Prospective, Randomized Assessment of Transfer of Training (ToT) and Transfer Effectiveness Ratio (TER) of Virtual Reality Simulation Training for Laparoscopic Skill Acquisition

OBJECTIVES:: We assessed the effectiveness of ToT from VR laparoscopic simulation training in 2 studies. In a second study, we also assessed the TER. ToT is a detectable performance improvement between equivalent groups, and TER is the observed percentage performance differences between 2 matched groups carrying out the same task but with 1 group pretrained on VR simulation. Concordance between simulated and in-vivo procedure performance was also assessed. DESIGN:: Prospective, randomized, and blinded. PARTICIPANTS:: In Study 1, experienced laparoscopic surgeons (n = 195) and in Study 2 laparoscopic novices (n = 30) were randomized to either train on VR simulation before completing an equivalent real-world task or complete the real-world task only. RESULTS:: Experienced laparoscopic surgeons and novices who trained on the simulator performed significantly better than their controls, thus demonstrating ToT. Their performance showed a TER between 7% and 42% from the virtual to the real tasks. Simulation training impacted most on procedural error reduction in both studies (32- 42%). The correlation observed between the VR and real-world task performance was r > 0·96 (Study 2). CONCLUSIONS:: VR simulation training offers a powerful and effective platform for training safer skills.

Optimizing Research on End-of-Life Care for Seniors:The Collective New Emerging Team on End of Life Care for Seniors University of Ottawa, Institute of Palliative Care

Background: End-of-life care for seniors is an important and neglected area of research. The University of Ottawa Institute of Palliative Care has expanded its research capacity by developing a Canadian Institutes of Health Research (CIHR) funded new emerging team on end-of-life care for seniors. This initiative brings together an interdisciplinary team of researchers from palliative care and geriatrics to develop a comprehensive program of research. Methods: 1) A variety of investigators from the fields of palliative care and geriatrics and disciplines of epidemiology, medicine, nursing, psychology and social work will collaborate on the development of a research agenda focussed on end-of-life care for seniors. 2) The conceptual model for the research program consists of 4 broad interrelated domains that are congruent with the CIHR themes of health services, clinical issues, population health and psychosocial, cultural, spiritual and ethical issues; this framework will guide the research program and all studies emanating from the program. 3) Research studies will focus on 5 areas of inquiry that are central to end-of-life care for seniors: palliative end-of-life care for rural seniors, care settings, burden, role of volunteers, and delirium. Results: This new team has the potential to obtain peer-reviewed funding, recruit and train a new generation of researchers, and build a network of concerned researchers. Conclusions: The new team should ultimately contribute to an improved quality of care for seniors who are approaching death.

An Investigation Into Features For Multi-View Lipreading

For the first time in this paper we present results showing the effect of speaker head pose angle on automatic lip-reading performance over a wide range of closely spaced angles. We analyse the effect head pose has upon the features themselves and show that by selecting coefficients with minimum variance w.r.t. pose angle, recognition performance can be improved when train-test pose angles differ. Experiments are conducted using the initial phase of a unique multi view Audio-Visual database designed specifically for research and development of pose-invariant lip-reading systems. We firstly show that it is the higher order horizontal spatial frequency components that become most detrimental as the pose deviates. Secondly we assess the performance of different feature selection masks across a range of pose angles including a new mask based on Minimum Cross-Pose Variance coefficients. We report a relative improvement of 50% in Word Error Rate when using our selection mask over a common energy based selection during profile view lip-reading.

Multibody modelling of gabion beams for impact applications

Gabions are stone-filled wire containers which are frequently used as retaining walls. However, due to their high mass, relatively low cost and visual appeal, a row of single gabion blocks, joined at the ends, has the potential to be used as a roadside impact absorption device where traditional steel or concrete devices may not be suitable. To evaluate such application, the shear and bending deformation of gabions under vehicle impact need to be investigated. In this paper, the shear response of a single gabion block is analytically modelled and a gabion beam multibody model is developed using a discretisation method to capture the deformability of the gabion structure. The material properties of the gabion beam are adopted from experimental values available in the literature and the modelling is statically validated over a three-point bending test and a distributed loading test. The results show that the discretised multibody modelling can be effectively used to describe the static deformation behaviour of gabion blocks.

Optimization of FRT Active Power Performance of a DFIG during Transient Grid Faults

Optimal fault ride-through (FRT) conditions for a doubly-fed induction generator (DFIG) during a transient grid fault are analyzed with special emphasis on improving the active power generation profile. The transition states due to crowbar activation during transient faults are investigated to exploit the maximum power during the fault and post-fault period. It has been identified that operating slip, severity of fault and crowbar resistance have a direct impact on the power capability of a DFIG, and crowbar resistance can be chosen to optimize the power capability. It has been further shown that an extended crowbar period can deliver enhanced inertial response following the transient fault. The converter protection and drive train dynamics have also been analyzed while choosing the optimum crowbar resistance and delivering enhanced inertial support for an extended crowbar period.

Staffing, status and subject knowledge: what does the construction of citizenship as a new curriculum subject in England tell us about the nature of school subjects?

Almost a decade ago, the new subject of citizenship was created in the English National Curriculum and several universities were funded to train teachers in this new subject. This presented a rare challenge, namely how to train people to teach a subject that did not exist in schools, and in which they were unlikely to have a specialist degree. In this article we have taken the opportunity afforded by the
tenth birthday of the report in which Crick recommended this curriculum reform to reflect on that experience from the perspective of teacher educators. Through reflecting on the case study of citizenship education in England we highlight several themes that are of more general interest to teacher educators. The key issues that have emerged in this case study relate to the general problems of translating central policy into classroom practice; the nature and aims of subjects in the curriculum; and the identities of teachers in secondary schools. The article illustrates how teacher educators responded to the formidable challenge of creating (or at least contributing to) a new subject and a subject community.

Vichy, un passé qui ne passe pas ?

La Seconde Guerre mondiale demeure très présente dans les mémoires des Français qui seraient plongés dans une « phase obsessionnelle » depuis le début des années 1970 selon l’historien Henry Rousso. Notre étude se propose de vérifier dans quelle mesure cela reste vrai de nos jours. Elle entend le faire non pas en se basant sur ses occurrences dans la presse ou dans les médias – ce qui, paradoxalement, pourrait ne faire ressortir que ce qui est du domaine de l’épidermique – mais indirectement, à travers les romans et, plus précisément, les best-sellers qui sont, selon de nombreux critiques, des miroirs privilégiés de l’inconscient collectif ou de l’imaginaire d’une époque que, en retour, ils contribuent à façonner. Nous distinguerons quatre phases depuis 1945. Or, les best-sellers contemporains, ceux de la quatrième et dernière phase, présentent nombre de caractéristiques communes qui suggèrent que ce passé difficile est bel et bien en train de passer.

A static test method to assess swivel seat strength in frontal impact

Mechanical swivel seat adaptations are a key aftermarket disability modification to any small-to medium-sized passenger vehicle. However, the crashworthiness of these devices is currently unregulated and the existing 20g dynamic sled testing approach is prohibitively expensive for prototype assessment purposes. In this paper, an alternative quasi-static test method for swivel seat assessment is presented, and two different approaches (free-body diagram and multibody modelling) validated through published experimental data are developed to determine the appropriate loading conditions to apply in the quasi-static testing.Results show the two theoretical approaches can give similar results for estimating the quasi-static loading conditions, and this depends on the seatbelt configuration. Application of the approach to quasi-static testing of both conventional seats and those with integrated seat belts showed the approach to be successful and easy to apply. It is proposed that this method be used by swivel seat designers to assess new prototypes prior to final validation via the traditional 20g sled test.

Gabions: evaluation of potential as low-cost roadside barriers

This paper evaluates the potential of gabions as roadside safety barriers. Gabions have the capacity to blend into natural landscape, suggesting that they could be used as a safety barrier for low-volume road in scenic environments. In fact, gabions have already been used for this purpose in Nepal, but the impact response was not evaluated. This paper reports on numerical and experimental investigations performed on a new gabion barrier prototype. To assess the potential use as a roadside barrier, the optimal gabion unit size and mass were investigated using multibody analysis and four sets of 1:4 scaled crash tests were carried out to study the local vehicle-barrier interaction. The barrier prototype was then finalised and subjected to a TB31 crash test according to the European EN1317 standard for N1 safety barriers. The test resulted in a failure due to the rollover of the vehicle and tearing of the gabion mesh yielding a large working width. It was found that although the system potentially has the necessary mass to contain a vehicle, the barrier front face does not have the necessary stiffness and strength to contain the gabion stone filling and hence redirect the vehicle. In the EN1317 test, the gabion barrier acted as a ramp for the impacting vehicle, causing rollover. 

Testing Tidal Turbines - Part 1: Steady Towing Tests vs Tidal Moored Tests

Tidal turbines have been tested extensively at many scales in steady state flow. Testing medium- or full-scale devices in turbulent flow has been less thoroughly examined. The differences between turbine performances in these two different states are needed for testing method verification and numerical model validation. The work in this paper documents the performance of a 1/10 scale turbine in steady state pushing tests and tidal moored tests. The overall performance of the device appears to decrease with turbulent flow, though there is increased data scatter and therefore, reduced uncertainty. At maximum power performance, as velocity increases the mechanical power and electrical power reduction from steady to unsteady flow increases. The drive train conversion efficiency also decreases. This infers that the performance for this turbine design is affected by the presence of turbulent flow.

Design of Scaled Bridge Prototype for Energy Harvesting Testing

Energy harvesting from ambient vibration is a promising field, especially for applications in larger infrastructures such as bridges. These structures are more frequently monitored for damage detection because of their extended life, increased traffic load and environmental deterioration. In this regard, the possibility of sourcing the power necessary for the sensors from devices embedded in the structure, thus cutting the cost due to the management of battery replacing over the lifespan of the structure, is particularly attracting. Among others, piezoelectric devices have proven to be especially effective and easy to apply since they can be bonded to existing host structure. For these devices the energy harvesting capacity is achieved directly from the variation in the strain conditions from the surface of the structure. However these systems need to undergo significant research for optimisation of their harvesting capacity and for assessing the feasibility of application to various ranges of bridge span and load. In this regard scaled bridge prototypes can be effectively used not only to assess numerical models and studies in an inexpensive and repeatable way but also to test the electronic devices under realistic field conditions. In this paper the theory of physical similitude is applied to the design of bridge beams with embedded energy harvesting systems and health monitoring sensors. It will show both how bridge beams can be scaled in such a way to apply and test energy harvesting systems and 2) how experimental data from existing bridges can be applied to prototypes in a laboratory environment. The study will be used for assessing the reliability of the system over a train bridge case study undergoing a set load cycles and induced localised damage.

Video Event Recognition by Dempster-Shafer Theory

This paper presents an event recognition framework, based on Dempster-Shafer theory, that combines evidence of events from low-level computer vision analytics. The proposed method employing evidential network modelling of composite events, is able to represent uncertainty of event output from low level video analysis and infer high level events with semantic meaning along with degrees of belief. The method has been evaluated on videos taken of subjects entering and leaving a seated area. This has relevance to a number of transport scenarios, such as onboard buses and trains, and also in train stations and airports. Recognition results of 78% and 100% for four composite events are encouraging.

165/183 GHz FSS for the MetOp Second Generation Microwave Sounder Instrument

This paper reports the design of a Frequency Selective Surface (FSS) which simultaneously allows transmission of 175.3 – 191.3 GHz radiation and rejection from 164 - 167 GHz with a loss <0.5 dB for TE wave polarization at 45° incidence. The state-of-the art filter consists of three air spaced perforated screens with unit cells that are composed of nested resonant slots. The FSS satisfies the stringent electromagnetic performance requirements for signal demultiplexing in the quasi-optical feed train of the Microwave Sounder (MWS) instrument which is under development for the MetOp-SG mission.

Predicting forest attributes In southeast Alaska using artificial neural networks

Artificial neural network (ANN) methods are used to predict forest characteristics. The data source is the Southeast Alaska (SEAK) Grid Inventory, a ground survey compiled by the USDA Forest Service at several thousand sites. The main objective of this article is to predict characteristics at unsurveyed locations between grid sites. A secondary objective is to evaluate the relative performance of different ANNs. Data from the grid sites are used to train six ANNs: multilayer perceptron, fuzzy ARTMAP, probabilistic, generalized regression, radial basis function, and learning vector quantization. A classification and regression tree method is used for comparison. Topographic variables are used to construct models: latitude and longitude coordinates, elevation, slope, and aspect. The models classify three forest characteristics: crown closure, species land cover, and tree size/structure. Models are constructed using n-fold cross-validation. Predictive accuracy is calculated using a method that accounts for the influence of misclassification as well as measuring correct classifications. The probabilistic and generalized regression networks are found to be the most accurate. The predictions of the ANN models are compared with a classification of the Tongass national forest in southeast Alaska based on the interpretation of satellite imagery and are found to be of similar accuracy.

Predicting the crushing behaviour of composite material using high-fidelity finite element modelling

The capability to numerically model the crushing behaviour of composite structures will enable the efficient design of structures with high specific energy absorption capacity. This is particularly relevant to the aerospace and automotive industries where cabin structures need to be shown to be crashworthy. In this paper, a three-dimensional damage model is presented, which accurately represents the behaviour of composite laminates under crush loading. Both intralaminar and interlaminar failure mechanisms are taken into account. The crush damage model was implemented in ABAQUS/Explicit as a VUMAT subroutine. Numerical predictions are shown to agree well with experimental results, accurately capturing the intralaminar and interlaminar damage for a range of stacking sequences, triggers and composite materials. The use of measured material parameters required by the numerical models, without the need to ‘calibrate’ this input data, demonstrates this computational tool's predictive capabilities