52 resultados para chaotic and diffusive motion


Relevância:

100.00% 100.00%

Publicador:

Resumo:

In this chapter we described a novel framework for automatic face recognition in the presence of varying illumination, primarily applicable to matching face sets or sequences. The framework is based on simple image processing filters that compete with unprocessed greyscale input to yield a single matching score between individuals. By performing all numerically consuming computation offline, our method both (i) retains the matching efficiency of simple image filters, but (ii) with a greatly increased robustness, as all online processing is performed in closed-form. Evaluated on a large, real-world data corpus, the proposed framework was shown to be successful in video-based recognition across a wide range of illumination, pose and face motion pattern changes

Relevância:

100.00% 100.00%

Publicador:

Resumo:

In spite of over two decades of intense research, illumination and pose invariance remain prohibitively challenging aspects of face recognition for most practical applications. The objective of this work is to recognize faces using video sequences both for training and recognition input, in a realistic, unconstrained setup in which lighting, pose and user motion pattern have a wide variability and face images are of low resolution. In particular there are three areas of novelty: (i) we show how a photometric model of image formation can be combined with a statistical model of generic face appearance variation, learnt offline, to generalize in the presence of extreme illumination changes; (ii) we use the smoothness of geodesically local appearance manifold structure and a robust same-identity likelihood to achieve invariance to unseen head poses; and (iii) we introduce an accurate video sequence “reillumination” algorithm to achieve robustness to face motion patterns in video. We describe a fully automatic recognition system based on the proposed method and an extensive evaluation on 171 individuals and over 1300 video sequences with extreme illumination, pose and head motion variation. On this challenging data set our system consistently demonstrated a nearly perfect recognition rate (over 99.7%), significantly outperforming state-of-the-art commercial software and methods from the literature

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Illumination invariance remains the most researched, yet the most challenging aspect of automatic face recognition. In this paper we propose a novel, general recognition framework for efficient matching of individual face images, sets or sequences. The framework is based on simple image processing filters that compete with unprocessed greyscale input to yield a single matching score between individuals. It is shown how the discrepancy between illumination conditions between novel input and the training data set can be estimated and used to weigh the contribution of two competing representations. We describe an extensive empirical evaluation of the proposed method on 171 individuals and over 1300 video sequences with extreme illumination, pose and head motion variation. On this challenging data set our algorithm consistently demonstrated a dramatic performance improvement over traditional filtering approaches. We demonstrate a reduction of 50-75% in recognition error rates, the best performing method-filter combination correctly recognizing 96% of the individuals.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The objective of this work is to recognize faces using video sequences both for training and novel input, in a realistic, unconstrained setup in which lighting, pose and user motion pattern have a wide variability and face images are of low resolution. There are three major areas of novelty: (i) illumination generalization is achieved by combining coarse histogram correction with fine illumination manifold-based normalization; (ii) pose robustness is achieved by decomposing each appearance manifold into semantic Gaussian pose clusters, comparing the corresponding clusters and fusing the results using an RBF network; (iii) a fully automatic recognition system based on the proposed method is described and extensively evaluated on 600 head motion video sequences with extreme illumination, pose and motion pattern variation. On this challenging data set our system consistently demonstrated a very high recognition rate (95% on average), significantly outperforming state-of-the-art methods from the literature.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The aim of this paper is to provide a washout filter that can accurately produce vehicle motions in the simulator platform at high fidelity, within the simulators physical limitations. This is to present the driver with a realistic virtual driving experience to minimize the human sensation error between the real driving and simulated driving situation. To successfully achieve this goal, an adaptive washout filter based on fuzzy logic online tuning is proposed to overcome the shortcomings of fixed parameters, lack of human perception and conservative motion features in the classical washout filters. The cutoff frequencies of highpass, low-pass filters are tuned according to the displacement information of platform, workspace limitation and human sensation in real time based on fuzzy logic system. The fuzzy based scaling method is proposed to let the platform uses the workspace whenever is far from its margins. The proposed motion cueing algorithm is implemented in MATLAB/Simulink software packages and provided results show the capability of this method due to its better performance, improved human sensation and exploiting the platform more efficiently without reaching the motion limitation.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

 Microsoft Kinect sensor was introduced with the XBOX gaming console. It features a simple and portable motion capturing system. Kinect nowadays presents a point of interest in many fields of study and areas of research where its affordable price compared to its capabilities. The Kinect sensor has the capability to capture and track detected 3D objects with accuracy comparable to that captured by state of the art commercial systems. Human safety is considered one of the highest concerns, specially nowadays where the existence of machines and robots is widely used. In this paper we present using the Kinect technology for enhancing the safety of equipment and operations in seven different applications. These applications include 1) positioning of child’s car seat to optimise the child’s position in respected to front and side air-bags; 2) board positioning system to improve the teacher’s arm reach posture; 3) gas station safety to prevent children from accessing the gas pump; 4) indoor pool safety to avoid children access to deep pool area; 5) robot safety emergency stop; 6) Workplace safety; and 7) older adults fall prediction.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

This paper argues that the industrial contexts of re-imagining, or transforming, literary icons deploy the promotional strategies that are associated with what are usually seen as lesser, or purely commercial, genres. Promotional paratexts reveal transformations of content that position audiences to receive them as creative innovations, superior in many senses to their literary precursors due to the distinctive expertise of creative professionals. Analysing Spielberg's film, The Adventures of Tintin (2011), and Andrew Motion's fictional continuation of Stevenson's Treasure Island, it argues that literary fiction and cinematic texts associated with celebrated authors or auteurist producer-directors share branding discourses characteristic of contemporary consumer culture.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

An overview of the design and performance of geosynthetics in composite barrier systems for biopiles used to remediate hydrocarbon-contaminated soil at Casey Station, Antarctica, is presented. Seven instrumented biopiles were constructed over three field seasons. To minimize the risk of hydrocarbon migration to groundwater, composite barrier systems were used (each using different combinations of geosynthetic clay liners (GCLs), high density polyethylene (HDPE) geomembranes (GMB), and geotextiles (GTXs)). One biopile used a co-extruded geomembrane (HDPE with an ethylene vinyl alcohol (EVOH) core). The liner system was subject to a combination of coupled phenomena that could interact and affect the GMB-GCL composite barrier performance. The exposure conditions involved potential freeze-thaw cycling, hydration-desiccation cycles, cation exchange, direct and diffusive exposure to hydrocarbons. The effect of these phenomena was investigated by monitoring GCL and GMB sacrificial coupons. GCL coupons were placed between the main GCL component and the main geomembrane component of the composite liner and GMB coupons placed between the main GMB sheet and the GTX protection layer. Coupons were exhumed from the biopiles each year. The exhumed GCL field moisture content values ranged from 162% to 22%. After three (3) years in the field, GCL coupons that had undergone at least one hydration/desiccation cycle showed no significant change in swell index values or fluid loss values. The measured hydraulic conductivity of exhumed GCL coupons from Biopiles 1 and 2 (3 × 10-11 m s-1) was within the expected range and not significantly different from the values for virgin GCL. GMB coupons exhumed after three years from Biopiles 1 and 2 showed no significant change in oxidative induction time (OIT), melt flow index or tensile properties. Diffusion tests were performed as an index test for establishing the performance of the GMBs as a diffusive barrier to hydrocarbons, with permeation parameters for BTEX contaminants ranging from P g = 0.9-9.2 × 10-13 m2 s-1 for the exhumed GMB (with values depending on the contaminant and GMB). These values were similar to the parameters obtained for virgin GMBs and there was no significant change with field exposure, with GMBs appearing to be performing well.

Relevância:

40.00% 40.00%

Publicador:

Resumo:

In a series of 6 experiments, two hypotheses were tested: that nominal heading perception is determined by the relative motion of images of objects positioned at different depths (R. F. Wang & J. E. Cutting 1999) and that static depth information contributes to this determination. By manipulating static depth information while holding retinal-image motion constant during  simulated self-movement, the authors found that static depth information played a role in determining perceived heading. Some support was also found for the involvement of R. F. Wang and J. E. Cutting’s (1999) categories of object-image relative motion in determining perceived heading. However, results suggested an unexpected functional dominance of information about heading relative to apparently near objects.

Relevância:

40.00% 40.00%

Publicador:

Resumo:

Objectives
To elicit descriptive data about limited joint range of motion (ROM) in subjects with type II or III spinal muscular atrophy (SMA) and to examine the relation between the number of motions with limited range and both age and functional ability.
Design
Descriptive cross-sectional study.
Setting
Neurologic pediatric outpatient clinic at a hospital in Taiwan.
Participants
Twenty-seven subjects with SMA type II (mean age, 9.8±6.5y) and 17 with SMA type III (mean age, 12.2±8.7y).
Intervention
Measurement with transparent goniometers of joint ROM bilaterally of the shoulder, elbow, wrist, hip, knee, and ankle.
Main outcome measures
The proportion of participants with each ROM limitation compared with all participants with the same SMA type, age distribution of the participants with each ROM limitation, mean range loss of each motion limitation, and the contracture index (risk index of joint contracture).
Results
Eighty-nine percent of the participants with SMA type II experienced knee extension limitation. Approximately 50% of the participants with both types of SMA had ankle dorsiflexion limitation. The motions of knee and hip extension and ankle dorsiflexion also had a relatively high contracture index. The number of motions with limited range positively correlated (P<.001) with age and upper-extremity functional grade (the higher the functional grade, the poorer the functional ability) for SMA type II.
Conclusions
We found varying degrees of joint ROM limitation. Certain motions were noted to be high risks for the development of contractures. This risk was higher mostly in younger children.

Relevância:

40.00% 40.00%

Publicador:

Resumo:

Objective: To examine the test–retest reliability and construct validity of cervical active range of motion and isometric neck muscle strength as measured by the Multi Cervical Rehabilitation Unit (Hanoun Medical Inc., Ontario).
Design: A cross-sectional study.
Setting: Institutional practice.
Subjects: Twenty-one patients with neck pain and 25 healthy volunteers.
Methods: After a trial-run session, active range of motion (AROM) was measured in the subsequent two sessions, with 2–3 days in between. During each session, three measurements were taken for each direction (flexion, extension, lateral flexions and rotations). The measurement of isometric strength was after a 15-minute break following completion of the measurement of AROM. Three measurements were made for each of the six directions (flexion, extension, lateral flexions, protraction and retraction). The software of the Multi Cervical Rehabilitation Unit automatically recorded and calculated the maximum AROM and isometric strength.
Results: There was a good to high level of reliability in the measurement of AROM for both groups of subjects, with intraclass correlation coefficients (ICCs) ranging from 0.81 to 0.96. Results also demonstrated very good to excellent reliability in isometric strength measurement (ICCs ranged from 0.92 to 0.99). Moreover, there was a significant difference in isometric neck muscle strength (p = 0.001) and in AROM (p = 0.034) between the two groups.
Conclusions: The Multi Cervical Rehabilitation Unit was found to be reliable and valid for testing the cervical active range of motion and isometric neck muscle strength for both normal and patient subjects.

Relevância:

40.00% 40.00%

Publicador:

Resumo:

The study proposes a method of interpretation, which gives the contemporary singer-actor and director a method of performance analysis considering both the visual and the auditory aspects of vocal performance. The analysis begins with an analysis of the structure, which maps out the key ideas and translates them into main states of mind. The text analysis is followed by an analysis of the musical treatment of the text, also scanning for extra dramatic meaning inherent in vocal line and musical accompaniment. The so isolated dramatic ideas in text and musical structure and content are finally discussed in terms of their physical aspects, using the system of gesture as practiced by actors and singers before, during and beyond the Baroque period. The method is exemplified by the obbligato recitative "In quali eccessi" from Donna Elvira’s scene in the second act of the opera "Don Giovanni" by L. Da Ponte and W. A. Mozart. The musical example includes gestural notation and a table gestural notation symbols.

Relevância:

40.00% 40.00%

Publicador:

Resumo:

This essay focuses on the poet and intellectual Ko Un, a prominent nationalist and critic of successive authoritarian regimes in Korea. Ashis Nandy gleaned insights into colonial India by investigating the lives of individuals who were emblematic of British colonialism. For instance Nandy focused on Rudyard Kipling to explain how colonialism damaged both Indians and the English who were complicit to it. Similarly, I intend to use the life and literary output of Ko Un to glean insights into Korea’s fight for democracy in the context of the onset of modernisation. Through his political activism and writing Ko celebrated the lives of ordinary Koreans, including his one-time prison mate Kim Dae-jung and numerous political activists, workers, and farmers. He linked their struggle for democracy to a much longer quest to preserve what he considered to be the unique and invaluable aspects of the Korean national character.

Relevância:

40.00% 40.00%

Publicador:

Resumo:

This paper presents the design and simulation of a novel passive micromixer. The micromixer consists of two inlet tanks, one mixing channel and two outlet channels. In order to maximise the mixing efficiency, the following considerations are made: (i) The inlet tanks are followed by a series of microchannels, in which the flow is split. The microchannels are arranged in an interdigital manner to maximise the contact area between the two flows. (ii) The microchannels attached to the lower inlet tank have an upward slope while those attached to the upper tank have a downward slope. The higher-density flow is fed to the lower inlet tank and gets an upward velocity before entering the mixing channel. (iii) Two triangular barriers are placed within the mixing channel to impose chaotic advection and perturb the less-mixed flow along the top and bottom surfaces of the channel. (iv) Finally, two outlet channels are incorporated to discard the less-mixed flow. Three-dimensional simulations are carried out to evaluate the performance of the micromixer. Simulations are performed in the absence and presence of the gravitational force to analyse the influence of gravity on the micromixer. Mixing efficiencies of greater than 92% are achieved using water and a 1011'density biological solvent as the mixing fluids.