Pattern Recognition

Pattern recognition is a very wide research field. It involves factors as diverse as sensors, feature extraction, pattern classification, decision fusion, applications and others. The signals processed are commonly one, two or three dimensional, the processing is done in real- time or takes hours and days, some systems look for one narrow object class, others search huge databases for entries with at least a small amount of similarity. No single person can claim expertise across the whole field, which develops rapidly, updates its paradigms and comprehends several philosophical approaches. This book reflects this diversity by presenting a selection of recent developments within the area of pattern recognition and related fields. It covers theoretical advances in classification and feature extraction as well as application-oriented works. Authors of these 25 works present and advocate recent achievements of their research related to the field of pattern recognition

Evaluating and Improving 4D-CT Image Segmentation for Lung Cancer Radiotherapy

Lung cancer is a high-incidence disease with low survival despite surgical advances and concurrent chemo-radiotherapy strategies. Image-guided radiotherapy provides for treatment measures, however, significant challenges exist for imaging, treatment planning, and delivery of radiation due to the influence of respiratory motion. 4D-CT imaging is capable of improving image quality of thoracic target volumes influenced by respiratory motion. 4D-CT-based treatment planning strategies requires highly accurate anatomical segmentation of tumour volumes for radiotherapy treatment plan optimization. Variable segmentation of tumour volumes significantly contributes to uncertainty in radiotherapy planning due to a lack of knowledge regarding the exact shape of the lesion and difficulty in quantifying variability. As image-segmentation is one of the earliest tasks in the radiotherapy process, inherent geometric uncertainties affect subsequent stages, potentially jeopardizing patient outcomes. Thus, this work assesses and suggests strategies for mitigation of segmentation-related geometric uncertainties in 4D-CT-based lung cancer radiotherapy at pre- and post-treatment planning stages

NASA Tech Briefs, December 1990

Topics: New Product Ideas; NASA TU Services; Electronic Components and Circuits; Electronic Systems; Physical Sciences; Materials; Computer Programs; Mechanics; Machinery; Fabrication Technology; Mathematics and Information Sciences; Life Sciences

Towards the Development of an Efficient Integrated 3D Face Recognition System. Enhanced Face Recognition Based on Techniques Relating to Curvature Analysis, Gender Classification and Facial Expressions.

The purpose of this research was to enhance the methods towards the development of an efficient three dimensional face recognition system. More specifically, one of our aims was to investigate how the use of curvature of the diagonal profiles, extracted from 3D facial geometry models can help the neutral face recognition processes. Another aim was to use a gender classifier employed on 3D facial geometry in order to reduce the search space of the database on which facial recognition is performed. 3D facial geometry with facial expression possesses considerable challenges when it comes face recognition as identified by the communities involved in face recognition research. Thus, one aim of this study was to investigate the effects of the curvature-based method in face recognition under expression variations. Another aim was to develop techniques that can discriminate both expression-sensitive and expression-insensitive regions for ii face recognition based on non-neutral face geometry models. In the case of neutral face recognition, we developed a gender classification method using support vector machines based on the measurements of area and volume of selected regions of the face. This method reduced the search range of a database initially for a given image and hence reduces the computational time. Subsequently, in the characterisation of the face images, a minimum feature set of diagonal profiles, which we call T shape profiles, containing diacritic information were determined and extracted to characterise face models. We then used a method based on computing curvatures of selected facial regions to describe this feature set. In addition to the neutral face recognition, to solve the problem arising from data with facial expressions, initially, the curvature-based T shape profiles were employed and investigated for this purpose. For this purpose, the feature sets of the expression-invariant and expression-variant regions were determined respectively and described by geodesic distances and Euclidean distances. By using regression models the correlations between expressions and neutral feature sets were identified. This enabled us to discriminate expression-variant features and there was a gain in face recognition rate. The results of the study have indicated that our proposed curvature-based recognition, 3D gender classification of facial geometry and analysis of facial expressions, was capable of undertaking face recognition using a minimum set of features improving efficiency and computation

Biomedical statistical inference: weighted fourier series approximation in the parameter estimation

Not availabl

Detection, monitoring and management of small water bodies:: A case study of Shahjadpur Thana, Sirajgonj district, Bangladesh

Bangladesh is a low-lying flood prone deltaic plain. Excavations are needed to create raised land for safe flood-free homesteads and water bodies for irrigation, and these result in the creation of doba, pukur, dighi and jola. All of these types of small water bodies are almost equally distributed all over the country, except for the heel, which is a natural, saucer shaped depression. For every eight people there is approximately an acre of small water bodies, which range in size from 25-400 sq.m. (doba), 150-1000 sq.m. (pukur), >750 sq.m. (dighi), >2000 sq.m. (jola) and >1000 sq.m. (heel). These small water bodies are commonly used for drinking, bathing and washing, fisheries and aquaculture, duck raising, irrigation, cattle feeding and washing. Despite the importance of small water bodies to the local economy there is no up to date inventory. For this purpose, in my research I have employed integrated participatory remote sensing, GIS and socio-cultural approaches. Although these have not been used before in Bangladesh, 1 argue that they are ideal for effective resource management and sustainable development planning. This research investigated the historical development of the present spatial distribution and use patterns of SWB using Remote Sensing and GIS. This was at a regional scale in four mouzas of Shahjadpur Thana. The data sources were topographical maps, aerial photographs, satellite images, agricultural census data, in-depth questionnaire, focus group meetings and interviewing key informants. An integrated RS-GIS and social sciences methodology was employed to produce maps of change and overlays of the socio-cultural factors involved. Results show that the doba, pukur and dighi, when these are not obstructed by surrounding vegetation, can be detected easily in high resolution panchromatic CORONA satellite photography, IRS-ID Panchromatic image and aerial photography. Comparatively large pukurs, dighis and all jo las and heels are detected in all other optical sensors and the SIR-C radar imagery. Multi-temporal images are helpful for identifying the different types of small water bodies as well separating those from other seasonal large water bodies and flooded areas. It is hoped that the proposed computer assisted participatory management system, including some locally specific guidelines, may be applicable for the planning of other thanas (total 490) in Bangladesh. The proposed management system will facilitate the integration of local planning with the national level planning process, which has not been possible hitherto

Maine Tidal Power Initiative: Environmental Impact Protocols for Tidal Power

As a result of ongoing climate change, the pressure for the development of new sources of renewable energy has increased. It is extremely likely that climate change is caused by anthropogenic activities. Thus even if dramatic gains are made in energy efficiency; the addition of novel renewable energy sources is critical to reducing fossil fuel emissions. Even current goals for a reduction in the growth of greenhouse gas emissions mean that all possible low-carbon or non-carbon emitting energy sources be considered. In the marine environment, energy in tidal currents, waves, and thermal structure may be extracted to produce electricity. These energy sources are a critical element in the overall renewable portfolio since, unlike wind and solar energy, both marine thermal and tidal energy are reliable additions to the overall electrical grid. In the case of tidal energy, the contribution of periodic but reliable sources of renewable energy becomes increasingly critical as wind and solar penetration in the grid increase. In a high renewable energy penetration grid, a resource like tidal energy does not provide the same base load capacity as, for example, a nuclear power plant. However, tidal energy can have the effect of reducing the size of either storage or peaking capacity that is required for grid stability by providing power for recovery of dispatchable loads. However, as an immature technology, significant questions remain regarding basic questions like the scale of the potential resource, the impact on sediment transport, the effects on fish populations and communities, and the ability to design a system which is acceptable by the people in the associated communities. The objectives of the funded project were to examine tidal power development in Maine from all perspectives: engineering, resource assessment, biological effects, and social dimensions. Resource and environmental research focused on data collection for the Cobscook Bay/Western Passage, possibly the most viable commercial tidal energy site in the US, tidal power sites along with initial evaluation of the suitability of the approach for at least two other tidal development sites in Maine. Concomitantly, alternative energy research is used as a basis of education for a number of graduate and undergraduate students at the University of Maine and Maine Maritime Academy. The Maine Tidal Power Initiative has developed resource and environmental assessment protocols in conjunction with the deployment of a specific marine hydrokinetic device. The protocols are transferrable throughout Maine and the US to evaluate tidal energy resources and better understand the potential impact of this development on the environment. Again, site-specific social science and environmental research focused on the Cobscook Bay/Western Passage area near Eastport Maine. The protocols and methods developed at these sites have also been used to perform initial scoping reviews of locations in Castine Harbor and Wiscasset, Maine that represent a more modest and more typical small scale energy resource. Specific barrier issues which have been addressed for the industry are technologies and protocols for measuring and modeling tidal flows, responses of fishes to those flows, and people interacting in these environments. Measuring tidal flows is critical to the key economic driver for this industry, the size of the potential resource. The second barrier issue is the need for methods for measuring the impact of marine hydrokinetic (MHK) devices on fish. Acoustic methods have been used with ground truth validation from trawls. The protocols developed in this project have already had a significant impact on the approach that has been taken at other sites. Finally the assessment of the human community response to these technologies and impact on community cohesion and participation is perhaps the largest single barrier to the acceptance of the projects. This work also has the potential to be replicated at other sites, although in both the case of the environmental effects and the social response to these projects, details of the species impacted and the economic and social environment are the ultimate determinants of impact and acceptance. The technology focus for most of this work has been the cross-flow turbine developed by Ocean Renewable Power Company. Testing in the University of Maine tow tank has allowed a large design space to be explored for the optimization of the commercial turbine design. The design code developed for the project was validated using this data set. Both the design code and the data will be placed in a public repository. The most important outcome of the turbine design portion of the work is some general design parameters that can be used to assist in the site assessment and for benchmarking of proprietary designs. The design as well as the data is available for resource assessment and design comparisons. The appeal of this turbine design is that the potential exists for a low solidity turbine with lower tip speed ratios, which will have good performance. The low solidity and tip speed ratio is likely to reduce the risk of fish impacts and thus reduce environmental impact and community resistance to these technologies. The need for low carbon energy sources is undeniable. Resistance to large-scale renewable energy development also continues to increase. The overall approach to this project, where the design of the system considers environmental impacts and social acceptance from the initial engineering design stages and continues with an adaptive management scheme, is the only option for addressing energy needs at the scale required

NASA Tech Briefs, November 1990

Topics: New Product Ideas; NASA TU Services; Electronic Components and Circuits; Electronic Systems; Physical Sciences; Materials; Computer Programs; Mechanics; Machinery; Fabrication Technology; Mathematics and Information Sciences

Aerospace medicine and biology: A continuing bibliography with indexes (supplement 326)

This bibliography lists 108 reports, articles and other documents introduced into the NASA Scientific and Technical Information System during July, 1989. Subject coverage includes: aerospace medicine and psychology, life support systems and controlled environments, safety equipment, exobiology and extraterrestrial life, and flight crew behavior and performance

NASA Tech Briefs, April 1992

Topics covered include: New Product Ideas; Electronic Components and Circuits; Electronic Systems; Physical Sciences; Materials; Computer Programs; Mechanics; Machinery; Fabrication Technology; Mathematics and Information Sciences