Grid-based method for ranking images with multiple objects

One of the content-based image retrieval techniques is the shape-based technique, which allows users to ask for objects similar in shape to a query object. Sajjanhar and Lu proposed a method for shape representation and similarity measure called the grid-based method [1]. They have shown that the method is effective for the retrieval of segmented objects based on shape. In this paper, we describe a system which uses the grid-based method for retrieval of images with multiple objects. We perform experiments on the prototype system to compare the performance of the grid-based method with the Fourier descriptors method [2]. Preliminary results have been presented.

Study of acoustic emission (AE) caused by high voltage insulators

Acoustic emission (AE) study based on the acoustic signal ranges from 30MHz to 300MHz has been performed to diagnose the deterioration of insulation level in outdoor ceramic insulator. Different weather conditions combining with artificially created pollution were produced in laboratory and measurements were recorded over a fixed period of time. Pollution due to fine dust particles has been created according to IEC standard under wet and dry conditions. Samples that exhibit internal cracks and fracture were used in this study. The collected AE signals were sampled and analysed using fractal theory. The results of this study have clearly demonstrated the prospect of using AE technique to monitor the working condition of outdoor insulator.

Multi-scale analysis of connectivity for image retrieval

Previously, we proposed the concept of connectivity to obtain discriminating shape descriptors. In this paper, we use connectivity to obtain superior distance histograms for multi-scale images. Experiments are performed to evaluate the distance histograms, based on connectivity, for shape-based retrieval of multi-scale images. Item S8 within the MPEG-7 still images content set is used for performing experiments. Experimental results show that the proposed method enhances retrieval performance significantly.

Spherical harmonics descriptor for 2D-image retrieval

In this paper, spherical harmonics are proposed as shape descriptors for 2D images. We introduce the concept of connectivity; 2D images are decomposed using connectivity, which is followed by 3D model construction. Spherical harmonics are obtained for 3D models and used as descriptors for the underlying 2D shapes. Difference between two images is computed as the Euclidean distance between their spherical harmonics descriptors. Experiments are performed to test the effectiveness of spherical harmonics for retrieval of 2D images. Item S8 within the MPEG-7 still images content set is used for performing experiments; this dataset consists of 3621 still images. Experimental results show that the proposed descriptors for 2D images are effective

A composite descriptor for shape retrieval

In this paper, a composite descriptor for shape retrieval has been proposed. The proposed descriptor is obtained from Generic Fourier Descriptors (GFD) for the shape region and the shape contour. A composite descriptor derived from GFD of the shape region and the shape contour is used for indexing and retrieval of shapes. Difference between two images is computed as the Euclidean distance between their composite descriptors. Experiments are performed to test the effectiveness of the proposed descriptor for retrieval of 2d images. Sets of composite descriptors, obtained by assigning different weights to the region component and the contour component, are also evaluated. Item S8 within the MPEG-7 Still Images Content Set is used for performing experiments; this dataset consists of 3621 still images. Experimental results show that the proposed descriptor is effective.

Image semantic classification by using SVM

There exists an enormous gap between low-level visual feature and high-level semantic information, and the accuracy of content-based image classification and retrieval depends greatly on the description of low-level visual features. Taking this into consideration, a novel texture and edge descriptor is proposed in this paper, which can be represented with a histogram. Furthermore, with the incorporation of the color, texture and edge histograms searnlessly, the images are grouped into semantic classes using a support vector machine (SVM). Experiment results show that the combination descriptor is more discriminative than other feature descriptors such as Gabor texture.

Automatic pattern-taxonomy extraction for web mining

In this paper, we propose a model for discovering frequent sequential patterns, phrases, which can be used as profile descriptors of documents. It is indubitable that we can obtain numerous phrases using data mining algorithms. However, it is difficult to use these phrases effectively for answering what users want. Therefore, we present a pattern taxonomy extraction model which performs the task of extracting descriptive frequent sequential patterns by pruning the meaningless ones. The model then is extended and tested by applying it to the information filtering system. The results of the experiment show that pattern-based methods outperform the keyword-based methods. The results also indicate that removal of meaningless patterns not only reduces the cost of computation but also improves the effectiveness of the system.

Special report : the wellbeing of Australians : groups with the highest and lowest wellbeing in Australia

Overview and Aim
1. This report concerns an analysis of the cumulative data from 15 surveys using the Personal Wellbeing Index to measure Subjective Wellbeing. The total number of respondents is about 30,000 but not all data were available for all analyses due to changing variables between
surveys.
2. The aim of this analysis is to determine those sub-groups with the highest and the lowest wellbeing.
Method
3. The definition of sub-groups is through the demographic variables of Income, Gender, Age, Household Composition, Relationship Status and Employment Status. Index domains are also included. While not every combination of demographic variables has been tested, the total number of combinations analysed was 3,277.
4. Extreme group mean scores are defined as lying above 79 points and below 70 points. These values are at least five standard deviations beyond the total sample mean score and are, therefore, extreme outliers. The minimum number of responses that could form such a group is
one. Data are accumulated across surveys for corresponding groups.
Results
5. The initial search for the most extreme groups identified the 20 highest and the 20 lowest groups with a minimum N=10. These are termed the ‘Exclusive’ groups since they were based only on the previously identified extreme scores. In order to determine the true mean of each of these groups, a further analysis incorporated all respondents who met the definition of group membership. For example, an Exclusive group defined as [male, 76+ years] would contain only the accumulation of scores from individual surveys that met the extreme score criterion (<70 or >79). The Inclusive group included the scores from all survey respondents who matched the group definition of male, 76+ years.
6. The results revealed a dominance by the domains of the Personal Wellbeing Index. The extreme high groups were predicted by high scores on all domains except safety and relationships. The low groups were defined by low scores on all seven domains.
7. A further search for extreme groups was undertaken that was restricted to the demographic descriptors. The 20 highest and 20 lowest groups were identified based on a minimum cell content of N=10. The corresponding Inclusive group means were then calculated as before.
8. In order to increase the reliability of the final groups, a minimum cell content of N=20 cases was imposed.
9. Six extreme high groups were identified. These are dominated by high income and the presence of a partner. Five extreme low groups were identified. These are dominated by very low income, the absence of a partner, and unemployment.
Conclusions
10. The conclusions drawn from these analyses are as follows:
10.1 The central defining characteristics of people forming the extreme high wellbeing groups is high household income and living with a partner.
10.2 The central defining risk factors for people forming the extreme low wellbeing groups are very low household income, not living with a partner, and unemployment.
10.3 None of these five demographic characteristics are sufficient to define extreme wellbeing groups on their own. They all act in combinations of at least two risk factors together.

Constructing artificial images of facial expressions

This paper presents a method for construction of artificial images of facial expressions. The proposed fractal-based synthesis procedure called pixel-based correspondence works on 2D images and does not require any depth information. This method can generate artificial images of an object when only a single image is given. Using the proposed method, effective example-based facial analysis systems can be trained and utilised in various applications.

Complementing a region descriptor for shape retrieval

In this paper, we propose to complement a region descriptor for shape retrieval with a contour descriptor; the descriptor thus obtained is a composite descriptor. We use a combination of a region descriptor and contour descriptor to obtain the proposed descriptor. A contour extraction technique is also proposed; it is required for extracting the contour of the image prior to applying a contour descriptor. Normalization of descriptors is required before disparate descriptors can be combined into a single descriptor. Hence, we test the performance of two common methods for normalization of descriptors and adopt the better performing method. Experiments are performed to test the effectiveness of the proposed descriptor for retrieval of 2d images. Sets of composite descriptors, obtained by assigning different weights to the region component and the contour component, are also evaluated. Item S8 within the MPEG-7 Still Images Content Set is used for performing experiments; this dataset consists of 3621 still images. Experimental results show that the proposed descriptor is effective.

Animal movement in dynamic landscapes : interaction between behavioural strategies and resource distributions

Most ecological and evolutionary processes are thought to critically depend on dispersal and individual movement but there is little empirical information on the movement strategies used by animals to find resources. In particular, it is unclear whether behavioural variation exists at all scales, or whether behavioural decisions are primarily made at small spatial scales and thus broad-scale patterns of movement simply reflect underlying resource distributions. We evaluated animal movement responses to variable resource distributions using the grey teal (Anas gracilis) in agricultural and desert landscapes in Australia as a model system. Birds in the two landscapes differed in the fractal dimension of their movement paths, with teal in the desert landscape moving less tortuously overall than their counterparts in the agricultural landscape. However, the most striking result was the high levels of individual variability in movement strategies, with different animals exhibiting different responses to the same resources. Teal in the agricultural basin moved with both high and low tortuosity, while teal in the desert basin primarily moved using low levels of tortuosity. These results call into question the idea that broad-scale movement patterns simply reflect underlying resource distributions, and suggest that movement responses in some animals may be behaviourally complex regardless of the spatial scale over which movement occurs.

Do mass media campaigns capture and describe the experience of stroke symptoms?

Introduction: In 2006, the National Stroke Foundation of Australia launched the FAST (Face, Arm, Speech)/ Signs of Stroke (SOS) (5 symptom categories) campaigns designed to improve public awareness of stroke symptoms and the sense of urgency to present to hospital. However, there is little published review of how well such campaigns capture and describe the experience of stroke. This study aims to examine the awareness, content and language of the FAST/SOS campaigns by those experiencing stroke symptoms.
Methods: Interviews were conducted with either the stroke patient or a witness (incapacitated patients) whilst an inpatient at Box Hill or Maroondah Hospitals between August 2006 through April 2008. They were asked to describe awareness of campaigns, symptoms experienced (recorded verbatim and coded into campaign symptom categories) and to evaluate the descriptions of “Signs of Stroke” against their own experience (exact, somewhat, or not at all).
Results: Of 239 eligible stroke cases, 167 (70%) were interviewed (100 patients and 67 witnesses). Few (n= 20, 12%) were aware of the FAST campaign and only 16% recalled all three symptoms. Most recalled that it was “something” to do with the face, however facial droop (n=6) was less commonly experienced compared to speech impairments (n=16) and arm drift (n=13). FAST symptoms detected 84% (patients 77% and witnesses 94%) and SOS symptoms 100% of stroke patients. Patients not describing a FAST symptom (n=27) described: arm or hand numbness; hand incoordination; leg impairments; vision disturbances; or collapse. Approximately, half of patients and witnesses thought the SOS descriptions of the most commonly detected symptoms (arm/leg/face weakness or paralysis or numbness and speech impairments) exactly described the experience. Common language used to describe symptoms were: incoordination of hands or limbs; sudden difficulty walking; drooped/dropped face or mouth; slurred or loss of speech; pins and needles or tingling.
Conclusion: Both campaigns identified symptoms most commonly detected in those experiencing and reacting to symptoms. Both campaigns could portray symptoms more realistically using common descriptors without impacting on the simplicity of the messages

Iridescent structurally based coloration of eyespots correlates with mating success in the peacock

Gaudy plumage coloration is a widespread ornamental trait in birds and thought to be sexually selected. Although much attention has been devoted to structural coloration reflecting in UV, the signaling function of structural colors lacking UV reflectance and those that exhibit iridescence coloration are poorly documented. The train of the peacock (Pavo cristatus), a classical example of a sexually selected trait, is composed of iridescent structurally colored eyespots not reflecting in UV. Until today, the role played by the structural color of the eyespots in female mate choice has never been investigated using spectrometry. We measured eyespot coloration from a stationary angle (static coloration) and the change in coloration resulting from different angles (iridescent coloration). We assessed coloration with reflectance spectrometry, and we analyzed reflectance spectra using 2 methods. First, we extracted the reflectance spectra shape descriptors hue, brightness, and chroma. Second, we computed color and brightness contrasts signaled by eyespot feathers, taking peafowl color visual sensitivity into account. Iridescence was estimated by the maximal change for all parameters. Brightness was correlated with male mating success. The maximal change in color contrast was correlated with both the frequency of male visitation by females and male mating success. These results suggest that peahens can use both static and dynamic (i.e., iridescent) aspects of plumage structural coloration as signals to detect and choose their mates.

Funding special education provision by means of discriminant function analysis

This thesis is concerned with the development of a funding mechanism, the Student Resource Index, which has been designed to resolve a number of difficulties which emerged following the introduction of integration or inclusion as an alternative means of providing educational support to students with disabilities in the Australian State of Victoria. Prior to 1984, the year in which the major integration or inclusion initiatives were introduced, the great majority of students with disabilities were educated in segregated special schools, however, by 1992 the integration initiatives had been successful in including within regular classes approximately half of the students in receipt of additional educational assistance on the basis of disability. The success of the integration program brought with it a number of administrative and financial problems which were the subject of three government enquiries. Central to these difficulties was the development of a dual system of special education provision. On one hand, additional resources were provided for the students attending segregated special schools by means of weighted student ratios, with one teacher being provided for each six students attending a special school. On the other hand, the requirements of individual students integrated into regular schools were assessed by school-based committees on the basis of their perceived extra educational needs. The major criticism of this dual system of special education funding was that it created inequities in the distribution of resources both between the systems and also within the systems. For example, three students with equivalent needs, one of whom attended a special school and two of whom attended different regular schools could each be funded at substantially differing levels. The solution to these inequities of funding was seen to be in the development of a needs based funding device which encompassed all students in receipt of additional disability related educational support. The Student Resource Index developed in this thesis is a set of behavioural descriptors designed to assess degree of additional educational need across a number of disability domains. These domains include hearing, vision, communication, health, co-ordination (manual and mobility), intellectual capacity and behaviour. The completed Student Resource Index provides a profile of the students’ needs across all of these domains and as such addresses the multiple nature of many disabling conditions. The Student Resource Index was validated in terms of its capacity to predict the ‘known’ membership or the type of special school which some 1200 students in the sample currently attended. The decision to use the existing special school populations as the criterion against which the Student Resource Index was validated was based on the premise that the differing resource levels of these schools had been historically determined by expert opinion, industrial negotiation and reference to other special education systems as the most reliable estimate of the enrolled students’ needs. When discriminant function analysis was applied to some 178 students attending one school for students with mild intellectual disability and one facility for students with moderate to severe intellectual disability the Student Resource Index was successful in predicting the student's known school in 92 percent of cases. An analysis of those students (8 percent) which the Student Resource Index had failed to predict their known school enrolment revealed that 13 students had, for a variety of reasons, been inappropriately placed in these settings. When these students were removed from the sample the predictive accuracy of the Student Resource Index was raised to 96 percent of the sample. By comparison the domains of the Vineland Adaptive Behaviour Scale accurately predicted known enrolments of 76 percent of the sample. By way of replication discriminant function analysis was then applied to the Student Resource Index profiles of 518 students attending Day Special Schools (Mild Intellectual Disability) and 287 students attending Special Developmental Schools (Moderate to Severe Intellectual Disability). In this case, the Student Resource Index profiles were successful in predicting the known enrolments of 85 percent of students. When a third group was added, 147 students attending Day Special Schools for students with physical disabilities, the Student Resource Index predicted known enrolments in 80 percent of cases. The addition of a fourth group of 116 students attending Day Special Schools (Hearing Impaired) to the discriminant analysis led to a small reduction in predictive accuracy from 80 percent to 78 percent of the sample. A final analysis which included students attending a School for the Deaf-Blind, a Hospital School and a Social and Behavioural Unit was successful in predicting known enrolments in 71 percent of the 1114 students in the sample. For reasons which are expanded upon within the thesis it was concluded that the Student Resource Index when used in conjunction with discriminant function analysis was capable of isolating four distinct groups on the basis of their additional educational needs. If the historically determined and varied funding levels provided to these groups, inherent in the cash equivalent of the staffing ratios of Day Special Schools (Mild Intellectual Disability), Special Development Schools (Moderate to Severe Intellectual Disability), Day Special Schools (Physical Disability) and Day Special Schools (Hearing Impairment) are accepted as reasonable reflections of these students’ needs these funding levels can be translated into funding bands. These funding bands can then be applied to students in segregated or inclusive placements. The thesis demonstrates that a new applicant for funding can be introduced into the existing data base and by the use of discriminant function analysis be allocated to one of the four groups. The analysis is in effect saying that this new student’s profile of educational needs has more in common with Group A than with the members of Groups B, C, or D. The student would then be funded at Group A level. It is immaterial from a funding point of view whether the student decides to attend a segregated or inclusive setting. The thesis then examines the impact of the introduction of Student Resource Index based funding upon the current funding of the special schools in one of the major metropolitan regions. Overall, such an initiative would lead to a reduction of 1.54 percent of the total funding accruing to the region’s special schools.

Pixel-based correspondence for facial images

A pixel-based correspondence method is presented for representation of facial images. The proposed method consists of two modules: face-image matching and face-image morphing. In the face-image matching module, the correspondence between two images are calculated for all pixel locations. A novel area-based matching method is proposed that makes use of the concept of the fractal dimension, and develops a non-parametric local transform as a basis for establishing correspondence between two face images. In the face-image morphing module, a mapping is performed for deformation of the source face image onto the target face image. This is done to map the pixels in the source face image to the location of their corresponding pixels in the target image.