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Improved Harris Hawks Algorithm and Its Application in Feature Selection

Computers, Materials and Continua 2024年第1期81卷 1251-1273页

作者： Zhang Q. Li Y. Zhan j. Chen S. School of Computer Science and Information Engineering Harbin Normal University Harbin 150025 China College of Systems Engineering National University of Defense Technology Changsha 410073 China

This research focuses on improving the Harris' Hawks Optimization algorithm (HHO) by tackling several of its shortcomings, including insufficient population diversity, an imbalance in exploration vs. exploitation, and a lack of thorough exploitation depth. To tackle these shortcomings, it proposes enhancements from three distinct perspectives: an initialization technique for populations grounded in opposition-based learning, a strategy for updating escape energy factors to improve the equilibrium between exploitation and exploration, and a comprehensive exploitation approach that utilizes variable neighborhood search along with mutation operators. The effectiveness of the Improved Harris Hawks Optimization algorithm (IHHO) is assessed by comparing it to five leading algorithms across 23 benchmark test functions. Experimental findings indicate that the IHHO surpasses several contemporary algorithms its problem-solving capabilities. Additionally, this paper introduces a feature selection method leveraging the IHHOalgorithm(IHHO-FS) to address challenges such as lowefficiency in feature selection and high computational costs (time to find the optimal feature combination and model response time) associated with high-dimensional datasets. Comparative analyses between IHHO-FS and six other advanced feature selection methods are conducted across eight datasets. The results demonstrate that IHHO-FS significantly reduces the computational costs associated with classification models by lowering data dimensionality, while also enhancing the efficiency of feature selection. Furthermore, IHHO-FS shows strong competitiveness relative to numerous algorithms. © 2024 The Authors. Published by Tech Science Press.

关键词： deep exploitation strategy energy factor update strategy feature selection HHO IHHO population diversity

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Paraelectric Doping Simultaneously Improves the Field Frequency Adaptability and Dielectric Properties of Ferroelectric Materials: A Phase-Field Study

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Computers, Materials and Continua 2024年第1期81卷 213-228页

作者： Wang Z. Cao j. Liu Z. Zhao Y. School of Materials Science and Engineering Collaborative Innovation Center of Ministry of Education and Shanxi Province for High-Performance Al/Mg Alloy Materials North University of China Taiyuan 030051 China Beij.ng Advanced Innovation Center for Materials Genome Engineering University of Science and Technology Beijing Beijing 100083 China Institute of Materials Intelligent Technology Liaoning Academy of Materials Shenyang 110004 China

Recent years, the polarization response of ferroelectrics has been entirely studied. However, it is found that the polarization may disappear gradually with the continually applied of electric field. In this paper, taking K0.48Na0.52NbO3(KNN) as an example, it was demonstrated that the residual polarization began to decrease when the electric field frequency increased to a certain extent using a phase-field methods. The results showed that the content of out-of-plane domains increased first and then decreased with the increase of applied electric field frequency, the maximum polarization disappeared at high frequencies, and the hysteresis loop became elliptical. In order to further study the abnormal changes of hysteresis loops of ferroelectrics under high electric field frequency, we analyzed the hysteresis loop and dielectric response of solid solution 0.1SrTiO3-0.9K0.48Na0.52NbO3. It was found that the doped hysteresis loop maintained its shape at higher frequency and the dielectric constant increased. This kind of doping has a higher field frequency adaptability, which has a key guiding role in improving the dielectric properties of ferroelectric thin films and expanding the frequency application range of ferroelectric nano memory. © 2024 The Authors. Published by Tech Science Press.

关键词： dielectric properties doping electric field frequency Ferroelectric ceramics phase field method

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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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Error field penetration in j.TEXT tokamak based on two-fluid drift-MHD model

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Chinese Physics B 2024年第4期33卷 545-551页

作者：王文徐涛张仪 the j.TEXT team State Key Laboratory of Advanced Electromagnetic Technology International Joint Research Laboratory of Magnetic Confinement Fusion and Plasma PhysicsSchool of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074China

An externally generated resonant magnetic perturbation can induce complex non-ideal MHD responses in their resonant *** have studied the plasma responses using Fitzpatrick's improved two-fluid model and program *** calculated the error field penetration threshold for *** addition,we find that the island width increases slightly as the error field amplitude increases when the error field amplitude is below the critical penetration ***,the island width suddenly j.mps to a large value because the shielding effect of the plasma against the error field disappears after the *** scanning the natural mode frequency,we find that the shielding effect of the plasma decreases as the natural mode frequency ***,we obtain the m/n=2/1 penetration threshold scaling on density and temperature.

关键词： plasma responses drift-MHD model error field penetration

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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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Small universal simple spiking neural P systems with weights

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Science China(Information Sciences) 2014年第9期57卷 19-29页

作者： ZENG XiangXiang PAN LinQiang PREZ-jim.nez Mario j. Key Laboratory of Image Processing and Intelligent Control School of AutomationHuazhong University of Science and Technology Department of Computer Science and Artificial Intelligence University of SevillaAvda. Reina Mercedes s/nSevilla 41012Spain

Spiking neural P systems with weights(WSN P systems,for short)are a new variant of spiking neural P systems,where the rules of a neuron are enabled when the potential of that neuron equals a given *** is known that WSN P systems are universal by simulating register ***,in these universal systems,no bound is considered on the number of neurons and *** this work,a restricted variant of WSN P systems is considered,called simple WSN P systems,where each neuron has only one *** complexity parameter,the number of neurons,to construct a universal simple WSN P system is *** is proved that there is a universal simple WSN P system with 48 neurons for computing functions;as generator of sets of numbers,there is an almost simple(that is,each neuron has only one rule except that one neuron has two rules)and universal WSN P system with 45 neurons.

关键词： bio-inspired computing membrane computing P system spiking neural P system universal computing device

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Efficient User Identity Linkage Based on Aligned Multimodal Features and Temporal Correlation

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Computers, Materials and Continua 2024年第1期81卷 251-270页

作者： Gao j. Zheng K. Wang X. Wu C. Wu B. School of Cyberspace Security Beijing University of Posts and Telecommunications Beijing 100876 China Faculty of Information Technology Beijing University of Technology Beijing 100124 China

User identity linkage (UIL) refers to identifying user accounts belonging to the same identity across different social media platforms. Most of the current research is based on text analysis, which fails to fully explore the rich image resources generated by users, and the existing attempts touch on the multimodal domain, but still face the challenge of semantic differences between text and images. Given this, we investigate the UIL task across different social media platforms based on multimodal user-generated contents (UGCs). We innovatively introduce the efficient user identity linkage via aligned multi-modal features and temporal correlation (EUIL) approach. The method first generates captions for user-posted images with the BLIP model, alleviating the problem of missing textual information. Subsequently, we extract aligned text and image features with the CLIP model, which closely aligns the two modalities and significantly reduces the semantic gap. Accordingly, we construct a set of adapter modules to integrate the multimodal features. Furthermore, we design a temporal weight assignment mechanism to incorporate the temporal dimension of user behavior. We evaluate the proposed scheme on the real-world social dataset TWIN, and the results show that our method reaches 86.39% accuracy, which demonstrates the excellence in handling multimodal data, and provides strong algorithmic support for UIL. © 2024 The Authors. Published by Tech Science Press.

关键词： attention mechanism multimodal models temporal correlation User identity linkage

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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： Mount j. Mount 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 j.ang University

关键词： Laparoscopy Pancreatic ductal adenocarcinoma Pancreatic fistula Pancreaticoduodenectomy Whipple

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Spiking neural P systems with neuron division and budding

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Science China(Information Sciences) 2011年第8期54卷 1596-1607页

作者： P■UN Gheorghe PREZ-jim.nez Mario j. Department of Computer Science and Artificial Intelligence University of Sevilla Avda Reina Mercedes s/n 41012 Sevilla Spain Institute of Mathematics of the Romanian Academy PO Box 1-764 014700 Bucuresti Romania

Spiking neural P systems are a class of distributed and parallel computing models inspired by spiking *** this work,the features of neuron division and neuron budding are introduced into the framework of spiking neural P systems,which are processes inspired by neural stem cell division. With neuron division and neuron budding,a spiking neural P system can generate exponential work space in polynomial time as the case for P systems with active *** this way,spiking neural P systems can efficiently solve computationally hard problems by means of a space-time tradeoff,which is illustrated with an efficient solution to SAT problem.

关键词： natural computing membrane computing spiking neural P system neuron division

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Evaluating the Effects of Graviton Redshift upon Spiral Galaxy Rotation Curves, Surface Brightness Magnitudes and Gravitational Lensing

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j.urnal of High Energy Physics, Gravitation and Cosmology 2024年第3期10卷 967-985页

作者： Firmin j. Oliveira East Asian Observatory James Clerk Maxwell Submillimetre Telescope Hilo USA

The effects of the gravitational redshift of gravitons upon spiral galaxy rotation energy are compared to the standard mass to light analyses in obtaining rotation curves. The derivation of the total baryonic matter compares well with the standard theory and the rotation velocity is matched to a high precision. The stellar mass distributions obtained from the fit with graviton energy loss are used to derive the surface brightness magnitudes for the galaxies, which agree well with the observed measurements. In a new field of investigation, the graviton theory is applied to the observations of gravitational lenses. The results of these applications of the theory suggest that it can augment the standard methods and may eliminate the need for dark matter.

关键词： Gravitons Gravitational Redshift Surface Brightness Gravitational Lens Lens Mass

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