bluuebunny/crossref_metadata_2025_split huggingface dataset:
Algoritma K-Means Clustering Untuk Melakukan Segmentasi Pelanggan Di Toko Gbee Glow Beauty Bumirejo
Authors: Ismanto Bambang , Aisyah Siti , Darmawan Wachid 
Published: January 2025

Toko Gbee Glow Beauty Bumirejo merupakan toko yang menjual berbagai macam produk perawatan kulit wajah. Toko ini terletak di Jalan Pelita II No. 24 Bumirejo, Kota Pekalongan. Ada masalah dalam mengidentifikasi calon pelanggan dengan benar di Toko Gbee Glow Beauty Bumirejo. Segmentasi pelanggan dapat dilakukan menggunakan data mining dengan metode cluster untuk mengetahui potensi serta karakteristik dari setiap pelanggan. Dalam penelitian ini, metode yang digunakan adalah menggabungkan model Recency, Frekuensi, Moneter (RFM) dan algoritma k-means clustering yang digunakan untuk segmentasi pelanggan. Pembentukan cluster pelanggan didasarkan pada model RFM dan algoritma k-mean yang tepat menggunakan metode CRISP-DM. Dari penelitian yang ada di hasilkan 3 cluster pelanggan, cluster pertama berjumlah 2 pelanggan masuk dalam kategori highest loyalty, cluster kedua terdapat 13 pelanggan yang masuk dalam kategori low loyalty dan cluster ketiga berjumlah 5 pelanggan pada kategori medium loyalty. Untuk penelitian selanjutnya perlu melakukan perbandingan antara algoritma k-means dengan algoritma lainnya seperti k-medoids. Perbandingan tersebut digunakan untuk mengevaluasi hasil dari masing-masing algoritma dalam segmentasi pelanggan
Numerical Analysis of Three-Dimensional Fracture Propagation and Proppant Transport in Heterogeneous In-Situ Stress Reservoirs
Authors: Yang Peng , Zhang Shicheng , Zou Yushi 
Published: January 2025

ABSTRACT:
A fully coupled fracturing model of wellbore-perforation-fracture is proposed, considering key physical behaviors, such as the dynamic proppant-laden slurry distribution at each cluster, perforation erosion, nonplanar 3D fracture propagation, and proppant transport within fractures. The accuracy of the non-planar 3D fracture model is validated using the laboratory results from true triaxial hydraulic fracturing experiments. Numerical simulation results show that due to the solid-fluid density difference, proppant transport in the wellbore is affected by the particle slip effect, resulting in different proppant turning efficiencies among perforation clusters. For the given simulation parameters, the proppant concentration distribution in the wellbore presents a toe bias. In heterogeneous in-situ stress reservoirs, multiple fractures propagate in non-uniform and non-planar geometries. The uniformity of multi-fracture propagation is significantly influenced by the heterogeneous inter-cluster stress distribution, as the middle cluster fractures situated in high-stress regions struggle to initiate effectively. In-situ stress deviation promotes non-planar propagation and the intersection of hydraulic fractures. A larger deviation angle of the in-situ stress causes fractures to deviate and merge earlier, thereby limiting the propagation area of most fractures. Reducing the proppant particle size or increasing injection concentration can enhance the propped fracture area, which is particularly beneficial for fractures in reservoirs with smaller in-situ stress deviation angles.

1. INTRODUCTION
Multi-stage and multi-cluster fracturing technology for horizontal wells is currently the most effective method for stimulating unconventional oil and gas reservoirs (Miskimins, 2020). By conducting multi-cluster perforation and hydraulic fracturing within the designated stages, multiple fractures can be created simultaneously to maximize the stimulated reservoir volume (Ciezobka, 2021; Yang et al., 2023; Zou et al., 2022). Although multiple hydraulic fractures initiate and propagate simultaneously, their geometries and sizes are challenging to control with precision. Fracturing monitoring results in the field indicate that there is competitive propagation among multiple fractures, and the fracture morphologies are influenced by various factors, including rock mechanical properties, in-situ stress distribution, natural fractures, and pumping parameters (Ugueto et al., 2021).
Impact of Formation Heterogeneity on Efficiency of Hole Enlargement While Drilling (HEWD) Operations
Authors: Peter B. , Thiago M. , Syazwan M. S. M , Romulo A. , Giuseppe R. S. C. 
Published: January 2025

ABSTRACT:
The search for new oil and gas reserves has taken Operators to ultra-deepwater regions with water depths exceeding 3000m. This requires deeper wells and complex lithology, which necessitates multiple casing sizes and subsequently, hole enlargement operations. Hole enlargement poses challenges to the drilling operation such as low rates of penetration, vibration resulting in damage to the drilling assembly, and wellbore stability. The durability, stability, and drilling efficiency of the drillstring, drill bit and underreamer blocks are essential to delivering a project on time and on budget. Using a standard drilling assembly commonly used in the region as a base, an advanced 4D (3D + time) finite element transient drillstring dynamics modeling package was used to improve the cutting structures, and drilling dynamics, between different drilling assembly configurations. A detailed post-drill analysis is presented for the stability, reliability/robustness, and measurement quality with respect to the different formations encountered. This work resulted in the implementation of an improved, fully digital bit design and drillstring workflow that is formation-specific, integrating calibrated 4D dynamic simulation model, service provider and oil company experience to reduce risks when enlarging challenging post-salt formations in Brazil.

1. INTRODUCTION
Drilling can be described as the process of making hole in the ground by means of a surface drive, downhole drive, or a combination of both. Drilling is essential to extracting and unlocking the potential of underground resources such as Oil & Gas. However, Oil & Gas resources become scarcer, they become less accessible, resulting in more complicated drilling (Ultra-deepwater, hard formations, high pressure, high temperature, extended reach wells etc.). The complicated nature of these wells results in more casing strings and the need to enlarge the hole while drilling. Hole enlargement while drilling (HEWD) is the process of using a reamer above the bit to enlarge the pilot hole drilled by the bit. HEWD is primarily used to enlarge the hole below a casing shoe to a size equal to or larger than the previous casing OD or to drill a pilot hole with a small diameter required for logging while drilling. This has pushed operators and service providers to improve the speed and length of which a bottom hole assembly (BHA) drills, also known as drilling efficiency.
Pore Pressure Prediction Model Based on XGBOOST: A Case Study of Complex Geological Strata in Block K
Authors: Hu Naikun , Han Beiyu , Long Tengda , Tan Qiang , Deng Jingen , Liu Wei , Feng Yongcun , Li Xiaorong , Yang Heng , Shang Guanyi , Wang Yingxue 
Published: January 2025

ABSTRACT:
Pore pressure stands as a pivotal element in ensuring wellbore stability and is instrumental in shaping the design of drilling fluids, safety protocols, drilling speed, and cost efficiency in the realm of oil and gas exploration and production. Traditional pore pressure prediction methods, including the Eaton method, equivalent depth method, and empirical coefficient method, often introduce notable uncertainties and biases due to challenges in accurately determining the in-situ stress coefficient, limited neighboring well data, and applicability across different formations. The intricate interplay of lithology and irregular faulting patterns further contributes to non-uniform distributions of pore pressure within reservoirs, complicating assessments using simplistic mechanistic formulas. However, recent strides in machine learning and data analytics have spurred the development of hybrid models that combine contemporary computational techniques with conventional methods, leading to substantial advancements in evaluating pore pressure within complex geological settings. This study showcases a groundbreaking model that integrates geological and logging data with a Shapley value-based interpreter to enhance prediction accuracy and the interpretability of engineering parameters. The results unequivocally demonstrate that the XGB model surpasses other methods in predictive performance and stability, with Shapley values offering invaluable insights into pressure variations.

1. INTRODUCTION
Pore pressure is a crucial determinant in evaluating the stability of wellbore during drilling activities, impacting various operational aspects including drilling fluid design and safety protocols, as well as influencing mechanical drilling efficiency and cost management (Bourgoyne et al.,1986; Fan et al., 2015). The integrity of these predictions directly affects hydrocarbon exploration and the associated production processes. Traditional approaches to estimating pore pressure include methods such as the Eaton, equivalent depth, and empirical coefficient methods. However, these techniques often encounter significant challenges due to difficulties in obtaining continuous data regarding in-situ stress conditions, coupled with the limitations posed by seismic data resolution and the variability of rock mechanics parameters derived from well log interpretations and theoretical models (Lai et al., 2023). Such factors contribute to inconsistencies in the results produced by these theoretical models. Furthermore, the inherent lithological diversity and geological complexity further complicate the accurate forecasting of pore pressure distributions and variations (Li, 2024).
Numerical Analysis on Fracture Propagation Behavior of Radial Wellbore Cross-Layer Fracturing Based on 3D Discrete Lattice Method
Authors: Long Tengda , Yang Rui , Peng Sanli , Huang Zhongwei , Wu Xiaoguang , Xie Zixiao , Zou Wenchao , Sun Zhaowei , Sun Yaoyao , Hu Naikun , Shen Yazhou , Lu Meiquan , Wang Xiaohua 
Published: January 2025

ABSTRACT:
Radial wellbore fracturing, as an innovative technology for guiding fracture propagation, show great potential in improving fracture height and enhancing vertical stimulation performance, especially in multi-lithologic superimposed reservoirs. To determine the cross-layer propagation behaviors of fractures by radial wellbore fracturing in sand-shale interlayered rock mass, a numerical simulation study was conducted by employing a 3D discrete lattice method. By comparing with conventional horizontal well fracturing, the characteristic of fracture initiation and propagation of radial wellbore fracturing was illuminated, and the effect of layer combination sequence and radial wellbore dimension on fracture height was analyzed. The results indicate that the fracture has more significant cross-layer ability in radial wellbore fracturing, as compared to horizontal well fracturing, which could inhibit the fluid leakage between lithologic interfaces and increase the average fracture height by 75%. There is a positive correlation between fracture height and radial borehole length. Greater radial borehole length benefits increasing fracture height and activating more target shale layers, shifting the fracture morphology from arresting pattern to cross-layer pattern and skip-layer pattern. Regards to the lithologic layer sequence, setting the root end of radial borehole in high-strength sandstone layer is more conducive to achieving cross-layer propagation and improving fracture height, instead of setting in low-strength shale layer. These findings are expected to offer new insights and theoretical foundations for enhancing interlayered connectivity and stimulated reservoir volume in multi-layered formations.

1. INTRODUCTION
Horizontal wellbore fracturing technology is widely used in unconventional hydrocarbon resources production to improve oil-gas flow and reservoir permeability (Chen al., 2019; Hu al., 2020; Lin al., 2018). However, these reservoirs, such as shale oil, coalbed methane, tight oil, etc., generally develop high strength and high dense barrier-layer structures (Cheng al., 2012; Fu al., 2023). This limits the longitudinal extension of hydraulic fracture (HF), which is not conducive to the activation of lateral layers, and reduces the volume reconstruction range of the reservoir. Increasing the HF height is the key to promote the development of multi-lithologic superimposed reservoir (Wu al., 2024; Zhang al., 2023).
AI-Integrated Geology-Engineering Workflow for Hydraulic Fracture Evaluation and Production Prediction
Authors: Zeng Bo , Huang Haoyong , Chen Liqing , Liu Chuxi , Yu Wei , Leines Joseph , Miao Jijun 
Published: January 2025

ABSTRACT:
The increasing development of unconventional shale gas reservoirs necessitates more efficient and accurate methods for hydraulic fracture evaluation and reservoir production forecasting. This study introduces an AI-integrated geology-engineering workflow to optimize fracture geometry and production performance using GPU-based supercomputing. The workflow centers around the ZFRAC hydraulic fracture simulator, which employs the boundary element method (BEM) for fracture modeling and integrates XGBoost for calibration with pumping pressure data. A deep shale gas well in the Sichuan Basin, China, was modeled using detailed geomechanical parameters and 28 hydraulic fracturing stages. The fracture geometry was calibrated to reflect the actual reservoir conditions, achieving a 90% accuracy. The calibrated fractures were incorporated into the Embedded Discrete Fracture Model (EDFM) for production simulation and forecasting. The Estimated Ultimate Recovery (EUR) was predicted to be 0.163 billion cubic meters (bcm) over 20 years. The economic evaluation yielded a Net Present Value (NPV) of 27.4 million Chinese Yuan and an Internal Rate of Return (IRR) of +1.96% after 20 years. These results highlight the effectiveness of the workflow in optimizing fracture design and predicting long-term reservoir performance, offering valuable insights for future shale gas developments.

1. INTRODUCTION
In recent years, the development of unconventional oil and gas reservoirs has accelerated, driven by growing energy demand and advancements in extraction technologies. Shale gas reservoirs, particularly in the Sichuan Basin of southwestern China, have become a focal point due to their vast resource potential. The Sichuan Basin is one of the world's most prolific shale gas regions, with significant reserves trapped in tight formations that require enhanced stimulation techniques for optimal extraction (Yong et al., 2019; Zeng et al., 2021; Wu et al., 2023, 2024). Hydraulic fracturing is the primary method used to unlock these resources, but with the increasing number of wells and multi-pad developments, comprehensive evaluation of the fracturing process is essential. These assessments are critical for ensuring optimal performance, maximizing resource recovery, and minimizing operational inefficiencies.
Machine Learning-Based Prediction of Natural Fractures and Vugs in Carbonate Reservoir
Authors: Pang Huiwen , Wang Hanqing , Jin Yan , Tian Jingwei 
Published: January 2025

ABSTRACT:
To mitigate drilling risks and optimize the economic and efficient utilization of carbonate resources, precise reservoir characterization is essential. However, predicting the distribution of natural fractures and vugs in carbonate reservoirs using seismic and well data is fraught with uncertainty. This arises from challenges such as inadequate well interpretation, poor seismic imaging, and inconsistencies between well and seismic data. This study aims to reduce these uncertainties by calibrating the interpretation of natural fractures and vugs using well log and seismic data. Additionally, a machine learning model is developed to predict the 3D spatial distribution of fractures and vugs in limestone reservoirs. The research focuses on the limestone formations of the H oilfield in the southeastern Mesopotamia Basin of Iraq. Seismic attributes are extracted from inter-well regions based on well locations and tracks from six characteristic wells, and these attributes are classified and calibrated in relation to fractures and vugs. Data balancing techniques are applied, and feature engineering is performed to optimize model performance. An ensemble learning method is then used to establish a nonlinear mapping between the predicted targets (fractures, vugs, matrix) and seismic attributes. Blind well testing is conducted to verify the reliability of the model. The study ultimately provides a 3D prediction of the spatial distribution of fractures and vugs, derived from the established relationships rather than the original properties. The model achieves an average prediction accuracy of 83%. The results show that vugs are primarily distributed in the MA layer, while fractures and vugs are mainly found in the MB layer, and fractures are predominantly located in the MC layer. When planning horizontal wells, the well trajectory should be optimized to reduce the risks of mud loss and wellbore instability, particularly in the MC layer. The model offers detailed information on the distribution of fractures and vugs at different depths and geographical locations, providing crucial guidance for the development of optimal drilling plans and offering both technical and theoretical support for reservoir development strategies.
Four-Dimensional Ultrasonic Caliper While Drilling Enables Advanced Wellbore Evaluation in Slim Hole Size
Authors: Soelem R. , Taher A. , Fouda M. 
Published: January 2025

ABSTRACT:
Evaluation of hole conditions is a key measurement for safe drilling and completion operations. Acquiring an accurate hole size measurement has been traditionally performed using wireline mechanical calipers deployed after drilling operations have been completed. This paper demonstrates how logging-while-drilling (LWD) ultrasonic sensors can be used to provide a time-lapse (4D) alternative azimuthal measurement of hole size, enabling data acquisition in different phases of drilling and tripping operations.
LWD ultrasonic caliper measures the travel time and computes the tool's stand-off to the wellbore wall. Acquiring azimuthal data around the wellbore during different logging passes enables acquisition of 4D caliper information. After being calibrated inside casing, the ultrasonic sensor provides azimuthal travel-time images, based on which minimum, maximum, and average hole sizes can be computed.
Data have been acquired in drilling, trip-in, and trip-out modes and compared to wireline-oriented calipers. The data has been evaluated considering time-dependent deterioration, washout, and breakout developments.
Recently introduced LWD slim ultrasonic imaging and caliper tools have multiple transducers and fast sampling rates. The hardware and algorithm design improves the hole size computation and wellbore evaluation. The tools provide a viable alternative to wireline mechanical calipers. While field data showed a good match in competent formations, differences between data acquired in multiple LWD logging passes and wireline mechanical caliper runs have provided 4D caliper information for evaluating time-dependent changes in hole conditions enabling future optimization of well construction.
This paper illustrates the utilization of LWD ultrasonic sensors integrated as part of the drilling assembly to provide a 4D azimuthal measurement of hole size at different times, during drilling and tripping in and out of the hole.

Introduction
Maintaining stable and competent wellbores is essential for safe and successful drilling, logging, and completion of oil and gas wells. Wellbore instabilities can also cause unplanned operational delays and unnecessary costs. Well instability can also increase with an increase in well inclination, leading to higher costs in high-angle well operations. which may negate the benefit of horizontal drilling techniques (Aadony and Looyeh, 2010).
Predictions of Swab/Surge Pressure of Tripping Under Pump Circulation Based on Narrow Slot Geometry
Authors: Tan Zhenlai , Li Xiongrong , Wei Yaoran , Yan Shuang , Yang Tianyu , Feng Yongcun , Wang Guangyu 
Published: January 2025

ABSTRACT:
Swab/Surge pressure will increase the risk of wellbore stability such as lost circulation, wellbore collapse, kicks, and even blowouts, particularly in formations with narrow safe mud weight windows. The existing studies for predicting swab/surge pressures only consider pressure variations induced by tripping and hardly consider the effects of pump circulation during tripping. This paper presents a new steady-state model based on narrow slot geometry. The model aims to predict swab/surge pressure during tripping with pump circulation. Meanwhile, to mitigate the impact of fluctuation pressures on wellbore stability, the design of tripping speed, and pump displacement are investigated in this study. Results show pump circulation increases the pressure in the wellbore, partly offsetting swab pressure and increasing surge pressure. The faster the speed of tripping, the higher the fluctuation pressure. This study provides a theoretical foundation for predicting swab/surge pressure, which is of significant practical importance and application value in reducing wellbore instability caused by fluctuation pressure.

1. INTRODUCTION
In deep and ultra-deep drilling, accurately predicting pressure variations in the wellbore is crucial, especially in formation with a narrow safe mud weight windows (Cayeux and Daireaux, 2017; SUN et al., 2024; Wei et al., 2024). Tripping, casing and cementing can generate pressure variations (Balanza et al., 2015). Pressure variations caused by tripping are referred to as fluctuation pressures, which include swab pressure and surge pressure. Swab pressure, which is usually defined as a negative value, reduces the pressure in the wellbore (Mohammad and Davidrajuh, 2022; Meng et al., 2019). Figure 1, excessive swab pressure lowers the wellbore pressure to an unbalanced state, increasing the risk of wellbore collapse. Formation fluids enter the wellbore, potentially leading to a kick and eventually a blowout (Huang et al., 2022; Wei et al., 2022). Conversely, surge pressure, which is usually defined as a positive value, increases the pressure in the wellbore that may be in an overbalanced state. Figure 2, excessive surge pressure can lead to formation fractures or continuous leakage of drilling fluid into the permeable formation, ultimately resulting in lost circulation. Fluctuation pressure is a cause of wellbore instability (Cao et al., 2014; Zhao et al., 2023; Fekete et al., 2015). Therefore, accurate prediction of fluctuation pressure is essential for safe and efficient drilling (He et al., 2016; Ettehadi and Altun, 2018; Erge et al., 2018).