Journal articles: 'PDC bit performance'

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JPT staff, _. "Steel-Body PDC-Bit Technology Improves Bit Performance." Journal of Petroleum Technology 50, no. 12 (December 1, 1998): 42–43. http://dx.doi.org/10.2118/1298-0042-jpt.

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JPT staff, _. "PDC-Bit Performance in Deep Shales." Journal of Petroleum Technology 50, no. 12 (December 1, 1998): 44–46. http://dx.doi.org/10.2118/1298-0044-jpt.

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Andersen, E. E., and J. J. Azar. "PDC Bit Performance Under Simulated Borehole Conditions." SPE Drilling & Completion 8, no. 03 (September 1, 1993): 184–88. http://dx.doi.org/10.2118/20412-pa.

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Ayop, Ahmad Zhafran, Ahmad Zafri Bahruddin, Belladonna Maulianda, Aruvin Prakasan, Shamammet Dovletov, Eziz Atdayev, Ahmad Majdi Abdul Rani, et al. "Numerical modeling on drilling fluid and cutter design effect on drilling bit cutter thermal wear and breakdown." Journal of Petroleum Exploration and Production Technology 10, no. 3 (October 11, 2019): 959–68. http://dx.doi.org/10.1007/s13202-019-00790-7.

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Abstract The unconventional reservoir geological complexity will reduce the drilling bit performance. The drill bit poor performance was the reduction in rate of penetration (ROP) due to bit balling and worn cutter and downhole vibrations that led to polycrystalline diamond compact (PDC) cutter to break prematurely. These poor performances were caused by drilling the transitional formations (interbedded formations) that could create huge imbalance of forces, causing downhole vibration which led to PDC cutter breakage and thermal wear. These consequently caused worn cutter which lowered the ROP. This low performance required necessary improvements in drill bit cutter design. This research investigates thermal–mechanical wear of three specific PDC cutters: standard chamfered, ax, and stinger on the application of heat flux and cooling effect by different drilling fluids by using FEM. Based on simulation results, the best combination to be used was chamfered cutter geometry with OBM or stinger cutter geometry with SBM. Modeling studies require experimental validation of the results.

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Li, Yan, Yin Fang Song, and Yi Lin Mao. "Study on the Statics Analysis of Promoting the Drilling Efficiency of PDC Anchor Bit." Advanced Materials Research 989-994 (July 2014): 2749–52. http://dx.doi.org/10.4028/www.scientific.net/amr.989-994.2749.

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PDC anchor bit has the very good rock fragmentation abilities with high penetration rate and long drilling time,which makes the drilling efficiency highly improved and the economic benefit remarkably increased.Now PDC anchor bit has been widely used in drilling field.But for the reason that it is sensitive to the formation characteristics and working conditions,it doesn’t achieve good performance in homogeneous formations such as conglomerate and interbeded sections.In order to reach the goal of enlarging the scope of PDC anchor bit application in oilfields,it is necessary to study the breakage mechanism in conglomerate formations and design the PDC anchor bit optimally.

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Karasawa, H., and S. Misawa. "Development of New PDC Bits for Drilling of Geothermal Wells—Part 1: Laboratory Testing." Journal of Energy Resources Technology 114, no. 4 (December 1, 1992): 323–31. http://dx.doi.org/10.1115/1.2905960.

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Rock cutting, drilling and durability tests were conducted in order to obtain data to design polycrystalline diamond compact (PDC) bits for geothermal well drilling. Both conventional and new PDC bits with different rake angles were tested. The rock cutting tests revealed that cutting forces were minimized at −10 deg rake angle independent of rock type. In drilling and durability tests, a bit with backrake and siderake angles of −10 or −15 deg showed better performance concerning the penetration rate and the cutter strength. The new PDC bit exhibited better performance as compared to the conventional one, especially in hard rock drilling. Furthermore, a new PDC core bit (98.4 mm o. d., 66 mm i. d.) with eight cutters could be successfully applied to granite drilling equally as well as a bit with twelve cutters.

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Clement, Alaba O. "Comparative analysis of drilling performance of kymera and PDC bits in salt formation." Brilliant Engineering 1, no. 2 (January 5, 2020): 25–28. http://dx.doi.org/10.36937/ben.2020.002.005.

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The study compares the drilling performance of Kymera and PDC bits in salt formation using River and Delta State Continental Shelf of Nigeria as a case study. The measurement while drilling (MWD) and the logging while drilling (LWD) methods were used to measure the real time well drilling operation. well formation and drilling statistics. The data obtained from the Ogbaimbiri. Ossiomo. Utorogu and Okporhuftu wells have the penetration rate of 6.2 m/hr. 5.9 m/hr. 12.2 m/hr. 6.3 m/hr for Kymera bit and 4.2 m/hr. 3.4 m/hr. 6.8 m/hr. 3.9 m/hr for PDC bit respectively. The pearson correlation coefficient has a value of r = 0.897. n = 4. p<0.05 and r = 0.784. n = 4. p<0.05 for both kymera and PDC bits. The results established a strong and positive correlation between the penetration rate and distance drilled in each bit. It also shows that the higher the penetration rate the more the distance drilled by each bit. The study concluded that the Kymera bit was more efficient as it was able to penetrate the different formations with a lesser time and at a greater penetration rate.

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Wojtanowicz, A. K., and E. Kuru. "Mathematical Modeling of PDC Bit Drilling Process Based on a Single-Cutter Mechanics." Journal of Energy Resources Technology 115, no. 4 (December 1, 1993): 247–56. http://dx.doi.org/10.1115/1.2906429.

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An analytical development of a new mechanistic drilling model for polycrystalline diamond compact (PDC) bits is presented. The derivation accounts for static balance of forces acting on a single PDC cutter and is based on assumed similarity between bit and cutter. The model is fully explicit with physical meanings given to all constants and functions. Three equations constitute the mathematical model: torque, drilling rate, and bit life. The equations comprise cutter’s geometry, rock properties drilling parameters, and four empirical constants. The constants are used to match the model to a PDC drilling process. Also presented are qualitative and predictive verifications of the model. Qualitative verification shows that the model’s response to drilling process variables is similar to the behavior of full-size PDC bits. However, accuracy of the model’s predictions of PDC bit performance is limited primarily by imprecision of bit-dull evaluation. The verification study is based upon the reported laboratory drilling and field drilling tests as well as field data collected by the authors.

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JPT staff, _. "Cooperative Approach Yields Better Understanding of PDC-Bit Performance." Journal of Petroleum Technology 50, no. 12 (December 1, 1998): 34–36. http://dx.doi.org/10.2118/1298-0034-jpt.

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Huang, Kuilin, Chunxiao Zhou, Yingxin Yang, Haitao Ren, and Qingzhi Niu. "Working Load Characteristics of the PDC-Cone Composite Bit under Impact and Scraping." Shock and Vibration 2020 (January 31, 2020): 1–9. http://dx.doi.org/10.1155/2020/7540519.

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The PDC-roller hybrid bit combines the cutting structure of a tricone bit with a PDC bit. It can achieve good results, breaking rock in directional drilling, drilling in inhomogeneous formations, and drilling in formations with high levels of hardness, and it can achieve the engineering goals of increasing speed and efficiency. First, we analyzed the rock-breaking mechanism of the composite bit and the principles of cushioning, torsion reduction, and prebreaking of the cone teeth during the breaking of rock. Second, cutting load models of the cone teeth and PDC teeth were established through unit experiments and through the calculation methods of the axial force, lateral force and torque, and lateral bending moment of the composite bit. Third, the digital simulation and analysis system was improved to include the function of calculating the working load of the composite bit. Taking an 8-1/2 inch, 2 + 4 type composite bit as an example, the working load characteristics of three cutting structures (cone, blade, and composite) were analyzed and compared. The analysis shows that the composite bit has high drilling efficiency, obvious deviation advantages, and good working stability under specific formation conditions. This paper provides technical support for the performance analysis, formation adaptability evaluation, and cutting structure design optimization of the PDC-cone bit.

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Garcia-Gavito, D., and J. J. Azar. "Proper Nozzle Location, Bit Profile, and Cutter Arrangement Affect PDC-Bit Performance Significantly." SPE Drilling & Completion 9, no. 03 (September 1, 1994): 167–75. http://dx.doi.org/10.2118/20415-pa.

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Khuzina, L. B., and A. F. Shaikhutdinova. "TECHNOLOGY SOLUTION FOR IMPROVEMENTOF THE PDC DRILL BITS PERFORMANCE." Oil and Gas Studies, no. 4 (September 1, 2016): 84–87. http://dx.doi.org/10.31660/0445-0108-2016-4-84-87.

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The article is devoted to the problem of bringing the desired load to the drill bit and improving the technical and economic indexes of drilling at drilling the oil and gas wells. The authors propose a bottom-hole assembly (BHA) consisting of PDC bits, downhole oscillator, screw downhole motor, measuring-while drilling system and drill pipes. The results of the proposed assembly pilot tests are presented. The tests were conducted in well No. 6053 in Sheremetyev field, Tatarstan Republic.

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Black, A. D., B. H. Walker, G. A. Tibbitts, and J. L. Sandstrom. "PDC Bit Performance for Rotary, Mud Motor, and Turbine Drilling Applications." SPE Drilling Engineering 1, no. 06 (December 1, 1986): 409–16. http://dx.doi.org/10.2118/13258-pa.

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Kuru, E., and A. K. Wojtanowicz. "A Compound Effect of Cutting Depth and Bit Dull on Cutters’ Temperature for Polycrystalline Diamond Compact Bits." Journal of Energy Resources Technology 115, no. 2 (June 1, 1993): 124–32. http://dx.doi.org/10.1115/1.2905979.

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This paper presents a simulation study to evaluate the combined effect of cutting depth (drilling rate) and wear (bit dull) on the thermal response of polycrystalline diamond compact (PDC) cutters under downhole drilling conditions. A new understanding of frictionally generated heat between rock and PDC cutter is introduced from the analysis of forces active on the wearflat and the cutting (leading) surfaces of a cutter. Then this new concept is used to predict PDC bit performance with the controlled temperature of its cutters. Previous concepts, largely based on the laboratory drilling tests (with low drilling rate and under atmospheric conditions), recognize only one source of heat—the wearflat surface. However, this study, using field data, shows that the heat generated at the cutting surface may significantly contribute to the total heat flux in the cutter. As a result, the distribution of temperature within the cutter is changed, which particularly affects the maximum value of temperature at the cutting edge. A simplified 2-D finite difference numerical code is used to quantify the difference in cutter wearflat temperatures calculated with and without the additional heat flux generated at the cutting surface. The numerical analysis reveals that neglecting the cutting surface effect results in underestimation of the actual wearflat temperature by 10 to 530 percent, depending upon bit dull and downhole hydraulics. Also demonstrated is the actual impact of these findings on field drilling practices. The example comparison is made by calculating the optimal-control procedures for PDC bit with and without the effect of cutting surface. In these procedures, wearflat temperature becomes a mathematical constraint which limits weight on bit and rotational speed. The comparison includes calculation of the maximum bit performance curves which represent maximum drilling rate attainable for a bit to drill a predetermined length of a borehole (footage). The curves show an up to 18 percent reduction of drilling rate when the new and more rigorous temperature limitation is used. In addition, the example calculations show that the actual temperature of the bit cutters can be 460°C (860°F), and exceeds by almost 30 percent its maximum acceptable value of 350°C (660°F). For practical applications, the study reveals that many field failures of PDC bits may have been caused by lack of understanding of operational limits imposed by heat considerations.

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Wei, Zhong Liang, Hai Peng Lin, Juan Juan Du, and Yue Yong Pan. "The Design Technology of PDC Bit in The High Hardness and Abrasiveness Formation of Xishanyao." Advanced Materials Research 201-203 (February 2011): 1535–38. http://dx.doi.org/10.4028/www.scientific.net/amr.201-203.1535.

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High hardness and abrasiveness, low ROP and seriously deviation are the features of Shanle block Xishanyao formation in Turpan-Hami Oilfield, whose lithology was conglomerate, glutenite, interbedded sandstone, large angle of bedding and many fractures. To enhance ROP at this high hardness and abrasive region, designing of PDC bit is introduced based on crown shape, blade, teeth, bit hydraulics and so on. The designed bit had a good performance in the test of Well He-3 at Shanle block.

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Won, Keith, Ming Zo Tan, and I. Made Budi Utamain. "Double-section, non-retrievable casing drilling technique." APPEA Journal 52, no. 1 (2012): 261. http://dx.doi.org/10.1071/aj11019.

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With the continuous surging in daily rental rates of oilfield exploration rigs, Casing while Drilling technology—which provides operators with an alternative drilling solution for a reduction in drilling flat-time and increased drilling operation efficiency—has appeared to be a standard part of drilling engineers’ toolkit in the well-planning process. Significant cost savings generated by Casing while Drilling have contributed to this technique being widely deployed on top-hole string installations on exploration and appraisal wells in the southeast Asia region. The double-section casing drilling technique has gained increasing popularity among operators in recent years; however, this technique development has been hamstrung by limited casing bit selections. An improved design casing bit has been highly anticipated in the industry to reduce this technique’s complexity of drilling process. Finding an equilibrium between durability and drill-out capability features for a casing bit has been a major challenge for bit designers. The increasing prospect and demand for a double-section casing drilling technique, however, has yielded the development of the casing bit design to a wider portfolio, inclusive of a more robust PDC (polycrystalline diamond compact) cutter-based drillable casing bit. The introduction of the new robust but drillable PDC cutter-based casing bit has broadened the Casing while Drilling application. The double-section casing drilling technique without the need for an additional conventional clean-out trip has become a strong contender to be part of drilling engineers’ next toolkit in delivering enhanced drilling performance and increasing operational efficiencies. This paper will introduce the first case history of the successful planning and implementation of the double-section casing drilling technique—particularly emphasising its optimised drilling performance and ease of drill-out without the need for a specialised drill-out bit.

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Bazaluk, Oleg, Andrii Velychkovych, Liubomyr Ropyak, Mykhailo Pashechko, Tetiana Pryhorovska, and Vasyl Lozynskyi. "Influence of Heavy Weight Drill Pipe Material and Drill Bit Manufacturing Errors on Stress State of Steel Blades." Energies 14, no. 14 (July 12, 2021): 4198. http://dx.doi.org/10.3390/en14144198.

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Drilling volumes should be increased in order to increase hydrocarbon production, but this is impossible without the usage of high-quality drilling tools made of modern structural materials. The study has to analyze the design, technological and operational methods to increase the performance of drilling tools made of various materials and has highlighted prospects of technological method applications. The scientific novelty of the study consists in the development of a new analytical model of PDC drill bit–well interaction. The developed model takes into account the drill bit manufacturing errors in the form of bit body–nipple axes misalignment on the drill bit strength. This result makes it possible to determine the permissible manufacturing errors to provide safe operation of the drill bit. It is established that there is an additional transverse force that presses the drill bit to the well wall in the rock due to manufacturing errors. It is determined that the magnitude of this clamping force can be significant. The material effect has been analyzed on additional clamping force. It is established that geometric imperfection of the drill bit causes the minimal effect for the elastic system of the pipe string, which includes a calibrator and is composed of drill pipes based on composite carbon fiber material, and the maximal effect—for steel drill pipes. Polycrystalline diamond compact (PDC) drill bit and well wall contact interaction during operation in non-standard mode is considered. Non-standard stresses are determined, and the strength of the blades is estimated for different values of drilling bit manufacturing error.

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Gupta, Sumit, and Aditya Goel. "Design of Multiservice Code (MS) in Spectral/Temporal/Spatial Domain for OCDMA System." Journal of Optical Communications 41, no. 3 (April 28, 2020): 305–17. http://dx.doi.org/10.1515/joc-2017-0180.

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AbstractThis paper explores the design of multiservice code (MS) in spectral, time spreading and wavelength domains (3-Dimensional). The proposed 3D code is designed in such a manner that follows the ideal in phase unit cross correlation in spectral, time spreading and wavelength domains. The proposed encoder generates the MS code effectively in 3D domain and decoder suppresses the multi-user interferences successfully. Performance analyses are carried out by considering the all noises such as phase induce intensity noise(PIIN), shot noise and thermal noise. The analysis of 3D-MS code for variable code length is also performed for measurement of variation in bit error rate against the received power and number of active users in the design. The observed performances are also compared with existing codes such as 2D-MDW, 3D-PDC and 1D-MS code and the proposed code shows the better performance. The analysis of bit error rate of proposed code is carried out against the number of users at 0.622Gbits/s data rate and 0 dBm received power and comparison is also formed with the existing code such as 3D PD(M=21, N=3, P=3), 2DMDW(M=63, P=3), PDC(M=57, P=3) and 1D MS Code. It is noted that 3D MS code shows the better performance than the existing methods. Analysis is also evaluated for variable weight and variable length codes in order to observe the variation in bit error rate with variation in received power and number of simultaneous users.

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Mazen, Ahmed Z., Iqbal M. Mujtaba, Ali Hassanpour, and Nejat Rahmanian. "Mathematical modelling of performance and wear prediction of PDC drill bits: Impact of bit profile, bit hydraulic, and rock strength." Journal of Petroleum Science and Engineering 188 (May 2020): 106849. http://dx.doi.org/10.1016/j.petrol.2019.106849.

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Naser, Manar Ahmed. "An Optimum Bits Selection for a Southern Iraqi Oil Field Located in Basra Region by Depending a New Algorithm." Journal of Petroleum Research and Studies 4, no. 3 (December 1, 2013): 16–44. http://dx.doi.org/10.52716/jprs.v4i3.116.

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Even drill bits cost are about 3-5% of the total drilling budget, but bits performance affects as much as 60% of the drilling cost[1] that would explain the necessity of continuous studying and developing this tool to improve drilling performance. Unfortunately, most of Iraqi oil fields managed by states companies does not give the proper attention for bits optimization issues, that would cause insufficient bits used to drill a certain formation due to the absence of a serious dealing with formation hardness and other bit selection criteria while designing, or making bits purchases contracts, or they would satisfy by a minimum rates of penetration. Unfortunately, the bit selection issue is matched the optimum selection for the drilling parameters issue, it is a matter of tri and error [2]. In this study, a southern Iraqi oil field located in Basra region have been selected to optimize the bits used to drill its wells. Summarizations of bits selection methods have been reviewed, advantages and disadvantages of possibility to applicant those methods in Basra regions have been introduced. A proper algorithm for selecting bits in Iraq was also presented. An economic evaluation for a different bit type's strategies used to drill holes of Mishrif wells in Basra oil fields region also discussed. This study improve that using bits holding the IADC code 425, M322 PDC bit with 6th blades and 16mm cutter size and M323 PDC bit with 5th blades and 6mm cutter size are the optimum selection to drill the surface, intermediate, and production holes consequently. This study is applicable to all Iraqi oil fields and especially for Basra region oil fields due to its large analogous on the lithology column and the drilling problems may combined the drilling operations among the different oil fields in this area.

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Mazen, Ahmed Z., Nejat Rahmanian, Iqbal M. Mujtaba, and Ali Hassanpour. "Effective mechanical specific energy: A new approach for evaluating PDC bit performance and cutters wear." Journal of Petroleum Science and Engineering 196 (January 2021): 108030. http://dx.doi.org/10.1016/j.petrol.2020.108030.

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Wojtanowicz, A. K., and E. Kuru. "Minimum-Cost Well Drilling Strategy Using Dynamic Programming." Journal of Energy Resources Technology 115, no. 4 (December 1, 1993): 239–46. http://dx.doi.org/10.1115/1.2906428.

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This paper presents an advanced concept in drilling optimization—the dynamic drilling strategy. The dynamic drilling strategy is a new methodology of drilling process planning and control; it combines theory of single-bit control with an optimal multi-bit drilling program for a well. In the simulation study, the dynamic drilling strategy was compared to conventional drilling optimization and typical field practices; the considerable cost-saving potential of 25 and 60 percent, respectively, was estimated. The method also appeared to be the most cost-effective for expensive and long-lasting PDC bits through better utilization of their performance and reduction in the number of bits needed for the hole.

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Zhang, Li Gang, Tie Yan, and Shi Bin Li. "Design of High-Efficient Bits for Igneous Rock in Xushen Gasfield." Applied Mechanics and Materials 385-386 (August 2013): 308–11. http://dx.doi.org/10.4028/www.scientific.net/amm.385-386.308.

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The igneous rocks in deep formations of the Xushen gasfield have the following characters: high abrasive property, high hardness, and high drillability, which lead to many drill bit accidents, few footage per bit , low efficiency of drilling, long drilling cycle, these severely restrict the exploration and development process of gas field. According to the features of deep formation, a hybird cutters bit is designed. It has three cones, with the overhang cone , duplicate taper and offset cone characters. The tungsten carbide cutters and the polycrystalline diamond compacts cutters are alternative collocation in the same tooth row in the bit. The exposed height of the tungsten carbide cutters is higher than polycrystalline diamond compacts cutters. The back rake angle of polycrystalline diamond compacts cutters is 10 ~ 40 °, the side rake angle is 10 ~ 30 °. The normal direction of working face stay the same with the composite slip direction, and the side rake pointed at adjacent gullet. Through the design method, it is integrated that the advantages of roller bit and PDC bit, the way of impact breakage and rotational shear breakage and the prominent performance of tungsten carbide cutters and polycrystalline diamond compacts cutters. It can improveROP and bit life.

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Clydesdale, G. M., A. Leseultre, and E. Lamine. "Low Invasion Corehead Reduces Mud Invasion While Improving Performances." Journal of Energy Resources Technology 116, no. 4 (December 1, 1994): 258–67. http://dx.doi.org/10.1115/1.2906451.

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A corehead was designed, manufactured and tested to reduce fluid invasion of the core. This is obtained by minimizing the exposure time of the core to the drilling fluid in increasing the rate of penetration (ROP). The design incorporates a medium heavyset polycrystalline diamond compact (PDC) cutting structure developed in accordance with cutting models and balancing methods used for drill bits. The highest ROP is achieved by a particular hydraulic design: flow ports shape and positioning to clean the cutting structure enhance the drilled cuttings removal while preventing drilling fluid in the throat of the corehead. Moreover, an internal lip works with a special inner barrel shoe to effectively seal off mud flow from the throat. All the design features have been subjected to laboratory tests, including measurement of pressure drop across the corehead and flow visualization studies. Flow visualization tests include high-speed filming of the flow and paint tracing to indicate the special flow pattern. In conjunction with lab tests, a numerical simulation was performed using fluid dynamics software to optimize hydraulic parameters. The low invasion core bit has been used in numerous applications. The performance achieved was significantly better than the average achieved over a period of years using various PDC coreheads. The rate of penetration was increased by a factor of 4.8 and bit life by 2.3 (often with reusable condition).

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Chen, Shilin, Rob Arfele, Seth Anderle, and Jorge Romero. "A New Theory on Cutter Layout for Improving PDC-Bit Performance in Hard-and Transit-Formation Drilling." SPE Drilling & Completion 28, no. 04 (December 1, 2013): 338–49. http://dx.doi.org/10.2118/168224-pa.

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Carpenter, Chris. "Data Analytics and Physics-Based Simulation Enable Bit, Motor, and BHA Combination." Journal of Petroleum Technology 72, no. 12 (December 1, 2020): 53–54. http://dx.doi.org/10.2118/1220-0053-jpt.

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This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper OTC 29875, “Combined Data Analytics and Physics-Based Simulation for Optimal Bit, Motor, and Bottomhole Assembly Combination,” by Samba Ba, SPE, Dmitry Belov, SPE, and Daniel Nobre, SPE, Schlumberger, et al., prepared for the 2019 Offshore Technology Conference Brasil, Rio de Janeiro, 29-31 October. The paper has not been peer reviewed. Copyright 2020 Offshore Technology Conference. Reproduced by permission. Today, drill bits and mud motor issues can account for more than half of the reasons for pulling out of hole before total depth (TD) on directional drilling wells. The complete paper presents a methodology designed for optimally matching drill bits, mud motors, and bottomhole-assembly (BHA) components for reduced failure risks and improved drilling performance. Work Flow The overall work flow includes detailed modeling of each sophisticated component and an algorithm to combine them efficiently at the system level without losing their specific nature. Drilling-Bit Simulation. The drill-bit model is created in 4D - 3D space modeling plus the transient behavior with time. In 4D finite-element modeling, both polycrystalline-diamond-compact (PDC) and reverse-circulation bits can be modeled. The detailed cutting structure model may include specifying the number of cutters and how to place them in a 3D cutter space. The bit cutter and rock interaction must be modeled correctly to simulate the real scenario. This interaction is characterized by laboratory testing for almost all types of rocks interacting with the cutters. Motor Simulation. The mud motor consists of multiple subassemblies. The power section assembly is where the transformation of hydraulic power into mechanical power occurs; this consists of a rotor/stator pair. The rotor is the moving part and the stationary stator is a metal tube with rubber bonded inside. The authors developed a motor- optimization modeling work flow for evaluating the mud motor’s performance and durability for any defined drilling conditions. This model includes performance, fatigue, and hysteresis heating simulation capabilities. Within the framework of the developed work flow, the authors use three types of simulation (mechanical, thermal, and fatigue), with mutual correlations between the results. Drillstring Simulation. A proper drill-string simulation is critical for the successful evaluation of drilling performance and equipment reliability. In this study, the drillstring and BHA analysis consists of a comprehensive full-scale finite-element model that also includes a proper transient analysis of the drilling process in a 4D analysis. This finite- element model uses 3D beam elements with six degrees of freedom for each finite-element node. The described complex finite-element model incorporates all components from drill bit to surface. This model considers factors affecting the dynamic performance of the drillstring and can predict the transient response in the time domain. Detailed working mechanisms and geometries of downhole drive tools were implemented in the model to study the dynamic characteristics and directional performance of these tools.

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Sugiura, Junichi, and Steve Jones. "Measurement of Mud Motor Back-Drive Dynamics, Associated Risks, and Benefits of Real-Time Detection and Mitigation Measures." SPE Drilling & Completion 36, no. 03 (February 25, 2021): 628–46. http://dx.doi.org/10.2118/204032-pa.

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Summary North American shale drilling is a fast-paced environment where downhole drilling equipment is pushed to the limits for the maximum rate of penetration (ROP). Downhole mud motor power sections have rapidly advanced to deliver more horsepower and torque, resulting in different downhole dynamics that have not been identified in the past. High-frequency (HF) compact drilling dynamics recorders embedded in the drill bit, mud motor bit box, and motor top subassembly (top-sub) provide unique measurements to fully understand the reaction of the steerable-motor power section under load relative to the type of rock being drilled. Three-axis shock, gyro, and temperature sensors placed above and below the power section measure the dynamic response of power transfer to the bit and associated losses caused by back-drive dynamics. Detection of back-drive from surface measurements is not possible, and many measurement-while-drilling (MWD) systems do not have the measurement capability to identify the problem. Motor back-drive dynamics severity is dependent on many factors, including formation type, bit type, power section, weight on bit, and drillpipe size. The torsional energy stored and released in the drillstring can be high because of the interaction between surface rotation speed/torque output and mud motor downhole rotation speed/torque. Torsional drillstring energy wind-up and release results in variable power output at the bit, inconsistent rate of penetration, rapid fatigue on downhole equipment, and motor or drillstring backoffs and twistoffs. A new mechanism of motor back-drive dynamics caused by the use of an MWD pulser above a steerable motor has been discovered. HF continuous gyro sensors and pressure sensors were deployed to capture the mechanism in which a positive mud pulser reduces as much as one-third of the mud flow in the motor and bit rotation speed, creating a propensity for a bit to come to a complete stop in certain conditions and for the motor to rotate the drillstring backward. We have observed the backward rotation of a polycrystalline diamond compact (PDC) drill bit during severe stick-slip and back-drive events (−50 rev/min above the motor), confirming that the bit rotated backward for 9 milliseconds (ms) every 133.3 ms (at 7.5 Hz), using a 1,000-Hz continuous sampling/recording in-bit gyro. In one field test, multiple drillstring dynamics recorders were used to measure the motor back-drive severity along the drillstring. It was discovered that the back-drive dynamics are worse at the drillstring, approximately 1,110 ft behind the bit, than these measured at the motor top-sub position. These dynamics caused drillstring backoffs and twistoffs in a particular field. A motor back-drive mitigation tool was used in the field to compare the runs with and without the mitigation tool while keeping the surface drilling parameters nearly the same. The downhole drilling dynamics sensors were used to confirm that the mitigation tool significantly reduced stick-slip and eliminated the motor back-drive dynamics in the same depth interval. Detailed analysis of the HF embedded downhole sensor data provides an in-depth understanding of mud motor back-drive dynamics. The cause, severity, reduction in drilling performance and risk of incident can be identified, allowing performance and cost gains to be realized. This paper will detail the advantages to understanding and reducing motor back-drive dynamics, a topic that has not commonly been discussed in the past.

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Wang, Wei, Jun Li, Gong Hui Liu, and Chun Qing Cha. "Research on Design of Polycrystalline Diamond Composite Pendulum Wear-Resistant Belt." Materials Science Forum 944 (January 2019): 999–1004. http://dx.doi.org/10.4028/www.scientific.net/msf.944.999.

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The torque impactor can effectively solve the stick-slip vibration of PDC bit in the deep formation, but the wear of the pendulum seriously restricted the service life of the impactor. In order to reduce the wear of the pendulum under complicated working conditions, the polycrystalline diamond composite material was used as the wear-resistant material to design the pendulum wear-resistant belt. Based on the analysis of the feasibility of using polycrystalline diamond as pendulum wear-resistant material, the finite element model of dynamic contact interaction between pendulum wear-resistant belt and impact cylinder was established, the influence of the arrangement of wear-resistant blocks on the stress of the contact area between the pendulum wear-resistant belt and the impact cylinder was studied. The results show: Polycrystalline diamond composite material has stronger wear resistance and better anti-friction performance than conventional wear-resistant materials, and can reduce the wear of the inner wall of the impact cylinder, which is feasible on the surface of the pendulum hammer. The use of the wear-resistant belt structure is beneficial to improve the variation of the shear stress of the area where the pendulum and the impact cylinder contact each other. The wear-resistant belt structure is beneficial to improve the shear stress variation amplitude of the pendulum and impact cylinder in contact with each other. When the wear-resistant block is arranged in a circular block staggered arrangement, the shear stress change amplitude of the interaction contact area is the largest, the triangular block staggered arrangement mode is second, and the trough block shape staggered arrangement is the smallest. The research results have important reference significance for the design and application of polycrystalline diamond composite pendulum wear-resistant belt.

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Ogawa, Koichi, and Jun‐ichi Takada. "An analysis of the effective performance of a handset diversity antenna influenced by head, hand, and shoulder effects—A proposal for a diversity antenna gain based on a signal bit‐error rate and analytical results for the PDC system." Electronics and Communications in Japan (Part II: Electronics) 84, no. 6 (June 2001): 10–23. http://dx.doi.org/10.1002/ecjb.1031.

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Arıkan, Erdal. "Systematic Encoding and Shortening of PAC Codes." Entropy 22, no. 11 (November 15, 2020): 1301. http://dx.doi.org/10.3390/e22111301.

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Polarization adjusted convolutional (PAC) codes are a class of codes that combine channel polarization with convolutional coding. PAC codes are of interest for their high performance. This paper presents a systematic encoding and shortening method for PAC codes. Systematic encoding is important for lowering the bit-error rate (BER) of PAC codes. Shortening is important for adjusting the block length of PAC codes. It is shown that systematic encoding and shortening of PAC codes can be carried out in a unified framework.

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Zhang, Shengqi, Yateendra Mishra, Bei Yuan, Jianfeng Zhao, and Mohammad Shahidehpour. "Primary Frequency Controller with Prediction-Based Droop Coefficient for Wind-Storage Systems under Spot Market Rules." Energies 11, no. 9 (September 5, 2018): 2340. http://dx.doi.org/10.3390/en11092340.

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Increasing penetration levels of asynchronous wind turbine generators (WTG) reduce the ability of the power system to maintain adequate frequency responses. WTG with the installation of battery energy storage systems (BESS) as wind-storage systems (WSS), not only reduce the intermittency but also provide a frequency response. Meanwhile, many studies indicate that using the dynamic droop coefficient of WSS in primary frequency control (PFC) based on the prediction values, is an effective way to enable the performance of WSS similar to conventional synchronous generators. This paper proposes a PFC for WSS with a prediction-based droop coefficient (PDC) according to the re-bid process under real-time spot market rules. Specifically, WSS update the values of the reference power and droop coefficient discretely at every bidding interval using near-term wind power and frequency prediction, which enables WSS to be more dispatchable in the view of transmission system operators (TSOs). Also, the accurate prediction method in the proposed PDC-PFC achieves the optimal arrangement of power from WTG and BESS in PFC. Finally, promising simulation results for a hybrid power system show the efficacy of the proposed PDC-PFC for WSS under different operating conditions.

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Tansakul, C., S. Laborie, and C. Cabassud. "Study on performance of ultrafiltration membrane-based pretreatment for application to seawater reverse osmosis desalination." Water Science and Technology 62, no. 9 (November 1, 2010): 1984–90. http://dx.doi.org/10.2166/wst.2010.483.

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The objective of the work was to study at lab-scale the efficiency of hybrid process- coupling powdered activated carbon (PAC) adsorption or FeCl3 coagulation and UF- for marine organic matter removal. Regenerated cellulose membrane with 30 kDa and actual seawater from Mediterranean Sea were used. The coagulant was FeCl3 and adsorbents were two PAC types, with different surface area and pore size distribution. The results showed that PAC adsorption/UF performed higher efficiency in terms of organic removal than FeCl3 coagulation/UF. Organic matter removal up to 50% was obtained for a PAC dose of 200 mg/L. According to high performance size exclusion chromatography (HP-SEC) analysis, the organics removed by PAC/UF are approximately 10 kDa. Therefore, the effect of PAC adsorption was deeply evaluated in terms of UF membrane fouling rate. The fouling rate was reduced when increasing PAC dose for both PAC types, in particular when PAC with a higher BET surface area and larger fraction of micropores was used. On the other hand, the results showed that UF unit could highly reduce SDI3 from 26 to 9. The addition of PAC and FeCl3 to UF allowed a further reduction of SDI3 from 9 to 4–6.

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Song, Hongzhan, Shangsheng Wen, Chen Yang, Danlan Yuan, and Weipeng Guan. "Universal and Effective Decoding Scheme for Visible Light Positioning Based on Optical Camera Communication." Electronics 10, no. 16 (August 10, 2021): 1925. http://dx.doi.org/10.3390/electronics10161925.

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As a promising approach to implement indoor positioning, visible light positioning (VLP) based on optical camera communication (OCC) image sensor has attracted substantial attention. However, the decoding schemes of existing VLP systems still face many challenges. First, the transmission channel between transmitters and receivers can be easily affected by environmental changes, resulting in poor thresholding performance. Second, the inherently unsynchronized air transmission channel issue remains a big obstacle for decoding data. The above two problems limit the application of VLP systems, where various mobile devices are used as receivers and the properties of transmission channel are constantly changing with the movement of receivers. In this paper, a universal and effective decoding scheme named pixel-to-bit calculation (PBC) decoding algorithm for VLP systems is proposed and experimentally demonstrated. It includes a Staged Threshold Scheme which provides excellent thresholding performance for different transmission channel conditions, as well as a Synchronous Decoding Operation to automatically synchronize the clock between transmitters and receivers. A decoding rate of 95.62% at the height of 2.73 m is realized in a practical Robotic-based VLP system embedded with our proposed PBC decoding scheme. In addition, experimental results show that the average decoding rate of the proposed PBC decoding scheme reaches 99.9% when applying different transmitters and receivers.

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Califano, Valeria, Aniello Costantini, Brigida Silvestri, Virginia Venezia, Stefano Cimino, and Filomena Sannino. "The effect of pore morphology on the catalytic performance of β-glucosidase immobilized into mesoporous silica." Pure and Applied Chemistry 91, no. 10 (October 25, 2019): 1583–92. http://dx.doi.org/10.1515/pac-2018-1202.

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Abstract β-Glucosidase (BG) was immobilized by adsorption on wrinkled silica nanoparticles (WSNs) and on tannic acid-templated mesoporous silica nanoparticles (TA-MSNPs). The effect induced by a different morphology of the pores of the sorbent on the catalytic performance of β-glucosidase was investigated. A complete textural and morphological characterization of the two samples was performed by Brunauer–Emmett–Teller (BET) method, Fourier Transform Infrared (FT-IR) and transmission electron microscopy (TEM). The results demonstrated that the catalytic performance of the immobilized enzyme depends on the pores size of sorbent but a key factor is the pores morphology. In fact, the BG immobilized on WSNs and TA-MSNPs (BG/WSNs and BG/TA-MSNPs) shows in both cases good catalytic performances in cellobiose hydrolysis, but the catalyst with the best performance is BG/WSNs, in which the support exhibits a central-radial pore structure and a hierarchical trimodal micro-mesoporous pore size. This peculiar morphology allows the enzyme to settle in a place where the interactions with the walls are maximized, increasing its conformational rigidity. Furthermore, the enzyme is prevalently collocated in the interior of pore so that the pores are not completely capped.

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Gül, Ş., O. Eren, Ş. Kır, and Y. Önal. "A comparison of different activated carbon performances on catalytic ozonation of a model azo reactive dye." Water Science and Technology 66, no. 1 (July 1, 2012): 179–84. http://dx.doi.org/10.2166/wst.2012.103.

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The objective of this study is to compare the performances of catalytic ozonation processes of two activated carbons prepared from olive stone (ACOS) and apricot stone (ACAS) with commercial ones (granular activated carbon-GAC and powder activated carbon-PAC) in degradation of reactive azo dye (Reactive Red 195). The optimum conditions (solution pH and amount of catalyst) were investigated by using absorbencies at 532, 220 and 280 nm wavelengths. Pore properties of the activated carbon (AC) such as BET surface area, pore volume, pore size distribution, and pore diameter were characterized by N2 adsorption. The highest BET surface area carbon (1,275 m2/g) was obtained from ACOS with a particle size of 2.29 nm. After 2 min of catalytic ozonation, decolorization performances of ACOS and ACAS (90.4 and 91.3%, respectively) were better than that of GAC and PAC (84.6 and 81.2%, respectively). Experimental results showed that production of porous ACs with high surface area from olive and apricot stones is feasible in Turkey.

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Wei, Chuanying, Haili Hou, Ermo Wang, and Min Lu. "Preparation of a Series of Pd@UIO-66 by a Double-Solvent Method and Its Catalytic Performance for Toluene Oxidation." Materials 13, no. 1 (December 23, 2019): 88. http://dx.doi.org/10.3390/ma13010088.

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This paper reports on the preparation, characterization, and catalytic properties of the Pd@UIO-66 for toluene oxidation. The samples are prepared by the double-solvent method to form catalysts with large specific surface area, highly dispersed Pd0 (Elemental palladium) and abundant adsorbed oxygen, which are characterized by X-ray Photoelectron Spectroscopy (XPS), Brunauer-Emmett-Teller (BET) and Transmission Electron Microscopy (TEM). The results show that as the Pd content increases, the adsorbed oxygen content further increases, but at the same time Pd0 will agglomerate and lose some active sites, which will affect its catalytic performance. While 0.2%Pd@UIO-66 has the highest concentration of Pd0, the result shows it has the best catalytic activity and the T90 temperature is 210 °C.

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Yao, Sicong, Meicheng Wang, Jilong Liu, Shuxiong Tang, Hengli Chen, Tiecheng Guo, Ge Yang, and Yao Chen. "Removal of phosphate from aqueous solution by sewage sludge-based activated carbon loaded with pyrolusite." Journal of Water Reuse and Desalination 8, no. 2 (December 11, 2017): 192–201. http://dx.doi.org/10.2166/wrd.2017.054.

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Abstract Activated carbons were prepared from sewage sludge by chemical activation with pyrolusite (PAC) to develop an efficient adsorbent for phosphate removal from aqueous solution. One percent (wt.) pyrolusite addition was proved to have an important effect on pore formation of the produced carbon. PAC showed 17.06% larger Brunauer–Emmett–Teller (BET) surface area than the sewage sludge-based activated carbon without modification (SAC). The adsorption results showed that the phosphate removal by PAC was 13% higher than SAC's. The adsorption experiments also showed that PAC had very good performance with high phosphate removal rate (ca. 90%) in a wide pH range (pH = 4–8), and could be stable after 30 min reaction. Adsorption isotherm and kinetics studies demonstrated that phosphate adsorption onto the modified adsorbent was well fitted by the Langmuir isotherm and could be described by the pseudo-second-order kinetic model. The modified sewage sludge-based activated carbons were effective and alternative adsorbents for the removal of phosphorus from aqueous solution due to their considerable adsorptive capacities and the low-cost renewable sources.

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Mollaei, Masoume, Mazaher Moeinaddini, Nematollah Khorasani, Mohammad Azadfallah, and Amirhooman Hemmasi. "Feasibility of removal S−2 from Kraft black liquor recovery cycle with synthetic adsorbents (Cu-PAC and Cu-GAC)." Nordic Pulp & Paper Research Journal 35, no. 3 (September 25, 2020): 309–24. http://dx.doi.org/10.1515/npprj-2019-0091.

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AbstractSulfide ions (S−2) derived from Na2S in black liquor, after the pulping process, is the source of production H2S during of black liquor recovery cycle in Kraft pulp and paper industries. Tow adsorbents (Cu-PAC, Cu-GAC) by loading Cu+2 on powder activated carbon (PAC) and granular activated carbon (GAC) were synthesized to created more adsorption sites and were improved their selectivity for removing S−2 from black liquor with 3 level of sulfidity (18, 20 and 22 %). The adsorbents were characterized by BET, FTIR, SEM, and EDX. Adsorption of S−2 for Cu-PAC and Cu-GAC were fitted well with Freundlich and Langmuir isotherm model respectively and both of the adsorbents followed pseudo-second-order kinetic. The results of thermodynamic parameters showed the endothermic process. The removal efficiency results showed Cu-PAC has better performance than Cu-GAC. This is due to the higher specific surface area of Cu-PAC, which has led to more adsorption sites for S−2. By considering appropriate temperature conditions and direct effect of the S−2 on the production of H2S during of black liquor recovery cycle, Cu-PAC will be able to prevent H2S production and odorous the black liquor recovery cycle by removing 79.89 % of the S−2.

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Li Chao, 李超, 张文博 Zhang Wenbo, 张晓光 Zhang Xiaoguang, 席丽霞 Xi Lixia, 唐先锋 Tang Xianfeng, and 何文雪 He Wenxue. "Performance Enhancement of LDPC in 100 Gb/s PDM-DQPSK Optical Communication Using a Water-Bit Based on Channel Estimation." Chinese Journal of Lasers 41, no. 6 (2014): 0605007. http://dx.doi.org/10.3788/cjl201441.0605007.

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Liu, Zheng, and Yuling Wei. "K2CO3-Activated Pomelo Peels as a High-Performance Adsorbent for Removal of Cu(II): Preparation, Characterization, and Adsorption Studies." Journal of Chemistry 2021 (June 15, 2021): 1–11. http://dx.doi.org/10.1155/2021/9940577.

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Activated carbons (ACs) were prepared from pomelo peels by K2CO3 activation and used as an adsorbent (PAC) for the removal of Cu(II) from aqueous solutions. BET, SEM, and FT-IR were employed for the characterization of the obtained ACs. The optimum ACs were reported at activation temperature of 850°C, activation time of 60 min, and impregnation ratio of 3, which had a high surface area (1213 m2/g) and total pore volume (0.57 cm3/g). The resulting ACs were used for the adsorption of Cu(II) from aqueous solutions in the batch mode and yielded a superior adsorption capacity of 139.08 mg/g. The pH of optimum adsorption was determined as 5. Pseudo first-order model, pseudo second-order model, and intraparticle diffusion model were applied to describe the adsorption processes. The adsorption kinetic data were found to follow the pseudo second-order model. The adsorption isotherms data were analyzed using Langmuir, Freundlich, Temkin, and Dubinin–Radushkevich models. The Langmuir model was found to provide the best fit, and the calculated adsorption capacity was 151.35 mg/g.

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Eghbali, Paria, Bilal Nişancı, and Önder Metin. "Graphene hydrogel supported palladium nanoparticles as an efficient and reusable heterogeneous catalysts in the transfer hydrogenation of nitroarenes using ammonia borane as a hydrogen source." Pure and Applied Chemistry 90, no. 2 (February 23, 2018): 327–35. http://dx.doi.org/10.1515/pac-2017-0714.

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Abstract Addressed herein is a facile one-pot synthesis of graphene hydrogel (GHJ) supported Pd nanoparticles (NPs), namely Pd-GHJ nanocomposites, via a novel method that comprises the combination of hydrothermal treatment and polyol reduction protocols in water. The structure Pd-GHJ nanocomposites were characterized by TEM, HR-TEM, XRD, XPS, Raman spectroscopy and BET surface area analysis. Then, Pd-GHJ nanocomposites were used as a heterogeneous catalysts in the tandem dehydrogenation of ammonia borane and hydrogenation of nitroarenes (Ar–NO2) to anilines (Ar–NH2) in the water/methanol mixture at room temperature. A variety of Ar–NO2 derivatives (total 9 examples) were successfully converted to the corresponding Ar–NH2 by the help of Pd-GHJ nanocomposites catalyzed tandem reactions with the conversion yields reaching up to 99% in only 20 min reaction time. Moreover, Pd-GHJ nanocomposites were demonstrated to be the reusable catalysts in the tandem reactions by preserving their initial catalytic performance after five consecutive catalytic cycles. It is believed that the presented synthesis protocol for the Pd-GHJ nanocomposites and the catalytic tandem hydrogenation reactions will make a significant contribution to the catalysis and synthetic organic chemistry fields.

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Kindler, Hedy L., Pascal Hammel, Michele Reni, Eric Van Cutsem, Teresa Macarulla Mercade, Michael J. Hall, Joon Oh Park, et al. "Olaparib as maintenance treatment following first-line platinum-based chemotherapy (PBC) in patients (pts) with a germline BRCA mutation and metastatic pancreatic cancer (mPC): Phase III POLO trial." Journal of Clinical Oncology 37, no. 18_suppl (June 20, 2019): LBA4. http://dx.doi.org/10.1200/jco.2019.37.18_suppl.lba4.

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LBA4 Background: Pancreatic cancer (PC) pts with a germline BRCA1 and/or BRCA2 mutation (gBRCAm) have shown response to the PARP inhibitor olaparib (Kaufman 2015). POLO is the first phase III trial to evaluate efficacy of maintenance treatment with a PARP inhibitor in PC. Methods: POLO is an international, randomized, double-blind, placebo-controlled trial of pts with a gBRCAm and pancreatic adenocarcinoma who had received ≥16 weeks of first-line PBC for metastatic disease without progression. Pts were randomized 3:2 to maintenance olaparib (O) tablets (300 mg bid) or placebo (P). Treatment began 4–8 weeks after last PBC dose, continuing until investigator-assessed progression or unacceptable toxicity. The primary endpoint was progression-free survival (PFS) by blinded independent central review (modified RECIST 1.1). Results: We screened 3315 pts, identified 247 with a gBRCAm, randomized 154 (O 92, P 62), and treated 151 (O 90, P 61). Pt characteristics (O/P): age, median (range) 57 (37–84)/57 (36–75); male, 58%/50%; ECOG performance status 0, 71%/61%. With 104 events, PFS was significantly improved with O vs. P (hazard ratio [HR] 0.53; 95% CI 0.35, 0.82; p = 0.0038; median PFS was 7.4 vs. 3.8 months [mo], respectively) and consistent irrespective of response to prior PBC (complete/partial HR 0.62; stable disease HR 0.50). From 6 mo, the % of pts progression-free in the O arm was more than twice that in the P arm (Table). At the interim overall survival analysis (46% maturity), HR was 0.91 (95% CI 0.56, 1.46; p = 0.68). Grade ≥3 adverse events (AE) occurred in 40% of O- and 23% of P-treated pts; 5.5% and 1.7% of pts, respectively, discontinued treatment due to an AE. Conclusions: Maintenance olaparib provided a statistically significant and clinically meaningful improvement in PFS in mPC pts with a gBRCAm who had not progressed on PBC. Safety was consistent with the known profile for olaparib. POLO is the first phase III trial to validate a biomarker-driven treatment in PC. Clinical trial information: NCT02184195. [Table: see text]

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Juwono, Hendro, Triyono Triyono, Sutarno Sutarno, Endang Tri Wahyuni, Harmami Harmami, Ita Ulfin, and Fredy Kurniawan. "Production of Hydrocarbon (C7-C20) from Hydrocracking of Fatty Acid Methyl Esters on Pd/Al-MCM-41 Catalyst." Bulletin of Chemical Reaction Engineering & Catalysis 12, no. 3 (October 28, 2017): 337. http://dx.doi.org/10.9767/bcrec.12.3.811.337-342.

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The production of hydrocarbon (C7-C20) and alcohol (C11-C19) from fatty acid methyl esters (FAMEs) compound are produced from the transesterification of the seed oil of the Nyamplung that has been conducted by the catalytic hydrocracking using Al-MCM-41 and Pd2+-impregnated-Al-MCM-41 catalysts. The performance of catalysts were compared by various analysis including the acidity that was determined by pyridine and FTIR, the crystal structure observed by XRD, the surface area and pore volume analyzed by BET/BJH, the surface morphology observed by TEM, the metal on the surface of catalyst observed by XPS and the product of the hydrocracking analyzed by GC-MS. Hexagonal structure of the MCM-41(100) was shown in the 2θ = 3o-5o of the diffractogram. The presence of impregnated Al and Pd observed at the 2θ = 20o and 34o, respectively. The Pd/Al-MCM-41 catalyst was more acidic than Al-MCM-41 catalyst. The surface area and pore volume of the catalyst decreased after the impregnation process. The tendency of catalytic hydrocracking of hydrocarbon produced was indicated that more amount of Palladium have more hydrocarbons aliphatic than alcohol. Copyright © 2017 BCREC Group. All rights reservedReceived: 21st November 2016; Revised: 24th May 2017; Accepted: 25th May 2017; Available online: 27th October 2017; Published regularly: December 2017How to Cite: Juwono, H., Triyono, T., Sutarno, S., Wahyuni, E.T., Harmami, H., Ulfin, I., Kurniawan, F. (2017). Production of Hydrocarbon (C7-C20) from Hydrocracking of Fatty Acid Methyl Esters on Pd/Al-MCM-41 Catalyst. Bulletin of Chemical Reaction Engineering & Catalysis, 12 (3): 337-342 (doi:10.9767/bcrec.12.3.811.337-342)

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Rutkauskienė, Ugnė. "Viešųjų bibliotekų poveikio vertinimas." Informacijos mokslai 46 (January 1, 2008): 84–101. http://dx.doi.org/10.15388/im.2008.0.3355.

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Atsiradus įtampai viešojo sektoriaus finansavimo srityje bei didėjant visuomenės reikalavimams, keliamiems mokesčių mokėtojų lėšomis išlaikomoms institucijoms, bibliotekos turi parodyti, kokią naudą duoda jų teikiamos paslaugos. Šie rezultatai gali būti iliustruojami bibliotekų statistiniais duomenimis, liudijančiais, kokia yra paslaugų paklausa, naudojamumas, kokybę apibrėžiančiais rodikliais ar tyrimų išvadomis, kurios parodo vartotojų pasitenkinimą, tačiau nei vieni iš paminėtų dar neįrodo teigiamo bibliotekų poveikio individams ir bendruomenėms. Siekdamos atsakyti į šį klausimą, itin dominantį tiek visuomenę, tiek finansuojančias institucijas, bibliotekos turėtų vertinti ne tik savo veiklą, bet ir jos pasekmes, susijusias su bibliotekų verte, poveikiu lankytojams bei visuomenei. Straipsnyje aptariami bibliotekų poveikio vertinimo klausimai, išsamiau nagrinėjamas vienos iš bibliotekų paslaugų – viešos interneto prieigos – poveikio vertinimas bei pristatomas Lietuvos viešosioms bibliotekoms siūlomas poveikio vertinimo modelis.Pagrindiniai žodžiai: poveikio vertinimas, viešosios bibliotekos, vertė, vieša interneto prieiga, projektas „Bibliotekos pažangai“Public libraries impact measuresUgnė Rutkauskienė SummaryRecent years were very challenging for most of public libraries. Due to the financial tension in public administration budgets many of them experienced heavy financial cuts. Both financial pressure from local authorities and growing demands for pubic accountability sets new gals for libraries performance measurement. There is a clear need for data, proving positive impact of libraries on individuals and communities.The goal of this paper is to demonstrate the importance of impact and outcome research in public libraries. The paper gives an overview of purposes and methods used in impact studies and illustrate this through research experiences. It also presents impact assessment model of “Libraries for Innovations” project.One of the main identified problems of the impact focused research is that it is very tightly related with the influences on individuals so it is very difficult to trace changes and improvements back to the library. Other methodological challenges of measuring the impact of PAC in libraries’ include a multi-methodological orientation; a balance between process and outcome analyzes; a combination of both primary and secondary source data; an emphasis on triangulation of research data; an observation of the same items over long periods of time.The paper acquaints libraries with a topic that is not yet well known and, by showing practical examples, demonstrates how libraries can attempt to assess the impact of public access computing.

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Najm, A., A. Alunno, X. Mariette, B. Terrier, G. De Marco, L. Mason, J. Emmel, D. Mcgonagle, and P. M. Machado. "POS0052 PATHOPHYSIOLOGY OF ACUTE RESPIRATORY SYNDROME CORONAVIRUS 2 INFECTION: A SYSTEMATIC LITERATURE REVIEW TO INFORM EULAR POINTS TO CONSIDER." Annals of the Rheumatic Diseases 80, Suppl 1 (May 19, 2021): 231–32. http://dx.doi.org/10.1136/annrheumdis-2021-eular.2851.

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Background:The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic is a global health problem. Beside the specific pathogenic effect of SARS-CoV-2, incompletely understood deleterious and aberrant host immune responses play critical roles in severe disease. Rheumatologists have the best experience of studying and treating these complicated hyperinflammatory processes.Objectives:To summarize the available information on pathophysiology of COVID-19.Methods:As part of a EULAR taskforce, two systematic literature reviews were performed one on pathophysiology and one on immunomodulatory therapies. Two reviewers independently identified eligible studies according to the following PICO framework: P (population): patients with SARS-CoV-2 infection; I (intervention): any intervention/no intervention; C (comparator): any comparator; O (outcome) any clinical or serological outcome including but not limited to immune cell phenotype and function and serum cytokine concentration. The results pertaining to pathophysiology of COVID-19 are presented here.Results:Of the 55496 records yielded, 85 articles were eligible for inclusion. Included studies were at variable risk of bias and exploring various aspects of disease pathogenesis from immune to non-immune cells (Table 1). Pro-inflammatory cytokines’ expression including IL-6, was increased, especially in severe COVID-19, although not as high as other states with severe systemic inflammation. Innate and adaptative immune cell compartments were differentially affected by SARS-CoV-2 infection: neutrophils displayed an immature differentiation state and also increased neutrophil extracellular traps (NETs) formation. Dendritic cell number was reduced and classical monocytes was increased although displaying a reduced expression of HLA-DR. The lymphoid compartment was also affected: lymphopenia was present with a reduced number of CD4+ and CD8+ T lymphocytes and more frequent PD1+CD8+ T cells corresponding to an exhausted phenotype. Antibody response to SARS-CoV-2 infection showed a high variability across individuals and disease spectrum. Multiparametric algorithms showed variable diagnostic performances in predicting survival, hospitalization, disease progression or severity, and mortality. Differences in SARS-CoV-2 manifestations in adults and children were highlighted.Conclusion:Overall, SARS-CoV-2 infection affects both innate and adaptative immune responses in a variable way, according to both disease severity and individual parameters. This SLR informs the EULAR points to consider on pathophysiology and use of immunomodulatory therapies in COVID-19.Table 1.Studies on SARS-CoV-2 infection pathogenesisResearch questionNCytokines profile7Immune profile18Algorithm17Children3Comorbidities1Endothelial dysfunction and platelets8Gut and microbiota3Genetics and variants8Histology7Antibodies profiles8Viral load and immune response4Interferon3Immunosenecsnce3Total90**Some manuscripts were including in several research questions. Total number of studies included n=85.Disclosure of Interests:Aurelie Najm Speakers bureau: BMS, Consultant of: BMS, Alessia Alunno: None declared, Xavier Mariette Speakers bureau: BMS, Eli Lilly, Galapagos, Gilead, GSK, Janssen, Novartis, Pfizer, Servier and UCB, Consultant of: BMS, Eli Lilly, Galapagos, Gilead, GSK, Janssen, Novartis, Pfizer, Servier and UCB, Benjamin Terrier Speakers bureau: Roche, Chugai, Vifor Pharma, GSK, AstraZeneca, Terumo BCT, LFB and Grifols, Consultant of: Roche, Chugai, Vifor Pharma, GSK, AstraZeneca, Terumo BCT, LFB and Grifols, Gabriele De Marco: None declared, Laura Mason: None declared, Jenny Emmel: None declared, Dennis McGonagle Speakers bureau: Abbvie, BMS, Celgene, Eli Lilly, Janssen, MSD, Novartis, Pfizer, Roche and UCB, Consultant of: Abbvie, BMS, Celgene, Eli Lilly, Janssen, MSD, Novartis, Pfizer, Roche and UCB, Pedro M Machado Speakers bureau: Abbvie, BMS, Celgene, Eli Lilly, Janssen, MSD, Novartis, Orphazyme, Pfizer, Roche and UCB, Consultant of: Abbvie, BMS, Celgene, Eli Lilly, Janssen, MSD, Novartis, Orphazyme, Pfizer, Roche and UCB.

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Harbi, Samia, Raynier Devillier, Sabine Furst, Luca Castagna, Angela Granata, Faezeh Legrand, Thomas Pagliardini, et al. "Allogeneic Hematopoietic Stem Cell Transplantation in Patients of 65 Years or Older: A Monocenter Analysis on 252 Patients." Blood 134, Supplement_1 (November 13, 2019): 4625. http://dx.doi.org/10.1182/blood-2019-131845.

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Advanced hematologic malignancies in older patients are unmet medical needs due to increased incidence in the aging population and the lack of effective treatment. Allogeneic hematopoietic stem cell transplantation (allo-HSCT) represents the only potential curative option for most of hematologic malignancies. However, two main limitations limited this development for a long period of time. High rates of fatal non-relapse morbidities have been progressively addressed using reduced toxicity conditioning approaches and pushing up the age limit of patients considered for transplant. The search for a donor has been also a high limitation in older population, due to the lower incidence of matched sibling donors in this population. The development of allo-HSCT from a familial haplo mismatch donor (Haplo donor) after a reduced intensity (RIC) or non-myeloablative conditioning (NMAC) has allowed for the recent development of allo-HSCT in older population. Here we analyzed a cohort of 252 consecutive patients aged of 65 years or older treated in a single institution. Patients were selected on the following parameters: age of 65 or older on the day of transplant, first allogeneic transplant, no unrelated cord blood HSCT, hematologic malignancies, transplant between 01/01/2004 and 31/12/2018. During this period of time, the search for a one-mismatch haplotype donor (Haplo) has been introduced, the upper limit age for transplant progressively increased, more advanced diseases were considered and patients have gradually benefit from improvement in transplant care. Patient characteristics: Median age: 67,9 (65-77) years; Male patients: 61 %; CMV Positive (70%); Acute leukemia (AL): 43%; Myelodysplastic/myeloproliferative syndromes (MDS/MPS): 35%; Chronic Leukemia: 5%; Lymphoma: 11%; Plasma cell disorders (PCD): 6%. Complete remission (CR) or Chronic phase: 155 (62%) (of whom 81 CR1 AL) Donor characteristics: median age: 62,45 (19-77); Male patients: 63 %; Matched sibling donor (MSD) (24%): 60: Unrelated donor: 75 (29%); Haplo Donor: 118 (47%). Transplant characteristics: % patients per period of time: year range: 2004-2010: 12% (Median age: 67; % Haplo D: 0; No CR/CP: 23%); 2011-2015: 40% (Median age: 68; % Haplo D: 35%; No CR/CP: 39%); 2016-2018: 48% (Median age: 69; % Haplo D: 69%; No CR/CP: 42%); PBSC: 97%; Non Myeloablative/ Reduced toxicity conditioning: 35%/65%; All patients received Post-Transplant (PostT) CSA; PT Cyclophosphamide: 49%; Pre-Transplant ATG: 47%. Median follow-up: 17 (3-112) months; ANC recovery in 96%: 19 (10-44) days; untransfused platelet recovery above 20 in 75%: 17 (7-56) days. In evaluable patients for aGVHD: No: 58%; Grade 1: 13%; Grade 2: 14%; Grade 3: 10%; Grade 4: 4%; 85% patients were evaluable for cGVHD: No: 68%; limited: 17%; extensive:16%; 64 patients (25%) patients died from non-relapse mortality at a median of 122 days (13-3934): 2004-2010: 10/30 (33%); 2011-2015: 36/101 (25%); 2016-2018: 28/121 (23%); 53 patients relapsed/progressed at a median of 252 (30-2764) days. Three year overall and disease-free survivals are respectively of 56% (95% CI: 6.35-7.04) and 47% (95% CI: 7.17-7.55) without any difference according to age or donor type but with an impact of disease status (EFS: CR/CP 51% (95% CI: 8.7-9.5) vs others 38% ((95% CI: 11.9-12.0)) Overall these data show that allo HSCT is a valid option in older patients with high-risk malignancies. They show also that over a long period of time patient typology (more advanced diseases, older patients) and transplant practice (lower number of MSD) show a regular evolution making transplant realization more challenging. This field needs specific approach taking into account comorbidities, performance status and geriatric evaluation, to adapt treatment to every given patient. In this perspective we performed from 2015 in patients older than 65 years systematic and combined evaluation of comorbidities score, performance status and geriatric assessment (instrumental activity of daily living (AIDL); vulnerability assessment). Disclosures Chabannon: Sanofi SA: Other: research support, speaker's fees, hospitalities; Gilead: Other: speaker's fees, hospitalities; Novartis: Other: speaker's fees; Celgene: Other: speaker's fees; Terumo BCT: Other: speaker's fees; Miltenyi Biotech: Other: research support; Fresenius Kabi: Other: research support; EBMT: Other: Working Party Chair, Board member. Vey:Janssen: Honoraria; Novartis: Consultancy, Honoraria. Blaise:Jazz Pharmaceuticals: Honoraria; Sanofi: Honoraria; Pierre Fabre medicaments: Honoraria; Molmed: Consultancy, Honoraria.

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K K A, Abdullah, Robert A B C, and Adeyemo A B. "August 2016 VOLUME 5, ISSUE 8, AUGUST 2016 5th Generation Wi-Fi Shatha Ghazal, Raina S Alkhlailah Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5801 ECG Arrhythmia Detection Using Choi-Williams Time-Frequency Distribution and Artificial Neural Network Sanjit K. Dash, G. Sasibhushana Rao Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5802 Data Security using RSA Algorithm in Cloud Computing Santosh Kumar Singh, Dr. P.K. Manjhi, Dr. R.K. Tiwari Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5803 Detection Algorithms in Medical Imaging Priyanka Pareek, Pankaj Dalal Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5804 A Review Study on the CPU Scheduling Algorithms Shweta Jain, Dr. Saurabh Jain Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5805 Healthcare Biosensors - A Paradigm Shift To Wireless Technology Taha Mukhtar Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5806 Congestion Control for Peer to Peer Application using Random Early Detection Algorithm Sonam Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5807 Quantitative and Qualitative Analysis of Milk Parameters using Arduino Controller Y.R. Bhamare, M.B. Matsagar, C.G. Dighavkar Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5808 Ardunio Based Security and Safety using GSM as Fault Alert System for BTS (Base Transceiver Station) Umeshwari Khot, Prof. Venkat N. Ghodke Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5809 Automatic Single and Multi Topic Summarization and Evolution to Generate Timeline Mrs. V. Meenakshi, Ms. S. Jeyanthi Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5810 Data Hiding in Encrypted HEVC/AVC Video Streams Saltanat Shaikh, Prof. Shahzia Sayyad Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5811 A Study of Imbalanced Classification Problem P. Rajeshwari, D. Maheshwari Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5812 Design of PTL based Area Efficient and Low Power 4-bit ALU Saraabu Narendra Achari, Mr. C. Pakkiraiah Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5813 The Design of Driver Safety Awareness and Assistance System through Sleep Activated and Auto Brake System for Vehicle Control D. Sivabalaselvamani, Dr. A. Tamilarasi, L. Rahunathan and A.S. Harishankher Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5814 Parameters Selection, Applications & Convergence Analysis of PSO Algorithms Sachin Kumar, Mr. N.K. Gupta Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5815 Effective Pattern Deploying Model for the Document Restructuring and Classification Niketa, Jharna Chopra Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5816 Cataloging Telugu Sentences by Hidden Morkov Techniques V. Suresh Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5817 Biometrics for Cell Phone Safety Jyoti Tiwari, Santosh Kumar Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5818 Digital Image Watermarking using Modified DWT&DCT Combination and Bi Linear Interpolation Yannam .Nagarjuna, K. Chaitanya Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5819 Comparative Study and Analysis on the Techniques of Web Mining Dipika Sahu, Yamini Chouhan Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5820 A Review of MIL-STD-1553 Bus Trends and Future K. Padmanabham, Prabhakar Kanugo, Dr. K. Nagabhushan Raju, M. Chandrashekar Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5821 Design of QPSK Digital Modulation Scheme Using Turbo Codes for an Air Borne System D. Sai Brunda, B. Geetha Rani Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5822 An Efficient Locally Weighted Spectral Cluster for Automatic Image Segmentation Vishnu Priya M, J Santhosh Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5823 An Efficient Sliding Window Based Micro Cluster Over Data Streams Nancy Mary, A. Venugopal Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5824 Comparative Analysis of Traditional Frequency Reuse Techniques in LTE Network Neelam Rani, Dr. Sanjeev Kumar Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5825 Score Level Integration of Fingerprint and Hand Geometry Biometrics Jyoti Tiwari, Santosh Kumar Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5826 CHARM: Intelligently Cost and Bandwidth Detection for FTP Servers using Heuristic Algorithm Shiva Urolagin Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5827 Image Enhancement Using Modified Exposure Based Histogram SK. Nasreen, N. Anupama Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5828 Human Gesture Based Recognition and Classification Using MATLAB Suman, Er. Kapil Sirohi Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5829 Image Denoising- A Novel Approach Dipali D. Sathe, Prof. K.N. Barbole Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5830 Design of Low Pass Digital FIR Filter Using Nature Inspired Technique Nisha Rani, Balraj Singh, Darshan Singh Sidhu Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5831 Issues and Challenges in Software Quality Assurance Himangi, Surender singh Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5832 Hybridization of GSA and AFSA to Detect Black Hole Attack in Wireless Sensor Network Soni Rani, Charanjit Singh Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5833 Reversible Watermarking Technique for Data Hiding, Accurate Tamper Detection in ROI and Exact Recovery of ROI Y. Usha Madhuri, K. Chaitanya Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5834 Fault Tolerance and Concurrency Control in Heterogeneous Distributed Database Systems Sagar Patel, Meghna Burli, Nidhi Shah, Prof. (Mrs.) Vinaya Sawant Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5835 Collection of Offline Tamil Handwriting Samples and Database Creation D. Rajalakshmi, Dr. S.K. Jayanthi Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5836 Overview of Renewable Energy in Maharashtra Mr. Sagar P. Thombare, Mr. Vishal Gunjal, Miss. Snehal Bhandarkar Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5837 Comparative Analysis of Efficient Image Steganographic Technique with the 2-bit LSB Algorithm for Color Images K. S. Sadasiva Rao, Dr A. Damodaram Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5838 An Efficient Reverse Converter Design for Five Moduli Set RNS Y. Ayyavaru Reddy, B. Sekhar Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5839 VLSI Design of Area Efficient High Performance SPMV Accelerator using VBW-CBQCSR Scheme N. Narasimharao, A. Mallaiah Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5840 Customer Retention of MCDR using 3SCDM Approaches Suban Ravichandran, Chandrasekaran Ramasamy Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5841 User Privacy and Data Trustworthiness in Mobile Crowd Sensing Ms. T. Sharadha, Dr. R. Vijaya Bhanu Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5842 A Safe Anti-Conspiracy Data Model For Changing Groups in Cloud G. Ajay Kumar, Devaraj Verma C Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5843 Scope and Adoption of M-Commerce in India Anurag Mishra, Sanjay Medhavi, Khan Shah Mohd, P.C. Mishra Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5844 A Secure Data Hiding Scheme For Color Image Mrs. S.A. Bhavani Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5845 A Study of Different Content Based Image Retrieval Techniques C. Gururaj, D. Jayadevappa, Satish Tunga Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5846 Cache Management for Big Data Applications: Survey Kiran Grover, Surender Singh Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5847 Survey on Energy Efficient Protocols and Challenges in IOT Syeda Butool Fatima, Sayyada Fahmeeda Sultana, Sadiya Ansari Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5848 Educational Data Mining For Evaluating Students Performance Sampreethi P.K, VR. Nagarajan Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5849 Iterative Pareto Principle for Software Test Case Prioritization Manas Kumar Yogi, G. Vijay Kumar, D. Uma Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5850 Localization Techniques in Wireless Sensor Networks: A Review Abhishek Kumar, Deepak Prashar Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5851 Ensemble Averaging Filter for Noise Reduction Tom Thomas Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5852 Survey Paper on Get My Route Application Shubham A. Purohit, Tushar R. Khandare, Prof. Swapnil V. Deshmukh Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5853 Design and Implementation of Smart Car with Self-Navigation and Self-Parking Systems using Sensors and RFID Technology Madhuri M. Bijamwar, Prof. S.G. Kole, Prof. S.S. Savkare Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5854 Comparison Study of Induction Motor Drives using Microcontroller and FPGA Sooraj M S, Sreerag K T V Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5855 A Survey on Text Categorization Senthil Kumar B, Bhavitha Varma E Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5856 Multirate Signal Reconstruction Using Two Channel Orthogonal Filter Bank Sijo Thomas, Darsana P Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5857 The Multi-keyword Synonym Search for Encrypted Cloud Data Using Clustering Method Monika Rani H G, Varshini Vidyadhar Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5858 A Review on Various Speech Enhancement Techniques Alugonda Rajani, Soundarya .S.V.S Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5859 A Survey on Various Spoofing Attacks and Image Fusion Techniques Pravallika .P, Dr. K. Satya Prasad Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5860 Non-Invasive Vein Detection using Infra-red Rays Aradhana Singh, Dr. S.C. Prasanna Kumar, Dr. B.G. Sudershan Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5861 Boundary-Polygons for Minutiae based Fingerprinst Recognition Kusha Maharshi, Prashant Sahai Saxena Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5862 Image Forgery Detection on Digital Images Nimi Susan Saji, Ranjitha Rajan Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5863 Enhancing Information Security in Big Data Renu Kesharwani Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5864 Secure Multi-Owner Data Sharing for Dynamic Groups in Cloud Ms. Nilophar M. Masuldar, Prof. V. P. Kshirsagar Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5865 Compact Microstrip Octagonal Slot Antenna for Wireless Communication Applications Thasneem .H, Midhun Joy Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5866 ‘Aquarius’- Smart IOT Technology for Water Level Monitoring System Prof. A. M. Jagtap, Bhaldar Saniya Sikandar, Shinde Sharmila Shivaji, Khalate Vrushali Pramod, Nirmal Kalyani Sarangdhar Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5867 Future of Results in Select Search Engine Peerzada Mohammad Iqbal, Dr. Abdul Majid Baba, Aasim Bashir Abstract | PDF with Text | DOI: 10.17148/IJARCCE.2016.5868 Semantic Indexing Techniques on Information Retrieval of Web Content." IJARCCE 5, no. 8 (August 30, 2016): 347–52. http://dx.doi.org/10.17148/ijarcce.2016.5869.

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"PDC-bit performance under simulated borehole conditions." International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts 31, no. 2 (April 1994): A93. http://dx.doi.org/10.1016/0148-9062(94)93069-4.

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"Proper nozzle location, bit profile, and cutter arrangement affect PDC-bit performance significantly." International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts 32, no. 2 (February 1995): A82. http://dx.doi.org/10.1016/0148-9062(95)94719-1.

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"Optimizing Drill Bits Performance in Highly Unconfined Compressive Strength Formation, Sinai Oil Field, Egypt." International Journal of Recent Technology and Engineering 8, no. 6 (March 30, 2020): 2057–60. http://dx.doi.org/10.35940/ijrte.f7427.038620.

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Abstract:

In Belayim Oil field, Sidri concession, 8 1/2" section is composed of conglomerates with overall Unconfined Compressive Strength (UCS) varies from 25,000 to 40,000 psi. This section was mainly drilled with Polycrystalline Diamond Compact (PDC) bits and Tungsten Carbide Insert (TCI) drill bits. Drilling 1000 meter in 8 1/2" section needed minimum 6 to 8 drill bits. The average rate of penetration (ROP) was 2.8 (meter per hour) MPH and the average drilled interval was 135 m. The rock bit that had been used in offset wells achieved low ROP and short drilled intervals as well, meanwhile, PDC bit achieved moderate average ROP and relatively short run intervals The operator target was to reduce the drilling time by raising ROP and the drilled interval per drill bit; the hybrid bit was presented to achieve that target. The hybrid bit achieved the highest ROP record and the longest drilled interval in Sidri concession achieving 200 percent improvement from offsets’ average performance. Finally, the paper recommended using three hybrid bit in the first three runs and in the fourth run, where the unconfined compressive strength reached its maximum values, TCI drill bit could be used.

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Journal articles on the topic 'PDC bit performance'

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