Engineering geology of nearshore areas off Richards Island, N.W.T.: a comparison of stable and actively eroding coastlines

1991 ◽  
Vol 28 (2) ◽  
pp. 179-188 ◽  
Author(s):  
P J Kurfurst ◽  
S. R. Dallimore
Keyword(s):  
Engineering Geology ◽  
Acoustic Properties ◽  
Coastal Processes ◽  
Considerable Variability ◽  
Laboratory Studies ◽  
Coastal Site ◽  
Spatial Sense ◽  
Main Factors ◽  
Landfast Sea Ice ◽  
Ice Content

Nearshore areas off northern Richards Island can be expected to show considerable variability in lithology, strengths, and geothermal setting both in a temporal and a spatial sense. Drilling and laboratory studies carried out along onshore–offshore transects at a stable coastal site and an actively eroding coastal site have identified six major stratigraphic units of Holocene and pre-Holocene (Wisconsinan) age. The main factors controlling the geotechnical properties of these sediments and their distribution are the occurrence of shallow permafrost beneath areas seasonally covered by landfast sea ice, rapid degradation of permafrost in areas farther offshore, ice content of thawing pre-Holocene sediments, and variability in coastal processes. Key words: nearshore deposits, engineering geology, permafrost, physical properties, acoustic properties.

Experimental Study on the Bending Properties of GFRP Middle Beam in Foundation Pit Support

2010 ◽  
Vol 160-162 ◽  
pp. 921-926
Author(s):  
Wei Zhang ◽  
Ming Yi Zhang ◽  
Li Tang Gao
Keyword(s):  
Test Results ◽  
Laboratory Studies ◽  
Bending Properties ◽  
Loading Test ◽  
Foundation Pit ◽  
Local Strength ◽  
Main Factors ◽  
Section Type ◽  
The Stability ◽  
The Web

The laboratory studies on the mechanical properties of the GFRP beams with two different sections are carried out. Their mechanical behavior and the failure features are described and analyzed. The test results indicate that the stability of the GFRP middle beam and the local strength at the joint between the web and the flange are the main factors in the design of the composite middle beams. Based on the test results, a new-style GFRP middle beam with- I-section and double webs is proposed and designed. Loading test shows that the composite material with I-section and double webs can satisfy the requirements for the globe and local stabilities, and simultaneously the material strengths of the middle beam can also be fully utilized. Maybe the proposed new-style beam is the best section type for the middle beam. Also, local strengthening should be adopted in the middle beam-bolt joint.

scholarly journals The accumulative coasts dynamics in enclosed bays of Antarctica (in example the key area of the South Georgia microcontinent)

2019 ◽  
Vol 59 (2) ◽  
pp. 265-270
Author(s):  
N. N. Dunaev ◽  
I. O. Leont’yev
Keyword(s):  
Mathematical Modeling ◽  
Coastal Zone ◽  
Tectonic Subsidence ◽  
Coastal Processes ◽  
The South ◽  
South Georgia ◽  
Direct Study ◽  
Current State ◽  
Main Factors

The object of direct study represents the accumulative coast of the King Edward Bay of the South Georgia island of the same name microcontinent of Antarctica. In terms of neotectonic uplift of the island of accumulative coastal processes zone pairing of land and sea are being implemented in areas of relative tectonic subsidence. Geological-geomorphological studies and mathematical modeling of lithodynamic coastal zone give leave highlight the main factors of its current state and to justify the forecast of development in the XXI century.

Degenerative Permafrost Engineering Geology Features Analysis and Forecasting of National Road 214

2011 ◽  
Vol 105-107 ◽  
pp. 1460-1464
Author(s):  
Ping De Liu ◽  
Shuang Jie Wang ◽  
Cai Qin Wang ◽  
Long Jin
Keyword(s):  
High Speed ◽  
Engineering Geology ◽  
Meteorological Data ◽  
Ground Temperature ◽  
Frozen Ground ◽  
Southern Limit ◽  
The Road ◽  
Permafrost Table ◽  
Ice Content ◽  
National Road

The paper is based on information of permafrost engineering geology of National Road 214, and for a comparative, analysis the permafrost engineering geology features of National Road 214, Including permafrost ground temperature, ice content, natural permafrost table and artificial permafrost table; Then Summary the distribution of permafrost of National Road 214, including Southern limit of permafrost and Northern limit of permafrost, Then get one conclusion; Because of the outside temperature increase and under the influence of the role of the project, frozen ground temperature has rise trends, The permafrost along the road all tended to degenerate, Then summary its degeneration features of National Road 214, and analyze the reasons of the final degeneration; Final, combining the high-speed reconnaissance and design project National Road 214, Analysis the permafrost existing meteorological data and geological survey data, according to the frozen ice content and permafrost thickness, Then to predict and analysis permafrost degeneration tendency in numerical simulation.

scholarly journals Analysis of the Dependence between Acoustic and Physico-Mechanical Properties of Terrigenic Rocks

2021 ◽  
Vol 21 (2) ◽  
pp. 71-75
Author(s):  
Dmitriy G. Petrakov ◽  
◽  
Grigorii M. Penkov ◽  
Dmitry A. Solomoychenko ◽  
◽  
...  
Keyword(s):  
Young’S Modulus ◽  
Dynamic Modulus ◽  
Young's Modulus ◽  
Ultrasonic Waves ◽  
Acoustic Properties ◽  
Core Material ◽  
Laboratory Studies ◽  
Transverse Waves ◽  
Waves Propagation ◽  
The Relationship

During the entire development of an oil and gas field, it is necessary to carry out a complex of various studies aimed at identifying the parameters of the productive layer. One of such studies is the analysis of core material, as a result of which the following parameters of the rock are determined: porosity, permeability, Young's modulus and others. The listed characteristics must be taken into account when building a geological and hydrodynamic model of a field. In addition to these parameters, the strength properties of the rock should be determined, since they are necessary in the design of the wellbore. Such characteristics can be obtained by conducting research in specialized laboratories. This is not always possible due to various reasons. A number of studies confirm the fact of the relationship between the acoustic properties of a rock (the velocity of the longitudinal and transverse waves) and the strength characteristics. The acoustic properties of the rock must be taken into account when interpreting the acoustic logs of the wells, which allows to reveal the distribution of rocks along the wellbore. Based on the velocities of ultrasonic waves propagation, it is possible to calculate the elasticity dynamic modulus, which let assess the tendency of the rock skeleton to compaction as a result of the effective stress action. Therefore, the determination of the rock acoustic properties is necessary when planning the development of a field and its implementation. The results of laboratory studies aimed at establishing the relationship between the strength and acoustic properties of rocks are presented. During the experiment, the dynamic Young's modulus was also determined and its relationship with the speed of ultrasonic waves propagation was revealed. As a result of laboratory studies, empirical dependences of the ultimate strength in volumetric compression (σс), elasticity dynamic modulus (E ) and the velocity of transmission of longitudinal (vp) and transverse waves (vp) were obtained. An assessment of the obtained values was given over the entire measurement range.

scholarly journals Design And Evaluation of a New Auditory Display for the Pulse Oximeter

2019 ◽  
Author(s):  
Estrella Paterson ◽  
Penelope Sanderson ◽  
Neil Paterson ◽  
Robert Loeb
Keyword(s):  
Heart Rate ◽  
Pulse Oximeter ◽  
Acoustic Properties ◽  
High Fidelity ◽  
Auditory Display ◽  
Laboratory Studies ◽  
Auditory Displays ◽  
Patient Deterioration ◽  
Pulse Oximeters ◽  
Treat Patient

During surgery the pulse oximeter device provides information about a patient’s oxygen saturation (SpO2) and heart rate via visual and auditory displays. An audible tone is emitted after every detected pulse (indicating heart rate), and the pitch of the tone is mapped to SpO2. However, clinicians cannot reliably judge SpO2 using only the current auditory display. In a series of three studies, we compared auditory displays based on current pulse oximeters with displays designed to provide more information about SpO2 levels using additional acoustic properties. Results from the first two laboratory studies show that the new auditory displays support better identification of specified ranges of SpO2, and better detection of when saturation transitions a critically relevant threshold. The analysis of a third study in a high-fidelity simulator is currently under way. An auditory display that provides more information about SpO2 levels and when SpO2 changes from one range to another may be useful for clinicians when they are engaged in other visually demanding tasks but have to detect and treat patient deterioration, often in time-pressured and stressful situations.

Perceptual Dimensions of Infant Cry Signals: A Semantic Differential Analysis

1983 ◽  
Vol 57 (2) ◽  
pp. 575-581 ◽  
Author(s):  
Michael Brennan ◽  
John Kirkland
Keyword(s):  
Hierarchical Cluster ◽  
Semantic Differential ◽  
Acoustic Properties ◽  
Multivariate Techniques ◽  
Differential Analysis ◽  
Close Correspondence ◽  
Infant Cry ◽  
The Mean ◽  
Main Factors ◽  
Semantic Differential Technique

In the present study the Semantic Differential technique was used to examine perceived characteristics of infant cry sounds. 24 cries (6 each of pain, hunger, birth, and “pleasure”) were rated by 39 mothers on 50 scales. A factor analysis of the scale ratings uncovered three main factors, labelled Affect, Potency, and Evaluation, respectively. 5 “factorially-pure” scales were selected to represent each factor. A hierarchical cluster analysis of the mean factor-scale ratings uncovered 3 major cry clusters which essentially represented 3 cry-type groups, hunger, pleasure, and pain/birth. A close correspondence was found between this set of clusters and another set generated independently from cry-recognition data, indicating that the semantic differential factor-scales effectively discriminated perceptually distinct cries. This procedure adequately separates the physical (acoustic) properties of signals from their listener-perceived (auditory) ones. This distinction is not possible with studies which depend upon multivariate techniques and casts doubt on their findings.

scholarly journals Biofumigation to protect oilseed crops: focus on management of soilborne fungi of sunflower

OCL ◽  
2020 ◽  
Vol 27 ◽  
pp. 59
Author(s):  
Neïla Ait-Kaci Ahmed ◽  
Grégory Dechamp-Guillaume ◽  
Célia Seassau
Keyword(s):  
Cover Crop ◽  
Field Experiments ◽  
Macrophomina Phaseolina ◽  
Suppressive Effect ◽  
Laboratory Studies ◽  
Soilborne Diseases ◽  
Oilseed Crops ◽  
Sunflower Crop ◽  
Main Factors ◽  
Hydrolysis Of

Sunflower (Helianthus annuus L.) is one of the three most productive oilseed crops worldwide. Soilborne diseases limit yields and are challenging to manage. The fungi Verticillium dahliae, Sclerotinia sclerotiorum and Macrophomina phaseolina can survive in the soil for many years and spread. Following the ban on fumigants, biofumigation, which consists of growing, chopping and incorporating a Brassicaceae cover crop to allow biocidal compounds production in the soil, may be an alternative. Biocidal effects of the hydrolysis of glucosinolate into active compounds, such as isothiocyanates, have been shown in laboratory studies, but the effectiveness of biofumigation varies more in the field. The present study reviews the main factors that determine effective biofumigation to protect sunflower. Since the toxicity of isothiocyanates to pathogens varies widely among the latter, we reviewed studies that assessed the suppressive effect of products of glucosinolate hydrolysis on V. dahliae, S. sclerotiorum and M. phaseolina. Farmers can use many mechanisms to increase isothiocyanate production, which may protect sunflower crop effectively. Increasing biomass production and chopping the cover crop during mild temperatures and before rainy periods could increase biofumigation effectiveness. Further field experiments are needed to confirm the potential of biofumigation to control soilborne diseases of sunflower and assess potential disservices to beneficial soil communities, given their potential key role in the control of soilborne pathogens.

Hydrogen Cyanide Polymers from the Impact of Comet P/Shoemaker-Levy 9 on Jupiter

1997 ◽  
Vol 161 ◽  
pp. 179-187
Author(s):  
Clifford N. Matthews ◽  
Rose A. Pesce-Rodriguez ◽  
Shirley A. Liebman
Keyword(s):  
Amino Acids ◽  
Solar System ◽  
Hydrogen Cyanide ◽  
Nitrogen Heterocycles ◽  
Laboratory Studies ◽  
Heterogeneous Solids ◽  
The Many ◽  
Comet Halley ◽  
The Impact ◽  
By Products

AbstractHydrogen cyanide polymers – heterogeneous solids ranging in color from yellow to orange to brown to black – may be among the organic macromolecules most readily formed within the Solar System. The non-volatile black crust of comet Halley, for example, as well as the extensive orangebrown streaks in the atmosphere of Jupiter, might consist largely of such polymers synthesized from HCN formed by photolysis of methane and ammonia, the color observed depending on the concentration of HCN involved. Laboratory studies of these ubiquitous compounds point to the presence of polyamidine structures synthesized directly from hydrogen cyanide. These would be converted by water to polypeptides which can be further hydrolyzed to α-amino acids. Black polymers and multimers with conjugated ladder structures derived from HCN could also be formed and might well be the source of the many nitrogen heterocycles, adenine included, observed after pyrolysis. The dark brown color arising from the impacts of comet P/Shoemaker-Levy 9 on Jupiter might therefore be mainly caused by the presence of HCN polymers, whether originally present, deposited by the impactor or synthesized directly from HCN. Spectroscopic detection of these predicted macromolecules and their hydrolytic and pyrolytic by-products would strengthen significantly the hypothesis that cyanide polymerization is a preferred pathway for prebiotic and extraterrestrial chemistry.

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