Color-Word Test performance and drive regulation in three vocational groups.

Performance on the Color-Word Test (CWT) has been considered to reflect individual differences in constricted-flexible control, which is a dimension of styles of controlling and expressing drives. In Part I of this study, comparisons were made among CWT performances of groups which differ in such styles: 26 mathematicians, 24 creative writers, and 25 physicians. Several intergroup differences were found, but could not be accounted for in terms of constricted-flexible control. In Part II, CWT scores were compared to independent (mostly TAT) measures of drive regulation. Results were negative. It was concluded that CWT performance is relevant to molar adaptive behavior (vocation), but constricted-flexible control does not adequately account for variance on the test. More differentiated analysis of the CWT is recommended. (18 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Designing Technology as an Embedded Resource for Troubleshooting

In this paper we describe a number of technologies which we designed to provide support for customers troubleshooting problems with their office devices. The technologies aim to support both self-conducted and expert-supported troubleshooting and to provide a seamless route from one type of support to another. The designs are grounded in the findings of an ethnographic study of a troubleshooting call centre for office devices. We examine the properties of different assemblies of people, resources, technologies and spaces to inspire design for the different troubleshooting situations. Through our fieldwork and our technology envisionments we uncovered a number of dislocations between various aspects of the troubleshooting assemblies: (1) a physical dislocation between the site of the problem and the site of problem resolution; (2) a conceptual dislocation between the users’ knowledge and the troubleshooting resources and (3) a logical dislocation between the support resources and the status of the ailing device itself. The technologies that we propose attempt to address these dislocations by embedding the troubleshooting resources in the device itself, thus harmonizing the various elements and capturing, where possible, the haecceities—the ‘just thisness’—of each particular troubleshooting situation.     

Adjoint sensitivity related to geometric parameters for mid-high frequency range vibroacoustics

Shape optimization issues under vibroacoustic criteria are considered in present paper. The adjoint-based gradient method was developed to minimize the energy density inside a cavity by changing its geometry parameters. The adjoint equations give the sensitivity information, which is subsequently used in a gradient-based minimization of a prescribed cost functional that models the energy density via Simplified Energy Method. Objective function is obtained by mapping 3D cavity surface on a 2D domain with the help of transformation function. Thus, the remeshing of the geometry is avoided and smoothness of the solution is reached. The optimization process is based on adjoint calculation of the gradient that leads to analytical expressions of the directional derivatives without additional computational cost. The proposed method is validated for the case of rectangular cavity modeled with patches of Bezier surfaces.     

Linear buckling analysis of thin-walled members combining the Generalised Beam Theory and the Finite Element Method

A finite element procedure to carry out linear buckling analysis of thin-walled members is developed on the basis of the existing Generalised Beam Theory (GBT) and constrained Finite Strip Method (cFSM). It allows designers to uncouple the buckling modes of a finite element model and, consequently, to calculate pure elastic buckling loads. The procedure can easily be applied to members with general boundary conditions subjected to compression or bending. The results obtained are rather accurate when compared to the values calculated via GBT and cFSM. As a consequence, it is demonstrated that linear buckling analyses can be performed with the Finite Element Method in a similar way as can be done with the existing GBT and cFSM procedures.     

Development of the Motivators of and Barriers to Health-Smart Behaviors Inventory.

The Motivators of and Barriers to Health-Smart Behaviors Inventory (MB-HSBI) was developed for use in identifying self-reported motivators of and barriers to the following health-promoting behaviors (called health-smart behaviors) that should occur daily to help promote health and overcome illnesses/diseases: eating a healthy breakfast, eating healthy foods and snacks, drinking healthy drinks, and engaging in physical activity. The MB-HSBI was developed through several phases as part of a multisite study on modifying and preventing obesity. A central aspect of the larger study was to identify motivators of and barriers to the targeted health-smart behaviors among African American, Asian, Hispanic, and White adults. After establishing content validity and preliminary pilot testing, the MB-HSBI was administered to a national sample of 926 culturally diverse adults. Factor analyses and most of the internal consistency results supported multiple scales and subscales measuring motivators of and barriers to each of the targeted health-smart behavior domains. Scores correlated in expected directions with health self-efficacy and with importance of health-related behavioral goals. Pending further psychometric support of the MB-HSBI, this inventory or selected scales from it may serve as flexible and novel tools for (a) assessing motivators of and barriers to health-smart behaviors in community and clinical health promotion research studies and (b) developing assessment-based, culturally sensitive intervention programs that are customized to address the motivators of and barriers to health-smart behaviors identified in target communities, particularly those communities whose members are mostly racial/ethnic minorities and/or have low family incomes. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Determination of firing times for the stochastic Fitzhugh-Nagumo neuronal model

We present for the first time an analytical approach for determining the time of firing of multicomponent nonlinear stochastic neuronal models. We apply the theory of first exit times for Markov processes to the Fitzhugh-Nagumo system with a constant mean gaussian white noise input, representing stochastic excitation and inhibition. Partial differential equations are obtained for the moments of the time to first spike. The observation that the recovery variable barely changes in the prespike trajectory leads to an accurate one-dimensional approximation. For the moments of the time to reach threshold, this leads to ordinary differential equations that may be easily solved. Several analytical approaches are explored that involve perturbation expansions for large and small values of the noise parameter. For ranges of the parameters appropriate for these asymptotic methods, the perturbation solutions are used to establish the validity of the one-dimensional approximation for both small and large values of the noise parameter. Additional verification is obtained with the excellent agreement between the mean and variance of the firing time found by numerical solution of the differential equations for the one-dimensional approximation and those obtained by simulation of the solutions of the model stochastic differential equations. Such agreement extends to intermediate values of the noise parameter. For the mean time to threshold, we find maxima at small noise values that constitute a form of stochastic resonance. We also investigate the dependence of the mean firing time on the initial values of the voltage and recovery variables when the input current has zero mean.     

Space robotics supporting exploration missions: vision, force control and coordination strategy for crew assistants

Many research activities are being carried out about space exploration missions, in order to strongly improve man’s working conditions in planetary environments. Along this line, this work presents some results obtained within the development of an effective robotic crew assistant. This robot can execute a number of operations, both in a completely autonomous manner (i.e. without requiring human supervision) and in a strict cooperation with the astronauts; thus supporting and helping them in executing operations otherwise very difficult or unfeasible to be accomplished. The developed and then adopted functional and algorithmic control architecture for the considered robot assistant, also including vision and force feedback, is described with some details in the present paper.     

Decisional autonomy of planetary rovers

To achieve the ever increasing demand for science return, planetary exploration rovers require more autonomy to successfully perform their missions. Indeed, the communication delays are such that teleoperation is unrealistic. Although the current rovers (such as MER) demonstrate a limited navigation autonomy, and mostly rely on ground mission planning, the next generation (e.g., NASA Mars Science Laboratory and ESA Exomars) will have to regularly achieve long range autonomous navigation tasks. However, fully autonomous long range navigation in partially known planetary‐like terrains is still an open challenge for robotics. Navigating hundreds of meters without any human intervention requires the robot to be able to build adequate representations of its environment, to plan and execute trajectories according to the kind of terrain traversed, to control its motions, and to localize itself as it moves. All these activities have to be planned, scheduled, and performed according to the rover context, and controlled so that the mission is correctly fulfilled. To achieve these objectives, we have developed a temporal planner and an execution controller, which exhibit plan repair and replanning capabilities. The planner is in charge of producing plans composed of actions for navigation, science activities (moving and operating instruments), communication with Earth and with an orbiter or a lander, while managing resources (power, memory, etc.) and respecting temporal constraints (communication visibility windows, rendezvous, etc.). High level actions also need to be refined and their execution temporally and logically controlled. Finally, in such critical applications, we believe it is important to deploy a component that protects the system against dangerous or even fatal situations resulting from unexpected interactions between subsystems (e.g., move the robot while the robot arm is unstowed) and/or software components (e.g., take and store a picture in a buffer while the previous one is still being processed). In this article we review the aforementioned capabilities, which have been developed, tested, and evaluated on board our rovers (Lama and Dala). After an overview of the architecture design principle adopted, we summarize the perception, localization, and motion generation functions required by autonomous navigation, and their integration and concurrent operation in a global architecture. We then detail the decisional components: a high level temporal planner that produces the robot activity plan on board, and temporal and procedural execution controllers. We show how some failures or execution delays are being taken care of with online local repair, or replanning. © 2007 Wiley Periodicals, Inc.