Journal articles: 'Horizontal Bores'

1

Haghi, Kevin R., David B. Parsons, and Alan Shapiro. "Bores Observed during IHOP_2002: The Relationship of Bores to the Nocturnal Environment." Monthly Weather Review 145, no. 10 (October 2017): 3929–46. http://dx.doi.org/10.1175/mwr-d-16-0415.1.

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This study documents atmospheric bores and other convergent boundaries in the southern Great Plains’ nocturnal environment during the IHOP_2002 summer campaign. Observational evidence demonstrates that convective outflows routinely generate bores. Statistically resampled flow regimes, derived from an adaptation of hydraulic theory, agree well with observations. Specifically, convective outflows within the observed environments are likely to produce a partially blocked flow regime, which is a favorable condition for generating a bore. Once a bore develops, the direction of movement generally follows the orientation of the bulk shear vector between the nose of the nocturnal low-level jet and a height of 1.5 or 2.5 km AGL. This relationship is believed to be a consequence of wave trapping through the curvature of the horizontal wind with respect to height. This conclusion comes after analyzing the profile of the Scorer parameter. Overall, these findings provide an impetus for future investigations aimed at understanding and predicting nocturnal deep convection over this region.

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Liu, Wei Kai, Ming Xing Song, Zi Yi Xu, and Xue Hong Zhang. "The Analysis of Horizontal Extension Capability in Horizontal Wells." Advanced Materials Research 1010-1012 (August 2014): 1745–49. http://dx.doi.org/10.4028/www.scientific.net/amr.1010-1012.1745.

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It is critical to understand whether the available drilling assembly could meet the requirements of drilling design during the design and drilling of horizontal wells. This paper pointed out several limitations on horizontal extension capability of horizontal wells and provided judging criteria of the limit of horizontal extension based upon the characteristics of horizontal wells, and set up the gap element model analyzing torque and dragged of whole drill strings in horizontal wells. According to the force analysis of drill strings in bores given the foundation for regularities in the distribution of torque and drag force along the axis, on the basis of those above mentioned models and theories, a software was made to calculate the torque and drag force of a well, which compared with the field data, the average discrepancies of theoretical values are below 20% that could meet the needs in field works.

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Rocheleau, D. N., and D. W. Dareing. "Effect of Drag Forces on Bit Weight in High-Curvature Well Bores." Journal of Energy Resources Technology 114, no. 3 (September 1, 1992): 175–80. http://dx.doi.org/10.1115/1.2905938.

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This paper gives a method of analysis for determining drill string weight required to develop a given bit force while drilling through and out of high-curvature well bores. The analysis is directed at medium radius well bores having radii of curvature ranging between 286 ft (87 m) and 955 ft (291 m), which are typically found in horizontal drilling. Sample calculations show how friction within the angle building portion of the well affect bit force.

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Shugan, Igor, Hwung-Hweng Hwung, and Ray-Yeng Yang. "TSUNAMI RUN-UP ON THE HORIZONTAL BEACH." Coastal Engineering Proceedings 1, no. 32 (January 23, 2011): 10. http://dx.doi.org/10.9753/icce.v32.currents.10.

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Tsunami run-up on the flat horizontal beach is studied by using the Benney shallow water equations. The dam-breaking flow includes vortexes, vertical shear flow and dissipation of momentum and energy on the front due to bore breaking. Propagating of hydrodynamics bores with breaking is analyzed by the mass, momentum and energy relations on the shock wave. Non dissipative wave front propagates faster than classical bore, while taking into account the dissipation and wave breaking leads to slowing of the wave front.

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Lin, Chang, Ming-Jer Kao, Juan-Ming Yuan, Rajkumar Venkatesh Raikar, Shih-Chun Hsieh, Po-Yu Chuang, Jie-Ming Syu, and Wei-Chih Pan. "Similarities in the free-surface elevations and horizontal velocities of undular bores propagating over a horizontal bed." Physics of Fluids 32, no. 6 (June 1, 2020): 063605. http://dx.doi.org/10.1063/5.0010321.

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6

Johnson, Aaron, and Xuguang Wang. "Multicase Assessment of the Impacts of Horizontal and Vertical Grid Spacing, and Turbulence Closure Model, on Subkilometer-Scale Simulations of Atmospheric Bores during PECAN." Monthly Weather Review 147, no. 5 (April 17, 2019): 1533–55. http://dx.doi.org/10.1175/mwr-d-18-0322.1.

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Abstract Four case studies from the Plains Elevated Convection at Night (PECAN) field experiment are used to investigate the impacts of horizontal and vertical resolution, and vertical mixing parameterization, on predictions of bore structure and upscale impacts of bores on their mesoscale environment. The reduction of environmental convective inhibition (CIN) created by the bore is particularly emphasized. Simulations are run with horizontal grid spacings ranging from 250 to 1000 m, as well as 50 m for one case study, different vertical level configurations, and different closure models for the vertical turbulent mixing at 250-m horizontal resolution. The 11 July case study was evaluated in greatest detail because it was the best observed case and has been the focus of a previous study. For this case, it is found that 250-m grid spacing improves upon 1-km grid spacing, LES configuration provides further improvement, and enhanced low-level vertical resolution also provides further improvement in terms of qualitative agreement between simulated and observed bore structure. Reducing LES grid spacing further to 50 m provided very little additional advantage. Only the LES experiments properly resolved the upscale influence of reduced low-level CIN. Expanding on the 11 July case study, three other cases from PECAN with diverse observed bore structures were also evaluated. Similar to the 11 July case, enhancing the horizontal and vertical grid spacings, and using the LES closure model for vertical turbulent mixing, all contributed to improved simulations of both the bores themselves and the larger-scale modification of CIN to varying degrees on different cases.

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Suzuki, Tomohiro, Toon Verwaest, William Veale, Koen Trouw, and Marcel Zijlema. "A NUMERICAL STUDY ON THE EFFECT OF BEACH NOURISHMENT ON WAVE OVERTOPPING IN SHALLOW FORESHORES." Coastal Engineering Proceedings 1, no. 33 (October 25, 2012): 50. http://dx.doi.org/10.9753/icce.v33.waves.50.

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In this paper, the effect of beach nourishment on wave overtopping in shallow foreshores is investigated with the non-hydrostatic wave-flow model SWASH. Firstly, the applicability of SWASH to model wave overtopping is tested by comparing results with a physical model setup with different storm wall heights on top of an impermeable sea dike. The numerical results show good agreement with the physical model. After validation, sensitivity analysis of the effect of beach nourishment on wave overtopping is conducted by changing bottom configurations with the SWASH model. From the sensitivity analysis, it becomes clear that wave overtopping discharge in shallow foreshores is characterized by the bores generated in surf zone due to wave breaking. To reduce wave overtopping discharge in shallow foreshore, it is important to reduce the horizontal momentum of the bores.

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8

Lutzak, Philip A. "A Proposal for Analyzing and Forecasting Lower-Atmospheric Undular Bores in the Western Gulf of Mexico Region." Weather and Forecasting 28, no. 1 (February 1, 2013): 55–76. http://dx.doi.org/10.1175/waf-d-12-00051.1.

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Abstract A method is presented for analyzing and forecasting the occurrence of lower-atmospheric undular bores over the western and central Gulf of Mexico (GOM) and adjacent land areas using standard operational forecasting and analysis techniques. The method is based on research that has identified a set of sufficient conditions associated with these occurrences realized by observations of the phenomena in recent years and is grounded in the theoretical understanding of undular bores developed during the last century by fluid dynamicists. The approach discusses practical approximations to the theory that allows the operational forecaster to use output from standard numerical and statistical forecast models. In addition to providing an operational method for forecasting the time and location of occurrence, the technique provides a methodology for analyzing and anticipating the strength, forward speed, and horizontal wavelength of the phenomena.

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9

Dareing, D. W., and C. A. Ahlers. "Tubular Bending and Pull-Out Forces in High-Curvature Well Bores." Journal of Energy Resources Technology 113, no. 2 (June 1, 1991): 133–39. http://dx.doi.org/10.1115/1.2905787.

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This paper is concerned with drag forces developed on tubulars in high-curvature well bores typically found in drainhole and horizontal drilling. The dog-leg severity of these types of boreholes are considerably higher than those typically found in conventional directional drilling. The objective of the study was to determine the significance of bending stiffness on drag forces in the pull-out mode. The method of analysis treats the tubular as a multi-spanned curved beam under tension and solves for radial displacements, slope, shear and bending moment over each span. Calculations show that bending stiffness is a minor factor provided there are no locally severe dog legs superimposed in the high-curvature well bore.

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10

Ostapenko, V. V. "On the application of the Green‒Nagdi equations for the simulation of wave flows with undular bores." Доклады Академии наук 484, no. 4 (May 5, 2019): 426–30. http://dx.doi.org/10.31857/s0869-56524844426-430.

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The basic conservation laws in the Green–Nagdi model of shallow-water theory are derived from the two-dimensional integral conservation laws of mass and the total momentum describing the plane-parallel flow in an ideal incompressible fluid above a horizontal bottom. This conclusion is based on the concept of a local hydrostatic approximation, which generalizes the concept of the long-wavelength approximation and is used for analyzing the applicability of the Green–Nagdi equations in modeling the wave flows with undular bores.

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11

Rajaie, Marieh, Amir H. Azimi, Ioan Nistor, and Colin D. Rennie. "TURBULENT BORES-INDUCED SCOUR AND PORE PRESSURE VARIATION AROUND A VERTICAL STRUCTURE." Coastal Engineering Proceedings, no. 36v (December 28, 2020): 29. http://dx.doi.org/10.9753/icce.v36v.sediment.29.

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Pore pressure and scour formation around coastal structures have been investigated in the past which led to a relationship between the hydrodynamics of tsunami waves and sediment erosion around coastal structures. With the objective of developing a comprehensive model to assess the interaction of hydrodynamic conditions, induced scour, soil pore pressure, and beach slopes, this novel study aims to examine (1) the effect of hydrodynamic forcing factors such as bore depth on scour and pore pressure generation on both horizontal and inclined bed conditions and (2) the effect of bed slope on the scour and pore pressure development and (3) the influence of the soil pore pressure on scour around a square shaped structure.Recorded Presentation from the vICCE (YouTube Link): https://youtu.be/dTQ-_GLhtzs

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12

Elsheikh, Nuri, Amir H. Azimi, Ioan Nistor, and Abdolmajid Mohammadian. "Tsunami-Induced Bores Propagating over a Canal, Part II: Numerical Experiments Using the Standard k-ε Turbulence Model." Fluids 7, no. 7 (June 22, 2022): 214. http://dx.doi.org/10.3390/fluids7070214.

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This companion paper presents the results of a series of numerical experiments examining the effects of a mitigation canal on the hydrodynamics of a tsunami-like turbulent bore proceeding over a horizontal bed. The hydraulic bores were generated by a dam-break setup which employed impoundment depths of do = 0.20 m, 0.30 m, and 0.40 m. The bore propagated downstream of the impoundments in the flume and interacted with a canal with varying geometry located downstream. The bore then left the flume through a drain located further downstream of the canal. In this study, the effect of the canal depth on the specific momentum and specific energy of hydraulic bores passing over a rectangular canal is numerically studied. The canal width was kept constant, at w = 0.6 m, while the canal depths were varied as follows: d = 0.05 m, 0.10 m, and 0.15 m. The time history of mean flow energy during the bore’s passing over the mitigation canal indicates that the jet stream of the maximum mean flow energy is controlled by the canal depth. The time required to dissipate the jet stream of the maximum vorticity, the turbulent kinetic energy, and the energy dissipation rate all increased as the canal depth decreased. The effect of canal orientation on the bore hydrodynamics was also numerically investigated, and it was found that the impulsive momentum and specific energy reached the highest values for canal orientations of 45 and 60 degrees. For the same canal depth, the highest peak specific momentum occurred with the highest degree of canal orientation (θ = 60°).

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13

Hozumi, Yuta, Akinori Saito, Takeshi Sakanoi, Atsushi Yamazaki, and Keisuke Hosokawa. "Mesospheric bores at southern midlatitudes observed by ISS-IMAP/VISI: a first report of an undulating wave front." Atmospheric Chemistry and Physics 18, no. 22 (November 19, 2018): 16399–407. http://dx.doi.org/10.5194/acp-18-16399-2018.

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Abstract. Large-scale spatial structures of mesospheric bores were observed by the Visible and near-Infrared Spectral Imager (VISI) of the ISS-IMAP mission (Ionosphere, Mesosphere, upper Atmosphere and Plasmasphere mapping mission from the International Space Station) in the mesospheric O2 airglow at 762 nm wavelength. Two mesospheric bore events in southern midlatitudes are reported in this paper: one event at 48–54∘ S, 10–20∘ E on 9 July 2015 and the other event at 35–43∘ S, 24∘ W–1∘ E on 7 May 2013. For the first event, the temporal evolution of the mesospheric bore was investigated from the difference of two observations in consecutive passes. The estimated eastward speed of the bore is 100 m s−1. The number of trailing waves increased with a rate of 3.5 waves h−1. Anticlockwise rotation with a speed of 20∘ h−1 was also recognized. These parameters are similar to those reported by previous studies based on ground-based measurements, and the similarity supports the validity of VISI observation for mesospheric bores. For the second event, VISI captured a mesospheric bore with a large-scale and undulating wave front. The horizontal extent of the wave front was 2200 km. The long wave front undulated with a wavelength of 1000 km. The undulating wave front is a new feature of mesospheric bores revealed by the wide field of view of VISI. We suggest that nonuniform bore propagating speed due to inhomogeneous background ducting structure might be a cause of the undulation of the wave front. Temperature measurements from the Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) onboard the Thermosphere, Ionosphere, Mesosphere, Energetics and Dynamics (TIMED) satellite indicated that bores of both events were ducted in a temperature inversion layer.

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14

Qi, Dan, Honglan Zou, Yunhong Ding, Wei Luo, and Junzheng Yang. "Engineering Simulation Tests on Multiphase Flow in Middle- and High-Yield Slanted Well Bores." Energies 11, no. 10 (September 28, 2018): 2591. http://dx.doi.org/10.3390/en11102591.

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Previous multiphase pipe flow tests have mainly been conducted in horizontal and vertical pipes, with few tests conducted on multiphase pipe flow under different inclined angles. In this study, in light of mid–high yield and highly deviated wells in the Middle East and on the basis of existent multiphase flow pressure research on well bores, multiphase pipe flow tests were conducted under different inclined angles, liquid rates, and gas rates. A pressure prediction model based on Mukherjee model, but with new coefficients and higher accuracy for well bores in the study block, was obtained. It was verified that the newly built pressure drawdown prediction model tallies better with experimental data, with an error of only 11.3%. The effect of inclination, output, and gas rate on the flow pattern, liquid holdup, and friction in the course of multiphase flow were analyzed comprehensively, and six kinds of classical flow regime maps were verified with this model. The results showed that for annular and slug flow, the Mukherjee flow pattern map had a higher accuracy of 100% and 80–100%, respectively. For transition flow, Duns and Ros flow pattern map had a higher accuracy of 46–66%.

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15

Elsheikh, Nuri, Ioan Nistor, Amir H. Azimi, and Abdolmajid Mohammadian. "Tsunami-Induced Bore Propagating over a Canal—Part 1: Laboratory Experiments and Numerical Validation." Fluids 7, no. 7 (June 22, 2022): 213. http://dx.doi.org/10.3390/fluids7070213.

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This companion paper investigates the hydrodynamics of turbulent bores that propagate on a horizontal plane and have a striking resemblance to dam break waves and tsunami-like hydraulic bores. The focus of this paper is on the propagation of a turbulent bore over a mitigation canal using both laboratory experiments and numerical simulations. In the first part of this paper, the effects of canal depth on the time histories of wave height and velocity were experimentally investigated, and the experimental results were used for the validation of the numerical model. The rapid release of water from an impoundment reservoir at depths of do = 0.30 m and 0.40 m generated bores analogous to tsunami-induced inundations. The time histories of the wave heights and velocities were measured at 0.2 m upstream and at 0.2 m and 0.58 m downstream of the canal to study the energy dissipation effect of the mitigation canal. The recorded time series of the water surface levels and velocities were compared with simulation outputs, and good agreement was found between the experimental and numerical water surface profiles, with a Root Mean Square Error (RMSE) of less than 6.7% and a relative error of less than 8.4%. Three turbulence models, including the standard k-ε, Realizable k-ε, and RNG k-ε, were tested, and it was found that all these models performed well, with the standard k-ε model providing the highest accuracy. The velocity contour plots of the mitigation canal with different depths showed jet streams of different sizes in the shallow, medium-depth, and deep canals. The energy dissipation and air bubble entrainment of the bore as it plunged downward into the canal increased as the canal depth increased, and the jet stream of the maximum bore velocity decreased as the canal depth increased. It was found that the eye of the vortex created by the bore in the canal moved in the downstream direction and plunged downward in the middle of the canal, where it then began to separate into two smaller vortices.

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16

Riaz, Muhammad Zain Bin, Shu-Qing Yang, Muttucumaru Sivakumar, Keith Enever, Usman Khalil, and Nadeeka Sajeewani Miguntanna. "Performance Evaluation of Force Transducer for the Observation of Sediment Entrainment in Rapidly Varied Flows." Journal of Atmospheric and Oceanic Technology 39, no. 10 (October 2022): 1579–89. http://dx.doi.org/10.1175/jtech-d-21-0101.1.

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Abstract Direct measurement of forces within the rough bed layer have been limited by previous spatial-averaging shear force studies. A highly sensitive force transducer assembled with a target sphere was used to measure and record the instantaneous three-dimensional forces of sediment at incipient motion. In the current study, a laser Doppler anemometer, ultrasonic displacement meter, and a force transducer accompanied by video recordings were used to experimentally investigate the incipient motion of sediment. The developed experimental setup have the potential to resolve and improve fundamental classical hypotheses regarding the incipient sediment motion. Experiments conducted in a large recirculating flume verified that the force transducer detects instantaneous forces at incipient motion under varies hydrodynamic conditions. Depth time series, instantaneous horizontal, vertical, and lateral forces are presented for dam-break and tidal breaking bores. Evidence suggests that the uplift vertical force plays an important role in destabilizing and in the incipient motion of particles. A sudden decrease in horizontal force was observed in tidal breaking bore due to flow reversal; however, a rapid rise was observed due to initial impact of dam-break bore. Bore velocity seems to have a larger effect on dam-break force than bore height. Furthermore, lateral force has the least influence during tidal breaking bore, while sediment particles are subjected to additional lateral force during dam-break bore.

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17

De Rouck, Julien, Koen Van Doorslaer, Tom Versluys, Karunya Ramachandran, Stefan Schimmels, Matthias Kudella, and Koen Trouw. "FULL SCALE IMPACT TESTS OF AN OVERTOPPING BORE ON A VERTICAL WALL IN THE LARGE WAVE FLUME (GWK) IN HANNOVER." Coastal Engineering Proceedings 1, no. 33 (December 14, 2012): 62. http://dx.doi.org/10.9753/icce.v33.structures.62.

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To meet up with the requirements of the Flemish Government, the Belgian coastline needs a protection to a storm with a return period of 1000 years. At well-chosen locations, storm walls will be built, and for the structural design of these walls the impact loadings need to be known. Tests have been carried out at full scale in the Grosser Wellen Kanal, to determine the impact loads by overtopping bores. Wave overtopping over the crest of the dike occurs, and the overtopping bore progresses along the horizontal crest of the dike before impacting the storm wall. It is of major importance that such a wall can withstand the impacts. This paper describes the hydraulic process on the crest of the dike, expressed with parameters such as flow depth and flow velocity, and links them to the impact measured on the storm wall. Both pressures and forces are measured, and compared to each other.

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18

Flournoy, Matthew D., and Michael C. Coniglio. "Origins of Vorticity in a Simulated Tornadic Mesovortex Observed during PECAN on 6 July 2015." Monthly Weather Review 147, no. 1 (January 2019): 107–34. http://dx.doi.org/10.1175/mwr-d-18-0221.1.

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To better understand and forecast nocturnal thunderstorms and their hazards, an expansive network of fixed and mobile observing systems was deployed in the summer of 2015 for the Plains Elevated Convection at Night (PECAN) field experiment to observe low-level jets, convection initiation, bores, and mesoscale convective systems. On 5–6 July 2015, mobile radars and ground-based surface and upper-air profiling systems sampled a nocturnal, quasi-linear convective system (QLCS) over South Dakota. The QLCS produced several severe wind reports and an EF-0 tornado. The QLCS and its environment leading up to the mesovortex that produced this tornado were well observed by the PECAN observing network. In this study, observations from radiosondes, Doppler radars, and aircraft are assimilated into an ensemble analysis and forecasting system to analyze this event with a focus on the development of the observed tornadic mesovortex. All ensemble members simulated low-level mesovortices with one member in particular generating two mesovortices in a manner very similar to that observed. Forecasts from this member were analyzed to examine the processes increasing vertical vorticity during the development of the tornadic mesovortex. Cyclonic vertical vorticity was traced to three separate airstreams: the first from southerly inflow that was characterized by tilting of predominantly crosswise horizontal vorticity along the gust front, the second from the north that imported streamwise horizontal vorticity directly into the low-level updraft, and the third from a localized downdraft/rear-inflow jet in which the horizontal vorticity became streamwise during descent. The cyclonic vertical vorticity then intensified rapidly through intense stretching as the parcels entered the low-level updraft of the developing mesovortex.

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19

Vakhromeev, A. G., R. Kh Akchurin, S. A. Sverkunov, D. A. Malikov, V. G. Zalivin, S. A. Makarov, and N. N. Martynov. "Lowering of a tie-back casing string into big-extension horizontal well bores of multilateral wells in conditions of a differential sticking." Construction of Oil and Gas Wells on Land and Sea, no. 12 (2019): 22–27. http://dx.doi.org/10.30713/0130-3872-2019-12-22-27.

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20

Derzho, Oleg G. "Large internal solitary waves on a weak shear." Chaos: An Interdisciplinary Journal of Nonlinear Science 32, no. 6 (June 2022): 063130. http://dx.doi.org/10.1063/5.0078975.

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Large amplitude solitary internal waves of permanent form propagating in a stratified shallow fluid between the free surface and a horizontal bottom are described by the amplitude equation obtained by a regular asymptotic procedure, which incorporates a complicated nonlinearity and Korteweg–de Vries (KdV) dispersion. It is discussed how the structure of stratification and shear affects wave properties. The particular case of a constant buoyancy frequency and a quadratic polynomial for the ambient shear for the flow under free surface is considered in detail analytically. It is shown that for such profiles, the equation for the wave amplitude reduces to the mixed-modified KdV equation and finite amplitude waves obey it up to the breaking level. Rogue waves could appear in this case, and the condition for their generation is identified. More complicated shear profiles lead to higher-order nonlinearities, which produce the multiscaled pyramidal wave patterns, asymmetric bores, and various instabilities. Such wave structures are studied numerically. An analytical bore-like solution having both exponential and algebraic asymptotes is presented.

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Narayanan, Viswanathan Lakshmi, Satonori Nozawa, Shin-Ichiro Oyama, Ingrid Mann, Kazuo Shiokawa, Yuichi Otsuka, Norihito Saito, Satoshi Wada, Takuya D. Kawahara, and Toru Takahashi. "Formation of an additional density peak in the bottom side of the sodium layer associated with the passage of multiple mesospheric frontal systems." Atmospheric Chemistry and Physics 21, no. 4 (February 18, 2021): 2343–61. http://dx.doi.org/10.5194/acp-21-2343-2021.

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Abstract. We present a detailed investigation of the formation of an additional sodium density peak at altitudes of 79–85 km below the main peak of the sodium layer based on sodium lidar and airglow imager measurements made at Ramfjordmoen near Tromsø, Norway, on the night of 19 December 2014. The airglow imager observations of OH emissions revealed four passing frontal systems that resembled mesospheric bores, which typically occur in ducting regions of the upper mesosphere. For about 1.5 h, the lower-altitude sodium peak had densities similar to that of the main peak of the layer around 90 km. The lower-altitude sodium peak weakened and disappeared soon after the fourth front had passed. The fourth front had weakened in intensity by the time it approached the region of lidar beams and disappeared soon afterwards. The column-integrated sodium densities increased gradually during the formation of the lower-altitude sodium peak. Temperatures measured with the lidar indicate that there was a strong thermal duct structure between 87 and 93 km. Furthermore, the temperature was enhanced below 85 km. Horizontal wind magnitudes estimated from the lidar showed strong wind shears above 93 km. We conclude that the combination of an enhanced stability region due to the temperature profile and intense wind shears have provided ideal conditions for evolution of multiple mesospheric bores revealed as frontal systems in the OH images. The downward motion associated with the fronts appeared to have brought air rich in H and O from higher altitudes into the region below 85 km, wherein the temperature was also higher. Both factors would have liberated sodium atoms from the reservoir species and suppressed the reconversion of atomic sodium into reservoir species so that the lower-altitude sodium peak could form and the column abundance could increase. The presented observations also reveal the importance of mesospheric frontal systems in bringing about significant variation of minor species over shorter temporal intervals.

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Nugrahanto, Kuntadi, Ildrem Syafri, and Budi Muljana. "Depositional Environment of Deep-Water Fan Facies: A Case Study of the Middle Miocene Interval at the Kutei and North Makassar Basins." Jurnal Geologi dan Sumberdaya Mineral 22, no. 1 (April 5, 2021): 45. http://dx.doi.org/10.33332/jgsm.geologi.v22i1.574.

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Massive exploration effort in the study area was conducted in 1996-2014 when deep-water drilling campaign found significant oil and gas discoveries but yet to optimally reach the middle Miocene deep-water sandstone reservoirs. Outcrops, well bores and 2D-seismic data had been incorporated in this study. Datum age from several taxon indicators have been utilized to correlate and unify various markers across the study area into four key biostratigraphy markers: M40, M45, M50, and M65. These four markers are at that point tied to the 2D seismic data in the act of the main horizons in conducting the seismic stratigraphy analysis over the study area not reached by wells. Identifying candidate of sub-regional sequence boundaries onshore and offshore that correspond with relative sea-level drops are the main result of this study. These results were integrated to generate the deep-water fan facies of the middle Miocene's gross depositional environment (GDE) maps, which generally show prograding succession easterly in the various shelf-breaks shifting laterally. The angle of slope and the horizontal length of the shelf-to-slope breaks significantly change from the Middle to Late Miocene until Recent time.Keywords: GDE, deep-water fan, Middle Miocene, Kutei, North Makassar.

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LIU, PHILIP L. F., YONG SUNG PARK, and JAVIER L. LARA. "Long-wave-induced flows in an unsaturated permeable seabed." Journal of Fluid Mechanics 586 (August 14, 2007): 323–45. http://dx.doi.org/10.1017/s0022112007007057.

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We present both analytical and numerical solutions describing seepage flows in an unsaturated permeable seabed induced by transient long waves. The effects of compressibility of pore water in the seabed due to a small degree of unsaturation are considered in the investigation. To make the problem tractable analytically, we first focus our attention on situations where the horizontal scale of the seepage flow is much larger than the vertical scale. With this simplification the pore-water pressure in the soil column is governed by a one-dimensional diffusion equation with a specified pressure at the water–seabed interface and the no-flux condition at the bottom of the seabed. Analytical solutions for pore-water pressure and velocity are obtained for arbitrary transient waves. Special cases are studied for periodic waves, cnoidal waves, solitary waves and bores. Numerical solutions are also obtained by simultaneously solving the Navier–Stokes equations for water wave motions and the exact two-dimensional diffusion equation for seepage flows in the seabed. The analytical solutions are used to check the accuracy of the numerical methods. On the other hand, numerical solutions extend the applicability of the analytical solutions. The liquefaction potential in a permeable bed as well as the energy dissipation under various wave conditions are then discussed.

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Leichter, J. J., G. B. Deane, and M. D. Stokes. "Spatial and Temporal Variability of Internal Wave Forcing on a Coral Reef." Journal of Physical Oceanography 35, no. 11 (November 1, 2005): 1945–62. http://dx.doi.org/10.1175/jpo2808.1.

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Abstract The deployment of a dense spatial array of temperature sensors on a coral reef in the Florida Keys provided a unique view of the interaction of cool water incursions generated by internal waves with the three-dimensional reef bathymetry. Water temperature on the reef surface was sampled every 5 s at 100 points on a 100 m by 150 m grid with concomitant measurements of water column velocity and temperature from mid-May through mid-August 2003. Episodic incursions of cool, subsurface water were driven by periods of strong semidiurnal internal tide and higher-frequency internal wave activity. For every time step in the data record the mean profile of temperature as a function of depth is calculated with a 3-m vertical averaging length scale. Subtracting this mean profile from the raw record yields a within depth, horizontal temperature anomaly. Visualization through time of the anomaly mapped onto the measured reef bathymetry reveals episodic variability of thermal patchiness across the reef as well as persistent features associated with reef bathymetry. Variation in the nature of the cooling and resulting thermal heterogeneity among events and seasons suggests multiple modes of cool water incursion ranging from unbroken, tidal period internal waves to packets of higher-frequency, energetic, broken internal bores.

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Petreshin, Dmitriy, Viktor Khandozhko, Andrey Dubov, and German Dobrovolsky. "Improvement of horizontal borer control system." Science intensive technologies in mechanical engineering 2020, no. 7 (July 16, 2020): 41–48. http://dx.doi.org/10.30987/2223-4608-2020-7-41-48.

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The control system improvement of a machine-tool is considered. The necessity in control system updating is substantiated. There is shown a procedure for horizontal borer updating. A problem on adjustment of modern digital electrical feed drives is presented. A sample of electrical feed drive and NC device adjustment is presented.

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26

Frank, R., H. Zervogiannis, S. Christoulas, V. Papadopoulos, and N. Kalteziotis. "Comportement de pieux d'essais instrumentés sous charge horizontale." Canadian Geotechnical Journal 30, no. 1 (February 1, 1993): 1–11. http://dx.doi.org/10.1139/t93-001.

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This paper describes the behaviour of two test piles (one bored and postgrouted and one simply bored, both 31.7 m long and 0.75 m in diameter) subjected to horizontal loads. These full-scale pile tests were carried out for the actual design of the pile foundation of a pier of the Evripos cable-stayed bridge. This bridge will link the Euboea Island to mainland Greece. The two piles have already been subjected to bearing capacity tests under axial loadings. The inclinometer measurements, taken during the present tests, yielded, in particular, the deformed shape of the piles as well as the bending moments. Conclusions could be drawn for the final design of the pile foundation with respect to horizontal loadings. Furthermore, various calculation methods using p–y reaction curves for cohesionless soils have been checked: the Ménard pressuremeter method, the method of the American Petroleum Institute recommendations, and the Standard penetration test method of Christoulas. These pile tests show that simple measurements, taken on construction sites, can yield interesting results on the actual behaviour of horizontally loaded piles. Key words : pile, horizontal loading, full-scale test, horizontal loads, bending moment, subgrade reaction modulus, p–y curve, cohesionless soil, Standard penetration test, pressuremeter test.

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27

Chia-Hui, Tang, Chen Tsair-Rong, and Chang Ching-Feng. "Ram spindle tolerance compensation for horizontal borer." International Journal of Advanced Manufacturing Technology 65, no. 1-4 (May 8, 2012): 507–16. http://dx.doi.org/10.1007/s00170-012-4189-x.

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28

Istrati, Denis, Ian Buckle, Pedro Lomonaco, and Solomon Yim. "Deciphering the Tsunami Wave Impact and Associated Connection Forces in Open-Girder Coastal Bridges." Journal of Marine Science and Engineering 6, no. 4 (December 5, 2018): 148. http://dx.doi.org/10.3390/jmse6040148.

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In view of the widespread damage to coastal bridges during recent tsunamis (2004 Indian Ocean and 2011 in Japan) large-scale hydrodynamic experiments of tsunami wave impact on a bridge with open girders were conducted in the Large Wave Flume at Oregon State University. The main objective was to decipher the tsunami overtopping process and associated demand on the bridge and its structural components. As described in this paper, a comprehensive analysis of the experimental data revealed that: (a) tsunami bores introduce significant slamming forces, both horizontal (Fh) and uplift (Fv), during impact on the offshore girder and overhang; these can govern the uplift demand in connections; (b) maxFh and maxFv do not always occur at the same time and contrary to recommended practice the simultaneous application of maxFh and maxFv at the center of gravity of the deck does not yield conservative estimates of the uplift demand in individual connections; (c) the offshore connections have to withstand the largest percentage of the total induced deck uplift among all connections; this can reach 91% and 124% of maxFv for bearings and columns respectively, a finding that could explain the damage sustained by these connections and one that has not been recognized to date; (e) the generation of a significant overturning moment (OTM) at the initial impact when the slamming forces are maximized, which is the main reason for the increased uplift in the offshore connections; and (f) neither maxFv nor maxOTM coincide always with the maximum demand in each connection, suggesting the need to consider multiple combinations of forces with corresponding moments or with corresponding locations of application in order to identify the governing scenario for each structural component. In addition the paper presents “tsunami demand diagrams”, which are 2D envelopes of (Fh, Fv) and (OTM, Fv) and 3D envelopes of (Fh, Fv, OTM), as visual representations of the complex variation of the tsunami loading. Furthermore, the paper reveals the existence of a complex bridge inundation mechanism that consists of three uplift phases and one downward phase, with each phase maximizing the demand in different structural components. It then develops a new physics-based methodology consisting of three load cases, which can be used by practicing engineers for the tsunami design of bridge connections, steel bearings and columns. The findings in this paper suggest the need for a paradigm shift in the assessment of tsunami risk to coastal bridges to include not just the estimation of total tsunami load on a bridge but also the distribution of this load to individual structural components that are necessary for the survival of the bridge.

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29

Chaney, RC, KR Demars, AGF de Sousa Coutinho, F. Toco Emilio, JL de Almeida Garrett, and E. Tavares Cardoso. "Instrumentation of Bored Concrete Piles for Horizontal Load Tests." Geotechnical Testing Journal 23, no. 3 (2000): 327. http://dx.doi.org/10.1520/gtj11054j.

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30

Nicholls, M. E. "An investigation of how radiation may cause accelerated rates of tropical cyclogenesis and diurnal cycles of convective activity." Atmospheric Chemistry and Physics Discussions 15, no. 5 (March 4, 2015): 6125–205. http://dx.doi.org/10.5194/acpd-15-6125-2015.

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Abstract. Recent cloud-resolving numerical modeling results suggest that radiative forcing causes accelerated rates of tropical cyclogenesis and early intensification. Furthermore, observational studies of tropical cyclones have found that oscillations of the cloud canopy areal extent often occur that are clearly related to the solar diurnal cycle. A theory is put forward to explain these findings. The primary mechanism that seems responsible can be considered a refinement of the mechanism proposed by Gray and Jacobson (1977) to explain diurnal variations of oceanic tropical deep cumulus convection. It is hypothesized that differential radiative cooling or heating between a relatively cloud-free environment and a developing tropical disturbance generates circulations that can have very significant influences on convective activity in the core of the system. It is further suggested that there are benefits to understanding this mechanism by viewing it in terms of the lateral propagation of thermally driven gravity wave circulations, also known as buoyancy bores. Numerical model experiments indicate that mean environmental radiative cooling outside the cloud system is playing an important role in causing a significant horizontal differential radiative forcing and accelerating the rate of tropical cyclogenesis. As an expansive stratiform cloud layer forms aloft within a developing system the mean low level radiative cooling is reduced while at mid levels small warming occurs. During the daytime there is not a very large differential radiative forcing between the environment and the cloud system, but at nighttime when there is strong radiative clear sky cooling of the environment it becomes significant. Thermally driven circulations develop, characterized by relatively weak subsidence in the environment but much stronger upward motion in the cloud system. This upward motion leads to a cooling tendency and increased relative humidity. The increased relative humidity at night appears to be a major factor in enhancing convective activity thereby leading in the mean to an increased rate of genesis. It is postulated that the increased upward motion and relative humidity that occurs throughout a deep layer both aids in the triggering of convection, and in providing a more favorable local environment at mid-levels for maintenance of buoyancy in convective cells due to a reduction of the detrimental effects of dry air entrainment. Additionally, the day/night modulations of the environmental radiative forcing appear to play a major role in the diurnal cycles of convective activity in the cloud system. It is shown that the upward velocity tendencies in the system core produced by the radiative forcing are extremely weak when compared to those produced by latent heat release in convective towers, but nevertheless over the course of a night they appear capable of significantly influencing convective activity.

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31

Nicholls, M. E. "An investigation of how radiation may cause accelerated rates of tropical cyclogenesis and diurnal cycles of convective activity." Atmospheric Chemistry and Physics 15, no. 15 (August 13, 2015): 9003–29. http://dx.doi.org/10.5194/acp-15-9003-2015.

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Abstract. Recent cloud-resolving numerical modeling results suggest that radiative forcing causes accelerated rates of tropical cyclogenesis and early intensification. Furthermore, observational studies of tropical cyclones have found that oscillations of the cloud canopy areal extent often occur that are clearly related to the solar diurnal cycle. A theory is put forward to explain these findings. The primary mechanism that seems responsible can be considered a refinement of the mechanism proposed by Gray and Jacobson (1977) to explain diurnal variations of oceanic tropical deep cumulus convection. It is hypothesized that differential radiative cooling or heating between a relatively cloud-free environment and a developing tropical disturbance generates circulations that can have very significant influences on convective activity in the core of the system. It is further suggested that there are benefits to understanding this mechanism by viewing it in terms of the lateral propagation of thermally driven gravity wave circulations, also known as buoyancy bores. Numerical model experiments indicate that mean environmental radiative cooling outside the cloud system is playing an important role in causing a significant horizontal differential radiative forcing and accelerating the rate of tropical cyclogenesis. As an expansive stratiform cloud layer forms aloft within a developing system the mean low-level radiative cooling is reduced, while at mid levels small warming occurs. During the daytime there is not a very large differential radiative forcing between the environment and the cloud system, but at nighttime when there is strong radiative clear-sky cooling of the environment it becomes significant. Thermally driven circulations develop, characterized by relatively weak subsidence in the environment but much stronger upward motion in the cloud system. This upward motion leads to a cooling tendency and increased relative humidity. The increased relative humidity at night appears to be a major factor in enhancing convective activity, thereby leading in the mean to an increased rate of genesis. It is postulated that the increased upward motion and relative humidity that occur throughout a deep layer aid both in the triggering of convection and in providing a more favorable local environment at mid levels for maintenance of buoyancy in convective cells due to a reduction of the detrimental effects of dry air entrainment. Additionally, the day/night modulations of the environmental radiative forcing appear to play a major role in the diurnal cycles of convective activity in the cloud system. It is shown that the upward velocity tendencies in the system core produced by the radiative forcing are extremely weak when compared to those produced by latent heat release in convective towers, but nevertheless over the course of a night they appear capable of significantly influencing convective activity.

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32

Sastry, V. V. R. N., and G. G. Meyerhof. "Influence of installation method on the behaviour of rigid piles in clay subjected to moment and horizontal load." Canadian Geotechnical Journal 24, no. 1 (February 1, 1987): 145–49. http://dx.doi.org/10.1139/t87-013.

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The lateral soil pressure distribution, pile capacity, and displacements of instrumented single rigid bored piles subjected to pure moment and horizontal load have been investigated. The influence of method of pile installation on the above parameters is studied by comparing the behaviour of bored piles with that of jacked piles. It was concluded that the method of installation has practically no effect so far as the net lateral soil pressures and pile capacity are concerned, but the displacements may be up to three times larger for a bored pile than for a jacked pile under working loads. Key words: clay, horizontal load, installation, model test, moment, pile.

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33

Jefferies, M. G. "Determination of horizontal geostatic stress in clay with self-bored pressuremeter." Canadian Geotechnical Journal 25, no. 3 (August 1, 1988): 559–73. http://dx.doi.org/10.1139/t88-061.

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The Gibson–Anderson theory for interpretation of pressuremeter data in clay is extended to include the unloading part of the test for the particular circumstances that prevail with a self-bored pressuremeter (SBP). Incorporation of the extended theory in a computer-aided modelling procedure allows horizontal geostatic stress to be unambiguously determined from SBP data by image matching irrespective of imperfections in the self-boring process. The procedure is illustrated by example on a previously reported test carried out in Beaufort Shelf clay. Key words: clay, in situ tests, self-bored pressuremeter, K0.

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34

Mohamed Jais, Ismacahyadi Bagus, Diana Che Lat, and Daniel Buttinger. "PERFORMANCE EVALUATION OF THE HYBRID GEOBAGS AND PU FLATBED SYSTEM AS A SOFT GROUND IMPROVEMENT WORK." Malaysian Journal of Civil Engineering 34, no. 2 (July 27, 2022): 45–50. http://dx.doi.org/10.11113/mjce.v34.18612.

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Soft ground is commonly known as a problematic soil foundation, thus required a ground improvement work to be executed. research was carried out to evaluate the performance of the Hybrid Geobag PU flatbed as a proposed remedial work for the failed embankment founded on soft ground in Pulau Betong. Back-analysis of existing embankment was executed using PLAXIS 2D in order to investigate the failure mechanism of the existing embankment. The cause of the embankment failure is due to the excessive consolidation settlement which causes both vertical and horizontal displacements of the . Performance of the proposed remedial works was compared with the conventional design solution of bored pile embankment. Existing embankment has an extreme vertical displacement of 1.87m and horizontal displacement of 0.259m. With the Hybrid Geobag PU flatbed method, the vertical and horizontal displacement reduced to 0.879m and 0.098m respectively. The vertical and horizontal displacement further reduced to 0.099m and 0.030m respectively with bored pile method.

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35

Novoa, Fernando, Tomás Altamirano, and José Tomás Ibarra. "NIDIFICACIÓN DE AVES EN BARRANCOS DE BORDE DE CAMINO EN EL BOSQUE TEMPLADO DEL SUR DE CHILE." Ornitología Neotropical 32, no. 1 (July 8, 2021): 17–21. http://dx.doi.org/10.58843/ornneo.v32i1.603.

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Aunque la ecología reproductiva de varias especies de aves que utilizan cavidades en árboles ha sido estudiada, el uso de los ba-rrancos de bordes de camino ha recibido menos atención. Aquí presentamos información sobre 38 nidos que fueron localizados en 19 cavi-dades en barrancos de bordes de camino, donde nidificaron nueve especies de aves que habitan los bosques templados del sur de Chile. Realizamos una descripción de las características de las cavidades ocupadas, el tamaño de puesta y el éxito de la nidada. Las características de las cavidades (cm) se relacionaron de forma proporcional con las medidas corporales de las especies (cm) que utilizaron los barrancos para nidificar. El diámetro de entrada horizontal, junto con la profundidad horizontal, mostraron una relación positiva con la longitud de cuerpo, y la masa corporal mostró una relación positiva con la profundidad horizontal de las cavidades utilizadas para nidificar. El tamaño de puesta promedio para seis especies fue 2,3 (± 0,4) huevos y el 48% de los nidos fueron exitosos. Nuestros registros aportan nuevos conoci-mientos sobre la historia de vida de estas especies y discutimos la potencial importancia de los barrancos de bordes de camino como hábitat reproductivo en los ecosistemas templados del sur.

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36

Benoit, Julien, Paul R. Manger, Luke Norton, Vincent Fernandez, and Bruce S. Rubidge. "Synchrotron scanning reveals the palaeoneurology of the head-butting Moschops capensis (Therapsida, Dinocephalia)." PeerJ 5 (August 10, 2017): e3496. http://dx.doi.org/10.7717/peerj.3496.

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Dinocephalian therapsids are renowned for their massive, pachyostotic and ornamented skulls adapted for head-to-head fighting during intraspecific combat. Synchrotron scanning of the tapinocephalid Moschops capensis reveals, for the first time, numerous anatomical adaptations of the central nervous system related to this combative behaviour. Many neural structures (such as the brain, inner ear and ophthalmic branch of the trigeminal nerve) were completely enclosed and protected by bones, which is unusual for non-mammaliaform therapsids. The nearly complete ossification of the braincase enables precise determination of the brain cavity volume and encephalization quotient, which appears greater than expected for such a large and early herbivore. The practice of head butting is often associated with complex social behaviours and gregariousness in extant species, which are known to influence brain size evolution. Additionally, the plane of the lateral (horizontal) semicircular canal of the bony labyrinth is oriented nearly vertically if the skull is held horizontally, which suggests that the natural position of the head was inclined about 60–65°to the horizontal. This is consistent with the fighting position inferred from osteology, as well as ground-level browsing. Finally, the unusually large parietal tube may have been filled with thick conjunctive tissue to protect the delicate pineal eye from injury sustained during head butting.

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37

Xiao, Zhao Yun, Guo Xun Zhang, Wei Xu, and Zhong Ming Xue. "Numerical Analysis of the Influence of Vertical Load on the Horizontal Bearing Capacity of Single Pile." Advanced Materials Research 374-377 (October 2011): 1947–52. http://dx.doi.org/10.4028/www.scientific.net/amr.374-377.1947.

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It is a complicated progress of interaction between pile and soil when pile is under both vertical load and horizontal load. This paper analyzes the variation of stress, strain, deformation and deflection of the pile body by finite element numerical simulation of single bored concrete pile under vertical load together with horizontal load. Based on the existing research results, conclusions could be that the vertical load can increase horizontal bearing capacity of the pile in sandy soils, but horizontal bearing capacity of the pile in clayey soils is more complicated. Hope that the simulation can provide some references for the design of pile foundation.

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38

Houlsby, G. T. "Determination of horizontal geostatic stress in clay with self-bored pressuremeter: Discussion." Canadian Geotechnical Journal 26, no. 4 (November 1, 1989): 758–59. http://dx.doi.org/10.1139/t89-092.

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39

Jefferies, M. G. "Determination of horizontal geostatic stress in clay with self-bored pressuremeter: Reply." Canadian Geotechnical Journal 26, no. 4 (November 1, 1989): 760–63. http://dx.doi.org/10.1139/t89-093.

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40

Zhou, Xiao Jun, Qi Sheng, and Rui Guo. "Study on Vibration Displacement of Ground Building Caused by Construction of Shallowly Bored Tunnel with Drill and Blast Method." Advanced Materials Research 838-841 (November 2013): 1359–62. http://dx.doi.org/10.4028/www.scientific.net/amr.838-841.1359.

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A mathematical formula to calculate relative horizontal displacement of ground building due to blast vibration of surrounding rock for bored tunnel by drill and blast method is propounded on the basis of differential equation for dynamic vibration, and the mathematical expression is deduced by means of Laplace transforms. The main factors which influence the horizontal displacement of ground building subject to rock blasting are also discussed in the paper.

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41

Paszkiewicz, Adam. "On microscopic sets and Fubini Property in all directions." Mathematica Slovaca 68, no. 5 (October 25, 2018): 1041–48. http://dx.doi.org/10.1515/ms-2017-0165.

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AbstractFor theσ-ideal$\mathcal{N} $of nullsets andσ-ideal$\mathcal{M} $of microscopic sets, it was recently obtained that there exists a Borel set$E\subset\mathbb{R}^{2} $with the following property:$E_{x}\in\mathcal{M} $for any$x\in\mathbb{R} $and$\{y;E^{y}\notin\mathcal{N}\}\notin\mathcal{M} $, for vertical sections$E_{x}=\{y;(x,y)\in E\} $and horizontal sections$E^{y}=\{x;(x,y)\in E\} $for$E\subset\mathbb{R}^{2} $. Thus$(\mathcal{N},\mathcal{M}) $does not satisfy Fubini Property. In this paper we obtain such Borel setE, that$\{y;E^{y}\notin\mathcal{N}\}\notin\mathcal{M} $and all non-horizontal (in a natural sense) sections ofEare in$\mathcal{M} $. Other Fubini type properties, with conditions written for all directions are also discussed.

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42

Ikui, Akihiro, Masaharu Sudo, Isamu Sando, and Shuji Fujita. "Postnatal Change in Angle between the Tympanic Annulus and Surrounding Structures." Annals of Otology, Rhinology & Laryngology 106, no. 1 (January 1997): 33–36. http://dx.doi.org/10.1177/000348949710600106.

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Postnatal developmental relationships in human ears were studied by a computer-aided three-dimensional reconstruction and measurement method. We measured the angle, in reference to the horizontal plane, between the tympanic annulus, the oval window, and the internal auditory canal (IAC) in 20 normal temporal bones obtained from individuals between 1 day old and 76 years old. The horizontal plane was defined as the plane sloped 30° infero-anteriorly from the plane of the horizontal canal in each specimen. The plane of the tympanic annulus changed from a nearly horizontal orientation (34.2° from the horizontal plane) in neonates to a more vertical orientation (63.3° from the horizontal plane) in adults. The tympanic annulus and oval window planes remained at the same angle to each other (11.9° ± 5.1°) throughout postnatal development, as did the plane of the tympanic annulus and the LAC (68.6° ± 5.3°). These findings have implications for ear surgeons, especially those operating on young children.

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43

Zanfelice, Gabriela Beduschi, and Elena Brugioni. "O Índico, uma promessa de horizonte - Entrevista com João Paulo Borges Coelho." Via Atlântica, no. 38 (December 23, 2020): 437–69. http://dx.doi.org/10.11606/va.i38.166285.

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João Paulo Borges Coelho é professor, historiador e escritor moçambicano de grande destaque no âmbito das Literaturas Africanas em língua portuguesa. A seguinte entrevista a João Paulo Borges Coelho foi realizada em Oxford, em novembro de 2019, e posteriormente revista e editada em colaboração com Elena Brugioni. Motivada pelos objetivos de propor o Oceano Índico e a Literatura-Mundial como possíveis paradigmas críticos para o estudo das Literaturas Africanas e de analisar os contos de Índicos Indícios (Borges Coelho, 2005) como narrativas emblemáticas de imaginários transnacionais da contemporaneidade moçambicana, a entrevista aborda, entre outras, questões referentes às relações entre literatura e crítica literária, África e o mar, Moçambique e o Índico, bem como algumas reflexões do autor sobre narrativas históricas.

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44

Kleczek, K., K. Majewska, W. Makowski, and D. Michalik. "The effect of diet supplementation with propolis and bee pollen on the physicochemical properties and strength of tibial bones in broiler chickens." Archives Animal Breeding 55, no. 1 (October 10, 2012): 97–103. http://dx.doi.org/10.5194/aab-55-97-2012.

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Abstract. The objective of this study was to determine the effect of diet supplementation with propolis and bee pollen on selected physical, biomechanical and chemical properties of tibial bones in broiler chickens. The experimental materials comprised 384 Ross 308 chickens (four groups, three replications), divided into groups of males and females, and raised to 35 days of age. Control group 1 birds were fed a commercial diet throughout the experiment. Birds of three other experimental groups received for the first two weeks of rearing standard diets with a different content of propolis and/or bee pollen: group 2 – 0.025 % propolis, group 3 – 0.5 % bee pollen, group 4 – 0.5 % bee pollen and 0.025 % propolis. The following parameters of the tibia were determined: weight, length, mid-shaft circumference, vertical and horizontal external diameters, vertical and horizontal internal diameters. The geometric characteristics of the bones were determined based on the above measurements. Mid-shaft shear strength was measured using an Instron universal testing machine 4301 (Instron, Norwood, MA, USA). The crude ash, calcium (Ca) and phosphorus (P) content of the tibia was also determined. Higher values of geometric parameters were noted in the tibial bones of broilers fed a diet supplemented with a combination of propolis and bee pollen, in comparison with birds fed diets containing propolis or bee pollen administered alone. The shear strength values and physical properties of bones were similar in all groups.

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45

Otaola, Clara. "Actualistic Zooarchaeology in Central Western Argentina in Cave and Open Air Contexts." Ethnobiology Letters 5 (September 4, 2014): 94–103. http://dx.doi.org/10.14237/ebl.5.2014.227.

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Many cultural and natural processes form the archaeological record. Taphonomy, the study of the transition of organic matter from living contexts (the biosphere) to geological contexts (the lithosphere), aids in understanding how agents and processes affect skeletal remains in the archaeological record. In this paper the results of an actualistic taphonomic study on deposition of bones in open-air and cave contexts in the high elevation Andes Mountains are presented. Results indicate that within the first three months after deposition many bones are displaced or removed from sites and that the agents that act in each context are different. Horizontal displacement of bones from their deposited locations is limited in the cave context but is dominant in the open air site. Carnivores appear to be responsible for moving bones in open-air contexts, and rodents appear to displace bones vertically in the cave context. Such naturalistic experiments are important in particular areas of the world in which local taphonomic processes vary.

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46

Lauridsen, Halfdan, Birgit Fischer Hansen, Ingermarie Reintoft, Jean W. Keeling, and Inger Kjær. "Histological Investigation of the Palatine Bone in Prenatal Trisomy 21." Cleft Palate-Craniofacial Journal 38, no. 5 (September 2001): 492–97. http://dx.doi.org/10.1597/1545-1569_2001_038_0492_hiotpb_2.0.co_2.

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Objective: The purpose of the present study was to investigate the horizontal part of the palatine bone in palates from human fetuses with trisomy 21 to improve the phenotypic classification of the genotypic anomaly. Methods: Material from 23 human trisomy 21 fetuses was included in the study. The crown rump lengths of the fetuses ranged from 80 mm to 190 mm, corresponding to about 12 to 21 weeks of gestational age. The material was examined histologically. Results and Conclusions: Histological examination demonstrated four different palatal phenotypes on the basis of the development of the horizontal part of the palatine bone: type I, palatine bone complete; type II, the mesial region of the horizontal part of the palatine bone is lacking; type III, complete absence of the horizontal part of the palatine bone; and type IV, auxiliary bones in the region of the transpalatine suture. This finding shows that different types of malformations may occur in the horizontal part of the palatine bone in human trisomy 21 fetuses.

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47

Grimshaw, Roger, Dave Broutman, Brian Laughman, and Stephen D. Eckermann. "Solitary Waves and Undular Bores in a Mesosphere Duct." Journal of the Atmospheric Sciences 72, no. 11 (November 1, 2015): 4412–22. http://dx.doi.org/10.1175/jas-d-14-0351.1.

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Abstract Mesospheric bores have been observed and measured in the mesopause region near 100-km altitude, where they propagate horizontally along a duct of relatively strong density stratification. Here, a weakly nonlinear theory is developed for the description of these mesospheric bores. It extends previous theories by allowing internal gravity wave radiation from the duct into the surrounding stratified regions, which are formally assumed to be weakly stratified. The radiation away from the duct is expected to be important for bore energetics. The theory is compared with a numerical simulation of the full Navier–Stokes equations in the Boussinesq approximation. Two initial conditions are considered. The first is a solitary wave solution that would propagate without change of form if the region outside the duct were unstratified. The second is a sinusoid that evolves into an undular bore. The main conclusion is that, while solitary waves and undular bores decay by radiation from the duct, they can survive as significant structures over sufficiently long periods (~100 min) to be observable.

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48

Cheng, Yong Chun, Ji Zhong Zhao, Peng Zhang, Jing Lin Tao, and Ya Feng Gong. "Research on the Optimization Design of the Bridge Foundation Bored Piles." Advanced Materials Research 1030-1032 (September 2014): 851–54. http://dx.doi.org/10.4028/www.scientific.net/amr.1030-1032.851.

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This paper improves the method of calculating the vertical bearing capacity of bored piles, and unifies calculation method of singe pile under horizontal force, as well adds and modifies the design parameters of the specification, finally utilizes actual example to make a unified test of the above methods. The results proved that, through the optimization of bridge foundation design method of bored piles, it can significantly reduce construction cost, and makes the pile length, pile diameter, and reinforcement more safe and reasonable. At the same time, it has great directive significance to the design and construction of the bridge.

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49

Tawfik, Kareem O., Brittany A. Leader, Zoe A. Walters, and Daniel I. Choo. "Relative Preservation of Superior Semicircular Canal Architecture in CHARGE Syndrome." Otolaryngology–Head and Neck Surgery 160, no. 6 (January 22, 2019): 1095–100. http://dx.doi.org/10.1177/0194599818824306.

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Objectives (1) Describe common patterns of semicircular canal (SCC) anomalies in CHARGE syndrome (CS) and (2) recognize that in CS, the architecture of the superior SCC may be relatively preserved. Study Design This is a retrospective review of temporal bone imaging studies. Setting Quaternary care center. Subjects and Methods A sample of 37 patients with CS. All subjects met clinical diagnostic criteria for CS. The presence/absence of anomalies of the middle ear, mastoid, temporal bone venous anatomy, inner ear, and internal auditory canal was recorded. Anomalies of each SCC were considered separately and by severity (normal, dysplasia, aplasia). Results Thirty-seven subjects (74 temporal bones) were reviewed. Thirty-four (92.0%) patients demonstrated bilateral SCC anomalies. Three (8.0%) had normal SCCs. In patients with SCC anomalies, all canals demonstrated bilateral abnormalities. Thirty-two (86.5%) patients had bilateral horizontal SCC aplasia. These 32 patients also demonstrated posterior SCC aplasia in at least 1 ear. Of 74 temporal bones, 37 (50.0%) had superior SCC dysplasia. All dysplastic superior SCCs showed preservation of the anterior limb. Complete superior SCC aplasia was found in 28 (37.8%) temporal bones. Conclusion SCC anomalies occur with high frequency in CS. Complete absence of the horizontal and posterior canals is typical and usually bilateral. By contrast, the superior SCC often demonstrates relative preservation of the anterior limb.

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Gotman, Alfred, and Airat Gaisin. "STUDY OF THE LARGE-SCALE BORED PILES ON THE HORIZONTAL LOAD AND THEIR CALCULATION." PNRPU Construction and Architecture Bulletin 9, no. 3 (2018): 14–27. http://dx.doi.org/10.15593/2224-9826/2018.3.02.

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Journal articles on the topic 'Horizontal Bores'

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