bluuebunny/crossref_metadata_2025_split huggingface dataset:
Management commitment influence on implementation of occupational health and safety policies in water and sanitation companies in Nyeri County, Kenya
Authors: Nderitu Rachel , Mwaura Peter , Gichuhi David 
Published: November 2019

Contemporary employees spend most of their working lives in the workplace. Work provides economic, social and psychological experiences that promote the mental wellbeing of individuals. The work environment should be devoid of hazards as much as possible to provide healthy and decent work for the workforce. However, numerous injuries, illnesses, property damages, and process losses take place at different workplaces. It is unclear how effectively OSH programs are being implemented in Kenya’s water sector since no study has been done. The general objective of the study was to establish an influence of management commitment on Occupational Health and Safety policies implementation in Water and Sanitation Companies in Kenya, a study of water and Sanitation Companies in Nyeri County. The study was based on the theoretical foundation that comprises two theories Leader-Member Exchange theory and Bourgeois and Brodwins Five Models of Strategy Implementation. The target population consisted of 474 employees in all water & sanitation companies in Nyeri County. From this population, a sample of 243 respondents was drawn using a random sampling technique but only 188 respondents filled and returned valid questionnaires giving the study an 80% response rate. The study employed both descriptive and inferential statistics to present and analyze the data. Quantitative data was analyzed using descriptive statistical tools namely frequencies, percentages, mean and standard deviation while inferential statistical tools such as multiple regression were used to determine the relationship between variables. The study findings revealed that there was a statistically significant positive relationship between management commitment and implementation, the 27.9% unit change in the implementation of OSH policies was explained by the management commitment. The study recommends that the water companies’ management should be committed to the implementation of OSH.
Improving the Diagnosis of Ipsilateral Femoral Neck and Shaft Fractures
Authors: Rogers Nathan B. , Hartline Braden E. , Achor Timothy S. , Kumaravel Manickam , Gary Joshua L. , Choo Andrew M. , Routt Milton L. , Munz John W. , Warner Stephen J. 
Published: November 2019

Background:
Despite increased awareness of ipsilateral femoral neck fractures in patients with high-energy femoral shaft fractures and advanced imaging with thin-cut high-resolution computed tomography (CT), failure of diagnosis remains problematic. The purpose of the present study was to determine if the preoperative diagnosis of ipsilateral femoral neck fractures in patients with high-energy femoral shaft fractures can be improved with magnetic resonance imaging (MRI) compared with radiographic and CT imaging.

Methods:
In response to delayed diagnoses of femoral neck fractures despite thin-cut high-resolution CT, our institutional imaging protocol for acute, high-energy femoral shaft fractures was altered to include rapid limited-sequence MRI to evaluate for occult femoral neck fractures. All patients received standard radiographic imaging as well as thin-cut high-resolution pelvic CT imaging upon presentation. Rapid limited-sequence MRI of the pelvis was obtained to evaluate for an occult femoral neck fracture.

Results:
Thirty-seven consecutive patients with 39 acute, high-energy femoral shaft fractures resulting from blunt trauma were included. The average age of the patients was 29.1 years (range, 14 to 82 years). Ten (25.6%) of the 39 femoral shaft fractures were open. Two femoral shaft fractures (5.1%) were associated with ipsilateral femoral neck fractures that were detected on radiographs, and no MRI was performed. None of the remaining 37 femoral shaft fractures were associated with a femoral neck fracture that was identified on CT imaging. Thirty-three (89.2%) of 37 patients underwent pelvic MRI to evaluate the ipsilateral femoral neck. Four (12.1%) of those 33 patients were diagnosed with a femoral neck fracture (2 complete, 2 incomplete) that was not identified on thin-cut high-resolution CT or radiographic imaging.

Conclusions:
Rapid limited-sequence MRI of the pelvis for patients with femoral shaft fractures identified femoral neck fractures that were not diagnosed on thin-cut high-resolution CT in 12% of our patients. Our results suggest that the frequency of femoral neck fractures may be underrepresented on CT imaging; rapid limited-sequence MRI was feasible without delaying definitive treatment even in polytraumatized patients.

Level of Evidence:
Diagnostic Level III. See Instructions for Authors for a complete description of levels of evidence.
Anatomical Implications Regarding Femoral Nerve Palsy During a Direct Anterior Approach to Total Hip Arthroplasty
Authors: Yoshino Kensuke , Nakamura Junichi , Hagiwara Shigeo , Suzuki Takane , Kawasaki Yohei , Ohtori Seiji 
Published: November 2019

Background:
Femoral nerve palsy is a serious neurological complication following total hip arthroplasty (THA) via a direct anterior approach. One hypothesis is that the nerve injury is caused by malpositioning of retractors over the anterior wall of the acetabulum. The purpose of this cadaveric study was to clarify the anatomical features of the femoral nerve around the anterior acetabular rim and the potential risk of nerve injury during a direct anterior approach to THA.

Methods:
We dissected 84 cadaveric hips from 44 formalin-embalmed cadavers. When the cadavers were supine, the iliopsoas muscle and the femoral nerve were exposed and the anterior joint capsule and labrum were resected. The measurement points were determined along the acetabular rim every 30°, and a reference line was drawn from the anterior superior iliac spine to the center of the acetabulum, with the intersection of the rim at 0°. The minimum distance to the femoral nerve margin was measured from 0° to 150° (6 points). Other anatomical structures were measured to determine their association with the distance of the shortest measurement points.

Results:
The mean minimum distances to the femoral nerve were 33.2 mm at 0°, 24.4 mm at 30°, 18.4 mm at 60°, 16.6 mm at 90°, 17.9 mm at 120°, and 23.2 mm at 150°, showing that the distance at 90° was the shortest (p < 0.001). The thickness of the iliopsoas muscle and the femoral length were positively associated with the distance to the femoral nerve at 90°.

Conclusions:
In this cadaveric study, the femoral nerve was within 16.6 to 33.2 mm of the acetabular rim at points from 0° to 150° of a line drawn from the anterior superior iliac spine. The nerve was closest to the rim at 90°, indicating that this is an area of high risk during retractor placement.

Clinical Relevance:
Retractor placement at 90° to the anterior acetabular rim should be avoided to reduce the risk of femoral nerve injury.
Quantifying 2D and 3D Fracture Leakage Pathways Observed in Wellbore Cement after Uniaxial Compressive Loading
Authors: Yang Xinxiang , Kuru Ergun , Gingras Murray , Iremonger Simon , Taylor Jared , Lin Zichao 
Published: November 2019

Abstract
Stress-induced fractures in wellbore cement can form high-risk pathways for methane or carbon dioxide leakage yet little to no quantitative information on the impact of these fractures has been reported. To investigate this, scanning electron microscopy (SEM) and micro computed tomography (micro-CT) techniques were utilized to quantify the 2D and 3D geometrical parameters of cement fractures in mature thermal thixotropic cement samples that were subjected to pre- and post-peak compressive stress. A novel simulation method was also proposed to quantify the impact of the stress-induced realistic 3D fractures on the cement permeability.
Results show that: i-) For pre-peak samples, 90% of the 2D fractures have length and width smaller than 100 μm and 5 μm, respectively. Although higher compressive stress reshaped the 3D fractures and increased the fracture length and width, no well-propagated fractures were observed; ii-) For post-peak samples, distinctly visible (&gt; 0.1 mm) well-propagated fractures were generated but failed to penetrate the entire sample, therefore the effect of stress-induced fractures (up to 1.0% strain) on cement sample's permeability is limited; and iii-) CT-based 3D visualization and simulation both show that inclusion of a correctly engineered fiber additive is able to blunt the fracture propagation in cement samples.
We conclude that up to the uniaxial compressive strength, the monotonic compressive stress is not likely to create leakage pathways in wellbore cement since the 2D fractures observed in SEM images are in limited dimensions and the large 3D fractures characterized in CT images have poor connectivity. Inclusion of a fiber additive is expected to enhance cement integrity by limiting the fracture propagation.
Sources of Strain Localization in Thermal Wells and Managing the Risks they Introduce through Engineering Design
Authors: Miller Samantha M. , Smith Kelcie T. , Chartier Mark A. , Meijer Garret 
Published: November 2019

Abstract
Pipe installed in thermally stimulated wells is subject to high axial loads arising from the combination of axial constraint and temperature changes. These axial loads are manifested as applied strains, which are a function of the material thermal expansion behaviour, rather than applied loads. Variations in tubular strength and stiffness act to redistribute these strains and, in some cases, cause local strains to be significantly higher than the global average. This ‘strain localization’ can be particularly pronounced when the temperature change is sufficient to yield the pipe body and when the system is subject to variations in tubular constraint.
The energy industry has identified that a robust design must account for strain localization (DACC IRP3, 2012). However, at present there is no industry accepted practice for characterizing the potential for strain localization and selecting appropriate design margins to protect casing from damage.
This paper provides an overview of strain localization in thermal well tubulars including discussion of the sources of constraint in both casing and liner, and discussion of the mechanisms that can trigger and exacerbate strain localization. The authors propose an analytical solution to calculate strain localization magnitude under basic conditions and demonstrate finite element methods for handling complex string designs and configurations. Finally, a case study provides an example of how the methods can be used to optimize string design to reduce the likelihood of problematic strain localization.
The discussion and finite element results provide an enhanced understanding of the mechanisms that will lead to strain localization and, in turn, provide guidance on what conditions to consider in the design of thermally stimulated wells. The analytical approach provides a practical approach to rapidly assess potential strain localization scenarios and ensure that those posing particular risk can be either characterized more rigorously or re-designed to minimize failure potential.
Well Integrity Issues: Extreme High-Pressure High-Temperature Wells and Geothermal Wells a Review
Authors: Phi Thai , Elgaddafi Rida , Al Ramadan Mustafa , Ahmed Ramadan , Teodoriu Catalin 
Published: November 2019

Abstract
Most untapped promising energy resources in the world are associated with extreme downhole environment conditions. Applying the conventional method of well construction and operation for extreme downhole conditions poses severe challenges for the safety and longevity of the well. Governments and independent standardization organizations have developed several regulations regarding maintaining well integrity. Nevertheless, methods of completing and operating Extreme High-Pressure-High-Temperature (XHPHT) wells as well as geothermal wells have not yet been standardized. Preserving well integrity throughout the life cycle of a well is very crucial. Failure in well integrity can lead to huge operational and environmental risk and increase the energy cost.
This paper critically reviews the causes and solutions of well integrity issues in XHPHT and geothermal wells. After giving an overview of these wells, the paper discusses the well barriers at different ages. It also presents the conditions that lead to well integrity issues. Furthermore, the article discusses comprehensively the influence of acidic environment on cement and casing degradation at HPHT and summarizes the most recent research findings and development strategies in mitigating the integrity issues.
Previous studies revealed that the integrity of well barriers is highly affected by the degradation of drilling and completion fluids, cement, and tubular materials. The main causes of the well integrity loss are the lack of understanding of downhole conditions, inappropriate well construction practices, poor selection of the casing material and cementing type as well as inadequate design verification and validation on the downhole specimen. The well barriers are inter-related to each other as the destruction of one barrier may lead to the dismantling of the entire well barrier envelope. The XHPHT and geothermal wells share numerous similar barrier integrity issues, but they also have some unique problems due to the nature of their own operations. Although there is a significant advancement in solving the well integrity issues for the extreme downhole conditions, a sizable technology gap still exists in constructing and operating XHPHT and geothermal wells.
The current market conditions and the advancement in technologies are making the development of XHPHT wells more economically feasible. This paper serves as a review of the current research and development regarding well integrity issues for XHPHT and geothermal wells.
Application of High Temperature Coatings for Near-Surface Corrosion Mitigation on SAGD Wells
Authors: Khallad Isaac , Habib Mohamad , Savino Vincenzo 
Published: November 2019

Abstract
Near-surface casing corrosion has been observed to occur on operating steam-assisted gravity drainage (SAGD) wells in the Surmont field. The corrosion issue could pose risks to containment assurance and have negative implications on well economics throughout the life cycle. This paper discusses how the corrosion was first identified and then successfully mitigated using a high temperature coating solution on the production casing. The methodology used for coating testing, evaluation, and selection is also discussed.
A two-tiered testing program was developed to qualify suitable coatings for the Surmont application. Eleven coating systems from various suppliers were first tested in the lab in a screening exercise to identify the best-in-class coatings for further evaluation. The top six performing coatings were then tested in the field environment to complete the evaluation. Coating performance was evaluated using a series of standard test methods.
Out of the eleven candidate coatings, only two coatings qualified for the high temperature application in Surmont. These coatings are expected to provide long-term corrosion protection of the production casing at an optimized cost. One of these two coatings was successfully applied on an operating well and has provided reliable corrosion protection after four years of service.
The methodology discussed in this paper for coating evaluation and application has been successfully implemented in the Surmont field. The findings from this work can be used to mitigate near-surface corrosion which will result in improved containment assurance and well economics.
Double Barrier Strategy for Heavy Oil Producer Well in the South of Oman
Authors: Al Shizawi Wafa , Al Nairi Aadil , Cooper Allan , Al Mahrazy Khalfan , Putra Pristiwanto 
Published: November 2019

Abstract
The first phase of steam flood development has been successfully implemented in a Petroleum Development Oman (PDO). The oil producer wells are completed with a single mechanical barrier as they are classified as low risk (not having a potential to self-flow to surface as the target formation is under pressured). However, in the later stages of development, steam break through into the producer occurs and must be managed to maximize production and increase recovery rates. To avoid gas-lock of the production pump, a fluid level is maintained in the wellbore by producing the steam up the production annulus, a production strategy referred to as casing venting. Implementing this strategy causes the producer wells to be capable of self flowing if steam injection is maintained. A well capable of self flowing to surface is classified as medium risk and requires two barriers.
For phase 2 of the project, expansion of the field to the North and South, the producer wellheads will have a Hydraulic Surface Annulus Safety Valve (H-SAS) system installed in the VR profile on either side of the A-anulus (right & left) as the primary barrier. The SOV's (Side Outlet Valve) will be the second barrier.
The H-SAS system was developed to assure and enhance annulus integrity. As part of the capabilities, the utilization of this safety device allows pressure management and operational venting within the annulus while providing a barrier in the event of an incident. The new wellhead design will meet the well compliance requirements and also allow for casing venting during operation.
Best Practices in Design of Steam Splitters for Steam-Assisted Gravity Drainage Injection Wells
Authors: Nascimento Carlos , Gomez Bustamante Nicolas , Melo Marco 
Published: November 2019

Abstract
Steam-assisted gravity drainage (SAGD) is the most common recovery method for bitumen reservoirs in Western Canada. This method basically consists of a producer and injector, built in parallel, one on top of the other. During the normal operation phase (or SAGD mode), the top well injects steam into the reservoir whereas the bottom one produces bitumen, water, and gas. In the injector well, it is common to consider steam splitters to better manage the steam injection along the reservoir and minimize the required injection pressure at surface. This paper reviews steam splitter application in SAGD injection wells in Western Canada and describes the best practices to achieve appropriate distribution of steam in the horizontal section, gathered after designing dozens of wells in the region and considering the implications of two-phase flow and effective heat transfer in tubulars and the reservoir. Several studies were done for one well using a multiphase flow simulator, including the design of the number of ports, steam flow rate sensitivity, injection only in the tubing and combined injection in tubing and casing, the number of steam splitters, and reservoir heterogeneity. The results are shown in terms of the designed number of ports and steam distribution in each steam splitter, required injection pressure, pressure and temperature profiles, and so on. These results will provide operators with additional insights into the downhole behavior of the horizontal steam injection well, leading to improved performance of SAGD processes and identification of possible challenging operational conditions.
Horizontal Steam Injection Liner Deployed Flow Control Device Design Development and Testing
Authors: Gorham Timothy , Sims Jackie , Buell R. Scot , Miller Roger , Fermaniuk Brent , Heukelman Herman 
Published: November 2019

Abstract
Controlling steam conformance in the horizontal injectors of SAGD projects is widely accepted as being critical for commercial success. This work is focused on steam distribution in horizontal injectors in mobile, heavy oil (non-bitumen), thermal development projects. Steam Conformance can be achieved by tubing or liner deployed FCD's (flow control devices). Liner deployed FCD's have several advantages over tubing-deployed FCD's which includes: smaller tubulars, lower capital costs, reduced well interventions, and potentially reduced surveillance requirements.
This paper provides an overview of a collaborative development methodology for liner-deployed FCD's in horizontal steam service between a service company and operator. This methodology included: Establishing functional, operational and dimensional basis of designComputational fluid dynamics (CFD) analysis of the FCD design and phase-split testing in the Horizontal Steam Injection Test Facility (HSITF)Design revisions based on CFD, HSITF and shift testing resultsField installations results based upon fiber optic, thermo-hydraulic, and mechanical analysis
These FCD's were designed with sliding-sleeve technology to enable opening or closing of each device. Different specifications of electroless nickel (EN) coatings were also tested to determine the performance for scaling and corrosion resistance. Within 6 months, three versions of the FCD's were tested in the HSITF with accompanying CFD. For each version the shifting forces before and after ~6 weeks of steam injection were measured. Each generation was improved based on the data from the prior version.
In December 2018, three FCD's were installed in a large bore horizontal steam injector in a tubing deployed completion for field qualification of the devices. This installation was the first step of a one-year field qualification test. The full test will involve multiple interventions to opening and closing the FCD's. A capillary tubing with fiber optic wrapped around the tubing and devices can confirm FCD openings or closings. The field qualification will also test the local operational capability to shift the FCD's. At the end of the field qualification, the flow devices will be retrieved for inspection and identification of further design improvements.
Evaluating Temperature Rate near the Wellbore Considering Slow Warm-Up Case for a Sagd Producer Well with Different Completion Configurations Using Dynamic Flow Simulations
Authors: Nascimento Carlos , Demirdal Barkim , Gauthier Joshua 
Published: November 2019

Abstract
Temperature and pressure changes are drastic during the warm-up phase (steam circulation) of SAGD wells as a result of introducing heat to cold tubulars. These drastic changes will impact casings as well as cement. Impacts of circulation strategy (fast vs. slow warm-up) for 11 ¾ in. intermediate casing with dual parallel completion design, on cement and casing were investigated previously. Current work focused on analyzing the impact of slow warm-up on smaller intermediate casing size (9 5/8 in.) for dual parallel and single string completion designs, the second one with vacuum insulation tubing (VIT).
The purpose of this paper is to complement the results of previous work in terms of using transient analysis to assess the impact of warm-up rates. The results of transient flow simulator data together with field data enable determining the effect of the warm-up period on different components of wellbore for different types of completions (small versus large wellbore, single versus dual string, uninsulated versus insulated tubing) from integrity perspective.
In this study, the dynamic flow simulations indicated that time for steam to reach the toe was almost the same for the dual string and the single string with VIT. In addition, the single string with VIT design eliminated instabilities in operational parameters (e.g. pressure) observed in the case of dual string. However, the single string with VIT case indicated that the heating rate of cement between the intermediate and surface casing string is the highest.