Simple and efficient moving horizon estimation based on the fast gradient method

By now many results with respect to the fast and efficient implementation of model predictive control exist. However, for moving horizon estimation, only a few results are available. We present a simple solution algorithm tailored to moving horizon estimation of linear, discrete time systems. In a first step the problem is reformulated such that only the states remain as optimization variables, i.e. process and measurement noise are eliminated from the optimization problem. This reformulation enables the use of the fast gradient method, which has recently received a lot of attention for the solution of model predictive control problems. In contrast to the model predictive control case, the Hessian matrix is time- varying in moving horizon estimation, due to the time-varying nature of the arrival cost. Therefore, we outline a tailored method to compute online the lower and upper eigenvalues of the Hessian matrix required by the here considered fast gradient method. In addition, we discuss stopping criteria and various implementation details. An example illustrates the efficiency of the proposed algorithm

Identifying early intervention targets for children with autism in inclusive school settings

This study assessed play and social behavior of young children with autism in inclusive school settings to identify important targets for intervention. Data were collected for five children with autism and for typically developing peers. All children with autism received intervention in oneon-one settings but did not have individual education plan goals that provided systematic intervention for developing play and social skills in their school settings. Results indicated the children with autism and their typically developing peers played with a comparable number of stimulus items (e.g., toys), but the children with autism engaged in these activities for shorter durations. Both children with autism and their typically developing peers engaged in similar levels of social interaction with adults. However, the children with autism rarely or never engaged in social interactions with their peers, whereas the typically developing peers frequently engaged in social interactions with other children. The results suggest important targets for intervention. Identifying Early Intervention ROSY M. FREDEEN University of California, Santa Barbara A trend toward inclusion has resulted in an increased number of children with disabilities attending their neighborhood schools and being educated in the same classrooms with their typically developing peers. The values of inclusion involve providing a normalized setting for children with disabilities, where opportunities for building friendships and having role models for socialization are available (Kohler &amp

Brief Report: Question-Asking and Collateral Language Acquisition in Children with Autism

The literature suggests children with autism use communication primarily for requests and protests, and almost never for information-seeking. This study investigated whether teaching “Where” questions using intrinsic reinforcement procedures would produce the generalized use of the question, and whether concomitant improvements in related language structures, provided as answers to the children’s questions, would occur. In the context of a multiple baseline across participants design, data showed that the children could rapidly acquire and generalize the query, and that there were collateral improvements in the children’s use of language structures corresponding to the answers to the questions the children asked. The results are discussed in the context of teaching child initiations to improve linguistic competence in children with autism

HIV and People With Serious Mental Illness: The Public Sector’s Role in Reducing HIV Risk and Improving Care

Objective: The paper discusses issues related to the detection, prevention of transmission, and treatment of human immunodefiency virus (HIV) infection among persons with serious mental illness and suggests ways public mental health systems can address these issues. Methods: MEDLINE was searched from 1980 through 1998, and all pertinent references were reviewed. Results: Persons with severe mental illness are at greatly increased risk of HIV infection due to increased likelihood of high-risk sexual behaviors and injection drug use. The formidable barriers to detection and effective treatment of HIV that exist in this population can be attributed to the unique characteristics of this population, lack of knowledge and expertise among mental and physical health care providers, and fragmented mental and physical health care systems. Conclusions: In the last five years, treatments for HIV that are far more efficacious than earlier treatments have become available, making it more important for HIV infection be detected and treated among persons with serious mental illness. Public mental health systems need to implement active prevention policies and practices, educate both mental health and physical health care providers about key treatment issues, and develop effective linkages between mental and physical health care providers and systems

Projected loss of soil organic carbon in temperate agricultural soils in the 21^stcentury: effects of climate change and carbon input trends

Climate change and stagnating crop yields may cause a decline of SOC stocks in agricultural soils leading to considerable CO2 emissions and reduced agricultural productivity. Regional model-based SOC projections are needed to evaluate these potential risks. In this study, we simulated the future SOC development in cropland and grassland soils of Bavaria in the 21st century. Soils from 51 study sites representing the most important soil classes of Central Europe were fractionated and derived SOC pools were used to initialize the RothC soil carbon model. For each site, long-term C inputs were determined using the C allocation method. Model runs were performed for three different C input scenarios as a realistic range of projected yield development. Our modelling approach revealed substantial SOC decreases of 11–16% under an expected mean temperature increase of 3.3 °C assuming unchanged C inputs. For the scenario of 20% reduced C inputs, agricultural SOC stocks are projected to decline by 19–24%. Remarkably, even the optimistic scenario of 20% increased C inputs led to SOC decreases of 3–8%. Projected SOC changes largely differed among investigated soil classes. Our results indicated that C inputs have to increase by 29% to maintain present SOC stocks in agricultural soils

Augmentative and alternative communication for children with autism spectrum disorder: an evidence-based evaluation of the Language Acquisition through Motor Planning (LAMP) programme

Children diagnosed with autism spectrum disorder often have restricted verbal communication. For children who do not use functional speech, augmentative and alternative communication (AAC) devices can be an important support. We evaluated the effectiveness of one AAC programme, the Language Acquisition through Motor Planning (LAMP) using a Vantage Lite™ device as the speech output in the home and school environments. Eight children with limited communication were assessed by a speech pathologist prior to the introduction of the programme, after five weeks of training and again after a further two weeks of use of the programme, but without the supported training. The pre-/post-assessment measures revealed that all eight children made gains in the development of spontaneous communication using the device during the implementation period. Parents and teachers also reported that the gains achieved during the five-week trial were greater than those achieved in previous interventions. Two years after the completion of the study, a follow-up phone interview was completed which identified that children who received ongoing support from a LAMP-trained speech pathologist continued using the LAMP programme. As a result of this study, a specialised LAMP specific classroom was established in one of the participating schools

In-Home Training for Fathers of Children with Autism: A Follow up Study and Evaluation of Four Individual Training Components

Literature regarding fathers of children with autism remains sparse, and because mothers are the more common intervening parent, few training methods have focused on fathers. Thus, we sought to evaluate effects of in-home training directed at fathers and their ability to train mothers in the same manner in which they were trained. Fathers were taught four skills commonly associated with in-home training interventions for parents of children with autism: following the child’s lead, imitation with animation, commenting on the child, and expectant waiting. Father skills were evaluated twice a week for 12 weeks during videotaped in-home father–child play sessions. Analyses included visual inspection of graphed data and statistical analyses of father skill acquisition, mother skill acquisition, and child behaviors with both parents. A multivariate repeated measures analysis of 18 dyads revealed significant increases in frequencies of fathers’ imitation with animation, expectant waiting, and commenting on the child. Child initiating rates increased significantly as did frequencies of child non-speech vocalizations. Analysis of mothers revealed significant increases in frequencies of imitation with animation, expectant waiting, and following the child’s lead. Child behaviors had similar results for father and mother sessions. Findings are consistent with those from our first study indicating that fathers can effectively implement skills that promote father–child social interactions and that children respond positively to this approach