Research in interactive scene analysis

An interactive scene interpretation system (ISIS) was developed as a tool for constructing and experimenting with man-machine and automatic scene analysis methods tailored for particular image domains. A recently developed region analysis subsystem based on the paradigm of Brice and Fennema is described. Using this subsystem a series of experiments was conducted to determine good criteria for initially partitioning a scene into atomic regions and for merging these regions into a final partition of the scene along object boundaries. Semantic (problem-dependent) knowledge is essential for complete, correct partitions of complex real-world scenes. An interactive approach to semantic scene segmentation was developed and demonstrated on both landscape and indoor scenes. This approach provides a reasonable methodology for segmenting scenes that cannot be processed completely automatically, and is a promising basis for a future automatic system. A program is described that can automatically generate strategies for finding specific objects in a scene based on manually designated pictorial examples

Present state of global wetland extent and wetland methane modelling: methodology of a model inter-comparison project (WETCHIMP)

The Wetland and Wetland CH4 Intercomparison of Models Project (WETCHIMP) was created to evaluate our present ability to simulate large-scale wetland characteristics and corresponding methane (CH4) emissions. A multi-model comparison is essential to evaluate the key uncertainties in the mechanisms and parameters leading to methane emissions. Ten modelling groups joined WETCHIMP to run eight global and two regional models with a common experimental protocol using the same climate and atmospheric carbon dioxide (CO2) forcing datasets. We reported the main conclusions from the intercomparison effort in a companion paper (Melton et al., 2013). Here we provide technical details for the six experiments, which included an equilibrium, a transient, and an optimized run plus three sensitivity experiments (temperature, precipitation, and atmospheric CO2 concentration). The diversity of approaches used by the models is summarized through a series of conceptual figures, and is used to evaluate the wide range of wetland extent and CH4 fluxes predicted by the models in the equilibrium run. We discuss relationships among the various approaches and patterns in consistencies of these model predictions. Within this group of models, there are three broad classes of methods used to estimate wetland extent: prescribed based on wetland distribution maps, prognostic relationships between hydrological states based on satellite observations, and explicit hydrological mass balances. A larger variety of approaches was used to estimate the net CH4 fluxes from wetland systems. Even though modelling of wetland extent and CH4 emissions has progressed significantly over recent decades, large uncertainties still exist when estimating CH4 emissions: there is little consensus on model structure or complexity due to knowledge gaps, different aims of the models, and the range of temporal and spatial resolutions of the models

RICIS Symposium 1992: Mission and Safety Critical Systems Research and Applications

This conference deals with computer systems which control systems whose failure to operate correctly could produce the loss of life and or property, mission and safety critical systems. Topics covered are: the work of standards groups, computer systems design and architecture, software reliability, process control systems, knowledge based expert systems, and computer and telecommunication protocols

Satellite Networks: Architectures, Applications, and Technologies

Since global satellite networks are moving to the forefront in enhancing the national and global information infrastructures due to communication satellites' unique networking characteristics, a workshop was organized to assess the progress made to date and chart the future. This workshop provided the forum to assess the current state-of-the-art, identify key issues, and highlight the emerging trends in the next-generation architectures, data protocol development, communication interoperability, and applications. Presentations on overview, state-of-the-art in research, development, deployment and applications and future trends on satellite networks are assembled

Privacy-preserving efficient searchable encryption

Data storage and computation outsourcing to third-party managed data centers, in environments such as Cloud Computing, is increasingly being adopted by individuals, organizations, and governments. However, as cloud-based outsourcing models expand to society-critical data and services, the lack of effective and independent control over security and privacy conditions in such settings presents significant challenges. An interesting solution to these issues is to perform computations on encrypted data, directly in the outsourcing servers. Such an approach benefits from not requiring major data transfers and decryptions, increasing performance and scalability of operations. Searching operations, an important application case when cloud-backed repositories increase in number and size, are good examples where security, efficiency, and precision are relevant requisites. Yet existing proposals for searching encrypted data are still limited from multiple perspectives, including usability, query expressiveness, and client-side performance and scalability. This thesis focuses on the design and evaluation of mechanisms for searching encrypted data with improved efficiency, scalability, and usability. There are two particular concerns addressed in the thesis: on one hand, the thesis aims at supporting multiple media formats, especially text, images, and multimodal data (i.e. data with multiple media formats simultaneously); on the other hand the thesis addresses client-side overhead, and how it can be minimized in order to support client applications executing in both high-performance desktop devices and resource-constrained mobile devices. From the research performed to address these issues, three core contributions were developed and are presented in the thesis: (i) CloudCryptoSearch, a middleware system for storing and searching text documents with privacy guarantees, while supporting multiple modes of deployment (user device, local proxy, or computational cloud) and exploring different tradeoffs between security, usability, and performance; (ii) a novel framework for efficiently searching encrypted images based on IES-CBIR, an Image Encryption Scheme with Content-Based Image Retrieval properties that we also propose and evaluate; (iii) MIE, a Multimodal Indexable Encryption distributed middleware that allows storing, sharing, and searching encrypted multimodal data while minimizing client-side overhead and supporting both desktop and mobile devices

NASA Tech Briefs, December 1989

Topics include: Electronic Components and Circuits. Electronic Systems, Physical Sciences, Materials, Computer Programs, Mechanics, Machinery, Fabrication Technology, Mathematics and Information Sciences, and Life Sciences

The Design and evaluation of the specification framework for user interface design

This thesis presentsthe design and evaluation of an interface specification meta-language(ISML) that has been developed to explicitly support metaphor abstractions in a model-based, user interface design framework. The application of metaphor to user interface design is widely accepted within the HCI community, yet despite this, there exists relatively little formal support for user interface design practitioners. With the increasing range and power of user interface technologies made widely available comes the opportunity for the designof sophisticated, new forms of interactive environments. The inter-disciplinary nature of HCI offers many approaches to user interface design that include views on tasks, presentationand dialogue architectures and various domain models. Notations and tools that support these views vary equally, ranging from craft-based approachesthrough to computational or tool- based support and formal methods. Work in these areas depicts gradual cohesion of a number of these design views, but do not currently explicitly specify the application of metaphorical concepts in graphical user interface design. Towards addressing this omission, ISML was developed based on (and extending) some existing model- based user interface design concepts. Abstractions of metaphor and other interface design views are captured in the ISML framework using the extensible mark-up language(XML). A six-month case study, developing the `Urban Shout Cast' application is used to evaluate ISML. Two groups of four software engineers developed a networked, multi-user, virtual radio-broadcasting environment. A qualitative analysis examines both how each group developed metaphor designs within the ISML framework and also their perceptions of its utility and practicality. Subsequent analysis on the specification data from both groups reveals aspects of the project's design that ISML captured and those that were missed. Finally, the extent to which ISML can currently abstract the metaphors used in the case study is assessed through the development of a unified `meta-object' model. The results of the case study show that ISML is capable of expressing many of the features of each group's metaphor design, as well as highlighting important design considerations during development. Furthermore, it has been shown, in principle, how an underlying metaphor abstraction can be mapped to two different implementations. Evaluation of the case study also includes important design lessons: ISML metaphor models can be both very large and difficult to separate from other design views, some of which are either weakly expressed or unsupported. This suggests that the appropriate mappings between design abstractions cannot always be easily anticipated, and that understanding the use of model-based specifications in user interface design projects remains a challenge to the HCI community

NASA Tech Briefs, January 1990

Topics include: Electronic Components and Circuits. Electronic Systems, Physical Sciences, Materials, Computer Programs, Mechanics, Machinery, Fabrication Technology, Mathematics and Information Sciences, and Life Science

NASA Tech Briefs, January 1999

Topics include: special coverage sections on sensors and data acquisition and sections on electronic components and circuits, electronic software, materials, mechanics, bio-medical physical sciences, book and reports, and a special section of Photonics Tech Briefs