N-version Design vs. One Good Version

Evidence indicates that n-version development techniques are more reliable than producing one "good" version-and cost effective in the long run. The author concludes that diverse, independent channels used in parallel are significantly superior to even the current state of the art, especially in situations where cost of failure is high

Systematic review of the effect of individual and combined nutrition and exercise interventions on weight, adiposity and metabolic outcomes after delivery: evidence for developing behavioral guidelines for post-partum weight control

BACKGROUND: Post-partum weight retention contributes to the risk of chronic obesity and metabolic alterations. We conducted a systematic review of randomized controlled trials (RCTs) on the effect of post-partum nutrition and exercise interventions on weight loss and metabolic outcomes. DATA SOURCES: Four electronic databases were searched from inception to January, 2012. Two investigators reviewed titles and abstracts, performed data abstraction on full articles and assessed study quality. METHODS: We included RCTs comparing nutrition, exercise or combined nutrition and exercise interventions with a control condition. Thirteen studies met our inclusion criteria (N = 1,310 participants). Data were abstracted on study characteristics, intervention components, enrollment period, and length of follow-up. Outcomes of interest included weight, adiposity, cardio-metabolic measures (glucose, lipids) and obesity-related inflammatory markers. RESULTS: Nine trials compared combined interventions to standard post-partum care; three trials assessed the effect of exercise interventions, one trial evaluated a nutrition-only intervention. Four good quality RCTs on combined interventions had inconsistent findings, with the larger RCT (N = 450) reporting no difference in weight between groups. Four fair-to good quality RCTs reported greater weight loss in the combined intervention group vs. standard care, ranging from 0.17 kg to 4.9 kg. Results from exercise only interventions were inconclusive. Evidence for nutrition only interventions was insufficient. There was insufficient evidence for the effect of post-partum interventions on metabolic risk factors and inflammatory biomarkers. CONCLUSIONS: Combined nutrition and exercise interventions can achieve weight loss, but evidence is limited due to a small number of trials and limitations in study design. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/1471-2393-14-319) contains supplementary material, which is available to authorized users

Life satisfaction questionnaire (Lisat-9): reliability and validity for patients with acquired brain injury

The aim of this study was to determine the reliability and discriminant validity of the Dutch version of the life satisfaction questionnaire (Lisat-9 DV) to assess patients with an acquired brain injury. The reliability study used a test-retest design, and the validity study used a cross-sectional design. The setting was the general rehabilitation centre. There were 159 patients over 18 years of age, with an acquired brain injury, in the chronic phase. The main outcome measures were weighted kappa of test and retest data on the nine questions of the Lisat-9 DV and significance levels of differences between subgroups of patients who are expected to differ in terms of Lisat-9 scores, on the basis of other instruments. The results were as follows: the reliability was moderate, with the weighted kappa ranging from 0.41 to 0.64. In terms of validity, subgroups of patients who were expected to differ in terms of the Lisat-9 domains did indeed differ significantly, except for the difference in the Lisat score for 'contact with friends and acquaintances' between subgroups defined by higher or lower scores on the corresponding domain of the Frenchay Activities Index. As there was a plausible explanation for not finding a significant difference between subgroups defined by one of the Frenchay Activities Index domains and significant differences were found between the subgroups defined by other instruments corresponding to the same domain, we conclude that the discriminant validity is good. The reliability was not clearly affected by cognitive disorder or aphasia. The conclusions were that the reliability of the Lisat-9 DV for patients with an acquired brain injury was moderate; the discriminant validity was good

Collaborative video searching on a tabletop

Almost all system and application design for multimedia systems is based around a single user working in isolation to perform some task yet much of the work for which we use computers to help us, is based on working collaboratively with colleagues. Groupware systems do support user collaboration but typically this is supported through software and users still physically work independently. Tabletop systems, such as the DiamondTouch from MERL, are interface devices which support direct user collaboration on a tabletop. When a tabletop is used as the interface for a multimedia system, such as a video search system, then this kind of direct collaboration raises many questions for system design. In this paper we present a tabletop system for supporting a pair of users in a video search task and we evaluate the system not only in terms of search performance but also in terms of user–user interaction and how different user personalities within each pair of searchers impacts search performance and user interaction. Incorporating the user into the system evaluation as we have done here reveals several interesting results and has important ramifications for the design of a multimedia search system

Disentangling the European airlines efficiency puzzle: a network data envelopment analysis approach

© 2015 Elsevier Ltd. In recent years the European airline industry has undergone critical restructuring. It has evolved from a highly regulated market predominantly operated by national airlines to a dynamic, liberalized industry where airline firms compete freely on prices, routes, and frequencies. Although several studies have analyzed performance issues for European airlines using a variety of efficiency measurement methods, virtually none of them has considered two-stage alternatives - not only in this particular European context but in the airline industry in general. We extend the aims of previous contributions by considering a network Data Envelopment Analysis (network DEA) approach which comprises two sub-technologies that can share part of the inputs. Results show that, in general, most of the inefficiencies are generated in the first stage of the analysis. However, when considering different types of carriers several differences emerge - most of the low-cost carriers' inefficiencies are confined to the first stage. Results also show a dynamic component, since performance differed across types of airlines during the decade 2000-2010

Experimental comparison of control strategies for trajectory tracking for mobile robots

The purpose of this paper is to implement, test and compare the performance of different control strategies for tracking trajectory for mobile robots. The control strategies used are based on linear algebra, PID controller and on a sliding mode controller. Each control scheme is developed taking into consideration the model of the robot. The linear algebra approaches take into account the complete kinematic model of the robot; and the PID and the sliding mode controller use a reduced order model, which is obtained considering the mobile robot platform as a black-box. All the controllers are tested and compared, firstly by simulations and then, by using a Pioneer 3DX robot in field experiments.Fil: Capito, Linda. Escuela Politécnica Nacional; EcuadorFil: Proaño, Pablo. Escuela Politécnica Nacional; EcuadorFil: Camacho, Oscar. Escuela Politécnica Nacional; EcuadorFil: Rosales, Andrés. Escuela Politécnica Nacional; EcuadorFil: Scaglia, Gustavo Juan Eduardo. Universidad Nacional de San Juan. Facultad de Ingeniería. Instituto de Ingeniería Química; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan; Argentin

Evidence-Based Psychosocial Treatments for Pediatric Body-Focused Repetitive Behavior Disorders

Habits, such as hair pulling and thumb sucking, have recently been grouped into a category of clinical conditions called body-focused repetitive behavior disorders (BFRBDs). These behaviors are common in children and, at extreme levels, can cause physical and psychological damage. This article reviews the evidence base for psychosocial treatment of pediatric BFRBDs. A review of academic databases and published reviews revealed 60 studies on psychosocial treatments for pediatric BFRBDs, 23 of which were deemed suitable for review. Based on stringent methodological and evidence base criteria, we provided recommendations for each specific BFRBD. Individual behavior therapy proved probably efficacious for thumb sucking, possibly efficacious for several conditions, and experimental for nail biting. Individual and multicomponent cognitive-behavioral therapy was named experimental for trichotillomania and nail biting, respectively. No treatment met criteria for well-established status in the treatment of any BFRBD. Recommendations for clinicians are discussed. Reasons for the limitations of existing research in children and adolescents are explored. Several recommendations are presented for future pediatric treatment research on BFRBDs

Capturing in-situ Feelings and Experiences of Public Transit Riders Using Smartphones

High-density urban environments are susceptible to ever-growing traffic congestion issues, which speaks to the importance of implementing and maintaining effective and sustainable transportation networks. While transit oriented developments offer the potential to help mitigate traffic congestion issues, transit networks ought to be safe and reliable for ideal transit-user communities. As such, it is imperative to capture meaningful data regarding transit experiences, and deduce how transit networks can be enhanced or modified to continually maintain ideal transit experiences. Historically speaking, it has been relatively tricky to measure how people feel whilst using public transportation, without leaning on recall memory to explain such phenomena. Recall memory can be vague and is often less detailed than recording in-situ observations of the transit-user community. This thesis explores the feasibility of using smartphones to capture meaningful in-situ data to leverage the benefits of the Experience Sampling Method (ESM), while also addressing some limitations. Students travelled along Grand River Transit bus routes in Waterloo, Ontario from Wilfrid Laurier University to Conestoga Mall and back using alternate routes. The mobile survey captured qualitative and quantitative data from 145 students to explore variations in wellbeing, and the extent to which environmental variables can influence transit experiences. There were many findings to consider for future research, especially the overall role anxiety played on transit experiences. In addition, the results indicate that the methodology is appropriate for further research, and can be applied to a wide range of research topics. In particular, it is recommended that a similar study be applied to a much larger, and more representative sample of the transit-user community. Future considerations are discussed as key considerations to leverage the benefits of ESM research, and the promise it can bring towards the enhancement of transit experiences and the cohesion of transit-user communities