The relevance of activity measurement is reviewed. Technical information regarding a new, small, lightweight, fully proportional accelerometer-based activity monitor suited for a wide range of wrist, waist, and ankle activity measurements over extended time periods in free-ranging persons is presented. Calibration data demonstrating within-and between-device reliability and validity are presented. Field trial data are presented showing that wrist and waist actigraphs can predict kilocalories of energy expended. The issue of how activity monitors should be validated is discussed. Instrument reliability is distinguished from clinical repeatability. Recommendations are provided to assist investigators with instrument selection.There are many reasons why a high-quality ambulatory activity monitor is desirable. Activity is a major dimension of infant temperament

High-probability requests were used to increase social interactions in 3 young boys with severe disabilities who had been identified as severely socially withdrawn. A multiple baseline design across participants was used to evaluate the effects of high-probability request intervention on (a) social initiations, (b) social responses, (c) continued interactions, and (d) performance of high- and low-probability requests. The students were observed in a second setting to examine generalization effects across peers who did not participate in the training sequence and settings. The results demonstrated that the high-probability requests increased the students' responsiveness to low-probability requests to initiate social behavior. Increases were also found in (a) unprompted initiations and extended interactions to the training peers, (b) unprompted initiations and extended interactions to peers who were not involved in the training procedure, and (c) generalized unprompted initiations and interactions in a second nontraining setting. The students maintained increased levels of initiations and interactions after all prompts were removed from both the training and nontraining settings.

The failure to respond to requests in young children often is maintained by the reactions of the adults that encounter this behavior. This failure to respond to requests has been identified as a primary reason for the children's exclusion from community, social, and instructional opportunities. Numerous interventions that target the failure to respond have consisted of punishment and reinforcement procedures. More recently, antecedent interventions have focused on changing the context in which a request is delivered. In the current study, high-probability requests were provided as an antecedent to delivering a low-probability request. The requests were delivered by multiple trainers in an attempt to produce generalized appropriate responding to adults who did not use the high-probability sequence. Results showed an immediate increase in appropriate responding in 2 children when the intervention was delivered. In addition, when the intervention was implemented by more than one adult, spontaneous increases in responding also were observed toward adults who had never implemented the request sequence. Improvements in responding to requests were maintained after the intervention was discontinued.

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Hybrid additive manufacturing (hybrid-AM) has described hybrid processes and machines as well as multimaterial, multistructural, and multifunctional printing. The capabilities afforded by hybrid-AM are rewriting the design rules for materials and adding a new dimension in the design for additive manufacturing (AM) paradigm. This work primarily focuses on defining hybrid-AM in relation to hybrid manufacturing (HM) and classifying hybrid-AM processes. Hybrid-AM machines, materials, structures, and function are also discussed. Hybrid-AM processes are defined as the use of AM with one or more secondary processes or energy sources that are fully coupled and synergistically affect part quality, functionality, and/or process performance. Historically, defining HM processes centered on process improvement rather than improvements to part quality or performance; however, the primary goal for the majority of hybrid-AM processes is to improve part quality and part performance rather than improve processing. Hybrid-AM processes are typically a cyclic process chain and are distinguished from postprocessing operations that do not meet the fully coupled criterion. Secondary processes and energy sources include subtractive and transformative manufacturing technologies, such as machining, remelting, peening, rolling, and friction stir processing (FSP). As interest in hybrid-AM grows, new economic and sustainability tools are needed as well as sensing technologies that better facilitate hybrid processing. Hybrid-AM has ushered in the next evolutionary step in AM and has the potential to profoundly change the way goods are manufactured.

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Finishing operations in the metal working industry represent a critical and expensive phase of the overall production process. A new process called Abrasive Flow Machining (AFM) promises to provide the accuracy, efficiency, economy, and the possibility of effective automation needed by the manufacturing community. The AFM process is still in its infancy in many respects. The process mechanism, parametric relationships, surface integrity, process control issues have not been effectively addressed. This paper presents preliminary results of an investigation into some aspects of the AFM process performance, surface characterization, and process modeling. The effect of process input parameters (such as media viscosity, extrusion pressure, and number of cycles) on the process performance parameters (metal removal rate and surface finish) are discussed. A stochastic modeling and analysis technique called Data Dependent Systems (DDS) has been used to study AFM generated surface. The Green’s function of the AFM surface profile models provides a “characteristic shape” that is the superimposition of two exponentials. The analysis of autocovariance of the surface profile data also indicates the presence of two real roots. The pseudo-frequencies associated with these two real roots have been linked to the path of the abrasive grains and to the cutting edges of the grain. Furthermore, expressions have been proposed for estimating the abrasive grain wear and the number of grains actively involved in cutting with a view towards developing indicators of media batch life. A brief introduction to the AFM process and related research is also included in this paper.

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