On the optimality of two-stage state estimation in the presence ofrandom bias

Sufficient conditions for the optimality of a two-stage state estimator in the presence of random bias are derived. Under an algebraic constraint on the correlation between the state and bias process noises, the optimal estimate of the system state can be obtained as a linear combination of the output of the first stage (a bias-free filter) and the second stage (a bias filter). Because the algebraic constraint is restrictive in practice, the results indirectly indicate that for most practical systems the proposed solution to the two-stage estimation problem will be suboptimal     

Adaptive resource management in middleware: a survey

Current middleware technologies cannot meet the demands of new application areas, such as embedded and mobile systems, that require mechanisms for dealing with a changing environment. This article reviews several approaches for providing adaptive resource management for middleware. Current middleware technologies, such as the Common Object Request Broker Architecture (CORBA) and .NET (http://msdn.microsoft.com/net), mask system and network heterogeneity problems and alleviate the inherent complexity of distributed systems in many application areas. However, the recent emergence of new application areas for middleware, such as embedded systems, real-time systems, and multimedia, imposes challenges that few existing middleware platforms can meet. In particular, because they impose greater resource-sharing and dynamism demands, these application areas require more complex and sophisticated middleware. Resource sharing must be controlled and predictable to ensure that activities running on the same middleware instance have adequate resources.     

Impaired reversal but intact acquisition: Probabilistic response reversal deficits in adult individuals with psychopathy.

The performance of adult psychopathic individuals on a novel response reversal task involving 2 reward-punishment contingencies (100-0 and 80-20) was investigated. In line with predictions, adults with psychopathy presented with impairment on the response reversal component but not on the acquisition component of this task. This selective impairment for response reversal was seen for both reward-punishment contingencies and was related to the tendency of individuals with psychopathy to be less likely to stay with a rewarded correct response to a stimulus on the subsequent presentation of that stimulus. Results are discussed with reference to current models of the development of psychopathy. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

L2imbo: A distributed systems platform for mobile computing

Mobile computing environments increasingly consist of a range of supporting technologies offering a diverse set of capabilities to applications and end-systems. Such environments are characterised by sudden and dramatic changes in the quality-of-service (QoS) available to applications and users. Recent work has shown that distributed systems platforms can assist applications to take advantage of these changes in QoS and, more specifically, facilitate applications to adapt to their environment. However, the current state-of-the-art in these platforms reflects their fixed network origins through their choice of synchronous connection-oriented communications paradigms. In this paper we argue that these paradigms are not well suited to operation in the emerging mobile environments. Furthermore, we offer an alternative programming paradigm based on tuple spaces which, we believe, offers a number of benefits within a mobile context. The paper presents the design, implementation and evaluation of a new platform based on this paradigm. This revised version was published online in June 2006 with corrections to the Cover Date.     

Physical activity patterns associated with cardiorespiratory fitness and reduced mortality: the Aerobics Center Longitudinal Study

OBJECTIVES: This study examined cross sectionally the physical activity patterns associated with low, moderate, and high levels of cardiorespiratory fitness. METHODS: Physical activity was assessed by questionnaire in a clinic population of 13,444 men and 3972 women 20 to 87 years of age. Estimated energy expenditure (kcal.wk-1) and volume (min.wk-1) of reported activities were calculated among individuals at low, moderate, and high fitness levels (assessed by maximal exercise tests). RESULTS: Average leisure time energy expenditures of 525 to 1650 kcal.wk-1 for men and 420 to 1260 kcal.wk-1 for women were associated with moderate to high levels of fitness. These levels of energy expenditure can be achieved with a brisk walk of approximately 30 minutes on most days of the week. In fact, men in the moderate and high fitness categories walked between 130 and 138 min.wk-1, and women in these categories walked between 148 and 167 min.wk-1. CONCLUSIONS: Most individuals should be able to achieve these physical activity goals and thus attain a cardiorespiratory fitness level sufficient to result in substantial health benefits.     

Psychosocial functioning of young adults with cystic fibrosis and their families

BACKGROUND: The psychosocial functioning of adolescents and young adults with cystic fibrosis still living in the parental home was investigated. With its proven genetic aetiology cystic fibrosis is an ideal model with which to assess the impact of a chronic and life threatening disorder on family and individual psychological and social functioning. METHODS: Twenty nine patients with cystic fibrosis and their families were compared with those of 27 patients with anorexia nervosa and 31 well controls. Assessments were made using self reporting, interview, and observational methods. RESULTS: Most patients with cystic fibrosis were in robust psychological health and only differed from their healthy peers in that they were much less likely to be in employment. Mothers of patients with cystic fibrosis or anorexia nervosa were more likely than the mothers of the well group to be emotionally distressed, although this was not so for fathers. Young people in both illness groups were more likely to have parents with high levels of expressed emotion. Most families of patients with cystic fibrosis had good problem solving abilities. CONCLUSIONS: In spite of the burden of illness in cystic fibrosis psychological functioning in many respects matches that of well young people.     

Indium channel implant for improved short-channel behavior ofsubmicrometer NMOSFETs

Indium has been used as an alternative channel implant in submicrometer-channel Si MOSFETs in order to obtain highly nonuniform channel doping. Superior device characteristics have been obtained down to 0.17-μm channel length. The device characteristics have been compared to those of uniform boron-implanted short-channel MOSFETs used in a 0.25-μm CMOS technology. Results indicate that NMOSFETs with nonuniform channel doping obtained with indium have superior short-channel effect (SCE) when compared to NMOSFETs with uniformly (boron) doped channel     

Spectroscopic investigation of hydrocellulose phenylosazones in cadoxen solution

Solutions of hydrocellulose phenylosazone in cadoxen are stable when oxygen is excluded. In the presence of oxygen, the absorption spectrum changes, but the change is partially reversible when nitrogen is bubbled through the oxidized solution. It is probable that a hydroperoxide of the hydrocellulose phenylosazone is formed initially and is then decomposed by the basic solvent. The work indicates the importance of using deoxygenated solvents and working in an oxygen-free atmosphere when preparing cadoxen solutions of hydrocellulose phenylosazone.     

Biopterin derivatives in human body fluids and tissues

Levels of biopterin derivatives in urine, serum, milk, cerebrospinal fluid, brain, and liver have been measured with the Crithidia fasciculata assay. Normal levels in serum and urine have been given and compared with those in a number of benign and malignant proliferative disorders, phenylketonuria, kidney disease, Parkinson's disease, schizophrenia, controlled epilepsy, rheumatoid arthritis, and pernicious anaemia. The active component of Crithidia factor in serum was 7,8-dihydrobiopterin. Tissue, urine, and some serum samples contained two active materials, the principal one being 7,8-dihydrobiopterin; a minor constituent was probably tetrahydrobiopterin. Serum biopterin levels following methotrexate administration were raised and subsequent administration of folic acid and 5-formyltetrahydrofolic acid further increased serum levels of biopterin derivatives; this was in contrast to the total absence of response to oral folates without prior methotrexate and to 5-methyltetrahydrofolic acid either with or without methotrexate being given.