked as early predictors of possible health problems. Methods. The study was conducted among 780 students of the Higher Healthcare School of Professional Studied in Belgrade. We used a questionnaire with 20 questions, divided into four categories: demographic data, case-history data, subjective problems and addictions of the subjects. In the statistical data processing we used the methods of descriptive and exploratory analysis, chi-square tests, correlation tests and Mantel-Haenszel odds ratio. Results. After listening loud music, 54.0% of examined subjects felt ear buzzing, and 4.6% had hearing damage. The habit of visiting places with loud music, mostly once a week in duration of 2-3 hours per visit had 80.4% of subjects. The presence of subjective complaints after listening of loud music was in association with loud music listening and disco clubs visits. The major reasons of the present subjective difficulties could be predicated by listening of loud music and club visits (r=0.918 and r=0.857. A relative risk for subjective difficulties presentation was 1.599. Conclusion

[Subjective difficulties in young people related to extensive loud music listening].

Science.gov (United States)

Budimcić, Milenko; Ignatović, Snezana; Zivić, Ljubica

2010-01-01

For human ear, noise represents every undesirable and valueless sound. In disco clubs, as in some other places with loud music mostly attended by young people, the level of noise sometimes attains over 100 dB. As reported by numerous studies, a high noise level could induce subjective difficulties (ear buzzing, audition loss, vertigo and palpitations, anxiety, high blood pressure, decreased concentration, lowered memory storing). Assessment of subjective difficulties occurring in young people when staying in places with a high noise level (cafes, disco clubs, rock concerts), which can produce health problems, due to loud music, in association with demographic data, addictions and personal life style data. One of the goals is to find factors leading to subjective difficulties, which would be objectively studied in the second stage of the research and marked as early predictors of possible health problems. The study was conducted among 780 students of the Higher Healthcare School of Professional Studied in Belgrade. We used a questionnaire with 20 questions, divided into four categories: demographic data, case-history data, subjective problems and addictions of the subjects. In the statistical data processing we used the methods of descriptive and exploratory analysis, chi-square tests, correlation tests and Mantel-Haenszel odds ratio. After listening loud music, 54.0% of examined subjects felt ear buzzing, and 4.6% had hearing damage. The habit of visiting places with loud music, mostly once a week in duration of 2-3 hours per visit had 80.4% of subjects. The presence of subjective complaints after listening of loud music was in association with loud music listening and disco clubs visits.The major reasons of the present subjective difficulties could be predicated by listening of loud music and club visits (r = 0.918 and r = 0.857). A relative risk for subjective difficulties presentation was 1.599. According to the results of our study, over half of children

Childhood maltreatment severity and alcohol use in adult psychiatric inpatients: The mediating role of emotion regulation difficulties.

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Dutcher, Christina D; Vujanovic, Anka A; Paulus, Daniel J; Bartlett, Brooke A

2017-09-01

Emotion regulation difficulties are a potentially key mechanism underlying the association between childhood maltreatment and alcohol use in adulthood. The current study examined the mediating role of emotion regulation difficulties in the association between childhood maltreatment severity (i.e., Childhood Trauma Questionnaire total score) and past-month alcohol use severity, including alcohol consumption frequency and alcohol-related problems (i.e., number of days of alcohol problems, ratings of "bother" caused by alcohol problems, ratings of treatment importance for alcohol problems). Participants included 111 acute-care psychiatric inpatients (45.0% female; Mage=33.5, SD=10.6), who reported at least one DSM-5 posttraumatic stress disorder Criterion A traumatic event, indexed via the Life Events Checklist for DSM-5. Participants completed questionnaires regarding childhood maltreatment, emotion regulation difficulties, and alcohol use. A significant indirect effect of childhood maltreatment severity via emotion regulation difficulties in relation to alcohol use severity (β=0.07, SE=0.04, 99% CI [0.01, 0.21]) was documented. Specifically, significant indirect effects were found for childhood maltreatment severity via emotion regulation difficulties in relation to alcohol problems (β's between 0.05 and 0.12; all 99% bootstrapped CIs with 10,000 resamples did not include 0) but not alcohol consumption. Emotion regulation difficulties may play a significant role in the association between childhood maltreatment severity and alcohol outcomes. Clinical implications are discussed. Copyright © 2017 Elsevier Inc. All rights reserved.

Workplace bullying and sleep difficulties: a 2-year follow-up study.

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Hansen, Ase Marie; Hogh, Annie; Garde, Anne Helene; Persson, Roger

2014-04-01

The aims of the present study were to investigate whether being subjected to bullying and witnessing bullying at the workplace was associated with concurrent sleep difficulties, whether frequently bullied/witnesses have more sleep difficulties than occasionally bullied/witnesses, and whether there were associations between being subjected to bullying or witnessing bullying at the workplace and subsequent sleep difficulties. A total of 3,382 respondents (67 % women and 33 % men) completed a baseline questionnaire about their psychosocial work environment and health. The overall response rate was 46 %. At follow-up 2 years later, 1671 of those responded to a second questionnaire (49 % of the 3,382 respondents at baseline). Sleep difficulties were measured in terms of disturbed sleep, awakening problems, and poor quality of sleep. Bullied persons and witnesses reported more sleep difficulties than those who were neither bullied nor witnesses to bullying at baseline. Frequently bullied/witnesses reported more sleep difficulties than respondents who were occasionally bullied or witnessing bullying at baseline. Further, odds ratios for subsequent sleep difficulties were increased among the occasionally bullied, but not among witnesses. However, the associations weakened when adjusting for sleep difficulties at baseline. Being subjected to occasional bullying at baseline was predictive of subsequent sleep difficulties. Witnessing bullying at baseline did not predict sleep difficulties at follow-up.

Problem solving: How can we help students overcome cognitive difficulties

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Liberato Cardellini

2014-12-01

Full Text Available The traditional approach to teach problem solving usually consists in showing students the solutions of some example-problems and then in asking students to practice individually on solving a certain number of related problems. This approach does not ensure that students learn to solve problems and above all to think about the solution process in a consistent manner. Topics such as atoms, molecules, and the mole concept are fundamental in chemistry and instructors may think that, for our students, should be easy to learn these concepts and to use them in solving problems, but it is not always so. If teachers do not put emphasis on the logical process during solving problems, students are at risk to become more proficient at applying the formulas rather than to reason. This disappointing result is clear from the outcomes of questionnaires meant to measure the ability to calculate the mass of a sample from the number of atoms and vice versa. A suggestion from the cognitive load theory has proved a useful way to improve students’ skills for this type of problems: the use of worked out examples. The repetition after two weeks of the Friedel-Maloney test after the use of worked examples shows that students' skills significantly improve. Successful students in all questions jumped from 2 to 64%.

Proband Mental Health Difficulties and Parental Stress Predict Mental Health in Toddlers at High-Risk for Autism Spectrum Disorders.

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Crea, Katherine; Dissanayake, Cheryl; Hudry, Kristelle

2016-10-01

Family-related predictors of mental health problems were investigated among 30 toddlers at familial high-risk for autism spectrum disorders (ASD) and 28 controls followed from age 2- to 3-years. Parents completed the self-report Depression Anxiety Stress Scales and the parent-report Behavior Assessment System for Children. High-risk toddlers were assessed for ASD at 3-years. Parent stress and proband mental health difficulties predicted concurrent toddler mental health difficulties at 2-years, but only baseline proband internalising problems continued to predict toddler internalising problems at 3-years; high-risk status did not confer additional risk. Baseline toddler mental health difficulties robustly predicted later difficulties, while high-risk status and diagnostic outcome conferred no additional risk. A family systems perspective may be useful for understanding toddler mental health difficulties.

IMPAIRED FERTILITY AND PERCEIVED DIFFICULTIES CONCEIVING IN GHANA: MEASUREMENT PROBLEMS AND PROSPECTS.

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Fledderjohann, Jasmine; Johnson, David R

2016-08-01

What is the most appropriate measure of impaired fertility for understanding its social consequences in sub-Saharan Africa? The dearth of subjective measures in surveys in the region has prevented comparisons of subjective and objective measures. Perceived difficulties conceiving may have a greater impact than objective measures for social outcomes such as divorce, stigmatization and distress. This study compares 12- (clinical) and 24- (epidemiological) month measures from biomedicine and 5- and 7-year measures from demography with a subjective measure of impaired fertility using correlations, random effects models and test-retest models to assess relationships between measures, their association with sociodemographic characteristics and the stability of measures across time. Secondary panel data (1998-2004) from 1350 Ghanaian women aged 15-49 of all marital statuses are used. Longer waiting times to identification of impaired fertility required by demographic measures result in more stable measures, but perceived difficulties conceiving are most closely aligned with clinical infertility (r=0.61; pconceiving and self-identified infertility to assess which is most valid; in order to accomplish this, it is imperative that subjective measures of infertility be included in social surveys in sub-Saharan Africa.

Problems of variance reduction in the simulation of random variables

International Nuclear Information System (INIS)

Lessi, O.

1987-01-01

The definition of the uniform linear generator is given and some of the mostly used tests to evaluate the uniformity and the independence of the obtained determinations are listed. The problem of calculating, through simulation, some moment W of a random variable function is taken into account. The Monte Carlo method enables the moment W to be estimated and the estimator variance to be obtained. Some techniques for the construction of other estimators of W with a reduced variance are introduced

Could Specific Braille Reading Difficulties Result from Developmental Dyslexia?

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Veispak, Anneli; Ghesquiere, Pol

2010-01-01

A proportion of children with visual impairments have specific reading difficulties that cannot be easily explained. This article reviews the data on problems with braille reading and interprets them from the framework of the temporal-processing deficit theory of developmental dyslexia.

Problem-solving skills of futsal players with regard to some socio-demographic variables

OpenAIRE

ACAR, Kürşat; CON, Musa; CANKAYA, Soner; TASMEKTEPLIGIL, Mehmet Yalcin

2017-01-01

The aim of this study is to evaluate problem-solving skills of female futsal teams that compete in the Futsal League of Turkish Universities Sports Federation in terms of some socio-demographic variables. In total, 144 students from female futsal teams of 10 universities competing in the Futsal League of Turkish Universities Sports Federation voluntarily took part in this study. In the study, “Problem-Solving Inventory” that was developed by Heppner & Petersen was used. With this inve...

Sociodemographic variables and social values: relationship with work-attendance problems in Brunei public- and private-sector employees

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Mundia, Lawrence; Mahalle, Salwa; Matzin, Rohani; Zakaria, Gamal Abdul Nasir; Abdullah, Nor Zaiham Midawati

2017-01-01

Objective The study investigated the degree to which selected sociodemographic variables and social values were related to work-attendance problems in a random sample of 860 Brunei public- and private-sector employees and the nature of this relationship. Materials and methods This quantitative study used the field-survey approach to administer research instruments directly to participants. This enabled the researchers to help participants who needed assistance in completing the measures properly, so as to increase the number of usable returns. Results Two sociodemographic variables (seeking help from a counselor/psychologist and marital status) correlated significantly with work attendance. Private-sector employees were more likely to have work-attendance problems than government workers. Both single and married employees and the chief wage earner in the household were more likely to have work-attendance issues to deal with compared to their counterparts. However, employees who sought help from a counselor/psychologist were far less likely to have work-attendance problems compared to those who did not get such help. The most significant social-value correlates with work-attendance problems were interpersonal communication, employer–employee relationship, work-stress problems, self-presentation, self-regulation, self-direction, and interpersonal trust. Self-regulation, self-direction, and satisfaction with work-related achievements significantly predicted work-attendance problems positively, while interpersonal communication problems and work-stress problems predicted work-attendance problems negatively. Low scorers on self-regulation and self-direction, as well as on satisfaction with work-related achievements, were more likely to have work-attendance problems compared to high scorers. However, low scorers on interpersonal communication and work-stress problems were less likely to have work-attendance problems compared to high-scoring peers. Conclusion Ample

Impaired fertility and perceived difficulties conceiving in Ghana : measurement problems and prospects

OpenAIRE

Fledderjohann, Jasmine; Johnson, David R.

2016-01-01

What is the most appropriate measure of impaired fertility for understanding its social consequences in sub-Saharan Africa? The dearth of subjective measures in surveys in the region has prevented comparisons of subjective and objective measures. Perceived difficulties conceiving may have a greater impact than objective measures for social outcomes such as divorce, stigmatization and distress. This study compares 12- (clinical) and 24- (epidemiological) month measures from biomedicine and 5- ...

BASIC SUPPOSITIONS FOR ORGANIZING AND ESTABLISHING A COHERENT SYSTEM OF EARLY TREATMENT AND PRE-SCHOOL UPBRINGING OF CHILDREN WITH DEVELOPMENTAL DIFFICULTIES IN CONDITIONS OF TRANSITION (situation, problems and needs

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Ljupco Ajdinski

1997-03-01

Full Text Available The author of this paper wants to pay attention to the utmost problems of treatment and pre-school upbringing, from several points of view ( health, social, educational, economic, normative etc., that are related to the establishment of the primary conditions and suppositions for successful organization of protection and rehabilitation of these children.Children with developmental difficulties are quite a complex problem of the family, society and professional problem. The complexity and the burden of this problem are seen through the type and level of impairment, through the number of such children, as in providing financial, personnel and other conditions that are needed for successful protection and treatment.Taking into consideration the number of these children, in the paper is given the prognosis according to some percentages used for the whole population by ON and WHO. It is considered that 5-7 % are children with developmental difficulties at pre-school period. because the main topic at this Symposium is early treatment and pre- school upbringing, the early age is taken for the mentioned percentage. According to this, in our country there are about 19.000 children from 0-9 years of age, if this percentage of 6 % is applied from the total number of children at that age, that shows in the latest census of the population in the R. of Macedonia in 1994 , that there are 313.908 children. This number shows the gravity of the problem that is elaborated in this paper. The author stresses that the complexity of this problem increases if we take into consideration the present conditions according to the range of these children with early treatment and preschool upbringing, as apart of the whole system of rehabilitation.The complete treatment, i.e. the rehabilitation of children with developmental difficulties presents the unity of all the provisions and proceedings that are necessary to be undertaken to eliminate or reduce to the minimum

Gender differences in the pathway from adverse life events to adolescent emotional and behavioural problems via negative cognitive errors.

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Flouri, Eirini; Panourgia, Constantina

2011-06-01

The aim of this study was to test for gender differences in how negative cognitive errors (overgeneralizing, catastrophizing, selective abstraction, and personalizing) mediate the association between adverse life events and adolescents' emotional and behavioural problems (measured with the Strengths and Difficulties Questionnaire). The sample consisted of 202 boys and 227 girls (aged 11-15 years) from three state secondary schools in disadvantaged areas in one county in the South East of England. Control variables were age, ethnicity, special educational needs, exclusion history, family structure, family socio-economic disadvantage, and verbal cognitive ability. Adverse life events were measured with Tiet et al.'s (1998) Adverse Life Events Scale. For both genders, we assumed a pathway from adverse life events to emotional and behavioural problems via cognitive errors. We found no gender differences in life adversity, cognitive errors, total difficulties, peer problems, or hyperactivity. In both boys and girls, even after adjustment for controls, cognitive errors were related to total difficulties and emotional symptoms, and life adversity was related to total difficulties and conduct problems. The life adversity/conduct problems association was not explained by negative cognitive errors in either gender. However, we found gender differences in how adversity and cognitive errors produced hyperactivity and internalizing problems. In particular, life adversity was not related, after adjustment for controls, to hyperactivity in girls and to peer problems and emotional symptoms in boys. Cognitive errors fully mediated the effect of life adversity on hyperactivity in boys and on peer and emotional problems in girls.

Continuous-Variable Quantum Computation of Oracle Decision Problems

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Adcock, Mark R. A.

Quantum information processing is appealing due its ability to solve certain problems quantitatively faster than classical information processing. Most quantum algorithms have been studied in discretely parameterized systems, but many quantum systems are continuously parameterized. The field of quantum optics in particular has sophisticated techniques for manipulating continuously parameterized quantum states of light, but the lack of a code-state formalism has hindered the study of quantum algorithms in these systems. To address this situation, a code-state formalism for the solution of oracle decision problems in continuously-parameterized quantum systems is developed. Quantum information processing is appealing due its ability to solve certain problems quantitatively faster than classical information processing. Most quantum algorithms have been studied in discretely parameterized systems, but many quantum systems are continuously parameterized. The field of quantum optics in particular has sophisticated techniques for manipulating continuously parameterized quantum states of light, but the lack of a code-state formalism has hindered the study of quantum algorithms in these systems. To address this situation, a code-state formalism for the solution of oracle decision problems in continuously-parameterized quantum systems is developed. In the infinite-dimensional case, we study continuous-variable quantum algorithms for the solution of the Deutsch--Jozsa oracle decision problem implemented within a single harmonic-oscillator. Orthogonal states are used as the computational bases, and we show that, contrary to a previous claim in the literature, this implementation of quantum information processing has limitations due to a position-momentum trade-off of the Fourier transform. We further demonstrate that orthogonal encoding bases are not unique, and using the coherent states of the harmonic oscillator as the computational bases, our formalism enables quantifying

Simulating the Cost of Cooperation: A Recipe for Collaborative Problem-Solving

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Andrea Guazzini

2018-06-01

Full Text Available Collective problem-solving and decision-making, along with other forms of collaboration online, are central phenomena within ICT. There had been several attempts to create a system able to go beyond the passive accumulation of data. However, those systems often neglect important variables such as group size, the difficulty of the tasks, the tendency to cooperate, and the presence of selfish individuals (free riders. Given the complex relations among those variables, numerical simulations could be the ideal tool to explore such relationships. We take into account the cost of cooperation in collaborative problem solving by employing several simulated scenarios. The role of two parameters was explored: the capacity, the group’s capability to solve increasingly challenging tasks coupled with the collective knowledge of a group, and the payoff, an individual’s own benefit in terms of new knowledge acquired. The final cooperation rate is only affected by the cost of cooperation in the case of simple tasks and small communities. In contrast, the fitness of the community, the difficulty of the task, and the groups sizes interact in a non-trivial way, hence shedding some light on how to improve crowdsourcing when the cost of cooperation is high.

Variables separation and superintegrability of the nine-dimensional MICZ-Kepler problem

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Phan, Ngoc-Hung; Le, Dai-Nam; Thoi, Tuan-Quoc N.; Le, Van-Hoang

2018-03-01

The nine-dimensional MICZ-Kepler problem is of recent interest. This is a system describing a charged particle moving in the Coulomb field plus the field of a SO(8) monopole in a nine-dimensional space. Interestingly, this problem is equivalent to a 16-dimensional harmonic oscillator via the Hurwitz transformation. In the present paper, we report on the multiseparability, a common property of superintegrable systems, and the superintegrability of the problem. First, we show the solvability of the Schrödinger equation of the problem by the variables separation method in different coordinates. Second, based on the SO(10) symmetry algebra of the system, we construct explicitly a set of seventeen invariant operators, which are all in the second order of the momentum components, satisfying the condition of superintegrability. The found number 17 coincides with the prediction of (2n - 1) law of maximal superintegrability order in the case n = 9. Until now, this law is accepted to apply only to scalar Hamiltonian eigenvalue equations in n-dimensional space; therefore, our results can be treated as evidence that this definition of superintegrability may also apply to some vector equations such as the Schrödinger equation for the nine-dimensional MICZ-Kepler problem.

Economic Difficulty and Coping Strategies of Low Income Faculty Members as Related to their Teaching Performance

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Ronaldo F. Frufonga

2015-11-01

Full Text Available This study ascertained the relationship between difficulties and coping strategies as related to teaching performance of West Visayas State University-Janiuay Campus (WVSU-JC faculty for the School Year 2014-2015. The survey-correlational method was used with teaching performance as dependent variables, experienced economic difficulties as the independent variable, and coping strategy as moderator variable. The participants in the study were the 52 faculty who were selected through purposive sampling. Data were gathered through a researcher-made questionnaire-checklist and Faculty Performance Evaluation System. The statistical tools used were frequency count, rank, mean, standard deviation, and Pearson's Product-Moment Coefficient of Correlation. All statistical computations were availed of through the Statistical Package for the Social Sciences (SPSS software. Results revealed that the top economic difficulty experienced by faculty was limited cash. The topmost coping strategy employed by faculty was buying only basic foods or things for household. The faculty also experienced economic difficulty to a “moderate extent.” Nevertheless, the performance of the faculty was found to be “outstanding.” Teachers were affected by such financial crisis. However, despite their experienced economic difficulties, as major agents for change, they performed their best for the improvement of quality education. No significant relationships existed between coping strategies and teaching performance of faculty.

Modified strip packing heuristics for the rectangular variable-sized bin packing problem

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FG Ortmann

2010-06-01

Full Text Available Two packing problems are considered in this paper, namely the well-known strip packing problem (SPP and the variable-sized bin packing problem (VSBPP. A total of 252 strip packing heuristics (and variations thereof from the literature, as well as novel heuristics proposed by the authors, are compared statistically by means of 1170 SPP benchmark instances in order to identify the best heuristics in various classes. A combination of new heuristics with a new sorting method yields the best results. These heuristics are combined with a previous heuristic for the VSBPP by the authors to find good feasible solutions to 1357 VSBPP benchmark instances. This is the largest statistical comparison of algorithms for the SPP and the VSBPP to the best knowledge of the authors.

Exhaustive Search for Sparse Variable Selection in Linear Regression

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Igarashi, Yasuhiko; Takenaka, Hikaru; Nakanishi-Ohno, Yoshinori; Uemura, Makoto; Ikeda, Shiro; Okada, Masato

2018-04-01

We propose a K-sparse exhaustive search (ES-K) method and a K-sparse approximate exhaustive search method (AES-K) for selecting variables in linear regression. With these methods, K-sparse combinations of variables are tested exhaustively assuming that the optimal combination of explanatory variables is K-sparse. By collecting the results of exhaustively computing ES-K, various approximate methods for selecting sparse variables can be summarized as density of states. With this density of states, we can compare different methods for selecting sparse variables such as relaxation and sampling. For large problems where the combinatorial explosion of explanatory variables is crucial, the AES-K method enables density of states to be effectively reconstructed by using the replica-exchange Monte Carlo method and the multiple histogram method. Applying the ES-K and AES-K methods to type Ia supernova data, we confirmed the conventional understanding in astronomy when an appropriate K is given beforehand. However, we found the difficulty to determine K from the data. Using virtual measurement and analysis, we argue that this is caused by data shortage.

Adolescents’ Problem Behaviors and Parent-Adolescent Conflicts in Hmong Immigrant Families

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Zha Blong Xiong

2009-01-01

Full Text Available The purpose of the study was to investigate whether Hmong adolescent problem behaviors and school difficulties influence parent-adolescent conflicts above and beyond the variables of adolescents’ embarrassment about their parents, the acculturation gap between parents and adolescents, and age of adolescents. The sample included 209 Hmong adolescents living in Minnesota. There were 123 males and 86 females, ages 12 to 25 years. A survey was administered in several community agencies to adolescents that included their perspectives on the frequency and intensity of parent-adolescent disagreements on 28 issues and the problem behaviors of delinquent peer affiliation, gang involvement, truancy, and school performance. Results of hierarchical multiple regression analyses indicated the set of problem-behavior independent variables explained 26% of the variance in the frequency-intensity of father-adolescent conflicts and 21% of the variance in the frequency-intensity of mother-adolescent conflicts. Ideas for parent education in the Hmong community are discussed.

Mental health problems in adolescents with cochlear implants: Peer problems persist after controlling for additional handicaps

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Maria eHuber

2015-07-01

Full Text Available The aims of the present multi-center study were to investigate the extent of mental health problems in adolescents with a hearing loss and cochlear implants (CIs in comparison to normal hearing (NH peers and to investigate possible relations between the extent of mental health problems of young CI users and hearing variables, such as age at implantation, or functional gain of CI. The survey included 140 adolescents with CI (mean age = 14.7, SD = 1.5 years and 140 NH adolescents (mean age = 14.8, SD = 1.4 years, their parents and teachers. Participants were matched by age, gender and social background. Within the CI group, 35 adolescents were identified as risk cases due to possible and manifest additional handicaps, and 11 adolescents were non-classifiable. Mental health problems were assessed with the Strengths and Difficulties Questionnaire (SDQ in the versions Self, Parent, and Teacher. The CI group showed significantly more Peer Problems than the NH group. When the CI group was split into a risk-group (35 risk cases and 11 non-classifiable persons and a non-risk group (n = 94, increased peer problems were perceived in both CI subgroups by adolescents themselves. However, no further differences between the CI non-risk group and the NH group were observed in any rater. The CI-risk group showed significantly more hyperactivity compared to the NH group and more hyperactivity and conduct problems compared to the CI non-risk group. Cluster analyses confirmed that there were significantly more adolescents with high problems in the CI-risk group compared to the CI non-risk group and the NH group. Adolescents with CI, who were able to understand speech in noise had significantly less difficulties compared to constricted CI users. Parents, teachers, and clinicians should be aware that CI users with additionally special needs may have mental health problems. However, peer problems were also experienced by CI adolescents without additional handicaps

Prevalence of Persistent Primary Reflexes and Motor Problems in Children with Reading Difficulties

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McPhillips, M.; Sheehy, N.

2004-01-01

It has been shown that some children with reading difficulties have underlying developmental delay and that this may be related to the persistence of primary reflexes. This study investigated the prevalence of persistent primary reflexes in the ordinary primary school population and how this related to other cognitive and social factors. Three…

TWO-DIMENSIONAL APPROXIMATION OF EIGENVALUE PROBLEMS IN SHELL THEORY: FLEXURAL SHELLS

Institute of Scientific and Technical Information of China (English)

无

2000-01-01

The eigenvalue problem for a thin linearly elastic shell, of thickness 2e, clamped along its lateral surface is considered. Under the geometric assumption on the middle surface of the shell that the space of inextensional displacements is non-trivial, the authors obtain, as ε→0,the eigenvalue problem for the two-dimensional"flexural shell"model if the dimension of the space is infinite. If the space is finite dimensional, the limits of the eigenvalues could belong to the spectra of both flexural and membrane shells. The method consists of rescaling the variables and studying the problem over a fixed domain. The principal difficulty lies in obtaining suitable a priori estimates for the scaled eigenvalues.

A population-based investigation into the self-reported reasons for sleep problems.

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David Armstrong

Full Text Available Typologies of sleep problems have usually relied on identifying underlying causes or symptom clusters. In this study the value of using the patient's own reasons for sleep disturbance are explored. Using secondary data analysis of a nationally representative psychiatric survey the patterning of the various reasons respondents provided for self-reported sleep problems were examined. Over two thirds (69.3% of respondents could identify a specific reason for their sleep problem with worry (37.9% and illness (20.1% representing the most commonly reported reasons. And while women reported more sleep problems for almost every reason compared with men, the patterning of reasons by age showed marked variability. Sleep problem symptoms such as difficulty getting to sleep or waking early also showed variability by different reasons as did the association with major correlates such as worry, depression, anxiety and poor health. While prevalence surveys of 'insomnia' or 'poor sleep' often assume the identification of an underlying homogeneous construct there may be grounds for recognising the existence of different sleep problem types particularly in the context of the patient's perceived reason for the problem.

The effects of task difficulty, novelty and the size of the search space on intrinsically motivated exploration.

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Baranes, Adrien F; Oudeyer, Pierre-Yves; Gottlieb, Jacqueline

2014-01-01

Devising efficient strategies for exploration in large open-ended spaces is one of the most difficult computational problems of intelligent organisms. Because the available rewards are ambiguous or unknown during the exploratory phase, subjects must act in intrinsically motivated fashion. However, a vast majority of behavioral and neural studies to date have focused on decision making in reward-based tasks, and the rules guiding intrinsically motivated exploration remain largely unknown. To examine this question we developed a paradigm for systematically testing the choices of human observers in a free play context. Adult subjects played a series of short computer games of variable difficulty, and freely choose which game they wished to sample without external guidance or physical rewards. Subjects performed the task in three distinct conditions where they sampled from a small or a large choice set (7 vs. 64 possible levels of difficulty), and where they did or did not have the possibility to sample new games at a constant level of difficulty. We show that despite the absence of external constraints, the subjects spontaneously adopted a structured exploration strategy whereby they (1) started with easier games and progressed to more difficult games, (2) sampled the entire choice set including extremely difficult games that could not be learnt, (3) repeated moderately and high difficulty games much more frequently than was predicted by chance, and (4) had higher repetition rates and chose higher speeds if they could generate new sequences at a constant level of difficulty. The results suggest that intrinsically motivated exploration is shaped by several factors including task difficulty, novelty and the size of the choice set, and these come into play to serve two internal goals-maximize the subjects' knowledge of the available tasks (exploring the limits of the task set), and maximize their competence (performance and skills) across the task set.

The effects of task difficulty, novelty and the size of the search space on intrinsically motivated exploration

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Adrien Fredj Baranes

2014-10-01

Full Text Available Devising efficient strategies for exploration in large open-ended spaces is one of the most difficult computational problems of intelligent organisms. Because the available rewards are ambiguous or unknown during the exploratory phase, subjects must act in intrinsically motivated fashion. However, a vast majority of behavioral and neural studies to date have focused on decision making in reward-based tasks, and the rules guiding intrinsically motivated exploration remain largely unknown. To examine this question we developed a paradigm for systematically testing the choices of human observers in a free play context. Adult subjects played a series of short computer games of variable difficulty, and freely choose which game they wished to sample without external guidance or physical rewards. Subjects performed the task in three distinct conditions where they sampled from a small or a large choice set (7 vs 64 possible levels of difficulty, and where they did or did not have the possibility to sample new games at a constant level of difficulty. We show that despite the absence of external constraints, the subjects spontaneously adopted a structured exploration strategy whereby they (1 started with easier games and progressed to more difficult games, (2 sampled the entire choice set including extremely difficult games that could not be learnt, (3 repeated moderately and high difficulty games much more frequently than was predicted by chance, and (4 had higher repetition rates and chose higher speeds if they could generate new sequences at a constant level of difficulty. The results suggest that intrinsically motivated exploration is shaped by several factors including task difficulty, novelty and the size of the choice set, and these come into play to serve two internal goals - maximize the subjects’ knowledge of the available tasks (exploring the limits of the task set, and maximize their competence (performance and skills across the task set.

Scaffolding for solving problem in static fluid: A case study

Science.gov (United States)

Koes-H, Supriyono; Muhardjito, Wijaya, Charisma P.

2018-01-01

Problem solving is one of the basic abilities that should be developed from learning physics. However, students still face difficulties in the process of non-routine problem-solving. Efforts are necessary to be taken in order to identify such difficulties and the solutions to solve them. An effort in the form of a diagnosis of students' performance in problem solving can be taken to identify their difficulties, and various instructional scaffolding supports can be utilized to eliminate the difficulties. This case study aimed to describe the students' difficulties in solving static fluid problems and the effort to overcome such difficulties through different scaffolding supports. The research subjects consisted of four 10-grade students of (Public Senior High School) SMAN 4 Malang selected by purposive sampling technique. The data of students' difficulties were collected via think-aloud protocol implemented on students' performance in solving non-routine static fluid problems. Subsequently, combined scaffolding supports were given to the students based on their particular difficulties. The research findings pointed out that there were several conceptual difficulties discovered from the students when solving static fluid problems, i.e. the use of buoyancy force formula, determination of all forces acting on a plane in a fluid, the resultant force on a plane in a fluid, and determination of a plane depth in a fluid. An effort that can be taken to overcome such conceptual difficulties is providing a combination of some appropriate scaffolding supports, namely question prompts with specific domains, simulation, and parallel modeling. The combination can solve students' lack of knowledge and improve their conceptual understanding, as well as help them to find solutions by linking the problems with their prior knowledge. According to the findings, teachers are suggested to diagnose the students' difficulties so that they can provide an appropriate combination of

A class of constitutive relations with internal variable derivatives: derivation from homogenization and initial value problem

International Nuclear Information System (INIS)

Andrieux, S.; Joussemet, M.; Lorentz, E.

1996-01-01

When they are subjected to excessive loads, some materials may exhibit a softening behaviour resulting from the deterioration of their mechanical properties. To idealize such behaviours, constitutive relations with softening are introduced, for which the size of the domain of reversibility in the stress-space decreases. These models feature a strain localization within the material, in agreement with experiments, but cannot predict the subsequent behaviour because they lead to shear bands the width of which is equal to zero, physically unacceptable and numerically troublesome. It has been proposed in the literature to overcome these difficulties by adding to the list of internal variable the spatial gradients of some of them. This procedure suffers from lack of firm methodological basis. Although, some quantitative justification have been advanced relying on some kind of microscopic analysis. Therefore, we propose to extend the classical (local) models by introducing the internal state variable first gradients. Given local model within the framework of standard generalized materials, consistent homogenization procedure is put forward to derive macroscopic free energy and dissipation potentials. The standard generalized character is preserved, with an extended set of state variables, containing not only the strain and the internal variables but also the internal variable derivatives. Nevertheless, when dealing with the whole structure, the independence between the new state variables is lost. We propose then to generalize the constitutive relations, leading to a new variational principle that ensures the Clausius-Duhem inequality at the structure scale. (authors)

Motor and Coordination Difficulties in Children with Emotional and Behavioural Difficulties

Science.gov (United States)

Hill, Elisabeth; Pratt, Michelle L; Kanji, Zara; Bartoli, Alice Jones

2017-01-01

To date, very few studies have explored the incidence of motor impairment amongst children with social, emotional and behavioural difficulties (social, emotional and mental health (SEMH); formerly SEBD in England). Following research that suggests an increase in motor difficulties in young children and adolescents with SEMH difficulties, this…

Analysis of potential dynamic concealed factors in the difficulty of lower third molar extraction.

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Singh, P; Ajmera, D-H; Xiao, S-S; Yang, X-Z; Liu, X; Peng, B

2016-11-01

The purpose of this study was to identify potential concealed variables associated with the difficulty of lower third molar (M3) extractions. To address the research purpose, we implemented a prospective study and enrolled a sample of subjects presenting for M3 removal. Predictor variables were categorized into Group-I and Group-II, based on predetermined criteria. The primary outcome variable was the difficulty of extraction, measured as extraction time. Appropriate univariate and multivariate statistics were computed using ordinal logistic regression. The sample comprised of 1235 subjects with a mean age of 29.49 +/- 8.92 years in Group-I and 26.20 +/- 11.55 years in Group-II subjects. The mean operating time per M3 extraction was 21.24 +/- 12.80 and 20.24 +/- 12.50 minutes for Group-I and Group-II subjects respectively. Three linear parameters including B-M2 height (distance between imaginary point B on the inferior border of mandibular body, and M2), lingual cortical thickness, bone density and one angular parameter including Rc-Cs angle (angle between ramus curvature and curve of spee), in addition to patient's age, profile type, facial type, cant of occlusal plane, and decreased overbite, were found to be statistically associated ( p < or = 0.05) with extraction difficulty under regression models. In conclusion, our study indicates that the difficulty of lower M3 extractions is possibly governed by morphological and biomechanical factors with substantial influence of myofunctional factors. Preoperative evaluation of dynamic concealed factors may not only help in envisaging the difficulty and planning of surgical approach but might also help in better time management in clinical practice.

Sickness certification difficulties in Ireland--a GP focus group study.

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Foley, M; Thorley, K; Von Hout, M-C

2013-07-01

Sickness certification causes problems for general practitioners (GPs). Difficulty with the assessment of capacity to work, conflict with patients and other non-medical factors have been shown to influence GPs' decision-making. Inadequate leadership and management of certification issues add to GPs' difficulties. To explore problems associated with sickness certification, as part of a larger mixed method research project exploring GPs' experiences and perceptions of sickness certification in Ireland. A qualitative study in an urban region of Ireland. A focus group of four male and four female GPs explored problems encountered by GPs in certifying sickness absence. Thematic data analysis was used. Three major themes emerged: perception of the sickness certification system, organization of health care and cultural factors in sickness absence behaviour. Employment structures in public and private sectors and lack of communication with other health care providers and employers were identified as complicating sickness certification. GPs encounter a complexity of issues in sick certification and are dissatisfied with their role in certifying sickness absence. Our results open the debate for policy change and development in Ireland.

Associations between sports participation and psychological difficulties during childhood: a two-year follow up.

Science.gov (United States)

Vella, Stewart A; Cliff, Dylan P; Magee, Christopher A; Okely, Anthony D

2015-05-01

This paper assessed the associations between sports participation and the development of psychological strengths and difficulties during childhood. Two-year follow up study of a sample of 4042 Australian children who were followed from age 8 years to 10 years. Parents reported children's participation in organised sports, and completed the Strengths and Difficulties Questionnaire. Univariate general linear models were used to examine the association between changes in sports participation and psychological strengths and difficulties at 10 years, adjusting for psychological strengths and difficulties at age 8. Children who maintained participation in sport had lower rates of parent-reported psychological difficulties at 10 years compared with children who dropped out of sport. Less internalising problems were also reported for children who participated in organised sports compared to children who dropped out of sports and children who did not participate in sports. These relationships did not differ by BMI, socioeconomic status, or parental education. Greater psychological difficulties are experienced by children who drop out of sports, and greater social and emotional problems are experienced by children who drop out of sports and who do not participate in organised sports. Due consideration should be given to the quality and implementation of sporting programs to ensure that they provide benefits to mental health. Due consideration should also be given to the potential psychological difficulties being experienced by children who drop out of organised sports as a higher level of psychological difficulties may be experienced prior to or subsequent to dropout. Copyright © 2014 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Variable sleep schedules and outcomes in children with psychopathological problems: preliminary observations

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Spruyt K

2012-02-01

Full Text Available Karen Spruyt1, Danielle L Raubuck2, Katie Grogan2, David Gozal1, Mark A Stein21Department of Pediatrics and Comer Children’s Hospital, Pritzker School of Medicine, University of Chicago, Chicago, IL; 2Institute for Juvenile Research, Hyperactivity and Learning Problems Clinic, University of Illinois at Chicago, Chicago, ILBackground: Night-to-night variability in sleep of children with attention deficit hyperactivity disorder (ADHD may be a mediator of behavioral phenotype. We examined the potential association between alertness, sleep, and eating behaviors in children with ADHD and comorbid problems.Methods: Sleep was monitored by actigraphy for 7 days. Questionnaires were used to assess sleep complaints, habits and food patterns by parental report, and sleep complaints and sleepiness by child report.Results: The group comprised 18 children, including 15 boys, aged 9.4 ± 1.7 years, 88.9% Caucasian, who took one or multiple medications. Children slept on average for 6 hours and 58 minutes with a variability of 1 hour 3 minutes relative to the mean, and their sleepiness scores were highly variable from day to day. Most children had a normal body mass index (BMI. Sleepiness and BMI were associated with sleep schedules and food patterns, such that they accounted for 76% of variance, predominantly by the association of BMI with mean wake after sleep onset and by bedtime sleepiness, with wake after sleep onset variability. Similarly, 97% of variance was shared with eating behaviors, such as desserts and snacks, and fast food meals were associated with morning sleepiness.Conclusion: Disrupted sleep and sleepiness appears to favor unhealthy food patterns and may place children with ADHD at increased risk for obesity.Keywords: sleep, child, attention deficit hyperactivity disorder, actigraphy

Working Memory Deficits in Children with Reading Difficulties: Memory Span and Dual Task Coordination

Science.gov (United States)

Wang, Shinmin; Gathercole, Susan E.

2013-01-01

The current study investigated the cause of the reported problems in working memory in children with reading difficulties. Verbal and visuospatial simple and complex span tasks, and digit span and reaction times tasks performed singly and in combination, were administered to 46 children with single word reading difficulties and 45 typically…

Review of student difficulties in upper-level quantum mechanics

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Chandralekha Singh

2015-09-01

Full Text Available [This paper is part of the Focused Collection on Upper Division Physics Courses.] Learning advanced physics, in general, is challenging not only due to the increased mathematical sophistication but also because one must continue to build on all of the prior knowledge acquired at the introductory and intermediate levels. In addition, learning quantum mechanics can be especially challenging because the paradigms of classical mechanics and quantum mechanics are very different. Here, we review research on student reasoning difficulties in learning upper-level quantum mechanics and research on students’ problem-solving and metacognitive skills in these courses. Some of these studies were multiuniversity investigations. The investigations suggest that there is large diversity in student performance in upper-level quantum mechanics regardless of the university, textbook, or instructor, and many students in these courses have not acquired a functional understanding of the fundamental concepts. The nature of reasoning difficulties in learning quantum mechanics is analogous to reasoning difficulties found via research in introductory physics courses. The reasoning difficulties were often due to overgeneralizations of concepts learned in one context to another context where they are not directly applicable. Reasoning difficulties in distinguishing between closely related concepts and in making sense of the formalism of quantum mechanics were common. We conclude with a brief summary of the research-based approaches that take advantage of research on student difficulties in order to improve teaching and learning of quantum mechanics.

Stress and suicidal ideation among adolescents having academic difficulty

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Priti Arun

2017-01-01

Full Text Available Background and Objectives: Academically typically achieving adolescents were compared with students having academic difficulty on stress and suicidal ideas. Materials and Methods: In a cross-sectional study, 75 academically typically achieving adolescents were compared with 105 students with academic difficulty and 52 students with specific learning disability (SLD. Academic functioning was assessed using teacher's screening instrument, intelligence quotient, and National Institute of Mental Health and Neurosciences index for SLD. Stress and suicidal ideas were assessed using general health questionnaire, suicide risk-11, and Mooney Problem Checklist (MPC. Appropriate statistical methods were applied. Results: Three groups were comparable on age, gender, mother's working status, being only child, nuclear family, self-reported academic decline, and type of school. About half of adolescents reported psychological problems on General Health Questionnaire (mean score >3 in all the groups. Academically typically achieving adolescents showed higher stressors in peer relationships, planning for future and suicidal ideation compared to adolescents with academic difficulty. Adolescents face stress regarding worry about examinations, family not understanding what child has to do in school, unfair tests, too much work in some subjects, afraid of failure in school work, not spending enough time in studies, parental expectations, wanting to be more popular, worried about a family member, planning for the future, and fear of the future. Significant positive correlation was seen between General Health Questionnaire scores and all four subscales of MPC. Suicidal ideas showed a negative correlation with MPC. Interpretations and Conclusions: Adolescents experience considerable stress in multiple areas irrespective of their academic ability and performance. Hence, assessment and management of stress among adolescents must extend beyond academic difficulties.

Masculine Discrepancy Stress, Emotion-Regulation Difficulties, and Intimate Partner Violence.

Science.gov (United States)

Berke, Danielle S; Reidy, Dennis E; Gentile, Brittany; Zeichner, Amos

2016-05-24

Research suggests that masculine socialization processes contribute to the perpetration of intimate partner violence (IPV) by men. Although this research has traditionally focused on men who strongly adhere to traditional gender norms, men who negatively evaluate themselves as falling short of these norms (a construct termed masculine discrepancy stress) have proven to be at increased risk of IPV perpetration. Likewise, men experiencing problems with emotion regulation, a multidimensional construct reflecting difficulties in effectively experiencing and responding to emotional states, are also at risk of IPV perpetration. In the present research, we tested the hypothesis that the link between discrepancy stress and IPV perpetration is mediated via difficulties in emotion regulation. Three hundred fifty-seven men completed online surveys assessing their experience of discrepancy stress, emotion-regulation difficulties, and history of IPV perpetration. Results indicated that discrepancy-stressed men's use of physical IPV was fully mediated by emotion-regulation difficulties. In addition, emotion-regulation difficulties partially mediated the association between discrepancy stress and sexual IPV. Findings are discussed in terms of the potential utility of emotion-focused interventions for modifying men's experience and expression of discrepancy stress and reducing perpetration of IPV. © The Author(s) 2016.

Masculine Discrepancy Stress, Emotion-Regulation Difficulties, and Intimate Partner Violence

Science.gov (United States)

Berke, Danielle S.; Reidy, Dennis E.; Gentile, Brittany; Zeichner, Amos

2018-01-01

Research suggests that masculine socialization processes contribute to the perpetration of intimate partner violence (IPV) by men. Although this research has traditionally focused on men who strongly adhere to traditional gender norms, men who negatively evaluate themselves as falling short of these norms (a construct termed masculine discrepancy stress) have proven to be at increased risk of IPV perpetration. Likewise, men experiencing problems with emotion regulation, a multidimensional construct reflecting difficulties in effectively experiencing and responding to emotional states, are also at risk of IPV perpetration. In the present research, we tested the hypothesis that the link between discrepancy stress and IPV perpetration is mediated via difficulties in emotion regulation. Three hundred fifty-seven men completed online surveys assessing their experience of discrepancy stress, emotion-regulation difficulties, and history of IPV perpetration. Results indicated that discrepancy-stressed men's use of physical IPV was fully mediated by emotion-regulation difficulties. In addition, emotion-regulation difficulties partially mediated the association between discrepancy stress and sexual IPV. Findings are discussed in terms of the potential utility of emotion-focused interventions for modifying men's experience and expression of discrepancy stress and reducing perpetration of IPV. PMID:27226013

Flexibility in Mathematics Problem Solving Based on Adversity Quotient

Science.gov (United States)

Dina, N. A.; Amin, S. M.; Masriyah

2018-01-01

Flexibility is an ability which is needed in problem solving. One of the ways in problem solving is influenced by Adversity Quotient (AQ). AQ is the power of facing difficulties. There are three categories of AQ namely climber, camper, and quitter. This research is a descriptive research using qualitative approach. The aim of this research is to describe flexibility in mathematics problem solving based on Adversity Quotient. The subjects of this research are climber student, camper student, and quitter student. This research was started by giving Adversity Response Profile (ARP) questioner continued by giving problem solving task and interviews. The validity of data measurement was using time triangulation. The results of this research shows that climber student uses two strategies in solving problem and doesn’t have difficulty. The camper student uses two strategies in solving problem but has difficulty to finish the second strategies. The quitter student uses one strategy in solving problem and has difficulty to finish it.

Managing PBL difficulties in an industrial engineering and management program

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Anabela Alves

2016-08-01

Full Text Available Purpose: Project-Based Learning (PBL is considered to be an active learning methodology which can be used to develop both technical and transversal competences in engineering programs. This methodology demands a great deal of work effort from the students and also from the teachers and it requires a meticulous plan and a well-managed project as well. These activities go far beyond the normal activities in traditional lectures, enabling to outpace the difficulties that spur along the way that may be both complex and demotivating. This methodology has been implemented in the Integrated Master Degree on Industrial Engineering and Management (IEM, at one public university in Portugal, since the 2004/2005 academic year. The aim of this paper is to identify and discuss the main difficulties of the implementation of PBL, mainly from the teachers’ perspectives. Additionally, some effective strategies will be recommended to overcome such difficulties. Design/methodology/approach: The perceptions of the teachers were collected through a survey based on six main themes. The participants in the study include eight teachers from the five courses of the first semester of the first year of the IEM program involved in the 2012/2013 and 2013/2014 editions. Findings: Integration of courses in the project; student assessment; growing number of students in each team and the need of physical spaces for them; and compartmentalized knowledge has emerged as the main difficulties. To overcome these difficulties some key strategies were recommended. Originality/value: A new perspective based on course teachers' views and experiences will deepen the understanding of the problems and provide inputs for the development of strategies that may improve the effectiveness of PBL and introduce changes for its successful implementation. These strategies are intended to be transferable to other contexts, as most of the problems and constraints are common to other active learning

Managing PBL difficulties in an industrial engineering and management program

International Nuclear Information System (INIS)

Alves, A.; Sousa, R.; Moreira, F.; Carvalho, M.A.; Cardoso, E.; Pimenta, P.; Malheiro, T.; Brito, I.; Fernandes, S.; Mesquita, D.

2016-01-01

Project-Based Learning (PBL) is considered to be an active learning methodology which can be used to develop both technical and transversal competences in engineering programs. This methodology demands a great deal of work effort from the students and also from the teachers and it requires a meticulous plan and a well-managed project as well. These activities go far beyond the normal activities in traditional lectures, enabling to outpace the difficulties that spur along the way that may be both complex and demotivating. This methodology has been implemented in the Integrated Master Degree on Industrial Engineering and Management (IEM), at one public university in Portugal, since the 2004/2005 academic year. The aim of this paper is to identify and discuss the main difficulties of the implementation of PBL, mainly from the teachers’ perspectives. Additionally, some effective strategies will be recommended to overcome such difficulties. Design/methodology/approach: The perceptions of the teachers were collected through a survey based on six main themes. The participants in the study include eight teachers from the five courses of the first semester of the first year of the IEM program involved in the 2012/2013 and 2013/2014 editions. Findings: Integration of courses in the project; student assessment; growing number of students in each team and the need of physical spaces for them; and compartmentalized knowledge has emerged as the main difficulties. To overcome these difficulties some key strategies were recommended. Originality/value: A new perspective based on course teachers' views and experiences will deepen the understanding of the problems and provide inputs for the development of strategies that may improve the effectiveness of PBL and introduce changes for its successful implementation. These strategies are intended to be transferable to other contexts, as most of the problems and constraints are common to other active learning approaches. (Author)

Managing PBL difficulties in an industrial engineering and management program

Energy Technology Data Exchange (ETDEWEB)

Alves, A.; Sousa, R.; Moreira, F.; Carvalho, M.A.; Cardoso, E.; Pimenta, P.; Malheiro, T.; Brito, I.; Fernandes, S.; Mesquita, D.

2016-07-01

Project-Based Learning (PBL) is considered to be an active learning methodology which can be used to develop both technical and transversal competences in engineering programs. This methodology demands a great deal of work effort from the students and also from the teachers and it requires a meticulous plan and a well-managed project as well. These activities go far beyond the normal activities in traditional lectures, enabling to outpace the difficulties that spur along the way that may be both complex and demotivating. This methodology has been implemented in the Integrated Master Degree on Industrial Engineering and Management (IEM), at one public university in Portugal, since the 2004/2005 academic year. The aim of this paper is to identify and discuss the main difficulties of the implementation of PBL, mainly from the teachers’ perspectives. Additionally, some effective strategies will be recommended to overcome such difficulties. Design/methodology/approach: The perceptions of the teachers were collected through a survey based on six main themes. The participants in the study include eight teachers from the five courses of the first semester of the first year of the IEM program involved in the 2012/2013 and 2013/2014 editions. Findings: Integration of courses in the project; student assessment; growing number of students in each team and the need of physical spaces for them; and compartmentalized knowledge has emerged as the main difficulties. To overcome these difficulties some key strategies were recommended. Originality/value: A new perspective based on course teachers' views and experiences will deepen the understanding of the problems and provide inputs for the development of strategies that may improve the effectiveness of PBL and introduce changes for its successful implementation. These strategies are intended to be transferable to other contexts, as most of the problems and constraints are common to other active learning approaches. (Author)

Modified quasi-boundary value method for Cauchy problems of elliptic equations with variable coefficients

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Hongwu Zhang

2011-08-01

Full Text Available In this article, we study a Cauchy problem for an elliptic equation with variable coefficients. It is well-known that such a problem is severely ill-posed; i.e., the solution does not depend continuously on the Cauchy data. We propose a modified quasi-boundary value regularization method to solve it. Convergence estimates are established under two a priori assumptions on the exact solution. A numerical example is given to illustrate our proposed method.

A geostatistical approach to the change-of-support problem and variable-support data fusion in spatial analysis

Science.gov (United States)

Wang, Jun; Wang, Yang; Zeng, Hui

2016-01-01

A key issue to address in synthesizing spatial data with variable-support in spatial analysis and modeling is the change-of-support problem. We present an approach for solving the change-of-support and variable-support data fusion problems. This approach is based on geostatistical inverse modeling that explicitly accounts for differences in spatial support. The inverse model is applied here to produce both the best predictions of a target support and prediction uncertainties, based on one or more measurements, while honoring measurements. Spatial data covering large geographic areas often exhibit spatial nonstationarity and can lead to computational challenge due to the large data size. We developed a local-window geostatistical inverse modeling approach to accommodate these issues of spatial nonstationarity and alleviate computational burden. We conducted experiments using synthetic and real-world raster data. Synthetic data were generated and aggregated to multiple supports and downscaled back to the original support to analyze the accuracy of spatial predictions and the correctness of prediction uncertainties. Similar experiments were conducted for real-world raster data. Real-world data with variable-support were statistically fused to produce single-support predictions and associated uncertainties. The modeling results demonstrate that geostatistical inverse modeling can produce accurate predictions and associated prediction uncertainties. It is shown that the local-window geostatistical inverse modeling approach suggested offers a practical way to solve the well-known change-of-support problem and variable-support data fusion problem in spatial analysis and modeling.

Variable Neighborhood Search for Parallel Machines Scheduling Problem with Step Deteriorating Jobs

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Wenming Cheng

2012-01-01

Full Text Available In many real scheduling environments, a job processed later needs longer time than the same job when it starts earlier. This phenomenon is known as scheduling with deteriorating jobs to many industrial applications. In this paper, we study a scheduling problem of minimizing the total completion time on identical parallel machines where the processing time of a job is a step function of its starting time and a deteriorating date that is individual to all jobs. Firstly, a mixed integer programming model is presented for the problem. And then, a modified weight-combination search algorithm and a variable neighborhood search are employed to yield optimal or near-optimal schedule. To evaluate the performance of the proposed algorithms, computational experiments are performed on randomly generated test instances. Finally, computational results show that the proposed approaches obtain near-optimal solutions in a reasonable computational time even for large-sized problems.

Resolución del Response Time Variability Problem mediante tabu search

OpenAIRE

Corominas Subias, Albert; García Villoria, Alberto; Pastor Moreno, Rafael

2009-01-01

El Response Time Variability Problem (RTVP) es un problema combinatorio de scheduling publicado recientemente en la literatura. Dicho problema de optimización combinatoria es muy fácil de formular pero muy difícil de resolver de forma exacta (es NP-hard). El RTVP se presenta cuando productos, clientes o tareas se han de secuenciar minimizando la variabilidad entre los instantes de tiempo en los que reciben los recursos que ellos necesitan. Este problema tiene una gran cantidad de aplicaciones...

Mental Health Problems of Iranian Female Adolescents and Its Association with Pubertal Development: A Nationwide Study

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Aria Sotoudeh

2012-03-01

Full Text Available Mental health problems including emotional and behavioral problems during puberty may be under influence of different risk factors including cultures, living in urban or rural areas and ethnic factors which may vary between different countries. The main aim of this study is to investigate the profile of emotional and behavioral problems and the role of factors such as age, stage of puberty, ethnicity, rurality and living in urban area, as risk factors in Iranian girls. As a part of a large national study we evaluated the emotional and behavioral problems in different stages of puberty in a community sample of Iranian adolescent girls from public schools that were selected by clustered random sampling method. In all subjects, demographic characteristics, and pubertal stages were measured. Emotional and behavioral problems were evaluated using Strength and Difficulties Questionnaire (SDQ. The associations of age, pubertal development indices, socioeconomic and demographic factors with the behavioral problems were assessed. A total number of 4576 students enrolled the study and responded to the questions. The mean age of participants was 13.83 2.19 years. The mean total score of difficulties in participants was 14.34 5.81. According to these results 813 (17.8% adolescents had total problem scores higher than Goodmans cutoff points and the most frequent problem domain was conduct problems (20.5%. According to the results the most related variable with the total difficulty score of SDQ were ethnicity, residency in urban areas and development of menstrual cycle respectively. The results of this study showed that the most correlated factors with mental health problems in Iranian girls during puberty are ethnicity, urbanity and development of menstrual cycle.

Self-reported difficulty in conceiving as a measure of infertility.

Science.gov (United States)

Dick, M-L B; Bain, C J; Purdie, D M; Siskind, V; Molloy, D; Green, A C

2003-12-01

This study aimed to explore the meaning and potential use of women's self-reported difficulties in conceiving as a measure of infertility in epidemiological studies, and to compare women's stated reasons for infertility with information in their medical records. Data were available from a population-based case-control study of ovarian cancer involving 1638 women. The sensitivity and specificity of women's self-reported infertility were calculated against their estimated fertility status based on detailed reproductive histories. Self-reported reasons for infertility were compared with diagnoses documented in women's medical records. The sensitivity of women's self-reported difficulty in conceiving was 66 and 69% respectively when compared with calendar-derived and self-reported times taken trying to conceive; its specificity was 95%. Forty-one (23%) of the 179 women for whom medical records were available had their self-reported fertility problem confirmed. Self-reported infertility causes could be compared with diagnoses in medical records for only 22 of these women. Self-reported difficulty conceiving is a useful measure of infertility for quantifying the burden of fertility problems experienced in the community. Validation of reasons for infertility is unlikely to be feasible through examination of medical records. Improved education of the public regarding the availability and success rates of infertility treatments is proposed.

Difficulties in Balint groups: a qualitative study of leaders' experiences.

Science.gov (United States)

Kjeldmand, Dorte; Holmström, Inger

2010-11-01

Balint groups (BGs) are a means of enhancing competence in the physician-patient relationship and are also regarded as beneficial for GPs' mental health. However, voluntary BGs are still few, some members terminate their participation, and problems are reported in obligatory groups in residency programmes. This raises questions about possible negative aspects of BGs. To examine difficulties in BGs as experienced by BG leaders. Qualitative study using interviews. Eight BG leaders from five countries were interviewed. The interviews focused on the informants' experiences of difficulties in their groups and were analysed with a systematic text-condensation method. Three categories of difficulties emerged from the analysis: 1) the individual physician having needs, vulnerabilities, and defences; 2) the group (including the leader) having problems of hidden agendas, rivalries, and frames; and 3) the surrounding environment defining the conditions of the group. BGs were found to fit into modern theories of small groups as complex systems. They are submitted to group dynamics that are sometimes malicious, and are exposed to often tough environmental conditions. Professionally conducted BGs seem to be a gentle, efficient method to train physicians, but with limitations. Participation of a member demands psychological stability and an open mind. BGs need support from the leadership of healthcare organisations in order to exist.

Feeding difficulties in children with food protein-induced gastrointestinal allergies.

Science.gov (United States)

Meyer, Rosan; Rommel, Nathalie; Van Oudenhove, Lukas; Fleming, Catharine; Dziubak, Robert; Shah, Neil

2014-10-01

There is paucity of data on the prevalence of feeding difficulties in Food Protein-Induced Gastrointestinal Allergies (FPIGA) and their clinical characteristics. However, it is a commonly reported problem by clinicians. We set out to establish the occurrence of feeding difficulties in children with FPIGA, the association with gastrointestinal and extra-intestinal symptoms and number of foods eliminated from the diet. This retrospective observational analysis was performed in patients seen between 2002 and 2009 at Great Ormond Street Children's Hospital, Gastroenterology Department, London. Medical records where FPIGA was documented using the terms from the National Institute of Allergy and Infectious Disease and National Institute of Clinical Excellence and confirmed using an elimination diet, followed by a challenge were included. Feeding difficulties were assessed using a criteria previously used in healthy toddlers in the UK. Data from 437 children (203 female) were collected. Significantly more children with feeding difficulties presented with abdominal distention and bloating (P = 0.002), vomiting (P foods eliminated from the diet in the children with/without feeding difficulties (P = 0.028). Clinical manifestations like vomiting, constipation, rectal bleeding, weight loss, and the presence of extra-intestinal manifestations in addition to the number of foods avoided are in our FPIGA population linked to feeding difficulties. © 2014 Journal of Gastroenterology and Hepatology Foundation and Wiley Publishing Asia Pty Ltd.

How 'core' are motor timing difficulties in ADHD? A latent class comparison of pure and comorbid ADHD classes

NARCIS (Netherlands)

van der Meer, Jolanda M. J.; Hartman, Catharina A.; Thissen, Andrieke J. A. M.; Oerlemans, Anoek M.; Luman, Marjolein; Buitelaar, Jan K.; Rommelse, Nanda N. J.

Children with attention-deficit/hyperactivity disorder (ADHD) have motor timing difficulties. This study examined whether affected motor timing accuracy and variability are specific for ADHD, or that comorbidity with autism spectrum disorders (ASD) contributes to these motor timing difficulties. An

Adolescents with a history of specific language impairment (SLI): strengths and difficulties in social, emotional and behavioral functioning.

Science.gov (United States)

Conti-Ramsden, Gina; Mok, Pearl L H; Pickles, Andrew; Durkin, Kevin

2013-11-01

Adolescents with specific language impairment (SLI) are at a greater risk of emotional and behavioral problems compared to their typically developing (TD) peers, but little is known about their self-perceived strengths and difficulties. In this study, the self-reported social, emotional and behavioral functioning of 139 adolescents with a history of SLI and 124 TD individuals at age 16 was examined. The self-report version of the Strengths and Difficulties Questionnaire (SDQ) was used to assess their prosocial behavior and levels of peer, emotional and behavioral difficulties. Associations of these areas of functioning with gender, verbal and non-verbal skills were also investigated. Adolescents with a history of SLI were more likely than their TD peers to report higher levels of peer problems, emotional symptoms, hyperactivity and conduct problems. The majority of adolescents in both groups (87% SLI and 96% TD), however, reported prosocial behavior within the typical range. Difficulty with peer relations was the strongest differentiator between the groups, with the odds of reporting borderline or abnormally high levels of peer problems being 12 times higher for individuals with a history of SLI. Adolescents with poorer receptive language skills were also more likely to report higher levels of emotional and behavioral difficulties. The findings of this study identify likely traits that may lead to referral to services. Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.

Development and Validation of a Rubric for Diagnosing Students’ Experimental Design Knowledge and Difficulties

Science.gov (United States)

Dasgupta, Annwesa P.; Anderson, Trevor R.

2014-01-01

It is essential to teach students about experimental design, as this facilitates their deeper understanding of how most biological knowledge was generated and gives them tools to perform their own investigations. Despite the importance of this area, surprisingly little is known about what students actually learn from designing biological experiments. In this paper, we describe a rubric for experimental design (RED) that can be used to measure knowledge of and diagnose difficulties with experimental design. The development and validation of the RED was informed by a literature review and empirical analysis of undergraduate biology students’ responses to three published assessments. Five areas of difficulty with experimental design were identified: the variable properties of an experimental subject; the manipulated variables; measurement of outcomes; accounting for variability; and the scope of inference appropriate for experimental findings. Our findings revealed that some difficulties, documented some 50 yr ago, still exist among our undergraduate students, while others remain poorly investigated. The RED shows great promise for diagnosing students’ experimental design knowledge in lecture settings, laboratory courses, research internships, and course-based undergraduate research experiences. It also shows potential for guiding the development and selection of assessment and instructional activities that foster experimental design. PMID:26086658

Improving Language Comprehension in Preschool Children with Language Difficulties: A Cluster Randomized Trial

Science.gov (United States)

Hagen, Åste M.; Melby-Lervåg, Monica; Lervåg, Arne

2017-01-01

Background: Children with language comprehension difficulties are at risk of educational and social problems, which in turn impede employment prospects in adulthood. However, few randomized trials have examined how such problems can be ameliorated during the preschool years. Methods: We conducted a cluster randomized trial in 148 preschool…

Contributions of physical and cognitive impairments to self-reported driving difficulty in chronic whiplash-associated disorders.

Science.gov (United States)

Takasaki, Hiroshi; Treleaven, Julia; Johnston, Venerina; Jull, Gwendolen

2013-08-15

Cross-sectional. To conduct a preliminary analysis of the physical, cognitive, and psychological domains contributing to self-reported driving difficulty after adjusting for neck pain, dizziness, and relevant demographics in chronic whiplash-associated disorders (WAD) using hierarchical regression modeling. Pain is a risk factor for car crashes, and dizziness may affect fitness to drive. Both symptoms are common in chronic WAD and difficulty driving is a common complaint in this group. Chronic WAD is often accompanied by physical, cognitive, and psychological impairments. These impairments may contribute to self-reported driving difficulty beyond neck pain, dizziness, and relevant demographics. Forty individuals with chronic WAD participated. Dependent variables were the magnitude of self-reported driving difficulty assessed in the strategic, tactical, and operational levels of the Neck Pain Driving Index. Three models were developed to assess the contributions of independent variables (physical, cognitive, and psychological domains) to each of the 3 dependent variables after adjusting for neck pain intensity, dizziness, and driving demographics. The measures included were: physical domain-range and maximum speed of head rotation, performances during gaze stability, eye-head coordination, and visual dependency tests; cognitive domain-self-reported cognitive symptoms including fatigue and the trail making tests; and psychological domain-general stress, traumatic stress, depression, and fear of neck movements and driving. Symptom duration was relevant to driving difficulty in the strategic and tactical levels. The cognitive domain increased statistical power to estimate the strategic and operational levels (P < 0.1) beyond other contributors. The physical domain increased statistical power to estimate the tactical level (P < 0.1) beyond other contributors. Physical and cognitive impairments independently contributed to self-reported driving difficulty in chronic WAD

Psychological difficulties among children and adolescents with ethnic Danish, immigrant or refugee background

DEFF Research Database (Denmark)

Leth, Ingrid; Niclasen, Janni; Ryding, Else

2014-01-01

Objective: This study investigated and compared the prevalence of psychological difficulties among Danish, immigrant, and refugee children. Methods: We enrolled 332 children between the ages of 8 and 18 years (148 Danish children, 81 immigrant children, and 67 children with refugee backgrounds....... No significant differences with regard to age or gender were found among the groups. Conclusions: Our data suggest that, although immigrant children had higher levels of conduct problems than ethnic Danish children, they did not suffer from higher levels of internalizing psychological difficulties. However......, refugee children were at higher risk for psychological difficulties associated with both externalizing and internalizing....

Numerical difficulties associated with using equality constraints to achieve multi-level decomposition in structural optimization

Science.gov (United States)

Thareja, R.; Haftka, R. T.

1986-01-01

There has been recent interest in multidisciplinary multilevel optimization applied to large engineering systems. The usual approach is to divide the system into a hierarchy of subsystems with ever increasing detail in the analysis focus. Equality constraints are usually placed on various design quantities at every successive level to ensure consistency between levels. In many previous applications these equality constraints were eliminated by reducing the number of design variables. In complex systems this may not be possible and these equality constraints may have to be retained in the optimization process. In this paper the impact of such a retention is examined for a simple portal frame problem. It is shown that the equality constraints introduce numerical difficulties, and that the numerical solution becomes very sensitive to optimization parameters for a wide range of optimization algorithms.

Using problem-solving instruction to overcome high school ...

African Journals Online (AJOL)

kofi.mereku

identified difficulties in comparison to the conventional lecture method. ... important for chemistry educators to be aware of the difficulties students encounter as they learn .... these concepts before the can solve quantitative numerical problems. Secondly ... development of stepped supporting tools for stoichiometric problems, ...

Behavioral Executive Functions Among Adolescents With Mathematics Difficulties.

Science.gov (United States)

Holm, Marja E; Aunio, Pirjo; Björn, Piia M; Klenberg, Liisa; Korhonen, Johan; Hannula, Markku S

2017-07-01

This study investigates behavioral executive functions (EFs) in the mathematics classroom context among adolescents with different mathematics performance levels. The EF problems were assessed by teachers using a behavioral rating inventory. Using cutoff scores on a standardized mathematics assessment, groups with mathematics difficulties (MD; n = 124), low mathematics performance (LA; n = 140), and average or higher scores (AC; n = 355) were identified. Results showed that the MD group had more problems with distractibility, directing attention, shifting attention, initiative, execution of action, planning, and evaluation than the LA group, whereas the differences in hyperactivity, impulsivity, and sustaining attention were not significant. Compared to the AC group, the MD group showed more problems with all behavioral EFs except hyperactivity and impulsivity, while the LA group showed more problems only with shifting attention. Male adolescents showed more behavioral EF problems than female adolescents, but this gender difference was negligible within the MD group. The practical implications of the results are discussed.

Multi-objective flexible job shop scheduling problem using variable neighborhood evolutionary algorithm

Science.gov (United States)

Wang, Chun; Ji, Zhicheng; Wang, Yan

2017-07-01

In this paper, multi-objective flexible job shop scheduling problem (MOFJSP) was studied with the objects to minimize makespan, total workload and critical workload. A variable neighborhood evolutionary algorithm (VNEA) was proposed to obtain a set of Pareto optimal solutions. First, two novel crowded operators in terms of the decision space and object space were proposed, and they were respectively used in mating selection and environmental selection. Then, two well-designed neighborhood structures were used in local search, which consider the problem characteristics and can hold fast convergence. Finally, extensive comparison was carried out with the state-of-the-art methods specially presented for solving MOFJSP on well-known benchmark instances. The results show that the proposed VNEA is more effective than other algorithms in solving MOFJSP.

All ternary permutation constraint satisfaction problems parameterized above average have kernels with quadratic numbers of variables

DEFF Research Database (Denmark)

Gutin, Gregory; Van Iersel, Leo; Mnich, Matthias

2010-01-01

A ternary Permutation-CSP is specified by a subset Π of the symmetric group S3. An instance of such a problem consists of a set of variables V and a multiset of constraints, which are ordered triples of distinct variables of V. The objective is to find a linear ordering α of V that maximizes...... the number of triples whose rearrangement (under α) follows a permutation in Π. We prove that all ternary Permutation-CSPs parameterized above average have kernels with quadratic numbers of variables....

Student Difficulties Regarding Symbolic and Graphical Representations of Vector Fields

Science.gov (United States)

Bollen, Laurens; van Kampen, Paul; Baily, Charles; Kelly, Mossy; De Cock, Mieke

2017-01-01

The ability to switch between various representations is an invaluable problem-solving skill in physics. In addition, research has shown that using multiple representations can greatly enhance a person's understanding of mathematical and physical concepts. This paper describes a study of student difficulties regarding interpreting, constructing,…

Undergraduate ESL Students’ Difficulties in Writing the Introduction for Research Reports

Directory of Open Access Journals (Sweden)

Mirrah Diyana Binti Maznun

2017-02-01

Full Text Available This study was conducted to investigate the difficulties encountered by undergraduate ESL students in writing the introduction section of their project reports. Five introduction sections of bachelor of arts students, majoring in English language, were analyzed and a lecturer was interviewed regarding the areas of the students’ weaknesses. Swales’ create-a-research-space (cars model was used as the analytical framework of the study. The results revealed that students confronted problems in writing their introduction for each move especially for move 2, which consists of counter claiming, indicating research gap, raising questions from previous research and continuing tradition. It was also found that the students had difficulty in writing the background of the study, theoretical framework, and statement of the problem which indicated their unawareness of the appropriate rhetorical structure of the introduction section.

Wormholes and the cosmological constant problem.

Science.gov (United States)

Klebanov, I.

The author reviews the cosmological constant problem and the recently proposed wormhole mechanism for its solution. Summation over wormholes in the Euclidean path integral for gravity turns all the coupling parameters into dynamical variables, sampled from a probability distribution. A formal saddle point analysis results in a distribution with a sharp peak at the cosmological constant equal to zero, which appears to solve the cosmological constant problem. He discusses the instabilities of the gravitational Euclidean path integral and the difficulties with its interpretation. He presents an alternate formalism for baby universes, based on the "third quantization" of the Wheeler-De Witt equation. This approach is analyzed in a minisuperspace model for quantum gravity, where it reduces to simple quantum mechanics. Once again, the coupling parameters become dynamical. Unfortunately, the a priori probability distribution for the cosmological constant and other parameters is typically a smooth function, with no sharp peaks.

Children's difficulty with true belief tasks: Competence deficit or performance problem?

Science.gov (United States)

Oktay-Gür, Nese; Rakoczy, Hannes

2017-09-01

According to the standard picture of explicit theory of mind (ToM) development, children begin to (explicitly) ascribe beliefs to others and themselves from around age 4. The empirical basis of this picture comes from numerous studies consistently showing that children master verbal false belief (FB) tasks from around age 4 while children much younger have no difficulty in mastering structurally analogous true belief (TB) tasks. The standard picture, though, has come under serious attack from recent studies using TB tasks with wider age ranges. These studies have found that, paradoxically, children begin to fail TB tasks once they master FB tasks. Such findings cast doubt on the standard picture and suggest, instead, that FB tasks may be solved by much simpler strategies than proper belief reasoning. In the present study, we tested for the development of FB and TB performance in comprehensive and systematic ways. In particular, we tested the competing predictions of competence accounts (according to which TB failure reflects lack of conceptual competence) versus performance limitation accounts (according to which the standard picture is true yet children from around age 4 fail TB tasks due to performance factors). Studies 1 and 2 showed that performance in a variety of novel TB tasks showed a clear U-shaped curve, with children until age 3 and from age 10 performing competently and children in between failing, with strong negative correlations between TB and FB. Crucially, these patterns were found for various kinds of TB tasks, including those for which existing competence limitation accounts would not even predict any difficulty. Study 3, therefore, directly tested performance limitation accounts in terms of pragmatic and related factors and found that these patterns (failure in TB and negative TB-FB correlations) disappear once the relevant performance factors have been removed from the TB tasks. Taken together, these findings suggest that previous TB findings

Investigating Pre-Service Science Teachers' Critical Thinking Dispositions and Problem Solving Skills in Terms of Different Variables

Science.gov (United States)

Yenice, Nilgun

2011-01-01

This study was conducted to examine pre-service science teachers' critical thinking dispositions and problem solving skills based on gender, grade level and graduated high school variables. Also relationship between pre-service science teachers' critical thinking dispositions and problem solving skills was examined based on gender, grade level and…

Learning difficulties of senior high school students based on probability understanding levels

Science.gov (United States)

Anggara, B.; Priatna, N.; Juandi, D.

2018-05-01

Identifying students' difficulties in learning concept of probability is important for teachers to prepare the appropriate learning processes and can overcome obstacles that may arise in the next learning processes. This study revealed the level of students' understanding of the concept of probability and identified their difficulties as a part of the epistemological obstacles identification of the concept of probability. This study employed a qualitative approach that tends to be the character of descriptive research involving 55 students of class XII. In this case, the writer used the diagnostic test of probability concept learning difficulty, observation, and interview as the techniques to collect the data needed. The data was used to determine levels of understanding and the learning difficulties experienced by the students. From the result of students' test result and learning observation, it was found that the mean cognitive level was at level 2. The findings indicated that students had appropriate quantitative information of probability concept but it might be incomplete or incorrectly used. The difficulties found are the ones in arranging sample space, events, and mathematical models related to probability problems. Besides, students had difficulties in understanding the principles of events and prerequisite concept.

The Effect of Question Format and Task Difficulty on Reasoning Strategies and Diagnostic Performance in Internal Medicine Residents

Science.gov (United States)

Heemskerk, Laura; Norman, Geoff; Chou, Sophia; Mintz, Marcy; Mandin, Henry; McLaughlin, Kevin

2008-01-01

Background: Previous studies have suggested an association between reasoning strategies and diagnostic success, but the influence on this relationship of variables such as question format and task difficulty, has not been studied. Our objective was to study the association between question format, task difficulty, reasoning strategies and…

Numerical Magnitude Representation in Children With Mathematical Difficulties With or Without Reading Difficulties.

Science.gov (United States)

Tobia, Valentina; Fasola, Anna; Lupieri, Alice; Marzocchi, Gian Marco

2016-01-01

This study aimed to explore the spatial numerical association of response codes (SNARC), the flanker, and the numerical distance effects in children with mathematical difficulties. From a sample of 720 third, fourth, and fifth graders, 60 children were selected and divided into the following three groups: typically developing children (TD; n = 29), children with mathematical difficulties only (MD only; n = 21), and children with mathematical and reading difficulties (MD+RD; n = 10). Children were tested with a numerical Eriksen task that was built to assess SNARC, numerical distance, and flanker (first and second order congruency) effects. Children with MD only showed stronger SNARC and second order congruency effects than did TD children, whereas the numerical distance effects were similar across the three groups. Finally, the first order congruency effect was associated with reading difficulties. These results showed that children with mathematical difficulties with or without reading difficulties were globally more impaired when spatial incompatibilities were presented. © Hammill Institute on Disabilities 2014.

Alone? Perceived social support and chronic interpersonal difficulties in suicidal elders.

Science.gov (United States)

Harrison, Katrin E; Dombrovski, Alexandre Y; Morse, Jennifer Q; Houck, Patricia; Schlernitzauer, Maryann; Reynolds, Charles F; Szanto, Katalin

2010-05-01

Social networks may protect depressed elders against suicidal behavior. However, conflict in important relationships may undermine the sense of social support, potentially negating the protective effects. Thus, we investigated the role of chronic interpersonal difficulties and perceived social support in depressed elders with and without suicidal thoughts and attempts. 106 individuals aged 60 years and older participated in this cross-sectional, case-control study. They were placed in three groups: suicidal depressed, non-suicidal depressed and non-depressed. Following a detailed clinical characterization, we assessed perceived social support (Interpersonal Support Evaluation List), and chronic interpersonal difficulties (Inventory of Interpersonal Problems). Using general linear models, we explored the relationship between suicidal thoughts/attempts, social support, and chronic interpersonal difficulties. We also examined whether lower perceived social support explained the relationship between chronic interpersonal difficulties and suicidal thoughts/attempts. Suicidal depressed elders reported the lowest levels of perceived social support (belonging, tangible support, and self-esteem) and higher levels of chronic interpersonal difficulties (struggle against others and interpersonal hostility), compared to both non-suicidal depressed and non-depressed elders. The relationship between chronic interpersonal difficulties and suicidal behavior was partially explained by low perceived social support. The experience of strong affects, interpersonal struggle, and hostility in relationships may undermine the sense of social support in depressed elders, possibly leading them to contemplate or attempt suicide. Depressed elders with a history of interpersonal difficulties need to be carefully monitored for suicidal behavior.

Variability of worked examples and transfer of geometrical problem-solving skills : a cognitive-load approach

NARCIS (Netherlands)

Paas, Fred G.W.C.; van Merrienboer, Jeroen J.G.; van Merrienboer, J.J.G.

1994-01-01

Four computer-based training strategies for geometrical problem solving in the domain of computer numerically controlled machinery programming were studied with regard to their effects on training performance, transfer performance, and cognitive load. A low- and a high-variability conventional

Learners with learning difficulties in mathematics : attitudes, curriculum and methods of teaching mathematics

OpenAIRE

2012-01-01

D.Ed. The aim of this theses is to find out whether there is any relationship between learners' attitudes and learning difficulties in mathematics: To investigate whether learning difficulties in mathematics are associated with learners' gender. To establish the nature of teachers' perceptions of the learning problem areas in the mathematics curriculum. To find out about the teachers' views on the methods of teaching mathematics, resources, learning of mathematics, extra curricular activit...

Difficulties in modeling dispersed-flow film boiling

International Nuclear Information System (INIS)

Andreani, M.; Yadigaroglu, G.

1991-01-01

Dispersed Flow Film Boiling (DFFB) is characterized by important departures from thermal and velocity equilibrium that make it suitable for modeling with two-fluid models. The fundamental limitations and difficulties imposed by the one-dimensional nature of these models are extensively discussed. The validity of the assumptions and empirical laws used to close the system of conservation equations is critically reviewed, in light of the multidimensional aspects of the problem. Modifications that could improve the physics of the models are identified. (orig.) [de

Identification problems in linear transformation system

International Nuclear Information System (INIS)

Delforge, Jacques.

1975-01-01

An attempt was made to solve the theoretical and numerical difficulties involved in the identification problem relative to the linear part of P. Delattre's theory of transformation systems. The theoretical difficulties are due to the very important problem of the uniqueness of the solution, which must be demonstrated in order to justify the value of the solution found. Simple criteria have been found when measurements are possible on all the equivalence classes, but the problem remains imperfectly solved when certain evolution curves are unknown. The numerical difficulties are of two kinds: a slow convergence of iterative methods and a strong repercussion of numerical and experimental errors on the solution. In the former case a fast convergence was obtained by transformation of the parametric space, while in the latter it was possible, from sensitivity functions, to estimate the errors, to define and measure the conditioning of the identification problem then to minimize this conditioning as a function of the experimental conditions [fr

Variables cognitivas y metacognitivas en la resolución de problemas de química: propuesta de estrategias didácticas Cognitive and metacognitive variables in chemistry problem solving: a proposal of didactic strategies

Directory of Open Access Journals (Sweden)

Joan Josep Solaz-Portolés

2010-01-01

Full Text Available This paper presents and classifies the cognitive and metacognitive variables involved in the processes that students execute in problem solving. Moreover, it shows how these variables affect the students success in problem solving. These variables are classified in: piagetian and neo-piagetian, representational, metacognitive and transfer of learning. In the first group of variables it is discussed formal reasoning ability and other neo-piagetian factors. In the second group of variables it is analysed mental models and external representations. Implications for chemistry education are collected as a proposal of didactic strategies in the classroom.

Associations between school difficulties and health-related problems and risky behaviours in early adolescence: A cross-sectional study in middle-school adolescents in France.

Science.gov (United States)

Chau, Kénora; Kabuth, Bernard; Causin-Brice, Odile; Delacour, Yves; Richoux-Picard, Catherine; Verdin, Monique; Armand, Isabelle; Chau, Nearkasen

2016-10-30

Health-related problems and risky behaviours (substance use) are frequent in adolescents, may alter their physical and mental capabilities, and may thus generate school absenteeism, low academic performance, and school dropout ideation. This study assessed their associations and the contribution of socioeconomic factors among 1559 middle-school adolescents (mean age 13.5+1.3) from north-eastern France. They completed a questionnaire including socioeconomic characteristics, health-related problems (poor physical health, psychological health, social relationships, and living environment) assessed with the World Health Organization's quality of life measure (scoreschool absences during the present school year, last-trimester academic performance, and school dropout ideation. Data were analysed using logistic regression models. School absenteeism was frequent (12.6% of subjects for 8-14 days, and 6.0% for ≥15 days); 8.2% of subjects had low academic performance (average school-mark school dropout ideation. All school difficulties were strongly associated with all health-related problems (gender-age-school-level-adjusted odds ratios gasOR between 1.5 and 4.2), and with risky behaviours (gasOR between 1.4 and 14). Socioeconomic factors differently contributed to these associations (contribution reaching 77%). Policy makers, schools, physicians and parents should be more aware of the problems and help adolescents to reduce health-related problems and risky behaviours and to increase resilience. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effectiveness of a self-regulated remedial program for handwriting difficulties.

Science.gov (United States)

Van Waelvelde, Hilde; De Roubaix, Amy; Steppe, Lien; Troubleyn, Evy; De Mey, Barbara; Dewitte, Griet; Debrabant, Julie; Van de Velde, Dominique

2017-09-01

Handwriting difficulties may have pervasive effects on a child's school performance. I Can! is a remedial handwriting program with a focus on self-regulated learning and applying motor learning principles combined with a behavioural approach. It is developed for typically developing children with handwriting problems. The study aim was to evaluate the program's effectiveness. Thirty-one children aged 7-8 year participated in a cross-over study. Handwriting quality and speed were repeatedly assessed by means of the Systematic Screening of Handwriting Difficulties test. Difficulties addressed were fluency in letter formation, fluency in letter connections, letter height, regularity of letter height, space between words, and line path. Mixed model analysis revealed improved quality of writing and speed for all children but significantly more improvement in handwriting quality for the children participating in the program. Although writing speed improved over time, no additional effects of the program occurred. 'I Can!' is found to be an effective instructive program to ameliorate handwriting quality in typically developing children with handwriting difficulties. The program's success was by a therapy burst of only 7 weeks focusing on the child's self-regulated learning capacities, within an individualized education plan according to their needs and goals.

The Relationship of Behavioral Activation and Inhibition Systems (BAS/BIS, Difficulty of Emotional Regulation, Metacognition with Worry

Directory of Open Access Journals (Sweden)

S. Soltan Mohammadlou

2014-11-01

Full Text Available Worry is a popular phenomenon and a common feature of many disorders, especially anxiety disorders. The objective of the study was to predict worry by using three predictive factors related to biological, emotional and cognition areas. In this study, behavioral inhibition, behavioral activation system, difficulties in emotion regulation and metacognition were examined as predictive variables. In a correlation cross-sectional design, 234 Medical Group students [BA and MA] of Tehran University of Medical Sciences participated in this study by using cluster sampling. The students completed these scales: Behavioral Inhibition and Behavioral Activation Systems (BAS/BIS, Difficulty of Emotion Regulation Scale (DERS, Metacognition Questionnaire-30 (MCQ-30 and Penn State Worry Questionnaire (PSWQ. Behavioral inhibition system, difficulty of emotion rgulation and metacognition variables were significantly positively correlated with worry (P<0/0 1(. Behavioral activation system variable was not significantly associated with worry. Stepwise multiple regression analysis indicated a predictive model for worry in which behavioral inhibition system, difficulty of emotional regulation and metacognition were its components respectively. Behavioral activation system was not included in the model. The findings of this study that worry should be studied in different biological, emotional, and metacognitive aspects. The results also emphasize the role of behavioral inhibition system as a temperamental and biological factor in psychopathology of worry in adult population.

Behavior problems at ages 6 and 11 and high school academic achievement: longitudinal latent variable modeling.

Science.gov (United States)

Breslau, Naomi; Breslau, Joshua; Miller, Elizabeth; Raykov, Tenko

2011-02-28

Previous studies documented long-run effects of behavior problems at the start of school on academic achievement. However, these studies did not examine whether the observed effects of early behavior problems are explained by more proximate behavior problems, given the tendency of children's behavior problems to persist. Latent variable modeling was applied to estimate the effects of behavior problems at ages 6 and 11 on academic achievement at age 17, using data from a longitudinal study (n=823). Behavior problems at ages 6 and 11, each stage independently of the other, predicted lower math and reading test scores at age 17, controlling for intelligence quotient (IQ), birth weight, maternal characteristics, family and community environment, and taking into account behavior problems at age 17. Behavior problems at the start of school, independent of later behavior problems, exert lingering effects on achievement by impeding the acquisition of cognitive skills that are the foundation for later academic progress. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

New Problems and Solutions in Basic University Teaching

Science.gov (United States)

Olesen, Mogens Noergaard

2008-01-01

In this paper we will examine some of the problems and difficulties in modern university teaching and how these difficulties were overcome and the problems were solved. Because the syllabus in Danish (and other European) high schools has been substantially weakened over the last decade and especially since 2002, the university students have…

FEEDING DIFFICULTIES IN PRESCHOOL CHILDREN, PREVIOUS FEEDING PRACTICES, AND NUTRITIONAL STATUS.

Science.gov (United States)

Maranhão, Hélcio de Sousa; Aguiar, Renata Cunha de; Lira, Débora Teixeira Jales de; Sales, Mônica Úrsula Figuerêdo; Nóbrega, Nathalia Ávila do Nascimento

2018-01-01

To identify the prevalence of feeding difficulties in preschoolers, its association with epidemiological factors and previous eating habits, and repercussion on nutritional status. Cross-sectional study with a questionnaire given to the mothers of 301 children aged 2-6 years enrolled in public and private kindergartens in Natal, Northeast Brazil, conducted in 2014-2015. Feeding difficulty was assessed according to Kerzner's criteria, resulting in the profiles "highly selective intake", "active child with small appetite", "fear of feeding", and "child with psychological disorder or neglected". Association with the following independent variables was analyzed by logistic regression: breastfeeding time, age of cows' milk and complementary feeding introduction, age range, family income, type of school, mothers' profile (responsive or nonresponsive), and body mass index (BMI). Feeding difficulty was found in 37.2% of cases, with predominance of "highly selective intake" (25.4%). It was not associated with infancy feeding practices, family income or type of school. There were no differences between the BMI Z score means for the groups with and without feeding difficulty (1.0±1.5 SD and 1.1±1.4 SD, respectively). The five-to-six age range had more occurrences (OR 1.8; 95%CI 1.1-2.9). Children of responsive mothers were less likely to have feeding difficulties (OR 0.4; 95%CI 0.2-0.8). Feeding difficulties were very frequent. Nutritional status was not impacted by it, and infancy eating habits were not associated with it. Responsive mothers' profile is a protective factor against eating difficulties and reinforces the importance of behavioral factors and mother-child interaction.

Analysis of 4th Grade Students' Problem Solving Skills in Terms of Several Variables

Science.gov (United States)

Sungur, Gülcan; Bal, Pervin Nedim

2016-01-01

The aim of this study is to examine if the level of primary school students in solving problems differs according to some demographic variables. The research is descriptive type in the general survey method, it was carried out with quantitative research techniques. The sample of the study consisted of 587 primary school students in Grade 4. The…

Current nuclear employees with psychological difficulties: prevalence, assessment, and disposition

International Nuclear Information System (INIS)

Sajwaj, T.; Chardos, S.; Lavin, P.; Ford, T.; McGee, R.K.

1987-01-01

Although industry standards and federal regulations require employees of nuclear power plants to demonstrate psychological stability and sound judgment before being initially granted unescorted access to the plant, it is obvious that emotional difficulties can develop subsequently. The development of emotional problems in current plant employees raises concerns about the safety of the public and the plant, the effectiveness of the organizations, the loss of important technical skills and experience, and the human cost to the employee and his/her family. This paper reports the experience of the Tennessee Valley Authority (TVA) in cases of reconsideration of psychological clearance of unescorted access, i.e., the review of psychological clearances of nuclear plant employees who have developed psychological difficulties

Response-rate differences in variable-interval and variable-ratio schedules: An old problem revisited

OpenAIRE

Cole, Mark R.

1994-01-01

In Experiment 1, a variable-ratio 10 schedule became, successively, a variable-interval schedule with only the minimum interreinforcement intervals yoked to the variable ratio, or a variable-interval schedule with both interreinforcement intervals and reinforced interresponse times yoked to the variable ratio. Response rates in the variable-interval schedule with both interreinforcement interval and reinforced interresponse time yoking fell between the higher rates maintained by the variable-...

Student Obstacles in Solving Algebraic Thinking Problems

Science.gov (United States)

Andini, W.; Suryadi, D.

2017-09-01

The aim of this research is to analize the student obstacles on solving algebraic thinking problems in low grades elementary school. This research is a preliminary qualitative research, and involved 66 students of grade 3 elementary school. From the analysis student test results, most of student experience difficulty in solving algebraic thinking problems. The main obstacle is the student’s difficulty in understanding the problem of generalizing the pattern because the students are not accustomed to see the rules that exist in generalize the pattern.

Cumulative risk effects for the development of behaviour difficulties in children and adolescents with special educational needs and disabilities.

Science.gov (United States)

Oldfield, Jeremy; Humphrey, Neil; Hebron, Judith

2015-01-01

Research has identified multiple risk factors for the development of behaviour difficulties. What have been less explored are the cumulative effects of exposure to multiple risks on behavioural outcomes, with no study specifically investigating these effects within a population of young people with special educational needs and disabilities (SEND). Furthermore, it is unclear whether a threshold or linear risk model better fits the data for this population. The sample included 2660 children and 1628 adolescents with SEND. Risk factors associated with increases in behaviour difficulties over an 18-month period were summed to create a cumulative risk score, with this explanatory variable being added into a multi-level model. A quadratic term was then added to test the threshold model. There was evidence of a cumulative risk effect, suggesting that exposure to higher numbers of risk factors, regardless of their exact nature, resulted in increased behaviour difficulties. The relationship between risk and behaviour difficulties was non-linear, with exposure to increasing risk having a disproportionate and detrimental impact on behaviour difficulties in child and adolescent models. Interventions aimed at reducing behaviour difficulties need to consider the impact of multiple risk variables. Tailoring interventions towards those exposed to large numbers of risks would be advantageous. Copyright © 2015 Elsevier Ltd. All rights reserved.

Dorso-Lateral Frontal Cortex of the Ferret Encodes Perceptual Difficulty during Visual Discrimination.

Science.gov (United States)

Zhou, Zhe Charles; Yu, Chunxiu; Sellers, Kristin K; Fröhlich, Flavio

2016-03-30

Visual discrimination requires sensory processing followed by a perceptual decision. Despite a growing understanding of visual areas in this behavior, it is unclear what role top-down signals from prefrontal cortex play, in particular as a function of perceptual difficulty. To address this gap, we investigated how neurons in dorso-lateral frontal cortex (dl-FC) of freely-moving ferrets encode task variables in a two-alternative forced choice visual discrimination task with high- and low-contrast visual input. About two-thirds of all recorded neurons in dl-FC were modulated by at least one of the two task variables, task difficulty and target location. More neurons in dl-FC preferred the hard trials; no such preference bias was found for target location. In individual neurons, this preference for specific task types was limited to brief epochs. Finally, optogenetic stimulation confirmed the functional role of the activity in dl-FC before target touch; suppression of activity in pyramidal neurons with the ArchT silencing opsin resulted in a decrease in reaction time to touch the target but not to retrieve reward. In conclusion, dl-FC activity is differentially recruited for high perceptual difficulty in the freely-moving ferret and the resulting signal may provide top-down behavioral inhibition.

[Executive functioning and motivation in preschool children at risk for learning difficulties in mathematics].

Science.gov (United States)

Presentación-Herrero, M Jesús; Mercader-Ruiz, Jessica; Siegenthaler-Hierro, Rebeca; Fernández-Andrés, Inmaculada; Miranda-Casas, Ana

2015-02-25

Early identification of the factors involved in the development of learning difficulties in mathematics is essential to be able to understand their origin and implement successful interventions. This study analyses the capacity of executive functioning and of variables from the motivational belief system to differentiate and classify preschool children with and without risk of having difficulties in mathematics. A total of 146 subjects from the third year of preschool education took part in the study, divided into risk/no risk according to the score obtained on the operations subtest of the TEDI-MATH test. Working memory (verbal and visuospatial) and inhibition (with auditory and visual stimuli) neuropsychological tasks were applied. Teachers filled in a questionnaire on the children's motivation with regard to learning. Significant differences were found between the two groups on the working memory and inhibition-auditory factors, as well as on all the motivation variables. The results also show a similar power of classification, with percentages above 80%, for both groups of variables. The implications of these findings for educational practice are discussed.

A multilevel variable neighborhood search heuristic for a practical vehicle routing and driver scheduling problem

DEFF Research Database (Denmark)

Wen, Min; Krapper, Emil; Larsen, Jesper

2011-01-01

in their fresh meat supply logistics system. The problem consists of a 1‐week planning horizon, heterogeneous vehicles, and drivers with predefined work regulations. These regulations include, among other things, predefined workdays, fixed starting time, maximum weekly working duration, and a break rule......The world's second largest producer of pork, Danish Crown, also provides a fresh meat supply logistics system within Denmark. This is used by the majority of supermarkets in Denmark. This article addresses an integrated vehicle routing and driver scheduling problem arising at Danish Crown....... The objective is to minimize the total delivery cost that is a weighted sum of two kinds of delivery costs. A multilevel variable neighborhood search heuristic is proposed for the problem. In a preprocessing step, the problem size is reduced through an aggregation procedure. Thereafter, the aggregated weekly...

A Hybrid Symbiotic Organisms Search Algorithm with Variable Neighbourhood Search for Solving Symmetric and Asymmetric Traveling Salesman Problem

Science.gov (United States)

Umam, M. I. H.; Santosa, B.

2018-04-01

Combinatorial optimization has been frequently used to solve both problems in science, engineering, and commercial applications. One combinatorial problems in the field of transportation is to find a shortest travel route that can be taken from the initial point of departure to point of destination, as well as minimizing travel costs and travel time. When the distance from one (initial) node to another (destination) node is the same with the distance to travel back from destination to initial, this problems known to the Traveling Salesman Problem (TSP), otherwise it call as an Asymmetric Traveling Salesman Problem (ATSP). The most recent optimization techniques is Symbiotic Organisms Search (SOS). This paper discuss how to hybrid the SOS algorithm with variable neighborhoods search (SOS-VNS) that can be applied to solve the ATSP problem. The proposed mechanism to add the variable neighborhoods search as a local search is to generate the better initial solution and then we modify the phase of parasites with adapting mechanism of mutation. After modification, the performance of the algorithm SOS-VNS is evaluated with several data sets and then the results is compared with the best known solution and some algorithm such PSO algorithm and SOS original algorithm. The SOS-VNS algorithm shows better results based on convergence, divergence and computing time.

Social Difficulties As Risk and Maintaining Factors in Anorexia Nervosa: A Mixed-Method Investigation

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Valentina Cardi

2018-02-01

Full Text Available Anorexia nervosa (AN is a serious psychiatric disorder characterized by severe restriction of energy intake and dangerously low body weight. Other domains of functioning are affected, including social functioning. Although difficulties within this domain have started to be acknowledged by the literature, some important gaps remain to be filled. Do social difficulties predate the onset of the illness? What difficulties in particular are relevant for the development and maintenance of the illness? The aim of this study is to combine the use of quantitative and qualitative methods to answer these questions. Ninety participants with lifetime AN (88 women and 2 men completed an online survey assessing memories of involuntary submissiveness within the family, fear of negative evaluation from others, perceived lack of social competence, feelings of social belonging, eating disorder symptoms, and work and social adjustment. Participants also answered three open questions regarding their experience of social relationships before and after the illness onset. The findings provided support for the hypothesized relationships between the study variables. Involuntary submissiveness and fear of negative evaluation predicted eating disorder symptoms and these associations were partially mediated by perceived lack of social competence. Two-thirds of the sample recalled early social difficulties before illness onset and recognized that these had played a role in the development of the illness. A larger proportion of participants stated that the eating disorder had affected their social relationships in a negative way. This study sheds some light on patients’ perspective on the predisposing and maintaining role that social difficulties play in AN and identifies key psychological variables that could be targeted in treatment.

Social Difficulties As Risk and Maintaining Factors in Anorexia Nervosa: A Mixed-Method Investigation.

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Cardi, Valentina; Mallorqui-Bague, Núria; Albano, Gaia; Monteleone, Alessio Maria; Fernandez-Aranda, Fernando; Treasure, Janet

2018-01-01

Anorexia nervosa (AN) is a serious psychiatric disorder characterized by severe restriction of energy intake and dangerously low body weight. Other domains of functioning are affected, including social functioning. Although difficulties within this domain have started to be acknowledged by the literature, some important gaps remain to be filled. Do social difficulties predate the onset of the illness? What difficulties in particular are relevant for the development and maintenance of the illness? The aim of this study is to combine the use of quantitative and qualitative methods to answer these questions. Ninety participants with lifetime AN (88 women and 2 men) completed an online survey assessing memories of involuntary submissiveness within the family, fear of negative evaluation from others, perceived lack of social competence, feelings of social belonging, eating disorder symptoms, and work and social adjustment. Participants also answered three open questions regarding their experience of social relationships before and after the illness onset. The findings provided support for the hypothesized relationships between the study variables. Involuntary submissiveness and fear of negative evaluation predicted eating disorder symptoms and these associations were partially mediated by perceived lack of social competence. Two-thirds of the sample recalled early social difficulties before illness onset and recognized that these had played a role in the development of the illness. A larger proportion of participants stated that the eating disorder had affected their social relationships in a negative way. This study sheds some light on patients' perspective on the predisposing and maintaining role that social difficulties play in AN and identifies key psychological variables that could be targeted in treatment.

Separation-Individuation Difficulties and Cognitive-Behavioral Indicators of Eating Disorders among College Women.

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Friedlander, Myrna L.; Siegel, Sheri M.

1990-01-01

Tested theoretical link between difficulties with separation-individuation and cognitive-behavioral indicators characteristic of anorexia nervosa and bulimia. Assessed 124 college women using three self-report measures. Results suggest strong relation between 2 sets of variables and support theoretical assertions about factors that contribute to…

Hydrology under difficulties

Energy Technology Data Exchange (ETDEWEB)

NONE

1964-08-15

An unusual hydrological investigation is being carried out in Kenya by IAEA, at Lake Chala, a volcanic crater with no visible inlet or outlet. The problem is to determine whether the lake has any connection with a number of springs near Taveta, some six miles distant: this relationship is important in assessing the possibility of expanding the Taveta irrigation scheme. Questions of water rights and utilization are involved, since the lake is situated on the Tanganyikan border. The method adopted is that of labelling the waters of the lake with small quantities of water containing radioactive hydrogen (tritium). There are some special features in this instance, one being the difficulty of access. The lake is entirely surrounded by steep cliffs. A track was cut by British Army engineers, and the boat and all supplies were taken down by this route. Another problem was presented by the depth of the lake, which amounts to 300 feet. It is necessary to ensure the regular mixing of the tritium throughout. This has been done by means of hundreds of plastic bottles, which were dropped from the boat at regular intervals as it made a series of carefully-plotted traverses. Each bottle had a weight attached, and was perforated by two small holes. By this means, as the bottle sank the contents were progressively released until it reached the bottom, thus ensuring an even diffusion of tritium throughout the lake.

Memory Abilities in Children with Mathematical Difficulties: Comorbid Language Difficulties Matter

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Reimann, Giselle; Gut, Janine; Frischknecht, Marie-Claire; Grob, Alexander

2013-01-01

The present study investigated cognitive abilities in children with difficulties in mathematics only (n = 48, M = 8 years and 5 months), combined mathematical and language difficulty (n = 27, M = 8 years and 1 month) and controls (n = 783, M = 7 years and 11 months). Cognitive abilities were measured with seven subtests, tapping visual perception,…

An Existential Perspective on Death Anxiety, Retirement, and Related Research Problems.

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Osborne, John W

2017-06-01

Aspects of existentialism relevant to existence and death anxiety (DA) are discussed. Included are the "thrownness" of existence, being-with-others, the motivational influence of inevitable death, the search for meaning, making the most of existence by taking responsibility for one's own life, and coping with existential isolation. The attempted separation of DA from object anxiety is a significant difficulty. The correlations among age, gender, and DA are variable. Personality and role-oriented problems in the transition to retirement are discussed along with Erikson's notion of "generativity" as an expression of the energy and purpose of mid-life. Furthermore, methodological and linguistic problems in DA research are considered. The article suggests qualitative methodologies as an interpersonal means of exploring DA within the contexts of psychotherapy and counselling.

Keldysh theory of strong field ionization: history, applications, difficulties and perspectives

International Nuclear Information System (INIS)

V Popruzhenko, S

2014-01-01

The history and current status of the Keldysh theory of strong field ionization are reviewed. The focus is on the fundamentals of the theory, its most important applications and those aspects which still raise difficulties and remain under discussion. The Keldysh theory is compared with other nonperturbative analytic methods of strong field atomic physics and its important generalizations are discussed. Among the difficulties, the gauge invariance problem, the tunneling time concept, the conditions of applicability and the application of the theory to ionization of systems more complex than atoms, including molecules and dielectrics, are considered. Possible prospects for the future development of the theory are also discussed. (review article)

Parametri, Variabili e altro: Un ripensamento su come questi concetti sono presentati in classe (Variable Parameters and Other Issues: A Review of How These Concepts Are Presented in Class).

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Chiarugi, Ivana; And Others

1995-01-01

This paper considers the problem of variables, in particular parameters, analyzes how these concepts are presented in textbooks, comments on paradigms of exercises in which parameters intervene, and points out difficulties encountered by students. Discusses results of teacher interviews concerning their dealing with parameters in class.…

Identifying predictors of physics item difficulty: A linear regression approach

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Mesic, Vanes; Muratovic, Hasnija

2011-06-01

Large-scale assessments of student achievement in physics are often approached with an intention to discriminate students based on the attained level of their physics competencies. Therefore, for purposes of test design, it is important that items display an acceptable discriminatory behavior. To that end, it is recommended to avoid extraordinary difficult and very easy items. Knowing the factors that influence physics item difficulty makes it possible to model the item difficulty even before the first pilot study is conducted. Thus, by identifying predictors of physics item difficulty, we can improve the test-design process. Furthermore, we get additional qualitative feedback regarding the basic aspects of student cognitive achievement in physics that are directly responsible for the obtained, quantitative test results. In this study, we conducted a secondary analysis of data that came from two large-scale assessments of student physics achievement at the end of compulsory education in Bosnia and Herzegovina. Foremost, we explored the concept of “physics competence” and performed a content analysis of 123 physics items that were included within the above-mentioned assessments. Thereafter, an item database was created. Items were described by variables which reflect some basic cognitive aspects of physics competence. For each of the assessments, Rasch item difficulties were calculated in separate analyses. In order to make the item difficulties from different assessments comparable, a virtual test equating procedure had to be implemented. Finally, a regression model of physics item difficulty was created. It has been shown that 61.2% of item difficulty variance can be explained by factors which reflect the automaticity, complexity, and modality of the knowledge structure that is relevant for generating the most probable correct solution, as well as by the divergence of required thinking and interference effects between intuitive and formal physics knowledge

Identifying predictors of physics item difficulty: A linear regression approach

Directory of Open Access Journals (Sweden)

Hasnija Muratovic

2011-06-01

Full Text Available Large-scale assessments of student achievement in physics are often approached with an intention to discriminate students based on the attained level of their physics competencies. Therefore, for purposes of test design, it is important that items display an acceptable discriminatory behavior. To that end, it is recommended to avoid extraordinary difficult and very easy items. Knowing the factors that influence physics item difficulty makes it possible to model the item difficulty even before the first pilot study is conducted. Thus, by identifying predictors of physics item difficulty, we can improve the test-design process. Furthermore, we get additional qualitative feedback regarding the basic aspects of student cognitive achievement in physics that are directly responsible for the obtained, quantitative test results. In this study, we conducted a secondary analysis of data that came from two large-scale assessments of student physics achievement at the end of compulsory education in Bosnia and Herzegovina. Foremost, we explored the concept of “physics competence” and performed a content analysis of 123 physics items that were included within the above-mentioned assessments. Thereafter, an item database was created. Items were described by variables which reflect some basic cognitive aspects of physics competence. For each of the assessments, Rasch item difficulties were calculated in separate analyses. In order to make the item difficulties from different assessments comparable, a virtual test equating procedure had to be implemented. Finally, a regression model of physics item difficulty was created. It has been shown that 61.2% of item difficulty variance can be explained by factors which reflect the automaticity, complexity, and modality of the knowledge structure that is relevant for generating the most probable correct solution, as well as by the divergence of required thinking and interference effects between intuitive and formal

Problems in quantum mechanics

CERN Document Server

Goldman, Iosif Ilich; Geilikman, B T

2006-01-01

This challenging book contains a comprehensive collection of problems in nonrelativistic quantum mechanics of varying degrees of difficulty. It features answers and completely worked-out solutions to each problem. Geared toward advanced undergraduates and graduate students, it provides an ideal adjunct to any textbook in quantum mechanics.

Differentiating Students with Mathematics Difficulty in College: Mathematics Disabilities vs. No Diagnosis

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McGlaughlin, Sean M.; Knoop, Andrew J.; Holliday, Gregory A.

2005-01-01

Difficulties with college algebra can be the gatekeeper for earning a degree. Students struggle with algebra for many reasons. The focus of study was to examine students struggling with entry-level algebra courses and differentiate between those who were identified as having a mathematics disability and those who were not. Variables related to…

The Patch-Levy-Based Bees Algorithm Applied to Dynamic Optimization Problems

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Wasim A. Hussein

2017-01-01

Full Text Available Many real-world optimization problems are actually of dynamic nature. These problems change over time in terms of the objective function, decision variables, constraints, and so forth. Therefore, it is very important to study the performance of a metaheuristic algorithm in dynamic environments to assess the robustness of the algorithm to deal with real-word problems. In addition, it is important to adapt the existing metaheuristic algorithms to perform well in dynamic environments. This paper investigates a recently proposed version of Bees Algorithm, which is called Patch-Levy-based Bees Algorithm (PLBA, on solving dynamic problems, and adapts it to deal with such problems. The performance of the PLBA is compared with other BA versions and other state-of-the-art algorithms on a set of dynamic multimodal benchmark problems of different degrees of difficulties. The results of the experiments show that PLBA achieves better results than the other BA variants. The obtained results also indicate that PLBA significantly outperforms some of the other state-of-the-art algorithms and is competitive with others.

Improved method for solving the neutron transport problem by discretization of space and energy variables

International Nuclear Information System (INIS)

Bosevski, T.

1971-01-01

The polynomial interpolation of neutron flux between the chosen space and energy variables enabled transformation of the integral transport equation into a system of linear equations with constant coefficients. Solutions of this system are the needed values of flux for chosen values of space and energy variables. The proposed improved method for solving the neutron transport problem including the mathematical formalism is simple and efficient since the number of needed input data is decreased both in treating the spatial and energy variables. Mathematical method based on this approach gives more stable solutions with significantly decreased probability of numerical errors. Computer code based on the proposed method was used for calculations of one heavy water and one light water reactor cell, and the results were compared to results of other very precise calculations. The proposed method was better concerning convergence rate, decreased computing time and needed computer memory. Discretization of variables enabled direct comparison of theoretical and experimental results

A Longitudinal Study of Financial Difficulties and Mental Health in a National Sample of British Undergraduate Students.

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Richardson, Thomas; Elliott, Peter; Roberts, Ron; Jansen, Megan

2017-04-01

Previous research has shown a relationship between financial difficulties and poor mental health in students, but most research is cross-sectional. To examine longitudinal relationships over time between financial variables and mental health in students. A national sample of 454 first year British undergraduate students completed measures of mental health and financial variables at up to four time points across a year. Cross-sectional relationships were found between poorer mental health and female gender, having a disability and non-white ethnicity. Greater financial difficulties predicted greater depression and stress cross-sectionally, and also predicted poorer anxiety, global mental health and alcohol dependence over time. Depression worsened over time for those who had considered abandoning studies or not coming to university for financial reasons, and there were effects for how students viewed their student loan. Anxiety and alcohol dependence also predicted worsening financial situation suggesting a bi-directional relationship. Financial difficulties appear to lead to poor mental health in students with the possibility of a vicious cycle occurring.

Kosovo’s Experience for Children with Feeding Difficulties after Cardiac Surgery for Congenital Heart Defect

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Bejiqi, Ramush; Retkoceri, Ragip; Bejiqi, Hana; Maloku, Arlinda; Vuçiterna, Armend; Zeka, Naim; Gerguri, Abdurrahim; Bejiqi, Rinor

2017-01-01

BACKGROUND: A feeding disorder in infancy and during childhood is a complex condition involving different symptoms such as food refusal and faddiest, both leading to a decreased food intake. AIM: We aimed to assess the prevalence and predictor factors of feeding difficulties in children who underwent cardiac open heart surgery in neonatal period and infancy. We address selected nutritional and caloric requirements for children after cardiac surgery and explore nutritional interdependence with other system functions. METHODS: This was a retrospective study in a tertiary referral hospital, and prior approval from the institutional ethics committee was obtained. Information for 78 children (42 male and 36 female) was taken from patients charts. Data were analysed with descriptive statistics and logistic regression. RESULTS: From a cohort of analysed children with feeding problems we have occurred in 23% of such cases. At the time of the study, refusal to eat or poor appetite was reported as a significant problem in 19 children and subnormal height and weight were recorded in 11 children. Early neonatal intervention and reoperation were identified as risk factors for latter feeding difficulties or inadequate intake. Children with feeding problems also tended to eat less than children without feeding problems. There was a trend towards more feeding problems in patients with chromosomal abnormalities or other associated anomalies. CONCLUSION: Feeding disorder is often and a frequent long-term sequel in children after neonatal or early infancy heart surgery. Patients with chromosomal and associated anomalies who underwent multiple cardiac surgeries are at risk of developing feeding difficulties. PMID:29362619

The association of sleep difficulties with health-related quality of life among patients with fibromyalgia.

Science.gov (United States)

Wagner, Jan-Samuel; DiBonaventura, Marco D; Chandran, Arthi B; Cappelleri, Joseph C

2012-10-17

Difficulty sleeping is common among patients with fibromyalgia (FM); however, its impact on health-related quality of life (HRQoL) is not well understood. The aim of the current study was to assess the burden of sleep difficulty symptoms on HRQoL among patients with FM. The current study included data from the 2009 National Health and Wellness Survey (N=75,000), which is a cross-sectional, Internet-based survey representative of the adult US population. The prevalence of sleep difficulty symptoms among patients with FM (n=2,196) were compared with matched controls (n=2,194), identified using propensity-score matching. Additionally, the relationship between the number of sleep difficulty symptoms (none, one, or two or more) and HRQoL (using the SF-12v2) was assessed using regression modeling, controlling for demographic and health history variables. Of the 2,196 patients with FM, 11.2% reported no sleep difficulty symptoms, 25.7% reported one sleep difficulty symptom, and 63.05% reported two or more sleep difficulty symptoms. The prevalence of sleep difficulty symptoms was significantly higher than matched controls. Patients with one and two sleep difficulty symptoms both reported significantly worse HRQoL summary and domain scores relative to those with no sleep difficulty symptoms (all p<.05). Further, the relationship between sleep difficulty symptoms and HRQoL was significantly different between those with FM than matched controls, suggesting a uniqueness of the burden of sleep difficulties within the FM population. Among the FM population, sleep difficulty symptoms were independently associated with clinically-meaningful decrements in mental and physical HRQoL. These results suggest that greater emphasis in the treatment of sleep difficulty symptoms among the FM population may be warranted.

Influence of burnout and sleep difficulties on the quality of life among medical students.

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Pagnin, Daniel; de Queiroz, Valéria

2015-01-01

This study assessed the influence of burnout dimensions and sleep difficulties on the quality of life among preclinical-phase medical school students. Data were collected from 193 students through their completion of the World Health Organization Quality of Life Instrument, the Maslach Burnout Inventory-Student Survey, the Mini-Sleep Questionnaire, the Social Readjustment Rating Scale, and the Beck Depression Inventory. This survey performed hierarchical multiple regressions to quantify the effects of emotional exhaustion, cynicism, academic efficacy, and sleep difficulties on the physical, psychological, social, and environmental components of an individual's quality of life. The influence of confounding variables, such as gender, stress load, and depressive symptoms, were controlled in the statistical analyses. Physical health decreased when emotional exhaustion and sleep difficulties increased. Psychological well-being also decreased when cynicism and sleep difficulties increased. Burnout and sleep difficulties together explained 22 and 21 % of the variance in the physical and psychological well-being, respectively. On the other hand, physical health, psychological well-being, and social relationships increased when the sense of academic efficacy increased. Physical and psychological well-being are negatively associated with emotional exhaustion, cynicism, and sleep difficulties in students in the early phase of medical school. To improve the quality of life of these students, a significant effort should be directed towards burnout and sleep difficulties.

Research on Difficulty in Indonesia Students Learning Chinese Language

Directory of Open Access Journals (Sweden)

Lydia Anggreani

2013-05-01

Full Text Available Chinese has become the world’s second language. Each language has its own law, as is the Chinese. Indonesian students have difficulty in learning Chinese which are are not surprising. Every language has various characteristics, so do Chinese and Bahasa Indonesia. Article analyzes difficulties to learn Chinese, especially for Indonesian students, those are tone, grammar, sounds of “er hua” such as Alice retroflex. The respondents are 100 Indonesian students who are randomly selected for testing samples analyzed. Since there is no tone in Bahasa Indonesia, it makes a lot of Indonesian students in the learning process often appear in Chinese foreign accent phenomenon. This article expects to explore the problem by studying the formation of the causes and solutions. Indonesian students learning Chinese was designed to provide some teaching and learning strategies.

MANAGEMENT AND CHALLENGES OF BRAZILIAN AIRPORT INFRASTRUCTURE: OPERATIONAL DIFFICULTIES FOR LARGE EVENTS

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Jorge Luiz Knupp Rodrigues

2014-09-01

Full Text Available This work aims to present, discuss and reflect on the solutions and consequences for the achievement of major events in Brazil in relation to the main operational difficulties in its current airport infrastructure. Operational difficulties refers to various factors that hinder or prevent the development of airport activities, such as aircraft delays, flight cancellations and customer discomfort. Therefore, this article seeks to think over the structure of the facilities, the lack of investment, the deadlines for solutions and other problems that need definite solution so that they will not occur again. In order to reach our objectives, we use data from literature and documentary analysis of statistical data. We present the main difficulties of operational modal Brazilian air transportation, the options for solution and the importance of actions for social, technical and financial development in Brazil.

Verbal Problem-Solving Difficulties in Autism Spectrum Disorders and Atypical Language Development

Science.gov (United States)

Alderson-Day, Ben

2018-01-01

Children with autism spectrum disorders (ASDs) adopt less efficient strategies than typically developing (TD) peers on the Twenty Questions Task (TQT), a measure of verbal problem-solving skills. Although problems with the TQT are typically associated with executive dysfunction, they have also been reported in children who are deaf, suggesting a role for atypical language development. To test the contribution of language history to ASD problem solving, TQT performance was compared in children with high-functioning autism (HFA), children with Asperger syndrome (AS) and TD children. The HFA group used significantly less efficient strategies than both AS and TD children. No group differences were evident on tests of question understanding, planning or verbal fluency. Potential explanations for differences in verbal problem-solving skill are discussed with reference to the development of inner speech and use of visual strategies in ASD. PMID:25346354

Stimulus variability and the phonetic relevance hypothesis: effects of variability in speaking style, fundamental frequency, and speaking rate on spoken word identification.

Science.gov (United States)

Sommers, Mitchell S; Barcroft, Joe

2006-04-01

Three experiments were conducted to examine the effects of trial-to-trial variations in speaking style, fundamental frequency, and speaking rate on identification of spoken words. In addition, the experiments investigated whether any effects of stimulus variability would be modulated by phonetic confusability (i.e., lexical difficulty). In Experiment 1, trial-to-trial variations in speaking style reduced the overall identification performance compared with conditions containing no speaking-style variability. In addition, the effects of variability were greater for phonetically confusable words than for phonetically distinct words. In Experiment 2, variations in fundamental frequency were found to have no significant effects on spoken word identification and did not interact with lexical difficulty. In Experiment 3, two different methods for varying speaking rate were found to have equivalent negative effects on spoken word recognition and similar interactions with lexical difficulty. Overall, the findings are consistent with a phonetic-relevance hypothesis, in which accommodating sources of acoustic-phonetic variability that affect phonetically relevant properties of speech signals can impair spoken word identification. In contrast, variability in parameters of the speech signal that do not affect phonetically relevant properties are not expected to affect overall identification performance. Implications of these findings for the nature and development of lexical representations are discussed.

Variable neighborhood search to solve the vehicle routing problem for hazardous materials transportation.

Science.gov (United States)

Bula, Gustavo Alfredo; Prodhon, Caroline; Gonzalez, Fabio Augusto; Afsar, H Murat; Velasco, Nubia

2017-02-15

This work focuses on the Heterogeneous Fleet Vehicle Routing problem (HFVRP) in the context of hazardous materials (HazMat) transportation. The objective is to determine a set of routes that minimizes the total expected routing risk. This is a nonlinear function, and it depends on the vehicle load and the population exposed when an incident occurs. Thus, a piecewise linear approximation is used to estimate it. For solving the problem, a variant of the Variable Neighborhood Search (VNS) algorithm is employed. To improve its performance, a post-optimization procedure is implemented via a Set Partitioning (SP) problem. The SP is solved on a pool of routes obtained from executions of the local search procedure embedded on the VNS. The algorithm is tested on two sets of HFVRP instances based on literature with up to 100 nodes, these instances are modified to include vehicle and arc risk parameters. The results are competitive in terms of computational efficiency and quality attested by a comparison with Mixed Integer Linear Programming (MILP) previously proposed. Copyright © 2016 Elsevier B.V. All rights reserved.

Diagnosing companies in financial difficulty based on the auditor’s report

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Robert Zenzerović

2016-04-01

Full Text Available The approach used in this paper expands on existing research that focuses on devising prediction models for companies experiencing financial difficulties and which in turn serves as a criteria-based diagnosis tool for distinguishing healthy companies from those facing seriously financial difficulties. It draws on auditors’ reports on company financial statements that emphasize a company’s ability to continue as a going concern as the main criterion used to distinguish companies experiencing financial difficulties from companies that are not. Two closely-related hypotheses were tested in this paper. First, the authors tested the hypothesis that an auditor’s report accompanied by an explanatory paragraph pointing out issues associated with the going concern assumption is the proper criterion for differentiating companies experiencing financial difficulties from those that are not. Second, the central assumption that is tested relates to a combination of financial ratios whereby authors presume that an appropriate combination of financial ratios is a good analytical tool for distinguishing companies experiencing serious financial difficulties from those that are not. Research results conducted among 191 companies listed on the Zagreb Stock Exchange confirm both hypotheses. The LRA model – a diagnosis tool for identifying companies with financial problems, was also derived using logistic regression analysis. The statistical adequacy and quality of the model was tested using measures like Nagelkerke R2, type 1 and type 2 errors that appear when calculating the classification ability of the model. All measures indicated that model was statistically sufficient and validated its use as a diagnosis tool in recognizing the companies facing financial difficulties.

Verbal problem-solving difficulties in autism spectrum disorders and atypical language development.

Science.gov (United States)

Alderson-Day, Ben

2014-12-01

Children with autism spectrum disorders (ASDs) adopt less efficient strategies than typically developing (TD) peers on the Twenty Questions Task (TQT), a measure of verbal problem-solving skills. Although problems with the TQT are typically associated with executive dysfunction, they have also been reported in children who are deaf, suggesting a role for atypical language development. To test the contribution of language history to ASD problem solving, TQT performance was compared in children with high-functioning autism (HFA), children with Asperger syndrome (AS) and TD children. The HFA group used significantly less efficient strategies than both AS and TD children. No group differences were evident on tests of question understanding, planning or verbal fluency. Potential explanations for differences in verbal problem-solving skill are discussed with reference to the development of inner speech and use of visual strategies in ASD. © 2014 International Society for Autism Research, Wiley Periodicals, Inc.

Comparison Between Two Methods for Estimating the Vertical Scale of Fluctuation for Modeling Random Geotechnical Problems

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Pieczyńska-Kozłowska, Joanna M.

2015-12-01

The design process in geotechnical engineering requires the most accurate mapping of soil. The difficulty lies in the spatial variability of soil parameters, which has been a site of investigation of many researches for many years. This study analyses the soil-modeling problem by suggesting two effective methods of acquiring information for modeling that consists of variability from cone penetration test (CPT). The first method has been used in geotechnical engineering, but the second one has not been associated with geotechnics so far. Both methods are applied to a case study in which the parameters of changes are estimated. The knowledge of the variability of parameters allows in a long term more effective estimation, for example, bearing capacity probability of failure.

Using a Multidimensional Measure of Resilience to Explain Life Satisfaction and Academic Achievement of Adults with Reading Difficulties

Science.gov (United States)

Stack-Cutler, Holly L.; Parrila, Rauno K.; Torppa, Minna

2015-01-01

We assessed the impact of intrapersonal and interpersonal resilience, persistence, and number of difficulties in addition to reading problems on life satisfaction (general, social, and self) and academic achievement. A total of 120 adults with reading difficulties who either were completing a university degree or were recent graduates responded to…

Experience in a Climate Microworld: Influence of Surface and Structure Learning, Problem Difficulty, and Decision Aids in Reducing Stock-Flow Misconceptions

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Medha Kumar

2018-03-01

Full Text Available Research shows that people’s wait-and-see preferences for actions against climate change are a result of several factors, including cognitive misconceptions. The use of simulation tools could help reduce these misconceptions concerning Earth’s climate. However, it is still unclear whether the learning in these tools is of the problem’s surface features (dimensions of emissions and absorptions and cover-story used or of the problem’s structural features (how emissions and absorptions cause a change in CO2 concentration under different CO2 concentration scenarios. Also, little is known on how problem’s difficulty in these tools (the shape of CO2 concentration trajectory, as well as the use of these tools as a decision aid influences performance. The primary objective of this paper was to investigate how learning about Earth’s climate via simulation tools is influenced by problem’s surface and structural features, problem’s difficulty, and decision aids. In experiment 1, we tested the influence of problem’s surface and structural features in a simulation called Dynamic Climate Change Simulator (DCCS on subsequent performance in a paper-and-pencil Climate Stabilization (CS task (N = 100 across four between-subject conditions. In experiment 2, we tested the effects of problem’s difficulty in DCCS on subsequent performance in the CS task (N = 90 across three between-subject conditions. In experiment 3, we tested the influence of DCCS as a decision aid on subsequent performance in the CS task (N = 60 across two between-subject conditions. Results revealed a significant reduction in people’s misconceptions in the CS task after performing in DCCS compared to when performing in CS task in the absence of DCCS. The decrease in misconceptions in the CS task was similar for both problems’ surface and structural features, showing both structure and surface learning in DCCS. However, the proportion of misconceptions was similar across

Regulatory difficulties in a developing country

International Nuclear Information System (INIS)

Jacobs, W.R. Jr.

1978-01-01

The regulatory agency assigned the task of regulating the initial entry into the field of nuclear power generation by a developing country has a very difficult job. Based on the authors' experience during the start-up and initial operation of Ko-Ri Unit I, the first power reactor in the Republic of Korea, observations on regulatory difficulties and recommendations for improved regulatory effectiveness are offered. The problem areas can be loosely grouped into three general categories: (1) Lack of adequate technical knowledge which is the basis for all effective regulation; (2) Difficulties with understanding and utilization of the required regulatory documentation; (3) Failure to establish the proper regulatory environment. Examples are cited from actual experience during the Ko-Ri Unit I start-up to demonstrate the impact that regulatory activities can have on a plant construction and testing programme. The problems encountered are not unique to developing countries but also exist in the United States of America. Recommendations are offered which should be beneficial to either newly formed regulatory agencies or agencies wishing to improve their abilities and effectiveness. These include: (1) Additional training of regulatory inspectors in plant operations; (2) Additional experience gained by participation in regulatory activities in other countries; (3) Increased attention given to regulatory documents, especially plant technical specifications; (4) Establishment of formal lines of communication between the utility and the regulatory agency; (5) Clear definition of regulatory responsibilities to avoid areas of overlapping jurisdiction; (6) Active participation by the regulatory staff very early in the project. It is hoped that these and other recommendations offered will greatly improve regulatory effectiveness and at the same time demonstrate that when the decision is made to 'go nuclear', a strong commitment must be made to develop and support a technically

Young people at risk of psychosis: a user-led exploration of interpersonal relationships and communication of psychological difficulties.

Science.gov (United States)

Byrne, Rory; Morrison, Anthony P

2010-05-01

The aim of the present study was to qualitatively explore experiences and perceptions of interpersonal relationships and interpersonal communication among young people at risk of psychosis. Semi-structured interviews were conducted using a qualitative grounded theory approach. Participants had entered into a service providing psychological interventions for young people assessed to be at a high risk of developing psychosis (Northwest UK). Our sample comprised one female and seven male participants (n = 8), ranging in age from 16 to 28 years, with a mean age of 22.4 years. Analyses identified three central themes: difficulty with interpersonal relationships and reduced opportunities for helpful communication, difficulty talking to others about psychological problems, and experiences of talking to others about psychological problems. Individuals at risk of psychosis may have experienced significant difficulties with interpersonal relationships. Such difficulties may contribute directly to the development of unusual psychological experiences, and to an inability or reluctance to communicate these to others. In addition, commonly held stigmatizing ideas associated with unusual psychological experiences may contribute to a fear among at-risk individuals that they are 'going mad', and this may lead to concealment of their difficulties, and to delayed help-seeking. For at-risk individuals, helpful communication of psychological distress offers significant benefits, including improved psychological and emotional well-being and reduced risk of psychosis. Thus, while concealment of distress may directly impact on the development of unusual psychological difficulties, communication of such difficulties may be central to recovery.

Moving from graduation to post-graduation in portuguese universities : changing literacy practices, facing new difficulties

OpenAIRE

Carvalho, José António Brandão

2012-01-01

In this article we analyse Portuguese postgraduate students’ problems and difficulties when performing written tasks in the context of postgraduate programmes. The data presented are the result of a study based on two different data collection procedures: a) the analysis of students’ written work, organised in a portfolio; b) a questionnaire focussing on the difficulties encountered when performing different tasks involving writing: note-taking; planning a text; writing and editing a text (a ...

On the use of antithetic variates in particle transport problems

International Nuclear Information System (INIS)

Milgram, M.S.

2001-01-01

The possible use of antithetic variates as a method of variance reduction in particle transport problems is investigated, by performing some numerical experiments. It is found that if variance reduction is not very carefully defined, it is possible, with antithetic variates, to spuriously detect reduction, or not detect true reduction. Once such subtleties are overcome, it is shown that antithetic variates can reduce variance in multidimensional integration up to a point. The phenomenon of spontaneous correlation is defined and identified as the cause of failure. The surprising result that it sometimes pays to track non-contributing particle histories is demonstrated by means of a zero variance integration analogue. The principles developed in the investigation of multi-variable integration are then employed in a simple calculation of energy deposition using the EGS4 computer code. Promising results are obtained for the total energy deposition problem, but the depth/dose problem remains unsolved. Possible means of overcoming the difficulties are suggested

Development and Validation of a Rubric for Diagnosing Students' Experimental Design Knowledge and Difficulties.

Science.gov (United States)

Dasgupta, Annwesa P; Anderson, Trevor R; Pelaez, Nancy

2014-01-01

It is essential to teach students about experimental design, as this facilitates their deeper understanding of how most biological knowledge was generated and gives them tools to perform their own investigations. Despite the importance of this area, surprisingly little is known about what students actually learn from designing biological experiments. In this paper, we describe a rubric for experimental design (RED) that can be used to measure knowledge of and diagnose difficulties with experimental design. The development and validation of the RED was informed by a literature review and empirical analysis of undergraduate biology students' responses to three published assessments. Five areas of difficulty with experimental design were identified: the variable properties of an experimental subject; the manipulated variables; measurement of outcomes; accounting for variability; and the scope of inference appropriate for experimental findings. Our findings revealed that some difficulties, documented some 50 yr ago, still exist among our undergraduate students, while others remain poorly investigated. The RED shows great promise for diagnosing students' experimental design knowledge in lecture settings, laboratory courses, research internships, and course-based undergraduate research experiences. It also shows potential for guiding the development and selection of assessment and instructional activities that foster experimental design. © 2014 A. P. Dasgupta et al. CBE—Life Sciences Education © 2014 The American Society for Cell Biology. This article is distributed by The American Society for Cell Biology under license from the author(s). It is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

Validity of a Protocol for Adult Self-Report of Dyslexia and Related Difficulties

Science.gov (United States)

Snowling, Margaret; Dawes, Piers; Nash, Hannah; Hulme, Charles

2012-01-01

Background There is an increased prevalence of reading and related difficulties in children of dyslexic parents. In order to understand the causes of these difficulties, it is important to quantify the risk factors passed from parents to their offspring. Method 417 adults completed a protocol comprising a 15-item questionnaire rating reading and related skills and a scale assessing ADHD symptoms; 344 completed reading, nonword reading and spelling tests. Results A confirmatory factor analysis with four factors (Reading, Word Finding, Attention and Hyperactivity) provided a reasonable fit to the data. The Reading Factor showed robust correlations with measured literacy skills. Adults who reported as dyslexic, or rated their reading difficulties as more severe, gained lower scores on objective measures of literacy skills. Although the sensitivity of the new scale was acceptable, it tended to miss some cases of low literacy. Conclusions Self-report scales of reading and of attention difficulties are useful for identifying adults with reading and attention difficulties which may confer risks on their children of related problems. It is important for research following children at family risk of dyslexia to be aware of these effects. Copyright © 2012 John Wiley & Sons, Ltd. PMID:22271419

Progression paths in children's problem solving: The influence of dynamic testing, initial variability, and working memory.

Science.gov (United States)

Resing, Wilma C M; Bakker, Merel; Pronk, Christine M E; Elliott, Julian G

2017-01-01

The current study investigated developmental trajectories of analogical reasoning performance of 104 7- and 8-year-old children. We employed a microgenetic research method and multilevel analysis to examine the influence of several background variables and experimental treatment on the children's developmental trajectories. Our participants were divided into two treatment groups: repeated practice alone and repeated practice with training. Each child received an initial working memory assessment and was subsequently asked to solve figural analogies on each of several sessions. We examined children's analogical problem-solving behavior and their subsequent verbal accounts of their employed solving processes. We also investigated the influence of verbal and visual-spatial working memory capacity and initial variability in strategy use on analogical reasoning development. Results indicated that children in both treatment groups improved but that gains were greater for those who had received training. Training also reduced the influence of children's initial variability in the use of analogical strategies with the degree of improvement in reasoning largely unrelated to working memory capacity. Findings from this study demonstrate the value of a microgenetic research method and the use of multilevel analysis to examine inter- and intra-individual change in problem-solving processes. Copyright © 2016 Elsevier Inc. All rights reserved.

Association between workaholism and sleep problems among hospital nurses.

Science.gov (United States)

Kubota, Kazumi; Shimazu, Akihito; Kawakami, Norito; Takahashi, Masaya; Nakata, Akinori; Schaufeli, Wilmar B

2010-01-01

The present study examined the association between workaholism, the tendency to work excessively hard in a compulsive fashion, and sleep problems among Japanese nurses. A cross-sectional survey was conducted among 600 nurses from 2 university hospitals in Japan using a self-reported questionnaire on workaholism, sleep, job-related variables (i.e., job demands, job control, and worksite support), and demographic variables. A total of 394 nurses returned the questionnaire (response rate=65.7%) and complete data from 312 female nurses were used for analyses (final coverage rate=52.0%). Workaholics, as measured using the Japanese version of the Dutch Workaholism Scale, were defined as those having high scores on both the "work excessively" and "work compulsively" subscales. Logistic regression analyses revealed that workaholics had higher risks for sleep problems in terms of subjective sleep insufficiency, excessive daytime sleepiness at work, difficulty awakening in the morning, and feeling tired when waking up in the morning (odds ratios [OR] of 4.40, 3.18, 3.48, and 4.61, respectively, p<0.05). These remained significant even after adjusting for demographic and job-related variables (OR 3.41, 5.36, 2.56, and 2.77, respectively). However, no significant associations were found between workaholism and insomnia symptoms. These results suggest that workaholic nurses had higher risks for impaired awakening, insufficient sleep, and workplace sleepiness.

Improving mathematical problem solving : A computerized approach

NARCIS (Netherlands)

Harskamp, EG; Suhre, CJM

Mathematics teachers often experience difficulties in teaching students to become skilled problem solvers. This paper evaluates the effectiveness of two interactive computer programs for high school mathematics problem solving. Both programs present students with problems accompanied by instruction

Secondary Education Students' Difficulties in Algorithmic Problems with Arrays: An Analysis Using the SOLO Taxonomy

Science.gov (United States)

Vrachnos, Euripides; Jimoyiannis, Athanassios

2017-01-01

Developing students' algorithmic and computational thinking is currently a major objective for primary and secondary education in many countries around the globe. Literature suggests that students face at various difficulties in programming processes, because of their mental models about basic programming constructs. Arrays constitute the first…

Mediators of Change in a Parent Training Program for Early ADHD Difficulties

DEFF Research Database (Denmark)

Rimestad, Marie Louise; O'Toole, Mia Skytte; Hougaard, Esben

2017-01-01

OBJECTIVE: The aim was to explore mediators of change in parent training (PT) for 3- to 8-year-old children with ADHD difficulties. METHOD: Parents of 64 children received PT with Incredible Years® and assessed child ADHD symptoms and conduct problems and their parenting strategies, parental self...

Teacher Ratings of Children's Behavior Problems and Functional Impairment Across Gender and Ethnicity : Construct Equivalence of the Strengths and Difficulties Questionnaire

NARCIS (Netherlands)

Zwirs, Barbara; Burger, Huibert; Schulpen, Tom; Vermulst, A. A.; HiraSing, R. A.; Buitelaar, Jan

The present study examined construct equivalence of the teacher Strengths and Difficulties Questionnaire and compared mean scores in an ethnically diverse sample of children living in the Netherlands. Elementary schoolteachers completed the Strengths and Difficulties Questionnaire for 2,185 children

Teacher ratings of children's behavior problems and functional impairment across gender and ethnicity: construct equivalence of the strengths and difficulties questionnaire

NARCIS (Netherlands)

Zwirs, B.; Burger, H.; Schulpen, T.; Vermulst, A.A.; Hira Sing, R.A.; Buitelaar, J.

2011-01-01

The present study examined construct equivalence of the teacher Strengths and Difficulties Questionnaire and compared mean scores in an ethnically diverse sample of children living in the Netherlands. Elementary schoolteachers completed the Strengths and Difficulties Questionnaire for 2,185 children

Effect of age, sex and level of surgical difficulty on inflammatory complications after third molar surgery.

Science.gov (United States)

Osunde, Otasowie D; Saheeb, Birch D

2015-03-01

Patients' factors such as age and sex and surgical variables such as level of difficulty have been linked with surgical outcome in third molar surgery. The aim of this study was to determine the effect of these variables on inflammatory complications in patients undergoing third molar surgery. Patients referred to our institution for surgical extraction of their impacted lower third molar between January 2007 and December 2008 were the subjects of the study. Patients' demographics as well as types of impaction, indication and level of difficulty based on Pederson criteria were obtained. Post operative pain, swelling and mouth opening limitation were evaluated at day 1, day 2, day 3, day 5 and 1 week after the surgery and analyzed. A p value of less than 0.05 was considered significant. A total of 150 patients aged 16-38 years (25.9 ± 4.47) met the inclusion criteria. Male accounted for 66 (44.0 %) while females were 84 (56.0 %), giving male to female ratio of 1:1.3. Age, sex and difficulty index had no effect on pain and trismus throughout the periods of postoperative evaluation (p > 0.05). Postoperative swelling was not affected by gender but patients above 25 years who had high scores of difficulty index had more facial swelling. The results of this study shows that age, gender and the level of surgical difficulty have no effect on pain and mouth opening limitation after third molar surgery.

Research on problem solving skills of orienteering athletes in terms of some variables

Directory of Open Access Journals (Sweden)

Eroğlu Başak

2016-01-01

Full Text Available The aim of this study is to examine the problem solving skills of orienteering athletes in terms of different variables. 157 male and 43 female orienteering athletes, making a total of 200 athletes that joined the 3rd Level of Turkey Championship in 2015 have participated in this study which is in a survey model. The data collection tools were the Problem Solving Inventory and Personal Information Form that were formed by Heppner & Peterson (1982 and adapted into Turkish by Şahin, Şahin & Heppner (1993. In the data analysis, descriptive statics, anova, t test and Tukey test have been utilized. In the line with the findings, it has been determined that the difference between the total mean values (85.55+20.45 that the orienteering athletes got from the problem solving inventory and their age, marital status, sports age, the years of practice in orienteering sports, and the status of being national player is significant (p<0.05. It has been found that male orienteering athletes perform higher evaluating approach compared to the female athletes, and that as the age levels increase, the problem solving skill is affected more positively. Furthermore, it has been determined that the perceptions of the participants that have more experience and sports age in orienteering sports and that do orienteering sports at a national level are more positive in the matter of problem solving skills.

Some types of difficulty encountered during the simulation of heat exchangers (1961)

International Nuclear Information System (INIS)

Bettembourg, D.

1961-01-01

After recalling that the simulation of exchangers poses problems which are often difficult to solve, the author points out that these problems appear first of all when the physical phenomena are described in terms of equations. They appear also during the solving of the equations since expressions which are more and more complex can give rise to unstable electronic structures. These difficulties are developed during the analysis of various types of exchangers and in each case the solutions chosen are given. (author) [fr

DIFFICULTIES OF SPEAKING THAT ARE ENCOUNTERED BY ENGLISH LANGUAGE STUDENTS AT AL MARGEB UNIVERSITY

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Mohamed Dalem

2017-11-01

Full Text Available The aim of this paper is to explore the speaking difficulties encountered by English language students at Al Margeb University, and to discover the causes of such difficulties. Speaking English has been a vital importance in international communication. Speaking fluent English is a common problem among the nonnative speakers. The second language learners have gone through a variety of cases to learn how to speak not only correct grammar and using the right vocabulary but with correct accent and pronunciation. Many obstacles, therefore, have been known as the predictors of such a problem among the language learners.  According to the review of literature, appropriate speaking instruction was found to be the learners' priority and a field in which they need more attention. In this paper the writer highlight the speaking difficulties encountered by English language students at Al Margeb University, which are considered to be the most urgent for every teacher, such as fear of mistakes, shyness, anxiety, lack of confidence and lack of motivation. This paper can be useful to teachers to consider their language learners' speaking needs in English language teaching and learning context.

Reduced heart rate variability in pet dogs affected by anxiety-related behaviour problems.

Science.gov (United States)

Wormald, Dennis; Lawrence, Andrew J; Carter, Gabrielle; Fisher, Andrew D

2017-01-01

We present here the first evidence of correlation between canine anxiety-related behavioural problems and heart rate variability (HRV). HRV is known to be related to a range of mental disorders in humans; however this has not been explored in dogs. Behavioural problems in dogs can result in suffering, property destruction and human injury. Dog behaviour problems were assessed by owner questionnaire and the extreme high and low scoring dogs were recruited into either affected (n=10) or unaffected (n=20) groups. HRV was assessed in dogs at their homes, while being held in lateral recumbency for 5min using manual restraint. Salivary cortisol samples were taken before and after HRV testing. Dogs were assessed as either being reactive to the procedure (barking, growling, struggling or shaking) or unreactive. There was no effect of reactivity or behaviour problems on salivary cortisol levels at baseline or in response to the treatment. There was a significant effect of reactivity on HR (F 1,26 =5.54; P=0.026), and no effect of behaviour problems (F 1,26 =1.07; P=0.311). There was no effect of reactivity on any of the HRV measures. The presence of behaviour problems had a significant effect on a range of measures of HRV, with unaffected dogs having higher standard deviation of RR intervals (F 1,26 =6.39; P=0.018), higher high frequency spectrum (F 1,26 =5.23; P=0.031) and higher low frequency spectrum (F 1,26 =9.25; P=0.005) power. There was no effect of behaviour problems on very low frequency spectrum power (F 1,26 =1.40; P=0.248). Together these results provide evidence for a fundamental physiological difference between dogs affected or unaffected with behaviour problems. This study provides evidence for further investigation into the role of HRV in the pathophysiology of canine anxiety-related behaviour problems. Copyright © 2016. Published by Elsevier Inc.

Integer linear models with a polynomial number of variables and constraints for some classical combinatorial optimization problems

Directory of Open Access Journals (Sweden)

Nelson Maculan

2003-01-01

Full Text Available We present integer linear models with a polynomial number of variables and constraints for combinatorial optimization problems in graphs: optimum elementary cycles, optimum elementary paths and optimum tree problems.Apresentamos modelos lineares inteiros com um número polinomial de variáveis e restrições para problemas de otimização combinatória em grafos: ciclos elementares ótimos, caminhos elementares ótimos e problemas em árvores ótimas.

Time Processing Impairments in Preschoolers at Risk of Developing Difficulties in Mathematics

Science.gov (United States)

Tobia, Valentina; Rinaldi, Luca; Marzocchi, Gian Marco

2018-01-01

The occurrence of time processing problems in individuals with Development Dyscalculia (DD) has favored the view of a general magnitude system devoted to both numerical and temporal information. Yet, this scenario has been partially challenged by studies indicating that time difficulties can be attributed to poor calculation or counting skills,…

An Investigation of Difficulties Experienced by Students Developing Unified Modelling Language (UML) Class and Sequence Diagrams

Science.gov (United States)

Sien, Ven Yu

2011-01-01

Object-oriented analysis and design (OOAD) is not an easy subject to learn. There are many challenges confronting students when studying OOAD. Students have particular difficulty abstracting real-world problems within the context of OOAD. They are unable to effectively build object-oriented (OO) models from the problem domain because they…

Using an isomorphic problem pair to learn introductory physics: Transferring from a two-step problem to a three-step problem

Directory of Open Access Journals (Sweden)

Shih-Yin Lin

2013-10-01

Full Text Available In this study, we examine introductory physics students’ ability to perform analogical reasoning between two isomorphic problems which employ the same underlying physics principles but have different surface features. 382 students from a calculus-based and an algebra-based introductory physics course were administered a quiz in the recitation in which they had to learn from a solved problem provided and take advantage of what they learned from it to solve another isomorphic problem (which we call the quiz problem. The solved problem provided has two subproblems while the quiz problem has three subproblems, which is known from previous research to be challenging for introductory students. In addition to the solved problem, students also received extra scaffolding supports that were intended to help them discern and exploit the underlying similarities of the isomorphic solved and quiz problems. The data analysis suggests that students had great difficulty in transferring what they learned from a two-step problem to a three-step problem. Although most students were able to learn from the solved problem to some extent with the scaffolding provided and invoke the relevant principles in the quiz problem, they were not necessarily able to apply the principles correctly. We also conducted think-aloud interviews with six introductory students in order to understand in depth the difficulties they had and explore strategies to provide better scaffolding. The interviews suggest that students often superficially mapped the principles employed in the solved problem to the quiz problem without necessarily understanding the governing conditions underlying each principle and examining the applicability of the principle in the new situation in an in-depth manner. Findings suggest that more scaffolding is needed to help students in transferring from a two-step problem to a three-step problem and applying the physics principles appropriately. We outline a few

Using an isomorphic problem pair to learn introductory physics: Transferring from a two-step problem to a three-step problem

Science.gov (United States)

Lin, Shih-Yin; Singh, Chandralekha

2013-12-01

In this study, we examine introductory physics students’ ability to perform analogical reasoning between two isomorphic problems which employ the same underlying physics principles but have different surface features. 382 students from a calculus-based and an algebra-based introductory physics course were administered a quiz in the recitation in which they had to learn from a solved problem provided and take advantage of what they learned from it to solve another isomorphic problem (which we call the quiz problem). The solved problem provided has two subproblems while the quiz problem has three subproblems, which is known from previous research to be challenging for introductory students. In addition to the solved problem, students also received extra scaffolding supports that were intended to help them discern and exploit the underlying similarities of the isomorphic solved and quiz problems. The data analysis suggests that students had great difficulty in transferring what they learned from a two-step problem to a three-step problem. Although most students were able to learn from the solved problem to some extent with the scaffolding provided and invoke the relevant principles in the quiz problem, they were not necessarily able to apply the principles correctly. We also conducted think-aloud interviews with six introductory students in order to understand in depth the difficulties they had and explore strategies to provide better scaffolding. The interviews suggest that students often superficially mapped the principles employed in the solved problem to the quiz problem without necessarily understanding the governing conditions underlying each principle and examining the applicability of the principle in the new situation in an in-depth manner. Findings suggest that more scaffolding is needed to help students in transferring from a two-step problem to a three-step problem and applying the physics principles appropriately. We outline a few possible strategies

Anza palaeoichnological site. Late Cretaceous. Morocco. Part II. Problems of large dinosaur trackways and the first African Macropodosaurus trackway

Science.gov (United States)

Masrour, Moussa; Lkebir, Noura; Pérez-Lorente, Félix

2017-10-01

The Anza site shows large ichnological surfaces indicating the coexistence in the same area of different vertebrate footprints (dinosaur and pterosaur) and of different types (tridactyl and tetradactyl, semiplantigrade and rounded without digit marks) and the footprint variability of long trackways. This area may become a world reference in ichnology because it contains the second undebatable African site with Cretaceous pterosaur footprints - described in part I - and the first African site with Macropodosaurus footprints. In this work, problems related to long trackways are also analyzed, such as their sinuosity, the order-disorder of the variability (long-short) of the pace length and the difficulty of morphological classification of the theropod footprints due to their morphological variability.

Studying the Variable Refrigerant Volume (VRV) System and Determining the Root Cause of its Problem in Building 37, Malaysian Nuclear Agency

International Nuclear Information System (INIS)

Suhafizudin Zainal Anuar; Mohamad Suhaimi Yahaya; Jusnan Hasim; Suhilah Mohd Ali; Mohd Khafidz Shamsuddin

2015-01-01

Variable Refrigerant Volume (VRV) system is one of the Heating, Ventilation and Air Conditioning (HVAC) type in the building. VRV system is a multi-split type air conditioner that uses variable refrigerant flow control to provide customers with the ability to maintain individual zone control in each room and floor of a building. VRV used in Building 37 is made by Mitsubishi Heavy Industries that was completely installed in 2011 with two pipes system format. The objectives of this study are to understand the Variable Refrigerant Volume (VRV) system and also to study the root cause of its problem in Building 37, Agensi Nuklear Malaysia. The result of the study study suggests poor workmanship during installation process and insufficient electrical grounding are suspected as the causes of on-going and repeating problems occurred. Hence, Bahagian Kejuruteraan (BKJ) has worked out with the service contractor to identify the main problem and leaking area before proceeding with repair and commissioning activities. (author)

The psychosocial burden of childhood overweight and obesity: evidence for persisting difficulties in boys and girls.

Science.gov (United States)

Gibson, Lisa Y; Allen, Karina L; Davis, Elizabeth; Blair, Eve; Zubrick, Stephen R; Byrne, Susan M

2017-07-01

There is evidence that overweight and obese children tend to remain overweight or obese into adolescence and adulthood. However, little is known about the long-term psychosocial outcomes of childhood overweight and obesity. This study aimed to investigate the course of psychosocial difficulties over a 2-year period for children who were overweight or obese at baseline, and a sample of children who were a healthy weight at baseline. Participants were 212 children aged 8 to 13 years at baseline, who were participating in the Childhood Growth and Development (GAD) Study. Questionnaire and interview measures were used to assess children's self-esteem, depressive symptoms, body image, eating disorder symptoms, experiences with bullying, family satisfaction and quality of life. Linear mixed models were used to consider longitudinal changes in psychosocial variables. Overweight and obese children reported greater psychosocial distress than healthy weight children, and these differences were more pronounced for girls than boys. Weight and psychosocial impairment showed stability from baseline to 2-year follow-up. The results of this study suggest that psychosocial difficulties show considerable stability in childhood, for overweight/obese and healthy weight children. What is Known: • Childhood obesity tracks into adolescence and adulthood. • Physical health problems associated with childhood obesity also persist to adulthood. What is New: • Overweight and obese children are at risk of ongoing psychosocial distress from childhood into early adolescence.

Effectiveness of a 'Workshop on Decluttering and Organising' programme for teens and middle-aged adults with difficulty decluttering: a study protocol of an open-label, randomised, parallel-group, superiority trial in Japan.

Science.gov (United States)

Aso, Yasuko; Yamaoka, Kazue; Nemoto, Asuka; Naganuma, Yuki; Saito, Masashige

2017-06-10

Hoarding disorder can cause problems with work performance, personal hygiene, health and well-being. The disorder is a growing social problem in Japan. Having difficulty discarding rubbish, decluttering and organising can signal a future hoarding disorder, and early intervention is important. We developed an educational workshop on decluttering and organising for teens and adults with difficulty organising. The objective of this study is to evaluate the effectiveness of a workshop for reducing clutter and improving quality of life among younger people with difficulty decluttering and organising. An open-label, parallel-group, randomised controlled trial will be conducted among volunteers aged 12-55 years with mild difficulty decluttering and organising. Those in the intervention group will attend the workshop and receive a visit from a professional cleaning company to declutter their living space. The control group will have only the latter. The primary outcome will be the score on the Japanese version of the Saving Inventory-Revised. Secondary outcomes will be scores on the Clutter Image Rating Scale, the Japanese version of the Rosenberg Self-Esteem Scale and the Roles of Private Space Scale. The results will be examined for differences between the two groups in changes from baseline to 7 months. We will examine crude effects and adjust for gender and age using a general linear model for continuous variables and a logistic regression model for dichotomous variables. Sample size was calculated assuming a significance level of 5% (two tailed), a power of 80% and an effect size of 0.75. In total, 60 subjects (30 in each group) will be required. The study protocol has been approved by the Medical Ethical Committee of Teikyo University (No. 15-065). The findings will be disseminated widely through peer-reviewed publication and conference presentations. UMIN000020568. Issue date: 16 January 2016. © Article author(s) (or their employer(s) unless otherwise stated in the

Residents in difficulty

DEFF Research Database (Denmark)

Christensen, Mette Krogh; O'Neill, Lotte; Hansen, Dorthe Høgh

2016-01-01

Background The majority of studies on prevalence and characteristics of residents in difficulty have been conducted in English-speaking countries and the existing literature may not reflect the prevalence and characteristics of residents in difficulty in other parts of the world such as the Scand...... in a healthcare system. From our perspective, further sociological and pedagogical investigations in educational cultures across settings and specialties could inform our understanding of and knowledge about pitfalls in residents’ and doctors’ socialization into the healthcare system....

Secretary Problems: Weights and Discounts

NARCIS (Netherlands)

M. Babaioff; M. Dinitz; A. Gupta; N.S. Immorlica (Nicole Simone); K. Talwar

2009-01-01

textabstractThe classical secretary problem studies the problem of selecting online an element (a “secretary”) with maximum value in a randomly ordered sequence. The difficulty lies in the fact that an element must be either selected or discarded upon its arrival, and this decision is irrevocable.

Difference method for solving a nonlocal boundary value problem for a degenerating third-order pseudo-parabolic equation with variable coefficients

Science.gov (United States)

Beshtokov, M. Kh.

2016-10-01

A nonlocal boundary value problem for a degenerating third-order pseudo-parabolic equation with variable coefficients is considered. For solving this problem, a priori estimates in the differential and difference forms are obtained. The a priori estimates imply the uniqueness and stability of the solution on a layer with respect to the initial data and the right-hand side and the convergence of the solution of the difference problem to the solution of the differential problem.

A hybrid algorithm for flexible job-shop scheduling problem with setup times

Directory of Open Access Journals (Sweden)

Ameni Azzouz

2017-01-01

Full Text Available Job-shop scheduling problem is one of the most important fields in manufacturing optimization where a set of n jobs must be processed on a set of m specified machines. Each job consists of a specific set of operations, which have to be processed according to a given order. The Flexible Job Shop problem (FJSP is a generalization of the above-mentioned problem, where each operation can be processed by a set of resources and has a processing time depending on the resource used. The FJSP problems cover two difficulties, namely, machine assignment problem and operation sequencing problem. This paper addresses the flexible job-shop scheduling problem with sequence-dependent setup times to minimize two kinds of objectives function: makespan and bi-criteria objective function. For that, we propose a hybrid algorithm based on genetic algorithm (GA and variable neighbourhood search (VNS to solve this problem. To evaluate the performance of our algorithm, we compare our results with other methods existing in literature. All the results show the superiority of our algorithm against the available ones in terms of solution quality.

The effect of question format and task difficulty on reasoning strategies and diagnostic performance in Internal Medicine residents.

Science.gov (United States)

Heemskerk, Laura; Norman, Geoff; Chou, Sophia; Mintz, Marcy; Mandin, Henry; McLaughlin, Kevin

2008-11-01

Previous studies have suggested an association between reasoning strategies and diagnostic success, but the influence on this relationship of variables such as question format and task difficulty, has not been studied. Our objective was to study the association between question format, task difficulty, reasoning strategies and diagnostic success. Study participants were 13 Internal Medicine residents at the University of Calgary. Each was given eight problem-solving questions in four clinical presentations and were randomized to groups that differed only in the question format, such that a question presented as short answer (SA) to the first group was presented as extended matching (EM) to the second group. There were equal numbers of SA/EM questions and straightforward/difficult tasks. Participants performed think-aloud during diagnostic reasoning. Data were analyzed using multiple logistic regression. Question format was associated with reasoning strategies; hypothetico-deductive reasoning being used more frequently on EM questions and scheme-inductive reasoning on SA questions. For SA question, non-analytic reasoning alone was used more frequently to answer straightforward cases than difficult cases, whereas for EM questions no such association was observed. EM format and straightforward task increased the odds of diagnostic success, whereas hypothetico-deductive reasoning was associated with reduced odds of success. Question format and task difficulty both influence diagnostic reasoning strategies and studies that examine the effect of reasoning strategies on diagnostic success should control for these effects. Further studies are needed to investigate the effect of reasoning strategies on performance of different groups of learners.

The role of post-migration living difficulties on somatization among first-generation immigrants visited in a primary care service

Directory of Open Access Journals (Sweden)

Massimiliano Aragona

2011-01-01

Full Text Available The role of post-migration living difficulties (PMLD on somatization was studied in 101 first generation immigrants visited in primary care. Premigratory traumas and post-traumatic stress disorder (PTSD were also assessed. About one third of patients somatized. Sociodemographic variables were similar in somatizers and non-somatizers. Premigratory traumas, PTSD and the likelihood to report at least one serious or very serious PMLD were higher in somatizers. Four kinds of PMLD were more frequent in somatizers: worries about unavailability of health assistance, working problems, discrimination and poor social help. Traumas and PTSD influenced the effect of PMLD on somatization. Findings suggest that in specific samples of primary care immigrants severe premigratory traumas increase the sensitivity to PMLD and in turn distress due to PMLD amplifies the tendency to somatize.

Walking modality, but not task difficulty, influences the control of dual-task walking.

Science.gov (United States)

Wrightson, J G; Smeeton, N J

2017-10-01

During dual-task gait, changes in the stride-to-stride variability of stride time (STV) are suggested to represent the allocation of cognitive control to walking [1]. However, contrasting effects have been reported for overground and treadmill walking, which may be due to differences in the relative difficulty of the dual task. Here we compared the effect of overground and treadmill dual-task walking on STV in 18 healthy adults. Participants walked overground and on a treadmill for 120s during single-task (walking only) and dual-task (walking whilst performing serial subtractions in sevens) conditions. Dual-task effects on STV, cognitive task (serial subtraction) performance and perceived task difficulty were compared between walking modalities. STV was increased during overground dual-task walking, but was unchanged during treadmill dual-task walking. There were no differences in cognitive task performance or perceived task difficulty. These results show that gait is controlled differently during overground and treadmill dual-task walking. However, these differences are not solely due to differences in task difficulty, and may instead represent modality dependent control strategies. Copyright © 2017 Elsevier B.V. All rights reserved.

Adolescent Bullying and Sleep Difficulties

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Simon C. Hunter

2014-11-01

Full Text Available This study evaluated whether adolescents who report having been bullied, being bullies, or report both being a bully and being bullied experience more sleep difficulties than children uninvolved in bullying. The study drew upon cognitive theories of insomnia, investigating whether the extent to which young people report worrying about bullying can moderate associations between victimization and sleep difficulties. Participants were 5420 adolescents who completed a self-report questionnaire. Pure Victims (OR = 1.72, 95% CI [1.07, 2.75], Pure Bullies (OR = 1.80, 95% CI [1.16, 2.81], and Bully-Victims (OR = 2.90, 95% CI [1.17, 4.92] were all more likely to experience sleep difficulties when compared to uninvolved young people. The extent to which young people reported worrying about being bullied did not moderate the links between victimization and sleep difficulties. In this way, bullying is clearly related to sleep difficulties among adolescents but the conceptual reach of the cognitive model of insomnia in this domain is questioned.

Variable importance and prediction methods for longitudinal problems with missing variables.

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Iván Díaz

Full Text Available We present prediction and variable importance (VIM methods for longitudinal data sets containing continuous and binary exposures subject to missingness. We demonstrate the use of these methods for prognosis of medical outcomes of severe trauma patients, a field in which current medical practice involves rules of thumb and scoring methods that only use a few variables and ignore the dynamic and high-dimensional nature of trauma recovery. Well-principled prediction and VIM methods can provide a tool to make care decisions informed by the high-dimensional patient's physiological and clinical history. Our VIM parameters are analogous to slope coefficients in adjusted regressions, but are not dependent on a specific statistical model, nor require a certain functional form of the prediction regression to be estimated. In addition, they can be causally interpreted under causal and statistical assumptions as the expected outcome under time-specific clinical interventions, related to changes in the mean of the outcome if each individual experiences a specified change in the variable (keeping other variables in the model fixed. Better yet, the targeted MLE used is doubly robust and locally efficient. Because the proposed VIM does not constrain the prediction model fit, we use a very flexible ensemble learner (the SuperLearner, which returns a linear combination of a list of user-given algorithms. Not only is such a prediction algorithm intuitive appealing, it has theoretical justification as being asymptotically equivalent to the oracle selector. The results of the analysis show effects whose size and significance would have been not been found using a parametric approach (such as stepwise regression or LASSO. In addition, the procedure is even more compelling as the predictor on which it is based showed significant improvements in cross-validated fit, for instance area under the curve (AUC for a receiver-operator curve (ROC. Thus, given that 1 our VIM

Parents' and Teachers' Opinions of Preschool Children's Social Problem-Solving and Behavioural Problems

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Kasik, László; Gál, Zita

2016-01-01

The aim of our study was to shed light on (1) what Hungarian mothers, fathers and teachers of 4-6-year-olds think of these children's social problem-solving (SPS) and their difficulties in terms of problem-solving, adaptability and prosocial behaviour; (2) studying any correlation between the examined aspects and (3) the connection between one's…

Older age, higher perceived disability and depressive symptoms predict the amount and severity of work-related difficulties in persons with multiple sclerosis.

Science.gov (United States)

Raggi, Alberto; Giovannetti, Ambra Mara; Schiavolin, Silvia; Brambilla, Laura; Brenna, Greta; Confalonieri, Paolo Agostino; Cortese, Francesca; Frangiamore, Rita; Leonardi, Matilde; Mantegazza, Renato Emilio; Moscatelli, Marco; Ponzio, Michela; Torri Clerici, Valentina; Zaratin, Paola; De Torres, Laura

2018-04-16

This cross-sectional study aims to identify the predictors of work-related difficulties in a sample of employed persons with multiple sclerosis as addressed with the Multiple Sclerosis Questionnaire for Job Difficulties. Hierarchical linear regression analysis was conducted to identify predictors of work difficulties: predictors included demographic variables (age, formal education), disease duration and severity, perceived disability and psychological variables (cognitive dysfunction, depression and anxiety). The targets were the questionnaire's overall score and its six subscales. A total of 177 participants (108 females, aged 21-63) were recruited. Age, perceived disability and depression were direct and significant predictors of the questionnaire total score, and the final model explained 43.7% of its variation. The models built on the questionnaire's subscales show that perceived disability and depression were direct and significant predictors of most of its subscales. Our results show that, among patients with multiple sclerosis, those who were older, with higher perceived disability and higher depression symptoms have more and more severe work-related difficulties. The Multiple Sclerosis Questionnaire for Job Difficulties can be fruitfully exploited to plan tailored actions to limit the likelihood of near-future job loss in persons of working age with multiple sclerosis. Implications for rehabilitation Difficulties with work are common among people with multiple sclerosis and are usually addressed in terms of unemployment or job loss. The Multiple Sclerosis Questionnaire for Job Difficulties is a disease-specific questionnaire developed to address the amount and severity of work-related difficulties. We found that work-related difficulties were associated to older age, higher perceived disability and depressive symptoms. Mental health issues and perceived disability should be consistently included in future research targeting work-related difficulties.

The difficulties of teacher in teaching geometry for mental retardation students

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Shomad, Z. A.; Kusmayadi, T. A.; Riyadi

2018-03-01

The purpose of this research is to find out the problems faced by teachers in teaching materials on mental retardation students. It focused on the difficulties faced by the teacher in teaching geometry. A qualitative method with field study approach used in this study. The subjects in this research are the teacher and mild mental retardation students. There are six teachers and six students involve as the subject which is chosen by purposive sampling. The data of this research is the observation and interview against teachers and mental retardation students. The data was analyzed qualitatively with Miles and Huberman steps. The results of this research show that mental retardation students have less attention to the materials, less special books or learning media props, difficult in the set the students, and the difficulty in choosing the material that suits the student needs and the condition of mental retardation students. There's not much pay attention to the children with special need, particularly mental retardation student. Thus, this study can help analyze the difficulties teachers so that learning math for mental retardation students more optimal.

NECCESITY AND DIFFICULTY OF R D PERFORMANCEMEASUREMENT

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MariaFekete-Farkas

2012-07-01

Full Text Available We are living in a globalized world with increasing population which is facingsevere global economic and financial crises as well as serious environmentalproblems. The possibilities to overcome these difficulties can be interpreted asthe need for sustainable development calling for innovation, increased R Dspending with increased R D effectiveness and efficiency. Besides greaterattentionforthe need of deeper understanding of the innovation process and therole of R D in it, this paper has discussed the many analytical problems thatconfront a researcher in this area, and additionally calls for research oncollaboration between universities and industry. Among other conclusions thispaper also provides a new way of thinking for policy makers and performancemonitoring committees.

Common Group Problems: A Field Study.

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Weinberg, Sanford B.; And Others

1981-01-01

A field study of a naturally functioning group (N=125) was conducted to identify common group problems. Trained observers attended group meetings and described the problems encountered. Difficulties of cohesion, leadership, sub-group formation, and personality conflict were identified. (RC)

Special needs children with speech and hearing difficulties: prevalence and unmet needs.

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Kenney, Mary Kay; Kogan, Michael D

2011-01-01

The purpose of this study was to establish prevalences and sociodemographic characteristics associated with parent-reported speech and hearing difficulties among children with special health care needs (CSHCN); determine unmet needs for therapy, hearing aids, and communication devices; and examine the association between unmet needs and resources such as health insurance, early intervention/special education, and a medical home. Data were analyzed for 300,910 children without special health care needs and 40,723 CSHCN from the 2005-2006 National Survey of Children with Special Health Care Needs. Prevalence, sociodemographic characteristics, and unmet needs for 7132 CSHCN with speech difficulties and 1982 CSHCN with hearing difficulties were assessed. Logistic regression was used to determine the associations between unmet needs for therapy or hearing/communication devices and resources for addressing needs for therapy, hearing, and communication aids. The parent-reported prevalence of speech difficulty among CSHCN in the general population was 2.9% and approximately 20% among all CSHCN, in contrast to the lower prevalence of hearing difficulty (0.7% and 5%, respectively). Relative unmet need was greatest for communication devices and least for hearing aids. The strongest association with reducing unmet needs was having a medical home, and the most significant aspect of medical home was having effective care coordination. Having a medical home is significantly associated with fewer unmet needs for therapy and hearing/communication devices among CSHCN with speech and hearing difficulties. Care coordination may constitute an important factor that allows the primary care provider to link with services that CSHCN with communication problems require. Published by Elsevier Inc.

Understanding alcoholics’ “difficulty in life”: An empirical comparison of alcoholics and nonalcoholics

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Keiko Ito

2017-01-01

Full Text Available The Japanese success rate for alcoholism treatment is approximately 30%, indicating high relapse rates. Although “difficulty in life” is thought to contribute to alcoholics’ relapse, the characteristics of the phenomenon are unknown. This study examined the factors contributing to alcoholics’ difficulty in life. Alcoholic self-help group members, who indicated the extent of their difficulty in life and described the factors that contributed to this difficulty, completed a self-administered questionnaire. Participants’ hypersensitivity/grandiosity traits were also examined. A control group of nonalcoholic men also completed the questionnaire. Simple tabulation, descriptive statistics, Mann-Whitney U tests, and multivariate analyses were used to compare data between groups. Ultimately, 574 and 512 valid responses were received from the alcoholic (response rate: 27.1% and nonalcoholic (response rate: 33.1% groups, respectively. The proportion of alcoholics (54% who indicated that they found life difficult was significantly higher relative to that of nonalcoholics (39.9%. Alcoholics’ mean hypersensitivity score was significantly higher (2.67 relative to that observed for nonalcoholics (2.44. Significant between-group differences were observed for the following factors: building and maintaining relationships, satisfaction with life, self-distrust, cognitive bias, loneliness, empathic understanding, and self-acceptance. Multivariate logistic regression identified cognitive bias and building and maintaining relationships as factors contributing to alcoholics’ difficulty in life. Alcoholics’ social contexts, including broken families, social instability, and cross addiction, also contributed to this difficulty. Personal characteristics, such as hypersensitive-type narcissistic tendencies, relationship problems, and cognitive bias, were also associated with alcoholics’ difficulty in life.

Secretary Problems: Weights and Discounts

OpenAIRE

Babaioff, M.; Dinitz, M.; Gupta, A.; Immorlica, Nicole Simone; Talwar, K.

2009-01-01

textabstractThe classical secretary problem studies the problem of selecting online an element (a “secretary”) with maximum value in a randomly ordered sequence. The difficulty lies in the fact that an element must be either selected or discarded upon its arrival, and this decision is irrevocable. Constant-competitive algorithms are known for the classical secretary problems and several variants. We study the following two extensions of the secretary problem: In the discounted secretary probl...

Effectiveness of a ‘Workshop on Decluttering and Organising’ programme for teens and middle-aged adults with difficulty decluttering: a study protocol of an open-label, randomised, parallel-group, superiority trial in Japan

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Aso, Yasuko; Yamaoka, Kazue; Nemoto, Asuka; Naganuma, Yuki; Saito, Masashige

2017-01-01

Introduction Hoarding disorder can cause problems with work performance, personal hygiene, health and well-being. The disorder is a growing social problem in Japan. Having difficulty discarding rubbish, decluttering and organising can signal a future hoarding disorder, and early intervention is important. We developed an educational workshop on decluttering and organising for teens and adults with difficulty organising. The objective of this study is to evaluate the effectiveness of a workshop for reducing clutter and improving quality of life among younger people with difficulty decluttering and organising. Methods and analysis An open-label, parallel-group, randomised controlled trial will be conducted among volunteers aged 12–55 years with mild difficulty decluttering and organising. Those in the intervention group will attend the workshop and receive a visit from a professional cleaning company to declutter their living space. The control group will have only the latter. The primary outcome will be the score on the Japanese version of the Saving Inventory-Revised. Secondary outcomes will be scores on the Clutter Image Rating Scale, the Japanese version of the Rosenberg Self-Esteem Scale and the Roles of Private Space Scale. The results will be examined for differences between the two groups in changes from baseline to 7 months. We will examine crude effects and adjust for gender and age using a general linear model for continuous variables and a logistic regression model for dichotomous variables. Sample size was calculated assuming a significance level of 5% (two tailed), a power of 80% and an effect size of 0.75. In total, 60 subjects (30 in each group) will be required. Ethics and dissemination The study protocol has been approved by the Medical Ethical Committee of Teikyo University (No. 15-065). The findings will be disseminated widely through peer-reviewed publication and conference presentations. Trial registration number UMIN000020568. Issue date: 16

Perceived Difficulties in e-Learning During the First Term at University

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Galina Kavaliauskienė

2013-08-01

Full Text Available Purpose—the focus of this article is to explore difficulties that are encountered by students during the first term at university. It is well known that students can have various problems in learning English and make mistakes in grammar, vocabulary, and pronunciation. The native language of a learner affects learning and using English. Speaking and e-listening are the skills that are more common on an everyday basis than reading and writing. Moreover, these skills are more difficult to master. English vocabulary presents another problem for language learners. Albeit, at the university level students study English for Specific Purposes (ESP, in other words, the foreign language for their future profession, and they might face particular difficulties in their studies of ESP. Design/methodology/approach—the research paper adopts the qualitative research approach. The questionnaire on learner perceptions of difficulties in e-learning was administered to students of three different specializations. Students’ self-assessments of achievements or failures were analysed. Findings. The results indicated that perceptions of difficulties to adapting to university studies depended on their chosen specialization. The findings show that undergraduates of all three investigated specializations encounter the same difficulties, but to a different degree. In other words, there are no significantly specific difficulties due to the complexity of the professional vocabulary that students must learn. The ratings of Psychology, Social Work and Public Policy and Management students reveal higher mean values and wider range of Standard Deviations than reported by other researchers (Berman, Cheng, 2001. The results obtained imply that Lithuanian learners are more positive than their foreign counterparts. Computations of Pearson’s correlations coefficients demonstrate that there are some good correlational relationships within each specialization. Research

Syntactic intergrowth problems with BCSCO and fabrication difficulties therefrom

International Nuclear Information System (INIS)

Morgan, P.E.D.; Ratto, J.J.; Housley, R.M.; Porter, J.R.

1988-01-01

EDXS performed on isolated particles of the Bi-Ca-Sr-Cu-O high-temperature ceramic superconductor has verified the presence of significant elemental exchange between the Ca and Sr, and, to a lesser extent, between Cu and Bi. Two primary preparations, identified as primarily 24.4 A and 30.6 A, respectively, are identified. The Cu:Bi ratio in the 30.6 A material is approximately 1:1 for most particles, although only a few particles of the nominally 24.4 A material have the expected 1:2 ratio. No unequivocal assignment of atomic composition to the predominantly 24.4 A or 30.6 A appears possible, if major syntactic problems are present. 22 references

Measuring Difficulty in English-Chinese Translation: Towards a General Model of Translation Difficulty

Science.gov (United States)

Sun, Sanjun

2012-01-01

Accurate assessment of a text's level of translation difficulty is critical for translator training and accreditation, translation research, and the language industry as well. Traditionally, people rely on their general impression to gauge a text's translation difficulty level. If the evaluation process is to be more effective and the…

Energy taxation difficulties

International Nuclear Information System (INIS)

Landsberg, H.H.

1993-01-01

This paper assesses what may be the underlying reasons for the Clinton administration's recent failure to pass the Btu Tax on energy sources and the current difficulties that this Administration is experiencing in acquiring nation wide consensus on a gasoline tax proposal. Two difficulties stand out - regional differences in climate and thus winter heating requirements, and the differences from state to state in transportation system preferences. The paper cites the positive aspects of energy taxation by noting the petroleum industry's efforts to develop a new less polluting reformulated gasoline

Strategies of solving arithmetic word problems in students with learning difficulties in mathematics

OpenAIRE

Kalan, Marko

2015-01-01

Problem solving as an important skill is, beside arithmetic, measure and algebra, included in standards of school mathematics (National Council of Teachers of Mathematics) (NCTM, 2000) and needed as a necessary skill for successfulness in science, technology, engineering and mathematics (STEM) (National Mathematics Advisory Panel, 2008). Since solving of human problems is connected to the real life, the arithmetic word problems (in short AWP) are an important kind of mathematics tasks in scho...

Difficulties faced by family physicians in primary health care centers in Jeddah, Saudi Arabia.

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Mumenah, Sahar H; Al-Raddadi, Rajaa M

2015-01-01

The aim was to determine the difficulties faced by family physicians, and compare how satisfied those working with the Ministry of Health (MOH) are with their counterparts who work at some selected non-MOH hospitals. An analytical, cross-sectional study was conducted at King Abdulaziz University Hospital, King Faisal Specialist Hospital and Research Center (KFSH and RC), and 40 MOH primary health care centers across Jeddah. A structured multi-item questionnaire was used to collect demographic data and information on the difficulties family physicians face. The physicians' level of satisfaction and how it was affected by the difficulties was assessed. Women constituted 71.9% of the sample. Problems with transportation formed one of the main difficulties encountered by physicians. Compared to non-MOH physician, a significantly higher proportion of MOH physicians reported unavailability of radiology technicians (P = 0.011) and radiologists (P building maintenance (P < 0.001). Family physicians with the MOH were less satisfied with their jobs compared with non-MOH physicians (P = 0.032). MOH family physicians encountered difficulties relating to staff, services, and infrastructure, which consequently affected their level of satisfaction.

Intervention program efficacy for spelling difficulties.

Science.gov (United States)

Sampaio, Maria Nobre; Capellini, Simone Aparecida

2014-01-01

To develop an intervention procedure for spelling difficulties and to verify the effectiveness of the intervention program in students with lower spelling performance. We developed an intervention program for spelling difficulties, according to the semiology of the errors. The program consisted of three modules totaling 16 sessions. The study included 40 students of the third to fifth grade of public elementary education of the city of Marilia (SP), of both genders, in aged of eight to 12 years old, being distributed in the following groups: GI (20 students with lower spelling performance) and GII (20 students with higher spelling performance). In situation of pre and post-testing, all groups were submitted to the Pro-Orthography. The results statistically analyzed showed that, in general, all groups had average of right that has higher in post-testing, reducing the types of errors second semiologycal classification, mainly related to natural spelling errors. However, the results also showed that the groups submitted to the intervention program showed better performance on spelling tests in relation to not submitted. The intervention program developed was effective once the groups submitted showed better performance on spelling tests in relation to not submitted. Therefore, the intervention program can help professionals in the Health and Education to minimize the problems related to spelling, giving students an intervention that is effective for the development of the spelling knowledge.

The Caterer's Problem.

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Krause, Eugene F.

1983-01-01

An approach to teaching problem solving to preservice and in-service middle school teachers is described. They examined an unsolved question as a class research project. The process of developing the solution is detailed, and difficulties contained within the process are noted. (MP)

Player Modeling Using HOSVD towards Dynamic Difficulty Adjustment in Videogames

OpenAIRE

Anagnostou , Kostas; Maragoudakis , Manolis

2012-01-01

Part 3: Second International Workshop on Computational Intelligence in Software Engineering (CISE 2012); International audience; In this work, we propose and evaluate a Higher Order Singular Value Decomposition (HOSVD) of a tensor as a means to classify player behavior and adjust game difficulty dynamically. Applying this method to player data collected during a plethora of game sessions resulted in a reduction of the dimensionality of the classification problem and a robust classification of...

Challenging problems in geometry

CERN Document Server

Posamentier, Alfred S

1996-01-01

Collection of nearly 200 unusual problems dealing with congruence and parallelism, the Pythagorean theorem, circles, area relationships, Ptolemy and the cyclic quadrilateral, collinearity and concurrency and more. Arranged in order of difficulty. Detailed solutions.

An investigation of difficulties experienced by students developing unified modelling language (UML) class and sequence diagrams

Science.gov (United States)

Sien, Ven Yu

2011-12-01

Object-oriented analysis and design (OOAD) is not an easy subject to learn. There are many challenges confronting students when studying OOAD. Students have particular difficulty abstracting real-world problems within the context of OOAD. They are unable to effectively build object-oriented (OO) models from the problem domain because they essentially do not know "what" to model. This article investigates the difficulties and misconceptions undergraduate students have with analysing systems using unified modelling language analysis class and sequence diagrams. These models were chosen because they represent important static and dynamic aspects of the software system under development. The results of this study will help students produce effective OO models, and facilitate software engineering lecturers design learning materials and approaches for introductory OOAD courses.

Greater repertoire and temporal variability of cross-frequency coupling (CFC modes in resting-state neuromagnetic recordings among children with reading difficulties

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Stavros I Dimitriadis

2016-04-01

Full Text Available AbstractCross-frequency, phase-to-amplitude coupling (PAC between neuronal oscillations at rest may serve as the substrate that supports information exchange between functionally specialized neuronal populations both within and between cortical regions. The study utilizes novel algorithms to identify prominent instantaneous modes of cross-frequency coupling and their temporal stability in resting state magnetoencephalography (MEG data from 23 students experiencing severe reading difficulties (RD and 27 age-matched non-impaired readers (NI.Phase coherence estimates were computed in order to identify the prominent mode of PAC interaction for each sensor, sensor pair, and pair of frequency bands (from δ to γ at successive temporal segments of the continuous MEG record. The degree of variability in the characteristic frequency-pair PACf1-f2 modes over time was also estimated. Results revealed a wider repertoire of prominent PAC interactions in RD as compared to NI students, suggesting an altered functional substrate for information exchange between neuronal assemblies in the former group. Moreover, RD students showed significant variability in PAC modes over time. This temporal instability of PAC values was particularly prominent: (a within and between right hemisphere temporal and occipitotemporal sensors and, (b between left hemisphere frontal, temporal, and occipitotemporal sensors and corresponding right hemisphere sites. Altered modes of neuronal population coupling may help account for extant data revealing reduced, task-related neurophysiological and hemodynamic activation in left hemisphere regions involved in the reading network in RD. Moreover, the spatial distribution of pronounced instability of cross-frequency coupling modes in this group may provide an explanation for previous reports suggesting the presence of inefficient compensatory mechanisms to support reading.

Predicting maternal parenting stress in middle childhood: the roles of child intellectual status, behaviour problems and social skills.

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Neece, C; Baker, B

2008-12-01

Parents of children with intellectual disabilities (ID) typically report elevated levels of parenting stress, and child behaviour problems are a strong predictor of heightened parenting stress. Interestingly, few studies have examined child characteristics beyond behaviour problems that may also contribute to parenting stress. The present longitudinal study examined the contribution of child social skills to maternal parenting stress across middle childhood, as well as the direction of the relationship between child social skills and parenting stress. Families of children with ID (n = 74) or typical development (TD) (n = 115) participated over a 2-year period. Maternal parenting stress, child behaviour problems and child social skills were assessed at child ages six and eight. Child social skills accounted for unique variance in maternal parenting stress above and beyond child intellectual status and child behaviour problems. As the children matured, there was a significant interaction between child social skills and behaviour problems in predicting parenting stress. With respect to the direction of these effects, a cross-lagged panel analysis indicated that early parenting stress contributed to later social skills difficulties for children, but the path from children's early social skills to later parenting stress was not supported, once child behaviour problems and intellectual status were accounted for. When examining parenting stress, child social skills are an important variable to consider, especially in the context of child behaviour problems. Early parenting stress predicted child social skills difficulties over time, highlighting parenting stress as a key target for intervention.

Measurement of functional task difficulty during motor learning: What level of difficulty corresponds to the optimal challenge point?

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Akizuki, Kazunori; Ohashi, Yukari

2015-10-01

The relationship between task difficulty and learning benefit was examined, as was the measurability of task difficulty. Participants were required to learn a postural control task on an unstable surface at one of four different task difficulty levels. Results from the retention test showed an inverted-U relationship between task difficulty during acquisition and motor learning. The second-highest level of task difficulty was the most effective for motor learning, while learning was delayed at the most and least difficult levels. Additionally, the results indicate that salivary α-amylase and the performance dimension of the National Aeronautics and Space Administration-Task Load Index (NASA-TLX) are useful indices of task difficulty. Our findings suggested that instructors may be able to adjust task difficulty based on salivary α-amylase and the performance dimension of the NASA-TLX to enhance learning. Copyright © 2015 Elsevier B.V. All rights reserved.

Diagnostic Assessment of the Difficulty Using Direct Policy Search in Many-Objective Reservoir Control

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Zatarain-Salazar, J.; Reed, P. M.; Herman, J. D.; Giuliani, M.; Castelletti, A.

2014-12-01

MOEA, are statistically superior for the six-objective Susquehanna instance of this important class of problems. Additionally, shifting from deterministic history-based DPS to stochastic DPS significantly increases the difficulty of the problem.

Benford's law and continuous dependent random variables

Science.gov (United States)

Becker, Thealexa; Burt, David; Corcoran, Taylor C.; Greaves-Tunnell, Alec; Iafrate, Joseph R.; Jing, Joy; Miller, Steven J.; Porfilio, Jaclyn D.; Ronan, Ryan; Samranvedhya, Jirapat; Strauch, Frederick W.; Talbut, Blaine

2018-01-01

Many mathematical, man-made and natural systems exhibit a leading-digit bias, where a first digit (base 10) of 1 occurs not 11% of the time, as one would expect if all digits were equally likely, but rather 30%. This phenomenon is known as Benford's Law. Analyzing which datasets adhere to Benford's Law and how quickly Benford behavior sets in are the two most important problems in the field. Most previous work studied systems of independent random variables, and relied on the independence in their analyses. Inspired by natural processes such as particle decay, we study the dependent random variables that emerge from models of decomposition of conserved quantities. We prove that in many instances the distribution of lengths of the resulting pieces converges to Benford behavior as the number of divisions grow, and give several conjectures for other fragmentation processes. The main difficulty is that the resulting random variables are dependent. We handle this by using tools from Fourier analysis and irrationality exponents to obtain quantified convergence rates as well as introducing and developing techniques to measure and control the dependencies. The construction of these tools is one of the major motivations of this work, as our approach can be applied to many other dependent systems. As an example, we show that the n ! entries in the determinant expansions of n × n matrices with entries independently drawn from nice random variables converges to Benford's Law.

Hearing difficulties, ear-related diagnoses and sickness absence or disability pension--a systematic literature review.

Science.gov (United States)

Friberg, Emilie; Gustafsson, Klas; Alexanderson, Kristina

2012-09-12

Hearing difficulties is a large public health problem, prognosticated to be the ninth leading burden of disease in 2030, and may also involve large consequences for work capacity. However, research regarding sickness absence and disability pension in relation to hearing difficulties is scarce. The aim was to gain knowledge about hearing difficulties or other ear-related diagnoses and sickness absence and disability pension through conducting a systematic literature review of published studies. Studies presenting empirical data on hearing difficulties or ear-related diagnoses and sick leave or disability pension, published in scientific peer-reviewed journals, were included. Studies were sought for in three ways: in literature databases (Pub-Med, Embase, PsycInfo, SSCI, and Cochrane) through March 2011, through scrutinising lists of references, and through contacts. Identified publications were assessed for relevance and data was extracted from the studies deemed relevant. A total of 18 studies were assessed as relevant and included in this review, regardless of scientific quality. Fourteen studies presented empirical data on hearing difficulties/ear diagnoses and sick leave and six on these conditions and disability pension. Only two studies presented rate ratios or odds ratios regarding associations between hearing difficulties and sick leave, and only two on hearing difficulties and risk of disability pension. Both measures of hearing difficulties and of sick leave varied considerable between the studies. Remarkably few studies on hearing difficulties in relation to sickness absence or disability pension were identified. The results presented in them cannot provide evidence for direction or magnitude of potential associations.

Screening foster children for mental disorders: properties of the strengths and difficulties questionnaire.

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Stine Lehmann

Full Text Available High prevalence of mental disorders among foster children highlight the need to examine the mental health of children placed out of home. We examined the properties of the Strengths and Difficulties Questionnaire (SDQ in screening school-aged foster children for mental disorders.Foster parents and teachers of 279 foster children completed the SDQ and the diagnostic interview Developmental and Well-Being Assessment (DAWBA. Using the diagnoses derived from the DAWBA as the standard, we examined the performance of the SDQ scales as dimensional measures of mental health problems using receiver operating characteristic (ROC analyses. Recommended cut-off scores were derived from ROC coordinates. The SDQ predictive algorithms were also examined.ROC analyses supported the screening properties of the SDQ Total difficulties and Impact scores (AUC = 0.80-0.83. Logistic regression analyses showed that the prevalence of mental disorders increased linearly with higher SDQ Total difficulties scores (X2 = 121.47, df = 13, p<.001 and Impact scores (X2 = 69.93, df = 6, p<.001. Our results indicated that there is an additive value of combining the scores from the Total difficulties and Impact scales, where scores above cut-off on any of the two scales predicted disorders with high sensitivity (89.1%, but moderate specificity (62.1%. Scores above cut-off on both scales yielded somewhat lower sensitivity (73.4%, but higher specificity (81.1%. The SDQ multi-informant algorithm showed low discriminative ability for the main diagnostic categories, with an exception being the SDQ Conduct subscale, which accurately predicted the absence of behavioural disorders (LHR- = 0.00.The results support the use of the SDQ Total difficulties and Impact scales when screening foster children for mental health problems. Cut-off values for both scales are suggested. The SDQ multi-informant algorithms are not recommended for mental health screening of foster

Using the Efficient Frontier to Obtain the Best Solution for the Storage Location Assignment Problem

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Marcele Elisa Fontana

2014-01-01

Full Text Available The main variables that influence the efficiency of a warehouse are the use of space and the order picking distance. In the literature, there are proposals to add the costs with space and order picking in order to evaluate each alternative for storage location assignment. However, there were problems with the adoption of this methodology, including difficulties in determining the costs and tradeoffs between them. These difficulties can result in solutions that are suboptimal. Based on these facts, this paper proposes a class-based storage process and storage location assignment by a cube-per-order index (COI that analyzes the space required and the total order picking distance by Pareto-optimal calculations. The efficient frontier possibilities allow the reduction of the set of alternatives, and the DM can analyze only the alternatives on efficient frontier.

Effects of dual task difficulty in motor and cognitive performance: Differences between adults and adolescents.

Science.gov (United States)

Bustillo-Casero, Pilar; Villarrasa-Sapiña, Israel; García-Massó, Xavier

2017-10-01

In the present study our aim was to compare dual-task performance in thirteen adolescents and fifteen young adults while concurrently performing a cognitive and a motor task. The postural control variables were obtained under three different conditions: i) bipedal stance, ii) tandem stance and iii) unipedal stance. The cognitive task consisted of a backward digit span test in which the participants were asked to memorize a sequence of numbers and then repeat the number in reverse order at three different difficulty levels (i.e. with 3, 4 and 5 digits). The difficulty of the cognitive task was seen to have different effects on adolescents and young adults. Adolescents seem to prioritize postural control during high difficulty postural conditions while a cross-domain competition model appeared in easy postural conditions. Copyright © 2017 Elsevier B.V. All rights reserved.

Polynomial Variables and the Jacobian Problem

Indian Academy of Sciences (India)

algebra and algebraic geometry, and ... algebraically, to making the change of variables (X, Y) r--t. (X +p, Y ... aX + bY + p and eX + dY + q are linear polynomials in X, Y. ..... [5] T T Moh, On the Jacobian conjecture and the confipration of roots,.

Problems Identifying Independent and Dependent Variables

Science.gov (United States)

Leatham, Keith R.

2012-01-01

This paper discusses one step from the scientific method--that of identifying independent and dependent variables--from both scientific and mathematical perspectives. It begins by analyzing an episode from a middle school mathematics classroom that illustrates the need for students and teachers alike to develop a robust understanding of…

The structure of algebraic problem in high schools

OpenAIRE

Chio, José Angel; Álvarez, Aida; Estrada, Pablo

2010-01-01

The paper is aimed at discussing the importance of pupil’s knowledge of algebraic problem structure. The research started by diagnosing pupil’s actual command of algebraic problem structure. Finally suggestions to teachers of mathematics for facing difficulties in solving problems are given.

Psychosocial characteristics of adolescent problem gambling

OpenAIRE

Dixon, Ramsay Wright

2017-01-01

Problem gambling among adolescents has emerged as a significant area of research interest. Youth gambling problems are associated with a range of interpersonal, familial, economic, psychological and legal problems. However, because not all adolescents who gamble will develop gambling problems, the research literature has begun to emphasise potential factors that may increase or ameliorate the risk of developing such difficulties. Those characteristics associated with higher levels of severity...

Nature and origins of mathematics difficulties in very preterm children: a different etiology than developmental dyscalculia.

Science.gov (United States)

Simms, Victoria; Gilmore, Camilla; Cragg, Lucy; Clayton, Sarah; Marlow, Neil; Johnson, Samantha

2015-02-01

Children born very preterm (mathematics learning difficulties that are out of proportion to other academic and cognitive deficits. However, the etiology of mathematics difficulties in very preterm children is unknown. We sought to identify the nature and origins of preterm children's mathematics difficulties. One hundred and fifteen very preterm children aged 8-10 y were assessed in school with a control group of 77 term-born classmates. Achievement in mathematics, working memory, visuospatial processing, inhibition, and processing speed were assessed using standardized tests. Numerical representations and specific mathematics skills were assessed using experimental tests. Very preterm children had significantly poorer mathematics achievement, working memory, and visuospatial skills than term-born controls. Although preterm children had poorer performance in specific mathematics skills, there was no evidence of imprecise numerical representations. Difficulties in mathematics were associated with deficits in visuospatial processing and working memory. Mathematics difficulties in very preterm children are associated with deficits in working memory and visuospatial processing not numerical representations. Thus, very preterm children's mathematics difficulties are different in nature from those of children with developmental dyscalculia. Interventions targeting general cognitive problems, rather than numerical representations, may improve very preterm children's mathematics achievement.

Reflections on the institutional difficulties to perform actions on risk management

International Nuclear Information System (INIS)

Leoz M, Francisco Javier

2008-01-01

In Colombia, risk management is organised through a set of norms which define hierarchic levels where some state agencies, amongst other duties, assume the task to administer risk prevention. This set of rules creates difficulties amongst agencies responsible for risk reduction. One of these problems is related to jurisdiction limits, which render impossible investments destined to reduce risk in areas lying outside legally defined territories. Another problem is the structure of the National System for Prevention and Relief of Disasters, which obliges municipalities to assume the whole responsibility. Furthermore, rules and management related to technical data are considered as obstacles for efficient risk management

Player Modeling for Intelligent Difficulty Adjustment

Science.gov (United States)

Missura, Olana; Gärtner, Thomas

In this paper we aim at automatically adjusting the difficulty of computer games by clustering players into different types and supervised prediction of the type from short traces of gameplay. An important ingredient of video games is to challenge players by providing them with tasks of appropriate and increasing difficulty. How this difficulty should be chosen and increase over time strongly depends on the ability, experience, perception and learning curve of each individual player. It is a subjective parameter that is very difficult to set. Wrong choices can easily lead to players stopping to play the game as they get bored (if underburdened) or frustrated (if overburdened). An ideal game should be able to adjust its difficulty dynamically governed by the player’s performance. Modern video games utilise a game-testing process to investigate among other factors the perceived difficulty for a multitude of players. In this paper, we investigate how machine learning techniques can be used for automatic difficulty adjustment. Our experiments confirm the potential of machine learning in this application.

On the photo-gravitational restricted four-body problem with variable mass

Science.gov (United States)

Mittal, Amit; Agarwal, Rajiv; Suraj, Md Sanam; Arora, Monika

2018-05-01

This paper deals with the photo-gravitational restricted four-body problem (PR4BP) with variable mass. Following the procedure given by Gascheau (C. R. 16:393-394, 1843) and Routh (Proc. Lond. Math. Soc. 6:86-97, 1875), the conditions of linear stability of Lagrange triangle solution in the PR4BP are determined. The three radiating primaries having masses m1, m2 and m3 in an equilateral triangle with m2=m3 will be stable as long as they satisfy the linear stability condition of the Lagrangian triangle solution. We have derived the equations of motion of the mentioned problem and observed that there exist eight libration points for a fixed value of parameters γ (m at time t/m at initial time, 0Cambridge University Press, Cambridge, 1928), 0≤α≤2.2), the mass parameter μ=0.005 and radiation parameters qi, (0< qi≤1, i=1, 2, 3). All the libration points are non-collinear if q2≠ q3. It has been observed that the collinear and out-of-plane libration points also exist for q2=q3. In all the cases, each libration point is found to be unstable. Further, zero velocity curves (ZVCs) and Newton-Raphson basins of attraction are also discussed.

Does the central limit theorem always apply to phase noise? Some implications for radar problems

Science.gov (United States)

Gray, John E.; Addison, Stephen R.

2017-05-01

The phase noise problem or Rayleigh problem occurs in all aspects of radar. It is an effect that a radar engineer or physicist always has to take into account as part of a design or in attempt to characterize the physics of a problem such as reverberation. Normally, the mathematical difficulties of phase noise characterization are avoided by assuming the phase noise probability distribution function (PDF) is uniformly distributed, and the Central Limit Theorem (CLT) is invoked to argue that the superposition of relatively few random components obey the CLT and hence the superposition can be treated as a normal distribution. By formalizing the characterization of phase noise (see Gray and Alouani) for an individual random variable, the summation of identically distributed random variables is the product of multiple characteristic functions (CF). The product of the CFs for phase noise has a CF that can be analyzed to understand the limitations CLT when applied to phase noise. We mirror Kolmogorov's original proof as discussed in Papoulis to show the CLT can break down for receivers that gather limited amounts of data as well as the circumstances under which it can fail for certain phase noise distributions. We then discuss the consequences of this for matched filter design as well the implications for some physics problems.

Sleep variability and fatigue in adolescents: Associations with school-related features.

Science.gov (United States)

Matos, M G; Gaspar, T; Tomé, G; Paiva, T

2016-10-01

This study aims to evaluate the influences of sleep duration and sleep variability (SleepV), upon adolescents' school-related situations. The Health Behaviour in School-Aged Children (HBSC) survey is based on a self-completed questionnaire. The participants were 3164 pupils (53.7% girls), attending the 8th and 10th grades, 14.9 years old, and were inquired about subjective sleep duration during the week and weekends, SleepV, fatigue, difficulties in sleep initiation, school achievement, feelings towards schools, pressure with school work and skipping classes. Multiple regression models used, as dependent variables: (a) school achievement, (b) disliking school, (c) pressure with school work and (d) skipping classes, using as independent variables, each of the remaining school-related variables, fatigue, total sleep duration and difficulties in sleep initiation. The average sleep duration in the week and during weekdays was lower than recommended for these age groups, and almost half of students had high SleepV between weekdays and weekends. A logistic model revealed that the absence of SleepV was associated with lower perception of school work pressure, less frequent skipping classes, more infrequent fatigue and more infrequent difficulties in sleep initiation. Poor sleep quality, SleepV and insufficient sleep duration affected negatively school-related variables. © 2015 International Union of Psychological Science.

Preliminary studies on a variable energy positron annihilation lifetime spectroscopy system

International Nuclear Information System (INIS)

Kwan, P.Y.; Cheung, C.K.; Beling, C.D.; Fung, S.

2006-01-01

There are many advantages in being able to perform positron annihilation lifetime spectroscopy (PALS) using a variable energy positron beam, the most obvious being the easy identification of different defect types at different depths. The difficulty in conducting variable energy (VE) PALS studies lies in the fact that a 'start' signal is required to signal the entry of the positron into the target. Two methods have been used to overcome this problem, namely the bunching technique, which employs radio frequency (RF) cavities and choppers, and secondly the use of secondary electrons emitted from the target. The latter technique is in terms of experimental complexity much simpler, but has in the past suffered from poor time resolution (typically ∼500 ps). In this work, we present a series of computer simulations of a design based on the secondary electron emission from thin C-foils in transmission mode which shows that significant improvements in time resolution can be made with resolutions ∼200 ps being in principle possible

Is severity of motor coordination difficulties related to co-morbidity in children at risk for developmental coordination disorder?

Science.gov (United States)

Schoemaker, Marina M; Lingam, Raghu; Jongmans, Marian J; van Heuvelen, Marieke J G; Emond, Alan

2013-10-01

Aim of the study was to investigate whether 7-9 year old children with severe motor difficulties are more at risk of additional difficulties in activities in daily living, academic skills, attention and social skills than children with moderate motor difficulties. Children (N=6959) from a population based cohort, the Avon Longitudinal Study of Parents and Children (ALSPAC), were divided into three groups based on their scores on the ALSPAC Coordination Test at age 7: control children (scores above 15th centile; N=5719 [82.1%]); children with moderate (between 5th and 15th centile; N=951 [13.7%]); and children with severe motor difficulties (below 5th centile N=289 [4.2%]). Children with neurological disorders or an IQactivities of daily living (ADL); academic skills (reading, spelling and handwriting); attention; social skills (social cognition and nonverbal skills). Children with severe motor difficulties demonstrated a higher risk of difficulties in ADL, handwriting, attention, reading, and social cognition than children with moderate motor difficulties, who in turn had a higher risk of difficulties than control children in five out of seven domains. Screening and intervention of co-morbid problems is recommended for children with both moderate and severe motor difficulties. Copyright © 2013. Published by Elsevier Ltd.

Strategy Keys as Tools for Problem Solving

Science.gov (United States)

Herold-Blasius, Raja

2017-01-01

Problem solving is one of the main competences we seek to teach students at school for use in their future lives. However, when dealing with mathematical problems, teachers encounter a wide variety of difficulties. To foster students' problem-solving skills, the authors developed "strategy keys." Strategy keys can serve as material to…

Blink activity and task difficulty.

Science.gov (United States)

Tanaka, Y; Yamaoka, K

1993-08-01

This study investigated the relationship between task difficulty and blink activity, which includes blink rate, blink amplitude, and blink duration. Two kinds of tasks established two levels of difficulty. In Exp. 1, a mental arithmetic task was used to examine the relationship. Analysis showed that blink rate for a difficult task was significantly higher than that for an easier one. In Exp. 2, a letter-search task (hiragana Japanese alphabet) was used while the other conditions were the same as those in Exp. 1; however, the results of this experiment were not influenced by the difficulty of the task. As results indicate that blink rate is related to not only difficulty but also the nature of the task, the nature of the task is probably dependent on a mechanism in information processing. The results for blink amplitude and blink duration showed no systematic change during either experiment.

Does parent-child agreement vary based on presenting problems? Results from a UK clinical sample.

Science.gov (United States)

Cleridou, Kalia; Patalay, Praveetha; Martin, Peter

2017-01-01

Discrepancies are often found between child and parent reports of child psychopathology, nevertheless the role of the child's presenting difficulties in relation to these is underexplored. This study investigates whether parent-child agreement on the conduct and emotional scales of the Strengths and Difficulties Questionnaire (SDQ) varied as a result of certain child characteristics, including the child's presenting problems to clinical services, age and gender. The UK-based sample consisted of 16,754 clinical records of children aged 11-17, the majority of which were female (57%) and White (76%). The dataset was provided by the Child Outcomes Research Consortium , which collects outcome measures from child services across the UK. Clinicians reported the child's presenting difficulties, and parents and children completed the SDQ. Using correlation analysis, the main findings indicated that agreement varied as a result of the child's difficulties for reports of conduct problems, and this seemed to be related to the presence or absence of externalising difficulties in the child's presentation. This was not the case for reports of emotional difficulties. In addition, agreement was higher when reporting problems not consistent with the child's presentation; for instance, agreement on conduct problems was greater for children presenting with internalising problems. Lastly, the children's age and gender did not seem to have an impact on agreement. These findings demonstrate that certain child presenting difficulties, and in particular conduct problems, may be related to informant agreement and need to be considered in clinical practice and research. Trial Registration This study was observational and as such did not require trial registration.

RANKING THE SPECTATORS’ DIFFICULTIES IN PURCHASING ELECTRONIC TICKETS OF FOOTBALL PREMIER LEAGUE

Directory of Open Access Journals (Sweden)

Ahmad Narimani

2017-04-01

Full Text Available This study aimed to rank the spectators’ difficulties in buying electronic tickets of football premier league matches at Azadi stadium. The population consisted of all spectators of Esteghlal-Persepolis match in the fifteenth league at Azadi stadium (N= 100000. According to Morgan table and using simple random sampling method, 500 participants were selected as sample. A researcher-made questionnaire was used for collecting the data; its face validity was confirmed by 15 experts and performing a pilot study on 30 subjects, its Cronbach’s alpha was calculated to be 0.86. Using SPSS 22, the descriptive and inferential (including Friedman test statistics was applied for analyzing the data. The findings showed that there was a significant difference between rankings of difficulties in buying electronic tickets of Football premier league matches at Azadi Stadium. The difficulties were ranked as: problem in ticket systems, early selling out of electronic tickets, lack of confidence to electronic ticket sale, lack of skill to work with the internet, low speed of internet, and lack of access to the internet

Addressing Students' Difficulties with Faraday's Law: A Guided Problem Solving Approach

Science.gov (United States)

Zuza, Kristina; Almudí, José-Manuel; Leniz, Ane; Guisasola, Jenaro

2014-01-01

In traditional teaching, the fundamental concepts of electromagnetic induction are usually quickly analyzed, spending most of the time solving problems in a more or less rote manner. However, physics education research has shown that the fundamental concepts of the electromagnetic induction theory are barely understood by students. This article…

Early emotional and behavioral difficulties and adult educational attainment: an 18-year follow-up of the TEMPO study.

Science.gov (United States)

Zbar, Ariella; Surkan, Pamela J; Fombonne, Eric; Melchior, Maria

2016-10-01

Children who experience behavioral difficulties often have short and long-term school problems. However, the relationship between emotional difficulties and later academic achievement has not been thoroughly examined. Using data from the French TEMPO study (n = 666, follow-up 1991, 1999, 2009, mean age = 10.5, sd = 4.9 at baseline), we studied associations between internalizing and externalizing symptoms in: (a) childhood and (b) adolescence and educational attainment by young adulthood (educational attainment; however, in multivariate models only the association with childhood internalizing symptoms remained statistically significant (OR = 1.75, 95 % CI 1.00-3.02). Supporting children with internalizing problems early on could help improve their long-term educational attainment.

The structure of algebraic problem in high schools

Directory of Open Access Journals (Sweden)

Chio, José Angel

2010-01-01

Full Text Available The paper is aimed at discussing the importance of pupil’s knowledge of algebraic problem structure. The research started by diagnosing pupil’s actual command of algebraic problem structure. Finally suggestions to teachers of mathematics for facing difficulties in solving problems are given.

CONTRIBUTING FACTORS TOWARDS DIFFICULTIES IN GENERATING IDEAS AMONG TECHNICAL STUDENTS

OpenAIRE

Yee Mei Heong

2013-01-01

Idea is a thought or collection of thoughts that are important to decision making and problem solving.  The purpose of this research was to analysis the factors contributing to difficulty in generating ideas among technical students.  A total of 375 technical students from four technical universities in Malaysia were randomly selected as samples.  A set of questionnaires was developed and used as research instrument.  The findings indicated that a total of 319 (85.1%) technical students faced...

An analysis of the perceived difficulties arising during the process of integrating management systems

Directory of Open Access Journals (Sweden)

Jesus Abad

2016-09-01

Originality/value: Most research emphasises the benefits of integrated management systems. By analysing the difficulties that arise during the integration process, this study contributes to fill a gap in the literature on the problems associated with processes of organisational change, in our case the integration of management systems.

Growth and prevalence of feeding difficulties in children with Robin sequence : a retrospective cohort study

NARCIS (Netherlands)

Paes, Emma C.; de Vries, Iris A C; Penris, Wouter M.; Hanny, Karlijn H.; Lavrijsen, Selma W.; van Leerdam, Elselien K.; Rademaker, Maaike M.; Veldhoen, Esther S.; Eijkemans, Rene M J C; Kon, Moshe; Breugem, Corstiaan C.

Objectives: In addition to breathing problems, patients with Robin sequence (RS) often encounter feeding difficulties (FD). Data regarding the occurrence of FD and possible influencing factors are scarce. The study aim was to elucidate these factors to improve treatment strategies. Material and

Sensory-motor problems in Autism

Science.gov (United States)

Whyatt, Caroline; Craig, Cathy

2013-01-01

Despite being largely characterized as a social and cognitive disorder, strong evidence indicates the presence of significant sensory-motor problems in Autism Spectrum Disorder (ASD). This paper outlines our progression from initial, broad assessment using the Movement Assessment Battery for Children (M-ABC2) to subsequent targeted kinematic assessment. In particular, pronounced ASD impairment seen in the broad categories of manual dexterity and ball skills was found to be routed in specific difficulties on isolated tasks, which were translated into focused experimental assessment. Kinematic results from both subsequent studies highlight impaired use of perception-action coupling to guide, adapt and tailor movement to task demands, resulting in inflexible and rigid motor profiles. In particular difficulties with the use of temporal adaption are shown, with “hyperdexterity” witnessed in ballistic movement profiles, often at the cost of spatial accuracy and task performance. By linearly progressing from the use of a standardized assessment tool to targeted kinematic assessment, clear and defined links are drawn between measureable difficulties and underlying sensory-motor assessment. Results are specifically viewed in-light of perception-action coupling and its role in early infant development suggesting that rather than being “secondary” level impairment, sensory-motor problems may be fundamental in the progression of ASD. This logical and systematic process thus allows a further understanding into the potential root of observable motor problems in ASD; a vital step if underlying motor problems are to be considered a fundamental aspect of autism and allow a route of non-invasive preliminary diagnosis. PMID:23882194

Sensory-motor problems in Autism

Directory of Open Access Journals (Sweden)

Caroline eWhyatt

2013-07-01

Full Text Available Despite being largely characterised as a social and cognitive disorder, strong evidence indicates the presence of significant sensory-motor problems in Autism Spectrum Disorder (ASD. This paper outlines our progression from initial, broad assessment using the Movement Assessment Battery for Children (M-ABC2 to subsequent targeted kinematic assessment. In particular, pronounced ASD impairment seen in the broad categories of manual dexterity and ball skills was found to be routed in specific difficulties on isolated tasks, which were translated into focused experimental assessment. Kinematic results from both subsequent studies highlight impaired use of perception-action coupling to guide, adapt and tailor movement to task demands, resulting in inflexible and rigid motor profiles. In particular difficulties with the use of temporal adaption are shown, with hyperdexterity witnessed in ballistic movement profiles, often at the cost of spatial accuracy and task performance. By linearly progressing from the use of a standardised assessment tool to targeted kinematic assessment, clear and defined links are drawn between measureable difficulties and underlying sensory-motor assessment. Results are specifically viewed in-light of perception-action coupling and its role in early infant development suggesting that rather than being secondary level impairment, sensory-motor problems may be fundamental in the progression of ASD. This logical and systematic process thus allows a further understanding into the potential route of observable motor problems in ASD; a vital step if underlying motor problems are to be considered a fundamental aspect of autism and allow a route of non-invasive preliminary diagnosis.

Premorbid and illness-related social difficulties in eating disorders: an overview of the literature and treatment developments.

Science.gov (United States)

Cardi, Valentina; Tchanturia, Kate; Treasure, Janet

2018-01-17

Social difficulties in eating disorders can manifest as predisposing traits and premorbid difficulties, and/or as consequences of the illness. Objective The aim of this paper is to briefly review the evidence for social problems in people with eating disorders and to consider the literature on treatments that target these features. Method A narrative review of the literature was conducted. Results People with eating disorders often manifest traits, such as shyness, increased tendency to submissiveness and social comparison, and problems with peer relationships before illness onset. Further social difficulties occur as the illness develops, including impaired social cognition and increased threat sensitivity. All relationships with family, peers and therapists are compromised by these effects. Thus, social difficulties are both risk and maintaining factors of eating disorders and are suitable targets for interventions. Several forms of generic treatments (e.g. interpersonal psychotherapy, cognitive analytic therapy, focal psychodynamic therapy) have an interpersonal focus and show some efficacy. Guided self-management based on the cognitive interpersonal model of the illness and directed to both individuals and support persons have been found to improve outcomes for all parties. Adjunctive treatments that focus on specific social difficulties, such as Cognitive Remediation and Emotion Skills Training and Cognitive Bias Modification have been shown to have promise. Conclusion More work is needed to establish whether these approaches can improve on the rather disappointing outcomes that are attained by currently used treatments for eating disorders. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Understanding the Problems of Learning Mathematics.

Science.gov (United States)

Semilla-Dube, Lilia

1983-01-01

A model is being developed to categorize problems in teaching and learning mathematics. Categories include problems due to language difficulties, lack of prerequisite knowledge, and those related to the affective domain. This paper calls on individuals to share teaching and learning episodes; those submitted will then be compiled and categorized.…

Action-angle variables for the harmonic oscillator : ambiguity spin x duplication spin

International Nuclear Information System (INIS)

Oliveira, C.R. de; Malta, C.P.

1983-08-01

The difficulties of obtaining for the harmonic oscillator a well defined unitary transformation to action-angle variables were overcome by M. Moshinsky and T.H. Seligman through the introduction of a spinlike variable (ambiguity spin) from a classical point of view. The difficulty of defining a unitary phase operator for the harmonic oscillator was overcome by Roger G. Newton also through the introduction of a spinlike variable (named duplication spin by us) but within a quantum framework. The relation between the ambiguity spin and the duplication spin by introducing these two types of spins in the canonical transformation to action-angle variables is investigated. Doing this it is possible to obtain both well defined unitary transformation and phase operator. (Author) [pt

Psychological problems in children with hemiplegia: a European multicentre survey.

Science.gov (United States)

Parkes, J; White-Koning, M; McCullough, N; Colver, A

2009-06-01

To describe the prevalence and determinants of psychological problems in European children with hemiplegia. Cross-sectional survey. Home visits in nine European regions by research associates who administered standard questionnaires to parents. 279 children with hemiplegia aged 8-12 years were recruited from population-based case registers. Strengths and Difficulties Questionnaire comprising emotion, conduct, hyperactivity, peer problems and prosocial domains. An "impact score" (IS) measures the social and psychological impact of the child's difficulties. Children with hemiplegia had higher mean scores on the total difficulties score (TDS) compared with a normative sample (p70. Boys had an increased risk for conduct (OR 2.1, 95% CI 1.2 to 3.7) and hyperactivity disorders (OR 2.5, 95% CI 1.4 to 4.6). Poor self-esteem was associated with an increased risk for peer problems (OR 5.8, 95% CI 2.5 to 13.4) and poor prosocial skills (OR 7.5, 95% CI 2.4 to 23.2) compared with those with high self-esteem. Other determinants of psychological adjustment were impaired communication, severe pain and living with a single parent. Many of the psychological problems identified are amenable to treatment. Special attention should be given to those at highest risk of developing psychological difficulties.

Mastoidectomy: anatomical parameters x surgical difficulty

Directory of Open Access Journals (Sweden)

Pereira Júnior, Anastácio Rodrigues

2012-01-01

Full Text Available Introduction: The lowered temporal meninges and/ or anterior sigmoid sinus are contiditions that can determine surgical difficulties in performing mastoidectomy. Objective: To correlate in the tomography the extent of the prolapse of the sigmoid sinus and of temporal meninges with the surgical difficulty in the mastoidectomy. Method: The tomographic measurements of prolapse sigmoid and of temporal meninges were correlated with the presence or non-presence of the surgical difficulty observed during the mastoidectomy procedure in patients with ostomatoiditis chronic (n=30. Form of study: Contemporary cohort transverse. Results: In 10 patients were observed surgical difficulty distributed as: due to prolapse of the sigmoid sinus (n = 2 or temporal meninges prolapse (n = 7 or both (n = 1. In patients in which the surgical difficulty was due to sigmoid sinus prolapse, the tomography distance of the anterior border of the sigmoid sinus to posterior wall of external auditory canal was lower than 9 mm. In patients in which surgical difficulty was due to temporal meninges prolapse, the tomographic distance to the upper plane of the petrous bone was 7 mm. Conclusion: The computerized tomography distance between the temporal meninges and the upper plane of the petrous bone 7 mm and the distance of the anterior border of the sigmoid sinus to posterior wall of external auditory canal was lower than 9 mm are predictive to the surgical difficulties to perform mastoidectomy.

Sociodemographic Characteristics, Behavioral Problems, Parental Concerns and Children’s Strengths Reported by Parents

Directory of Open Access Journals (Sweden)

Deisy Ribas Emerich

Full Text Available Abstract: Parental report is essential to understand adaptive difficulties in childhood. The aim of the study was to identify concerns of parents and qualities of children reported by parents, as well as the association of these variables with sociodemographic factors and child behavior problems. Parents of 353 schoolchildren from three public schools and one private school took part in the study. Assessment of behavior problems and parental reports about concerns and children’s strengths were obtained from the Child Behavior Checklist - CBCL. We submitted parents’ answers to the open-ended questions in the CBCL to a lexical analysis with the IRAMUTEQ software. Results concerning ‘strengths’ were related to affective and social interaction, while ‘concerns’ were related to academic performance and prevention of behavior problems. We concluded that parent concerns are targets of preventive interventions in childhood, while child strengths reported by parents are skills that need to be developed, as they help in adaptive functioning.

Analysis of the efficiency of the linearization techniques for solving multi-objective linear fractional programming problems by goal programming

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Tunjo Perić

2017-01-01

Full Text Available This paper presents and analyzes the applicability of three linearization techniques used for solving multi-objective linear fractional programming problems using the goal programming method. The three linearization techniques are: (1 Taylor’s polynomial linearization approximation, (2 the method of variable change, and (3 a modification of the method of variable change proposed in [20]. All three linearization techniques are presented and analyzed in two variants: (a using the optimal value of the objective functions as the decision makers’ aspirations, and (b the decision makers’ aspirations are given by the decision makers. As the criteria for the analysis we use the efficiency of the obtained solutions and the difficulties the analyst comes upon in preparing the linearization models. To analyze the applicability of the linearization techniques incorporated in the linear goal programming method we use an example of a financial structure optimization problem.

[Public health infrastructure investment difficulties in Chile: concessions and public tenders].

Science.gov (United States)

Goyenechea, Matías

2016-05-12

This paper seeks to highlight the problems of gaps in health infrastructure in Chile, and to analyze the mechanisms by which it is provided. In Chile this is done in two ways: the first is through competitive bidding or sector-wide modality. The second way is through hospital concessions. Both mechanisms have had difficulties in recent years, which are reported. Finally, we propose ways to improve the provision of health infrastructure in Chile.

The relationship between EFL Teachers’ Attitudes towards CLT and Perceived Difficulties of Implementing CLT in Language Classes

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Mehrak Rahimi

2014-05-01

Full Text Available The present study investigated the relationship between EFL teachers’ attitudes towards CLT and perceived difficulties of implementing CLT in language classes. Two hundred and three EFL teachers participated in the study. Their attitudes towards CLT and their perceptions of the problems of implementing CLT were assessed by two questionnaires. The results of the descriptive statistics showed that EFL teachers had positive attitudes towards CLT in general and group work in communicative classes in particular. Further, while EFL teachers generally did not find much difficulty in implementing CLT in language classes, they found the difficulties the educational system creates as a major obstacle to use CLT. Moreover, CLT attitudes and perceived difficulties of CLT implementation were not found to be related; however, when subscales of CLT attitudes and perceived difficulties questionnaires were considered, three correlations were found to be statistically significant. Difficulties caused by students in communicative classes were found to be inversely and significantly related to (a attitudes to CLT as a whole (r=-.160, p<.05 and (b attitudes towards group/pair work in CLT (r=-.156, p<.05. Further, attitudes towards the role of teacher in a communicative class were found to be positively related to difficulties inherent in the CLT method itself (r= .181, p<.01.

Meanings Given to Algebraic Symbolism in Problem-Posing

Science.gov (United States)

Cañadas, María C.; Molina, Marta; del Río, Aurora

2018-01-01

Some errors in the learning of algebra suggest that students might have difficulties giving meaning to algebraic symbolism. In this paper, we use problem posing to analyze the students' capacity to assign meaning to algebraic symbolism and the difficulties that students encounter in this process, depending on the characteristics of the algebraic…

Dificuldades encontradas por médicos e enfermeiros na abordagem de problemas alimentares Difficulties found by physicians and nurses in approaching eating problems

Directory of Open Access Journals (Sweden)

Maria Cristina Faber Boog

1999-12-01

risk factors, among them, eating. The paper presents the results of a research that aimed to identify difficulties in this approach. The research involved eight physicians and nine nurses. Action-research method was used. The method involves service rendered, systematic observation, semi-structured interviews and return of the researcher's elaborated theory to the subjects. The technique employed was qualitative, based on the sociology of knowledge. The difficulties identified were: lack of theorical basis to analyze eating problems, lack of criteria to identify them, lack of parameters to distinguish eating problems from economic problems, lack of technical knowledge to approach eating problems, consideration of eating problems as immutable facts, necessity of working with standardized diets, conflicts between theoretical knowledge and routine habits and lack of knowledge of the nutritionist's role. The conclusion reminds the necessity of endeavoring efforts to improve nutrition teaching in medical and nursing courses, to develop methods that will allow the students to question eating facts, to develop researches in nutrition education field by improvement of teaching methods and to elucidate health professionals about the nutritionist's role in patient's nutrition education, creating conditions to interdisciplinary work. Considering the primary role of nutrition in health promotion, maintenance and recovery, it is essential to develop adequate learning adressed to health professionals about these subjects.

On the Etiology of Listening Difficulties in Noise Despite Clinically Normal Audiograms

Science.gov (United States)

2017-01-01

Many people with difficulties following conversations in noisy settings have “clinically normal” audiograms, that is, tone thresholds better than 20 dB HL from 0.1 to 8 kHz. This review summarizes the possible causes of such difficulties, and examines established as well as promising new psychoacoustic and electrophysiologic approaches to differentiate between them. Deficits at the level of the auditory periphery are possible even if thresholds remain around 0 dB HL, and become probable when they reach 10 to 20 dB HL. Extending the audiogram beyond 8 kHz can identify early signs of noise-induced trauma to the vulnerable basal turn of the cochlea, and might point to “hidden” losses at lower frequencies that could compromise speech reception in noise. Listening difficulties can also be a consequence of impaired central auditory processing, resulting from lesions affecting the auditory brainstem or cortex, or from abnormal patterns of sound input during developmental sensitive periods and even in adulthood. Such auditory processing disorders should be distinguished from (cognitive) linguistic deficits, and from problems with attention or working memory that may not be specific to the auditory modality. Improved diagnosis of the causes of listening difficulties in noise should lead to better treatment outcomes, by optimizing auditory training procedures to the specific deficits of individual patients, for example. PMID:28002080

The Study of Factors Influencing on Orthodontic Treatment Difficulty of Impacted Maxillary Canine with Cone Beam Computed Tomography

Directory of Open Access Journals (Sweden)

A.F. Miresmaeili

2012-10-01

Full Text Available Introduction & Objective: Maxillary canines are esthetically and functionally important, but patients with impacted maxillary canines are perceived to be more difficult and time-consuming to treat than the average orthodontic patient. The aim of this study was to define orthodontic Treatment Difficulty Index (TDI of impacted maxillary canine with CBCT according to experts' opinions.Materials & Methods: In this cross sectional study, nine variables in CBCT of thirty six consecutive patients with 50 impacted maxillary canines were measured using Dolphin 3D. The related 3D and 2D pictures and the measured data were uploaded on a website. Ten orthodontists were asked to judge the difficulty of bringing the impacted canine to occlusal plane from 1 to 10 (1 = easy, 10 = extremely difficult.Then, they were also asked to evaluate the effect of each variable on treatment from 1 to 5 (1= very low, 5= very high. Random effect linear regression was used in exploration stage and then simple linear regression was used for the application of the model.Results: The patients mean age was 19.08 ± 5.8 years. Mean clinical experience of examiners was 22.7 ±12.02 years. Three variables were deleted at exploration stage and two other in model application stage. Vertical distance to the occlusal plane (P=0.000, overlap in frontal view (P=0.000, angulations of the canine to the occlusal plan (P=0.029, dilacerations (P=0.000, and rotation (P=0.029 had a significant relationship with TDI.Conclusion: Treatment difficulty of impacted maxillary canines could be predicted quantitatively by measuring variables in CBCT.(Sci J Hamadan Univ Med Sci 2012;19(3:30-35

A cumulative risk factor model for early identification of academic difficulties in premature and low birth weight infants.

Science.gov (United States)

Roberts, G; Bellinger, D; McCormick, M C

2007-03-01

Premature and low birth weight children have a high prevalence of academic difficulties. This study examines a model comprised of cumulative risk factors that allows early identification of these difficulties. This is a secondary analysis of data from a large cohort of premature (mathematics. Potential predictor variables were categorized into 4 domains: sociodemographic, neonatal, maternal mental health and early childhood (ages 3 and 5). Regression analysis was used to create a model to predict reading and mathematics scores. Variables from all domains were significant in the model, predicting low achievement scores in reading (R (2) of 0.49, model p-value mathematics (R (2) of 0.44, model p-value intelligence, visual-motor skill and higher behavioral disturbance scores (early childhood). Lower mathematics scores were predicted by lower maternal education, income and age and Black or Hispanic race (sociodemographic); lower birth weight and higher head circumference (neonatal); lower maternal responsivity (maternal mental health); lower intelligence, visual-motor skill and higher behavioral disturbance scores (early childhood). Sequential early childhood risk factors in premature and LBW children lead to a cumulative risk for academic difficulties and can be used for early identification.

The problems of Visaginas town

International Nuclear Information System (INIS)

Schiurov, V.

1998-01-01

The problems of Visaginas are specific and, first of all, connected with the operation of the Ignalina nuclear power plant and cultural development of Visaginas ethnic minorities, lack of skilled specialists employed in different spheres. Some difficulties we have with the learning of the official language. A strong well-reasoned opinion of the scientists corresponds to our practical directions: the problems of the town of Visaginas are not only the problems of its inhabitants but also a composite part of the problems of the Ignalina nuclear power plant region. (author)

Pose and Solve Varignon Converse Problems

Science.gov (United States)

Contreras, José N.

2014-01-01

The activity of posing and solving problems can enrich learners' mathematical experiences because it fosters a spirit of inquisitiveness, cultivates their mathematical curiosity, and deepens their views of what it means to do mathematics. To achieve these goals, a mathematical problem needs to be at the appropriate level of difficulty,…

Diagnosis of Spasmodic Dysphonia Manifested by Swallowing Difficulty in Videofluoroscopic Swallowing Study

Science.gov (United States)

Yeo, Han Gyeol; Lee, Seong Jae; Hyun, Jung Keun

2015-01-01

Spasmodic dysphonia is defined as a focal laryngeal disorder characterized by dystonic spasms of the vocal cord during speech. We described a case of a 22-year-old male patient who presented complaining of idiopathic difficulty swallowing that suddenly developed 6 months ago. The patient also reported pharyngolaryngeal pain, throat discomfort, dyspnea, and voice change. Because laryngoscopy found no specific problems, an electrodiagnostic study and videofluoroscopic swallowing study (VFSS) were performed to find the cause of dysphagia. The VFSS revealed continuous twitch-like involuntary movement of the laryngeal muscle around the vocal folds. Then, he was diagnosed with spasmodic dysphonia by VFSS, auditory-perceptual voice analysis, and physical examination. So, we report the first case of spasmodic dysphonia accompanied with difficulty swallowing that was confirmed by VFSS. PMID:25932430

Characterisation of Sleep Problems in Children with Williams Syndrome

Science.gov (United States)

Annaz, Dagmara; Hill, Catherine M.; Ashworth, Anna; Holley, Simone; Karmiloff-Smith, Annette

2011-01-01

Sleep is critical to optimal daytime functioning, learning and general health. In children with established developmental disorders sleep difficulties may compound existing learning difficulties. The purpose of the present study was to evaluate the prevalence and syndrome specificity of sleep problems in Williams syndrome (WS), a…

Retrospective Basic Parent-Child Communication Difficulties and Risk of Depression in Deaf Adults.

Science.gov (United States)

Kushalnagar, Poorna; Bruce, Sheila; Sutton, Tina; Leigh, Irene W

2017-02-01

This paper describes the relationship between retrospective communication difficulties and current depressive symptomatology. A total of 143 deaf/hard-of-hearing late adolescents and adults (64 % White; 55 % female) completed questionnaires related to parent communication, language history and current psychological functioning. Logistic regression models were used to estimate the likelihood of having depression that is associated with understanding parents' communication after controlling for gender, hearing level, and language history. Significant odds ratio indicated that the difficulties in understanding basic communication with parents increased the odds of depression symptomatology. The odds ratio indicates that when holding all other variables constant, the odds of reporting depression were at least 8 times higher for those who reported being able to understand some to none of what the same-sex parent said. For the different-gender parent, only the mother's communication with the male individual was associated with depression. Although our study findings suggest that DHH men and women with history of communication difficulties at home are at risk for depression in adulthood, they do not provide information on the causal mechanisms linking communication difficulties early in life and depression later in life. Greater attention should be given to promoting healthy communication between DHH girls and their mothers as well as DHH boys and their fathers, which might reduce the impact on later emergence of depression in the DHH individual.

The Importance of Sleep: Attentional Problems in School-Aged Children With Down Syndrome and Williams Syndrome.

Science.gov (United States)

Ashworth, Anna; Hill, Catherine M; Karmiloff-Smith, Annette; Dimitriou, Dagmara

2015-01-01

In typically developing (TD) children, sleep problems have been associated with day-time attentional difficulties. Children with developmental disabilities often suffer with sleep and attention problems, yet their relationship is poorly understood. The present study investigated this association in school-aged children with Down syndrome (DS) and Williams syndrome (WS). Actigraphy and pulse oximetry assessed sleep and sleep-disordered breathing respectively, and attention was tested using a novel visual Continuous Performance Task (CPT).Attentional deficits were evident in both disorder groups. In the TD group, higher scores on the CPT were related to better sleep quality, higher oxyhemoglobin saturation (SpO2), and fewer desaturation events. Sleep quality, duration, and SpO2 variables were not related to CPT performance for children with DS and WS.

Profiles of Emergent Literacy Skills among Preschool Children Who Are at Risk for Academic Difficulties

Science.gov (United States)

Cabell, Sonia Q.; Justice, Laura M.; Konold, Timothy R.; McGinty, Anita S.

2011-01-01

The purpose of this study was to explore patterns of within-group variability in the emergent literacy skills of preschoolers who are at risk for academic difficulties. We used the person-centered approach of cluster analysis to identify profiles of emergent literacy skills, taking into account both oral language and code-related skills.…

Influence of Number Size, Problem Structure and Response Mode on Children's Solutions of Multiplication Word Problems.

Science.gov (United States)

De Corte, E.; And Others

One important finding from recent research on multiplication word problems is that children's performances are strongly affected by the nature of the multiplier (whether it is an integer, decimal larger than 1 or a decimal smaller than 1). On the other hand, the size of the multiplicand has little or no effect on problem difficulty. The aim of the…

STUDENTS’ DIFFICULTIES IN BIOCHEMISTRY LEARNING ANALYZED THROUGH AN ON LINE ACADEMIC DROP-IN CENTER

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F. Schoenmaker

2007-05-01

Full Text Available The biochemistry discipline integrates the curriculum of all graduation courses onthe Biological Area and is a basis for other disciplines. The students’ difficulties inthis discipline are already widely recognized. To investigate these difficulties, wecreated a drop-in on line service that has two purposes: (1 To give support tostudents’ learning by answering their questions and solving their problemswhenever they appear and (2 to analyze the questions presented, as a strategy todiagnose the most prevalent difficulties. After two semesters of this service on line,217 questions were received and answered. There were few conceptual questionsbeing the majority related to problems and exercises. The most frequent questionsdealt with cell metabolism (54,4%, mainly lipid metabolism and aerobicmetabolism; basic concepts (11,5% such as about amino acids and buffer, proteinstructure (8,3% and enzymes (7,8%. These percentages are correlated to thenumber of hours dedicated to each subjects in the disciplines. The main difficultiesfounded were: integration of metabolic processes in different tissues, induction ofenergy reserve oxidation, reciprocal regulation between glycolysis andgluconeogenesis. We suppose that the lack of laboratory practice difficults thelearning of basic concepts. A more in-deep analysis will be necessary toinvestigate the causes of the pointed difficulties.

ADHD Expressive Writing Difficulties of ADHD Children: When Good Declarative Knowledge Is Not Sufficient

Science.gov (United States)

Re, Anna Maria; Cornoldi, Cesare

2010-01-01

A large body of evidence shows that many of the academic difficulties Attention Deficit Hyperactivity Disorder (ADHD) children have may be related to their problems in executive control. However, the particular case of expressive writing has not been deeply explored. The present study examines the typical school exercise of writing a letter.…

ADULTS’ LEARNING IN A MULTILEVEL GROUP: DIFFICULTIES AND PROSPECTS

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Salamatina, I.I.

2017-12-01

Full Text Available One of the necessary conditions of modernization of higher education system of the Russian Federation is to increase the level of academic mobility of the teaching community of Russian Universities. To solve this problem in 2014 in the State University of Humanities and Social Studies it was made the decision to organize the biennial English language courses for teachers of non-linguistic specialties, to enhance their level of proficiency. The greatest difficulty in teaching was because of different levels of language proficiency, so the teacher had to develop an effective methodology of teaching English for different levels of students.

Radiation streaming: the continuing problem of shield design

International Nuclear Information System (INIS)

Avery, A.F.

1977-01-01

The practical problems of shield design are reviewed and the major difficulties are shown to be those associated with streaming problems. The situations in which streaming occurs in various types of reactor are described including LMFBR's and fusion devices, and examples are given of ways in which the problems have been solved

Effects of Kanjertraining (Topper Training) on Emotional Problems, Behavioural Problems and Classroom Climate

NARCIS (Netherlands)

Vliek, L.

2015-01-01

Reducing difficulties in social interactions and negative classroom climate at an early age may prevent escalation into severe problems that are harder to treat and save society from the associated costs and risks. Topper Training (Kanjertraining in Dutch) has been widely implemented in Dutch

An ontological framework for model-based problem-solving

NARCIS (Netherlands)

Scholten, H.; Beulens, A.J.M.

2012-01-01

Multidisciplinary projects to solve real world problems of increasing complexity are more and more plagued by obstacles such as miscommunication between modellers with different disciplinary backgrounds and bad modelling practices. To tackle these difficulties, a body of knowledge on problems, on

A case-control study of the difficulties in daily functioning experienced by children with depressive disorder.

Science.gov (United States)

Usami, Masahide; Iwadare, Yoshitaka; Watanabe, Kyota; Ushijima, Hirokage; Kodaira, Masaki; Okada, Takashi; Sasayama, Daimei; Sugiyama, Nobuhiro; Saito, Kazuhiko

2015-07-01

The parent-assessed children-with-difficulties questionnaire (Questionnaire-Children with Difficulties; QCD) is designed to evaluate a child׳s difficulties in functioning during specific periods of the day. This study aimed to use the QCD to evaluate the difficulties in daily functioning experienced by children with depressive disorders. A case-control design was used. The cases comprised 90 junior high school students with depressive disorder, whereas a community sample of 363 junior high school students was enrolled as controls. Behaviors were assessed using the QCD, Depression Self-Rating Scale (DSRS), Tokyo Autistic Behavior Scale (TABS), attention deficit hyperactivity disorder-rating scale (ADHD-RS), and Oppositional Defiant Behavior Inventory (ODBI). We then analyzed the effects of sex and diagnosis on the QCD scores as well as the correlation coefficients between the QCD and the other questionnaires. We included 90 cases (33 boys, 57 girls) with depressive disorders and 363 controls (180 boys, 183 girls). The QCD scores for the children with depressive disorders were significantly lower compared with those from the community sample (Pdepressive disorders and truancy problems than for those with depressive disorders alone (Pdepressive disorders experienced greater difficulties in completing basic daily activities compared with community controls. These difficulties were dependent on sex, symptoms, and the time of day. The use of QCD to assess children with depressive disorders enables clinicians to clarify the time periods at which the children face difficulties. Copyright © 2015 Elsevier B.V. All rights reserved.

A Hamiltonian-based derivation of Scaled Boundary Finite Element Method for elasticity problems

International Nuclear Information System (INIS)

Hu Zhiqiang; Lin Gao; Wang Yi; Liu Jun

2010-01-01

The Scaled Boundary Finite Method (SBFEM) is a semi-analytical solution approach for solving partial differential equation. For problem in elasticity, the governing equations can be obtained by mechanically based formulation, Scaled-boundary-transformation-based formulation and principle of virtual work. The governing equations are described in the frame of Lagrange system and the unknowns are displacements. But in the solution procedure, the auxiliary variables are introduced and the equations are solved in the state space. Based on the observation that the duality system to solve elastic problem proposed by W.X. Zhong is similar to the above solution approach, the discretization of the SBFEM and the duality system are combined to derive the governing equations in the Hamilton system by introducing the dual variables in this paper. The Precise Integration Method (PIM) used in Duality system is also an efficient method for the solution of the governing equations of SBFEM in displacement and boundary stiffness matrix especially for the case which results some numerical difficulties in the usually uses the eigenvalue method. Numerical examples are used to demonstrate the validity and effectiveness of the PIM for solution of boundary static stiffness.

Sleep problems of adolescents: A detailed survey.

Science.gov (United States)

Muluk, Nuray Bayar; Bulbul, Selda Fatma; Turğut, Mahmut; Ağirtaş, Gülşah

2015-06-01

We investigated the sleep problems and sleep habits of adolescents at three public primary schools and two high schools. Our study included 428 Turkish school children (244 girls and 184 boys). We used a questionnaire to determine the time they went to sleep at night; waking time in the morning; incidence of nightmares, snoring, daytime sleepiness, and intrafamilial physical trauma; concentration difficulty in class; and school success. The students were divided into age-related groups (group 1 = 11 to 13 years of age; group 2 = 14 to 15 years; group 3 = 16 to 18 years). The time they went to sleep was mostly between 10 and 11 p.m. in groups 1 and 2, and 11 to 12 p.m. in group 3. Difficulty in falling asleep was reported by 16.8 to 19.6% of the students in the three groups. Difficulty in waking up in the morning was reported by 12.7% of group 1, 16.0% of group 2, and 16.8% of group 3. Snoring was present in 12.1% of females and 22.0% of males. The occurrence of one nightmare in the preceding 3 months was reported by 11.3% of the students; 17.9% of the students reported having nightmares several times. Daytime sleepiness was present in 65.1%, and concentration difficulty was present in 56.8% of the students. We conclude that difficulty in falling asleep, snoring, and daytime sleepiness may be seen in adolescents who are in both primary and high schools. Watching inappropriate programs and movies on television and intrafamilial physical trauma may cause nightmares and sleeping problems in these adolescents. Students and families should be educated about the importance of sleep in academic performance. Countries' public health policies should address sleep problems and related educational activities.

Beyond Epistemological Deficits: Dynamic explanations of engineering students' difficulties with mathematical sense-making

Science.gov (United States)

Gupta, Ayush; Elby, Andrew

2011-12-01

Researchers have argued against deficit-based explanations of students' difficulties with mathematical sense-making, pointing instead to factors such as epistemology. Students' beliefs about knowledge and learning can hinder the activation and integration of productive knowledge they have. Such explanations, however, risk falling into a 'deficit trap'-substituting a concepts/skills deficit with an epistemological one. Our interview-based case study of a freshman engineering major, 'Jim,' explains his difficulty solving a physics problem (on hydrostatic pressure) in terms of his epistemology, but avoids a deficit trap by modeling the dynamics of his epistemological stabilities and shifts in terms of fine-grained cognitive elements that include the seeds of epistemological expertise. Specifically, during a problem-solving episode in the interview, Jim reaches and sticks with an incorrect answer that violates common sense. We show that Jim has all the mathematical skills and physics knowledge he would need to resolve the contradiction. We argue that his difficulty doing so stems in part from his epistemological views that (i) physics equations are much more trustworthy than everyday reasoning, and (ii) physics equations do not express meaning that tractably connects to common sense. For these reasons, he does not view reconciling between common sense and formalism as either necessary or plausible to accomplish. But Jim's in-the-moment shift to a more sophisticated epistemological stance highlights the seeds of epistemological expertise that were present all along: he does see common sense as connected to formalism (though not always tractably so), and in some circumstances, this connection is both salient and valued.

University Students with Reading Difficulties: Do Perceived Supports and Comorbid Difficulties Predict Well-being and GPA?

Science.gov (United States)

Stack-Cutler, Holly L.; Parrila, Rauno K.; Torppa, Minna

2016-01-01

We examined the impact of the number of comorbid difficulties, social support, and community support on life satisfaction and academic achievement among 120 university students or recent graduates with self-reported reading difficulties. Participants completed a questionnaire assessing perceived social support, perceived community support, the…

Uncertainty and the difficulty of thinking through disjunctions.

Science.gov (United States)

Shafir, E

1994-01-01

This paper considers the relationship between decision under uncertainty and thinking through disjunctions. Decision situations that lead to violations of Savage's sure-thing principle are examined, and a variety of simple reasoning problems that often generate confusion and error are reviewed. The common difficulty is attributed to people's reluctance to think through disjunctions. Instead of hypothetically traveling through the branches of a decision tree, it is suggested, people suspend judgement and remain at the node. This interpretation is applied to instances of decision making, information search, deductive and inductive reasoning, probabilistic judgement, games, puzzles and paradoxes. Some implications of the reluctance to think through disjunctions, as well as potential corrective procedures, are discussed.

The variability problem of normal human walking

DEFF Research Database (Denmark)

Simonsen, Erik B; Alkjær, Tine

2012-01-01

Previous investigations have suggested considerable inter-individual variability in the time course pattern of net joint moments during normal human walking, although the limited sample sizes precluded statistical analyses. The purpose of the present study was to obtain joint moment patterns from...... a group of normal subjects and to test whether or not the expected differences would prove to be statistically significant. Fifteen healthy male subjects were recorded on video while they walked across two force platforms. Ten kinematic and kinetic parameters were selected and input to a statistical...... cluster analysis to determine whether or not the 15 subjects could be divided into different 'families' (clusters) of walking strategy. The net joint moments showed a variability corroborating earlier reports. The cluster analysis showed that the 15 subjects could be grouped into two clusters of 5 and 10...

Analysis of Critical Factors and Difficulties in Maintaining Historical Building - A Current Implementation

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Baharuddin M.N.

2014-01-01

Full Text Available Historic buildingis one of the highly valuable assets to the country especially in a way to shows its history for the next generation instead to make a profit through the excellent promotion in tourism purpose.The Malaysian Government has allocated a huge of financial support in order to conserve and preserve the historic building. However, the majority of the historic building is still in ‘poor’ condition without any improvement regarding to the pro-active approach.This paper presents part of this research which investigates the key components consists of issues and difficulties in term of critical factors. The findings reveal that there are several difficulties in maintaining a historic building. The identification of key components will facilitate the stakeholders to focus on the variable and resources to make the success in maintaining and managing the historic building.

On the measurement of movement difficulty in the standard approach to Fitts' law.

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Yves Guiard

Full Text Available Fitts' law is an empirical rule of thumb which predicts the time it takes people, under time pressure, to reach with some pointer a target of width W located at a distance D. It has been traditionally assumed that the predictor of movement time must be some mathematical transform of the quotient of D/W, called the index of difficulty (ID of the movement task. We ask about the scale of measurement involved in this independent variable. We show that because there is no such thing as a zero-difficulty movement, the IDs of the literature run on non-ratio scales of measurement. One notable consequence is that, contrary to a widespread belief, the value of the y-intercept of Fitts' law is uninterpretable. To improve the traditional Fitts paradigm, we suggest grounding difficulty on relative target tolerance W/D, which has a physical zero, unlike relative target distance D/W. If no one can explain what is meant by a zero-difficulty movement task, everyone can understand what is meant by a target layout whose relative tolerance W/D is zero, and hence whose relative intolerance 1-W/D is 1 or 100%. We use the data of Fitts' famous tapping experiment to illustrate these points. Beyond the scale of measurement issue, there is reason to doubt that task difficulty is the right object to try to measure in basic research on Fitts' law, target layout manipulations having never provided users of the traditional Fitts paradigm with satisfactory control over the variations of the speed and accuracy of movements. We advocate the trade-off paradigm, a recently proposed alternative, which is immune to this criticism.

Process-based Assignment-Setting Change for Support of Overcoming Bottlenecks in Learning by Problem-Posing in Arithmetic Word Problems

Science.gov (United States)

Supianto, A. A.; Hayashi, Y.; Hirashima, T.

2017-02-01

Problem-posing is well known as an effective activity to learn problem-solving methods. Monsakun is an interactive problem-posing learning environment to facilitate arithmetic word problems learning for one operation of addition and subtraction. The characteristic of Monsakun is problem-posing as sentence-integration that lets learners make a problem of three sentences. Monsakun provides learners with five or six sentences including dummies, which are designed through careful considerations by an expert teacher as a meaningful distraction to the learners in order to learn the structure of arithmetic word problems. The results of the practical use of Monsakun in elementary schools show that many learners have difficulties in arranging the proper answer at the high level of assignments. The analysis of the problem-posing process of such learners found that their misconception of arithmetic word problems causes impasses in their thinking and mislead them to use dummies. This study proposes a method of changing assignments as a support for overcoming bottlenecks of thinking. In Monsakun, the bottlenecks are often detected as a frequently repeated use of a specific dummy. If such dummy can be detected, it is the key factor to support learners to overcome their difficulty. This paper discusses how to detect the bottlenecks and to realize such support in learning by problem-posing.

Externalizing Behavior Problems during Adolescence: An Ecological Perspective

Science.gov (United States)

White, Rachel; Renk, Kimberly

2012-01-01

Given the ramifications of difficulties related to externalizing behavior problems, the present study examined the relationships among adolescents' externalizing behavior problems, characteristics of adolescents' families, their perceived neighborhood support, and their acculturation. As part of this study, a culturally diverse sample of…

About hidden influence of predictor variables: Suppressor and mediator variables

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Milovanović Boško

2013-01-01

Full Text Available In this paper procedure for researching hidden influence of predictor variables in regression models and depicting suppressor variables and mediator variables is shown. It is also shown that detection of suppressor variables and mediator variables could provide refined information about the research problem. As an example for applying this procedure, relation between Atlantic atmospheric centers and air temperature and precipitation amount in Serbia is chosen. [Projekat Ministarstva nauke Republike Srbije, br. 47007

Problems in equilibrium theory

CERN Document Server

Aliprantis, Charalambos D

1996-01-01

In studying General Equilibrium Theory the student must master first the theory and then apply it to solve problems. At the graduate level there is no book devoted exclusively to teaching problem solving. This book teaches for the first time the basic methods of proof and problem solving in General Equilibrium Theory. The problems cover the entire spectrum of difficulty; some are routine, some require a good grasp of the material involved, and some are exceptionally challenging. The book presents complete solutions to two hundred problems. In searching for the basic required techniques, the student will find a wealth of new material incorporated into the solutions. The student is challenged to produce solutions which are different from the ones presented in the book.

A Framework for Understanding the Patterns of Student Difficulties in Quantum Mechanics

Science.gov (United States)

Singh, Chandralekha

2015-04-01

Compared with introductory physics, relatively little is known about the development of expertise in advanced physics courses, especially in the case of quantum mechanics. We describe a theoretical framework for understanding the patterns of student reasoning difficulties and how students develop expertise in quantum mechanics. The framework posits that the challenges many students face in developing expertise in quantum mechanics are analogous to the challenges introductory students face in developing expertise in introductory classical mechanics. This framework incorporates the effects of diversity in students' prior preparation, goals and motivation for taking upper-level physics courses in general as well as the ``paradigm shift'' from classical mechanics to quantum mechanics. The framework is based on empirical investigations demonstrating that the patterns of reasoning, problem-solving, and self-monitoring difficulties in quantum mechanics bear a striking resemblance to those found in introductory classical mechanics. Examples from research in quantum mechanics and introductory classical mechanics will be discussed to illustrate how the patterns of difficulties are analogous as students learn to unpack the respective principles and grasp the formalism in each knowledge domain during the development of expertise. Embracing such a theoretical framework and contemplating the parallels between the difficulties in these two knowledge domains can enable researchers to leverage the extensive literature for introductory physics education research to guide the design of teaching and learning tools for helping students develop expertise in quantum mechanics. Support from the National Science Foundation is gratefully acknowledged.

The Music of Mathematics: Toward a New Problem Typology

Science.gov (United States)

Quarfoot, David

Halmos (1980) once described problems and their solutions as "the heart of mathematics". Following this line of thinking, one might naturally ask: "What, then, is the heart of problems?". In this work, I attempt to answer this question using techniques from statistics, information visualization, and machine learning. I begin the journey by cataloging the features of problems delineated by the mathematics and mathematics education communities. These dimensions are explored in a large data set of students working thousands of problems at the Art of Problem Solving, an online company that provides adaptive mathematical training for students around the world. This analysis is able to concretely show how the fabric of mathematical problems changes across different subjects, difficulty levels, and students. Furthermore, it locates problems that stand out in the crowd -- those that synergize cognitive engagement, learning, and difficulty. This quantitatively-heavy side of the dissertation is partnered with a qualitatively-inspired portion that involves human scoring of 105 problems and their solutions. In this setting, I am able to capture elusive features of mathematical problems and derive a fuller picture of the space of mathematical problems. Using correlation matrices, principal components analysis, and clustering techniques, I explore the relationships among those features frequently discussed in mathematics problems (e.g., difficulty, creativity, novelty, affective engagement, authenticity). Along the way, I define a new set of uncorrelated features in problems and use these as the basis for a New Mathematical Problem Typology (NMPT). Grounded in the terminology of classical music, the NMPT works to quickly convey the essence and value of a problem, just as terms like "etude" and "mazurka" do for musicians. Taken together, these quantitative and qualitative analyses seek to terraform the landscape of mathematical problems and, concomitantly, the current thinking

Examining of the social problem solving skills in preschool children in terms of different variables

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Şuheda Bozkurt Yükçü

2017-09-01

Full Text Available The purpose of this research is to examine preschool children's social problem solving skills in terms of various variables. The population of the study consisted of parents and their children between the ages four-six years who attend independent kindergartens located in Çankaya county of Ankara during the 2015-2016 academic year. The sample of the study selected by simple random sampling method, consisted of 240 parents and their children between the ages four-six years who attend independent kindergartens located in Çankaya counties of Ankara during the 2015-2016 academic year. In this study conducted by descriptive screenning model, General Information Form and Wally Child Social Problem Solving Detective Game Test were used. Kruskal Wallis-H Test, Independent Groups T Test, One Way Anova were used to analyze of data. According to the results of this study, social problem solving skills of children differ based on child’s age but do not differ based on gender, number of siblings, montly income, parents’s age, educational status and working status. The findings were discussed and interpreted within the scope of the literature.

Los problemas evolutivos de coordinación en la adolescencia: Análisis de una dificultad oculta. Developmental coordination problems in the adolescence: analisys of a hidden difficulty.

Directory of Open Access Journals (Sweden)

Ruiz Pérez , Luis Miguel

2006-04-01

Full Text Available ResumenEl presente artículo realiza un análisis de los problemas evolutivos de coordinación motriz en la edad escolar, un asunto que ha recibido una escasa atención en los ámbitos educativos españoles. La existencia de estas dificultades de estos adolescentes tiene su mayor expresión más relevante en las sesiones de educación física, de aprendizaje deportivo o en los juegos, ha provocado una gran preocupación en los países de nuestro entorno y el desarrollo de programas de intervención que palie esta condición y la remedie. Más allá de las relevancias que se puedan otorgar a las diferentes materias del currículo escolar, la competencia motriz es un elemento imprescindible para favorecer un estilo de vida saludable entre los escolares de la educación secundaria, desvelar al existencia de esta dificultad es un primer paso en esta dirección.AbstractThe objective of this article has been to analyze developmental coordination problems in school ages, a matter that has received a short attention among educators in our country. The clear expression of this difficulty is in the physical education and sport classes. Many countries have begun to study and analyze this problem worried about the increased incidence of it, and have developed intervention programmes in order to improve the motor competence of these children. Physical education has the objective of developing of motor competence in all our secondary school children and promote a healthy life style among them, to uncover this hidden difficulty is a necessary step in this direction.

The Relationship between Sensory Processing Difficulties and Behaviour in Children Aged 5-9 Who Are at Risk of Developing Conduct Disorder

Science.gov (United States)

Fox, Cara; Snow, Pamela C.; Holland, Kerry

2014-01-01

Behavioural problems in childhood are common, with significant and wide-ranging implications for individuals, families and the community. There is some evidence that sensory processing difficulties are associated with behavioural problems in children with disabilities such as autism spectrum disorders (ASDs) and attention-deficit/hyperactivity…

Mechanical problem-solving strategies in Alzheimer's disease and semantic dementia.

Science.gov (United States)

Lesourd, Mathieu; Baumard, Josselin; Jarry, Christophe; Etcharry-Bouyx, Frédérique; Belliard, Serge; Moreaud, Olivier; Croisile, Bernard; Chauviré, Valérie; Granjon, Marine; Le Gall, Didier; Osiurak, François

2016-07-01

The goal of this study was to explore whether the tool-use disorders observed in Alzheimer's disease (AD) and semantic dementia (SD) are of the same nature as those observed in left brain-damaged (LBD) patients. Recent evidence indicates that LBD patients with apraxia of tool use encounter difficulties in solving mechanical problems, characterized by the absence of specific strategies. This pattern may show the presence of impaired mechanical knowledge, critical for both familiar and novel tool use. So, we explored the strategies followed by AD and SD patients in mechanical problem-solving tasks in order to determine whether mechanical knowledge is also impaired in these patients. We used a mechanical problem-solving task in both choice (i.e., several tools were proposed) and no-choice (i.e., only 1 tool was proposed) conditions. We analyzed quantitative data and strategy profiles. AD patients but not SD patients met difficulties in solving mechanical problem-solving tasks. However, the key finding is that AD patients, despite their difficulties, showed strategy profiles that are similar to that of SD patients or controls. Moreover, AD patients exhibited a strategy profile distinct from the one previously observed in LBD patients. Those observations lead us to consider that difficulties met by AD patients to solve mechanical problems or even to use familiar tools may not be caused by mechanical knowledge impairment per se. In broad terms, what we call apraxia of tool use in AD is certainly not the same as apraxia of tool use observed in LBD patients. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Heuristic methods using grasp, path relinking and variable neighborhood search for the clustered traveling salesman problem

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Mário Mestria

2013-08-01

Full Text Available The Clustered Traveling Salesman Problem (CTSP is a generalization of the Traveling Salesman Problem (TSP in which the set of vertices is partitioned into disjoint clusters and objective is to find a minimum cost Hamiltonian cycle such that the vertices of each cluster are visited contiguously. The CTSP is NP-hard and, in this context, we are proposed heuristic methods for the CTSP using GRASP, Path Relinking and Variable Neighborhood Descent (VND. The heuristic methods were tested using Euclidean instances with up to 2000 vertices and clusters varying between 4 to 150 vertices. The computational tests were performed to compare the performance of the heuristic methods with an exact algorithm using the Parallel CPLEX software. The computational results showed that the hybrid heuristic method using VND outperforms other heuristic methods.

Difficulties implementing a mental health guideline: an exploratory investigation using psychological theory

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Eccles Martin P

2007-03-01

to these domains were unlikely to constitute difficulties in implementation. 'Environmental context and resources' was the lowest scoring domain, with 'Emotion' scoring the second lowest, suggesting that these were likely to be areas for considering intervention. The two main resources identified as problems were time and training. The emotions that appeared to potentially influence the offer of family therapy were self-doubt and fear. Conclusion This exploratory study demonstrates an approach to developing a theoretical understanding of implementation difficulties.

Trajectories of older adults' hearing difficulties: examining the influence of health behaviors and social activity over 10 years.

Science.gov (United States)

Heine, Chyrisse; Browning, Colette; Cowlishaw, Sean; Kendig, Hal

2013-10-01

The aims of the present study were to describe the trajectories of self-reported hearing difficulties over time, and evaluate the impacts of age, sex, lifestyle factors and social activity, in explaining individual differences in patterns of change over time. As part of the Melbourne Longitudinal Studies on Healthy Aging (MELSHA) Program, the hearing status of 947 adults aged 65 years and older, across five measurement periods (over 10 years), were analyzed using Latent Growth Curve Modeling analysis. A multidimensional survey was also administered, which included questions relating to sociodemographic variables, self-reported hearing difficulties, nutrition, smoking habits and level of social activity. Although there was a general increase in hearing difficulties over time, older age, poor nutrition, a lifetime of smoking and increased social activity predicted more rapid increases in hearing difficulty over time. Findings support the importance of lifestyle factors in reducing the rate of perceived hearing difficulties in older people, and provide further evidence of the links between lifestyle and sensory loss in older people. Poor nutrition and smoking are areas that both clinicians and public health professionals should address in their work with older people. © 2013 Japan Geriatrics Society.

Difficulties faced by family physicians in primary health care centers in Jeddah, Saudi Arabia

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Sahar H Mumenah

2015-01-01

Full Text Available Aim: The aim was to determine the difficulties faced by family physicians, and compare how satisfied those working with the Ministry of Health (MOH are with their counterparts who work at some selected non-MOH hospitals. Methods: An analytical, cross-sectional study was conducted at King Abdulaziz University Hospital, King Faisal Specialist Hospital and Research Center (KFSH and RC, and 40 MOH primary health care centers across Jeddah. A structured multi-item questionnaire was used to collect demographic data and information on the difficulties family physicians face. The physicians′ level of satisfaction and how it was affected by the difficulties was assessed. Results: Women constituted 71.9% of the sample. Problems with transportation formed one of the main difficulties encountered by physicians. Compared to non-MOH physician, a significantly higher proportion of MOH physicians reported unavailability of radiology technicians (P = 0.011 and radiologists (P < 0.001, absence of the internet and computer access (P < 0.001, unavailability of laboratory services (P = 0.004, reagents (P = 0.001, X-ray equipment (P = 0.027, ultrasound equipment (P < 0.001, an electronic medical records system (P < 0.001, insufficient laboratory tests (P = 0.0001, and poor building maintenance (P < 0.001. Family physicians with the MOH were less satisfied with their jobs compared with non-MOH physicians (P = 0.032. Conclusion: MOH family physicians encountered difficulties relating to staff, services, and infrastructure, which consequently affected their level of satisfaction.

Multi-Objective Flexible Flow Shop Scheduling Problem Considering Variable Processing Time due to Renewable Energy

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Xiuli Wu

2018-03-01

Full Text Available Renewable energy is an alternative to non-renewable energy to reduce the carbon footprint of manufacturing systems. Finding out how to make an alternative energy-efficient scheduling solution when renewable and non-renewable energy drives production is of great importance. In this paper, a multi-objective flexible flow shop scheduling problem that considers variable processing time due to renewable energy (MFFSP-VPTRE is studied. First, the optimization model of the MFFSP-VPTRE is formulated considering the periodicity of renewable energy and the limitations of energy storage capacity. Then, a hybrid non-dominated sorting genetic algorithm with variable local search (HNSGA-II is proposed to solve the MFFSP-VPTRE. An operation and machine-based encoding method is employed. A low-carbon scheduling algorithm is presented. Besides the crossover and mutation, a variable local search is used to improve the offspring’s Pareto set. The offspring and the parents are combined and those that dominate more are selected to continue evolving. Finally, two groups of experiments are carried out. The results show that the low-carbon scheduling algorithm can effectively reduce the carbon footprint under the premise of makespan optimization and the HNSGA-II outperforms the traditional NSGA-II and can solve the MFFSP-VPTRE effectively and efficiently.

A theoretical and experimental investigation of creep problems with variable temperature

International Nuclear Information System (INIS)

Ponter, A.R.S.; Walter, M.H.

1975-01-01

This paper attempts to delineate the principal features of the behavior when load level are maintained at those appropriate to many design situations and when the temperature and loading histories are cyclic with relatively short cycle times. It is concerned with structures which accumulate creep strains of less than 1% per year and have cycle times of the order of a few days at most. In the first section the behavior of a few simple structures are investigated for spatially varying temperature fields which remain constant in time. Adopting an appropriate form of Norton's Law we show that the deformation of the structure may be related to a single reference material test conducted at a reference stress and a reference temperature, which is independent of material constants, thereby providing a generalization of the reference stress method for isothermal structures. A sequence of experiments on a simple beam structure indicates that the co-relation between structural behavior and material tests provides an acceptably accurate design method. The last section discussed a preliminary experimental investigation of a two-bar structure subject to variable temperature. It is shown that the residual stress field varies quite slowly in time and remains effectively constant after a few cycles. The theoretical consequences of the results are discussed and it is shown that constitutive relationships with differing physical assumptions can yield quite sharply contrasting deformation rates. The results of the paper show that the behavior of structures subject to a time constant temperature distribution may be related to material behavior without difficulty. When temperature and load vary with time, the more important feature of the structural behavior may be understood, although certain features of the material behavior remain ill-defined

Influence of Surface Roughness Spatial Variability and Temporal Dynamics on the Retrieval of Soil Moisture from SAR Observations

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Jesús Álvarez-Mozos

2009-01-01

Full Text Available Radar-based surface soil moisture retrieval has been subject of intense research during the last decades. However, several difficulties hamper the operational estimation of soil moisture based on currently available spaceborne sensors. The main difficulty experienced so far results from the strong influence of other surface characteristics, mainly roughness, on the backscattering coefficient, which hinders the soil moisture inversion. This is especially true for single configuration observations where the solution to the surface backscattering problem is ill-posed. Over agricultural areas cultivated with winter cereal crops, roughness can be assumed to remain constant along the growing cycle allowing the use of simplified approaches that facilitate the estimation of the moisture content of soils. However, the field scale spatial variability and temporal variations of roughness can introduce errors in the estimation of soil moisture that are difficult to evaluate. The objective of this study is to assess the impact of roughness spatial variability and roughness temporal variations on the retrieval of soil moisture from radar observations. A series of laser profilometer measurements were performed over several fields in an experimental watershed from September 2004 to March 2005. The influence of the observed roughness variability and its temporal variations on the retrieval of soil moisture is studied using simulations performed with the Integral Equation Model, considering different sensor configurations. Results show that both field scale roughness spatial variability and its temporal variations are aspects that need to be taken into account, since they can introduce large errors on the retrieved soil moisture values.

The stigma of mental health problems in the military.

Science.gov (United States)

Greene-Shortridge, Tiffany M; Britt, Thomas W; Castro, Carl Andrew

2007-02-01

The present review addresses the perceived stigma associated with admitting a mental health problem and seeking help for that problem in the military. Evidence regarding the public stigma associated with mental disorders is reviewed, indicating that the public generally holds negative stereotypes toward individuals with psychological problems, leading to potential discrimination toward these individuals. The internalization of these negative beliefs results in self-stigma, leading to reduced self-esteem and motivation to seek help. Even if soldiers form an intention to seek help for their psychological difficulty, barriers to mental health care may prevent the soldier from receiving the help they need. An overall model is proposed to illustrate how the stigma associated with psychological problems can prevent soldiers getting needed help for psychological difficulties and proposed interventions for reducing stigma in a civilian context are considered for military personnel.

Social and emotional difficulties in children with ADHD and the impact on school attendance and healthcare utilization

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Classi Peter

2012-10-01

Full Text Available Abstract Background The objective of this study was to examine the impact of co-occurring social and emotional difficulties on missed school days and healthcare utilization among children with attention deficit/hyperactivity disorder (ADHD. Methods Data were from the 2007 U.S. National Health Interview Survey (NHIS and were based on parental proxy responses to questions in the Sample Child Core, which includes questions on demographics, health, healthcare treatment, and social and emotional status as measured by questions about depression, anxiety, and phobias, as well as items from the brief version of the Strength and Difficulties Questionnaire (SDQ. Logistic regression was used to assess the association between co-occurring social and emotional difficulties with missed school days and healthcare utilization, adjusting for demographics. Results Of the 5896 children aged 6–17 years in the 2007 NHIS, 432 (7.3% had ADHD, based on parental report. Children with ADHD and comorbid depression, anxiety, or phobias had significantly greater odds of experiencing > 2 weeks of missed school days, ≥ 6 visits to a healthcare provider (HCP, and ≥ 2 visits to the ER, compared with ADHD children without those comorbidities (OR range: 2.1 to 10.4. Significantly greater odds of missed school days, HCP visits, and ER visits were also experienced by children with ADHD who were worried, unhappy/depressed, or having emotional difficulties as assessed by the SDQ, compared with ADHD children without those difficulties (OR range: 2.2 to 4.4. Conclusions In children with ADHD, the presence of social and emotional problems resulted in greater odds of missed school days and healthcare utilization. These findings should be viewed in light of the limited nature of the parent-report measures used to assess social and emotional problems.

Inverse radiation problem of temperature distribution in one-dimensional isotropically scattering participating slab with variable refractive index

International Nuclear Information System (INIS)

Namjoo, A.; Sarvari, S.M. Hosseini; Behzadmehr, A.; Mansouri, S.H.

2009-01-01

In this paper, an inverse analysis is performed for estimation of source term distribution from the measured exit radiation intensities at the boundary surfaces in a one-dimensional absorbing, emitting and isotropically scattering medium between two parallel plates with variable refractive index. The variation of refractive index is assumed to be linear. The radiative transfer equation is solved by the constant quadrature discrete ordinate method. The inverse problem is formulated as an optimization problem for minimizing an objective function which is expressed as the sum of square deviations between measured and estimated exit radiation intensities at boundary surfaces. The conjugate gradient method is used to solve the inverse problem through an iterative procedure. The effects of various variables on source estimation are investigated such as type of source function, errors in the measured data and system parameters, gradient of refractive index across the medium, optical thickness, single scattering albedo and boundary emissivities. The results show that in the case of noisy input data, variation of system parameters may affect the inverse solution, especially at high error values in the measured data. The error in measured data plays more important role than the error in radiative system parameters except the refractive index distribution; however the accuracy of source estimation is very sensitive toward error in refractive index distribution. Therefore, refractive index distribution and measured exit intensities should be measured accurately with a limited error bound, in order to have an accurate estimation of source term in a graded index medium.

Do dyslexics have auditory input processing difficulties?

DEFF Research Database (Denmark)

Poulsen, Mads

2011-01-01

Word production difficulties are well documented in dyslexia, whereas the results are mixed for receptive phonological processing. This asymmetry raises the possibility that the core phonological deficit of dyslexia is restricted to output processing stages. The present study investigated whether....... The finding suggests that input processing difficulties are associated with the phonological deficit, but that these difficulties may be stronger above the level of phoneme perception.......Word production difficulties are well documented in dyslexia, whereas the results are mixed for receptive phonological processing. This asymmetry raises the possibility that the core phonological deficit of dyslexia is restricted to output processing stages. The present study investigated whether...... a group of dyslexics had word level receptive difficulties using an auditory lexical decision task with long words and nonsense words. The dyslexics were slower and less accurate than chronological age controls in an auditory lexical decision task, with disproportionate low performance on nonsense words...

Normative Data of the Self-Report Version of the German Strengths and Difficulties Questionnaire in an Epidemiological Setting.

Science.gov (United States)

Becker, Andreas; Wang, Biyao; Kunze, Barbara; Otto, Christiane; Schlack, Robert; Hölling, Heike; Ravens-Sieberer, Ulrike; Klasen, Fionna; Rogge, Jana; Isensee, Corinna; Rothenberger, Aribert; Bella Study Group, The

2018-05-30

This study served to establish German norms for the Strengths and Difficulties Questionnaire self-report (SDQ-S) by using data from a representative epidemiological sample from the German National Health Interview and Examination Survey for Children and Adolescents (KiGGS study). Although the German version of the SDQ has been widely used and normative data for the parent version (SDQ-P) exist, no German norms for the self-report version have been reported, so that practitioners had to rely on the available British norms. In addition, we investigated whether sex- and age-specific norms are necessary. At the baseline of the KiGGS study, SDQ-S ratings were collected from n = 6,726 children and adolescents between 11 and 17 years (n = 3,440 boys und n = 3,286 girls). We assessed the internal consistency and age/sex effects of the SDQ-S. Confirmatory factor analysis was conducted to assess the factor structure of the SDQ-S. Banding scores were developed to differentiate children and adolescents with levels of difficulties and categorized them as "normal," "borderline," and "abnormal." General as well as age- and sex-specific bandings were created for both total score and subscales of SDQ-S. In addition, the German norms of the SDQ-S were compared with those of the UK, Norway, and Thailand. The five-factor solution of the SDQ-S (including Emotional symptoms, Conduct problems, Hyperactivity/Inattention, Peer problems, and Prosocial behavior) provided a satisfactory fit to the data. Moderate internal consistencies (Cronbach's α) were observed for the scales Emotional symptoms, Hyperactivity/Inattention, and Total difficulties score, whereas insufficient internal consistency was found for the scales Peer problems and Conduct problems. However, using McDonald's ω as a more appropriate measure of homogeneity, internal consistencies were found to be satisfactory for all subscales and for Total difficulties. Normative banding scores were established conservatively to avoid

Dorso-Lateral Frontal Cortex of the Ferret Encodes Perceptual Difficulty during Visual Discrimination

OpenAIRE

Zhe Charles Zhou; Chunxiu Yu; Kristin K. Sellers; Flavio Fröhlich

2016-01-01

Visual discrimination requires sensory processing followed by a perceptual decision. Despite a growing understanding of visual areas in this behavior, it is unclear what role top-down signals from prefrontal cortex play, in particular as a function of perceptual difficulty. To address this gap, we investigated how neurons in dorso-lateral frontal cortex (dl-FC) of freely-moving ferrets encode task variables in a two-alternative forced choice visual discrimination task with high- and low-contr...

Framework for understanding the patterns of student difficulties in quantum mechanics

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Emily Marshman

2015-09-01

Full Text Available [This paper is part of the Focused Collection on Upper Division Physics Courses.] Compared with introductory physics, relatively little is known about the development of expertise in advanced physics courses, especially in the case of quantum mechanics. Here, we describe a framework for understanding the patterns of student reasoning difficulties and how students develop expertise in quantum mechanics. The framework posits that the challenges many students face in developing expertise in quantum mechanics are analogous to the challenges introductory students face in developing expertise in introductory classical mechanics. This framework incorporates both the effects of diversity in upper-level students’ prior preparation, goals, and motivation in general (i.e., the facts that even in upper-level courses, students may be inadequately prepared, have unclear goals, and have insufficient motivation to excel as well as the “paradigm shift” from classical mechanics to quantum mechanics. The framework is based on empirical investigations demonstrating that the patterns of reasoning, problem-solving, and self-monitoring difficulties in quantum mechanics bear a striking resemblance to those found in introductory classical mechanics. Examples from research in quantum mechanics and introductory classical mechanics are discussed to illustrate how the patterns of difficulties are analogous as students learn to unpack the respective principles and grasp the formalism in each knowledge domain during the development of expertise. Embracing such a framework and contemplating the parallels between the difficulties in these two knowledge domains can enable researchers to leverage the extensive literature for introductory physics education research to guide the design of teaching and learning tools for helping students develop expertise in quantum mechanics.

Framework for understanding the patterns of student difficulties in quantum mechanics

Science.gov (United States)

Marshman, Emily; Singh, Chandralekha

2015-12-01

[This paper is part of the Focused Collection on Upper Division Physics Courses.] Compared with introductory physics, relatively little is known about the development of expertise in advanced physics courses, especially in the case of quantum mechanics. Here, we describe a framework for understanding the patterns of student reasoning difficulties and how students develop expertise in quantum mechanics. The framework posits that the challenges many students face in developing expertise in quantum mechanics are analogous to the challenges introductory students face in developing expertise in introductory classical mechanics. This framework incorporates both the effects of diversity in upper-level students' prior preparation, goals, and motivation in general (i.e., the facts that even in upper-level courses, students may be inadequately prepared, have unclear goals, and have insufficient motivation to excel) as well as the "paradigm shift" from classical mechanics to quantum mechanics. The framework is based on empirical investigations demonstrating that the patterns of reasoning, problem-solving, and self-monitoring difficulties in quantum mechanics bear a striking resemblance to those found in introductory classical mechanics. Examples from research in quantum mechanics and introductory classical mechanics are discussed to illustrate how the patterns of difficulties are analogous as students learn to unpack the respective principles and grasp the formalism in each knowledge domain during the development of expertise. Embracing such a framework and contemplating the parallels between the difficulties in these two knowledge domains can enable researchers to leverage the extensive literature for introductory physics education research to guide the design of teaching and learning tools for helping students develop expertise in quantum mechanics.

Variability in emotional/behavioral problems in boys with oppositional defiant disorder or conduct disorder: the role of arousal.

Science.gov (United States)

Schoorl, Jantiene; Van Rijn, Sophie; De Wied, Minet; Van Goozen, Stephanie H M; Swaab, Hanna

2016-08-01

It is often reported that children with oppositional defiant disorder (ODD) or conduct disorder (CD) are under-aroused. However, the evidence is mixed, with some children with ODD/CD displaying high arousal. This has led to the hypothesis that different profiles of arousal dysfunction may exist within children with ODD/CD. This knowledge could explain variability within children with ODD/CD, both in terms of specific types of aggression as well as comorbid symptoms (e.g., other emotional/behavioral problems). We measured heart rate variability (HRV), heart rate (HR) and skin conductance level (SCL) during rest and stress, and obtained parent and teacher reports of aggression, anxiety, attention problems and autism traits in a sample of 66 ODD/CD and 36 non-clinical boys (aged 8-12 years). The ODD/CD group scored significantly higher on aggression, anxiety, attention problems and autism traits than the controls; boys with ODD/CD also had higher resting HRs than controls, but HR stress, HRV and SCL did not differ. Hierarchical regressions showed different physiological profiles in subgroups of boys with ODD/CD based on their type of aggression; a pattern of high baseline HR and SCL, but low stress HRV was related to reactive aggression, whereas the opposite physiological pattern (low HR, low stress SCL, high stress HRV) was related to proactive aggression. Furthermore, high stress SCL was related to anxiety symptoms, whereas low stress SCL was related to attention problems. These findings are important because they indicate heterogeneity within boys with ODD/CD and highlight the importance of using physiology to differentiate boys with different ODD/CD subtypes.

Representing general theoretical concepts in structural equation models: The role of composite variables

Science.gov (United States)

Grace, J.B.; Bollen, K.A.

2008-01-01

Structural equation modeling (SEM) holds the promise of providing natural scientists the capacity to evaluate complex multivariate hypotheses about ecological systems. Building on its predecessors, path analysis and factor analysis, SEM allows for the incorporation of both observed and unobserved (latent) variables into theoretically-based probabilistic models. In this paper we discuss the interface between theory and data in SEM and the use of an additional variable type, the composite. In simple terms, composite variables specify the influences of collections of other variables and can be helpful in modeling heterogeneous concepts of the sort commonly of interest to ecologists. While long recognized as a potentially important element of SEM, composite variables have received very limited use, in part because of a lack of theoretical consideration, but also because of difficulties that arise in parameter estimation when using conventional solution procedures. In this paper we present a framework for discussing composites and demonstrate how the use of partially-reduced-form models can help to overcome some of the parameter estimation and evaluation problems associated with models containing composites. Diagnostic procedures for evaluating the most appropriate and effective use of composites are illustrated with an example from the ecological literature. It is argued that an ability to incorporate composite variables into structural equation models may be particularly valuable in the study of natural systems, where concepts are frequently multifaceted and the influence of suites of variables are often of interest. ?? Springer Science+Business Media, LLC 2007.

Glogs as Non-Routine Problem Solving Tools in Mathematics

Science.gov (United States)

Devine, Matthew T.

2013-01-01

In mathematical problem solving, American students are falling behind their global peers because of a lack of foundational and reasoning skills. A specific area of difficulty with problem solving is working non-routine, heuristic-based problems. Many students are not provided with effective instruction and often grow frustrated and dislike math.…

Eye-Tracking Study of Complexity in Gas Law Problems

Science.gov (United States)

Tang, Hui; Pienta, Norbert

2012-01-01

This study, part of a series investigating students' use of online tools to assess problem solving, uses eye-tracking hardware and software to explore the effect of problem difficulty and cognitive processes when students solve gas law word problems. Eye movements are indices of cognition; eye-tracking data typically include the location,…

Some difficulties and inconsistencies when using habit strength and reasoned action variables in models of metered household water conservation.

Science.gov (United States)

Jorgensen, Bradley S; Martin, John F; Pearce, Meryl; Willis, Eileen

2013-01-30

Research employing household water consumption data has sought to test models of water demand and conservation using variables from attitude theory. A significant, albeit unrecognised, challenge has been that attitude models describe individual-level motivations while consumption data is recorded at the household level thereby creating inconsistency between units of theory and measurement. This study employs structural equation modelling and moderated regression techniques to addresses the level of analysis problem, and tests hypotheses by isolating effects on water conservation in single-person households. Furthermore, the results question the explanatory utility of habit strength, perceived behavioural control, and intentions for understanding metered water conservation in single-person households. For example, evidence that intentions predict water conservation or that they interact with habit strength in single-person households was contrary to theoretical expectations. On the other hand, habit strength, self-reports of past water conservation, and perceived behavioural control were good predictors of intentions to conserve water. Copyright © 2012 Elsevier Ltd. All rights reserved.

Estrés laboral en profesores de enseñanza secundaria: examinando el papel de las conductas y/o actitudes problemáticas de los alumnos y la dificultad percibida en el manejo de conflictos. Occupational stress in secondary school teachers: examining the role of students’ disruptive behaviour and/or attitudes and the perceived difficulty in conflict management

Directory of Open Access Journals (Sweden)

María J. Santiago

2008-03-01

Full Text Available

En este trabajo se examina, en función de distintas variables sociodemográficas y ocupacionales (sexo, edad, experiencia profesional, ciclo de docencia, no sólo el papel de las conductas y/o actitudes problemáticas de los alumnos, sino también las dificultades percibidas por los profesores en el manejo de conflictos. Los resultados obtenidos, a partir de una muestra de 1.386 docentes de ESO, permiten concluir que ambos tipos de estresores diferencian válidamente en función de las variables sociodemográficas y ocupacionales. Concretamente, el estrés asociado a los problemas de comportamiento de los alumnos y a las dificultades del docente en el manejo de conflictos, incide en mayor medida en las profesoras, en los docentes de segundo ciclo y en aquellas etapas intermedias de la profesión. En definitiva, si estos hallazgos se ratifican en futuras investigaciones, se trataría de diseñar programas preventivos y/o de intervención que sean sensibles a estos factores de riesgo.

Palabras clave: Estrés, profesores, conductas problema alumnos, manejo conflictos.

This study examines not only the role of students’ disruptive behaviour and/or attitudes but also the difficulties perceived by teachers in managing conflicts as a function of the different sociodemographic and occupational variables (gender, age, professional experience, teaching cycle. The results obtained from a sample consisting in 1386 ESO teachers allow us to conclude that both types of stressors validly discriminate as a function of sociodemographic and occupational variables. Specifically, the stress associated to students’ disruptive behaviour and to the difficulties faced by teachers in managing conflict has a greater incidence on female teachers, on second cycle teachers and on intermediate stages in the profession. If these findings are corroborated by further research, it would be important to design prevention and/or intervention programmes that are

Where is the problem?

International Nuclear Information System (INIS)

Levy-Leblond, J.-M.

1990-01-01

This paper examines the problem of the reduction of the state vector in quantum theory. The author suggest that this issue ceases to cause difficulties if viewed from the correct perspective, for example by giving the state vector an auxiliary rather than fundamental status. He advocates changing the conceptual framework of quantum theory and working with quantons rather than particles and/or waves. He denies that reduction is a psychophysiological problem of observation, and raises the relevance of experimental apparatus. He concludes by venturing the suggestion that the problem of the reduction of the quantum state vector lies, not in quantum theory, but in classical perspectives. (UK)

Difficulty Identifying Feelings, Distress Tolerance and Compulsive Buying: Analyzing the Associations to Inform Therapeutic Strategies

Science.gov (United States)

Rose, Paul; Segrist, Daniel J.

2012-01-01

Difficulty identifying feelings (a component of alexithymia) and distress tolerance both appear to play a role in impulse-control problems. The goal of the present study was to build upon past research by developing a model of the relations between these constructs and compulsive buying. Participants from the United States and Canada completed a…

Soil physics and the water management of spatially variable soils

International Nuclear Information System (INIS)

Youngs, E.G.

1983-01-01

The physics of macroscopic soil-water behaviour in inert porous materials has been developed by considering water flow to take place in a continuum. This requires the flow region to consist of an assembly of representative elementary volumes, repeated throughout space and small compared with the scale of observations. Soil-water behaviour in swelling soils may also be considered as a continuum phenomenon so long as the soil is saturated and swells and shrinks in the normal range. Macroscale heterogeneity superimposed on the inherent microscale heterogeneity can take many forms and may pose difficulties in the definition and measurement of soil physical properties and also in the development and use of predictive theories of soil-water behaviour. Thus, measurement techniques appropriate for uniform soils are often inappropriate, and criteria for soil-water management, obtained from theoretical considerations of behaviour in equivalent uniform soils, are not applicable without modification when there is soil heterogeneity. The spatial variability of soil-water properties is shown in results from field experiments concerned with water flow measurements; these illustrate both stochastic and deterministic heterogeneity in soil-water properties. Problems of water management of spatially variable soils when there is stochastic heterogeneity appear to present an insuperable problem in the application of theory. However, for soils showing deterministic heterogeneity, soil-water theory has been used in the solution of soil-water management problems. Thus, scaling using similar media theory has been applied to the infiltration of water into soils that vary over a catchment area. Also, the drain spacing to control the water-table height in soils in which the hydraulic conductivity varies with depth has been calculated using groundwater seepage theory. (author)

Variability Bugs:

DEFF Research Database (Denmark)

Melo, Jean

. Although many researchers suggest that preprocessor-based variability amplifies maintenance problems, there is little to no hard evidence on how actually variability affects programs and programmers. Specifically, how does variability affect programmers during maintenance tasks (bug finding in particular......)? How much harder is it to debug a program as variability increases? How do developers debug programs with variability? In what ways does variability affect bugs? In this Ph.D. thesis, I set off to address such issues through different perspectives using empirical research (based on controlled...... experiments) in order to understand quantitatively and qualitatively the impact of variability on programmers at bug finding and on buggy programs. From the program (and bug) perspective, the results show that variability is ubiquitous. There appears to be no specific nature of variability bugs that could...

Medical Students' Perception of Problem Areas in Anatomy ...

African Journals Online (AJOL)

The ranges of problems were extensive; neuro-anatomy in gross anatomy, slide review in histology, and cardiovascular embryology were amongst the most highlighted areas of concern. Most students attributed the problems in gross anatomy to difficulty with accessing the area during dissection and inability to grasp the ...

What Makes a Beam Shaping Problem Difficult

International Nuclear Information System (INIS)

Romero, Louis; Dickey, Fred M.

2000-01-01

The authors have discussed the three factors that they believe are the most important in determining the difficulty of a beam shaping problem: scaling, smoothness, and coherence. The arguments have been almost completely based on considering how these factors influence beam shaping lenses that were designed using geometrical optics. However, they believe that these factors control the difficulty of beam shaping problems even if one does not base ones design strategy on geometrical optics. For example, they have shown that a lens designed using geometrical optics will not work well unless β is large. However, they have also shown that if β is small the uncertainty principle shows that it is impossible to do a good job of beam shaping no matter how one designs ones lens

Difficulties in social functioning of adolescents with different family and intellectual status

Directory of Open Access Journals (Sweden)

Jelić Marija M.

2016-01-01

Full Text Available Bearing in mind limited effects of interventions focused on the child and its limitations the attention of researches is more and more directed to immediate and wider ambience factors in the prevention of negative forms of behaviour of children. The aim of the research was to determine the level of connectedness of family and intellectual status of adolescents and different aspects of their social functioning. The sample of 416 adolescents, aged 12 to 18, was divided into two groups. The group without parental care included 210 respondents (130 with typical development - TD and 80 with mild intellectual disability - MID, and the group with parental care (130 TD and 76 MID. We used Strengths and Difficulties Questionnaire with subscales: behavioral problems, emotional problems and problems with peers. Family problems were divided in socioeconomic problems, partners' problem, mental health of parents, abuse, and neglect. The results confirmed that the young without parental care showed more problems in behavior than their peers with parental care, and that family status affects behavior more than intellectual status. Family is the protective factor for the development of emotional problems of the young TD students, while it is risky for MID students. Problems with peers are not significantly connected with family or intellectual status. Some implications of the results are stressed.

Function theory of several complex variables

CERN Document Server

Krantz, Steven G

2001-01-01

The theory of several complex variables can be studied from several different perspectives. In this book, Steven Krantz approaches the subject from the point of view of a classical analyst, emphasizing its function-theoretic aspects. He has taken particular care to write the book with the student in mind, with uniformly extensive and helpful explanations, numerous examples, and plentiful exercises of varying difficulty. In the spirit of a student-oriented text, Krantz begins with an introduction to the subject, including an insightful comparison of analysis of several complex variables with th

Attention problems in childhood and adult substance use.

Science.gov (United States)

Galéra, Cédric; Pingault, Jean-Baptiste; Fombonne, Eric; Michel, Grégory; Lagarde, Emmanuel; Bouvard, Manuel-Pierre; Melchior, Maria

2013-12-01

To assess the link between childhood attention problems (AP) and substance use 18 years later. This cohort study was conducted in a community sample of 1103 French youths followed from 1991 to 2009. Exposures and covariates were childhood behavioral problems (based on parental report at baseline), early substance use, school difficulties, and family adversity. Outcome measures were regular tobacco smoking, alcohol problems, problematic cannabis use, and lifetime cocaine use (based on youth reports at follow-up). Individuals with high levels of childhood AP had higher rates of substance use (regular tobacco smoking, alcohol problems, problematic cannabis use, and lifetime cocaine use). However, when taking into account other childhood behavioral problems, early substance use, school difficulties, and family adversity, childhood AP were related only to regular tobacco smoking and lifetime cocaine use. Early cannabis exposure was the strongest risk factor for all substance use problems. This longitudinal community-based study shows that, except for tobacco and cocaine, the association between childhood AP and substance use is confounded by a range of early risk factors. Early cannabis exposure plays a central role in later substance use. Copyright © 2013 Mosby, Inc. All rights reserved.

K-State Problem Identification Rating Scales for College Students

Science.gov (United States)

Robertson, John M.; Benton, Stephen L.; Newton, Fred B.; Downey, Ronald G.; Marsh, Patricia A.; Benton, Sheryl A.; Tseng, Wen-Chih; Shin, Kang-Hyun

2006-01-01

The K-State Problem Identification Rating Scales, a new screening instrument for college counseling centers, gathers information about clients' presenting symptoms, functioning levels, and readiness to change. Three studies revealed 7 scales: Mood Difficulties, Learning Problems, Food Concerns, Interpersonal Conflicts, Career Uncertainties,…

Integer programming formulation and variable neighborhood search metaheuristic for the multiproduct pipeline scheduling problem

Energy Technology Data Exchange (ETDEWEB)

Souza Filho, Erito M.; Bahiense, Laura; Ferreira Filho, Virgilio J.M. [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia (COPPE); Lima, Leonardo [Centro Federal de Educacao Tecnologica Celso Sukow da Fonseca (CEFET-RJ), Rio de Janeiro, RJ (Brazil)

2008-07-01

Pipeline are known as the most reliable and economical mode of transportation for petroleum and its derivatives, especially when large amounts of products have to be pumped for large distances. In this work we address the short-term schedule of a pipeline system comprising the distribution of several petroleum derivatives from a single oil refinery to several depots, connected to local consumer markets, through a single multi-product pipeline. We propose an integer linear programming formulation and a variable neighborhood search meta-heuristic in order to compare the performances of the exact and heuristic approaches to the problem. Computational tests in C language and MOSEL/XPRESS-MP language are performed over a real Brazilian pipeline system. (author)

Amplification factor variable amplifier

NARCIS (Netherlands)

Akitsugu, Oshita; Nauta, Bram

2007-01-01

PROBLEM TO BE SOLVED: To provide an amplification factor variable amplifier capable of achieving temperature compensation of an amplification factor over a wide variable amplification factor range. ; SOLUTION: A Gilbert type amplification factor variable amplifier 11 amplifies an input signal and

Source localization in electromyography using the inverse potential problem

Science.gov (United States)

van den Doel, Kees; Ascher, Uri M.; Pai, Dinesh K.

2011-02-01

We describe an efficient method for reconstructing the activity in human muscles from an array of voltage sensors on the skin surface. MRI is used to obtain morphometric data which are segmented into muscle tissue, fat, bone and skin, from which a finite element model for volume conduction is constructed. The inverse problem of finding the current sources in the muscles is solved using a careful regularization technique which adds a priori information, yielding physically reasonable solutions from among those that satisfy the basic potential problem. Several regularization functionals are considered and numerical experiments on a 2D test model are performed to determine which performs best. The resulting scheme leads to numerical difficulties when applied to large-scale 3D problems. We clarify the nature of these difficulties and provide a method to overcome them, which is shown to perform well in the large-scale problem setting.

Source localization in electromyography using the inverse potential problem

International Nuclear Information System (INIS)

Van den Doel, Kees; Ascher, Uri M; Pai, Dinesh K

2011-01-01

We describe an efficient method for reconstructing the activity in human muscles from an array of voltage sensors on the skin surface. MRI is used to obtain morphometric data which are segmented into muscle tissue, fat, bone and skin, from which a finite element model for volume conduction is constructed. The inverse problem of finding the current sources in the muscles is solved using a careful regularization technique which adds a priori information, yielding physically reasonable solutions from among those that satisfy the basic potential problem. Several regularization functionals are considered and numerical experiments on a 2D test model are performed to determine which performs best. The resulting scheme leads to numerical difficulties when applied to large-scale 3D problems. We clarify the nature of these difficulties and provide a method to overcome them, which is shown to perform well in the large-scale problem setting

Ultrahigh-dimensional variable selection method for whole-genome gene-gene interaction analysis

Directory of Open Access Journals (Sweden)

Ueki Masao

2012-05-01

Full Text Available Abstract Background Genome-wide gene-gene interaction analysis using single nucleotide polymorphisms (SNPs is an attractive way for identification of genetic components that confers susceptibility of human complex diseases. Individual hypothesis testing for SNP-SNP pairs as in common genome-wide association study (GWAS however involves difficulty in setting overall p-value due to complicated correlation structure, namely, the multiple testing problem that causes unacceptable false negative results. A large number of SNP-SNP pairs than sample size, so-called the large p small n problem, precludes simultaneous analysis using multiple regression. The method that overcomes above issues is thus needed. Results We adopt an up-to-date method for ultrahigh-dimensional variable selection termed the sure independence screening (SIS for appropriate handling of numerous number of SNP-SNP interactions by including them as predictor variables in logistic regression. We propose ranking strategy using promising dummy coding methods and following variable selection procedure in the SIS method suitably modified for gene-gene interaction analysis. We also implemented the procedures in a software program, EPISIS, using the cost-effective GPGPU (General-purpose computing on graphics processing units technology. EPISIS can complete exhaustive search for SNP-SNP interactions in standard GWAS dataset within several hours. The proposed method works successfully in simulation experiments and in application to real WTCCC (Wellcome Trust Case–control Consortium data. Conclusions Based on the machine-learning principle, the proposed method gives powerful and flexible genome-wide search for various patterns of gene-gene interaction.

Temperament and character effects on late adolescents’ well-being and emotional-behavioural difficulties

Directory of Open Access Journals (Sweden)

Cristiano Crescentini

2018-03-01

Full Text Available Background Research on adults points to personality as a crucial determinant of well-being. The present study investigates the question of personality’s relation to well-being and psychosocial adjustment in adolescence. Methods We assessed the role of temperament and character (Temperament and Character Inventory, TCI-125, on psychological well-being (PWB; Psychological Well-Being scales, subjective well-being (SWB; Positive and Negative Affect, PA and NA, respectively, and psychosocial adjustment (emotional-behavioural problems measured by the Strengths and Difficulties Questionnaire for Adolescents, SDQ-A, in 72 Italian late adolescents (aged 17.5 ± 0.75. Multiple regressions were conducted to predict PWB, SWB, and SDQ-A scores using TCI-125 scales as predictors. Results Character maturity, and in particular Self-Directedness, had a widespread protective effect on well-being and psychosocial adjustment, while different strengths and emotional-behavioural difficulties were associated to specific temperamental and character traits. For example, Harm-Avoidance and Novelty-Seeking positively predicted internalized and externalized problems, respectively. Discussion The present results suggest the usefulness of continuing to evaluate temperament and, in particular, character dimensions in investigations focused on adolescents’ well-being and psychosocial functioning, especially in the contexts of potential interventions aimed at enhancing development of adolescents’ character dimensions at the intrapersonal, interpersonal, and transpersonal levels.

Temperament and character effects on late adolescents' well-being and emotional-behavioural difficulties.

Science.gov (United States)

Crescentini, Cristiano; Garzitto, Marco; Paschetto, Andrea; Brambilla, Paolo; Fabbro, Franco

2018-01-01

Research on adults points to personality as a crucial determinant of well-being. The present study investigates the question of personality's relation to well-being and psychosocial adjustment in adolescence. We assessed the role of temperament and character (Temperament and Character Inventory, TCI-125), on psychological well-being (PWB; Psychological Well-Being scales), subjective well-being (SWB; Positive and Negative Affect, PA and NA, respectively), and psychosocial adjustment (emotional-behavioural problems measured by the Strengths and Difficulties Questionnaire for Adolescents, SDQ-A), in 72 Italian late adolescents (aged 17.5 ± 0.75). Multiple regressions were conducted to predict PWB, SWB, and SDQ-A scores using TCI-125 scales as predictors. Character maturity, and in particular Self-Directedness, had a widespread protective effect on well-being and psychosocial adjustment, while different strengths and emotional-behavioural difficulties were associated to specific temperamental and character traits. For example, Harm-Avoidance and Novelty-Seeking positively predicted internalized and externalized problems, respectively. The present results suggest the usefulness of continuing to evaluate temperament and, in particular, character dimensions in investigations focused on adolescents' well-being and psychosocial functioning, especially in the contexts of potential interventions aimed at enhancing development of adolescents' character dimensions at the intrapersonal, interpersonal, and transpersonal levels.

Diversity of problems of international mathematical olympiads (imo)

OpenAIRE

Kukuraitis, Nerijus

2012-01-01

Šiame darbe yra pateikta 16 Pasaulinių olimpiadų uždavinių ir jų sprendimų. Uždaviniai yra lyginami pagal jų sudėtingumo lygį. Sixteen problems and their solutions from International Mathematical Olympiads are presented in this work. Problems are compared by their difficulty.

Children with Autism: Sleep Problems and Mothers' Stress

Science.gov (United States)

Hoffman, Charles D.; Sweeney, Dwight P.; Lopez-Wagner, Muriel C.; Hodge, Danelle; Nam, Cindy Y.; Botts, Betsy H.

2008-01-01

Parenting a child with autism has been associated with maternal stress. The present investigation examined children's sleep difficulties and severity of autism along with mothers' sleep problems in relation to stress levels reported by mothers ( N = 72). Mothers' reports of their children's sleep problems were related to mothers' reports of their…

Human factors implications of unmanned aircraft accidents : flight-control problems

Science.gov (United States)

2006-04-01

This research focuses on three types of flight control problems associated with unmanned aircraft systems. The : three flight control problems are: 1) external pilot difficulties with inconsistent mapping of the controls to the : movement of the airc...

Desirable difficulties in vocabulary learning

OpenAIRE

Bjork, RA; Kroll, JF

2015-01-01

© 2015 by the Board of Trustees of the University of Illinois. In this article we discuss the role of desirable difficulties in vocabulary learning from two perspectives, one having to do with identifying conditions of learning that impose initial challenges to the learner but then benefit later retention and transfer, and the other having to do with the role of certain difficulties that are intrinsic to language processes, are engaged during word learning, and reflect how language is underst...

The Use of Open-Ended Problem-Based Learning Scenarios in an Interdisciplinary Biotechnology Class: Evaluation of a Problem-Based Learning Course Across Three Years

Directory of Open Access Journals (Sweden)

Todd R. Steck

2012-02-01

Full Text Available Use of open-ended Problem-Based Learning (PBL in biology classrooms has been limited by the difficulty in designing problem scenarios such that the content learned in a course can be predicted and controlled, the lack of familiarity of this method of instruction by faculty, and the difficulty in assessment. Here we present the results of a study in which we developed a team-based interdisciplinary course that combined the fields of biology and civil engineering across three years. We used PBL scenarios as the only learning tool, wrote the problem scenarios, and developed the means to assess these courses and the results of that assessment. Our data indicates that PBL changed students’ perception of their learning in content knowledge and promoted a change in students’ learning styles. Although no  statistically significant improvement in problem-solving skills and critical thinking skills was observed, students reported substantial changes in their problem-based learning strategies and critical thinking skills.

Problem-oriented approach to Ancient philosophy

Directory of Open Access Journals (Sweden)

Berstov, Igor

2007-06-01

Full Text Available Igor Berestov and Marina Wolf of the Institute of philosophy and law, Novosibirsk, discuss various methodological difficulties typical of studies in the history of Ancient Greek philosophy and try to develop their own problem-oriented approach.

Amplification factor variable amplifier

NARCIS (Netherlands)

Akitsugu, Oshita; Nauta, Bram

2010-01-01

PROBLEM TO BE SOLVED: To provide an amplification factor variable amplifier capable of achieving temperature compensation of an amplification factor over a wide variable amplification factor range. ;SOLUTION: A Gilbert type amplification factor variable amplifier 11 amplifies an input signal and can

Modelling Question Difficulty in an A Level Physics Examination