Programmable differential brake for passive haptics

This paper outlines work on a novel programmable braking system, which is widely applicable to most passive haptic applications and benefits from a simple design, theoretically infinite positional resolution and the ability to generate stiff collision forces, without the need for any explicit force measurements. Results are also given of a preliminary concept demonstrator which is based on a simple 2-Degrees-Of-Freedom (DOF) Revolute–Revolute (RR) manipulator incorporating the programmable brakes. Performance measures for the joint, as well as figures describing the ability of the 2-DOF prototype to constrain the end effector motion to a plane and a circle, are also provided.     

Cognitive-bias toward gaming-related words and disinhibition in World of Warcraft gamers

This study investigated cognitive biases toward gaming-related words and differences in cognitive performance among twelve World of Warcraft players (WWP) and thirty non-players (NP). We measured response to valenced common English and WoW jargon words using a computer-based go/no-go task. Sometimes positive valence words were the targets for the ‘go’ response, with negative-valence words as the distracters, sometimes the reverse. Target discrimination (d′) and response disinhibition (C) were calculated using a signal detection analysis. Based on questionnaire responses, there were no differences between groups in depression, anxiety, smoking or drinking, but WWP reported significantly more screen and gaming time (17.31 h/week versus 4.12 among NP). WWP had faster reaction time (RT) and better discrimination of targets from distracters (high d′) but also showed higher disinhibition (low C). WWP also showed cognitive-bias toward game-related words in the form of higher d′ for WoW jargon than common English and more disinhibition to positive-valence WoW jargon. Similar to past studies which have found alcoholics to have cognitive biases toward alcohol-related words, WWP who play frequently showed cognitive biases toward words related to the World of Warcraft game.     

Evidential reasoning using extended fuzzy Dempster–Shafer theory for handling various facets of information deficiency

This work investigates the problem of combining deficient evidence for the purpose of quality assessment. The main focus of the work is modeling vagueness, ambiguity, and local nonspecificity in information within a unified approach. We introduce an extended fuzzy Dempster–Shafer scheme based on the simultaneous use of fuzzy interval‐grade and interval‐valued belief degree (IGIB). The latter facilitates modeling of uncertainties in terms of local ignorance associated with expert knowledge, whereas the former allows for handling the lack of information on belief degree assignments. Also, generalized fuzzy sets can be readily transformed into the proposed fuzzy IGIB structure. The reasoning for quality assessment is performed by solving nonlinear optimization problems on fuzzy Dempster–Shafer paradigm for the fuzzy IGIB structure. The application of the proposed inference method is investigated by designing a reasoning scheme for water quality monitoring and validated through the experimental data available for different sampling points in a water distribution network. © 2011 Wiley Periodicals, Inc.     

Exploring alternatives for transition verification

When an implementation under test (IUT) is state-based, and its expected abstract behavior is given in terms of a finite state machine (FSM), a checking sequence generated from a specification FSM and applied to an IUT for testing can provide us with high-level confidence in the correct functional behavior of our implementation. One of the issues here is to generate efficient checking sequences in terms of their lengths. As a major characteristics, a checking sequence must contain all β-sequences for transition verification. In this paper, we discuss the possibility of reducing the lengths of checking sequences by making use of the invertible transitions in the specification FSM to increase the choice of β-sequences to be considered for checking sequence generation. We present a sufficient condition for adopting alternative β-sequences and illustrate typical ways of incorporating these alternative β-sequences into existing methods for checking sequence generation to reduce the lengths. Compared to the direct use of three existing methods, our experiments show that most of the time the saving gained by adopting alternative β-sequences falls in the range of 10–40%.     

Benchmarking stereo-derived DSMs to lidar by land cover and slope for resource development in northern Ontario,Canada

Topographic and elevation data are essential in the development of supporting infrastructure around mining sites. The de facto standard for acquiring elevation data is through light detection and ranging (lidar). The high labour and monetary cost of acquiring lidar has fostered more cost-effective approaches for creating elevation models that use stereo photogrammetry. To assess the accuracy of stereo-photogrammetry-derived elevation models and their potential application, we benchmark satellite (Worldview-2) and aircraft (South Central Ontario Orthoimagery Project; SCOOP) stereo-derived digital surface models (DSMs) against a lidar-derived DSM. Our results show that both stereo-derived DSMs have strong monotonic correlations with lidar across a range of land-cover types and slopes. The overall vertical accuracy of Worldview-2 and SCOOP DSMs are similar and do not meet the United States National Digital Elevation Program (NDEP) standards. However, accuracy assessment across land-cover types and slope categories show that specific land cover types (i.e. grass, row crops/pasture, sparse vegetation and marsh) on gently sloping terrain compare well to lidar data and meet NDEP accuracy standards. We situate the presented research in the context of northern resource development and discuss opportunities to improve the vertical accuracy of stereo-derived DSMs, for example, through unmanned aerial systems.     

Automatic Schaeffer's gestures recognition system

Schaeffer's sign language consists of a reduced set of gestures designed to help children with autism or cognitive learning disabilities to develop adequate communication skills. Our automatic recognition system for Schaeffer's gesture language uses the information provided by an RGB‐D camera to capture body motion and recognize gestures using dynamic time warping combined with k‐nearest neighbors methods. The learning process is reinforced by the interaction with the proposed system that accelerates learning itself thus helping both children and educators. To demonstrate the validity of the system, a set of qualitative experiments with children were carried out. As a result, a system which is able to recognize a subset of 11 gestures of Schaeffer's sign language online was achieved.     

Numerical solution of the nonlinear Schrödinger equation,starting from the scattering data

Starting from the scattering data, the initial-value problem for the focusing nonlinear Schrödinger equation is solved numerically by following the path of the inverse scattering transform. The numerical results of an extensive experimentation suggest that: (a) our method is very effective, whenever the scattering data are analytically known; (b) the split-step Fourier method is not really effective if the exact solution is not smooth enough.     

Standard process monitoring and traceability programming in collaborative CAD/CAM/CNC manufacturing scenarios

The paper focuses on collaborative STEP-based CAD/CAM/CNC supply chains to program and automate machining process data monitoring and traceability activities. A traceability interface (traceability nc_functions) is defined for the new CNC programming standard ISO STEP-NC. CAM systems will be able to program monitoring and data access activities by inserting traceability nc_function calls in CNC programs. On the shop floor, controllers will automatically interpret these nc_functions to access process data while machining and will relate data records with the corresponding machining operations in a STEP-NC part program. With both types of information—process data and standard machining program (STEP-NC part program)—spread and technologically heterogeneous engineering systems will have full knowledge about what has happened in production. Traceability data access automation will assure data reliability. The paper describes a traceability scenario where standards such as MTConnect and ISA-95 support, rather than interfere with, the STEP-NC traceability proposal.     

Modeling the glucose regulatory system in extreme preterm infants

Background

Premature infants represent a significant proportion of the neonatal intensive care population. Blood glucose homeostasis in this group is often disturbed by immaturity of endogenous regulatory systems and the stress of their condition. Hypo- and hyperglycemia are frequently reported in very low birth weight infants, and more mature infants often experience low levels of glycemia. A model capturing the unique fundamental dynamics of the neonatal glucose regulatory system could be used to develop better blood glucose control methods.

Methods

A metabolic system model is adapted from adult critical care to the unique physiological case of the neonate. Integral-based fitting methods were used to identify time-varying insulin sensitivity and non-insulin mediated glucose uptake profiles. The clinically important predictive ability of the model was assessed by assuming insulin sensitivity was constant over prediction intervals of 1, 2 and 4 h forward and comparing model-simulated versus actual clinical glucose values for all recorded interventions. The clinical data included 1091 glucose measurements over 3567 total patient hours, along with all associated insulin and nutritional infusion data, for N = 25 total cases. Ethics approval was obtained from the Upper South A Regional Ethics Committee for this study.

Results

The identified model had a median absolute percentage error of 2.4% [IQR: 0.9-4.8%] between model-fitted and clinical glucose values. Median absolute prediction errors at 1-, 2- and 4-h intervals were 5.2% [IQR: 2.5-10.3%], 9.4% [IQR: 4.5-18.4%] and 13.6% [IQR: 6.3-27.6%] respectively.

Conclusions

The model accurately captures and predicts the fundamental dynamic behaviors of the neonatal metabolism well enough for effective clinical decision support in glycemic control. The adaptation from adult to a neonatal case is based on the data from the literature. Low prediction errors and very low fitting errors indicate that the fundamental dynamics of glucose metabolism in both premature neonates and critical care adults can be described by similar mathematical models.     

The impact of cultural differences in offshore outsourcing—Case study results from German–Indian application development projects

Offshore outsourcing to vendors in foreign countries causes unique challenges which need to be understood and managed effectively. This paper explores cultural differences in IS offshoring arrangements involving German client organizations that outsource application development activities to Indian vendors. For this purpose, a research framework is developed based on both theoretical considerations and specific empirical observations from multiple case studies. The goal is to (1) explore the nature of cultural differences in offshore outsourcing arrangements in depth and to (2) analyze the relationship between those cultural differences and offshore outsourcing success. Based on the case findings, implications and practices for the management of offshore development projects are outlined. The results indicate that cultural differences in terms of power distance, IS designer values, and an active versus passive working attitude critically affect several dimensions of relationship quality, thereby influencing offshore outsourcing success. A clear definition of roles and mechanisms, strong leadership, and an active management of culture by adapting to either the client’s or the vendor’s national culture appeared to be effective ways to manage cultural differences.