Classification of soil‐ and bedrock‐dominated landslides in British Columbia using segmentation of satellite imagery and DEM data

Landsat Enhanced Thematic Mapper Plus (ETM+) and digital elevation model (DEM) data were used in a segmentation and classification procedure to classify slide scars in the northern Cascade Mountains of British Columbia, Canada. The area was stratified into features that were likely candidates for landsliding and those that were not; shape criteria were applied that were used to identify objects as slides; and finally, rules based on shape, texture and neighbouring features were used to separate soil‐dominated slides from bedrock‐dominated slides, an important distinction in mass movement inventories and for applied and theoretical studies. Approximately 65% classification accuracy was obtained. Slopes experiencing multiple failures, which can create less distinct features on the ground, may have contributed to some of the error in classification.     

Geomorphometric processing of digital elevation models

The general system of geomorphometry is composed of elevation, derivatives of elevation at a point, and moments of the distribution of elevation over some area. All of the point measures in this system can be obtained by computer processing of a digital elevation model (DEM), and they can be used as input to the analysis and classification of terrain. A suite of FORTRAN programs implementing this system for dense grid DEMs has been designed and used in various operating environments. Attention has been given to the methods used in the approximation of terrain concepts such as slope and relief. An area of high relief in subarctic Canada is used to illustrate the discussion.     

Parallel simulated annealing using speculative computation

A parallel simulated annealing algorithm that is problem-independent, maintains the serial decision sequence, and obtains speedup which can exceed log₂P on P processors is discussed. The algorithm achieves parallelism by using the concurrency technique of speculative computation. Implementation of the parallel algorithm on a hypercube multiprocessor and application to a task assignment problem are described. The simulated annealing solutions are shown to be, on average, 28% better than the solutions produced by a random task assignment algorithm and 2% better than the solutions produced by a heuristic     

A behaviour instantiation agent architecture

This paper presents a novel agent architecture, the VM-architecture, that chooses its actions via a behaviour instantiation mechanism inspired by Maes?s behaviour networks. The VM-architecture enables an agent, VMattie, built upon it, actively to gather information from humans using email in natural language, to compose announcements of next week?s seminars and to mail them each week to a list that she keeps updated. VMattie does all this without the supervision of a human. Implemented and tested in a UNIX environment, the system?s performance surpassed the authors? fondest hopes.     

A unified systolic array for adaptive beamforming

We present a new algorithm and systolic array for adaptive beamforming. Our approach improves on McWhirter's pioneering work in two respects. First, our algorithm uses only orthogonal transformations and thus should have better numerical properties. Second, the algorithm can be implemented on one single p × p triangular array of programmable processors that offers a throughput of one residual element per cycle.     

Urban Real Estate in Ghana: A Study of Housing-related Remittances from Australia

A combination of rapid population growth and low incomes results in housing shortages in Ghana. Migration to Europe, America and Scandinavia has provided a way for some Ghanaians to escape this housing problem, as they take advantage of salaries there in order to save and build houses much quicker back home. This study of Ghanaian migrants in Sydney shows that by keeping at two or more jobs and saving about 33 per cent of their incomes, they are able to build houses worth US$100 000 in Ghana within 3–6 years. How these Ghanaians acquire land, how they build and their experiences after completing their houses provide clues on how to improve housing policy in Ghana.     

Not just a migration problem: Metapopulations,habitat shifts,and gene flow are also important for fishway science and management

Worldwide, fishways are increasingly criticized for failing to meet conservation goals. We argue that this is largely due to the dominance of diadromous species of the Northern Hemisphere (e.g., Salmonidae) in the research that underpins the concepts and methods of fishway science and management. With highly diverse life histories, swimming abilities and spatial ecologies, most freshwater fish species do not conform to the stereotype imposed by this framework. This is leading to a global proliferation of fishways that are often unsuitable for native species. The vast majority of fish populations do not undertake extensive migrations between clearly separated critical habitats, yet the movement of individuals and the genetic information they carry is critically important for population viability. We briefly review some of the latest advances in spatial ecological modelling for dendritic networks to better define what it means to achieve effective fish passage at a barrier. Through a combination of critical habitat assessment and the modelling of metapopulations, climate change‐driven habitat shifts, and adaptive gene flow, we recommend a conceptual and methodological framework for fishway target‐setting and monitoring suitable for a wide range of species. In the process, we raise a number of issues that should contribute to the ongoing debate about fish passage research and the design and monitoring of fishways.     

The social construction of housing management

Although housing management as an occupational role has existed for over a century it has never received an adequate definition, and its scope and emphasis have varied over time. This paper locates housing management within the debates on the nature of the professions and bureaucracy, and suggests that these analyses are inadequate. It is proposed that a more fruitful approach in understanding the nature of housing management is derived from a consideration of its ‘social construction’. In support of this interpretation material from qualitative empirical research with practitioners is presented and analysed. Key respondents were identified as people working at the boundaries of housing management, such as in a caring or support role, since it was felt that the perceptions of such boundaries were important in defining the limits and limitations of housing management. In conclusion it is suggested that this is a critical moment for housing management in terms of achieving a more rigorous definition of its activities, and of seeking to resolve the conflict between the pressures to organise around commercial objectives and to provide a welfare service. Meanwhile there remains a somewhat paradoxical situation in that whilst the lack of consistent practice within housing management weakens its claims to occupational strength and legitimacy, these same inconsistencies permit individual practitioners the flexibility to offer a more responsive service to those in need.     

An efficient Neuro-Fuzzy approach to nuclear power plant transient identification

Transient identification in nuclear power plants (NPP) is often a computational very hard task and may involve a great amount of human cognition. The early identification of unexpected departures from steady state behavior is an essential step for the operation, control and accident management in NPPs. The bases for the transient identification relay on the evidence that different system faults and anomalies lead to different pattern evolution in the involved process variables. During an abnormal event, the operator must monitor a great amount of information from the instruments that represents a specific type of event. Recently, several works have been developed for transient identification. These works frequently present a non reliable response, using the “don´t know” as the system output. In this work, we investigate the possibility of using a Neuro-Fuzzy modeling tool for efficient transient identification, aiming to helping the operator crew to take decisions relative to the procedure to be followed in situations of accidents/transients at NPPs. The proposed system uses artificial neural networks (ANN) as first level transient diagnostic. After the ANN has done the preliminary transient type identification, a fuzzy-logic system analyzes the results emitting reliability degree of it. A validation of this identification system was made at the three loops Pressurized Water Reactor (PWR) simulator of the Human-System Interface Laboratory (LABIHS) of the Nuclear Engineering Institute (IEN/CNEN/Brazil). The obtained results show the potential of this new transient identification system to be used in an operational NPP in order to assist the operators to take decisions during transients/accidents.