319 resultados para Motor behavior


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The main constituents of red mud produced in Aluminio city (S.P. – Brazil) are iron, aluminium and silicon oxides. It has been determined that the average particle diameter for this red mud is between 0.05 and 0.002mm. It is observed that a decrease in the percentage of smaller particles occurs at temperatures greater than 400°C. This observation corresponds with the thermal analysis and X-ray diffraction (XRD) data, which illustrate the phase transition of goethite to hematite. A 10% mass loss is observed in the thermal analysis patterns due to the hydroxide – oxide phase transitions of iron (primary phase transition) and aluminium (to a lesser extent). The disappearance and appearance of the different phases of iron and aluminium confirms the decomposition reactions proposed by the thermal analysis data. This Brazilian red mud has been classified as mesoporous at all temperatures except between 400 and 500°C where the classification changes to micro/mesoporous.

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Purpose: Experimental measurements have been made to investigate meaning of the change in voltage for the pulse gas metal arc welding (GMAW-P) process operating under different drop transfer modes. Design/methodology/approach: Welding experiments with different values of pulsing parameter and simultaneous recording of high speed camera pictures and welding signals (such as current and voltage) were used to identify different drop transfer modes in GMAW-P. The investigation is based on the synchronization of welding signals and high speed camera to study the behaviour of voltage signal under different drop transfer modes. Findings: The results reveal that the welding arc is significantly affected by the molten droplet detachment. In fact, results indicate that sudden increase and drop in voltage just before and after the drop detachment can be used to characterize the voltage behaviour of different drop transfer mode in GMAW-P. Research limitations/implications: The results show that voltage signal carry rich information about different drop transfer occurring in GMAW-P. Hence it’s possible to detect different drop transfer modes. Future work should concentrate on development of filters for detection of different drop transfer modes. Originality/value: Determination of drop transfer mode with GMAW-P is crucial for the appropriate selection of pulse welding parameters. As change in drop transfer mode results in poor weld quality in GMAW-P, so in order to estimate the working parameters and ensure stable GMAW-P understanding the voltage behaviour of different drop transfer modes in GMAW-P will be useful. However, in case of GMAW-P hardly any attempt is made to analyse the behaviour of voltage signal for different drop transfer modes. This paper analyses the voltage signal behaviour of different drop transfer modes for GMAW-P.

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Research Findings: The transition to school is a major developmental milestone, and behavior tendencies already evident at the point of school entry can impact upon a child's subsequent social and academic adjustment. The current study aimed to investigate stability and change in the social behavior of girls and boys across the transition from day care to 1st grade. Teacher ratings and peer nominations for prosocial and antisocial behavior were obtained for 248 children belonging to 2 cohorts: school transitioning (n = 118) and day care remaining (n = 130). Data were gathered again from all children 1 year later, following the older group's entry into school. Teacher ratings of prosocial and antisocial behavior significantly predicted teacher ratings of the same behavior at Time 2 for both cohorts. Peer reports of antisocial behavior also showed significant stability, whereas stability of peer-reported prosocial behavior varied as a function of behavior type. Practice or Policy: The results contribute to understanding of trends in early childhood social behavior that potentially influence long-term developmental trajectories. Identification of some behaviors as more stable in early childhood than others, regardless of school entry, provides useful information for both the type and timing of early interventions. © 2010 Taylor & Francis Group, LLC.

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• What is risk compensation, and why is relevant to motor vehicle crashes? • Recent simulator work that revealed risk compensation • Current and future work on risk compensation

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A service-oriented system is composed of independent software units, namely services, that interact with one another exclusively through message exchanges. The proper functioning of such system depends on whether or not each individual service behaves as the other services expect it to behave. Since services may be developed and operated independently, it is unrealistic to assume that this is always the case. This article addresses the problem of checking and quantifying how much the actual behavior of a service, as recorded in message logs, conforms to the expected behavior as specified in a process model.We consider the case where the expected behavior is defined using the BPEL industry standard (Business Process Execution Language for Web Services). BPEL process definitions are translated into Petri nets and Petri net-based conformance checking techniques are applied to derive two complementary indicators of conformance: fitness and appropriateness. The approach has been implemented in a toolset for business process analysis and mining, namely ProM, and has been tested in an environment comprising multiple Oracle BPEL servers.

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This study describes the treatment of obese individuals who rated high on emotional eating using four case studies that involved 22 sessions of either cognitive behavioral therapy (CBT) or dialectical behavioral therapy (DBT). Outcomes measures relating to weight, body mass index, emotional eating, depression, anxiety, and stress were all assessed with each participant prior to each baseline (three weekly sessions), during treatment and posttherapy. At the 8-week follow-up, the two cases that had received DBT had lost 10.1% and 7.6% of their initial body weight, whereas the two cases that had received CBT had lost 0.7% and 0.6% of their initial body weight. The two DBT cases also exhibited reductions in emotional distress, frequency of emotional eating or quantity of food eating in response to emotions, whereas the two CBT cases showed no overall reductions in these areas. Important processes from all four cases are described as are the implications to clinicians for developing more effective interventions for obese clients who engage in emotional eating.

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Load modelling plays an important role in power system dynamic stability assessment. One of the widely used methods in assessing load model impact on system dynamic response is parametric sensitivity analysis. A composite load model-based load sensitivity analysis framework is proposed. It enables comprehensive investigation into load modelling impacts on system stability considering the dynamic interactions between load and system dynamics. The effect of the location of individual as well as patches of composite loads in the vicinity on the sensitivity of the oscillatory modes is investigated. The impact of load composition on the overall sensitivity of the load is also investigated.

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The method on concurrent multi-scale model of structural behavior (CMSM-of-SB) for the purpose of structural health monitoring including model updating and validating has been studied. The detailed process of model updating and validating is discussed in terms of reduced scale specimen of the steel box girder in longitudinal stiffening truss of a long span bridge. Firstly, some influence factors affecting the accuracy of the CMSM-of-SB including the boundary restraint regidity, the geometry and material parameters on the toe of the weld and its neighbor are analyzed using sensitivity method. Then, sensitivity-based model updating technology is adopted to update the developed CMSM-of-SB and model verification is carried out through calculating and comparing stresses on different locations under various loading from dynamic characteristic and static response. It can be concluded that the CMSM-of-SB based on the substructure method is valid.

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Objectives To evaluate differences among patients with different clinical features of ALS, we used our Bayesian method of motor unit number estimation (MUNE). Methods We performed serial MUNE studies on 42 subjects who fulfilled the diagnostic criteria for ALS during the course of their illness. Subjects were classified into three subgroups according to whether they had typical ALS (with upper and lower motor neurone signs) or had predominantly upper motor neurone weakness with only minor LMN signs, or predominantly lower motor neurone weakness with only minor UMN signs. In all subjects we calculated the half life of MUs, defined as the expected time for the number of MUs to halve, in one or more of the abductor digiti minimi (ADM), abductor pollicis brevis (APB) and extensor digitorum brevis (EDB) muscles. Results The mean half life of MUs was less in subjects who had typical ALS with both upper and lower motor neurone signs than in those with predominantly upper motor neurone weakness or predominantly lower motor neurone weakness. In 18 subjects we analysed the estimated size of the MUs and demonstrated the appearance of large MUs in subjects with upper or lower motor neurone predominant weakness. We found that the appearance of large MUs was correlated with the half life of MUs. Conclusions Patients with different clinical features of ALS have different rates of loss and different sizes of MUs. Significance: These findings could indicate differences in disease pathogenesis.

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The kaolinite intercalation and its application in polymer-based functional composites have attracted great interest, both in industry and in academia fields, since they frequently exhibit remarkable improvements in materials properties compared with the virgin polymer or conventional micro and macro-composites. Also of significant interest regarding the kaolinite intercalation complex is its thermal behavior and decomposition. This is because heating treatment of intercalated kaolinite is necessary for its further application, especially in the field of plastic and rubber industry. Although intercalation of kaolinite is an old and ongoing research topic, there is a limited knowledge available on kaolinite intercalation with different reagents, the mechanism of intercalation complex formation as well as on thermal behavior and phase transition. This review attempts to summarize the most recent achievements in the thermal behavior study of kaolinite intercalation complexes obtained with the most common reagents including potassium acetate, formamide, dimethyl sulfoxide, hydrazine and urea. At the end of this paper, the further work on kaolinite intercalation complex was also proposed.

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Motor vehicle crashes are a leading cause of death among young people. Fourteen percent of adolescents aged 13-14 report passenger-related injuries within three months. Intervention programs typically focus on young drivers and overlook passengers as potential protective influences. Graduated Driver Licensing restricts passenger numbers, and this study focuses on a complementary school-based intervention to increase passengers’ personal- and peer-protective behavior. The aim of this research was to assess the impact of the curriculum-based injury prevention program, Skills for Preventing Injury in Youth (SPIY), on passenger-related risk-taking and injuries, and intentions to intervene in friends’ risky road behavior. SPIY was implemented in Grade 8 Health classes and evaluated using survey and focus group data from 843 students across 10 Australian secondary schools. Intervention students reported less passenger-related risk-taking six months following the program. Their intention to protect friends from underage driving also increased. The results of this study show that a comprehensive, school-based program targeting individual and social changes can increase adolescent passenger safety.

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Aim: To explore the lived experience of post-traumatic stress disorder (PTSD) as described by individuals who have been involved in a motor vehicle accident (MVA) in Jordan. Background: Motor vehicle accident (MVA) survivors who develop post-traumatic stress disorder (PTSD) have become an important health issue. The World Health Organisation (WHO) states that trauma resulting from MVAs is a phenomenon of increasing concern, with death from injuries projected to rise from 5.1 million in 1990 to 8.4 million in 2020 particularly in developing countries such as Jordan (WHO, 2002). The impact of trauma from MVAs inevitably compromises the victim’s quality of life (WHO, 2002; Blanchard & Hickling, 2007) resulting in psychological and emotional distress, occupational disability, family disintegration, and socio-economic difficulty (Jordan Ministry of Health, 2005). The development of PTSD as a result of an MVA is not limited to the individual, but also extends to the family, friends, and the health care team involved in the person's care and rehabilitation. Design: A descriptive phenomenological approach was used for this study. Method: This study was conducted in an orthopaedic unit in Amera Basma Hospital in Irbid Jordan. Fifteen (15) participants were voluntary recruited through the process of purposeful sampling. Data was collected by face-to-face in depth-interviews. Interviews were digitally recorded and transcribed verbatim. The process of analysis was undertaken using Colaizzi’s (1978) eight step approach with the addition of two extra steps. Findings: The process of analysis identified seven themes explicated from the participants’ transcripts of interview. The seven themes were: 1. Feeling frustrated at a diminishing health status 2. Struggling to maintain a sense of independence 3. Harbouring feelings of not being able to recover 4. Feeling discriminated against and marginalised by society 5. Feeling ignored and neglected by health care professionals 6. Feeling abandoned by family, and 7. Moving toward acceptance through having faith in Allah. Conclusion: The findings of this study have the potential to make a significant contribution to extant knowledge on the topic which can inform future nursing practice, education, policy development, and research initiatives in Jordan and internationally.

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This article reviews four bodies of research that shed light on how to promote active care for the environment in children and youth: research on sources of proenvironmental behavior, socialization for democratic skills and values, the development of a personal sense of competence, and the development of collective competence. The article begins with an overview of studies of formative childhood experiences reported by environmental activists and educators, followed by correlational and experimental studies with young people regarding factors associated with their taking action for the environment. Because behaviors with the largest potential benefits for the environment require political engagement, the article also reviews experiences associated with young people’s interest and engagement in public issues. Action for the environment in the home or in public arena like schools and communities requires a personal sense of competence and a sense of collective competence, or confidence in one’s ability to achieve goals by working with a group. Therefore experiences that promote the development of these assets are summarized as well. The conclusion compares major findings in these different fields and discusses implications for environmental educators.

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An extended theory of planned behavior (TPB) was used to predict young people’s intentions to donate money to charities in the future. Students (N = 210; 18-24 years) completed a questionnaire assessing their attitude, subjective norm, perceived behavioral control [PBC], moral obligation, past behavior and intentions toward donating money. Regression analyses revealed the extended TPB explained 61% of the variance in intentions to donate money. Attitude, PBC, moral norm, and past behavior predicted intentions, representing future targets for charitable giving interventions.