Delta modulation of time-discrete signals with independent samples

Previous studies of Delta Modulation (DM) were predominantly concerned with various aspects of noise introduced by the quantising process. This paper is primarily directed towards the DM-signal behaviour, a concern which becomes necessary when optimizing the DM-system against the disturbances of the transmission channel. The statistics of the output signal is considered analytically under the assumption of independent input-signal samples. The approximate distribution of the output signal is derived and graphically compared with the exact distribution. Finally, the incidence of sample correlation is considered on the basis of results produced by means of simulation.     

Process over product: the next evolution of our quest for technology integration

Educational technology research and development - The purpose of this paper is to introduce the next evolution of our quest for technology integration, one that moves away from the product of...     

Relaxation and guided imagery as an intervention for children with asthma: A replication

Asthma is a pervasive inflammatory disorder of the bronchial airways that causes the normal functioning of the airways to become overreactive. This disorder affects approximately 8 million children in schools per year and accounts for a significant amount of absences. Researchers have speculated that pharmacological interventions are alone insufficient or overaggressive in treating asthma, and numerous studies have demonstrated a connection between emotions and asthma. It has therefore been suggested that psychological interventions may be appropriate for this population. One such intervention, relaxation and guided imagery (RGI), that incorporates mental representations as well as the senses in a process of relaxing all the parts of the body has been shown to be effective with children with asthma. The current study served as a replication and extension of this previous research. The purpose of the investigation was to examine the effectiveness of RGI with an elementary school sample as well as determine the overall improvement in happiness, anxiety, and quality of life of the participants. Results demonstrated that RGI significantly improved the lung functioning of 3 out of 4 participants in the study. Furthermore, overall happiness improved for 1 participant in the study, state anxiety decreased for 2 of the 4 participants, and trait anxiety decreased for all 4 participants. © 2005 Wiley Periodicals, Inc. Psychol Schs 42: 707–720, 2005.     

An examination of alternate assessment durations when assessing multiple‐skill computational fluency: The generalizability and dependability of curriculum‐based outcomes within the context of educational decisions

The current study extended previous research on curriculum‐based measurement in mathematics (M‐CBM) assessments. The purpose was to examine the generalizability and dependability of multiple‐skill M‐CBM computation assessments across various assessment durations (1, 2, 3, 4, 5, and 6 minutes). Results of generalizability and dependability studies (N = 104 students) suggest that relative interindividual decisions can rely on the results from 1‐minute administrations for low‐stakes decisions and the results of 4‐minute administrations for high‐stakes decisions. Moreover, absolute intraindividual decisions can rely on the results from 4‐minute administrations for low‐stakes decisions and 13‐minute administrations for high‐stakes decisions. The implications and limitations of these results are discussed. © 2005 Wiley Periodicals, Inc. Psychol Schs 42: 615–622, 2005.     

Towards a Liberal Vocational Education

This essay takes up the issue of the impact of technology on jobs in modern workplaces, and the curricular challenges thereby engendered for vocational educators. Conceptions of the nature of workplaces are examined, along with conceptions of the types of skill needed. It is proposed that distinction be made between vocational education at the secondary school, and that beyond. At the secondary school, vocational education would be education about work , and the goal would be vocational literacy. This would constitute a liberal vocational education. Beyond that, vocational education would be for jobs , but would include liberal features, such as general education course work, and training in job families.     

Rhetoric Versus Reality in Educational Reform: The Case of the National Science Foundation's Urban Systemic Initiative

In this paper, we present findings from a study assessing the impact of reforms on mathematics and science instruction to illustrate the multiple levels at which educational change must occur to promote student achievement and close achievement gaps. We undertake an analysis of the extent to which the rhetoric of national policy, in this case, the National Science Foundation's Urban Systemic Initiative, matches the realities of the day-to-day classroom practices we evaluated in our study. Addressed here is the problem of how applied anthropologists can broaden the scope of research and research findings from the edges of the societal mainstream to address larger policy issues. More globally, we discuss the influence of contemporary applied anthropologists and their colleagues who study marginalized groups on educational research.     

Major Differences: Variations in Undergraduate and Graduate Student Mental Health and Treatment Utilization Across Academic Disciplines

This article explores variations in mental health and service utilization across academic disciplines using a random sample of undergraduate and graduate students (N = 64,519) at 81 colleges and universities. We report prevalence of depression, anxiety, suicidality, and self-injury, and rates of help-seeking across disciplines, including results from multivariate logistic regressions. We find significant variations: Students in humanities and art and design are significantly more likely to have mental health problems; and for students with apparent mental health problems, treatment rates are lowest among those in business and engineering. Noting these variations could enhance efforts to promote student mental health, particularly within academic departments.     

Balance in Positive Emotional Expressivity Across School Contexts Relates to Kindergartners’ Adjustment

Positive emotional expressivity has been associated with increased social competence and decreased maladjustment in childhood. However, a few researchers have found null or even positive associations between positive emotional expressivity and maladjustment, which suggests that there may be nuanced associations of positive expressivity, perhaps as a function of the social context in which it is expressed. We examined whether observed positive emotional expressivity balance across peer-oriented/recreational and learning contexts predicted kindergarten children’s adjustment (N = 301). Research Findings: Higher positive expressivity during lunch/recess compared to positive expressivity in the classroom was associated with lower teacher–student conflict, externalizing behaviors, and depressive symptoms. In addition, overall positive emotional expressivity predicted lower externalizing behaviors as well as lower depressive and anxiety symptoms. Practice or Policy: The results suggest the importance of assessing observed positive emotional expressivity in context as a potential indicator of children’s maladjustment risk and the need for children to adapt their emotions to different contexts. Implications for assessing and supporting positive emotional expression balance and training emotional regulation in school are discussed.