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Enhancing production monitoring: A back allocation methodology to estimate well flow rates and assist well test scheduling

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PETROLEUm RESEARCH 2024年第3期9卷 369-379页

作者： Chaves, G. S. Ferreira Filho, V. j. m. Univ Fed Rio De j.neiro Rio De Janeiro Brazil

Production flow rates are crucial to make operational decisions, monitor, manage, and optimize oil and gas fields. Flow rates also have a financial importance to correctly allocate production to fiscal purposes required by regulatory agencies or to allocate production in fields owned by multiple operators. Despite its significance, usually only the total field production is measured in real time, which requires an alternative way to estimate wells' production. To address these challenges, this work presents a back allocation methodology that leverages real-time instrumentation, simulations, algorithms, and mathematical programming modeling to enhance well monitoring and assist in well test scheduling. The methodology comprises four modules: simulation, classification, error calculation, and optimization. These modules work together to characterize the flowline, wellbore, and reservoir, verify simulation outputs, minimize errors, and calculate flow rates while honoring the total platform flow rate. The well status generated through the classification module provides valuable information about the current condition of each well (i.e. if the well is deviating from the latest well test parameters), aiding in decision-making for well testing scheduling and prioritizing. The effectiveness of the methodology is demonstrated through its application to a representative offshore oil field with 14 producing wells and two years of daily production data. The results highlight the robustness of the methodology in properly classifying the wells and obtaining flow rates that honor the total platform flow rate. Furthermore, the methodology supports well test scheduling and provides reliable indicators for well conditions. By utilizing real-time data and advanced modeling techniques, this methodology enhances production monitoring and facilitates informed operational decision-making in the oil and gas industry. (c) 2024 The Authors. Publishing services provided by Elsevier B.V. on be

关键词： Production estimation Real-time production Production monitoring Back allocation Well test scheduling Flow rate estimation 2-PHASE FLOW

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Revised in-depth meta-analysis on the efficacy of robot-assisted versus traditional free-hand pedicle screw insertion

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Laparoscopic, Endoscopic, and Robotic Surgery 2024年第4期7卷 155-165页

作者： Chumnanvej.S. Pillai B.m. Suthakorn j. Neurosurgery Division Department of Surgery Faculty of Medicine Ramathibodi Hospital Mahidol University Bangkok Thailand Department of Anesthesiology and Operating Room Phramongkutklao Hospital Bangkok Thailand Center for Biomedical and Robotics Technology (BART LAB) Faculty of Engineering Mahidol University Bangkok Thailand

Obj.ctive: Robot-assisted pedicle screw insertion has recently emerged as an alternative to the traditional free-hand technique. However, discrepancies in the accuracy of screw placement between the 2 methods have been highlighted by some comparative studies. This meta-analysis was conducted to synthesize evidence comparing these techniques. methods: Searches were conducted in 5 electronic databases adhering to specific eligibility criteria for randomized and observational studies. The data were analyzed using Revman software and the results are presented as odds ratios (ORs), mean differences, or standard mean differences (SmDs) with 95% confidence intervals (CIs). Our analysis included 12 studies (7 randomized trials and 5 observational studies, involving 883 patients and 4903 screws). Results: The results demonstrated a higher rate of Grade A Gertzbein and Robbins pedicle placement score (OR: 1.77; 95% CI: 1.10–2.87), a lower rate of revision surgeries (OR: 0.21; 95% CI: 0.09–0.52), and a shorter radiation exposure duration (SmD = −1.38, 95% CI: −2.32 to −0.44) in the robot-assisted group compared with the free-hand group. Nonetheless, the length of hospital stay, volume of intraoperative blood loss, postoperative visual analogue scale scores for back pain, and rate of wound infection were similar between the 2 groups. Significant heterogeneity was observed in some outcomes. Conclusion: Compared with the free-hand method, the robot-assisted technique provides greater accuracy and reduced radiation exposure. The efficacy of the robot-assisted technique is expected to improve further as experience with its use in surgery grows. © 2024 Zhej.ang University

关键词： Fluoroscopy Free-hand meta-analysis Pedicle screw placement Robotic surgery

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Frequency-dependent viscoelasticity effects on the wave attenuation performance of multi-layered periodic foundations

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Applied mathematics and mechanics(English Edition) 2024年第3期45卷 407-424页

作者： m.SAFI m.VAKILIFARD m.j.mAHmOODI Faculty of Civil Water&Environmental EngineeringShahid Beheshti UniversityTehran ***Iran Faculty of mechanical and Energy Engineering Shahid Beheshti UniversityTehran ***Iran

In this paper,layered periodic foundations(LPFs)are numerically examined for their responses to longitudinal and transverse modes in the time and frequency *** different unit-cells,i.e.,2-layer,4-layer,and 6-layer unit-cells,comprising concrete/rubber,concrete/rubber/steel/rubber,and concrete/rubber/steel/rubber/lead/rubber materials,respectively,are taken into ***,the viscoelasticity behavior of the rubber is modeled with two factors,i.e.,a frequency-independent(FI)loss factor and a linear frequency-dependent(FD)loss *** the extraction of the complex dispersion curves and the identification of the band gaps(BGs),the simulations of wave transmission in the time and frequency domains are performed using the COmSOL *** parametric studies evaluate the effects of the rubber viscoelasticity models on the dispersion curves and the wave transmission for the longitudinal and transverse *** results show that considering the rubber viscoelasticity enhances the wave attenuation ***,the transverse-mode damping is more sensitive to the viscoelasticity model than its longitudinal *** 6-layer unit-cell LPF exhibits the lowest BG,ranging from 4.8 Hz to 6.5 Hz.

关键词： layered metamaterial periodic foundation complex dispersion curve wave transmission diagram

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A comparison of laparoscopic to open pancreaticoduodenectomy for pancreatic adenocarcinoma by propensity score matching analysis

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Laparoscopic, Endoscopic, and Robotic Surgery 2024年第4期7卷 141-146页

作者： m.unt j. m.unt B. Poruk K. Tice m. Stauffer j.A. Department of Surgery Mayo Clinic Jacksonville FL United States medical Education Heritage College of Osteopathic Medicine Ohio University Athens OH United States medical Education The University of Toledo College of Medicine and Life Sciences Toledo OH United States

Obj.ctive: In previous studies, laparoscopic pancreaticoduodenectomy (LPD) has demonstrated safety and potential benefits over open pancreaticoduodenectomy (OPD) for pancreatic adenocarcinoma (PDAC). After performing both LPD and OPD procedures interchangeably in routine practice for a decade, the outcomes of LPD versus OPD for PDAC were analyzed and compared at a single institution. Our primary aim was to compare features of LPD and OPD in PDAC patients so that the suitable surgical approach may be chosen for each individual. methods: From j.nuary 2010 through December 2020, all patients undergoing pancreaticoduodenectomy (PD) were identified, and information was collected prospectively. At a single institution, PD was performed on 589 patients, of whom 347 were OPD patients and 242 were LPD patients. After excluding those who underwent pancreatectomy for indications other than PDAC, total pancreatectomy, maj.r vascular or concomitant organ resection, there were 237 patients (OPD = 157, LPD = 80). Then propensity score matching was completed to analyze 77 OPD patients versus 77 LPD patients to create a similar group of patients who underwent either LPD or OPD for PDAC. A comparison of perioperative data and 90-day outcomes with subsequent statistical analysis was performed. Results: Operative time (491 min vs. 281 min, p mptying (15.6% vs. 3.9%, p = 0.027) were higher for LPD than OPD respectively but overall morbidity was similar. Blood loss, mortality and post-pancreatectomy hemorrhage were also similar for both groups, but total costs ($60,245 vs. $50,900, p = 0.002) were significantly higher for LPD than OPD. Recurrence and overall survival were similar for the two groups. Conclusion: In our experience, LPD does not offer any advantages over OPD for PDAC and is associated with a higher rate of complications and costs. © 2024 Zhej.ang University

关键词： Laparoscopy Pancreatic ductal adenocarcinoma Pancreatic fistula Pancreaticoduodenectomy Whipple

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Selection of digital fabrication technique in the construction industry--A multi-criteria decision-making approach

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Frontiers of Structural and Civil Engineering 2024年第7期18卷 977-997页

作者： m.P.SALAImANImAGUDAm j.j.YAPRAKASH Department of Structural and Geotechnical Engineering School of Civil EngineeringVellore Institute of TechnologyVellore 632014India

Digital fabrication techniques,in recent decades,have provided the basis of a sustainable revolution in the construction ***,selecting the digital fabrication method in terms of manufacturability and functionality requirements is a complex *** paper presents alternatives and criteria for selection of digital fabrication techniques by adopting the multi-criteria decision-making *** alternatives considered in the study are concrete three-dimensional(3D)printing,shotcrete,smart dynamic casting,material intrusion,mesh molding,inj.ction concrete 3D printing,and thin forming *** criteria include formwork utilization,reinforcement incorporation,geometrical complexity,material enhancement,assembly complexity,surface finish,and build *** demonstrates different multi-criteria decision-making techniques,with both subj.ctive and obj.ctive weighting *** given ranking is based on the current condition of digital fabrication in the construction *** study reveals that in the selection of digital fabrication techniques,the criteria including reinforcement incorporation,build area,and geometrical complexity play a pivotal role,collectively accounting for nearly 70% of the overall *** the evaluated techniques,concrete 3D printing emerged as the best performer,however the shotcrete and mesh molding techniques in the second and third positions.

关键词： digital fabrication multicriteria decision-making concrete 3D printing

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Lattice Boltzmann method formulation for simulation of thermal radiation effects on non-Newtonian Al_(2)O_(3) free convection in entropy determination

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Applied mathematics and mechanics(English Edition) 2024年第6期45卷 1085-1106页

作者： m.NEmATI m.SEFID A.KARImIPOUR A.j.CHAmKHA Faculty of mechanical Engineering Yazd UniversityYazd ***Iran Department of mechanical Engineering Najafabad BranchIslamic Azad UniversityNajafabad ***Iran Faculty of Engineering Kuwait College of Science and TechnologyDoha 35004Kuwait

The simultaneous investigation on the parameters affecting the flow of electrically conductive fluids such as volumetric radiation,heat absorption,heat generation,and magnetic field(mF)is very vital due to its existence in various sectors of industry and *** present research focuses on mathematical modeling to simulate the cooling of a hot component through power-law(PL)nanofluid convection *** temperature reduction of the hot component inside a two-dimensional(2D)inclined chamber with two different cold wall shapes is *** formulation of the problem is derived with the lattice Boltzmann method(LBm)by code writing via the FORTRAN *** variables such as the radiation parameter(0–1),the Hartmann number(0–75),the heat absorption/generation coefficient(−5–5),the fluid behavioral index(0.8–1.2),the Rayleigh number(103–105),the imposed mF angle(0°–90°),the chamber inclination angle(−90°–90°),and the cavity cold wall shape(smooth and curved)are *** findings indicate that the presence of radiation increases the mean Nusselt number value for the shear-thickening,Newtonian,and shear thinning fluids by about 6.2%,4%,and 2%,*** most cases,the presence of nanoparticles improves the heat transfer(HT)rate,especially in the cases where thermal conduction dominates *** is the lowest cooling performance index and mF effect for the cavity placed at an angle of 90°.The application in the design of electronic coolers and solar collectors is one of the practical cases of this numerical research.

关键词： thermal performance analysis heat absorption/generation power-law(PL)Al_(2)O_(3)nanofluid magnetohydrodynamics natural convection volumetric radiation inclined cavity

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Consumer transparency in the production chain for plant varieties produced using new genomic techniques

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aBIOTECH 2024年第2期5卷 239-246页

作者： j.m.Lukasiewicz C.C.m.van de Wiel L.A.P.Lotz m.j.m.Smulders Wageningen University&Research P.O.Box 386NL-6700 AJ WageningenThe Netherlands

Plants edited with new genomic techniques(NGTs)currently fall under the Genetically modified Organisms Directive(2001/18/EC)in the European *** the proposal of the European Commission,NGT plants are partially exempted from the regulations of this *** proposal makes a distinction between two categories of NGT plants:NGT-1 and ***-1 category plants are considered equal to plants obtained through conventional breeding *** plants will not be labelled for the consumer,although they will be labelled as ***-2 category plants may be labelled with additional information as a positive *** of seeds of varieties made with gene editing,but not the products,would mean that most steps in the production chain are transparent,but not the last step towards ***“right to know”and increasing knowledge of gene-edited food is a common theme in food labelling towards ***,we describe current labelling regimes and registers and how these may be applied to provide transparency on gene-edited products to ***,we also look into consumer studies,which indicate a greater acceptance of gene-edited food among consumers,especially when additional benefits such as sustainability are mentioned.

关键词： Labelling New genomic techniques Consumer transparency Plant products

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message Verification Protocol Based on Bilinear Pairings and Elliptic Curves for Enhanced Security in Vehicular Ad Hoc Networks

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Computers, materials and Continua 2024年第1期81卷 1029-1057页

作者： Nyangaresi V.O. Ghaib A.A. j.sim H.m. Abdulj.bbar Z.A. ma j. Al Sibahee m.A. Aldarwish A.j.Y. Ali A.H. Neamah H.A. Department of Computer Science and Software Engineering Jaramogi Oginga Odinga University of Science and Technology Bondo 40601 Kenya Department of Applied Electronics Saveetha School of Engineering SIMATS Tamilnadu Chennai 602105 India Information Technology Department Management Technical College Southern Technical University Basrah 61004 Iraq Department of Computer Science College of Education for Pure Sciences University of Basrah Basrah 61004 Iraq College of Big Data and Internet Shenzhen Technology University Shenzhen 518118 China Huazhong University of Science and Technology Shenzhen Institute Shenzhen 518000 China National Engineering Laboratory for Big Data System Computing Technology Shenzhen University Shenzhen 518060 China Computer Technology Engineering Department Iraq University College Basrah 61004 Iraq Department of mathematics College of Education for Pure Sciences University of Basrah Basrah 61004 Iraq Institute of mathematics University of Debrecen Debrecen H-4002 Hungary Department of Electrical Engineering and mechatronics Faculty of Engineering University of Debrecen Debrecen 4028 Hungary

Vehicular ad hoc networks (VANETs) provide intelligent navigation and efficient route management, resulting in time savings and cost reductions in the transportation sector. However, the exchange of beacons and messages over public channels among vehicles and roadside units renders these networks vulnerable to numerous attacks and privacy violations. To address these challenges, several privacy and security preservation protocols based on blockchain and public key cryptography have been proposed recently. However, most of these schemes are limited by a long execution time and massive communication costs, which make them inefficient for on-board units (OBUs).Additionally, some of them are still susceptible tomany *** such, this study presents a novel protocol based on the fusion of elliptic curve cryptography (ECC) and bilinear pairing (BP) operations. The formal security analysis is accomplished using the Burrows-Abadi-Needham(BAN) logic, demonstrating that our scheme is verifiably secure. The proposed scheme's informal security assessment also shows that it provides salient security features, such as non-repudiation, anonymity, and unlinkability. moreover, the scheme is shown to be resilient against attacks, such as packet replays, forgeries,message falsifications, and impersonations. Fromthe performance perspective, this protocol yields a 37.88% reduction in communication overheads and a 44.44% improvement in the supported security features. Therefore, the proposed scheme can be deployed in VANETs to provide robust security at low overheads. © 2024 The Authors. Published by Tech Science Press.

关键词： Attacks bilinear elliptic curve cryptography (ECC) privacy security vehicular ad hoc network (VANET)

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Sports Events Recognition Using multi Features and Deep Belief Network

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Computers, materials and Continua 2024年第1期81卷 309-326页

作者： Alabdullah B. Tayyab m. AlQahtani Y. mudawi N.A. Algarni A. j.lal A. Park j. Department of Information Systems College of Computer and Information Sciences Princess Nourah bint Abdulrahman University P.O. Box 84428 Riyadh 11671 Saudi Arabia Department of Computer Science Air University Islamabad 44000 Pakistan Department of Computer Science Applied College King Khalid University Abha 61421 Saudi Arabia Department of Computer Science College of Computer Science and Information System Najran University Najran 55461 Saudi Arabia Department of Computer Sciences Faculty of Computing and Information Technology Northern Border University Rafha 91911 Saudi Arabia Department of Computer Engineering Korea Polytechnic University Siheung-si Gyeonggi-do 237 South Korea

In the modern era of a growing population, it is arduous for humans to monitor every aspect of sports, events occurring around us, and scenarios or conditions. This recognition of different types of sports and events has increasingly incorporated the use of machine learning and artificial intelligence. This research focuses on detecting and recognizing events in sequential photos characterized by several factors, including the size, location, and position of people’s body parts in those pictures, and the influence around those people. Common approaches utilized, here are feature descriptors such as mSER (maximally Stable Extremal Regions), SIFT (Scale-Invariant Feature Transform), and DOF (degree of freedom) between the j.int points are applied to the skeleton points. moreover, for the same purposes, other features such as BRISK (Binary Robust Invariant Scalable Keypoints), ORB (Oriented FAST and Rotated BRIEF), and HOG (Histogram of Oriented Gradients) are applied on full body or silhouettes. The integration of these techniques increases the discriminative nature of characteristics retrieved in the identification process of the event, hence improving the efficiency and reliability of the entire procedure. These extracted features are passed to the early fusion and DBscan for feature fusion and optimization. Then deep belief, network is employed for recognition. Experimental results demonstrate a separate experiment’s detection average recognition rate of 87% in the HmDB51 video database and 89% in the YouTube database, showing a better perspective than the current methods in sports and event identification. © 2024 The Authors. Published by Tech Science Press.

关键词： extremal regions j.int points machine learning scalable keypoints silhouettes

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A Facial Expression Recognition method Integrating Uncertainty Estimation and Active Learning

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Computers, materials and Continua 2024年第1期81卷 533-548页

作者： Wang Y. Zhang j. Sun R. School of Computer Science and Engineering Chongqing University of Technology Chongqing 400054 China Data Space Research Institute of Hefei Comprehensive National Science Center Hefei 230088 China

The effectiveness of facial expression recognition (FER) algorithms hinges on the model’s quality and the availability of a substantial am.unt of labeled expression data. However, labeling large datasets demands significant human, time, and financial resources. Although active learning methods have mitigated the dependency on extensive labeled data, a cold-start problem persists in small to medium-sized expression recognition datasets. This issue arises because the initial labeled data often fails to represent the full spectrum of facial expression characteristics. This paper introduces an active learning approach that integrates uncertainty estimation, aiming to improve the precision of facial expression recognition regardless of dataset scale variations. The method is divided into two primary phases. First, the model undergoes self-supervised pre-training using contrastive learning and uncertainty estimation to bolster its feature extraction capabilities. Second, the model is fine-tuned using the prior knowledge obtained from the pre-training phase to significantly improve recognition accuracy. In the pre-training phase, the model employs contrastive learning to extract fundamental feature representations from the complete unlabeled dataset. These features are then weighted through a self-attention mechanism with rank regularization. Subsequently, data from the low-weighted set is relabeled to further refine the model’s feature extraction ability. The pre-trained model is then utilized in active learning to select and label information-rich samples more efficiently. Experimental results demonstrate that the proposed method significantly outperforms existing approaches, achieving an improvement in recognition accuracy of 5.09% and 3.82% over the best existing active learning methods, margin, and Least Confidence methods, respectively, and a 1.61% improvement compared to the conventional segmented active learning method. © 2024 The Authors.

关键词： active learning Expression recognition self-supervised learning uncertainty estimation

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