12 research outputs found
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User-centred video abstraction
This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University LondonThe rapid growth of digital video content in recent years has imposed the need for the development of technologies with the capability to produce condensed but semantically rich versions of the input video stream in an effective manner. Consequently, the topic of Video Summarisation is becoming increasingly popular in multimedia community and numerous video abstraction approaches have been proposed accordingly. These recommended techniques can be divided into two major categories of automatic and semi-automatic in accordance with the required level of human intervention in summarisation process. The fully-automated methods mainly adopt the low-level visual, aural and textual features alongside the mathematical and statistical algorithms in furtherance to extract the most significant segments of original video. However, the effectiveness of this type of techniques is restricted by a number of factors such as domain-dependency, computational expenses and the inability to understand the semantics of videos from low-level features. The second category of techniques however, attempts to alleviate the quality of summaries by involving humans in the abstraction process to bridge the semantic gap. Nonetheless, a single user’s subjectivity and other external contributing factors such as distraction will potentially deteriorate the performance of this group of approaches. Accordingly, in this thesis we have focused on the development of three user-centred effective video summarisation techniques that could be applied to different video categories and generate satisfactory results. According to our first proposed approach, a novel mechanism for a user-centred video summarisation has been presented for the scenarios in which multiple actors are employed in the video summarisation process in order to minimise the negative effects of sole user adoption. Based on our recommended algorithm, the video frames were initially scored by a group of video annotators ‘on the fly’. This was followed by averaging these assigned scores in order to generate a singular saliency score for each video frame and, finally, the highest scored video frames alongside the corresponding audio and textual contents were extracted to be included into the final summary. The effectiveness of our approach has been assessed by comparing the video summaries generated based on our approach against the results obtained from three existing automatic summarisation tools that adopt different modalities for abstraction purposes. The experimental results indicated that our proposed method is capable of delivering remarkable outcomes in terms of Overall Satisfaction and Precision with an acceptable Recall rate, indicating the usefulness of involving user input in the video summarisation process. In an attempt to provide a better user experience, we have proposed our personalised video summarisation method with an ability to customise the generated summaries in accordance with the viewers’ preferences. Accordingly, the end-user’s priority levels towards different video scenes were captured and utilised for updating the average scores previously assigned by the video annotators. Finally, our earlier proposed summarisation method was adopted to extract the most significant audio-visual content of the video. Experimental results indicated the capability of this approach to deliver superior outcomes compared with our previously proposed method and the three other automatic summarisation tools. Finally, we have attempted to reduce the required level of audience involvement for personalisation purposes by proposing a new method for producing personalised video summaries. Accordingly, SIFT visual features were adopted to identify the video scenes’ semantic categories. Fusing this retrieved data with pre-built users’ profiles, personalised video abstracts can be created. Experimental results showed the effectiveness of this method in delivering superior outcomes comparing to our previously recommended algorithm and the three other automatic summarisation techniques
Developmental and psychometric properties of a belief-based reproductive health behavior questionnaire for female adolescents
Background: The aim of this study was to develop and evaluate the psychometric properties of a questionnaire for the measurement of reproductive health among female adolescents in Iran. Methods: This cross-sectional study was conducted among 289 female students aged 12-15 yr in Tehran, Iran from 2015-2016. The participants were selected using multi-stage random cluster sampling. In addition, the Belief-Based Reproductive Health Questionnaire (BBRHQ) was designed using the properties of the Theory of Planned Behavior (TPB). Results: Exploratory factor analysis of 104 items identified a six-factor solution. These factors jointly accounted for 67 of the observed variance of outcome variable. The confirmatory factor analysis indicated a good fit to the data. In addition, the Cronbach�s alpha coefficient showed an excellent internal consistency (alpha=0.92). Conclusion: Belief-Based Reproductive Health Questionnaire (BBRHQ) is a valid and reliable instrument for measurement of reproductive health behaviors of adolescents. © 2018, Iranian Journal of Public Health. All rights reserved
Hydatidosis of the Pelvic Cavity: A Big Masquerade
We report and discuss a case of primary hydatidosis of the pelvic cavity in a woman who presented with severe weight loss and abdominal pain. This unusual presentation was initially considered as a tumor process until surgical exploration and microscopic studies confirmed the diagnosis. The gynecologists should be aware of possibility of primary hydatid cyst of the pelvic cavity and should be considered in the differential diagnosis of cystic pelvic masses, especially in areas where the disease is endemic
An Improved EMD Method Based on Utilizing Certain Inflection Points in the Construction of Envelope Curves
The empirical mode decomposition (EMD) algorithm is widely used as an adaptive time-frequency analysis method to decompose nonlinear and non-stationary signals into sets of intrinsic mode functions (IMFs). In the traditional EMD, the lower and upper envelopes should interpolate the minimum and maximum points of the signal, respectively. In this paper, an improved EMD method is proposed based on the new interpolation points, which are special inflection points (SIPn) of the signal. These points are identified in the signal and its first (n − 1) derivatives and are considered as auxiliary interpolation points in addition to the extrema. Therefore, the upper and lower envelopes should not only pass through the extrema but also these SIPn sets of points. By adding each set of SIPi (i = 1, 2, n) to the interpolation points, the frequency resolution of EMD is improved to a certain extent. The effectiveness of the proposed SIPn-EMD is validated by the decomposition of synthetic and experimental bearing vibration signals
Effect of theory-based intervention to promote physical activity among adolescent girls: a randomized control trial
Background: Physical activity (PA) rates decline among most high school female students, and due to cultural
restrictions, the reduction of physical activity might be exacerbated in female Iranian adolescents.
Objective: To determine the effects of the physical activity education theory-based intervention to promote
activity among adolescent girls.
Methods: This randomized clinical trial was conducted at public high schools in Tehran, Iran, from September
2015 to July 2016 on 578 girls. The subjects were assigned randomly to two groups of experiment and control
(n=289 per group). All participants in the experimental group received an educational program based on a
modified TPB. Measures were assessed before and 6 months after the experiment. The data were analyzed using
SPSS version 23. We used descriptive statistics, multilevel analysis, Likelihood Ratio (LR) test, P-value less than
0.05 were considered statistically significant.
Results: Five hundred and seventy-eight participants with a mean age of 14.26±0.96 years were studied in two
groups of experiment (n=289) and control (n=289). Moreover, adjusted for the baseline values, the mean of the
scores of the knowledge (84.1±13.6), attitude (31.2±13.6), subjective norm (40.4±11.1), behavioral intention
(34.3±14.7), perceived behavioral control (38.4±11.6), perceived parental control (42.9±14.2), behavioral
(42.6±17.1) was significantly higher in the experiment group compared with the control group (p<0.001). Conclusions: The results of this study implicate that theory based educational intervention is considered to be
more effective in improving physical activity in adolescents. This result can be used to increase adolescent’s
health promotion.
Trial registration: The trial was registered at the Iranian Registry of Clinical Trials (IRST) with the
identification number: IRCT2015070623089N2.
Funding: The authors received no financial support for the research from Kermanshah University of Medical
Sciences
The impact of a TPB-based educational intervention on nutritional behaviors in Iranian adolescent Girls: A randomized controlled trial
Nutritional behaviors of adolescent girls are a major health concern. Adolescents are considered main target group for improvement in nutritional behaviors. This study aimed to determine the impact of an educational intervention based on theory of planned behavior (TPB) on nutritional behaviors in Iranian adolescent girls. This randomized controlled trial study was conducted among 12-16 years old high-school girls in Tehran, Iran, from September 2015 to July 2016. The study subjects were selected using multistage random cluster sampling. Then, they were randomly assigned to the intervention (n=289) and control (n=289) groups. The school-based intervention including nutrition education program based on a modified TPB was performed among intervention group. The control group received only school routine education program. Both groups were assessed at baseline, and after 6-months follow-up. The significant improvement in attitude (15.5, 95 CI=14.7 to 19.3), subjective norms (17.5, 95 CI=15.1 to 0.19), perceived behavioral control (16.1, 95 CI=14.8 to 18.5), perceived parental control (13.4 , 95 CI=11.2 to 17.6), behavioral intention (16.4, 95 CI=14.7 to 19.3), and behavior (17.2, 95 CI=13.7 to 20.7) was observed in intervention group compared to control group (p<0.001 for all dimensions). This study evaluates the impact of a school-based intervention, guided by TPB, on nutritional behaviors improvement as well as knowledge of adolescent girls towards those behaviors. TPB-based educational intervention can effectively improve the healthy nutritional behaviors of adolescent girls. © by PSP
User-centred personalised video abstraction approach adopting SIFT features
The rapid growth of digital video content in recent years has imposed the need for the development of technologies with the capability to produce condensed but semantically rich versions of original input video. Consequently, the topic of Video Summarisation is becoming increasingly popular in the multimedia community and numerous video abstraction approaches have been proposed. Creating personalised video summaries remains a challenge, though. Accordingly, in this paper we propose a methodology for generating user-tailored video abstracts. First, video frames are scored by a group of video experts (operators) according to audio, visual and textual content of the video. Later, SIFT visual features are adopted in our proposed approach to identify the video scenes’ semantic categories. Fusing this retrieved data with pre-built users’ profiles will provide a metric to update the previously averaged saliency scores assigned by video experts to each frame in accordance to users’ priorities. In the next stage, the initial averaged scores of the frames are updated based on the end-users’ generated profiles. Eventually, the highest scored video frames alongside the auditory and textual content are inserted into final digest Experimental results showed the effectiveness of this method in delivering superior outcomes comparing to our previously recommended algorithm and the three other automatic summarisation techniques