Mike Chandler - Academia.edu (original) (raw)
Papers by Mike Chandler
CRC Press eBooks, May 25, 2006
Journal of Hydraulic Engineering, Mar 1, 2007
... (4). , based on work with submerged vertical lift gates on ogee crest weirs, reported that we... more ... (4). , based on work with submerged vertical lift gates on ogee crest weirs, reported that weir submergence did not occur until the tailwater exceeded the crest elevation. He also found that as the tailwater increased, the tailwater ...
Subsurface engineering, such as geothermal energy extraction, requires knowledge of the rupture o... more Subsurface engineering, such as geothermal energy extraction, requires knowledge of the rupture of geomaterials. Of particular importance is the time- and rate-dependence of material strength, which impacts fracture architecture and thus hydraulic conductivity and system permeability. Cyclic soft stimulation (CSS) techniques have been developed to maximise the efficiency of resource extraction whilst minimising large amplitude, fluid-injection induced seismicity. Here, we explore the benefits of cyclic stimulation experimentally, utilising novel “pulsed pumping” hydraulic fracture tests in which fluid pressure is cycled within the central borehole of a suite of 20x20cm cylinders of dense granite. The response is monitored at high-resolution by fibre-optic circumferential strain measurements, fluid pressure data and acoustic emission recording. Using cyclic high-low pressure square waves, we found that breakdown pressure was reduced by up to 15% compared to the monotonic case in whic...
<p>K values reach an asymptote between 15 and 26. DISTRUCT bar graph visualization of resul... more <p>K values reach an asymptote between 15 and 26. DISTRUCT bar graph visualization of results after permuted by CLUMPP at four different K cluster assumptions (K = 2, 5, 15, 26). Clustering based on population averages (lower bars) and individual genotypes (upper bars). The two parental species <i>Sorghum bicolor</i> and <i>Sorghum propinquum</i> are labeled as PAR.</p
<p>One of the progenitor species, <i>S</i>. <i>propinquum</i>, is u... more <p>One of the progenitor species, <i>S</i>. <i>propinquum</i>, is used as outgroup. Colonization is outlined in 5 phases (P1-P5). Major gene flow pathways are shown using arrows in four colors (red, green, blue, gray). Initial colonization from southeastern US starting from SC (red arrows) are followed by the second introduction from AZ (S2, S4 green arrows). Gene flow from TX into NM, GA and VA (P3, blue arrows) happens concurrent with local gene flow among GA-AL-SC (P3 arrows not shown for clarity). From CA, there is a massive eastward radiation into NE, KY, FL and VA (P5a, gray arrows). While there is no detectable gene flow among KS, NE and TX (P5c) there is southbound gene flow from NE to FL (S5c, gray arrow) and KS into AL and GA (P5c, arrows not shown for clarity).</p
SIGLECNRS AR 12612 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc
<p>Contingency table showing observed frequency of <i>Sorghum halepense</i> acc... more <p>Contingency table showing observed frequency of <i>Sorghum halepense</i> accessions belonging to each genetic cluster, found in each habitat type (Χ<sup>2</sup> = 121.79; df = 12; P < 0.0001).</p
<p>State boundaries overlaid for K = 15 for visual guidance. Clustering based on individual... more <p>State boundaries overlaid for K = 15 for visual guidance. Clustering based on individual genotypes (lower bars) is included for K = 15. The two parental species <i>Sorghum bicolor</i> and <i>Sorghum propinquum</i> are labeled as PAR.</p
Joint Assembly TSG-VMSG-BGA, 2017
The use of hydraulic fracturing to recover shale-gas has focused attention upon the fundamental f... more The use of hydraulic fracturing to recover shale-gas has focused attention upon the fundamental fracture properties of gas-bearing shales. Fracture propagation trajectories in these materials depend on the interaction between the anisotropic mechanical properties of the shale and the anisotropic in-situ stress field. However, there is a general paucity of available experimental data on their anisotropic mechanical, physical and fluid-flow properties, especially at elevated confining pressures.
This slide presentation provides an update on the Columbia accident response presented in 2005 wi... more This slide presentation provides an update on the Columbia accident response presented in 2005 with additional information that was not available at that time. It will provide information on the following topics: (1) medical response and Search and Rescue, (2) medico-legal issues associated with the accident, (3) the Spacecraft Crew Survival Integrated Investigation Team Report published in 2008, and (4) future NASA flight surgeon spacecraft accident response training.
The recumbent body position will isolate the crewmember from gravity and deceleration induced vas... more The recumbent body position will isolate the crewmember from gravity and deceleration induced vascular pooling away from the brain. The head shall be oriented aft. The occupant Z-axis should be parallel to the middeck floor angled no greater than 6°from the Orbiter X-axis as shown. Leg position may be bent or straight. Recumbent seating shall limit body +Gz forces to less than 0.5 G.
Weed Science, 1988
Research was conducted from 1983 through 1986 to compare the competitiveness of three cotton cult... more Research was conducted from 1983 through 1986 to compare the competitiveness of three cotton cultivars of different height with johnsongrass. Cultivars evaluated were: ‘1209-619-7’, ‘TAMCOT SP37-H’, and 'Stoneville 213’, which had an average height at maturity of 66, 122, and 168 cm, respectively. Each cultivar was grown with johnsongrass densities of 0, 4, and 6 plants/6 m of row with a 1-m row spacing. Johnsongrass biomass data confirmed that all three cultivars did compete with johnsongrass, but regression analyses using cultivar as a covariate revealed no difference in the competitiveness of the three cultivars.
Journal of Geophysical Research: Solid Earth, 2016
The use of hydraulic fracturing to recover shale gas has focused attention on the fundamental fra... more The use of hydraulic fracturing to recover shale gas has focused attention on the fundamental fracture properties of gas‐bearing shales, but there remains a paucity of available experimental data on their mechanical and physical properties. Such shales are strongly anisotropic, so that their fracture propagation trajectories depend on the interaction between their anisotropic mechanical properties and the anisotropic in situ stress field in the shallow crust. Here we report fracture toughness measurements on Mancos shale determined in all three principal fracture orientations: Divider, Short Transverse, and Arrester, using a modified short‐rod methodology. Experimental results for a range of other sedimentary and carbonate rocks are also reported for comparison purposes. Significant anisotropy is observed in shale fracture toughness measurements at ambient conditions, with values, as high as 0.72 MPa m1/2 where the crack plane is normal to the bedding, and values as low as 0.21 MPa ...
CRC Press eBooks, May 25, 2006
Journal of Hydraulic Engineering, Mar 1, 2007
... (4). , based on work with submerged vertical lift gates on ogee crest weirs, reported that we... more ... (4). , based on work with submerged vertical lift gates on ogee crest weirs, reported that weir submergence did not occur until the tailwater exceeded the crest elevation. He also found that as the tailwater increased, the tailwater ...
Subsurface engineering, such as geothermal energy extraction, requires knowledge of the rupture o... more Subsurface engineering, such as geothermal energy extraction, requires knowledge of the rupture of geomaterials. Of particular importance is the time- and rate-dependence of material strength, which impacts fracture architecture and thus hydraulic conductivity and system permeability. Cyclic soft stimulation (CSS) techniques have been developed to maximise the efficiency of resource extraction whilst minimising large amplitude, fluid-injection induced seismicity. Here, we explore the benefits of cyclic stimulation experimentally, utilising novel “pulsed pumping” hydraulic fracture tests in which fluid pressure is cycled within the central borehole of a suite of 20x20cm cylinders of dense granite. The response is monitored at high-resolution by fibre-optic circumferential strain measurements, fluid pressure data and acoustic emission recording. Using cyclic high-low pressure square waves, we found that breakdown pressure was reduced by up to 15% compared to the monotonic case in whic...
<p>K values reach an asymptote between 15 and 26. DISTRUCT bar graph visualization of resul... more <p>K values reach an asymptote between 15 and 26. DISTRUCT bar graph visualization of results after permuted by CLUMPP at four different K cluster assumptions (K = 2, 5, 15, 26). Clustering based on population averages (lower bars) and individual genotypes (upper bars). The two parental species <i>Sorghum bicolor</i> and <i>Sorghum propinquum</i> are labeled as PAR.</p
<p>One of the progenitor species, <i>S</i>. <i>propinquum</i>, is u... more <p>One of the progenitor species, <i>S</i>. <i>propinquum</i>, is used as outgroup. Colonization is outlined in 5 phases (P1-P5). Major gene flow pathways are shown using arrows in four colors (red, green, blue, gray). Initial colonization from southeastern US starting from SC (red arrows) are followed by the second introduction from AZ (S2, S4 green arrows). Gene flow from TX into NM, GA and VA (P3, blue arrows) happens concurrent with local gene flow among GA-AL-SC (P3 arrows not shown for clarity). From CA, there is a massive eastward radiation into NE, KY, FL and VA (P5a, gray arrows). While there is no detectable gene flow among KS, NE and TX (P5c) there is southbound gene flow from NE to FL (S5c, gray arrow) and KS into AL and GA (P5c, arrows not shown for clarity).</p
SIGLECNRS AR 12612 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc
<p>Contingency table showing observed frequency of <i>Sorghum halepense</i> acc... more <p>Contingency table showing observed frequency of <i>Sorghum halepense</i> accessions belonging to each genetic cluster, found in each habitat type (Χ<sup>2</sup> = 121.79; df = 12; P < 0.0001).</p
<p>State boundaries overlaid for K = 15 for visual guidance. Clustering based on individual... more <p>State boundaries overlaid for K = 15 for visual guidance. Clustering based on individual genotypes (lower bars) is included for K = 15. The two parental species <i>Sorghum bicolor</i> and <i>Sorghum propinquum</i> are labeled as PAR.</p
Joint Assembly TSG-VMSG-BGA, 2017
The use of hydraulic fracturing to recover shale-gas has focused attention upon the fundamental f... more The use of hydraulic fracturing to recover shale-gas has focused attention upon the fundamental fracture properties of gas-bearing shales. Fracture propagation trajectories in these materials depend on the interaction between the anisotropic mechanical properties of the shale and the anisotropic in-situ stress field. However, there is a general paucity of available experimental data on their anisotropic mechanical, physical and fluid-flow properties, especially at elevated confining pressures.
This slide presentation provides an update on the Columbia accident response presented in 2005 wi... more This slide presentation provides an update on the Columbia accident response presented in 2005 with additional information that was not available at that time. It will provide information on the following topics: (1) medical response and Search and Rescue, (2) medico-legal issues associated with the accident, (3) the Spacecraft Crew Survival Integrated Investigation Team Report published in 2008, and (4) future NASA flight surgeon spacecraft accident response training.
The recumbent body position will isolate the crewmember from gravity and deceleration induced vas... more The recumbent body position will isolate the crewmember from gravity and deceleration induced vascular pooling away from the brain. The head shall be oriented aft. The occupant Z-axis should be parallel to the middeck floor angled no greater than 6°from the Orbiter X-axis as shown. Leg position may be bent or straight. Recumbent seating shall limit body +Gz forces to less than 0.5 G.
Weed Science, 1988
Research was conducted from 1983 through 1986 to compare the competitiveness of three cotton cult... more Research was conducted from 1983 through 1986 to compare the competitiveness of three cotton cultivars of different height with johnsongrass. Cultivars evaluated were: ‘1209-619-7’, ‘TAMCOT SP37-H’, and 'Stoneville 213’, which had an average height at maturity of 66, 122, and 168 cm, respectively. Each cultivar was grown with johnsongrass densities of 0, 4, and 6 plants/6 m of row with a 1-m row spacing. Johnsongrass biomass data confirmed that all three cultivars did compete with johnsongrass, but regression analyses using cultivar as a covariate revealed no difference in the competitiveness of the three cultivars.
Journal of Geophysical Research: Solid Earth, 2016
The use of hydraulic fracturing to recover shale gas has focused attention on the fundamental fra... more The use of hydraulic fracturing to recover shale gas has focused attention on the fundamental fracture properties of gas‐bearing shales, but there remains a paucity of available experimental data on their mechanical and physical properties. Such shales are strongly anisotropic, so that their fracture propagation trajectories depend on the interaction between their anisotropic mechanical properties and the anisotropic in situ stress field in the shallow crust. Here we report fracture toughness measurements on Mancos shale determined in all three principal fracture orientations: Divider, Short Transverse, and Arrester, using a modified short‐rod methodology. Experimental results for a range of other sedimentary and carbonate rocks are also reported for comparison purposes. Significant anisotropy is observed in shale fracture toughness measurements at ambient conditions, with values, as high as 0.72 MPa m1/2 where the crack plane is normal to the bedding, and values as low as 0.21 MPa ...