Full vectorial simulation for characterizing loss or gain in optical devices with an accurate and automated finite-element program

An efficient, accurate, and automated vectorial finite-element method is described to characterize arbitrarily shaped optical devices having loss or gain properties. The method can be easily implemented inside the pde 2 d software environment, where an interactive session allows the user to specify the problem in a easy-to-use format. For the method to be validated, modal dispersion characteristics of high loss metal-coated optical fibers that have recently been used in applications in scanning near-field optical microscopy are presented and compared with results obtained with two vectorial approaches, i.e., the field expansion and the multiple-multipole methods. These results clearly illustrate the flexibility, accuracy, and ease of implementation of the method.     

Nondestructive Evaluation of <Emphasis Type="Italic">Corymbia citriodora</Emphasis> Logs by Means of the Free Transverse Vibration Test

The bending modulus of elasticity has been used as a wood quality predictor due to the good correlation between bending stiffness and strength. In recent years, there has been an increasing use of nondestructive testing techniques based on dynamic tests to assess wood quality. The objective of this study is to evaluate the results obtained with the application of transverse vibration test to measure the bending modulus of elasticity of Corymbia citriodora logs. The approach used estimated the log cylinders with the diameter equal to the diameter measured at half-length. A sample of 38 C. citriodora logs was tested in free transverse vibration and static bending tests, their diameter measured at half-length ranged from 13.6 to 20 cm and the length ranged between 4 and 4.4 m. A strong correlation (\(\hbox {R}^{2} = 0.92\)) was found between static and dynamic bending modulus of elasticity. The transverse vibration test was faster than the static bending test. The results indicate that the free transverse vibration test provides accurate measurements of bending modulus of elasticity of C. citriodora logs.     

Simple 3,6-bis(diphenylaminyl)carbazole molecular glasses as hole transporting materials for hybrid perovskite solar cells

3,6-bis(diphenylaminyl)carbazole molecular glasses were initially designed as solid hole conductor for solid-state dye-sensitized solar cells. Herein we employed these simple and easy-to-synthesize carbazole derivatives in CH₃NH₃PbI₃ regular perovskite solar cells. Devices using these hole transporting materials (HTM) gave comparable efficiency to the conventional Spiro-OMeTAD based control device made under the same conditions, thus demonstrating the huge potential of carbazole-based molecular glasses as an emerging class of lower cost organic hole conductors with easier synthetic pathways for solid state hybrid solar cells.     

Gender, temperament, and the clinical picture in dysphoric mixed mania: findings from a French national study (EPIMAN)

BACKGROUND: This research derives from the French national multisite collaborative study on the clinical epidemiology of mania (EPIMAN). Our aim is to establish the validity of dysphoric mania along a "spectrum of mixity" extending into mixed mania with subthreshold depressive manifestations; to demonstrate the feasibility of obtaining clinically meaningful data on this entity on a national level; and to characterize the contribution of temperamental attributes and gender in its origin. METHODS: EPIMAN involves training 23 French psychiatrists in four different sites, representing four regions of France; to rigorously apply a common protocol deriving from the criteria of DSM-IV and McElroy et al.; the use of such instruments as the Beigel-Murphy, Ahearn-Carroll, modified HAM-D; and measures of affective temperaments based on the Akiskal-Mallya criteria; obtaining data on comorbidity, and family history (according to Winokur's approach as incorporated into the FH-RDC); and prospective follow-up for at least 12 months. The present report concerns the clinical and temperamental features of 104 manic patients during the acute hospital phase. RESULTS: Dysphoric mania (DM defined conservatively with fullblown depressive admixtures of five or more symptoms) occurred in 6.7%; the rate of dysphoric mania defined broadly (DM, presence of > or = 2 depressive symptoms) was 37%. Depressed mood and suicidal thoughts had the best positive predictive values for mixed mania. In comparison to pure mania (0-1 depressive symptoms), DM was characterized by female over-representation; lower frequency of such typical manic symptomatology as elation, grandiosity, and excessive involvement; higher prevalence of associated psychotic features; higher rate of mixed states in first episodes; and complex temperamental dysregulation along primarily depressive, but also cyclothymic, and irritable dimensions; such irritability was particularly apparent in mixed mania at the lowest threshold of depressive admixtures of two symptoms only. LIMITATION: In a study involving hospitalized affectively unstable psychotic patients, it was difficult to assure that psychiatrists making the clinical diagnoses would be blind to the temperamental measures. However, bias was minimized by the systematic and/or semi-structured nature of all evaluations. CONCLUSIONS: Mixed mania, defined cross-sectionally by the simultaneous presence of at least two depressive symptoms, represents a prevalent and clinically distinct form of mania. Subthreshold depressive admixtures with mania actually appear to represent the more common expression of dysphoric mania. Moreover, an irritable dimension appears to be relevant to the definition of the expression of mixed mania with the lowest threshold of depressive symptoms. Neither an extreme, nor an endstage of mania, "mixity" is best conceptualized as intrusion of mania into its "opposite" temperament - especially that defined by lifelong depressive traits - and favored by female gender. These data suggest that reversal from a temperament to an episode of "opposite" polarity represents a fundamental aspect of the dysregulation that characterizes bipolar disorder. In both men and women with hyperthymic temperament, there appears "protection" against depressive symptom formation during a manic episode which, accordingly, remains relatively "pure". Because men have higher rates of this temperament, pure mania is overrepresented in men; on the other hand, the depressive temperament in manic women seems to be a clinical marker for the well-known female tendency for depression, hence the higher prevalence of mixed mania in women.     

System of Information Systems to support learners (a case study at the University of Technology of Compiègne)

ABSTRACT

Working with Information and Communications Technologies (ICT) is challenging, especially for learners, as ICT control most of their work environment. These learners need to be supported with solutions that are up-to-date with the technological challenges, and can keep up with the fast-paced evolving ICT. Acquiring new knowledge is important for the progress of learners, but it is getting harder to obtain with the overwhelming amount of resources produced by many Information Systems (ISs) in the learning environment. In order to help learners manage resources, we are following the approach of System of Information Systems (SoIS) to support learners. The SoIS gives the opportunity to explore how individual and organisational learning can be enhanced through a combination of different ISs in the learning environment. In this context, we look into the orchestration of SoIS that can provide the ability to index, share, annotate, and recommend important resources in the learning environment. In that sense, this paper presents the approach of SoIS to support learners with a case study at the University of Technology of Compiègne.     

People counting via multiple views using a fast information fusion approach

Real-time estimates of a crowd size is a central task in civilian surveillance. In this paper we present a novel system counting people in a crowd scene with overlapping cameras. This system fuses all single view foreground information to localize each person present on the scene. The purpose of our fusion strategy is to use the foreground pixels of each single views to improve real-time objects association between each camera of the network. The foreground pixels are obtained by using an algorithm based on codebook. In this work, we aggregate the resulting silhouettes over cameras network, and compute a planar homography projection of each camera’s visual hull into ground plane. The visual hull is obtained by finding the convex hull of the foreground pixels. After the projection into the ground plane, we fuse the obtained polygons by using the geometric properties of the scene and on the quality of each camera detection. We also suggest a region-based approach tracking strategy which keeps track of people movements and of their identities along time, also enabling tolerance to occasional misdetections. This tracking strategy is implemented on the result of the views fusion and allows to estimate the crowd size dependently on each frame. Assessment of experiments using public datasets proposed for the evaluation of counting people system demonstrates the performance of our fusion approach. These results prove that the fusion strategy can run in real-time and is efficient for making data association. We also prove that the combination of our fusion approach and the proposed tracking improve the people counting.

     

Usability evaluation of navigation tasks by people with intellectual disabilities: a Google and SAPO comparative study regarding different interaction modalities

Universal Access in the Information Society - This paper presents a case study regarding the usability evaluation of navigation tasks by people with intellectual disabilities. The aim was to...     

GPU Ray Tracing using Irregular Grids

We present a spatial index structure to accelerate ray tracing on GPUs. It is a flat, non‐hierarchical spatial subdivision of the scene into axis aligned cells of varying size. In order to construct it, we first nest an octree into each cell of a uniform grid. We then apply two optimization passes to increase ray traversal performance: First, we reduce the expected cost for ray traversal by merging cells together. This adapts the structure to complex primitive distributions, solving the “teapot in a stadium” problem. Second, we decouple the cell boundaries used during traversal for rays entering and exiting a given cell. This allows us to extend the exiting boundaries over adjacent cells that are either empty or do not contain additional primitives. Now, exiting rays can skip empty space and avoid repeating intersection tests. Finally, we demonstrate that in addition to the fast ray traversal performance, the structure can be rebuilt efficiently in parallel, allowing for ray tracing dynamic scenes.     

A semi-automatic annotation tool for unobtrusive gesture analysis

In a variety of research fields, including linguistics, human–computer interaction research, psychology, sociology and behavioral studies, there is a growing interest in the role of gestural behavior related to speech and other modalities. The analysis of multimodal communication requires high-quality video data and detailed annotation of the different semiotic resources under scrutiny. In the majority of cases, the annotation of hand position, hand motion, gesture type, etc. is done manually, which is a time-consuming enterprise requiring multiple annotators and substantial resources. In this paper we present a semi-automatic alternative, in which the focus lies on minimizing the manual workload while guaranteeing highly accurate annotations. First, we discuss our approach, which consists of several processing steps such as identifying the hands in images, calculating motion of the hands, segmenting the recording in gesture and non-gesture events, etc. Second, we validate our approach against existing corpora in terms of accuracy and usefulness. The proposed approach is designed to provide annotations according to the McNeill (Hand and mind: what gestures reveal about thought, University of Chicago Press, Chicago, 1992) gesture space and the output is compatible with annotation tools such as ELAN or ANVIL.