A Play-Wide Performance Review of Plug and Perf, Ball and Seat, and Pinpoint Fracturing Methods in the Montney Tight Siltstone Reservoir

2022 ◽  
Author(s):  
Benyamin Yadali Jamaloei ◽  
Robert Burstall ◽  
Amit Nakhwa
Keyword(s):  
Small Sample Size ◽  
Development Planning ◽  
Small Sample ◽  
Water Phase ◽  
Well Performance ◽  
Reservoir Properties ◽  
Clustering Technique ◽  
Casing Deformation ◽  
The Impact ◽  
Lateral Length

Abstract The Montney reservoir is one of the most prolific unconventional multi-stacked dry and liquid-rich gas plays in North America. The type of fracturing method and fluid has a significant impact on water-phase trapping, casing deformation, and well performance in the Montney. Different fracturing methods (plug and perf/plug and perf with ball/ball and seat/single-entry pinpoint) and fluids (slickwater/hybrid/oil-based/energized/foam) have been tested in 4000+ Montney wells to find optimal fracturing method and fluid for different reservoir qualities and fluid windows and to minimize water-phase trapping and casing deformation. The previous studies reviewing the performance of fracturing methods in Montney do not represent a holistic evaluation of these methods, due to some limitations, including: (1) Using a small sample size, (2) Having a limited scope by focusing on a specific aspect of fracturing (method/fluid), (3) Relying on data analytics approaches that offer limited subsurface insight, and (4) Generating misleading results (e.g., on optimum fracturing method/fluid) through using disparate data that are unstructured and untrustworthy due to significant regional variation in true vertical depth (TVD), geological properties, fluid windows, completed lateral length, fracturing method/fluid/date, and drawdown rate management strategy. The present study eliminates these limitations by rigorously clustering the 4000+ Montney wells based on the TVD, geological properties, fluid window, completed lateral length, fracturing method/fluid/date, and drawdown strategy. This clustering technique allows for isolating the effect of each fracturing method by comparing each well's production (normalized by proppant tonnage, fluid volume, and completed length) to that of its offsets that use different fracturing methods but possess similar geology and fluid window. With similar TVD and fracturing fluid/date, wells completed with pinpoint fracturing outperform their offsets completed with ball and seat and plug and perf fracturing. However, wells completed with ball and seat and plug and perf methods that outperform their offset pinpoint wells have either: (1) Been fractured 1 to 4 years earlier than pinpoint wells and/or (2) Used energized oil-based fluid, hybrid fluid, and energized slickwater versus slickwater used in pinpoint offsets, suggesting that the water-phase trapping is more severe in these pinpoint wells due to the use of slickwater. Previous studies often favored one specific fracturing method or fluid without highlighting these complex interplays between the type of fracturing method/fluid, completion date (regional depletion), and the reservoir properties and hydrodynamics. This clustering technique shows how proper data structuring in disparate datasets containing thousands of wells with significant variations in geological properties, fluid windows, fracturing method/fluid, regional depletion, and drawdown strategy permits a consistent well performance comparison across a play by isolating the impact of any given parameter (e.g., fracturing methods, depletion) that is deemed more crucial to fracturing design and field development planning.

scholarly journals A review of plug-and-perforate, ball-and-seat, and single-entry pinpoint fracturing performance in the unconventional montney reservoir

2021 ◽  
Vol 11 (3) ◽  
pp. 1155-1183
Author(s):  
Benyamin Yadali Jamaloei
Keyword(s):  
Small Sample Size ◽  
Specific Aspect ◽  
Small Sample ◽  
Fracturing Fluid ◽  
Reservoir Properties ◽  
Single Entry ◽  
Completion Date ◽  
Hybrid Fluid ◽  
Limited Scope ◽  
Lateral Length

AbstractThe Montney tight siltstone reservoir is a multi-stacked play, which covers a total area of 130,000 km2 along the Alberta–British Columbia border in Western Canada. Since the late 1990s, different fracturing methods and fluids have been tested in 4000-plus Montney wells to find the optimal fracturing method and fluid. The previous studies reviewing the performance of fracturing methods in Montney do not represent a holistic evaluation of these methods, owing to some limitations, including: (1) using a small sample size, (2) having a limited scope by focusing on a specific aspect of fracturing (method/fluid), (3) relying on data analytics approaches that offer limited subsurface insight, and (4) generating misleading results (e.g., on optimum fracturing method/fluid) through using disparate data that are unstructured and untrustworthy as a result of significant regional variations in true vertical depth (TVD), geological properties, fluid windows, completed lateral length, fracturing method/fluid/date, and drawdown rate management and choke size strategy. The present study eliminates these limitations by rigorously clustering 4000-plus Montney wells based on the TVD, fluid window, completed lateral length, fracturing method/fluid/date, and drawdown rate strategy to isolate the effect of each fracturing method by comparing each well’s production to that of its offsets, which use different fracturing methods but possess similar geology, fluid window, and TVD. With similar TVD, fracturing fluid, and completion date, wells completed with pinpoint fracturing method outperform their offsets completed with ball-and-seat and plug-and-perforate (PnP) fracturing methods. However, wells completed with ball-and-seat and PnP methods that outperform their offset pinpoint wells have either: (1) been fractured one to four years earlier than the pinpoint wells and/or (2) used energized oil-based fluid, hybrid fluid, and energized slickwater versus slickwater used in the pinpoint offsets. This suggests that the water-phase trapping is more severe in these pinpoint wells attributable to the use of slickwater. Previous studies often favored one specific fracturing method or fluid without highlighting these complex interplays between the type of fracturing method, fracturing fluid, completion date (regional depletion or well vintage), and the reservoir properties and hydrodynamics.

An influence of social isolation on the level of physical activity as well as on well-being and mental state of people during the coronavirus COVID-19 pandemic

2019 ◽  
Vol 129 (4) ◽  
pp. 127-131
Author(s):  
Agnieszka Parfin ◽  
Krystian Wdowiak ◽  
Marzena Furtak-Niczyporuk ◽  
Jolanta Herda
Keyword(s):  
Physical Activity ◽  
Social Isolation ◽  
Small Sample Size ◽  
Statistical Tests ◽  
Population Group ◽  
Well Being ◽  
Small Sample ◽  
Subjective Well Being ◽  
Tract Infections ◽  
The Impact

AbstractIntroduction. The COVID-19 is the name of an infectious disease caused by a new strain of coronavirus SARS-CoV-2 (Severe Acute Respiratory Syndrome Coronavirus 2). It was first diagnosed in December 2019 in patients in Wuhan City, Hubei Province, China. The symptoms are dominated by features of respiratory tract infections, in some patients with a very severe course leading to respiratory failure and, in extreme cases to death. Due to the spread of the infection worldwide, the WHO declared a pandemic in March 2020.Aim. An investigation of the impact of social isolation introduced due to the coronavirus pandemic on selected aspects of life. The researchers focused on observing changes in habits related to physical activity and their connections with people’s subjective well-being and emotional state.Material and methods. The study was carried out within the international project of the group „IRG on COVID and exercise”. The research tool was a standardized questionnaire.Results. Based on the data collected and the analysis of the percentage results, it can be observed that the overwhelming majority of people taking up physical activity reported a better mood during the pandemic. However, statistical tests do not confirm these relationships due to the small sample size.Conclusions. Isolation favours physical activity. Future, in-depth studies, by enlarging the population group, are necessary to confirm the above observations.

scholarly journals The Role of Dopamine Receptor D2 in Bridging the Intention-Behavior Gap in Sport Participation

2021 ◽  
Vol 18 (5) ◽  
pp. 2379
Author(s):  
Seiyeong Park ◽  
Junhye Kwon ◽  
Chiyoung Ahn ◽  
Hae-Sung Cho ◽  
Hyo Youl Moon ◽  
...  
Keyword(s):  
University Students ◽  
Dopamine Receptor ◽  
Sport Participation ◽  
Small Sample Size ◽  
Behavioral Model ◽  
Small Sample ◽  
Male Students ◽  
Future Research ◽  
Dopamine Receptor D2 ◽  
The Impact

Previous studies have identified that a behavior can occur through the strongest predictor intention, but there is a gap between intention and behavior. Dopamine receptor D2 (DRD2) is known to account for a variance in sporting behaviors in human and animal subjects. However, the relationship between DRD2 and sport participation has been poorly studied, and the limited available reports are inconsistent. The present study was performed to examine the impact of DRD2 on sport participation among Korean university students based on the integrated behavioral model (IBM). Data were collected from enrolled university students in Seoul (N = 45). Participants answered survey questions first, and then they gave investigators their hair to provide DNA information (i.e., the A1 allele of DRD2). DRD2 had a significant effect on sport participation, but only in male students. Male students who carried the A1 allele of DRD2 significantly participated in 105.10 min more sporting activities than male students who did not. Moreover, the effect of intention on sport participation was significantly decreased when considering DRD2. Despite the small sample size, the results of this study could be a preliminary case for a larger study and indicate the direction of future research. Our results suggest that DRD2 may have played an important role as the “actual skill” shown in the IBM.

Nipple Confusion

PEDIATRICS ◽  
1993 ◽  
Vol 92 (2) ◽  
pp. 300-301
Author(s):  
DOREN FREDRICKSON
Keyword(s):  
Breast Feeding ◽  
Statistical Power ◽  
White Women ◽  
Small Sample Size ◽  
False Negative ◽  
Small Sample ◽  
Bottle Feeding ◽  
Feeding Duration ◽  
Breast Feed ◽  
The Impact

To the Editor.— I wish to comment on the study reported by Cronenwett et al,1 which was a fascinating prospective study among married white women who planned to breast-feed. Women were randomly selected to perform either exdusive breast-feeding or partial breast-feeding with bottled human milk supplements to determine the impact of infant temperament and limited bottle-feeding on breast-feeding duration. The authors admit that small sample size and lack of statistical power make a false-negative possible.

The impact of vestibular symptoms and electronystagmography results on recovery from sudden sensorineural hearing loss

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Gaelle Vofo ◽  
Marrigje Aagje de Jong ◽  
Michal Kaufman ◽  
Julia Meyler ◽  
Ron Eliashar ◽  
...  
Keyword(s):  
Hearing Loss ◽  
Sensorineural Hearing Loss ◽  
Small Sample Size ◽  
Small Sample ◽  
Sudden Sensorineural Hearing Loss ◽  
Sensorineural Hearing ◽  
Caloric Test ◽  
Routine Identification ◽  
The Impact ◽  
Caloric Tests

Abstract Objectives Idiopathic sudden sensorineural hearing loss (SSNHL) represents a frequently encountered otological entity, of various types and severity, with an array of associated symptoms including vertigo. This is a devastating life-changing condition with a blurry prognosis. The objective of this study was to determine the clinical association of vestibular impairment by electronystagmography (ENG) and caloric tests, and their ability to predict prognosis. Methods An observational, crossectional study was carried out amongst patients admitted with SSNHL. Each consenting patient had an audiometry test performed on admission as well as ENG and caloric tests. Treatment included oral steroids and carbogen with intratympanic steroids used only as salvage treatment. Follow-up was completed after 6 months when hearing gains were evaluated. Finally, an association was sought between the rate of recovery and ENG and caloric test results. Results Of 35 patients included, marked recovery was seen in patients without vertigo when compared to those with vertigo (p=0.003). A statistically significant association was found between the presence of vertigo and hearing deterioration (p=0.008). More so, normal electronystagmography results were associated with marked recovery (p=0.04). Conclusions The vestibular end organs are both subjectively and objectively affected in SSNHL as demonstrated by the abnormal ENG and caloric tests in our study despite the small sample size. Concomitant vestibular involvement carries poorer prognosis and routine identification may help foresee the recovery of patients with SSNHL and as such, aid in patient counseling. ENG and caloric tests are easily available and may be recommended for all patients with SSNHL.

CEOs’ accounting-based attributes and earnings management strategies under mandatory IFRS adoption

2018 ◽  
Vol 19 (4) ◽  
pp. 608-625 ◽  
Author(s):  
Amel Kouaib ◽  
Anis Jarboui ◽  
Khaireddine Mouakhar
Keyword(s):  
Earnings Management ◽  
Small Sample Size ◽  
Small Sample ◽  
Moderating Effect ◽  
Audit Committees ◽  
Content Type ◽  
Ifrs Adoption ◽  
Experience Education ◽  
The Impact ◽  
The Relationship

Purpose The purpose of this paper is to focus on the moderating effect of mandatory International Financial Reporting Standards (IFRS) adoption on the relationship between chief executive officer (CEO) experience/education and earnings management in European companies. Design/methodology/approach Data from a sample of 302 European firms listed on Stoxx Europe 600 index and 596 CEOs from 2000 to 2014 are used to test the moderation model using moderation regression analysis. Findings Evidence reveals that CEO’s accounting-based attributes are negatively associated with accruals-based earnings management and positively associated with real earnings management (REM). Further, mandatory IFRS adoption significantly moderates the impact of CEO’s accounting-based traits on earnings-management activities. Research limitations/implications A small number of European firms were studied and, given the long study period, many firms with missing data were eliminated. To avoid a small sample size, countries with few observations were included, which leads to an uneven distribution between observations per country. Practical implications Findings from this paper can help: European firms to consider demographic traits when recruiting or promoting executives; the IASB to improve enforcement mechanisms and make IFRS implementation mandatory; and audit committees to effectively monitor REM. Originality/value This study is unique in providing European evidence for the moderating effect of mandatory IFRS adoption on the relationship between CEOs’ accounting experience/education and earnings management activities. This paper is also relevant as it addresses the effectiveness and efficiency of accounting literates.

scholarly journals Congenital Micropenis: Aetiology And Management

2021 ◽  
Author(s):  
Marianna Rita Stancampiano ◽  
Kentaro Suzuki ◽  
Stuart O’Toole ◽  
Gianni Russo ◽  
Gen Yamada ◽  
...  
Keyword(s):  
Racial Differences ◽  
Small Sample Size ◽  
Small Sample ◽  
Long Term Outcomes ◽  
Penile Length ◽  
Appearance Quality ◽  
Wide Range ◽  
The Impact

Abstract In the newborn, penile length is determined by a number of androgen dependent and independent factors. The current literature suggests that there are inter-racial differences in stretched penile length in the newborn and although congenital micropenis should be defined as a stretched penile length of less than 2.5SDS of the mean for the corresponding population and gestation, a pragmatic approach would be to evaluate all boys with a stretched penile length below 2 cm, as congenital micropenis can be a marker for a wide range of endocrine conditions. However, it remains unclear as to whether the state of micropenis, itself, is associated with any long-term consequences. There is a lack of systematic studies comparing the impact of different therapeutic options on long-term outcomes, in terms of genital appearance, quality of life and sexual satisfaction. To date, research has been hampered by a small sample size and inclusion of a wide range of heterogeneous diagnoses; for these reasons, condition specific outcomes have been difficult to compare between studies. Lastly, there is a need for a greater collaborative effort in collecting standardized data so that all real-world or experimental interventions performed at an early age can be studied systematically into adulthood.

scholarly journals The impact of visual impairment on nutritional status: A systematic review

2018 ◽  
Vol 36 (1) ◽  
pp. 17-30 ◽  
Author(s):  
Nabila Jones ◽  
Hannah Bartlett
Keyword(s):  
Nutritional Status ◽  
Visual Impairment ◽  
Sample Size ◽  
Visually Impaired ◽  
Small Sample Size ◽  
Small Sample ◽  
Control Group ◽  
Visually Impaired People ◽  
Impaired People ◽  
The Impact

The aim of this review was to evaluate the literature that has investigated the impact of visual impairment on nutritional status. We identified relevant articles through a multi-staged systematic approach. Fourteen articles were identified as meeting the inclusion criteria. The sample size of the studies ranged from 9 to 761 participants. It was found that visual impairment significantly affects nutritional status. The studies reported that visually impaired people have an abnormal body mass index (BMI); a higher prevalence of obesity and malnutrition was reported. Visually impaired people find it difficult to shop for, eat, and prepare meals. Most studies had a small sample size, and some studies did not include a study control group for comparison. The limitations of these studies suggest that the findings are not conclusive enough to hold true for only those who are visually impaired. Further studies with a larger sample size are required with the aim of developing interventions.

Impact of race on biomarker testing among HER2- advanced breast cancer (ABC) patients (pts) in the United States: Results from a real-world study.

2021 ◽  
Vol 39 (15_suppl) ◽  
pp. 10598-10598
Author(s):  
Reshma L. Mahtani ◽  
Alexander Niyazov ◽  
Katie Lewis ◽  
Lucy Massey ◽  
Alex Rider ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Targeted Therapies ◽  
Small Sample Size ◽  
The United States ◽  
Small Sample ◽  
Access To Treatment ◽  
History Of ◽  
Biomarker Testing ◽  
Abstract Data ◽  
The Impact

10598 Background: African Americans (AA) have the highest breast cancer (BC) mortality rate. Access to treatment is a known contributing factor. In the past 4 years, several targeted therapies for HER2- BC have become available which require testing for specific biomarkers. This study assessed the impact of race on biomarker testing rates in HER2- ABC pts receiving treatment in the US. Methods: Oncologists were recruited to abstract data from medical charts for the next 8-10 pts receiving treatment with HER2- ABC during Sept 2019-Apr 2020. Pts records were stratified by race and categorized into 3 mutually exclusive cohorts [White/Caucasian (White), AA, Other]. The other race cohort was excluded from this analysis due to small sample size. Differences in pt demographics/clinical characteristics were analyzed via Fisher’s exact tests. Testing rates for actionable biomarkers (i.e. BRCA1/2, PIK3CA, PD-L1) were compared between White and AA pts utilizing logistic regressions controlling for age, known family history of a BRCA-related cancer, hormone receptor (HR) status and practice setting (academic vs. community). Further analyses by age will be presented. Results: This analysis included 378 pts records, provided by 40 oncologists. Mean age was 64 years; 77% had HR+/HER2- ABC; 20% had advanced triple negative breast cancer (TNBC), 3% had ABC with an unknown HR status. Compared to White pts, AA pts were significantly more likely to have advanced TNBC (27% vs. 18%, p<0.05). Compared to White pts, AA pts had significantly lower BRCA1/2 mutation (mut) testing rates (Table). Numerically lower rates of PIK3CAmut and PD-L1 testing were observed among AA pts (Table). BRCA1/2mut positivity rate (germline [g] and/or somatic [s]) was higher among AA vs. White pts (30% vs. 22%). Positivity rate for PIK3CAmut was lower for AA vs. White pts (8% vs. 11%). Conclusions: A higher than expected BRCA1/2mut positivity rate was observed than previously reported in the literature. This is likely because this analysis included s BRCA1/2mut and represented a high risk pt population. Across all biomarkers assessed, AA pts had lower testing rates than White pts. This suggests racial disparities in testing rates of actionable biomarkers. Consistent with guidelines, and with the increased availability of targeted therapies, focused efforts should be developed to increase biomarker testing in AA pts. Funding: Pfizer Biomarker Testing Rates by Race.[Table: see text]

scholarly journals Rectified Wing Loss for Efficient and Robust Facial Landmark Localisation with Convolutional Neural Networks

2019 ◽  
Vol 128 (8-9) ◽  
pp. 2126-2145 ◽  
Author(s):  
Zhen-Hua Feng ◽  
Josef Kittler ◽  
Muhammad Awais ◽  
Xiao-Jun Wu
Keyword(s):  
Neural Networks ◽  
Convolutional Neural Networks ◽  
Loss Function ◽  
Data Augmentation ◽  
Small Sample Size ◽  
Small Sample ◽  
Imbalance Problem ◽  
Facial Landmark ◽  
The Impact ◽  
Coarse To Fine

AbstractEfficient and robust facial landmark localisation is crucial for the deployment of real-time face analysis systems. This paper presents a new loss function, namely Rectified Wing (RWing) loss, for regression-based facial landmark localisation with Convolutional Neural Networks (CNNs). We first systemically analyse different loss functions, including L2, L1 and smooth L1. The analysis suggests that the training of a network should pay more attention to small-medium errors. Motivated by this finding, we design a piece-wise loss that amplifies the impact of the samples with small-medium errors. Besides, we rectify the loss function for very small errors to mitigate the impact of inaccuracy of manual annotation. The use of our RWing loss boosts the performance significantly for regression-based CNNs in facial landmarking, especially for lightweight network architectures. To address the problem of under-representation of samples with large pose variations, we propose a simple but effective boosting strategy, referred to as pose-based data balancing. In particular, we deal with the data imbalance problem by duplicating the minority training samples and perturbing them by injecting random image rotation, bounding box translation and other data augmentation strategies. Last, the proposed approach is extended to create a coarse-to-fine framework for robust and efficient landmark localisation. Moreover, the proposed coarse-to-fine framework is able to deal with the small sample size problem effectively. The experimental results obtained on several well-known benchmarking datasets demonstrate the merits of our RWing loss and prove the superiority of the proposed method over the state-of-the-art approaches.

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