bluuebunny/crossref_metadata_2025_split huggingface dataset:
Step Change Jar Technology Redefines Industry Standards in North Sea Region
Authors: Herrington D. , Barton S. , Bouaziz S. , Clausen J. 
Published: October 2012

Abstract
While jar technology has been used in the oil industry for the better part of the last century, the basic function and capability has not taken many leaps forward. Increasingly complex well geometry and deeper target depths continue to push drillers into tighter, higher risk well conditions that raise the probability of stuck pipe events. As demand for hydrocarbons has forced our drilling capabilities to evolve, the increased risk associated with these wells has forced the evolution of jarring technology to drastically evolve.
By assessing the critical needs of the industry, a jar has been designed to operate in the harshest environments, with superior reliability, and the highest firing loads available to increase the levels of success in freeing a drill string during a stuck pipe event. Every pound of impact force delivered is critical to improve the chances of retrieving the drill string safely to surface and this new technology has raised the standard force by as much as 20%.
While the operation of this innovative technology remains consistent with industry standards, the performance in regards to torsional strength, damage resistance, and impact capabilities far exceed that of previously existing jar technology. An optional performance component offers operators a safeguard against pulling the jar beyond its mechanical and hydraulic limits which can render it useless down hole. In addition to safeguarding the tool from damage, this module also allows the tool to be pulled to its maximum rating, every time, insuring the hardest possible impact every pull.
This paper will detail how the use of this innovative tool has provided flawless performance in the North Sea and offers a true step change in jar technology to the drilling industry. Case studies and field data provided will support and demonstrate increased performance unmatched in the industry today.
Innovative Solution Successfully Recompletes Problematic Well in Malaysia
Authors: Elliott Chris , Mahzan Mohammad , Feroze Mohd Imran , Mahadi Khairul Azmi , Mahdzan Abdil Adzeem , Aziz Khairil Faiz , Forbes Murray , Dzul-Fikar Nasri 
Published: October 2012

Abstract
An offshore operator in Malaysia had run a completion string in a highly deviated 7-in. gas well. When continuous pressure build-up in the production casing annulus was observed during well clean-up, leakage in the completion system was suspected. After several attempts to mitigate the pressure build-up failed, the operator initiated further investigation, which confirmed the suspicion. Small tubing leaks that were allowing produced gas inside the tubing to seep through to the annulus were found. These leaks could have allowed the pressure to increase, and possibly, could have caused the casing to collapse. In order to produce through the annulus, the pressure would have to be vented. With the high demand of gas in Malaysia and since the rig was still at the location, the project team decided to initiate immediate recompletion of the project instead of waiting for a later intervention.
This well is one of three wells completed to develop the FN field within KCL area, located approximately 200 km offshore from Bintulu. The field was expected to deliver up to 100mmscf/day per well to help relieve an anticipated gas shortage.
This paper discusses the history of the wells, the diagnostic methods used to analyze the well problems, the pros and cons of each solution considered, details regarding the recompletion chosen, and the challenges encountered during the recompletion activities. The discussion also highlights the successful solution used for closing and reopening the fluid loss isolation barrier valve (FLIBV) with a wireline tractor rather than with other options considered after conducting a successful system integration test (SIT) prior to the project execution. The unique solution chosen was a first for Malaysia, and probably, for the world.
The success of the recompletion results provided improvements for future applications and will be a benchmark solution for future operations.
A Comprehensive Evaluation of the Performances of Alkaline/Surfactant/Polymer in Conventional and Unconventional Reservoirs
Authors: Dang Cuong T. , Nguyen Ngoc T. , Chen Zhangxin (John) , Nguyen Huy X , Bae Wisup , Phung Thuoc H. 
Published: October 2012

Abstract
Chemical flooding, especially alkaline/polymer/surfactant (ASP) flooding is of significant increasing interest in mature reservoirs because of high oil prices and larger energy demands. However, it is a very complicated process, and the success of ASP has been mostly demonstrated in laboratory scale. Additionally, ASP is very sensitive to reservoir heterogeneity; therefore, it is urgent and necessary to have a comprehensive investigation of ASP flooding in different reservoir types for a wider and more successful implementation.
This paper aims to solve the prior problems for achieving a new insight vision of ASP flooding. Firstly, a series of laboratory experiments were conducted to optimize the ASP solution. A new mixture of single and double tail anionic surfactant was proposed as a promising approach for high temperature and hardness reservoirs. These mixtures are also more compatible with polymer and increase the optimum salinity. All of the important factors such as alkaline/polymer/surfactant concentration, pH, temperature, salinity, ionic strength were taken in account. And, the experimental result was analyzed by experimental design techniques which allow for evaluating the interaction among those factors which were usually eliminated in literature.
Based on these above achievements in laboratory, full fields scale simulations have been done to assess the performance of ASP in various real field conditions from conventional to unconventional reservoirs which are including traditional sandstone reservoir, tight sandstone oil reservoir, naturally fractured basement reservoir. As an observation result, ASP flooding brings a higher oil recovery (about 10 to 28%), and lower water cut than traditional waterflooding in all of four case studies. However, the incremental amount is not similar since geology characteristics have strong effects on ASP process. The simulation result proved that the fractured reservoirs with low matrix permeability are not suitable candidates for ASP. On the contrary, ASP has great potential for enhancing heavy oil recovery, especially in small and thin reservoirs. A sensitivity analysis was performed for determining the optimal ASP solution and injective scheme for each reservoir condition.
The First Real Time Logging with Coiled Tubing Tractor in an Extended Reach Horizontal Well with Proof of True Stimulation
Authors: Arukhe James , Dhufairi Mubarak , Ghamdi Saleh , Duthie Laurie , Omairen Khalid 
Published: October 2012

Abstract
The world's first successful application of a wired motor head assembly to allow real time logging with a tractor in an extended reach open hole horizontal well has been recorded in Saudi Arabia. The well, located on one of two finger islands, was completed to a total depth of 29,897 ft. (9.11 km) MD; making it the deepest well with open-hole section in the field development, and outside of the reach of traditional tapered coiled tubing (CT) used for well intervention.
Using 2 inch tapered coil tubing and well tractor, the well was successfully acid-stimulated in 14 stages with a total of 3,850 barrels of (diesel) emulsified HCl acid recipe. This paper shows that although tractor interventions have a proven record and are the preferred deployment method for extended well stimulation, there still existed the uncertainty of conducting real time production logging while simultaneously tractoring. This additional challenge in the industry could be overcome by utilizing real time Electrical to Optical (EtO) production logging measurements simultaneously with the running of a tractor. A comparison of the pre- and post-stimulation injectivity indices on a separate run prior to the real time production log acquisition showed an eight fold injectivity index improvement from 53 bpd/psi to 400 bpd/psi. The resulting marked injectivity improvement from acid stimulation also showed the benefit of informed decisions from real time fiber-optic distributed temperature system (DTS) in fluid placement.
Practical applications of these outcomes include the acquisition of real time data of comparable quality with conventional e-line tools resulting in distinct technical and economic advantages in the development of the remaining parts of the field.
Others include the reduction in total well delivery costs from an ability to accurately evaluate well performanceand diagnose problems in real time. The ability to employ real time information to effectively stimulate extended reach wells provide assurance that stimulation can serve as a technical and an economic solution for addressing the relatively high skin damage problem post drilling and completion. Real time logging with the tractor is logistically efficient and allows real time acquisition of injection profiles with the possibility for improving data quality with return passes.
Qualification, Verification and Validation of Novel Subsea Tooling
Authors: Wilkinson David , Wagstaff Mark 
Published: October 2012

Abstract
This paper describes the design, development and testing of a set of diver operated subsea tooling used to resolve a unique issue that occurred during the construction of two subsea wells installed by Esso Australia in 95 metres of water, off the coast of south-eastern Australia.
By following a structured and rigorous process of qualification, verification and validation it was possible to successfully develop the required tooling on a fast track basis in order to meet the schedule constraints of the on-going diving support vessel campaign.
A Western Australia based company with design and manufacturing capability and demonstrating expertise in the development of comparable customised subsea equipment was selected to supply the required tooling. A considerable number of technical solutions were evaluated during the concept development phase prior to selecting a single optimised concept and finalising the design of the tooling.
Comprehensive onshore testing of the tooling and involvement of the diving personnel were essential steps in maximising the probability that the offshore operations could be executed in a safe and efficient manner. As a result of these efforts the tooling operated flawlessly in the field and a multi-million dollar re-drill campaign was avoided.
This paper focuses on the steps undertaken in each part of the qualification, verification and validation process, in order to use this work as an example of the activities that are typically involved in each of these steps, and thus provide a roadmap for the application of this process in other time critical, high consequence situations.
Rate and Determinants of Association Between Advanced Retinopathy and Chronic Kidney Disease in Patients With Type 2 Diabetes
Authors: Penno Giuseppe , Solini Anna , Zoppini Giacomo , Orsi Emanuela , Zerbini Gianpaolo , Trevisan Roberto , Gruden Gabriella , Cavalot Franco , Laviola Luigi , Morano Susanna , Nicolucci Antonio , Pugliese Giuseppe ,   for the Renal Insufficiency And Cardiovascular Events (RIACE) Study Group
Published: October 2012

OBJECTIVE
To evaluate the rate and determinants of concordance between advanced diabetic retinopathy (DR) and chronic kidney disease (CKD), as assessed by both albuminuria and estimated glomerular filtration rate (eGFR), in the large cohort of the Renal Insufficiency And Cardiovascular Events (RIACE) Italian multicenter study.

RESEARCH DESIGN AND METHODS
Patients with type 2 diabetes (n = 15,773) visiting consecutively 19 hospital–based diabetes clinics in years 2007 and 2008 were examined. DR was assessed by dilated fundoscopy. CKD was defined based on albuminuria and eGFR.

RESULTS
CKD was present in 58.64% of subjects with advanced DR, whereas advanced DR was detectable only in 15.28% of individuals with any CKD and correlated with the albuminuric CKD phenotypes more than with the nonalbuminuric phenotype. Age, male sex, diabetes duration, hemoglobin A1c, hypertension, triglycerides, previous cardiovascular disease, and, inversely, HDL-cholesterol correlated independently with the presence of any CKD in individuals with advanced DR; correlates differed according to the presence of albuminuria, reduced eGFR, or both. Conversely, factors associated with the presence of advanced DR in subjects with any CKD were diabetes treatment, previous cardiovascular disease, albuminuria, and, inversely, smoking, eGFR, and age at diagnosis.

CONCLUSIONS
Concordance of CKD with advanced DR is low in subjects with type 2 diabetes, and CKD without advanced DR is more frequent than isolated advanced DR, at variance with type 1 diabetes. Factors independently associated with the presence of any CKD in individuals with advanced DR differ, at least in part, from those correlating with the presence of advanced DR in subjects with any CKD and by CKD phenotype.
Cuspal Deflection in Premolar Teeth Restored Using Current Composite Resins With and Without Resin-modified Glass Ionomer Liner
Authors: Karaman E , Ozgunaltay G 
Published: October 2012

SUMMARY
Aim: To evaluate the effects of four different types of composite resins and a resin modified glass ionomer cement (RMGIC) liner on the cuspal deflection of large MOD cavities in vitro. Materials & Methods: One hundred twenty-eight extracted human upper premolar teeth were used. After the teeth were divided into eight groups (n=16), standardized large MOD cavities were prepared. The distance between cusp tips was measured before and after the cavity preparations with a digital micrometer. Then the teeth were restored with different resin composites (Filtek Supreme XT, Filtek P60, Filtek Z250, Filtek Silorane - 3M ESPE, St Paul, MN, USA) with and without a RMGIC liner (Vitrebond, 3M ESPE, St Paul, MN, USA). Cuspal deflection was measured 5 min, 24 h, and 48 h after the completion of restorations. The data were statistically analyzed with Friedman and Kruskal Wallis tests. Results: A significant reduction in cuspal deflection was observed in Filtek Silorane restorations with and without RMGIC liner (p&lt;0.05). In all restored teeth, the distance between cusps was reduced but they did not return to their original positions during the 48 h period. All teeth showed cuspal deflection, but placement of RMGIC liner reduced it. Conclusion: The use of silorane-based composites and the placement of RMGIC liner under the composite resin restorations resulted in significantly reduced cuspal deflection.
Effect of Chlorhexidine Application on the Long-term Shear Bond Strength to Dentin of a Resin-modified Glass Ionomer
Authors: Dursun E , Le Goff S , Ruse DN , Attal JP 
Published: October 2012

SUMMARY

Purpose
The aim of this study was to investigate the effect of chlorhexidine digluconate (CHX) application on the shear bond strength (SBS) of a resin-modified glass ionomer cement (RMGIC) to polyalkenoic acid–preconditioned dentin after 24 hours, six months, and 12 months of water storage at 37°C.

Materials and Methods
Cylindrical molds, placed on flat, polyalkenoic acid (Cavity Conditioner® [GC]) preconditioned dentin surfaces of 90 human teeth embedded in resin, were filled with Fuji II LC® (GC), a RMGIC, with (n=45) or without (n=45) the prior application of a 0.05% CHX solution. Within each group, SBS was determined after 24 hours (n=15), six months (n=15), and 12 months (n=15) of storage in water at 37°C. The results were analyzed with two-way analysis of variance followed by Tukey multiple means comparisons (p&lt;0.05). The type of bond failure (adhesive/cohesive/mixed) was noted and the results were analyzed with chi-square test (p&lt;0.05).

Results
After 24 hours, the SBS of RMGIC was not significantly different with (9.0 ± 2.8 MPa) or without (8.3±0.6 MPa) the application of CHX. After six months, however, SBS increased significantly in the group without CHX (12.7±3.4 MPa) but remained unchanged in the CHX group (9.4±4.0 MPa). Similar results without CHX (12.6±3.8 MPa) and with CHX (9.5±3.2 MPa) were obtained after 12 months. No significant differences in the type of debonding were found between the various groups tested.

Conclusion
The application of 0.05% CHX after dentin preconditioning did not seem to have affected the 24-hour SBS of RMGIC. However, the six- and 12-month SBS was significantly lower for CHX-treated samples, possibly as a result of CHX interference with both the bonding mechanism and the maturation reaction of RMGIC.
Temperature Increase at the Light Guide Tip of 15 Contemporary LED Units and Thermal Variation at the Pulpal Floor of Cavities: An Infrared Thermographic Analysis
Authors: Gomes M , DeVito-Moraes A , Francci C , Moraes R , Pereira T , Froes-Salgado N , Yamazaki L , Silva L , Zezell D 
Published: October 2012

SUMMARY
In this study, a comprehensive investigation on the temperature increase at the light guide tip of several commercial light-emitting diode (LED) light-curing units (LCUs) and the associated thermal variation (ΔT) at the pulpal floor of dental cavities was carried out. In total, 15 LEDs from all generations were investigated, testing a quartz-tungsten-halogen (QTH) unit as a reference. The irradiance level was measured with a power meter, and spectral distribution was analyzed using a spectrometer. Temperature increase at the tip was measured with a type-K thermocouple connected to a thermometer, while ΔT at the pulpal floor was measured by an infrared photodetector in class V cavities, with a 1-mm-thick dentin pulpal floor. The relationship among measured irradiance, ΔT at the tip, and ΔT at the pulpal floor was investigated using regression analyses. Large discrepancies between the expected and measured irradiances were detected for some LCUs. Most of the LCUs showed an emission spectrum narrower than the QTH unit, with emission peaks usually between 450 and 470 nm. The temperature increase at the tip followed a logarithmic growth for LCUs with irradiance ≥1000 mW/cm2, with ΔT at the tip following the measured irradiance linearly (R2=0.67). Linear temperature increase at the pulpal floor over the 40-second exposure time was observed for several LCUs, with linear association between ΔT at the pulpal floor and measured irradiance (R2=0.39) or ΔT at the tip (R2=0.28). In conclusion, contemporary LED units show varied irradiance levels that affect the temperature increase at the light guide tip and, as a consequence, the thermal variation at the pulpal floor of dental cavities.
The Effect of a 10% Carbamide Peroxide Bleaching Agent on the Microhardness of Four Types of Direct Resin-based Restorative Materials
Authors: AlQahtani MQ 
Published: October 2012

SUMMARY

Purpose
This in vitro study was undertaken to evaluate the effect of a 10% carbamide peroxide bleaching agent on the microhardness of four types of direct resin-based restorative materials.

Materials and Methods
Thirty disk-shaped specimens (10.0 mm diameter × 2.0 mm depth) of each material, including a microhybrid resin composite (Z250), a nanofilled resin composite (Z350), a silorane-based low-shrink resin composite (P90), and a hybrid resin composite (Valux Plus), were fabricated and then polished with medium, fine, and superfine polishing discs. After being polished, specimens were cleaned with distilled water for 2 min in an ultrasonic bath to remove any surface debris and then stored in distilled water at 37°C for 24 hours. Specimens from each material were divided into three groups (n=10). One group was selected as a control group (nontreated with bleaching agent). The other two groups were treated with bleaching agent for 14 days (group A) and for 14 days followed by immersion in artificial saliva for 14 days (group B). The top surfaces of the specimens in the different groups were also subjected to the Vickers hardness test with a load of 300 g and 15-second dwell time. Data were analyzed with a one-way analysis of variance and Tukey's HSD test (α = 0.05).

Results
There was a general reduction of Vickers hardness numbers (VHN) values of treated groups compared with the control group for each material used, but this reduction was minimal, with no significant difference between groups in Z250, whereas the other three materials (Z350, P90, and Valux Plus) showed a significant reduction of VHN of treated groups compared with the control group. Conversely, the findings showed no significant difference between treated groups A and B in all materials used except P90.

Conclusion
A 10% carbamide peroxide bleaching agent had an adverse effect on the microhardness of nanofilled, silorane-based low-shrink, and hybrid types of resin-based composite materials compared with the microhybrid type.
Dimensional Accuracy of Optical Bite Registration in Single and Multiple Unit Restorations
Authors: Iwaki Y , Wakabayashi N , Igarashi Y 
Published: October 2012

SUMMARY
The dimensional accuracy of optical bite registration in the CEREC system was compared to that of the conventional physical method in vitro using a bite registration material. Maxillary and mandibular full-arch dentate epoxy models mounted on an articulator were used to measure the interarch distance and the angles created by the occlusal planes. The preparations for a single restoration on the maxillary first molar or for multiple restorations on the maxillary posterior quadrant were made on the model. Optical impression and bite registration data were collected to construct virtual models using computer-aided design software. A silicone material was used for the physical method, and the dimensional accuracy was measured by means of the coordinate measuring machine. The discrepancy relative to the baseline before preparation was analyzed in each registration record. For the single restoration, the optical method created a mean discrepancy of 243.2 μm relative to baseline at the prepared tooth, which was insignificantly but slightly lower than the mean discrepancy of 311.1 μm obtained with the physical method. The mean rotational deviation in the horizontal plane was significantly lower for the optical method. For the multiple preparations, the optical method showed significantly larger discrepancy on the right molar and on the left premolar and molar sites. In the frontal view, the optical method created significantly larger rotational deviation than the physical method. The result indicates that the optical bite registration was effective in terms of dimensional accuracy for single posterior restorations.