4,130 research outputs found
Towards binocular active vision in a robot head system
This paper presents the first results of an investigation and pilot study into an active, binocular vision system that combines binocular vergence, object recognition and attention control in a unified framework. The prototype developed is capable of identifying, targeting, verging on and recognizing objects in a highly-cluttered scene without the need for calibration or other knowledge of the camera geometry. This is achieved by implementing all image analysis in a symbolic space without creating explicit pixel-space maps. The system structure is based on the ‘searchlight metaphor’ of biological systems. We present results of a first pilot investigation that yield a maximum vergence error of 6.4 pixels, while seven of nine known objects were recognized in a high-cluttered environment. Finally a “stepping stone” visual search strategy was demonstrated, taking a total of 40 saccades to find two known objects in the workspace, neither of which appeared simultaneously within the Field of View resulting from any individual saccade
Measuring Rights-Based Perspectives: A Validation of the Human Rights Lens in Social Work Scale
Objective: This article reports the initial validation of the Human Rights Lens in Social Work (HRLSW) scale, a tool designed to measure a social worker’s ability to see individual and social problems as resulting from human rights violations. The purpose of the research was to gather evidence regarding the validity of this multidimensional measure of a new construct, i.e., human rights lens. Method: Data from a convenience sample of 1,014 licensed clinical social workers were collected by electronic survey, and the sample was split to conduct discrete exploratory and confirmatory factor analyses. The exploratory factor analysis was performed on half of the sample (n = 507) to establish the underlying factor structure of the construct; the other half of the sample (n = 507) underwent a confirmatory factor analysis to examine the subsample’s psychometric properties. Results: A respecified model using only one error covariance fit the data very well. All fit indices were within their critical values (x2/df ratio = 1.5; CFI =.99; TLI = .99; RMSEA = .03; SRMR = .03). Thus, factor analysis confirms a two-factor, 11-item model for the HRLSW scale, consisting of two subscales, clients seen as experiencing rights violations, and social problems seen as rights violations. Conclusions: This scale is a useful tool for educators, researchers, and practitioners who want to practice—or promote the practice of—social work as a human rights profession
Distortion of the L→M transition in the photocycle of the bacteriorhodopsin mutant D96N: a time-resolved step-scan FTIR investigation
AbstractThe D96N mutant of bacteriorhodopsin has often been taken as a model system to study the M intermediate of the wild type photocycle due to the long life time of the corresponding intermediate of the mutant. Using time-resolved step-scan FTIR spectroscopy in combination with a sample changing wheel we investigated the photocycle of the mutant with microsecond time resolution. Already after several microseconds an intermediate similar to the MN state is observed, which contrasts with the M state of the wild type protein. At reduced hydration M and N intermediates similar to those of wild type BR can be detected. These results have a bearing on the interpretation of the photocycle of this mutant. A mechanism is suggested for the fast rise of MN which provides some insight into the molecular events involved in triggering the opening of the cytosolic channel also of the wild type protein
Azimuth axis optical alignment system Final report
Azimuth axis optical alignment system to monitor and measure attitude or angular position of remote object about azimuth axis using phase information imposed on returning beam of ligh
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