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.     

Carbon Diffusion in Lanthanum Erbium Carbide Stabilized in the Cubic Fluorite Structure

Lanthanum erbium carbide, La_0.5Er_0.5C₂, a salt-like carbide with a cubic fluorite phase structure, has been produced from ¹³C, allowing carbon diffusion rate to be determined using ¹²C. Carbon in salt-like carbides exhibits significant ionicity, and a high carbon diffusion rate would enable a new class of high temperature fuel cells based on carbon-ion transport. The complete lack of carbon diffusion data for salt-like carbides is the motivation for this work. The carbon diffusion rate in La_0.5Er_0.5C₂ has now been determined to be 2.0 ± 0.8 × 10⁻¹³ cm²/s at 850 °C, increasing to 1.8 ± 0.8 × 10⁻¹¹ cm²/s at 1150 °C, with an activation energy of about 95 kJ/mole. These diffusion rates are too low for a carbon-ion fuel cell, but a number of other salt-like carbides exist. Be₂C, in particular, is a salt-like carbide with an antifluorite structure, and should have higher carbon-ion diffusion than cubic La_0.5Er_0.5C₂ due to the unoccupied octahedral sites in the antifluorite structure, but Be₂C presents special difficulties due to the toxic nature of its hydrolysis products.     

The performance characteristics of a novel multi-electrode electromagnetic flowmeter

The design of a novel multi-electrode electromagnetic flowmeter, which provides nine conventional electromagnetic flowmeters housed in a single body, has been used in adverse flow conditions immediately downstream from a header tank. The results show that careful initial calibration, in accord with the pipeline conditions recommended in international standards, enables errors of under 1% to be achieved. The results show that the two electrode planes closest to the header provide results with the greatest errors. The performance with the electrodes mounted in the vertical plane is generally better than that achieved with the electrodes mounted in the horizontal plane. Pressure measurements together with laser Doppler anemometry (LDA) and particle image velocimetry (PIV) techniques have been used to provide details of the magnitude of the disturbance caused to the flow field by the header and outflow combination.     

The effect of radiopacifiers agents on pH,calcium release,radiopacity, and antimicrobial properties of different calcium hydroxide dressings

The aim of this study was to evaluate the antimicrobial activity, pH level, calcium ion release, and radiopacity of calcium hydroxide pastes associated with three radiopacifying agents (iodoform, zinc oxide, and barium sulfate). For the pH and calcium release tests, 45 acrylic teeth were utilized and immersed in ultrapure water. After 24 h, 72 h, and 7 days the solution was analyzed by using a pH meter and an atomic absorption spectrophotometer. Polyethylene tubes filled with the pastes were used to perform the radiopacity test. For the antimicrobial test, 25 dentin specimens were infected intraorally in order to induce the biofilm colonization and treated with the pastes for 7 days. The Live/Dead technique and a confocal microscope were used to obtain the ratio of live cells. Parametric and nonparametric statistical tests were performed to show differences among the groups (P < 0.05). The pH analysis at 7 days showed significant differences (P < 0.05) among the groups. No differences among the pastes were found in the calcium release test on the 7th day (P > 0.05). The calcium hydroxide/iodoform samples had the highest radiopacity and antimicrobial activity against the biofilm‐infected dentin in comparison to the other pastes (P < 0.05). Calcium hydroxide mixed with 17% iodoform and 35% propylene glycol into a paste had the highest pH, calcium ion release, radiopacity, and the greatest antimicrobial action versus similar samples mixed with BaSO4 or ZnO. Microsc. Res. Tech. 78:620–625, 2015. © 2015 Wiley Periodicals, Inc.     

Preliminary investigation of the effect of roughness in Dynarat simulation

Surface roughness has a significant effect on how loads are transmitted at the contact interface between solid bodies. It causes high local pressures in the contacting roughness peaks, i.e., asperities. Even for a low friction coefficient the surface roughness will still play an important role in the early surface wear. A dynamic ratcheting model (Dynarat) for studying the wear rate of ductile materials in rolling/sliding contact is presented. The material is divided into equal-sized rectangular elements (or ‘bricks’). Each material brick accumulates plastic shear strain when the orthogonal shear stress exceeds the brick's shear yield stress. When the accumulated plastic strain exceeds a critical value, the ductility is exhausted and the material is deemed to have failed. Inclusion of surface roughness and refinement of the near-surface brick size cause earlier failure of bricks very close to the surface. In order to model surface roughness, brick size needs to be reduced to, at most, a few microns. The purpose of this investigation is to study the effect of surface roughness in the Dynarat model by comparing the model prediction with the results from two different rolling sliding wear testing machines. Further development of the model is needed, such as more inclusive representations of microstructural behaviour. In addition to that, the ratcheting equation, which drives the Dynarat model, needs to be improved to cover other rail materials and more loading configurations.     

Reviews

Caspar David Friedrich and the Subject of Landscape

by Joseph Leo Koerner, Reaktion Books, 1990

History and precedent in environmental design

by Amos Rapoport, New York: Plenum Press, 1990

Natural Landscapes of Britain from the air

edited by Nicolas Stephens, Cambridge University Press, 1990,

pp. 288, 140 b/w photographs, £19.50

Images of Prehistory

by Peter Fowler and Mick Sharp, Cambridge University Press, 1990,

ISBN 0-521-35646-6, £19.50

Landscape. Monuments and Society: the prehistory of Cranborne Chase

by John Barrett, Richard Bradley & Martin Green, Cambridge University Press, 1991 ISBN O-521-32128X. £35.00 hb.

The Spectacle of Nature

by Nicholas Green, Manchester University Press, 1990

Introduction to Landscape Design

by John L. Motloch, New York: Van Nostrand Reinhold, 1991, 307pp.

Taming the Great South Land: a history of the conquest of nature in Australia,

by William J. lines, Sydney: Allen & Unwin, 1991, pp. xx + 337, 38 plates. Available from UCL Press Ltd., London, £30.00 hb.

River Projects and Conservation: a manual for holistic appraisal.

edited by John L Gardiner, Chichester: John Wiley, 1991, ISBN 0-471-92643-4, 236 pp £50.00 hb

Imagined Country

by John Rennie Short, London and New York: Routledge, 1991

Living in a New Country: history, travelling and language,

by Paul Carter, London: Faber & Faber, 1992. x + 214 pp.

ISBN 0-571-16329-7, $22.95 Hb.

The Aesthetics of Environment

by Arnold Berleant, Philadelphia: Temple University Press, 1992,

ISBN 0-87722-993-7, 240 pp., $34.95.

The English Rural Community

edited by Brian Short. Cambridge:Carnbridge University Press, 1992,

Hb 0-521-40537-8 £35.00 : Pb 0-521-40567-X, £12.95, 239pp.

Fields of Vision: landscape imagery and national identity in England and the United States

by Stephen Daniels, Oxford: Polity Press, 1993, pp.xii + 255,

ISBN 0-7456-0450-1, £39.50,

The Palladian Landscape

by Denis Cosgrove, London: Leicester University Press, 1993, pp. xv + 270.

Nature Pictorialised: “the view' in landscape history

by Gina Crandell, Baltimore: John Hopkins Univ. Press, 1993, pp.196,

ISBN 0-8018-4397-9

edited by David Seamon, Albany: State University of New York Press, 1993, pp. xviii + 363, ISBN 0-7914-1277-6, $19.95 pb, $59.50 hb

Restoring Period Gardens: from the Middle Ages to Georgian times.

by John Harvey, Princes Risborough: Shire, Second edition, 1993,

pp.112, ISBN 0-7478-0200-9, £4.99 pb.

Empty Meeting Grounds: the tourist papers

by Dean McCannell, London: Routledge, 1992,

Dwelling, Seeing, and Designing: toward a phenomenological ecology

346pp, ISBN 0-415-05693-4.

Towards a new landscape

Bernard Jacobson Gallery, 14A Clifford Street, London, W1X 1RF, 1993,

pp.128, ISBN 1-872784-12-7

Place in Space: Human Culture in Landscape

edited by Hana Svobodova & Jan Uhde, Wageningen: Pudoc Scientific, 1993, pp. 128, ISBN 90-220-1089-9, $56.00.     

Linking entrepreneurial orientation to project success

Entrepreneurial orientation (EO) is a strategic posture of an organization, and it is related to basic policies and practices for the development of entrepreneurial actions looking for creating competitive advantages. This study develops and tests a model of the relationship between entrepreneurial orientation and project success in Brazilian context. As quantitative research, a survey was used to collect data. A sample of 100 valid answers from project practitioners was treated through the structural equation modeling method. As research implications, the main result points out the positive correlation between the entrepreneurial orientation and the project success, contributing to the development of this research subject and helping to minimize the gap in the literature that addresses the relationship between project success and EO. In practical terms, understanding that innovativeness, risk taking, proactiveness, autonomy and competitive aggressiveness (the dimensions of the EO) can contribute to project success and can also indirectly impact on organizational performance, could help organizations get competitive advantage when developing correlate factors. Finally, the results suggest that practices of project management can be aligned to the firm's entrepreneurial orientation to enable firms to attain better results in their projects and generate a competitive advantage. On other hand, given the proportion of the impact of EO on project success (20.3%) identified in this study, it is critical that project management professionals expand their horizon to recognize other factors that affect project success.     

Optimal placement of controllers for seismic structures

Active control devices can be implemented on seismic structures to reduce structural response from earthquakes. Certain locations of the structure are advantageous for placement of the controllers in the sense that these locations effectively reduce structural response while using the minimum control effort. A method is proposed which uses an empirical procedure to find the optimal locations by maximizing an optimal locations index. The method takes into consideration the modal responses and earthquake spectra for two different earthquake records. The proposed method is compared to two methods; in the first method a control energy performance index is minimized; the second method uses a minimum response performance index as the criterion. The proposed method is found to agree with the two alternative methods and saves computation time.     

Fissure formation and subsurface subsidence in a coalbed fire

Coalbed fires are uncontrolled subsurface fires that occur around the world. These fires are believed to be significant contributors to annual CO₂ emissions. Although many of these fires have been burning for decades, researchers have only recently begun to investigate physical mechanisms that control fire behavior. One aspect of fire behavior that is poorly characterized is the relationship between subsurface combustion and surface fissures. At the surface above many fires, long, wide fissures are observed. At a coalbed fire near Durango, Colorado, these fissures form systematic orthogonal patterns that align with regional joints in the Upper Cretaceous Fruitland Formation. Understanding the mechanisms that form these fissures is important, as the fissures are believed to play vital roles in sustaining the combustion in the subsurface. In some of the coalbed fire simulation models available today, these fissures are treated as fixed boundary conditions. We argue, using data collected, field observations and simulation result, that there exists a relationship between the location and magnitude of subsidence caused by the fire and the opening of fissures. The results presented suggest that fissures are believed to open when subsurface subsidence gives rise to tensile stresses around pre-existing joints.