bluuebunny/crossref_metadata_2025_split huggingface dataset:
Using Electric-Line Tools To Clean Wellbore Laterals and Perforate Toes
Authors: Gomez L. D. , Miller N. , Binnion K. 
Published: March 2013

Abstract
Coiled tubing (CT) is invaluable equipment in shale oil/gas completion operations. From well cleanout to perforating and fracturing operations, CT does it all. However, with the boom in shale oil/gas development and the number of wells required to develop these unconventional resources, demand and cost for CT can be high and often availability can be limited.
In an effort to reduce completion costs and minimize CT use, reserving it for only those tasks that absolutely require it, an operator in the Eagle Ford shale decided to investigate alternative technologies for performing post-cementing well cleanup and toe perforating. The operator was aware of an electric-line (e-line), tractor-conveyed cleaning tool with a reverse circulating bit (RCB) that was being used for drifting and cleanout runs. These tools have been used successfully in Norway and Canada, offshore and on land, to clean out cement stringers and other debris from the wellbore, ensuring a clear path for the toe perforations, which follow. With these tasks successfully completed, the pumping down of frac plugs can be accomplished with confidence during multi-stage completion operations.
The operator decided to try the e-line technology on a five-well pilot project of cased, horizontal wells in the Eagle Ford development. This was the first time the technology was used in U.S. land operations. The e-line cleaning tool cleaned the wells, and the tractor-conveyed perforating guns reached the depth cleaned out by the e-line cleaning tool. On this pilot project, the average field time per well for an e-line cleanout and tractor-conveyed toe perforation was 24 hours. The pilot test was considered a success.
This paper discusses the details of the project and tool operations for each well, and the lessons learned and applied to each successive well in the pilot to develop a successful strategy for using these tools across a broad range of operating conditions.
Feasibility Study of Underbalanced Drilling Using Coiled Tubing (CT-UBD) : A Case Study Field "A", Indonesia
Authors: Marbun B. T. , Arliyando L. , Sinaga S. Z. , Arimbawa G. V. 
Published: March 2013

Abstract
Field "A" in Indonesia will be drilled dual lateral using underbalanced drilling technique. The reservoir has been highly depleted, low reservoir pressure about 1130 psi and high bottom hole temperature about 350°F. This field produce natural gas and condensate which contain 80-100 ppm H2S, 15% CO2 and water. Underbalanced drilling will be conducted to minimize the potential problems by utilize Coiled Tubing and nitirified mud.
Coiled Tubing Drilling (CTD) has reached its popularity in last two decades. In principle, CTD provides hydraulic horsepower which is transfered to the bottomhole. In operation, CT has advantages and disadvantages compared to jointed pipe. CT Unit (CTU) are complete package consists of surface and subsurface equipments.
Underbalanced drilling has several advantages: to minimize problems, such as lost circulation, pipe sticking, formation damage, etc. From several drilling fluid, only two types are available in this field and nitrified mud is choosen for several reasons and based on qualitative method regarding factors: wellbore diameter, water influx, gas production, and Extended Reach Drilling (ERD). Gas injection methods are also reviewed.
Combination of CTD and underbalanced drilling, which is dual lateral drilling, delivers maximum productivity improvement compared to single lateral. This is obtained from well performance study or upflow performance study from existing wells. This study is conducted to estimate productivity improvement for various lateral configurations, liner diameter, and well position.
This paper discusses the multiphase flow modelling of underbalanced drilling in Field "A" to determine operational drilling parameters, to select effective drilling fluid and to select CT string and BHA. The main concerns are the challenging conditions in Field "A": 1). High temperature, 2). Corrosive environtment, and 3) Requirement of effective drilling fluid. The outcome of this paper is to provide analysis of upflow performance study, operational window parameters, optimal drilling fluid, and CT string and BHA.
To Mill or Not to Mill: A Fully Retrievable Multistage Fracturing System
Authors: Griffin John , Barraez Rair , Campbell Sean 
Published: March 2013

Abstract
With the increase in horizontal wellbore lengths, effective hole cleaning and efficient milling practices play a critical role in coiled tubing (CT) extended reach applications. Multistage hydraulic fracturing of unconventional reservoir plays has focused horizontal completion techniques on one of two primary types: plug-and-perf or ball-and-seat liner systems. The introduction of ball-and-seat technology in the middle of the last decade was a breakthrough in the horizontal stimulation completion process and significantly impacted the ability of operators to economically develop shale and tight oil reservoirs.
Most current completion systems require post-fracturing milling interventions to restore full wellbore access and remove flow restrictions. To address the challenges associated with plug milling or opening ball seats up to the full liner drift diameter, fully retrievable single-trip systems have been developed. These next generation systems require no post-stimulation milling or drilling while maintaining the benefits of both the plug-and-perf and the ball-and-sleeve completion methods through the use of retrievable isolation plugs and ball seats. Workover time can be decreased over 40%, eliminating costly milling operations. The uncertainty in both milling efficiency and the removal of debris is replaced with a simple set-down and release mechanism which leaves the wellbore unobstructed for any future well interventions. The retrievable seat system has the added advantage of leaving behind a shiftable sleeve which can be activated numerous times.
Over 600 stages of the retrievable seat system have been successfully installed and retrieved within the last 12 months while providing operators the future ability to shut off zones which may unfavorably affect production by water or gas break through. This paper will address sleeve and plug retrieval versus milling, comparing job times, cost, operating efficiencies and equipment requirements.
A Chronological Review of Concentric Coiled Tubing Vacuum Technology: Past, Present and Future
Authors: Pineda Rodolfo , Lindsey B. J. , Taggart Michael , Smith Simon , Ababou Mounir 
Published: March 2013

Abstract
Concentric Coiled Tubing Vacuum Technology (CCTVT) was developed in the mid 1990s in Canada, and since then has spread worldwide. The technology was initially focused on sand cleanouts in heavy-oil, low-pressure, deviated wells, where other cleanout methods, including conventional CT interventions, were inefficient. Under such conditions, CCTVT provided a simple but very effective solution.
In general terms, the technology comprises a downhole jet pump run on a concentric coiled tubing (CCT), which is a coiled tubing string inside another coiled tubing string. A single-phase fluid is pumped through the inner string to power the downhole jet pump, creating a localized drawdown that vacuums well fill (fluids and/or solids), increases the return pressure, and circulates fluids and solids back to surface via the CCT annulus.
Since the introduction of this technology, it has gone through several updates in order to face new challenges. The latest BHA versions include multiple operational modes to improve cleanout efficiency, minimize runs, function with supplementary tools and most recently, to accommodate a specialized electric conductor to run a real-time logging tool in conjunction with the jet pump.
Currently, the application of the system has extended beyond solids removal on heavy oil, onshore wells. The current work scope ranges from very simple operations such as drilling fluid and filter cake removal, liquid unloading, inflow profiling, evaluating completion integrity, matrix stimulation, pressure and temperature logging, etc.; to more complex and challenging operations such as memory production logging, H2S inhibition, multilateral wells, chemical sand consolidation, hydrate removal and realtime production logging. These operations are occurring in the full range of oilfield locations: onshore and offshore wells, from fixed installations to mobile rigs, in jungle to arctic conditions.
This paper will summarize the new techniques that are being applied in many global locations with CCTVT. Each technique will be illustrated with case histories detailing time and cost savings and, where relevant, production improvements.
New Coiled Tubing Pipe Failure Mechanism Identified in Severe Dynamic Conditions - The Potential Effects of Running Speed on pipe Performance
Authors: Cano Valeriano , Reichert Bruce , Grimaldo Carmen , Addison Ryan 
Published: March 2013

Abstract
The use of large-diameter coiled tubing (CT) pipe, 2 inches and greater, as the typical work strings in HP/HT extended reach wells has brought new challenges to the CT intervention industry. The CT strings utilized in this service are expensive and, by nature, short-lived expendables. As well reach increases, the strings become increasingly more sophisticated and costly. Identifying, predicting and controlling the factors that govern the pipe reliability is important to further extend the usable life of strings and contribute to the operational and economical success of CT service providers, CT pipe manufacturers and O&G operators.
Furthermore, if any CT failure takes place, the root cause investigation is essential to the continuous improvement of the service and must be looked at in a holistic, systematic manner [1][2][6]. Hence we must understand how the combination of operational procedures, surface equipment, CT pipe manufacturing, and overall well conditions can affect pipe performance.
In this proactive process, a new mechanism that can contribute to failures has been identified. This failure mode is associated with larger outside diameter (OD) CT pipe being subjected to a combination of high hoop stresses, high strain levels and run-in or retrieved from wells at high speeds. These new set of operational dynamic conditions expose the CT pipe material to higher forces, stresses and deformations not considered in the traditional conventional working envelope and in the associated performance tests and models.
This new field CT pipe failure mechanism is presented in this work, its possible origins are explained in addition to laboratory test data reproducing such failures and identifying the potential set of combined operational conditions in which it can take place.
An alternative CT fatigue-data generation procedure is proposed to better predict pipe performance, avoiding failures under field conditions, improve operational procedures, and enhance overall service quality.
State-of-the-Art Portable Measurement and Defect Detection Technology for Coiled Tubing String
Authors: Zheng Andrew , Liu Zhanke , Zwanenburg Mirjam , Burgos Rex , Stayer Aaron 
Published: March 2013

Abstract
Most coiled tubing (CT) string failures in the field can be traced back to some initial defects, such as mechanical damage, a corrosion pit, a manufacturing defect, etc. Because of the ductility of CT, the introduction of these initial defects doesn’t normally cause failure at the onset. However, over the course of the service life, these initial defects evolve or grow until they reach a critical stage, leading to eventual failure. To assess the serviceability of a CT string, the industry has largely relied on periodic pipe inspection using magnetic flux leakage (MFL). Since MFL signals arise from a complex combination of defect geometry, defect severity, and material anomaly, etc. in the pipe wall, they are very difficult to interpret. A "snapshot" inspection of the string may not provide adequate information to fully evaluate its integrity and/or future serviceability.
To improve assessment of CT string serviceability, a new approach has been developed. The "continuous" inspection approach involves MFL monitoring of the CT string during utilization. With the continuous MFL monitoring from "new" pipe state through its entire service life, the MFL signal directly attributed to defects can be isolated and tracked, leading to an improved evaluation of the CT string’s condition and future serviceability. In conjunction with the theoretical fatigue life tracking, a new pipe Degradation Parameter is used to improve the management of aging coiled tubing.
The state-of-the-art portable measurement and defect detection technology for CT strings uses MFL to detect the existence of defects and to measure wall thickness. It uses eddy current technology to measure the outside diameter (OD) of the pipe. MFL measurements are used to evaluate the defects over successive operations. Wall thickness and OD measurements are used in a real-time software to update the CT working envelope and the fatigue life. By integrating these features into a small portable device suitable for real-time inspection, this technology significantly improves the ability to monitor overall pipe integrity.
Does a Lack of Choice Lead to Lower Quality? Evidence from Auditor Competition and Client Restatements
Authors: Newton Nathan J. , Wang Dechun , Wilkins Michael S. 
Published: March 2013

SUMMARY:
We examine the relationship between auditor competition and the likelihood of financial restatements that occur as a result of failures in the application of generally accepted accounting principles (GAAP). Policy makers and audit market participants have expressed concern that the current level of auditor competition is low, resulting in a negative impact on audit quality. However, we find that restatements are more likely to occur in metropolitan statistical areas (MSAs) that have higher auditor competition. The association between audit market competition and restatements is statistically and economically significant. Our finding of a positive relationship between the likelihood of restatement and audit market competition is relevant to the ongoing debate regarding audit quality and the concentration of audit markets.
Accounting for the Public Interest: A Revenue Recognition Dilemma
Authors: Savage Arline , Cerf Douglas C. , Barra Roberta A. 
Published: March 2013

ABSTRACT:
This case illustrates how accounting rules impact the public interest and vice versa. The setting is a gray area of accounting in which management, the external auditors, the SEC, and international accounting standard setters may have differing opinions about the accounting treatment. Students consider the situation in which an accounting rule leads to a business and societal problem. They gain an understanding of how this happens and how such problems can be addressed. The context for this case is a revenue recognition issue for bill-and-hold sales. It also provides students with the opportunity to consider the real-world implications of accrual- versus cash-based accounting. This case is useful for intermediate- to graduate-level financial accounting classes or an accounting capstone class.
Dream Chocolate Company: Choosing a Costing System
Authors: Krumwiede Kip R. , Walden W. Darrell 
Published: March 2013

ABSTRACT:
This case is about a small, but real, company, Dream Chocolate (D.C.), which makes custom-labeled, high-quality candy bars for special events and advertising purposes. Like many small companies, D.C. has an inadequate costing system and needs a much better one as it starts to get bigger orders. In Part A of this case, students learn how to analyze a company's situation, identify relevant information in a case that is presented in a less-structured format, evaluate the pros and cons of different costing approaches, recommend an approach, and suggest ways to implement it. In Part B, they develop and calculate costs based on their recommended approach. The case also helps increase students' understanding of the applicability of various costing methods typically covered in cost and managerial accounting courses.
DISCUSSION OF: Divestitures of Equity by Executives and Future Equity Granting Patterns
Authors: Black Dirk E. , Dikolli Shane S. 
Published: March 2013

ABSTRACT
Cadman (2013) finds empirically that in response to a CEO divestiture of ownership, boards impose higher compensation risk on CEOs via a higher magnitude of equity grants that are also a higher proportion of annual compensation. The intuition is that by divesting, the CEO diversifies personal wealth risk, which enables boards to impose more risk via variable compensation, over and above what conventional economic determinants would predict. The study highlights the difficulties associated with connecting conventional agency theory to standard empirical tests of the economic determinants of compensation and the importance of measurement in understanding personal wealth diversification. The study also has implications for tests of cross-sectional differences in the pay-for-performance relation associated with CEO divestitures.
Bracket base remnants after orthodontic debonding
Authors: Zanarini Matteo , Gracco Antonio , Lattuca Monica , Marchionni Silvia , Gatto Maria Rosaria , Bonetti Giulio Alessandri 
Published: March 2013

ABSTRACT

Objective:
To evaluate whether the debonding procedure leads to restitutio ad integrum of the enamel surface by investigating the presence of enamel within the bracket base remnants after debonding.

Materials and Methods:
Sixty patients who completed orthodontic treatment with fixed appliances were included. A total of 1068 brackets were microphotographed; the brackets presenting some remnants on the base (n  =  818) were selected and analyzed with ImageJ software to measure the remnant area. From this population a statistically significant sample (n  =  100) was observed under a scanning electron microscope to check for the presence of enamel within the remnants. Energy dispersive x-ray spectrometry was also performed to obtain quantitative data.

Results:
Statistically significant differences in the remnant percentage between arches were observed for incisor and canine brackets (P &lt; .0001 and P  =  .022, respectively). From a morphologic analysis of the scanning electron micrographs the bracket bases were categorized in 3 groups: group A, bases presenting a thin enamel coat (83%); group B, bases showing sizable enamel fragments (7%); group C, bases with no morphologic evidence of enamel presence (10%). Calcium presence was noted on all evaluated brackets under energy dispersive x-ray spectrometry. No significant difference was observed in the Ca/Si ratio between group A (16.21%) and group B (18.77%), whereas the Ca/Si ratio in group C (5.40%) was significantly lower than that of the other groups (P &lt; .323 and P  =  .0001, respectively).

Conclusion:
The objective of an atraumatic debonding is not achieved yet; in some cases the damage could be clinically relevant.
Comparison of overground and treadmill-based gaits of dogs
Authors: Torres Bryan T. , Moëns Noel M. M. , Al-Nadaf Sami , Reynolds Lisa R. , Fu Yang-Chieh , Budsberg Steven C. 
Published: March 2013

Abstract
Objective—To compare overground and treadmill-based gaits of dogs.
Animals —5 clinically normal adult mixed-breed dogs.
Procedures—To obtain dynamic gait data, 30 retroreflective markers were affixed bilaterally to specific regions of the hind limbs and pelvis of each dog. For each dog, 3-D joint motion data (sagittal [flexion and extension], transverse [internal and external rotation], and frontal [abduction and adduction] planes of motion) for the hip, femorotibial, and tarsal joints were acquired during walking and trotting through a calibrated testing space overground or on a treadmill. Comparison of data was performed via generalized indicator function analysis and Fourier analysis.
Results—Both overground and treadmill-based gaits produced similar waveforms in all planes of motion. Fourier analysis revealed no difference between overground and treadmill-based gaits in the sagittal plane of motion; however, small differences were detected between overground and treadmill-based gaits in the other 2 planes of motion. Additionally, femorotibial joint motion during walking did not differ among planes of motion. Generalized indicator function analysis was able to detect differences between overground and treadmill-based gait waveforms in all planes of motion for all joints during walking and trotting.
Conclusions and Clinical Relevance—In dogs, overground and treadmill-based gaits produced similar waveform shapes. Of the 3 planes of motion evaluated, only sagittal plane kinematic gait data were unaffected by mode of ambulation as determined via Fourier analysis. Sagittal kinematic gait data collected from dogs during overground or treadmill-based ambulation were comparable. However, analysis methods may affect data comparisons.
In vitro effects of lipid emulsion on platelet function and thromboelastography in canine blood samples
Authors: Tonkin Laura R. , Parnell Nolie K. , Hogan Daniel F. 
Published: March 2013

Abstract
Objective—To determine whether soybean oil emulsion has an in vitro effect on platelet aggregation and thromboelastography in blood samples obtained from healthy dogs.
Animals—12 healthy adult dogs.
Procedures—Blood samples were collected from each dog into tubes containing EDTA, hirudin, or sodium citrate for a CBC, collagen- and ADP-induced impedance aggregometry, or thromboelastography, respectively. Whole blood platelet aggregation, determined with ADP or collagen agonists, was measured in blood samples containing hirudin and final lipid concentrations of 0, 1, 10, and 30 mg/mL. The thromboelastographic variables R (reaction time), K (clotting time), α angle, and maximum amplitude were evaluated in blood samples containing sodium citrate and final lipid concentrations equivalent to those used for assessment of platelet aggregation.
Results—Median maximum ADP- and collagen-induced platelet aggregation in blood samples containing 1, 10, or 30 mg of lipid/mL did not differ significantly from the value for the respective lipid-free blood sample. Maximum amplitude determined via thromboelastography was significantly reduced in blood samples containing 10 and 30 mg of lipid/mL, compared with findings for lipid-free blood samples. Values of other thromboelastographic variables did not differ, regardless of lipid concentrations.
Conclusions and Clinical Relevance—Maximum amplitude determined via thromboelastography in canine blood samples was significantly affected by the addition of lipid to final concentrations that are several orders of magnitude higher than clinically relevant lipid concentrations in dogs. Lipid treatment appears to have no significant effect on hemostatic variables in dogs, although clinical studies should be performed to confirm these in vitro findings.