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To solve the safety hazard of a buried gas pipeline caused by subsidence of a mined-out area, a three-dimensional model of a buried pipeline in a mined-out area was established using geological parameters and the finite-element software ABAQUS. The effects of the friction coefficient of the pipe and soil, the coal-seam dip angle, and the horizontal angle on the mechanical behavior of the pipe under varying widths of goaf area were investigated. The results indicate that the maximum equivalent stress of the pipeline is negatively correlated with the horizontal angle. Concerning longitudinal mining, the pipeline exhibits a high-stress zone when the mining length is >200 m, the surface displacement appears in a small range when the mining length is 40 m, and the stratum displacement range increases gradually with the increase in the mining length. When the width of the goaf is constant, the maximum equivalent stress of the pipeline is positively correlated with the tube-soil friction coefficient and negatively correlated with the coal seam dip angle. The position of maximum stress gradually tends to appear near the uphill side of the coal seam, with an increase in the coal seam dip angle.

Information about anisotropic resistivity is essential in real-time correlation, updating of formation model and making more confident geosteering decisions in logging-while-drilling (LWD) application. However, abnormal responses such as curve separations and apparent resistivity “horns” often exist in the LWD resistivity measurements due to the influences of complex downhole environments. Thus, accurate formation resistivity is not readily available. In this paper, we present an efficient inversion scheme for the rapid estimation of anisotropic resistivity from LWD resistivity measurements acquired in high-angle and horizontal wells. Several strategies are adopted in the inversion: (1) a one-dimensional (1D) simulator with a simplified three-layered model guarantees the forward speed and keeps the number of inverted parameters as few as possible; (2) combined with geological and petrophysical bounds, the tool constraints derived from a detection capability analysis of LWD resistivity measurements are applied to scale down the inverted parameters’ searching scope, which avoids meaningless solutions and accelerates the inversion significantly; (3) multiple-initial guesses are used in the inversion to ensure a global solution. Inversion results over synthetic examples demonstrate that the proposed 1D inversion algorithm is well suited for complex formation structures. It is also robust and fast in extracting anisotropic resistivities from LWD resistivity measurements.

With the growing demand for energy saving, emission reduction, and green metallurgy, we had designed a new C–H 2 smelting reduction reactor. In order to solve the key problem that the heat transfer efficiency from high temperature oxidation zone in upper region to low temperature reduction zone in lower region is low in traditional metallurgical reduction reactor, a water simulation was adopted to optimize the mean residence time and to improve the transmission efficiency within the reactor. According to the modified Froude similarity, a water model experimental reactor with a ratio of 1:1 to the prototype was constructed. In the prototype, the feed port was used to feed preheated ore and flux. In order to simulate the effect of different feeding positions of the tracer on the mixing behavior in the molten pool, four points of tracer feeding position were arranged for a systematic study. At the same time, based on double-row side nozzle with thick slag layer in a C–H 2 smelting reduction reactor, nine influencing factors, including relative angle between upper and lower side nozzles, were studied. The experimental results showed that the tracer feeding position had a great influence on the mean residence time, and the relative angle also had a great influence on tracer feeding position. Finally, through comprehensive analysis, the optimal condition parameters were obtained under different tracer feeding positions. These results provide valuable help for the design and optimization of the C-H 2 smelting reduction reactor.

Road horizontal curves, which significantly influence drivers’ visual search behavior and are closely linked to traffic safety, also constitute a crucial factor in sustainable road traffic development. This paper uses simulation driving experiments to explore the dynamic response characteristics of 27 typical subject drivers’ visual search behavior regarding road horizontal curve radius. Results show that in a monotonous, open road environment, the driver’s visual search is biased towards the inside of the curve; as the radius increases, the 85th percentile value of the longitudinal visual search length gradually increases, the 85th percentile value of the horizontal search angle gradually decreases, the 85th percentile value of vehicle speed gradually increases, and the dispersion and bias of the gaze points gradually decrease. The search length, horizontal angle, and speed approach the level of straight road sections (380 m, 10° and 115 km/h, respectively). When R ≥ 1200 m, a driver’s dynamic visual search range reaches a stable distribution state that is the same as that of a straight road. A dynamic visual search range distribution model for drivers on straight and horizontal curved road sections is constructed. Based on psychological knowledge such as attention resource theory and eye–mind theory, a human factor engineering explanation was provided for drivers’ attention distribution and speed selection mechanism on road horizontal curve sections. The research results can provide theoretical references for the optimization design of road traffic, decision support to improve the driver training system, and a theoretical basis for determining the visual search characteristics of human drivers in autonomous driving technology, thereby promoting the safe and sustainable development of road traffic.

According to the actual requirements, profile and rolling energy consumption are selected as objective functions of rolling schedule optimization for tandem cold rolling. Because of mechanical wear, roll diameter has some uncertainty during the rolling process, ignoring which will cause poor robustness of rolling schedule. In order to solve this problem, a robust multi-objective optimization model of rolling schedule for tandem cold rolling was established. A differential evolution algorithm based on the evolutionary direction was proposed. The algorithm calculated the horizontal angle of the vector, which was used to choose mutation vector. The chosen vector contained converging direction and it changed the random mutation operation in differential evolution algorithm. Efficiency of the proposed algorithm was verified by two benchmarks. Meanwhile, in order to ensure that delivery thicknesses have descending order like actual rolling schedule during evolution, a modified Latin Hypercube Sampling process was proposed. Finally, the proposed algorithm was applied to the model above. Results showed that profile was improved and rolling energy consumption was reduced compared with the actual rolling schedule. Meanwhile, robustness of solutions was ensured.

Energy dissipation is one of the most important factors in choosing stepped spillways. However, very few studies have investigated energy dissipation with different horizontal face angles. In this paper, the realizable k-ε turbulent model was used to study the flow field, energy dissipation rates and turbulent kinetic energy and its dissipation rate for different stepped spillways with five horizontal face angles in the skimming flow regions. Results showed that the field and direction of the flow were changed by the horizontal face angles of the stepped spillway, which produced some unique characteristics and thus caused better energy dissipation. The fluctuation of free water surface will be larger with increasing horizontal face angles and the energy dissipation rate decreases with an increasing unit discharge and increases for the enlargement of the horizontal face angles. This conclusion could provide a reference for the relevant research of V shaped stepped spillways.

The purpose of this study was to determine the effects of hammer rotation on performance in hammer throwing. The hammer's velocity increment at different stages, the duration of rotations at different phases, and the horizontal azimuth angle and rotation radius at critical instants were calculated and compared between the long and short trials for 26 female athletes in actual competitions. Compared to short trials, female throwers' long trials exhibited significantly larger release velocity ( < 0.001, ES = 1.42), greater velocity increment during the double support phase ( = 0.006, ES = 0.59), shorter duration during the single support phase ( ≤ 0.043, ES = 0.42-0.83), lower horizontal azimuth angle ( ≤ 0.027, ES = 0.46-0.57), and longer rotational radius at critical instants ( ≤ 0.021, ES = 0.48-0.73). During the process from the hammer head's low point to high point, athletes should focus on increasing the rotation radius of the hammer head and accelerating the right foot's landing speed during the single support phase. This approach aims to reduce the hammer's horizontal azimuth angle at the right foot touchdown, enhance the acceleration performance during the double support phase, and increase the release speed.

Liu, X.; Chen, X.; Liu, J.; Yu, T., and Sun, B., 2021. Scour effects on cyclic response of bucket foundations under waves and currents. Journal of Coastal Research, 37(3), 670–682. Coconut Creek (Florida), ISSN 0749-0208. The scour around the bucket foundation has a significant impact on the response and stability of the bucket foundation. A series of tests have been carried out to estimate the effect of scour on the cyclic response of the bucket foundation under waves and currents. It is found that the scour depth Sd/d of the bucket increases with the increase in Fra. The top displacement of the bucket increases with the increase of wave height and scour depth. When the wave force accounts for more than 90% of the wave flow force (0.05 < Fra < 0.5), at the same wave height, the scour depth can increase more than 0.6 d, the rotation angle can increase by 120–200%. This article proposes an empirical relationship with an error of 10–20% for evaluating the bucket foundation rotation angle under scour, which can provide a relevant reference for the design of the bucket foundation.

The collision of the Indian plate and the Eurasian plate created shortening and imbrications with thrusting and faulting which influences northward tectonic movement. This plate movement has divided the Himalaya into four parts, viz . Outer Himalaya, Lesser Himalaya, Greater Himalaya, and Tethys Himalaya. The crystalline basement rock plays an imperative role for structural and tectonic association. The study has been carried out near Rishikesh-Badrinath neighborhood in the northwestern part of the Himalayan girdle with multifarious tectonic set up with thrusted and faulted geological setting. In this study area, 3D Euler deconvolution, horizontal gradient analysis, tilt angle (TILT) and horizontal tilt angle (TDX) analysis have been carried out using gravity data to delineate the subsurface geology and heterogeneity in the northwestern part of Himalaya. The Euler depth solutions suggest the source depth of about 12 km and various derivative analyses suggest the trend of the delineation thrust-fault boundaries along with the dip and strike direction in the study area.

The study has been carried out in the transition zone of the Narmada-Son lineament (NSL) which is seismically active with various geological complexities, upwarp movement of the mantle material into the crust through fault, fractures lamination and upwelling. NSL is one of the most prominent lineaments in central India after the Himalaya in the Indian geology. The area of investigation extends from longitude 80.25°E to 81.50°E and latitude 23.50°N to 24.37°N in the central part of the Indian continent. Different types of subsurface geological formations viz. alluvial, Gondwana, Deccan traps, Vindhyan, Mahakoshal, Granite and Gneisses groups exist in this area with varying geological ages. In this study area tectonic movement and crustal variation have been taken place during the past time and which might be reason for the variation of magnetic field. Magnetic anomaly suggests that the area has been highly disturbed which causes the Narmada-Son lineament trending in the ENE-WSW direction. Magnetic anomaly variation has been taken place due to the lithological variations subject to the changes in the geological contacts like thrusts and faults in this area. Shallow and deeper sources have been distinguished using frequency domain analysis by applying different filters. To enhance the magnetic data, various types of derivatives to identify the source-edge locations of the causative source bodies. The present study carried out the interpretation using total horizontal derivative, tilt angle derivative, horizontal tilt angle derivative and Cos (θ) derivative map to get source-edge locations. The results derived from various derivatives of magnetic data have been compared with the basement depth solutions calculated from 3D Euler deconvolution. It is suggested that total horizontal derivative, tilt angle derivative and Cos (θ) derivative are the most useful tools for identifying the multiple source edge locations of the causative bodies in this tectonically active and transition zone area. As this area is highly prone to hydrocarbon bearing zone, hence, the integrated interpretation could reliably image various thrusts and faults boundaries and the source edge locations with dip and strike orientation along with the basement lineation in encouraging exploration for better understanding of the geo-scientific data.