Journal articles on the topic 'Steep site'
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1
Hough, Susan E., Alan Yong, Jean Robert Altidor, Dieuseul Anglade, Doug Given, and Saint-Louis Mildor. "Site Characterization and Site Response in Port-au-Prince, Haiti." Earthquake Spectra 27, no. 1_suppl1 (October 2011): 137–55. http://dx.doi.org/10.1193/1.3637947.
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Waveform analysis of aftershocks of the Mw7.0 Haiti earthquake of 12 January 2010 reveals amplification of ground motions at sites within the Cul de Sac valley in which Port-au-Prince is situated. Relative to ground motions recorded at a hard-rock reference site, peak acceleration values are amplified by a factor of approximately 1.8 at sites on low-lying Mio-Pliocene deposits in central Port-au-Prince and by a factor of approximately 2.5–3 on a steep foothill ridge in the southern Port-au-Prince metropolitan region. The observed amplitude, predominant periods, variability, and polarization of amplification are consistent with predicted topographic amplification by a steep, narrow ridge. A swath of unusually high damage in this region corresponds with the extent of the ridge where high weak-motion amplifications are observed. We use ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) imagery to map local geomorphology, including characterization of both near-surface and of small-scale topographic structures that correspond to zones of inferred amplification.
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Akkemik, Ünal. "TREE RINGS OF CEDRUS LIBANI AT THE NORTHERN BOUNDARY OF ITS NATURAL DISTRIBUTION." IAWA Journal 24, no. 1 (2003): 63–73. http://dx.doi.org/10.1163/22941932-90000321.
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The present study was carried out taking a total of 41 increment cores from three sites located in the northern boundary of Cedrus libani and three site chronologies were constructed. Three response functions were computed and a higher correlation with climate was found in the trees on the steep slopes. The low precipitation was an important limiting factor for growth. At the valley bottom site, neither precipitation, except for December, nor temperature, except for February were a limiting factor. The radial diameters of tracheids were measured, and the tracheid numbers representing the last seven years, from 1994 to 2000, were counted. Although the radial diameters were almost similar in all sites, the numbers of tracheids were greatest at the valley bottom site and lowest at the steep slope site.
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Porbaha, A., and D. J. Goodings. "Centrifuge modeling of geotextile-reinforced steep clay slopes." Canadian Geotechnical Journal 33, no. 5 (November 6, 1996): 696–704. http://dx.doi.org/10.1139/t96-096-317.
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When on-site soil is not granular, substantial cost savings can be achieved if a stable, steeply sloped, reinforced retaining system, backfilled with on-site fill can be sustituted for a vertical retaining wall with granular fill. Centrifuge modeling was used in this work to investigate the failure and prefailure behaviour of 14 reduced-scale geotextile-reinforced steep model slopes of 45, 63.4, 71.6°, backfilled with cohesive soil and constructed on either firm or rigid foundations. The overall performance of model slopes on firm foundations was found to be better than that of similar models on rigid foundations. A stability analysis, using the Bishop simplified method incorporating reinforcement, was found to be a good predictor of the behaviour of models. Key words: reinforced soil, centrifuge modeling, geotextile, retaining structure, slope stability.
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Dubé, Mathieu, Benoit Turcotte, and Brian Morse. "Steep channel freezeup processes: understanding complexity with statistical and physical models." Canadian Journal of Civil Engineering 42, no. 9 (September 2015): 622–33. http://dx.doi.org/10.1139/cjce-2014-0412.
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The development of ice dams in steep channels dictates water level variations and influences flow rates and habitat conditions. Despite the dominance of ice dam development in cold region gravel bed channels, practicing engineers and scientists have access to very little quantitative information describing this complex freezeup process. This paper aims to fill this gap by presenting a large data set on the process. The substantial variations observed in formation and melting rates from one site to the next and from one year to the next at the same site are explained with a physically-based numerical model that includes a complete heat budget applied to single step-pool sequence. The model successfully simulates the entire development of an ice dam and shows that the process depends on multiple parameters, or degrees of freedom. It also reveals that morphological characteristics greatly influence ice dam dynamics.
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Kim, S. S., D. Y. Kim, and H. Nho. "RISK ASSESSMENT OF STEEP SLOPE USING DRONE MAPPING AND TERRESTRIAL LIDAR IN KOREA." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLIV-3/W1-2020 (November 18, 2020): 81–86. http://dx.doi.org/10.5194/isprs-archives-xliv-3-w1-2020-81-2020.
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Abstract. Due to abnormal weather caused by climate change in recently years, natural disaster damages caused by local torrential rains have been increased over the world. Particularly, Korea is very vulnerable to landslide disasters because more than 63% of the country is mountainous and it suffers from unpredictable localized heavy rainfall during monsoon season every year. This paper presents experimental results for risk assessment of steep slope using drone mapping and terrestrial LiDAR survey. First, we acquired the aerial imagery of steep slope site by small UAV and conducted a drone mapping process with the Pix4D software. For collecting the more detailed geological data and analysing quantitatively damage of steep slopes (crack length, bedrock weathering area, etc.), we scanned steep slope area using terrestrial LiDAR system. Finally, we evaluated the applicability of public safety for outputs of UAV photogrammetry and 3D point clouds derived from terrestrial LiDAR data to analyse and assess the risk of steep slope.
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Deng, J. H., and C. F. Lee. "Displacement back analysis for a steep slope at the Three Gorges Project site." International Journal of Rock Mechanics and Mining Sciences 38, no. 2 (February 2001): 259–68. http://dx.doi.org/10.1016/s1365-1609(00)00077-0.
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Ashford, Scott A., and Nicholas Sitar. "Analysis of topographic amplification of inclined shear waves in a steep coastal bluff." Bulletin of the Seismological Society of America 87, no. 3 (June 1, 1997): 692–700. http://dx.doi.org/10.1785/bssa0870030692.
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Abstract The effect of inclined shear waves on the seismic response of a steep bluff is analyzed using generalized consistent transmitting boundaries. The results of the frequency-domain analysis of a stepped half-space subjected to incident shear waves inclined from 0° to 30° show that the motion at the crest of the slope is amplified for waves traveling into the slope and attenuated for waves traveling away from the slope, as compared to the motion in the free field behind the crest of the slope. This amplification can be as much as twice that observed for vertically propagating waves. A time-domain analysis of bluffs at Seacliff State Beach, California, is used to estimate the effect of topography using realistic conditions, taking into account wave inclination and site effects. The analysis of the site shows that although topographic amplification does in fact nearly double the amplitude of the motion in some cases, this amplification is offset by reduced site amplification and by wave splitting at material interfaces. Thus, the actual peak acceleration occurring at the crest of the slope changes little with incident angle as compared to the amplification of the free-field motion and actually decreases in many cases. Though a more general study is recommended, these results suggest that wave orientation and inclination substantially increase topographic amplification; however, it may be adequate to only account for vertically propagating waves for site response and slope stability analyses where only the magnitude of acceleration is considered.
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Nicoll, Bruce C., Alexis Achim, Shaun Mochan, and Barry A. Gardiner. "Does steep terrain influence tree stability? A field investigation." Canadian Journal of Forest Research 35, no. 10 (October 1, 2005): 2360–67. http://dx.doi.org/10.1139/x05-157.
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The anchorage of 40-year-old Sitka spruce (Picea sitchensis (Bong.) Carr.) trees grown in a plantation on a steep (ca. 30°) slope was compared with that of trees grown on an adjacent horizontal area. There was similar gleyed mineral soil on the sloping and horizontal areas. Trees were mechanically overturned using a winch, and anchorage was quantified by measuring load, stem angle, and tree dimensions. Trees on the slope were overturned upslope, downslope, or across-slope. Critical turning moments were calculated around the tree base and the actual hinge point. Critical wind speeds required to uproot or snap trees in this stand were modelled to compare the vulnerability of trees to upslope and downslope winds. No overall difference in anchorage was found between trees grown on the horizontal and sloping parts of the site. However, for trees on the slope, those pulled upslope showed significantly more resistance to overturning for a given stem mass than those pulled downslope. Critical turning moments calculated at the hinge point were smaller than those calculated at the stem base, but differences were small and had no effect on the comparison between treatments. Critical wind speeds for uprooting were estimated to be 28 m·s1 for an upslope wind and 24 m·s1 for a downslope wind on this site. The implications of these results are discussed in relation to windthrow-risk modelling and forest soil conservation.
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Strub, Larissa, and Simone Mueller Loose. "The cost disadvantage of steep slope viticulture and strategies for its preservation." OENO One 55, no. 1 (January 8, 2021): 49–68. http://dx.doi.org/10.20870/oeno-one.2021.55.1.4494.
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The falling fallow of steep slope vineyards is caused by cost disadvantages that have not been analysed so far. This study quantified the production costs of different types of steep slopes, identified cost drivers within viticultural processes and assessed the impact of grape yield on the production cost for vertical shoot positioning (VSP) systems. It also examined under what conditions the reshaping of steep slope vineyards into transversal terraces (TTs) is economically viable. Costs were derived from a dataset of 2321 working time records for labour and machine hours from five German wine estates over three years. The costs for standard viticultural processes were compared across five site types with different mechanisation intensities by univariate analysis of variance with fixed and random effects. The net present value (NPV) of reshaping slopes into horizontal terraces was also assessed. Manual management of steep slopes was determined to be 2.6 times more costly than standard flat terrain viticulture. The cost disadvantage of steep slopes mainly stems from viticultural processes with limited mechanisability that require specialised equipment and many repetitions. Current subsidies fall short of covering the economic disadvantage of manual and rope-assisted steep slopes. Climate change-related drought and yield losses further increase the economic unsustainability of steep slopes. Under certain conditions, the transformation of manual steep slope sites into TTs can be a viable economic option. Strategies to reduce the cost disadvantage are outlined. The estimated cost benchmarks provide critical input for steep slope wine growers’ cost-based pricing policy. These benchmarks also give agricultural policy reliable indicators of the subsidies required for preserving steep slope landscapes and of the support needed to transform manual steep slope sites into TTs.
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Strub, Larissa, and Simone Mueller Loose. "The cost disadvantage of steep slope viticulture and strategies for its preservation." OENO One 55, no. 1 (January 8, 2021): 49–68. http://dx.doi.org/10.20870/oeno-one.2021.55.1.4494.
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The falling fallow of steep slope vineyards is caused by cost disadvantages that have not been analysed so far. This study quantified the production costs of different types of steep slopes, identified cost drivers within viticultural processes and assessed the impact of grape yield on the production cost for vertical shoot positioning (VSP) systems. It also examined under what conditions the reshaping of steep slope vineyards into transversal terraces (TTs) is economically viable. Costs were derived from a dataset of 2321 working time records for labour and machine hours from five German wine estates over three years. The costs for standard viticultural processes were compared across five site types with different mechanisation intensities by univariate analysis of variance with fixed and random effects. The net present value (NPV) of reshaping slopes into horizontal terraces was also assessed. Manual management of steep slopes was determined to be 2.6 times more costly than standard flat terrain viticulture. The cost disadvantage of steep slopes mainly stems from viticultural processes with limited mechanisability that require specialised equipment and many repetitions. Current subsidies fall short of covering the economic disadvantage of manual and rope-assisted steep slopes. Climate change-related drought and yield losses further increase the economic unsustainability of steep slopes. Under certain conditions, the transformation of manual steep slope sites into TTs can be a viable economic option. Strategies to reduce the cost disadvantage are outlined. The estimated cost benchmarks provide critical input for steep slope wine growers’ cost-based pricing policy. These benchmarks also give agricultural policy reliable indicators of the subsidies required for preserving steep slope landscapes and of the support needed to transform manual steep slope sites into TTs.
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Mariolakos, I., V. Nikolopoulos, I. Bantekas, and N. Palyvos. "ORACLES ON FAULTS: A PROBABLE LOCATION OF A “LOST” ORACLE OF APOLLO NEAR OROVIAI (NORTHERN EUBOEA ISLAND, GREECE) VIEWED IN ITS GEOLOGICAL AND GEOMORPHOLOGICAL CONTEXT." Bulletin of the Geological Society of Greece 43, no. 2 (January 23, 2017): 829. http://dx.doi.org/10.12681/bgsg.11249.
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At a newly discovered archaeological site at Aghios Taxiarches in Northern Euboea, two votive inscribed stelae were found in 2001 together with hellenistic pottery next to ancient wall ruins on a steep and high rocky slope. Based on the inscriptions and the geographical location of the site we propose the hypothesis that this is quite probably the spot where the oracle of “Apollo Selinountios” (mentioned by Strabo) would stand in antiquity. The wall ruins of the site are found on a very steep bedrock escarpment of an active fault zone, next to a hanging valley, a high waterfall and a cave. The geomorphological and geological environment of the site is linked directly to the regional geodynamical context of Central Greece, a region of tectonic turmoil throughout the Pleistocene and Holocene, characterised by distinct landscapes produced by the activity of active fault zones, intense seismicity, and in part, volcanism and hydrothermal activity. The geomorphological and geological similarities of the Ag. Taxiarches site with those of the oracle at Delphi, seem to provide further support to the hypothesis that the former site can well be that of an ancient oracle, given the recently established connections between the geological environment at Delphi and Apollo’s oracle there. Definitive verification of our hypothesis can only be obtained by further, detailed archaeological study, whereas geological/geomorphological, geochemical, and geochronological studies would be necessary to clarify the connection that the cave lying next to the wall remains may had with the site’s function.
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Williams, Gray A., Colin Little, David Morritt, Penny Stirling, Linda Teagle, Alison Miles, Graham Pilling, and Mireille Consalvey. "Foraging in the limpet Patella vulgata: the influence of rock slope on the timing of activity." Journal of the Marine Biological Association of the United Kingdom 79, no. 5 (October 1999): 881–90. http://dx.doi.org/10.1017/s0025315498001040.
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Preliminary observations of limpet activity at Lough Hyne, in south-west Ireland, showed that individuals on steep slopes were primarily active at night, when emersed; while those on near-horizontal rocks were often active during daytime submersion. Observations of limpet populations over an 11 d period of limpet populations on a near-vertical and a near-horizontal site, only 45 m apart, confirmed that animals on the near-vertical site were active on nocturnal low tides, whilst those on the near-horizontal site were active on daytime high waters. A short-term survey at ten sites, which had limpets on both extremes of slope (i.e. either near-vertical or near-horizontal), showed that limpets on near-horizontal surfaces were, on average, more active at daytime high waters than those on near-vertical faces. In 1996 and 1997 surveys of activity at daytime high, and nocturnal low waters were conducted at sites (14–15) with varying rock slopes (∼3–87°). In all cases, limpets on more steep slopes were active at nocturnal emersion whilst animals on more gentle slopes were active on daytime submersion periods. In most cases these trends were significant and explained between 22–40% and 37–44% of the variation in activity with site in 1996 and 1997 respectively. Analysis of the head orientation of limpets on their home scars showed that animals orientated in a down shore direction at all sites (1997 data) suggesting that limpets do perceive and respond to slope. Whilst slope does appear to influence the timing of limpets' activity (and especially on very steep or gently sloping sites) it does not account for a large degree of the variation in activity and, on sites with slopes between 30 and 60°, is likely to work in combination with other factors.
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Saber, Saber Ahmed, Zuhair Rejeb, and Mark Altaweel. "REPORT ON THE EXCAVATIONS AT MERQULY: THE 2009 SEASON." Iraq 76 (December 2014): 231–44. http://dx.doi.org/10.1017/irq.2014.9.
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The site of Merquly is located in a mountain pass c. 40 km north-west of Slemani (Sulaimaniyah), Iraq. Excavation at the site in 2009 revealed a fortified structure whose rooms at multiple elevations reflect a terraced structure adapted to the steep landscape contours of its setting. Both architectural preservation and quantity of finds were relatively limited; however, despite the nearby presence of a prominent Parthian period rock relief, ceramics suggest a later Sasanian date for the site. The authors discuss the 2009 season's results, and consider possible parallels for the preserved architecture, although further work is needed to securely date and characterize the site.
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Rossi, Fernando, Johannes Breidenbach, Stefano Puliti, Rasmus Astrup, and Bruce Talbot. "Assessing Harvested Sites in a Forested Boreal Mountain Catchment through Global Forest Watch." Remote Sensing 11, no. 5 (March 6, 2019): 543. http://dx.doi.org/10.3390/rs11050543.
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Global Forest Watch (GFW) provides a global map of annual forest cover loss (FCL) produced from Landsat imagery, offering a potentially powerful tool for monitoring changes in forest cover. In managed forests, FCL primarily provides information on commercial harvesting. A semi-autonomous method for providing data on the location and attributes of harvested sites at a landscape level was developed which could significantly improve the basis for catchment management, including risk mitigation. FCL in combination with aerial images was used for detecting and characterising harvested sites in a 1607 km2 mountainous boreal forest catchment in south-central Norway. Firstly, the forest cover loss map was enhanced (FCLE) by removing small isolated forest cover loss patches that had a high probability of representing commission errors. The FCLE map was then used to locate and assess sites representing annual harvesting activity over a 17-year period. Despite an overall accuracy of >98%, a kappa of 0.66 suggested only a moderate quality for detecting harvested sites. While errors of commission were negligible, errors of omission were more considerable and at least partially attributed to the presence of residual seed trees on the site after harvesting. The systematic analysis of harvested sites against aerial images showed a detection rate of 94%, but the area of the individual harvested site was underestimated by 29% on average. None of the site attributes tested, including slope, area, altitude, or site shape index, had any effect on the accuracy of the area estimate. The annual harvest estimate was 0.6% (standard error 12%) of the productive forest area. On average, 96% of the harvest was carried out on flat to moderately steep terrain (<40% slope), 3% on steep terrain (40% to 60% slope), and 1% on very steep terrain (>60% slope). The mean area of FCLE within each slope category was 1.7 ha, 0.9 ha, and 0.5 ha, respectively. The mean FCLE area increased from 1.0 ha to 3.2 ha on flat to moderate terrain over the studied period, while the frequency of harvesting increased from 249 to 495 sites per year. On the steep terrain, 35% of the harvesting was done with cable yarding, and 62% with harvester-forwarder systems. On the very steep terrain (>60% slope), 88% of the area was harvested using cable yarding technology while harvesters and forwarders were used on 12% of the area. Overall, FCL proved to be a useful dataset for the purpose of assessing harvesting activity under the given conditions.
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Ma, Qing Wen, Tuan Jie Wang, and Ke Bin Ren. "Stability Analysis of Xiping Hotel Iron Sites Based on Expansive Soil and Steep Slope." Applied Mechanics and Materials 438-439 (October 2013): 1380–84. http://dx.doi.org/10.4028/www.scientific.net/amm.438-439.1380.
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Xiping iron smelting site is the fourth installment of the national key cultural relics protection units. The protective house is surrounded by water, with its base on expansive soil. With the influence of the slide of dams during the flood season, a lot of cracks occur in the protective house and its surrounding, resulting in severe potential danger to iron smelting site. The effect of expansive soil, steep slope reservoir and rainfall on house deformation is analyzed, qualitative and quantitative analysis on slope stability is conducted, results indicates that the protective house will be damaged under rainstorm or continuous precipitation, basic stability will be lose under natural condition.
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Liu, Yang, Kaiwen Zhang, Denghang Tian, Liming Qu, and Yang Liu. "Research on Deep-Site Failure Mechanism of High-Steep Slope under Active Fault Creeping Dislocation." Shock and Vibration 2021 (August 19, 2021): 1–12. http://dx.doi.org/10.1155/2021/4482523.
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The reverse thrust in the deep site causes the upward propagation of stress and displacement in the overlying soil. The displacement field around the fault zone is maximum. As the spatial location becomes shallower, the soil displacement gradually becomes smaller. The deformation of the overlying soil is mainly affected by the vertical dislocation of the fracture zone. The monitoring curve showed no abrupt change value, indicating that the top surface of soil did not rupture, and only the influence of fault on the displacement transfer of the top surface of the soil. When a creeping dislocation occurs in the bottom fracture zone, the maximum principal stress of the upper boundary of the deep site is dominated by compressive stress. The maximum principal stress of the soil on both sides of the fracture zone has a maximum value, and the soil on the right side of the fracture zone has a significant compression effect. The maximum principal stress monitoring curve varies greatly, indicating the plastic failure development of soil, which is the same as the research results of the plastic failure zone in the following paper. When the bottom fracture zone starts to move, the plastic zone first appears at the junction area between the front end of the bottom fracture zone and the overlying soil. As the amount of dislocation of the fracture zone increases, the plastic zone continues to extend into the inner soil. The left and right sides of the fracture zone show tensile failure and compression failure, respectively. The development of the upper envelope curve in the plastic zone of the overlying soil satisfies the Boltzmann equation with a first-order exponential growth, while the development of the lower envelope curve satisfies the Gauss equation with a second-order exponential growth. The development curve equation of the plastic zone is verified according to the residual figures of the fitting result and the correlation parameters.
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Tazina, Natal'ya Georgievna, Valentina Ivanovna Darchiya, and Sergey Nikolaevich Chernyshev. "Erosion protection Phytoreinforcement of SCARP steep slopes of the holy virgin’s DITCH." Vestnik MGSU, no. 9 (September 2015): 83–94. http://dx.doi.org/10.22227/1997-0935.2015.9.83-94.
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Erosion protection landscaping embedment of steep subsoil slopes is a time-sensitive issue of road construction and planning of recreational area that are often fit on a challenging picturesque terrain unsuitable for site development. The article provides the results of a 4-year experiment on landscaping and plant fixing of up to 4.5 m soil slopes with 1:1 and 2:1 grades; the experiment was carried out by the MGSU on the territory of a convent in the south of the Nizhniy Novgorod region. The site has slopes oriented towards all cardinals. At some places the slopes are bedimmed by trees. All these factors create a wide range of geo-ecological conditions for lawns. All the slopes are fixed with geo-fibrefill grids; slopes with 2:1 grade are strengthened by auxiliary grids made of reinforced metal bars, anchors and braces on the bottom of the Holy Moat. The paper recommends composition of grass plants as well as techniques to build up lawns suitable for various micro-climate conditions. It also advises the structure of multi-tier plant entity. The suggested methods are tested during a 3-year maintenance of slopes built for constant use.
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Li, Yongle, Xinyu Xu, Mingjin Zhang, and Youlin Xu. "Wind tunnel test and numerical simulation of wind characteristics at a bridge site in mountainous terrain." Advances in Structural Engineering 20, no. 8 (November 3, 2016): 1223–31. http://dx.doi.org/10.1177/1369433216673377.
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Wind tunnel test and computational fluid dynamics simulation were conducted to study the wind characteristics at a bridge site in mountainous terrain. The upstream terrains were classified into three types: open terrain, open terrain with a steep slope close to the bridge, and open terrain with a ridge close to the bridge. Results obtained from the two methods were compared, including mean speed profiles in the vertical direction and variations of wind speed and angle of attack along the bridge deck. In addition, turbulence intensities at the bridge site obtained from wind tunnel test were discussed. For mean speed profiles in the vertical direction, two methods are reasonably close for open terrain, while mountain shielding effects are evident for open terrain with a steep slope for both the methods, but the extents of effects appear different. Wind speed and angle of attack along the bridge deck are mainly influenced by the local terrain. Strong downslope wind is generated at the lee slope for the case of wind normal to top of the ridge. The comparative results are expected to provide useful references for the study of wind characteristics in mountainous terrain in the future.
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Cheng, Guo Ming, Tong Zu Liu, and Bin Zhi. "Numerical Modeling of Subsidence-Induced Stress on the Pipeline in Steep Seam Mining." Applied Mechanics and Materials 448-453 (October 2013): 3863–68. http://dx.doi.org/10.4028/www.scientific.net/amm.448-453.3863.
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In China, surface subsidence caused by steep coal seam mining has affected the safe operation of pipelines in recent years. The study site is one coal mine, where the gas pipeline from Shanshan to Urumqi is across. FLAC3D was adopted to study subsidence-induced stress on the pipeline, and the numerical model was calibrated with the measurement data. Visualization of alarm levels on the pipeline was obtained by integrating the usage of Fish function embedded in FLAC3D and Tecplot. The simulations reveal that the stress on the pipeline is closely related to the excavation depth. The stress on the pipeline increases with the excavation depth increasing when mining the 1st, 2nd, and 3rd levels, whereas the stress on the pipeline decreases slightly with the excavation depth increasing when mining the fourth, fifth, and sixth levels. The maximum stress on the pipeline occurs after mining the 3rd level. The possible damage to the pipe is at the upper-right side. Therefore, the results are helpful to prevent and reduce the impact of subsidence on the pipeline.
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Wright, Kenneth R. "The Masterful Water Engineers of Machu Picchu." Water 13, no. 21 (November 1, 2021): 3049. http://dx.doi.org/10.3390/w13213049.
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The water engineering achievements of the Inca at Machu Picchu, when defined in technical terms common to modern engineers, demonstrate that the Inca were masterful planners, designers, and constructors. They demonstrated their technical skills through the planning, design, and construction of water supply, fountains, terraces, foundations, walls, and trails. The site of Machu Picchu was a difficult place to build, with high precipitation, steep terrain, and challenging access. Nonetheless, the Inca had the uncanny ability to plan public works and infrastructure in a manner that fit this problematic site and lasted for centuries.
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Lee, Jae-Joon, Woo-Song Jeong, Moon-Soo Song, Sang-Guk Yum, and Ji-Sung Kim. "Suggestions of Principles to Reduce the Deviation of Steep Slope Evaluation Results through On-Site Evaluation." Applied Sciences 12, no. 16 (August 12, 2022): 8102. http://dx.doi.org/10.3390/app12168102.
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Geup Kyung Sa Ji (GGSJ) is the term used to refer to steep slopes managed by the Ministry of Interior and Safety (MOIS). The MOIS is a government agency of South Korea in charge of administration and safety, with evaluations and management carried out by local governments. There are 16,071 GGSJs as of March 2022. However, it is difficult to determine whether the evaluation results for these GGSJs are reliable and whether data are managed efficiently. Unlike the Ministry of Land, Infrastructure and Transport and the Korea Forest Service, there are personnel in charge of the relevant administration and welfare operations who are not experts in GGSJs. Therefore, a method for evaluating the currently managed steep slopes and the problems that arise in the process must be identified through evaluation by experts and non-experts in the field. Additionally, methods to increase the consistency and reliability of evaluation results must be determined. This study proposes methods designed to solve the problem of differences in evaluation results caused by the diversity of perspectives on the evaluation of GGSJs and which can be used in the assessment of complex slopes. This study aims to increase the efficiency and consistency of evaluation results in the integrated management of GGSJs to build trust among management staff.
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Pierpoint, C. "Harbour porpoise (Phocoena phocoena) foraging strategy at a high energy, near-shore site in south-west Wales, UK." Journal of the Marine Biological Association of the United Kingdom 88, no. 6 (March 17, 2008): 1167–73. http://dx.doi.org/10.1017/s0025315408000507.
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Harbour porpoises (Phocoena phocoena) visit Ramsey Sound at specific states of tide to feed. The preferred foraging location is high-energy habitat in South Ramsey Sound where a tide race, overfalls and upwelling zones form during the ebb phase. Seabed topography and tidal currents combine to create a foraging resource exploited by harbour porpoises at regular and predictable intervals. Porpoises are observed surfacing repeatedly directly into the tidal stream above and adjacent to, a steep-sided trench on the seabed. Tidal currents and the steep walls of the trench are believed to concentrate prey which is funnelled towards the waiting porpoises. Schools with calves prefer areas on the periphery of the fastest flowing water, where current speeds are lower. The presence of harbour porpoises is restricted almost entirely to the ebb tidal phase, but porpoises regularly occupy this site for the entire ebb phase. Harbour porpoise foraging in a tide race habitat is widely reported from the geographical range of the harbour porpoise and raises issues regarding foraging strategy and the net energetic value of hunting prey in high-energy environments.
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Nicollier, Tobias, Gilles Antoniazza, Lorenz Ammann, Dieter Rickenmann, and James W. Kirchner. "Toward a general calibration of the Swiss plate geophone system for fractional bedload transport." Earth Surface Dynamics 10, no. 5 (September 19, 2022): 929–51. http://dx.doi.org/10.5194/esurf-10-929-2022.
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Abstract. Substantial uncertainties in bedload transport predictions in steep streams have encouraged intensive efforts towards the development of surrogate monitoring technologies. One such system, the Swiss plate geophone (SPG), has been deployed and calibrated in numerous steep channels, mainly in the Alps. Calibration relationships linking the signal recorded by the SPG system to the intensity and characteristics of transported bedload can vary substantially between different monitoring stations, likely due to site-specific factors such as flow velocity and bed roughness. Furthermore, recent flume experiments on the SPG system have shown that site-specific calibration relationships can be biased by elastic waves resulting from impacts occurring outside the plate boundaries. Motivated by these findings, we present a hybrid calibration procedure derived from flume experiments and an extensive dataset of 308 direct field measurements at four different SPG monitoring stations. Our main goal is to investigate the feasibility of a general, site-independent calibration procedure for inferring fractional bedload transport from the SPG signal. First, we use flume experiments to show that sediment size classes can be distinguished more accurately using a combination of vibrational frequency and amplitude information than by using amplitude information alone. Second, we apply this amplitude–frequency method to field measurements to derive general calibration coefficients for 10 different grain-size fractions. The amplitude–frequency method results in more homogeneous signal responses across all sites and significantly improves the accuracy of fractional sediment flux and grain-size estimates. We attribute the remaining site-to-site discrepancies to large differences in flow velocity and discuss further factors that may influence the accuracy of these bedload estimates.
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Himmelbauer, Margarita L., Violeta Vateva, Ljudmila Lozanova, Willibald Loiskandl, and Svetla Rousseva. "Site effects on root characteristics and soil protection capability of two cover crops grown in South Bulgaria." Journal of Hydrology and Hydromechanics 61, no. 1 (March 1, 2013): 30–38. http://dx.doi.org/10.2478/johh-2013-0005.
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Abstract Water erosion has been recognized as a major soil degradation process worldwide. This is of special relevance in the semi-arid areas of South Bulgaria with long periods of drought along with severe rainfall events. The main objective of this study was to evaluate the applicability of Bromus innermis L. and Lotus corniculatus L. for soil protection purposes under different site conditions. The site parameters considered were slope, fertilization and a range of soil physical parameters. The plant parameters were canopy cover, biomass, and root morphological characteristics. The experiment includes plots without and with eleven rates of NPK fertilization on gentle (6o) and steep slopes (12o). It was observed that the effect of fertilization on shoot and root growth was stronger on the gentle than on the steep slopes. The biomass accumulation was more sensitive to N than the PK fertilizer applications. The increase of the root density with increasing fertilization rates was more pronounced for the mass than for length or surface area. A significant effect on root diameter was found only for the variants with the highest N application. Treatments with the highest root mass density on both slopes showed the greatest potential for reducing erosion.
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Li, Ching-Chia, Tsu-Ming Chien, Shu-Pin Huang, Hsin-Chih Yeh, Hsiang-Ying Lee, Hung-Lung Ke, Sheng-Chen Wen, et al. "Single-Site Sutureless Partial Nephrectomy for Small Exophytic Renal Tumors." Journal of Clinical Medicine 9, no. 11 (November 13, 2020): 3658. http://dx.doi.org/10.3390/jcm9113658.
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Partial nephrectomy (PN) is the standard procedure for most patients with localized renal cancer. Laparoscopy has become the preferred surgical approach to target this cancer, but the steep learning curve with laparoscopic PN (LPN) remains a concern. In LPN intracorporeal suturing, the operation time is further extended even under robot assistance, a step which prolongs warm ischemic time. Herein, we shared our experience to reduce the warm ischemia time, which allows surgeons to perform LPN more easily by using a combination of hemostatic agents to safely control parenchymal bleeding. Between 2015 and 2018, we enrolled 52 patients who underwent LPN in our hospital. Single-site sutureless LPN and traditional suture methods were performed in 33 and 19 patients, respectively. Preoperative, intra-operative, and postoperative variables were recorded. Renal function was evaluated by estimated glomerular filtration rate (eGFR) pre- and postoperatively. The average warm ischemia time (sutureless vs. suture group; 11.8 ± 3.9 vs. 21.2 ± 7.2 min, p < 0.001) and the operation time (167.9 ± 37.5 vs. 193.7 ± 42.5 min, p = 0.035) were significantly shorter in the sutureless group. In the sutureless group, only 2 patients suffered from massive urinary leakage (>200 mL/day) from the Jackson Pratt drainage tube, but the leakage spontaneously decreased within 7 days after surgery. eGFR and serum hemoglobin were not found to be significantly different pre- and postoperatively. All tumors were removed without a positive surgical margin. All patients were alive without recurrent tumors at mean postoperative follow-ups of 29.3 ± 12.2 months. Single-site sutureless LPN is a feasible surgical method for most patients with small exophytic renal cancer with excellent cosmetic results without affecting oncological results.
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Noerwidi, Sofwan. "ANALISIS CAKUPAN SITUS-SITUS PERMUKIMAN NEOLITIK DI BANYUWANGI SELATAN." Berkala Arkeologi 33, no. 1 (May 31, 2013): 13–32. http://dx.doi.org/10.30883/jba.v33i1.2.
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Economic calculations as cost-benefit ratios are used by prehistoric people in exploiting their natural resources. This paper will discuss about landscape and natural resources to reconstruct the site catchment area which explored by Neolithic people at South Banyuwangi in prehistoric times. In the Site Catchment Analysis for traditional farmer, a preliminary of 1-km radius site catchment zone is the most basic or regular subsistence resources, and 5-km radii is largely the maximum limits of radius distance. Based on hypotheses of catchment zone, we analyzed its natural resource inside eachcatchment zone. This analysis conducted on landscape conditions (hills, plains, steep cliffs), water sources (springs, rivers and water basins). Comparison between environmental conditions inside the catchment zone and artifact findings (from survey and excavation work) is obtained to predict the site catchment pattern of Neolithic settlement sites at South Banyuwangi.
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Wang, Shenghui, Qi Ou, Shengfeng Lei, Huaqi Liu, Shuaitao Mao, Qizhe Zhang, Jian Liu, and Fangcheng Lv. "Study on the Measurement of the On-Site Overvoltage and Internal Temperature Rise Simulation of the EMU Arrester." Applied Sciences 12, no. 15 (August 8, 2022): 7925. http://dx.doi.org/10.3390/app12157925.
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In order to analyze the explosion accidents of the CRH5 EMU roof arrester in recent years, an internal temperature measuring platform based on fluorescence fiber was established, and the temperature distribution characteristics under the continuous operating voltage and high-current impulse were analyzed. The test results show that passing section overvoltage and steep impulse overvoltage have higher amplitudes, while high-harmonic overvoltage has a lower amplitude but a longer duration. The maximum temperature rise of the arrester was 5.2 °C under 34 kV for 3 h. The surface temperature of the valve plate column was high in the middle and low on both sides; the maximum temperature difference at different positions was only 2.2 °C. The maximum temperature of the valve plate column rose to 97.6 °C under 105 times of the high-current impulse, and the maximum temperature difference at different positions reached 33.8 °C. Then, the actual overvoltage of the arrester in operation was measured and analyzed statistically, and the arrester simulation model was established. The temperature characteristics of the normal arrester and the arrester with the electric tree were studied under the actual typical overvoltage, and the influence of air velocity on the internal temperature rise was analyzed. The simulation results show that, due to the low amplitude and small current of high-harmonic overvoltage, the internal temperature rise of the normal and defective arresters was very small. Under the effects of passing section overvoltage and steep impulse overvoltage, the internal temperature of the normal arrester can reach 36.57 °C and 241 °C, and the arrester with the electric tree defect can reach 44.75 °C and 536 °C, respectively. The air velocity has little effect on the internal temperature rise of the arrester. Passing section overvoltage and steep impulse overvoltage occur frequently and have an obvious influence on the internal temperature rise of the arrester, so the roof overvoltage of the EMU is an important reason for the arrester burst.
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Jiang, Peng, Jin Li, Shen Zuo, and Xin Zhuang Cui. "Ecological Retaining Wall for High-Steep Slopes: A Case Study in the Ji-Lai Expressway, Eastern China." Advances in Civil Engineering 2020 (July 24, 2020): 1–13. http://dx.doi.org/10.1155/2020/5106397.
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Research on the retaining structures for high-steep slopes is extremely significant because of its real-world applications and far-reaching implications. A flexible geocell-reinforced ecological retaining wall as a high-steep slope protection scheme was developed and applied to the slope protection project of the Ji-Lai Expressway by analyzing the reinforcement mechanism of the geocell used. The lateral displacement and Earth pressure distribution on the flexible ecological retaining wall applied to the high-steep slope were studied using finite element numerical simulations and verified using field experiments. Results reveal that the wall maximum horizontal displacement is 2/3 H away from the wall toe because of the replacement of the upper part of soil. There is an obvious bucking effect on the active Earth pressure around the stiffened site, and the flexible deformation of the retaining wall helped effectively release some of the Earth pressure. Consequently, the measured value is lower than the theoretical value. Through this case study, it is demonstrated that the flexible ecological retaining wall as a slope protection technology can be successfully applied to steep slopes with a height of more than 15 m. Moreover, it brings significant advantages for protecting the ecological environment and improving the highway landscape.
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Kostyuk, Svetlana, Nikolay Bedarev, Oleg Lyubimov, and Nikolay Kovalyov. "Searching for the Optimal Parameters of the Thick Steep Seams‘ Under-Level Development." E3S Web of Conferences 41 (2018): 01002. http://dx.doi.org/10.1051/e3sconf/20184101002.
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At the present time the problem to search for variants for the development of steep thick coal seams is highly interest. Here there are, for example, variants for managing the workings’ roof by caving or laying the worked out space. The authors proposed a number of methods for it, which are protected by patents. The permissible span of the roof exposure is estimated as a function of the type of the immediate roof of the mine, its thickness, bulk density and tensile strength, and the height of the underlevel is also determined. The technical result is provided by the presence of the protective inter-horizon strips and inter-sectional pillars, by the order of working out the excavation site and by the value of the step of the binding of the worked out space. The above solutions are acceptable for the Prokopyevsk-Kiselevsk coal region in Kuzbass.
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Douglas, George W., and Jenifer L. Penny. "Conservation Evaluation of the Small-flowered Tonella, Tonella tenella, in Canada." Canadian Field-Naturalist 120, no. 2 (April 1, 2006): 179. http://dx.doi.org/10.22621/cfn.v120i2.284.
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In Canada, the Small-flowered Tonella, Tonella tenella, is restricted to the west side of Saltspring Island in the Gulf Islands of southwestern British Columbia. This population represents the northern limits of the species which is disjunct from its main range in southern Washington (Columbia River gorge), through Oregon to central California. In British Columbia, Tonella tenella is associated with rock outcrops and dry, steep, sparsely forested talus slopes at elevations of 50 to 300 m. The population on Saltspring Island is on private property and not directly imperilled at this time. There is, however, a potential for housing development in the future on this waterfront site, thus the authors consider the species endangered.
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Rodionov, A. M., and D. S. Tolstykh. "Use-Wear Analysis of the Stone and Bone Industry of Kostenki-9 Site (Based on Material of 2006–2007 Field Research)." Vestnik NSU. Series: History and Philology 21, no. 3 (March 21, 2022): 21–31. http://dx.doi.org/10.25205/1818-7919-2022-21-3-21-31.
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Purpose. The article discusses the results of a use-wear analysis of artifacts from the Kostenki 9 site (Biriutchii log). The site is located in the Middle Don River valley on the southwest of the Russian Plain. Kostenki 9 is related to the group of Paleolithic sites in the Kostenki-Borshchevo locality. Our investigation indicates that paleoeconomy of the local inhabitants was based on the strategies of high specialization.Results. The authors highlight the main types of stone implements and the main technological methods of production. The inhabitants of the site mainly used chalk flint. Knapping technique is prismatic, the main type of workpiece is a blade. For the secondary processing of blanks, site's inhabitants most often used steep and semi-steep dull retouching. Less commonly, flat unilateral or bilateral, marginal, deeply protruding onto the blade’s dorsal surface. On the basis of use-wear analysis, as well as some experiments, the authors came to the following conclusion: the stone industry of the site has Gravettian features. However, it does not have pronounced diagnostic forms.Conclusion. The primary type of activity revealed at the Kostenki 9 site is butchering of animal carcasses. Studied use-wear traces on the stone inventory support this conclusion. The second activity represents wood processing. The ancient inhabitants of the Kostenki 9 made the wooden shafts for the darts and spears. Analysis of bone implements revealed several exciting traits. Inhabitants possessed all the basic techniques of bone processing: making grooves and cutting along the circumference. The collection does not include any tools that can be interpreted as hunting bone weapons. This thesis confirms the assumption that the inhabitants of the Kostenki 9 site used wood for tool-making, while the bones and ivory were kept for production of non-utilitarian objects. The cultural identity of the assemblage raises questions. The closest are lithic collections from the Gravettian sites Borshchevo 5 and Kostenki 8.
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Whitehead, J. H., and A. Leventhal. "On-site wastewater management system design and landslide risk assessment." Water Science and Technology 51, no. 10 (May 1, 2005): 55–63. http://dx.doi.org/10.2166/wst.2005.0351.
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On-site wastewater management system design and performance is significant in assessing landslide risk in areas with potential for slope instability. Much of the development in Pittwater, NSW, local government area is on steep coastal land which has a history of slope instability. Concern over cases of poorly performing or failing on-site wastewater systems and the recognition that these and newly designed systems could be contributory to slope instability has been a factor in Pittwater Council, NSW, requiring that landslide risk assessment be undertaken for new and amended on-site wastewater management systems in potentially unstable areas. This paper describes the wastewater management system design and landslide risk assessment undertaken at Pittwater Youth Hostel in accordance with the Australian Geomechanics Society's Geotechnical Risk Management procedure to comply with the Pittwater Policy. The work completed illustrates both necessary and effective interaction of the wastewater and geotechnical professions to achieve a successful outcome for the client. It is likely that this professional interaction will be increasingly common along the NSW coast and elsewhere.
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Dovhal, V. Yu. "INVESTIGATION OF THE MANIFESTATIONS OF ROCK PRESSURE IN A DEEP MINE WITH A STEEP OCCURRENCE OF COAL SEAMS." Labour protection problems in Ukraine 37, no. 2 (June 30, 2021): 44–50. http://dx.doi.org/10.36804/nndipbop.37-2.2021.44-50.
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The purpose of the work. Investigation of the manifestations of rock pressure in the retractable road of a steep coal seam to ensure the operational state of production and increase the safety of work at the excavation site of a deep coal mine. The research used a comprehensive approach, including analysis and generalization of theoretical and experimental research on this problem, field experiment to study the stability of retractable drifts and processing of experimental data. To assess the stability of the preparatory workings, mine studies were performed to study the manifestations of rock pressure in the retractable drift under different methods of protection, when the magnitude of the displacement of lateral rocks on the contour and change the cross-sectional area of the drift along the excavation section. As a result of the performed researches the conditions of stability of retractable drifts of steep coal seams at protection by fires from wooden sleepers and bushes from risers are substantiated. It is recorded that in the zone of influence of mining works, the fastening in the retractable road is deformed and has characteristic curves from the roof. At a distance of l > 80 m behind the clearing face, the loss of the cross-sectional area of the excavation was about 50 % with the method of protection by bushes from the risers and 30 % with the use of wooden fires. It is experimentally proved that with the method of protection of precinct preparatory workings by rigid wooden structures in the form of bushes from risers, the change of cross-sectional area of the retractable lane behind the treatment face in the area of impact of treatment works occurs linearly with increasing length of the excavation site. To ensure the stability of retractable drifts in a deep coal mine with a steep occurrence of coal seams, it is advisable to use aimless methods of protection, when to support the side rocks are used pliable structures in the form of fires made of wooden sleepers. The use of this method of protection of the preparatory workings can reduce the likelihood of landslides and increase the safety of mining operations.
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Daly, Lisa Michelle. "An Empty Graveyard: The Victims of the 1946 AOA DC-4 Crash, Their Final Resting Place, and Dark Tourism." AP: Online Journal in Public Archaeology 8, no. 2 (October 12, 2018): 79. http://dx.doi.org/10.23914/ap.v8i2.166.
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In 2013, archaeologists succeeded in locating a plane crash that had been presumed buried based on local stories. The aircraft had crashed into a steep hill, subsequently known as Crash Hill. On the summit is a deteriorated memorial which resembles a cemetery, marking the thirty-nine people who died in the 1946 tragedy. This memorial has been a spot of pilgrimage for family and an attraction for adventure seekers. This draw to dark tourism sites is not uncommon but since archaeologists shared their finds with the public through social and local media, many of those visitors are drawn to the crash site instead of the memorial. This is a problem as there are possibly mass graves at the crash site, and visitation can potentially disturb those remains. This article argues for caution when discussing finds publically and for the repair and restoration of the memorial at the top of the hill to fill the want to visit a site of tragedy without disturbing the actual crash site.
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Katsidoniotaki, Eirini, Erik Nilsson, Anna Rutgersson, Jens Engström, and Malin Göteman. "Response of Point-Absorbing Wave Energy Conversion System in 50-Years Return Period Extreme Focused Waves." Journal of Marine Science and Engineering 9, no. 3 (March 22, 2021): 345. http://dx.doi.org/10.3390/jmse9030345.
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This work evaluates the survivability of a point-absorbing wave energy converter at sea states along and inside the 50-year environmental contour for a selected-site in North Sea, by utilizing CFD simulations. Focused wave groups based on NewWave theory are used to model the extreme waves. The numerical breaking waves have been previously predicted by the analytical breaking criterion, showing that the latter provides an accurate estimate for the breaking state. The forces on key components of the device and the system’s dynamics are studied and compared. Slamming loads are identified in the interaction with extreme waves, particularly with breaking waves, and compared with the analytical formulas for slamming estimation as suggested by industrial standards. Considering the extreme wave characteristics, the accompanied phenomena and the resulting WEC’s response, this work contributes to the identification of the design-waves given the environmental contour of the selected site. The top-left side of the contour is identified as the more critical area as it consists of steep and high waves inducing significant nonlinear phenomena, resulting in high loads.
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Orellana-Alvear, Johanna, Rolando Célleri, Rütger Rollenbeck, and Jörg Bendix. "Optimization of X-Band Radar Rainfall Retrieval in the Southern Andes of Ecuador Using a Random Forest Model." Remote Sensing 11, no. 14 (July 10, 2019): 1632. http://dx.doi.org/10.3390/rs11141632.
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Despite many efforts of the radar community, quantitative precipitation estimation (QPE) from weather radar data remains a challenging topic. The high resolution of X-band radar imagery in space and time comes with an intricate correction process of reflectivity. The steep and high mountain topography of the Andes enhances its complexity. This study aims to optimize the rainfall derivation of the highest X-band radar in the world (4450 m a.s.l.) by using a random forest (RF) model and single Plan Position Indicator (PPI) scans. The performance of the RF model was evaluated in comparison with the traditional step-wise approach by using both, the Marshall-Palmer and a site-specific Z–R relationship. Since rain gauge networks are frequently unevenly distributed and hardly available at real time in mountain regions, bias adjustment was neglected. Results showed an improvement in the step-wise approach by using the site-specific (instead of the Marshall-Palmer) Z–R relationship. However, both models highly underestimate the rainfall rate (correlation coefficient < 0.69; slope up to 12). Contrary, the RF model greatly outperformed the step-wise approach in all testing locations and on different rainfall events (correlation coefficient up to 0.83; slope = 1.04). The results are promising and unveil a different approach to overcome the high attenuation issues inherent to X-band radars.
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Etzold, S., N. Buchmann, and W. Eugster. "Contribution of advection to the carbon budget measured by eddy covariance at a steep mountain slope forest in Switzerland." Biogeosciences Discussions 7, no. 2 (March 3, 2010): 1633–73. http://dx.doi.org/10.5194/bgd-7-1633-2010.
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Abstract. We calculated the contribution of advection to the C budget measured by the eddy covariance (EC) technique for a steep and forested mountain site (CarboEurope site CH-Lae, Laegeren, Switzerland) during the growing season 2007 (May to August). Thereby we followed two approaches: (1) the physical correction of the EC data for directly measured advection terms and (2) the u∗ filter approach that replaces periods with u∗ below a site-specific threshold with empirically modelled fluxes. We found good agreement between the two approaches in terms of daily (linear regression slope: 0.77±0.04, intercept: 1.23±0.27 μmol m−2 s−1, adj. R2=0.80) and seasonal sums of gross fluxes (difference ≤12%), when using a u∗ threshold of 0.3 m s−1 and correcting EC for horizontal advection only. Incorporating also vertical advection into the mass balance equation resulted in unrealistic and highly erratic fluxes. However, on a daily basis vertical advection cancelled out to nearly zero. The u∗ filter seems to account primarily for respiration fluxes, which are mainly affected by horizontal advection. We could confirm our corrections by a cross-validation with independent approaches, such as soil respiration chamber measurements, light curves and energy budget closure. Our results show that flux measurements on steep sites with complex topography are possible. Actually, sloping sites seem to have the advantage over flat sites that advection measurements can be reduced to a simplified two-dimensional measurement approach due to the two-dimensional characteristics of the wind field at those sites.
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Etzold, S., N. Buchmann, and W. Eugster. "Contribution of advection to the carbon budget measured by eddy covariance at a steep mountain slope forest in Switzerland." Biogeosciences 7, no. 8 (August 17, 2010): 2461–75. http://dx.doi.org/10.5194/bg-7-2461-2010.
Full textAbstract:
Abstract. We calculated the contribution of advection to the C budget measured by the eddy covariance (EC) technique for a steep and forested mountain site (CarboEurope site CH-Lae, Lägeren, Switzerland) during the growing season 2007 (May to August). Thereby we followed two approaches: (1) the physical correction of the EC data for directly measured advection terms and (2) the u∗ filter approach that replaces periods with u∗ below a site-specific threshold with empirically modelled fluxes. We found good agreement between the two approaches in terms of daily (linear regression slope: 0.78 ± 0.04, intercept: 0.68 ± 0.29 μmol m−2 s−1, adj. R2=0.78) and seasonal sums of gross fluxes (difference ≤ 12%), when using a u∗ threshold of 0.3 m s−1 and correcting EC for horizontal advection only. Incorporating also vertical advection into the mass balance equation resulted in unrealistic and highly erratic fluxes. However, on a daily basis vertical advection cancelled out to nearly zero. The u∗ filter seems to account primarily for respiration fluxes, which are mainly affected by horizontal advection. We could confirm our corrections by a cross-validation with independent approaches, such as soil respiration chamber measurements, light curves and energy budget closure. Our results show that flux measurements on steep sites with complex topography are possible. Actually, sloping sites seem to have the advantage over flat sites that advection measurements can be reduced to a simplified two-dimensional measurement approach due to the two-dimensional characteristics of the wind field at those sites.
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Strub, Larissa, Manfred Stoll, and Simone Mueller Loose. "The effects of low-input training systems on viticultural costs on flat terrain and steep slope sites." OENO One 55, no. 2 (June 28, 2021): 415–29. http://dx.doi.org/10.20870/oeno-one.2021.55.2.4619.
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Low-input training systems, such as minimal pruning (MP) and the semi-minimal pruned hedge (SMPH), require less working hours as a result of fewer viticultural process steps and permit a higher degree of mechanisation. However, their effect on viticultural costs and per litre costs on both flat terrain and steep slopes has not yet been analysed. This study quantifies the viticultural costs of vertical shoot positioning (VSP) and low-input training systems for standard processes on different types of flat terrain and steep slope vineyards. The costs were obtained from a dataset of 1,519 working time records of labour and machine hours from 20 vineyards belonging to five German wine estates over three years. The costs for standard viticultural processes were compared across three pairs of VSP and low-input training site types with different mechanisation intensities. The comparison was carried out by univariate analysis of variance with fixed and random effects, and by descriptive analysis of mean values.On flat terrain, SMPH significantly decreased the costs for the viticultural steps of winter pruning, tying, shoot positioning and defoliation, but it increased the cost for pest control. Hence, the total cost on flat terrain decreased marginally, but still significantly, by 46 %. The cost effects on steep slopes were similar, decreasing by 34 % for SMPH in unsupported steep slope harvester sites and by 46 % for MP rope and winch-supported steep slope sites. The per-litre costs were calculated for different yield levels. Since the yield in low input systems is higher than in VSP, the production costs per litre further decreased.The study confirmed the high cost-saving potential for wine growers of the mechanisation of canopy management and the omission of winter pruning in low-input systems. Combined with higher yields, the cost savings from low-input systems are particularly suitable for producers of bulk wine and market entry and mid-level wine profiles. By converting to low-input systems, the costs associated with mechanisable steep slope vineyards can be reduced to amounts approximating VSP on flat terrain. For certain wine profiles, low-input systems should therefore constitute an integral part of strategies to increase the economic sustainability of steep slope viticulture. The estimated cost benchmarks provide critical input for the cost-based pricing policy of steep slope growers. These benchmarks also give agricultural policy reliable indicators of the subsidies required for preserving steep slope landscapes.
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Sobota, Daniel J., Stanley V. Gregory, and John Van Sickle. "Riparian tree fall directionality and modeling large wood recruitment to streams." Canadian Journal of Forest Research 36, no. 5 (May 1, 2006): 1243–54. http://dx.doi.org/10.1139/x06-022.
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Directionality of tree fall in riparian forests can strongly influence predictions of large wood recruitment to streams, yet accuracy of this model parameter has rarely been assessed with field data. We measured fall directions of 1202 riparian trees distributed among 21 stream sites across the Pacific Northwest, USA. Fall directions were oriented towards the stream at 16 sites, upstream at four sites, and not distinguishable from random at one site. Average tree fall direction across sites was correlated with valley constraint (Spearman r = 0.53; p = 0.02), but variability of fall directions was not correlated with this variable. When grouped by species (six conifers and one deciduous), individual trees exhibited stronger tendency to have fallen towards the channel on steep hillslopes (>40%) than on moderately sloped landforms (<40%). Integration of field data into an established recruitment model indicated that 1.5 to 2.4 times more large wood (by number of tree boles) would be recruited to stream reaches with steep hillslopes than to reaches with moderate side slopes or flat banks, if riparian forest conditions are assumed to be constant. We conclude that stream valley topography should be considered in models that use tree fall directions in predictions of large wood recruitment to streams.
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Konjar, Špela, Miha Pavšič, and Marc Veldhoen. "Regulation of Oxygen Homeostasis at the Intestinal Epithelial Barrier Site." International Journal of Molecular Sciences 22, no. 17 (August 25, 2021): 9170. http://dx.doi.org/10.3390/ijms22179170.
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The unique biology of the intestinal epithelial barrier is linked to a low baseline oxygen pressure (pO2), characterised by a high rate of metabolites circulating through the intestinal blood and the presence of a steep oxygen gradient across the epithelial surface. These characteristics require tight regulation of oxygen homeostasis, achieved in part by hypoxia-inducible factor (HIF)-dependent signalling. Furthermore, intestinal epithelial cells (IEC) possess metabolic identities that are reflected in changes in mitochondrial function. In recent years, it has become widely accepted that oxygen metabolism is key to homeostasis at the mucosae. In addition, the gut has a vast and diverse microbial population, the microbiota. Microbiome–gut communication represents a dynamic exchange of mediators produced by bacterial and intestinal metabolism. The microbiome contributes to the maintenance of the hypoxic environment, which is critical for nutrient absorption, intestinal barrier function, and innate and/or adaptive immune responses in the gastrointestinal tract. In this review, we focus on oxygen homeostasis at the epithelial barrier site, how it is regulated by hypoxia and the microbiome, and how oxygen homeostasis at the epithelium is regulated in health and disease.
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Rostovceva, J. I., A. N. Stafeev, T. V. Sukhanova, I. V. Latysheva, and V. L. Kosorukov. "Upper Bajocian of the Crimean Mountains: Paleogeography and sedimentary conditions based on palynological data." Moscow University Bulletin. Series 4. Geology, no. 3 (June 28, 2016): 3–10. http://dx.doi.org/10.33623/0579-9406-2016-3-3-10.
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The reconstruction of the sedimentation conditions and insular land landscapes on the site of modern Crimean Mountains for the Late Bajocian based on spore-pollen data, the mineral composition of clay rocks, textures and facies analysis and general paleogeographic analysis.It is shown that sublatitudinally elongated insular land had a width 30 km, the height not more than 1 km, steep northern slopes with mudflows and low-angle southern slopes with extensive river system.
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Mcclung, D. M., Simon Walker, and W. Gollen. "Characteristics of snow gliding on rock." Annals of Glaciology 19 (1994): 97–103. http://dx.doi.org/10.3189/1994aog19-1-97-103.
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Field measurements were made of snow gliding on steep, smooth rock slabs. Supporting dala included snowpack properties, snow rock interface temperatures, air temperatures and precipitation. In this paper, the temporal and spatial dependence of gliding is discussed from two seasons of measurements. The results showed that the basic temporal and spatial characteristics repeated from year to year at the site. The relationship of the measurements to snow-gliding constitutive relations and applications is briefly discussed.
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Mcclung, D. M., Simon Walker, and W. Gollen. "Characteristics of snow gliding on rock." Annals of Glaciology 19 (1994): 97–103. http://dx.doi.org/10.1017/s0260305500011046.
Full textAbstract:
Field measurements were made of snow gliding on steep, smooth rock slabs. Supporting dala included snowpack properties, snow rock interface temperatures, air temperatures and precipitation. In this paper, the temporal and spatial dependence of gliding is discussed from two seasons of measurements. The results showed that the basic temporal and spatial characteristics repeated from year to year at the site. The relationship of the measurements to snow-gliding constitutive relations and applications is briefly discussed.
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Shin, Hyeon-Gyu, Yanping Xu, and Zhe Lu. "Evidence for Sequential Ion-binding Loci along the Inner Pore of the IRK1 Inward-rectifier K+ Channel." Journal of General Physiology 126, no. 2 (July 25, 2005): 123–35. http://dx.doi.org/10.1085/jgp.200509296.
Full textAbstract:
Steep rectification in IRK1 (Kir2.1) inward-rectifier K+ channels reflects strong voltage dependence (valence of ∼5) of channel block by intracellular cationic blockers such as the polyamine spermine. The observed voltage dependence primarily results from displacement, by spermine, of up to five K+ ions across the narrow K+ selectivity filter, along which the transmembrane voltage drops steeply. Spermine first binds, with modest voltage dependence, at a shallow site where it encounters the innermost K+ ion and impedes conduction. From there, spermine can proceed to a deeper site, displacing several more K+ ions and thereby producing most of the observed voltage dependence. Since in the deeper blocked state the leading amine group of spermine reaches into the cavity region (internal to the selectivity filter) and interacts with residue D172, its trailing end is expected to be near M183. Here, we found that mutation M183A indeed affected the deeper blocked state, which supports the idea that spermine is located in the region lined by the M2 and not deep in the narrow K+ selectivity filter. As to the shallower site whose location has been unknown, we note that in the crystal structure of homologous GIRK1 (Kir3.1), four aromatic side chains of F255, one from each of the four subunits, constrict the intracellular end of the pore to ∼10 Å. For technical simplicity, we used tetraethylammonium (TEA) as an initial probe to test whether the corresponding residue in IRK1, F254, forms the shallower site. We found that replacing the aromatic side chain with an aliphatic one not only lowered TEA affinity of the shallower site ∼100-fold but also eliminated the associated voltage dependence and, furthermore, confirmed that similar effects occurred also for spermine. These results establish the evidence for physically separate, sequential ion-binding loci along the long inner pore of IRK1, and strongly suggest that the aromatic side chains of F254 underlie the likely innermost binding locus for both blocker and K+ ions in the cytoplasmic pore.
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Mellor, Greg J., Pankaj Panwar, Andrea K. Lee, Christian Steinberg, Julie A. Hathaway, Kirsten Bartels, Susan Christian, et al. "Type 8 long QT syndrome: pathogenic variants in CACNA1C-encoded Cav1.2 cluster in STAC protein binding site." EP Europace 21, no. 11 (August 13, 2019): 1725–32. http://dx.doi.org/10.1093/europace/euz215.
Full textAbstract:
Abstract Aims Pathogenic gain-of-function variants in CACAN1C cause type-8 long QT syndrome (LQT8). We sought to describe the electrocardiographic features in LQT8 and utilize molecular modelling to gain mechanistic insights into its genetic culprits. Methods and results Rare variants in CACNA1C were identified from genetic testing laboratories. Treating physicians provided clinical information. Variant pathogenicity was independently assessed according to recent guidelines. Pathogenic (P) and likely pathogenic (LP) variants were mapped onto a 3D modelled structure of the Cav1.2 protein. Nine P/LP variants, identified in 23 patients from 19 families with non-syndromic LQTS were identified. Six variants, found in 79% of families, clustered to a 4-residue section in the cytosolic II–III loop region which forms a region capable of binding STAC SH3 domains. Therefore, variants may affect binding of SH3-domain containing proteins. Arrhythmic events occurred in similar proportions of patients with II–III loop variants and with other P/LP variants (53% vs. 48%, P = 0.41) despite shorter QTc intervals (477 ± 31 ms vs. 515 ± 37 ms, P = 0.03). A history of sudden death was reported only in families with II–III loop variants (60% vs. 0%, P = 0.03). The predominant T-wave morphology was a late peaking T wave with a steep descending limb. Exercise testing demonstrated QTc prolongation on standing and at 4 min recovery after exercise. Conclusion The majority of P/LP variants in patients with CACNA1C-mediated LQT8 cluster in an SH3-binding domain of the cytosolic II–III loop. This represents a ‘mutation hotspot’ in LQT8. A late-peaking T wave with a steep descending limb and QT prolongation on exercise are commonly seen.
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Cvjeticanin, Rade, Olivera Kosanin, Marko Perovic, Milorad Janic, and Janko Ljubicic. "Ecological and floristic characteristics of new montpellier maple (Acer monspessulanum L.) site in the locality Glogovita kosa on Mt. Boranja." Bulletin of the Faculty of Forestry, no. 123 (2021): 33–54. http://dx.doi.org/10.2298/gsf2123033c.
Full textAbstract:
A new motpellier maple (Acer monspessulanum L.) site was described in this paper, located on mountain Boranja, in forest management unit ?Istocna Boranja?, above Roguljski potok, on Glogovita kosa ridge. Montpellier maple occurs on elevations between 460 and 480 m a.s.l., on southwestern and western aspect, on very steep slopes with inclination 45? t? 50?. The site area is 874 m2, ?nd coordinates of site centre are: ?=19?13?49.0? and ?=44?25?21.33?. In this site, Montpellier maple occurs in a plant community of hop-hornbeam and manna ash, and considering that Montpellier maple was recorded in all three layers, and that it occurs abundantly in shrub and ground layers, a subassotiation with montpellier maple was set apart (?stryo carpinifoliae-Fraxinetum orni subass. ?ceretosum monspessulanii). According to floristic composition, most plant species belong to the submediterranean floral type, so this community represents an enclave of submediterranean vegetation in the belt of continental beech forests. The community is of azonal character, orographically-edaphically conditioned, and occurs in warmer aspects, on shallow and skeletal rendzina on oolithic limestones.
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DÍAZ-RODRÍGUEZ, MIKEL, RAMÓN FÁBREGAS-VALCARCE, ARTURO DE LOMBERA-HERMIDA, and XOSÉ PEDRO RODRÍGUEZ-ÁLVAREZ. "ANÁLISIS LOCACIONAL DEL YACIMIENTO PALEOLÍTICO DE COVA EIRÓS (TRIACASTELA, LUGO)." Estudos do Quaternário / Quaternary Studies, no. 20 (December 31, 2021): 14–32. http://dx.doi.org/10.30893/eq.v0i20.199.
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In this paper, we deal with the locational analysis of the Cova Eirós site (Triacastela, Lugo), occupied from the Middle Palaeolithic to the present. From GIS and statistics, we intend to approach those environmental factors that define its importance as a place of occupation over time and on a recurring basis. Once we have analysed the variables that characterize the site’s patterns of use, we have verified that Cova Eirós is an important, prominent and strategic point. The place is very close to the potential transit routes and has great visibility. It is also protected and set on a steep slope. Moreover, the site has hunting resources and raw materials sources nearby. So it is a settlement that presents ideal living conditions for hunter-gatherer groups.
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Lee, Jaejoon, Hyunji Lee, Hongsik Yun, Chol Kang, and Moonsoo Song. "Improved Vulnerability Assessment Table for Retaining Walls and Embankments from a Working-Level Perspective in Korea." Sustainability 13, no. 3 (January 21, 2021): 1088. http://dx.doi.org/10.3390/su13031088.
Full textAbstract:
Climate change can lead to unpredictable slope collapse, which causes human casualties. Therefore, Korea has devoted significant effort to the management of slope disasters. The Ministry of the Interior and Safety of Korea, which oversees the safety of the nation’s people, has allocated a four-year budget of $557 million to investigate, assess, and maintain steep slope sites. However, there have been fatalities caused by steep slope site evaluations based on inadequate knowledge and a single retaining walls and embankments (RW&E) assessment table. Therefore, the assessment table for RW&E-type steep slopes needs to be improved in terms of its accuracy, simplicity, and ease of use. In this study, domestic and global evaluation methods were reviewed, problems associated with the existing RW&E assessment table were identified, and a focus group interview was conducted. The RW&E assessment table was improved through an indicator feasibility survey and analytic hierarchy processing. The improved assessment table was categorized from one to four classifications to reduce the ambiguity of the evaluation: concrete, reinforced soil-retaining walls, stone embankments, and gabions. This study will provide the sustainability of slope safety and serve as a reference for classification and evaluation criteria across all national institutions that conduct RW&E evaluations.
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Verbeek, H., and JM Cornelisse. "Consolidation of dredged sludge, measured by an acoustic densitometer." Marine and Freshwater Research 46, no. 1 (1995): 179. http://dx.doi.org/10.1071/mf9950179.
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A field study was conducted on the Cromstrijen dump site in the Rhine-Meuse estuary to find the risks of open-water dumping by estimating the impact effects and spreading of freshly deposited sludge and the consolidation of dumped material. The site is used to dump sludge of acceptable quality from maintenance dredging of waterways and local harbours. The investigated sludge came from a navigation channel and was dredged and transported by a hopper dredge. On the dump site, a small section was marked in which the dump took place. A field version of an existing laboratory acoustic densitometer was used to take a profile of the dry-weight concentration of the sediment bed as measured by the attenuation of high-frequency sound waves. The instrument was calibrated with the aid of homogenized field samples. The acoustic densitometer was useful for obtaining a profile of the bed density. With an echo-sounder, an attempt was made to evaluate the consolidation of the dumped sludge. The use of side-scan sonar at the dump site showed a crater with steep banks, surrounded by a thin layer of excess sediment extending over 8400 m². This was only 20% of the dumped sludge; the remaining material was transported outside the measurement section as a density current owing to near-bed surge and local bed slope. The results of the field study are compared with those of previous work and with estimates of the rate and area of distortion derived from theoretical models for the movement of a flow with negative buoyancy.