Academic literature on the topic 'CT Operations'

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Journal articles on the topic "CT Operations"

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Zengmin, Tian, Liu Zonghui, Huang Caibao, and Li Shiyue. "1500 CT-guided stereotactic operations." Clinical Neurology and Neurosurgery 99 (July 1997): S162. http://dx.doi.org/10.1016/s0303-8467(97)82015-x.

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Wieder, H., J. Czernin, B. N. Navar, O. Israel, T. Beyer, and L. S. Freudenberg. "Variations of clinical SPECT/CT operations." Nuklearmedizin 51, no. 04 (2012): 154–60. http://dx.doi.org/10.3413/nukmed-0467-12-01.

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SummaryAim: This survey gathers information about clinical SPECT/CT operations worldwide to help guide standardization of clinical SPECT/ CT imaging. Methods: An international, webbased survey of SPECT/CT users was initiated in 12/2010 through an e-mail distribution. Users were asked 71 questions related to (A) demographics, (B) SPECT/CT operations/utilization and (C) variations in imaging protocols. Results: Collected responses originated from 117 imaging centers in the Americas (66%), Europe (20%), Asia-Pacific (11%) and the Middle-East (3%), with the majority of responding sites representing public health care institutions (69%). Most sites operate 1–2 SPECT/CT-systems (74%), typically installed in Nuclear Medicine departments (84%) with extensive prior SPECT-only experience (82%). Only 14% of SPECT/CTs are installed in Radiology departments. Clinical SPECT/CT imaging is performed either as routine (51%) or ad-hoc “add-on” procedure (49%) with a high inter-site and inter-examination variability. The main application of the integrated CT is to provide anatomical localization of the tracer uptake rather than to produce contrast enhanced or other high-quality CT images. Consequently, in only 22% of the sites a CT contrast injector is installed. Only 6% of centers use SPECT/CT devices for stand-alone CT procedures. Conclusion: An international survey among clinical SPECT/CT users revealed that SPECT/CT is a not a routine component of nuclear medicine procedures. The majority of the centers responding do not fully utilize the diagnostic potential of the CT components. Significant variations in standard imaging protocols were observed. These findings illustrate the need for training and standardization and underscore the need for revisiting the role of SPECT/CT in diagnostic imaging.
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Livescu, Silviu, Steven Craig, and Bill Aitken. "Fluid-Hammer Effects on Coiled-Tubing Friction in Extended-Reach Wells." SPE Journal 22, no. 01 (June 28, 2016): 365–73. http://dx.doi.org/10.2118/179100-pa.

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Summary The lateral reach and residual bottomhole-assembly (BHA) loads in extended-reach wells strongly depend on the coiled-tubing (CT) mechanical friction. Detailed CT-friction modeling becomes crucial in the prejob planning stage to ensure successful job predictability. However, current numerical simulators consider constant coefficients of friction (CoFs) that are determined from similar operations without taking into account the effects of the operational and downhole parameters on the CoF for a specific operation. This study outlines the modeling of CT-friction force, CoF, and axial BHA loads depending on the operational and downhole parameters when a fluid-hammer tool is used. Recent theoretical, laboratory, and field data have established how CoF depends on the downhole parameters (Livescu and Wang 2014; Livescu and Watkins 2014; Livescu et al. 2014a, b; Livescu and Craig 2015). Previously, these effects were not considered in the CT numerical models, leading to significant CoF differences among available commercial simulators. For instance, the default CoFs in the current prejob simulations for cased holes, when no lubricant or friction-reducing tools such as fluid-hammer tools and tractors are used, vary between 0.24 and 0.30 or even higher. This makes it extremely difficult to consistently evaluate and compare the friction-reduction effects of lubricants, fluid-hammer tools, and tractors in extended-reach wells, especially when the field operator may be consulting with several service companies that use different commercial force-modeling software. This study presents the CT-force matching and fundamental physics on the basis of modeled fluid forces, including radial forces, drag forces, and, most importantly, pressure forces on the CT-friction forces caused by fluid-hammer tools. Extending the method of characteristics, regularly used for studying pressure pulses in straight pipes, the perturbations method also accounts for the helical shape of the CT. The new CT fluid-hammer model is validated against laboratory data. This rigorous method for calculating the axial BHA load and reduced CT-friction force caused by radial vibrations can be easily implemented in currently available tubing-force analysis (TFA) software for CT operations. This novel approach, which uses detailed CT mechanical-friction modeling to take into account parameters such as temperature, internal pressure, pumping rate, and others, improves predictions for CT reach in lateral wells. These findings broaden the current industry understanding of the CT mechanical friction modeling in extended-reach wells, and show benefits for the industry when considering variable friction modeling in commercial CT simulators.
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Feder, Judy. "Best Practices for Avoiding Erosion in Annular Fracturing." Journal of Petroleum Technology 73, no. 06 (June 1, 2021): 46–47. http://dx.doi.org/10.2118/0621-0046-jpt.

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This article, written by JPT Technology Editor Judy Feder, contains highlights of paper SPE 204417, “Avoiding Erosion: Best Practices for Coiled Tubing Annular Fracturing Operations,” by Kaveh Yekta, SPE, and Jamie Fenwick, SPE, Essential Energy Services, and Kevin Elliott, SPE, NOV, et al., prepared for the 2021 SPE/ICoTA Virtual Well Intervention Conference, 22–25 March. The paper has not been peer reviewed. The onset of erosion of coiled tubing (CT) strings may be difficult to predict in annular fracturing operations. The complete paper describes a methodology of verifying that CT strings have not been subject to erosion caused by annular fracturing operations. An exploration of pumping rates used on these strings in operations also provides field-tested practical guidelines for avoiding erosion when performing annular fracturing jobs. Inspection A CT string may be exposed to erosion in the outer surface during CT annular fracturing operations. The critical parameters that may influence the magnitude of erosion include fracturing pump rate, sand concentration, fluid rheology, wellbore geometry, and the grade of CT string. One measurable parameter to examine the string’s suitability is the wall thickness for each section. The CT strings discussed in the complete paper were sent for inspection to learn about the effect of the fracturing treatment. A series of nondestructive tests was conducted pre- and post-operation to evaluate the readiness of strings for subsequent operations. The complete paper includes two graphs related to the results of these tests. Materials The API 5ST specification requires using eddy current (EC) inspection for CT. With respect to API 5ST, quenched and tempered tubing had not been addressed at the time of this paper’s submission, so it is not clear whether the CT manufacturers employ EC techniques after quenching and tempering. However, it is expected that all tubing will be subject to EC inspection at least before any quenching and tempering operations. Inspection methodology and equipment consistency is important to establish a baseline inspection necessary for subsequent comparisons. In the case of the CT strings used in this study, all were subject to EC inspection at tubing manufacturing and then subsequently inspected by an outside, third-party vendor using magnetic flux leakage (MFL) technology when spooling the strings on the unit. No known third-party EC vendors can inspect string lengths of CT, so MFL inspection is the only available solution. Photographs of CT inspections taken at the manufacturing facility and the service and distribution point are included in the paper. Several commercial third-party inspection companies operate in North America, where this work was performed. Provided that the inspection can begin by identifying features in the calibration standard (often a through-drilled hole), the selection of inspection methodology is primarily a matter of preference for the service company and operator.
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Geterud, K., Ch Henriksson, S. Pettersson, and B. F. Zachrisson. "Computed Tomography after Percutaneous Renal Stone Extraction." Acta Radiologica 28, no. 1 (January 1987): 55–58. http://dx.doi.org/10.1177/028418518702800111.

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Eighty patients were examined with computed tomography (CT) of the kidney and the retroperitoneal space after percutaneous stone extraction. Most examinations were done within a week after the operation. The morphologic changes were usually small or none. In 7 patients minor renal or perirenal fluid collections were found. Their operations had been complicated by bleeding or leakage. In 66 patients CT was compared with conventional radiographs. Residual stones were more often detected by CT. They were usually small. Percutaneous renal stone extraction is considered a safe and efficient method.
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Zhu, Jun, Feng Tang, and Ye Gu. "A prospective study on the diagnosis of peripheral lung cancer using endobronchial ultrasonography with a guide sheath and computed tomography-guided transthoracic needle aspiration." Therapeutic Advances in Medical Oncology 10 (January 1, 2018): 175883401775226. http://dx.doi.org/10.1177/1758834017752269.

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Background: It is difficult to collect peripheral lung cancer samples. This study analyzed the applicability of endobronchial ultrasonography with a guide sheath (EBUS-GS) and computed tomography-guided transthoracic needle aspiration (CT-TTNA) for the diagnosis of peripheral lung cancer. Methods: A prospective analysis of peripheral lung cancer patients was performed. The study included 150 cases in the EBUS-GS group and 177 cases in the CT-TTNA group. The diagnostic rate, pathological type, genetic status and complications were analyzed. Results: The diagnosis rates were 64.0% and 97.7% in the EBUS-GS and CT-TTNA groups, respectively. The EBUS-GS group had undergone the most operations of the upper lobes of both lungs, while there was no significant difference in the operation distribution among the lobes in the CT-TTNA group. Adenocarcinoma (64 cases versus 51 cases) was most commonly observed in both groups, followed by squamous cell carcinoma. The detection rates of patients who were given a genetic test were 96.1% and 98.9% in the EBUS-GS and CT-TTNA groups, respectively. The incidence of complications in the EBUS-GS group was significantly less than that in the CT-TTNA group. Conclusions: EBUS-GS and CT-TTNA both had operational limitations. The diagnostic rate of EBUS-GS was lower than that of CT-TTNA, but there were fewer complications. CT-TTNA had better tolerance. According to the specific location of the lesion, we recommend EBUS-GS for lesions with a diameter ⩽30 mm and CT-TTNA for lesions with a diameter >30 mm. CT-TTNA specimens were advantageous for genetic testing.
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Livescu, Silviu, and Steven Craig. "Increasing Lubricity of Downhole Fluids for Coiled-Tubing Operations." SPE Journal 20, no. 02 (July 23, 2014): 396–404. http://dx.doi.org/10.2118/168298-pa.

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Summary The requirement for intervention operations in long-reach lateral wells continues to grow. In the US, it is not uncommon to be asked to run coiled tubing (CT) in 10,000-ft laterals. In general terms, a 2-in. CT typically has enough weight reserves to perform work to approximately half such a lateral. Even though increasing the CT diameter remains a theoretical option to improve reach, practically, it creates logistical challenges with both road transport and offshore crane-lifting/deck-loading limitations. Although fluid-hammer tools and downhole tractors have extended the reasonable operational range of CT significantly, they also increase circulating pressures and operational complexity. To reach a 10,000-ft lateral, the use of metal-on-metal lubricants will be required to work in conjunction with the other systems. Obviously, the use of lubricants is not new. Typical real-life results of current systems are approximately a 15 to 20% reduction in the coefficient of friction (CoF) from a generic 0.24 to 0.19. Occasionally, one could obtain smaller CoF values in the field. However, these actual results compare poorly to laboratory testing with a high-pressure rotational friction test. An extensive set of laboratory measurements was carried out with a linear-friction measuring device to understand and quantify the mechanical, chemical, and thermal metal-on-metal wet frictional effects. Particular attention was paid to the synergy between lubricants and the other commonly circulated brines and fluid friction reducers. Other tests, such as regained-permeability and aging tests were also performed. Arising from the trials is a new lubricant that reduced the linear CoF by approximately 40 to 60% (0.10 to 0.12) under downhole conditions. Friction reduction of this magnitude is expected to make it feasible to run CT in 10,000-ft laterals without the use of fluid-hammer tools or tractors. The paper details the new testing method, technical background of frictional drag, existing lubricant case histories, the new laboratory data, details of compatibility tests, and two new-lubricant case histories.
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Carpenter, Chris. "Design and Safety Considerations for Coiled Tubing Operations in Geothermal Wells." Journal of Petroleum Technology 73, no. 07 (July 1, 2021): 51–52. http://dx.doi.org/10.2118/0721-0051-jpt.

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This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper OTC 30408, “Design and Safety Considerations To Perform Coiled Tubing Operations in Large-Diameter, High-Temperature Geothermal Wells,” by Ishaan Singh, SPE, Danny Aryo Wijoseno, SPE, and Kellen Wolf, Schlumberger, et al., prepared for the 2020 Offshore Technology Conference Asia, originally scheduled to be held in Kuala Lumpur, 17–19 August. The paper has not been peer reviewed. Copyright 2020 Offshore Technology Conference. Reproduced by permission. The productive section in a high-pressure, high-temperature (HP/HT) geothermal Field A in the Philippines features shallow and deep reservoirs separated by a low-permeability formation. However, recent years have seen a reduction in production levels. To activate and enhance well production, coiled tubing (CT) nitrogen-lift operations were required. CT simulations were combined with simulations from the geothermal reservoir to overcome modeling limitations. The outcome helped the design of a new cooling-loop system and allowed optimization of the nitrogen-lift technique. As a result, two large-diameter geothermal wells were lifted safely with 2-in. CT. Introduction This study describes design and safety considerations in performing CT operations in high-temperature, large- diameter geothermal wells. The customized high-temperature-grade seal material was chosen to withstand high bottomhole temperatures (BHT) (600°F), and a heat exchanger riser system was designed and tested on the job to handle high-surface-temperature steam (350–400°F), thus mitigating potential well-control incidents. Challenges of Seal Damage Caused by High Surface Temperatures in Live Well Intervention The CT interventions in quenched HP/HT geothermal wells reduce the risk of surface equipment failure. The seal material readily available in the market is rated to 250°F, but, if quenching is not possible, the high-temperature steam (approximately 350–400°F) may flow into the pressure-control equipment, leading to seal damage and CT contingencies. At high temperatures (400°F), these seals are unusable. It becomes essential to use a surface heat exchange riser (HER) system to prevent this issue. Design and Execution of HER Systems in Field A To avoid any well contingency and to keep pressure-control equipment safe, HER systems can be used. Some basic designs for HERs are described in the complete paper. For this study, a customized 4.06-in. HER cooling system (Design 1, shown in Fig. 1) was designed to accommodate 2-in. CT pipe. Design 1 was chosen from an evaluation of three design candidates outlined in the complete paper. The wellhead stack featured seal elements rated to high temperatures (400°F). To prevent high- temperature steam from entering the wellhead stack, the blowout preventer, and other surface- equipment elements, an efficient HER system was designed wherein, while the CT is still in the well performing CT operations, the cold water can be pumped into the CT-stack annulus from the top flow cross through the cooling riser to the bottom flow cross and back to the return tank. The temperature of the cooling loop was continuously monitored to ensure that it was well below 212°F (the boiling point of water).
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Rae, Shivani, Samuel Hall, Owen Sparrow, Nijaguna Mathad, Ryan Waters, and Aabir Chakraborty. "Time-Critical Transfers for Paediatric Neurosurgical Emergencies Operated on Out-of-Hours at a Tertiary Neurosurgical Centre: A Single Centre Experience." Neurosurgery 84, no. 5 (March 23, 2019): E272. http://dx.doi.org/10.1093/neuros/nyz001.p1.

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Abstract INTRODUCTION Recommendations suggest operating within 4 hr of acute brain injury. Centralization of paediatric neurosurgical and intensive care facilities therefore necessitates prompt assessment and transfer. METHODS A retrospective audit of out-of-hours operations at a tertiary neurosurgical center over 2013 to 2016 identified 36 patients (mean age 8 yr (SD = 5); male n = 21) from consultant records and case notes. Initial GCS, transfer timings and 3-mo Glasgow Outcome Score (GOS) were recorded. RESULTS A total of 36 emergency surgeries were performed: hematoma evacuation (n = 17), CSF diversion (n = 16), posterior fossa tumor debulking (n = 1), depressed skull fracture elevation (n = 1) and decompressive craniectomy (n = 1). Median GCS at presentation was 8.5 (range: 3-15). Twenty operations began within 4 hr of CT. Twenty-nine patients presented to district general hospitals, underwent imaging before transfer; their mean CT to arrival time was 197.8 (SD = 70.7) min and CT to operation time was 271.7 (SD = 123.1) min. Three-mo outcomes were: GOS 5 (n = 24), 4 (n = 5), 3 (n = 2) and 1 (n = 5); these were dichotomized into favorable (GOS 4–5) or unfavorable (GOS 1–3). Fisher's exact tests found no significant association between outcome favorability and timing of operation (whether within 4 hr of CT) (P = .43), or operation type (hematoma evacuation vs CSF diversion) (P = .22). Initial GCS did not significantly correlate with GOS (rs = 0.30, P = .10). CONCLUSION The majority of outcomes were favorable regardless of whether surgery occurred within 4 hr of CT. This suggests underlying pathology may have a greater impact on poor outcomes than the transfer time, highlighting the importance of early scanning and neurosurgical referral to facilitate prompt decision-making.
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Beyer, T., J. Czernin, and L. S. Freudenberg. "Variations in Clinical PET/CT Operations: Results of an International Survey of Active PET/CT Users." Journal of Nuclear Medicine 52, no. 2 (January 13, 2011): 303–10. http://dx.doi.org/10.2967/jnumed.110.079624.

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Dissertations / Theses on the topic "CT Operations"

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Ayub, Yasir, and Usman Faruki. "Container Terminal Operations Modeling through Multi agent based Simulation." Thesis, Blekinge Tekniska Högskola, Sektionen för datavetenskap och kommunikation, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-5549.

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This thesis aims to propose a multi-agent based hierarchical model for the operations of container terminals. We have divided our model into four key agents that are involved in each sub processes. The proposed agent allocation policies are recommended for different situations that may occur at a container terminal. A software prototype is developed which implements the hierarchical model. This web based application is used in order to simulate the various processes involved in the following operations on the marine side in a case study of a container terminal in Sweden by adopting a multi-agent based simulation technique. Due to the increase in usage of container transportation, container terminals are experiencing difficulties in the management of the operations. The software provides a decision support capability to terminal managers for scheduling and managing the operations effectively while also visually presenting the time it takes to complete the process and its associated cost. Terminal managers need to implement certain policies to improve the management and operations of the container terminal. The policies are evaluated and tested under various cases to provide a more comparative overview. The results of the simulation experiments indicate that the waiting time for arriving vessels is decreasing when in queue with more than three vessels arriving on same day.
Simulation is a good technique that help analyst to take decision considering each factor of problem that is to be simulated. Simulation in addition with multi agent environment provides better understanding of modeling the entities. The complexity of CT environment and multiple involvement of agents simultaneously enables CT suitable domain for multi agents. We have modeled the four CT operations that are carried out at each CT. These operations are modeled in hierarchical sequence like berth allocation, QCs allocation, Transport vehicles allocation and YCs allocation. The most important factor of simulation is the measurement of dynamic time of each operation. We have simulated and compared different agents active time and service time compared with associated cost. The berth allocation is very important asset from all the operations that are carried out at the CTs. The effective utilization of FCFS berth allocation policy reduces the vessel waiting time in waiting queue. The developed terminal simulator tool allocates all resources dynamically while looking at the number of containers that will be loaded and unloaded at QS and yard storage area. The result of simulation tool presents the good dynamic allocation of transport vehicles. The dynamic resource allocation helps to minimize the congestion and bottlenecks that may occur at CTs. The result of three experiments depicts that the berth allocation and agent allocation is improved and vessel service time is reduced at berth side which automatically reduces vessels waiting time in queue. Besides this the transport allocation and YCs allocation is dynamically assigned by looking at number of containers in the vessels. The terminal simulator helps managers to analyze the simulated results and take better decision at hand.
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Ndegwa, Loise W. "An analysis of the counterterrorism (CT) and counterinsurgency (COIN) operations employed by African Union Mission in Somalia (AMISOM) to counter the threat of al-Shabaab in Somalia (2007- 2016)." Master's thesis, University of Cape Town, 2018. http://hdl.handle.net/11427/29381.

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More than ten years after the deployment of the first African Union Mission in Somalia (AMISOM) troops to Mogadishu, it is imperative that an in-depth analysis is conducted to examine whether the troops have reduced the threat of al-Shabaab in Somalia and the region. This analysis is especially important since AMSIOM is the latest attempt to create a stable and strong central government in Somalia since the fall of Said Barre’s regime in 1991. The extremist group, al-Shabaab, has evolved to become the strongest opponent and obstacle to the creation of the Federal Government of Somalia. The main objective of this dissertation is to challenge the definition of success advocated by AMISOM and its allies regarding their progress in Somalia. This study also aims to analyse the effectiveness of the counterterrorism (CT) and counterinsurgency (COIN) operations employed by AMISOM to reduce the threat of al-Shabaab. To analyse the effectiveness of the CT and COIN operations utilised between 2007 and 2016, this paper will contextualise the body-count approach using data collected from African Union (AU) and United Nations (UN) reports and the Global Terrorism Database (GTD) by the University of Maryland. This study concludes that the weak mandate, which prevented the troops from conducting military offensives, and inadequate troop strength during the first phase of the mission (2007-July 2010), provided al-Shabaab with the right environment to evolve from a terrorist group into an insurgency by securing their support both their domestic and international support. Also, AMISOM’s failure to change their tactics and strategy to account for modifications adapted by al-Shabaab during the second and third phases (July 2010 – May 2012 and June 2012 – December 2016) has contributed to their limited success in Somalia. Although the scope of this study does not discuss all possible reasons for the limited success by AMISOM, it contributes to the larger discussion.
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Brandt, Silvio. "Stellenwert der Spiral-CT und der Sonographie vor und nach Larynx-Operation bei transsexuellen Patientinnen." [S.l.] : [s.n.], 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=970952422.

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池田, 充., Mitsuru Ikeda, 茂樹 伊藤, Shigeki Ito, 武男 石垣, Takeo Ishigaki, Kazunobu Yamauchi, and 一信 山内. "Evaluation of a neural network classifier for pancreatic masses based on CT findings." Elsevier, 1997. http://hdl.handle.net/2237/5311.

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Hossain, Monir. "Fault Discrimination Algorithm for Busbar Differential Protection Relaying Using Partial Operating Current Characteristics." ScholarWorks@UNO, 2016. http://scholarworks.uno.edu/td/2263.

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Differential protection is the unit protection system which is applied to protect a particular unit of power systems. Unit is known as zone in protection terminology which is equivalent to simple electrical node. In recent time, low impedance current differential protection schemes based on percentage restrained characteristics are widely used in power systems to protect busbar systems. The main application issue of these schemes is mis-operation due to current transformer (CT) saturation during close-in external faults. Researchers have suggested various solution of this problem; however, individually they are not sufficient to puzzle out all mis-operational scenarios. This thesis presents a new bus differential algorithm by defining alternative partial operating current characteristics of a differential protection zone and investigating its performance for all practical bus faults. Mathematical model of partial operating current and operating principle of the proposed bus differential relay are described in details. A CT saturation detection algorithm which includes fast and late CT saturation detection techniques is incorporated in relay design to increase the sensitivity of partial operating current based internal-external fault discriminator for high impedance internal faults. Performance of the proposed relay is validated by an extensive test considering all possible fault scenarios.
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Erdmenger, Uwe [Verfasser]. "Bildqualität und Strahlenexposition des Siremobil-IsoC3D : Evaluation der Bildqualität und Strahlenexposition des IsoC3_1hD gegenüber dem 16-Zeilen-Spiral-CT und seiner Einsetzbarkeit bei Operationen am Becken / Uwe Erdmenger." Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2009. http://d-nb.info/1023709724/34.

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Berhouet, Julien. "Optimisation de l'implantation glénoïdienne d'une prothèse d'épaule : de la reconstitution 3D à la réalité augmentée." Thesis, Tours, 2016. http://www.theses.fr/2016TOUR4016/document.

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Deux méthodes d’assistance opératoire, pour le positionnement du composant glénoïdien d’une prothèse d’épaule, sont explorées. Elles ont pour dénominateur commun une reconstruction 3D première de la glène pathologique à implanter. Une approche essentiellement clinique, avec des travaux d’application pratique, est proposée pour la technologie des Patients Specific Implants (PSI), dont l’utilisation en orthopédie est croissante. Une approche davantage technologique est ensuite proposée, de type Réalité Augmentée, jusqu’à maintenant encore inexploitée dans le champ de la chirurgie orthopédique. La faisabilité de cette approche, les conditions d’emploi des technologies inhérentes, ont été étudiées. En amont, un nouveau type d’information pour implémenter, sur le support connecté (lunettes électroniques), l’application de réalité, est proposé, avec la modélisation mathématique par régression linéaire multiple d’une glène normale. L’objectif secondaire est d’obtenir une banque de données dites de glènes génériques normales, pouvant servir de référence à la reconstitution d’une glène pathologique à traiter, après un processus de morphing
In this thesis, two methods of operating assistance for the positioning of the glenoid component of a shoulder prosthesis, are addressed. They have in common a preliminary 3D reconstruction of the pathological glenoid to implant. A main clinical approach, with practice studies, is proposed for the Patient Specific Implants technology, which is currently used in orthopaedics. Then a main prospective and technological approach is proposed with the Augmented Reality, while it is so far untapped in the field of orthopaedic surgery. The feasibility of this last technology, as well as the tools and the manual for its use, were studied. Upstream, a new type of information to implement the augmented reality connected application support is offered, with mathematical modeling by multiple linear regression of a normal glenoid. The second goal is to build a normal generic glenoids database. It can be used as reference to the reconstruction of a pathological glenoid to treat, after a morphing process step
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Tsukayama, John K. "By any means necessary : an interpretive phenomenological analysis study of post 9/11 American abusive violence in Iraq." Thesis, University of St Andrews, 2014. http://hdl.handle.net/10023/4510.

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This study examines the phenomenon of abusive violence (AV) in the context of the American Post-9/11 Counter-terrorism and Counter-insurgency campaigns. Previous research into atrocities by states and their agents has largely come from examinations of totalitarian regimes with well-developed torture and assassination institutions. The mechanisms influencing willingness to do harm have been examined in experimental studies of obedience to authority and the influences of deindividuation, dehumanization, context and system. This study used Interpretive Phenomenological Analysis (IPA) to examine the lived experience of AV reported by fourteen American military and intelligence veterans. Participants were AV observers, objectors, or abusers. Subjects described why AV appeared sensible at the time, how methods of violence were selected, and what sense they made of their experiences after the fact. Accounts revealed the roles that frustration, fear, anger and mission pressure played to prompt acts of AV that ranged from the petty to heinous. Much of the AV was tied to a shift in mission view from macro strategic aims of CT and COIN to individual and small group survival. Routine hazing punishment soldiers received involving forced exercise and stress positions made similar acts inflicted on detainees unrecognizable as abusive. Overt and implied permissiveness from military superiors enabled AV extending to torture, and extra-judicial killings. Attempting to overcome feelings of vulnerability, powerlessness and rage, subjects enacted communal punishment through indiscriminate beatings and shooting. Participants committed AV to amuse themselves and humiliate their enemies; some killed detainees to force confessions from others, conceal misdeeds, and avoid routine paperwork. Participants realized that AV practices were unnecessary, counter-productive, and self-damaging. Several reduced or halted their AV as a result. The lived experience of AV left most respondents feeling guilt, shame, and inadequacy, whether they committed abuse or failed to stop it.
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Lin, Jih-Yang, and 林繼洋. "Simulation of The Operation Support System Software for CT-2 Networking System." Thesis, 1996. http://ndltd.ncl.edu.tw/handle/59149266240843951124.

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Lin, Ji Yang, and 林繼洋. "Simulation of the operation support system software for CT-2 networking system." Thesis, 1996. http://ndltd.ncl.edu.tw/handle/62019854434047369430.

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Books on the topic "CT Operations"

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Dawson, Ed. Topics in Cryptology – CT-RSA 2013: The Cryptographers’ Track at the RSA Conference 2013, San Francisco,CA, USA, February 25-March 1, 2013. Proceedings. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013.

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David, Pointcheval, ed. Topics in cryptology: CT-RSA 2006 : the Cryptographers' Track at the RSA Conference 2006, San Jose, CA, USA, February 13-17, 2006 : proceedings. Berlin: Springer, 2006.

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Attack of the HMS Nimrod : : Wareham and the War of 1812. The History Press, 2014.

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Pointcheval, David. Topics in Cryptology -- CT-Rsa 2006. Springer, 2008.

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Menezes, Alfred John. Topics in Cryptology -- CT-Rsa 2005. Springer, 2008.

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Malajikian, Krikor, and Daniel Finelli. Basics of Computed Tomography. Oxford University Press, 2016. http://dx.doi.org/10.1093/med/9780199908004.003.0003.

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Computed tomography (CT)-guidance is typically used when precise needle placement is essential for a successful procedure. It uses ionizing radiation, which could pose risks to the patient and operating staff if proper technique is not used. The performing physician should adhere to all principles of minimizing radiation exposure to the patient and clinicians. Common CT-guided imaging procedures include facet injections, nerve root injections, sacroiliac joint injections, intradiscal procedures, vertebroplasty/sacroplasty, and image-guided ablation of painful bone lesions. Computed tomography is also the imaging modality of choice for aspiration of deep paraspinal soft tissues in addition to disc space or bone biopsy in acute discitis/osteomyelitis. In fluoroscopic-guided knee or shoulder joint injections, CT arthrography is a useful adjunct to better assess anatomy when MRI is contraindicated. When imaging the postoperative spine, CT myelography has some advantages over MRI, and CT is also superior to MRI in assessing par intra-articularis defects or spondylolysis.
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Brandt, Sebastian, and Hartmut Gehring. Anaesthesia for medical imaging and bronchoscopic procedures. Edited by Peter F. Mahoney and Michel M. R. F. Struys. Oxford University Press, 2017. http://dx.doi.org/10.1093/med/9780199642045.003.0077.

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Anaesthesia in ‘remote areas’ is required for medical imaging (CT, MRI, PET-CT), angiography, endoscopy, and interventions (stenting, thrombectomy, coiling, laser therapy, biopsies, radiotherapy) in a number of medical disciplines (paediatrics, radiology, cardiology, pulmonology, gastroenterology, surgery, cardiac surgery, emergency medicine). The spectrum of anaesthetic techniques is broad. It reaches from standby (monitored anaesthesia care), through analgesia and sedation (with spontaneous breathing), to general anaesthesia and mechanical ventilation. Regional anaesthesia techniques are also required under certain circumstances. In the last few years there has been a move away from open procedures to interventional techniques. The complexity of these interventions has increased (i.e. interventional cardiac valve replacements) and the patients tend to be older and suffer from a multitude of co-morbidities. Many of these interventions are performed in the ‘hostile environment’ of the intervention suite. Intervention suites are typically not designed to offer anaesthetists an ideal working area. The space may be limited and medical equipment impedes access to the patient. The infrastructure may be suboptimal (e.g. no central medical gases supply). Protection for staff and equipment against radiation and high magnetic fields must be considered. Loud noise from machinery and shielded walls, doors, and windows may hinder communication and hearing acoustic alarms. The distance to the operating theatre may be considerable and thus support from senior anaesthetists and supply of additional equipment may take some time to arrive. Anaesthesia outside the operating theatre is sometimes underestimated as trivial. Performing a ‘quick’ interventional case can evolve within seconds into a challenge even for the experienced anaesthesiologist if a surgical or anaesthesiological complication occurs. Non-operating-theatre anaesthesia has a higher severity of injuries and more substandard care than operating theatre anaesthesia. This is not acceptable and anaesthetists must ensure the same high standard of anaesthesia care and patient safety both inside and outside the operating theatre.
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Dodds, Chris, Chandra M. Kumar, and Frédérique Servin. Anaesthesia for non-theatre environments. Oxford University Press, 2017. http://dx.doi.org/10.1093/med/9780198735571.003.0013.

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This chapter reviews the challenges in providing safe anaesthesia outside of the operating theatre complex and the particular risks this may pose to the elderly. Generic issues with remote sites are discussed, and key points are identified: these include patient assessment, appropriate staffing and support, safety drills, environmental safety, and anaesthetic equipment and drug provision. Sedation in the elderly is identified as an area of risk, and the chapter details the problems of providing safe sedation. The areas where sedation is administered vary from endoscopy and imaging including CT and MRI, to interventional suites such those used for cardiothoracic catheterization and GI stenting. Major advances in technology have allowed the development of endovascular aortic aneurysm repair (EVAR) and transthoracic aortic valve implantation (TAVI). Psychiatric units still prescribe electroconvulsive therapy (ECT) for severe suicidal depression, especially in the elderly because of the fast response, and the related challenges for anaesthetists are reviewed.
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Menezes, Alfred John. Topics in Cryptology -- CT-RSA 2005: The Cryptographers' Track at the RSA Conference 2005, San Francisco, CA, USA, February 14-18, 2005, Proceedings (Lecture Notes in Computer Science). Springer, 2005.

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Pointcheval, David. Topics in Cryptology -- CT-RSA 2006: The Cryptographers' Track at the RSA Conference 2006, San Jose, CA, USA, February 13-17, 2005, Proceedings (Lecture Notes in Computer Science). Springer, 2006.

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Book chapters on the topic "CT Operations"

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Winkel, James P., James C. Akers, and Erica Bruno. "Feasibility Study of SDAS Instrumentation’s Ability to Identify Mobile Launcher (ML)/Crawler-Transporter (CT) Modes During Rollout Operations." In Sensors and Instrumentation, Aircraft/Aerospace, Energy Harvesting & Dynamic Environments Testing, Volume 7, 101–21. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-47713-4_12.

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Kachelriess, Marc. "Principles, Design, and Operation of Multi-slice CT." In Clinical PET-CT in Radiology, 1–19. New York, NY: Springer New York, 2010. http://dx.doi.org/10.1007/978-0-387-48902-5_1.

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Townsend, David W. "Design and Operation of Combined PET-CT Scanners." In Clinical PET-CT in Radiology, 29–38. New York, NY: Springer New York, 2010. http://dx.doi.org/10.1007/978-0-387-48902-5_3.

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Mazur, Wojciech, Marilyn J. Siegel, Tomasz Miszalski-Jamka, and Robert Pelberg. "Arterial Switch Operation for Transposition of the Great Arteries." In CT Atlas of Adult Congenital Heart Disease, 283–88. London: Springer London, 2013. http://dx.doi.org/10.1007/978-1-4471-5088-6_24.

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Weller, Gregory E. R. "Anesthesia in the MRI Suite and for CT Scan." In Out of Operating Room Anesthesia, 205–19. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-39150-2_16.

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Vogt, Florian, Sophie Krüger, Timo Zinßer, Tobias Maier, Heinrich Niemann, Werner Hohenberger, and Christoph Schick. "Fusion von Lichtfeldern und CT-Daten für minimal-invasive Operationen*." In Informatik aktuell, 309–13. Berlin, Heidelberg: Springer Berlin Heidelberg, 2004. http://dx.doi.org/10.1007/978-3-642-18536-6_63.

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Miyazawa, T., K. Tsuchiya, T. Kaji, S. Ishihara, H. Nawashiro, H. Takiguchi, A. Shimizu, K. Shima, and H. Chigasaki. "Usefulness and limitations of 3D-CT angiography for operation of meningiomas." In Proceedings of the XV Symposium Neuroradiologicum, 179–80. Berlin, Heidelberg: Springer Berlin Heidelberg, 1995. http://dx.doi.org/10.1007/978-3-642-79434-6_87.

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Yasuda, Takami, Shigeki Yokoi, and Jun-ichiro Toriwaki. "3-D Brain CT Image Display for Planning of Craniofacial Operation." In Science on Form, 289–95. Dordrecht: Springer Netherlands, 1986. http://dx.doi.org/10.1007/978-94-009-3757-4_35.

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Siebel, T., and M. Porsch. "Roboterassistierte CT-gestützte Operation der PFC-Knieendoprothese mit dem CASPAR-Operationsroboter." In Navigation und Robotic in der Gelenk- und Wirbelsäulenchirurgie, 291–94. Berlin, Heidelberg: Springer Berlin Heidelberg, 2003. http://dx.doi.org/10.1007/978-3-642-55784-2_36.

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Wanifuchi, Hiroshi, A. Sasahara, and S. Sato. "CT evaluation of late cerebral infarction after operation for ruptured cerebral aneurysm." In Acta Neurochirurgica Supplement, 229–30. Vienna: Springer Vienna, 2008. http://dx.doi.org/10.1007/978-3-211-75718-5_44.

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Conference papers on the topic "CT Operations"

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Nguyen, Quoc Phuc, Pacelli Lidio Jose Zitha, Peter K. Currie, and William Richard Rossen. "CT Study of Liquid Diversion with Foam." In SPE Production Operations Symposium. Society of Petroleum Engineers, 2005. http://dx.doi.org/10.2118/93949-ms.

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Singh, Ishaan, Akash Ramesh Pathak, Juhi Kaushik, Bholanath Bandyopadhyay, Danny Aryo Wijoseno, Madhurjya Dehingia, Debanuj Khound, Ajit Kumar Medhi, and Pritam Sharma. "Coiled Tubing Dewaxing Operations: Case Studies in Reduced Production Wells of Northeast India." In IADC/SPE Asia Pacific Drilling Technology Conference. SPE, 2021. http://dx.doi.org/10.2118/201017-ms.

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Abstract Executing interventions in wells encrusted with wax is challenging because experience with global coiled tubing (CT) dewaxing operations is limited, and equipment failure and stuck pipe risks are high. With few jobs performed worldwide, CT dewaxing (hot oil circulation with CT) operations are largely unexplored. The deviated wells in a field in northeast India pose several challenges including completely seized wellbore due to paraffin/asphaltene deposition, previous failed well cleanout attempts, very slow and low bottomhole assembly (BHA) penetration, pumping corrosive and flammable low wax crude (LWC) through CT, high chances of CT getting stuck, and pumping heated 69°C LWC through the CT. This case study delivers insights about design, safety, and operational considerations for 1.5-in. CT dewaxing and nitrogen lift operations in a subhydrostatic well in the field. The objective of this CT dewaxing and nitrogen kickoff operation was to clear the well of paraffin/asphaltene/wax to 1600 m and activate it with nitrogen, and this paper describes solutions for cleaning out and nitrogen-lifting wells with declining production due to paraffin and asphaltene deposition. One well is described in this case study, but this approach can be used perform CT intervention in similar wells. For this case, simulations were sensitized to identify the best combination of pumping rates, CT speeds, and fluid temperature to remove deposits hindering BHA penetration. This study proposes prevention measures using appropriate grounding and procedures, which determine if the crude oil can be pumped through CT. By use of this methodology, 581 dewaxing runs have been performed in 78 wells. Extensive on-job experience and lessons learnt by performing this operation over the last 3 years bring excellent results and prevent misruns. In many cases, production has been restored from nil; several examples feature a fivefold improvement of productivity thanks to this intervention method. Optimized operational parameters such as CT speed, pumping rates, and the use of smaller outer diameter BHAs doubled operational efficiency during those operations. In addition, strict application of the recommendations prevented the occurrence of operational problems such as stuck CT, crude oil flashing, sand bridging, and equipment failure.
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Newman, Ken, Patrick Kelleher, and Brian Gunby. "Optimizing CT Material Properties for Extended Reach Operations." In SPE/ICoTA Coiled Tubing and Well Intervention Conference and Exhibition. Society of Petroleum Engineers, 2017. http://dx.doi.org/10.2118/184749-ms.

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Yekta, Kaveh, Jamie Fenwick, Kevin Elliott, and John Albaugh. "Avoiding Erosion: Best Practices for Coiled Tubing Annular Frac Operations." In SPE/ICoTA Well Intervention Conference and Exhibition. SPE, 2021. http://dx.doi.org/10.2118/204417-ms.

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Abstract Annular Frac operations performed with Coiled Tubing (CT) offer many advantages for unconventional completions, particularly wells with long laterals and many pay zones (frequently in excess of 100 stages). The primary disadvantage to annular frac is erosion of the coiled tubing due to impinged, high pressure fluids containing abrasive frac sand. This paper will describe a methodology to detect erosion of the CT to provide consistent, reliable operations. When designing equipment and writing operational procedures to detect erosion in annular frac through coiled tubing, the following considerations may be considered: CT string design and pumped fluid flow rate when fracturing. From a CT service company perspective, the fluid dynamics of the pumped fluid may contain uncontrolled variables such as fluid density, viscosity, and slurry from job-to-job. As a result of the limitations noted above, the onset of erosion may be difficult to predict. However non-destructive electromagnetic inspection can be utilized to highlight possible locations of erosion within CT strings to develop "field-tested" guidelines for pumping against tubing size. Electromagnetic inspection using Magnetic Flux Leakage (MFL) and/or Hall Effect Sensors can highlight localized variations in wall thickness. However, this information alone does not give a clear indication if the tubing has been damaged by erosion without a baseline inspection to compare to, since there can be variations in wall due to the CT manufacturing process and the prevalence of tapered CT string designs. If the CT string is inspected either when new or very early on in its life, a comparison of wall variation by electromagnetic methods can "rule out" wall thickness variations that were present at the time of manufacturing. Evaluation of CT strings with electromagnetic inspections performed when new and after retirement will be presented in this paper. The inspection results will then be supplemented by pumping parameters from annular frac jobs performed with these strings. This paper describes a methodology of verifying that CT strings have not been subject to erosion due to annular frac operations. An exploration of pumping rates used on these strings in operations also provides some "field-tested" practical guidelines for avoiding erosion when performing annular frac jobs.
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Mohamed, Nebras A., Alwaleed Abd-alrahman Basher, and Mawahib GafarAbd-alrahman Ahmed. "Detection of CT-Liver Lesions using Otsu Algorithm and Morphological Operations." In 2019 International Conference on Computer, Control, Electrical, and Electronics Engineering (ICCCEEE). IEEE, 2019. http://dx.doi.org/10.1109/iccceee46830.2019.9071105.

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Fallahi, Ali Reza, Mohammad Pooyan, and Hojat Mohammadnejad. "Application of Morphological Operations in Human Brain CT Image With SVM." In 2009 3rd International Conference on Bioinformatics and Biomedical Engineering (iCBBE). IEEE, 2009. http://dx.doi.org/10.1109/icbbe.2009.5162390.

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Abdo, Jamil, and Hamed Al-Sharji. "Investigation of Inducing Vibration to Reduce Friction of Coiled Tubing in Deep Drilling Operations." In ASME 2014 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/imece2014-40007.

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This work examines the buckling behavior of constrained horizontal tubular in a cylinder subjected to axial compression force. Such configurations are of interest to coiled tubing (CT) and conventional hydrocarbon drilling. When compression force is applied beyond a critical value the coiled tubing (CT) will buckle forming sinusoidal wave and with increasing the load the CT ultimately goes into a helical configuration. The friction is introduced due to the contact between the CT and the borehole wall. Increasing the CT friction eventually leads to lock-up length beyond which the drilling cannot proceed further. Vibration is a well-known technique to reduce friction between contacting bodies in many engineering systems. An in-house experimental setup is developed to imitate the wellbore being drilled with the presence of drilling fluids and vibrating facility that has the capability to vibrate the CT axially. The setup is employed to examine the effects of amplitude and frequency of vibration on the axial force transfer and weight on bit (WOB) at normal and high temperature environments. Results show that both amplitude and frequency have significant effects in reducing the friction and they alter the buckling behavior on both normal and high temperature.
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Conrad, A. Bruce. "A Case Study of Downhole Obstruction Avoidance for CT-Conveyed TCP Operations." In SPE/ICoTA North American Coiled Tubing Roundtable. Society of Petroleum Engineers, 1997. http://dx.doi.org/10.2118/38426-ms.

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Schamp, J. H., and P. V. R. Suryanarayana. "Job Tracking Using Local Friction Profile to Minimize Risk in CT Operations." In SPE/ICoTA Coiled Tubing Roundtable. Society of Petroleum Engineers, 1998. http://dx.doi.org/10.2118/46032-ms.

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Talha, Umar, Tariq Mairaj, Waleed Bin Yousuf, and Omer Zia. "Morphological operations and re-projection based novel low-dose CT reconstruction scheme." In 2017 International Conference on Communication, Computing and Digital Systems (C-CODE). IEEE, 2017. http://dx.doi.org/10.1109/c-code.2017.7918965.

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