Oil Pads Research Articles

Frozen no more, a case study of Arctic permafrost impacts of oil and gas withdrawal

Approximately 8100 km2 of Alaska are leased to the oil and gas industry for exploration and extraction. According to industry estimates, subsurface expansion from these leases could cover up to 130.2 km2 per pad. As industrial oil extraction activities increase across the thawing Alaskan permafrost, impacts on the permafrost environment will include rapid thaw, increased hydrological flux, and the release of climate warming greenhouse gases. Here, we use remote sensing and field observations to provide a first-order comparison of the direct impacts to the permafrost tundra from oil well pads, and the long-term consequences of a legacy oil pads on the warming North Slope of Alaska. We find that oil well pads on the permafrost accelerate permafrost degradation and persist despite remediation.

An improved white shark optimizer algorithm used to optimize the structural parameters of the oil pad in the hydrostatic bearing

Abstract An improved white shark optimizer (MWSO) algorithm has been proposed. The algorithm adopts an improved tent chaotic mapping strategy to enhance the diversity of the initial population of white sharks, introduces the balance pool strategy of the EO algorithm to improve the convergence speed and accuracy of the algorithm, applies adaptive t-distribution dynamic selection probability perturbation to the global optimal solution, and adjusts the exploration and development ability of the algorithm at different iteration periods. MWSO, WSO, and seven excellent metaheuristic algorithms are tested and compared on 23 classic test functions and the CEC2017 test suite, and two non-parametric tests, a Wilcoxon rank sum test with a significance level of 0.05 and Friedman test, are conducted. The statistical results indicate that the proposed MWSO is significantly superior to other algorithms. In addition, nine algorithms are applied for the first time to optimize the structural parameters of the oil sealing edge of oil pads in response to the issue of the bearing capacity of hydrostatic bearings. This not only further verified the superiority of MWSO, but also provided new ideas for the optimization of hydrostatic bearings.

Phytotherapeutic recommendations in medical guidelines for the treatment of gastroenterological diseases - a systematic review

Phytotherapeutics are gaining influence in the treatment of gastroenterological diseases. Their popularity and growing evidence of efficacy contribute to their integration into medical guidelines. A systematic screening identified recommended phytotherapeutic approaches. Based on current scientific data, some recommendations for the use of phytotherapeutic agents are given. For irritable bowel syndrome the use of peppermint oil is "strongly recommended", especially for pain and flatulence. Other phytotherapeutics such as STW-5, Tibetan Padma Lax or warm caraway oil pads have proven effective in alleviating symptoms. It is "recommended" to integrate them into the treatment concept. For chronic constipation, 30g of fiber per day is recommended. Best data exists for plantago psyllium with moderate evidence and chicory inulin. In case of ulcerative colitis, plantago psyllium as well as the combination of myrrh, chamomile flower extract, and coffee charcoal can be used as a complementary treatment in maintaining remission. There is also an "open recommendation" for curcumin for both, remission induction and maintenance. Some phytotherapeutic treatments (e.g., Artemisia absintium, Boswellia serata) show evidence of effectiveness for the treatment of Crohn's disease, but data are not yet sufficient for recommendations. Cannabis-based medicines can be considered for abdominal pain and clinically relevant appetite loss if standard therapy is ineffective or contraindicated, but they should not be used for acute inflammation in active Crohn's disease. Further recommendations for other gastroenterological diseases are discussed. The safety and tolerability of the phytotherapeutics were rated as predominantly "very good" to "acceptable". Some clear recommendations for the use of phytotherapeutics to treat gastroenterological diseases show their great potential. Due to their wide range of effects, phytotherapeutics can be used very well as a complement to conventional medicines in case of complex regulatory disorders. However, further methodologically well-conducted impact studies would be helpful in order to be able to make further recommendations.

MULTIPLE OIL PAD DETECTION USING DEEP LEARNING

Abstract. Deep learning (DL) algorithms are widely used in object detection such as roads, vehicles, buildings, etc., in aerial images. However, the object detection task is still considered challenging for detecting complex structures, oil pads are one such example: due to its shape, orientation, and background reflection. A recent study used Faster Region-based Convolutional Neural Network (FR-CNN) to detect a single oil pad from the center of the image of size 256 × 256. However, for real-time applications, it is necessary to detect multiple oil pads from aerial images irrespective of their orientation. In this study, FR-CNN was trained to detect multiple oil pads. We cropped images from high spatial resolution images to train the model containing multiple oil pads. The network was trained for 100 epochs using 164 training images and tested with 50 images under 3 different categories. with images containing: single oil pad, multiple oil pad and no oil pad. The model performance was evaluated using standard metrics: precision, recall, F1-score. The final model trained for multiple oil pad detection achieved a weighted average for 50 images precision of 0.67, recall of 0.80, and f1 score of 0.73. The 0.80 recall score indicates that 80% of the oil pads were able to identify from the given test set. The presence of instances in test images like cleared areas, rock structures, and sand patterns having high visual similarity with the target resulted in a low precision score.

Aromatherapy in Palliative Care: A Single-Institute Retrospective Analysis Evaluating the Effect of Lemon Oil Pads against Nausea and Vomiting in Advanced Cancer Patients.

Simple SummaryPalliative care aims to improve the quality of life for patients with serious illnesses by improving symptoms. Many patients with advanced diseases suffer from nausea and vomiting. In addition to evidenced-based treatments, patients with advanced diseases often seek for complementary and integrative therapies. Aromatherapy is commonly used to alleviate the various symptoms of palliative care patients and is well accepted by both patients and their caregivers. We retrospectively evaluated the efficacy of using lemon oil pads against nausea and vomiting in our palliative care unit and found a positive effect against nausea and vomiting in this patient group.Aromatherapy is regularly used in the University Hospital Krems’s palliative care unit. In a retrospective analysis, we investigated whether there were improvements in nausea and vomiting in patients with advanced cancers over a time span of 24 months. Data collection used the medical records of patients who were institutionally approved to receive routine aroma applications for alleviating nausea and vomiting. The efficacy of using lemon oil pads was tested with one-dimensional chi-squared tests. Sixty-six patients received 222 applications of lemon oil on cotton pads; no data were available for 17 applications. The adequate relief of nausea and vomiting was reported for 149 (73%) applications, whereas no symptom control was seen for 56 (27%) applications. For the 56 applications without symptom control, first- and second-line rescue medications were successful in 53 and 3 cases, respectively. The use of aromatherapy with lemon oil pads against nausea and vomiting was feasible for 73% of all applications. All patients who did not benefit from aromatherapy had effective symptom control with a rescue medication. Large randomized prospective trials are necessary to evaluate the benefit of the use of lemon oil pads against nausea and vomiting in patients with advanced cancer.

Assessment of vegetation in Murchison falls national park five years after the completion of oil and gas exploration

Uganda discovered petroleum deposits in commercially viable quantities in 2006. Most areas such as Murchison Falls National Park (MFNP) where petroleum has been discovered overlap with wildlife and nature conservation with high biodiversity and sensitive ecosystems. This study sought to study the vegetation frequency index, relative abundance and diversity in former oil pads five years after the completion of oil and gas exploration in MFNP. We counted all observed plant species following a systematic random sampling technique using a (1mx1m) quadrat for herbs, (5mx5m) quadrat for shrubs, and (10mx10m) quadrat for trees. Data was collected using a 60m line transect to record the identified plant species. The study used a total of eight quadrats per transect and the total number of transects were 32. A quadrat was placed every after 7m along the line transect in and outside the oil pads. Each transect begun from the center (placard) of the oil pad going in directions of center to north, center to south, center to east, and center to west. This was carried out for purposes of replication and the same procedure was carried out for the control area. The same procedure was conducted at a frequency of wet (4th-30th April 2019) and dry (1st-30th June 2019) seasons. The counted data was later transformed and analyzed using t-statistical tests and chi- square tests in SPSS version 20 software. The study recorded uniform and non-uniform plant species and the mean vegetation diversity of 1.9±0.06 in oil pads and 1.71±0.12 in control areas. The study identified 31 different plant species, and among these, seven plant species were recorded in oil pads, eight in control areas. The results of vegetation relative abundance and diversity between oil pads and control areas were generally similar. However, the study observed some plant species such as Desert date (Balanites aegyptiaca) in control areas that were completely absent in oil pads. Further studies focusing on edaphic assessments, soil chemical, and biological analysis to better understand the impacts of oil exploration in the protected area are recommended.

IDENTIFYING OIL PADS IN HIGH SPATIAL RESOLUTION AERIAL IMAGES USING FASTER R-CNN

Abstract. Deep learning (DL) methods are used for identifying objects in aerial and ground-based images. Detecting vehicles, roads, buildings, and crops are examples of object identification applications using DL methods. Identifying complex natural and man-made features continues to be a challenge. Oil pads are an example of complex built features due to their shape, size, and presence of other structures like sheds. This work applies Faster Region-based Convolutional Neural Network (R-CNN), a DL-based object recognition method, for identifying oil pads in high spatial resolution (1m), true-color aerial images. Faster R-CNN is a region-based object identification method, consisting of Regional Proposal Network (RPN) that helps to find the area where the target can be possibly present in the images. If the target is present in the images, the Faster R-CNN algorithm will identify the area in an image as foreground and the rest as background. The algorithm was trained with oil pad locations that were manually annotated from orthorectified imagery acquired in 2017. Eighty percent of the annotated images were used for training and the number of epochs was increased from 100 to 1000 in increments of 100 with a fixed length of 1000. After determining the optimal number of epochs the performance of the algorithm was evaluated with an independent set of validation images consisting of frames with and without oil pads. Results indicate that the Faster R-CNN algorithm can be used for identifying oil pads in aerial images.

Terrestrial oil spill mapping using satellite earth observation and machine learning: A case study in South Sudan

Terrestrial oil spills are a major threat to environmental and human well-being. Rapid, accurate, and remote spatial assessment of oil contamination is critical to implementing countermeasures that prevent potentially lasting ecological damage and irreversible harm to local communities. Satellite remote sensing has been used to support such assessments in inaccessible regions, although mapping small terrestrial oil spills is challenging – partly due to the pixel size of remote sensing systems, but also due to the distinguishability of small oil spill areas from other land cover types. We assessed the usability of freely available Sentinel satellite images to map terrestrial oil spills with machine learning algorithms. Using two test sites in South Sudan, we demonstrated that information from the Sentinel-1 and -2 instruments can be used to map oil spills with more than 90 % classification accuracy. Classification accuracy was significantly increased (>95 %) with the addition of multi-temporal information and spatial predictor variables that quantify proximity to oil production infrastructure such as pipelines and oil pads. The mapping of terrestrial oil spills with freely available Sentinel satellite images may thus represent an accurate and efficient means for the regular monitoring of oil-impacted areas.

A passive compensated method with hydraulic transmission for static infinite stiffness of thrust bearing

Hydrostatic bearings are a core component of the worktable in heavy duty high-precision machine tools and a non-touch sliding pair composed of oil pads and guideway surfaces. The stiffness of an oil film produced by an oil pad is a key indicator that restricts the manufacturing precision and efficiency of machine tools. This paper presents a novel oil pad. It can withstand the impact of any step load in the designed range and always maintain the load position to only change in the submicron level. Therefore, the pad has the advantages of infinite stiffness and submicron precision stability. The pad performances were verified by the tests, and the theoretical, simulation and experimental results were highly consistent with one another.

Oil-water separation device based on super-hydrophobic material with multi-scale surface structure

A buoyancy-adaptive oil-water separation device is developed based on the prepared oil-water separation materials with a micro-nano hierarchical structure. This device can achieve the efficient recovery of diesel oil pads in the process of salt cavern construction without an external power source. The surface structure of superhydrophobic materials and the wettability of droplets on their surfaces are characterized. Then the separation mechanism is theoretically analysed. In addition, the brine breakthrough pressure and the separation efficiency of the device are studied considering the different surface structures of the separation materials. The mesh number and the layer number of separation materials are explored to determine their effects on the breakthrough pressure. It is found that this pressure increases with an increasing mesh number, but the influence of the screen layers is weak. Furthermore, the mesh number and the number of cycle separations that affect the separation efficiency are investigated. The results show that the sieve hole is smaller when the mesh number is larger, and the volume flow rate of diesel oil is thus reduced. Therefore, the screen mesh number should be reasonably selected based on the actual needs. The results of the cyclic separation test indicate that the separation material has good reusability. After 30 cycles of recycling, the separation efficiency of the device can still reach 90.1 ± 1.7%.

Effect of guide rail profile errors on the motion accuracy for a heavy-duty hydrostatic turntable

The motion accuracy of hydrostatic turntable is the key in improving the machining accuracy of heavy-duty machine tool. However, the motion accuracy of hydrostatic turntable depends not only on the offset load but also on the rotating speed of the turntable as well as the profile errors of the guide rails. In this paper, a simulation model is developed to analyze the effect of guide rail profile errors on the motion accuracy of hydrostatic turntable. The reaction forces of preload thrust bearing and hydrostatic circular oil pads are obtained based on the Reynolds equation of the lubricant film. The motion equations of hydrostatic turntable are derived in which the profile errors of two guide rails are considered. The results show that the motion accuracy of hydrostatic turntable can be affected by wavelength, amplitude of profile errors and speed, and offset load of turntable. Finally, the motion accuracy of heavy-duty hydrostatic turntable used in XCKA28105 type turning and milling composite machine tool is obtained by using the presented method. Comparing with the experimental results, the proposed model can be used to predict the machining accuracy caused by the profile errors of guide rails for any heavy-duty hydrostatic turntable.

Scale-dependent resource selection and space use by Mississippi Kite (Ictinia mississippiensis) in a heterogenous mixed-shrub ecosystem

Wildlife use and select habitat at multiple scales, sometimes leading to conflicting interpretations of the importance of various habitat features analyzed at different scales. Species can also exhibit affinities that are unique to portions within their larger distribution. Conservationists need spatially explicit information on habitat use to develop effective management strategies for priority species. This information can be difficult to obtain for species that are highly mobile or occupy large home ranges. In this study, we used a distance sampling approach to estimate multi-scale resource selection for a highly mobile raptor, Mississippi Kite (Ictinia mississippiensis), based on data collected from line transect surveys combined with plotting tools in a geographic information system. We compared land cover of kite detection points to randomly located points at fine and broad spatial scales in a portion of the species’ breeding range in the southern Great Plains, USA. Dominant cover in these landscapes is a mix of grasses, forbs, and expansive stands of a dwarf oak tree (Quercus havardii) generally < 1 m in height. Resource selection in Mississippi Kite was driven by both fine and broad-scale vegetation characteristics. At a fine scale (~ 13 ha), kites selected small, upland forest patches but avoided grass cover and riparian forest. At a broader scale (~ 200 ha), kites avoided oil pads but selected grass cover. Broad-scale selection also favored uplands farther away from riparian forest cover. Both observed density and predicted occurrence suggested riparian avoidance. Avoidance of riparian forest is atypical for Mississippi Kite, but might be explained in this system as avoidance of areas occupied by nest predators of kites, especially Great Horned Owl (Bubo virginianus).

Modeling and optimization of nonlinear support stiffness of hydrostatic ram under the impact of cutting force

PurposeThis paper aims to study the nonlinear supporting performance of hydrostatic ram under the impact of cutting force and search for an optimal solution to improve its stiffness.Design/methodology/approachThe Reynolds equation was applied to resolve the carrying capability of a single oil pad numerically, and an iteration method was used to analyze the nonlinear supporting force and stiffness of a pair of oil pads placed face-to-face. The total offset of ram could be obtained after the displacement of aspectant oil pads was solved by the bisection method. From the comparison of the offset values of ram evaluated under different support conditions, the optimal solution was determined.FindingsIn this study, an optimized oil supply allocation, concluded as 1.16:0.84, is proposed to improve the performance of hydrostatic ram supporting structure.Originality/valueThe supporting performance of hydrostatic ram could be improved by appropriate allocation of oil supply without extra energy consumption.

Optimization of Oil Pads on a Hydrostatic Turntable for Supporting Energy Conservation Based on Particle Swarm Optimization

Optimization of Oil Pads on a Hydrostatic Turntable for Supporting Energy Conservation Based on Particle Swarm Optimization

Are oil and natural gas development sites ecological traps for nesting killdeer?

Extraction of oil and natural gas is an emerging source of anthropogenic disturbance that threatens wild populations and important wildlife habitats. We compared daily nest survival estimates of killdeer Charadrius vociferous at graveled oil pads to those that nested on native grass cover in western Oklahoma, USA in 2015 and 2017. We conducted weekly searches for nesting killdeer around oil pads and in pastures (grass cover) at the Packsaddle Wildlife Management Area April–June. Killdeer showed a strong selection for graveled oil pad over grass fields with 64% of all nest attempts occurring on oil pads. A higher proportion (64%) of the nests we found were in the gravel substrates of oil pads, and daily nest survival estimates for oil pad nests were lower than our estimates for nests in grass substrates. We also identified a difference in edge effects between the two nesting substrates with the probability of nest survival on oil pads highest closer to the edge of the patches and the probability of nest survival in grass cover highest in the interior of the patches. This is an indication that risk of nest failure on oil pads increased towards areas of high human use: Nest failure on oil pads was almost entirely due to destruction by moving vehicles and by oil workers performing routine operations at well sites. Our results demonstrate that modified landscapes attract native species but could function as ecological traps. Management efforts to reduce the effect of oil and natural gas development or similar forms of human land use modifications on co‐occurring nesting birds will benefit from reduction in habitat conversion and incorporation of natural gas developments into conservation planning.

Simulation and experimental analysis of supporting characteristics of multiple oil pad hydrostatic bearing disk

To study the heavy hydrostatic bearing with multiple oil pads, a reasonably simplified model of the pad is put forward, and the mathematical model of the bearing characteristics of the multiple oil pad hydrostatic bearing is built with consideration of variable viscosity. The pressure field in the clearance oil film of the hydrostatic bearing at various velocities is simulated based on the Finite Volume Method (FVM) by using the software of Computational Fluid Dynamics (CFD). Some pressure experiments on the hydrostatic bearing were carried out and the results verified the rationality of the simplified model of the pad and the validity of the numerical simulation. It is concluded that the viscosity has a great influence on the pressure in the heavy hydrostatic bearing and cannot be neglected, especially, in cases of high rotating speed. The results of numerical calculations provide the internal flow states inside the bearing, which would help the design of the oil cavity structure of the bearing in engineering practice.

Supporting Force Analysis of Oil Pads in Hydrostatic Rotary Table of Heavy Duty CNC Machine

According to the characteristics of constant flow and closed hydrostatic rotary table used in heavy duty CNC machine, in order to consider the interaction between structural deformation of worktable and the supporting force of oil pads, an iteration method between hydrostatic theory calculation and finite element method (FEM) is used to get the real supporting force of each oil pad at different carrying state. The result is compared with the situation which is not considering the deformation of worktable and the difference between them can be used to guide the design of hydrostatic oil pads. The optimal radius of supporting point of work piece is also achieved using this method, which can provide theory basis for supporting point distribution of heavy work piece.

Numerical Calculation and Analysis of Dynamic Pressure Effect for Heavy Hydrostatic Bearing Disk with Multiple Oil Pads

Numerical Calculation and Analysis of Dynamic Pressure Effect for Heavy Hydrostatic Bearing Disk with Multiple Oil Pads

Analysis on Influence of Oil Film Thickness on Temperature Field of Heavy Hydrostatic Bearing in Variable Viscosity Condition

According to the problem of the influence of oil film thickness on temperature rise for heavy hydrostatic thrust bearing during operation， build viscosity-temperature equation of lubricating oil film and mathematics model of oil film temperature rise of heavy hydrostatic bearing with multiple oil pads, simulate the temperature field of hydrostatic bearing with sector cavity under various oil film thickness using FVM(finite volume method), and reveal the influence law of oil film thickness of temperature rise for hydrostatic bearing. The results show that temperature distribution of hydrostatic bearing is much the same under various oil film thicknesses, but the influence of oil film thickness of temperature rise for hydrostatic bearing is greater. The results of numerical calculations actually response flow state inside hydrostatic bearing ，offer theoretical foundation for the design of hydrostatic bearing in engineering practice, and have important significance in improving operation stability of NC machine.

LARGE REFLECTOR FOR THE LICK OBSERVATORY

Following the appropriation of funds by the State Legislature in February 1946, detailed engineering design of a large reflector for the Lick Observatory was started immediately. By November 1946, the basic features of the telescope were sufficiently well established to permit the construction of a 1/16-scale model, which is shown without its enclosing dome in Plate XXIV. The proposed aperture is 120 inches, the focal ratio F/5. The mounting will be a long fork of welded-steel construction. The fork will turn in oil-pad bearings, with the north and south bearings spaced 20 feet apart. The thrust will be taken by oil pads located at the south end of the polar axis. In the model, rollers are substituted for the oil pads. The tube design is similar to that developed by Mark Serrurier for the 200-inch telescope, except that the declination axis will be located a quarter of the length of the tube up from the mirror, instead of near the center of the tube. The polar axis is to be mounted on a welded-steel structure supported by three leveling and aligning jacks. A vertical line through the center of gravity of the entire instrument will fall well within the area of the base.