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Advanced time complexity analysis for real-time COVID-19 prediction in Saudi Arabia using LightGBM and XGBoost

JOURNAL OF RADIATION RESEARCH AND APPLIED SCIENCES 2025年第2期18卷

作者： Sadig, Husam Eldin Kamal, Mustafa ur Rehman, Masood Habadi, Maryam Ibrahim Alnagar, Dalia Kamal Yusuf, M. Mohammed, Mohammed Omar Musa Alqasem, Ohud A. Meraou, M. A. Dhofar Univ Coll Arts & Appl Sci Dept Math & Sci Salalah Oman Saudi Elect Univ Coll Sci & Theoret Studies Dept Basic Sci Dammam 32256 Saudi Arabia Saudi Elect Univ Coll Comp & Informat Dept Informat Technol Dammam 32256 Saudi Arabia King Abdulaziz Univ Fac Sci Dept Stat Jeddah 21589 Saudi Arabia Univ Tabuk Fac Sci Dept Stat Tabuk Saudi Arabia Helwan Univ Fac Sci Dept Math Helwan Egypt Prince Sattam Bin Abdulaziz Univ Coll Business Adm Hotat Bani Tamim Dept Accounting Al Hulwah Saudi Arabia Princess Nourah Bint Abdulrahman Univ Coll Sci Dept Math Sci POB 84428 Riyadh 11671 Saudi Arabia Univ Djillali Liabes Sidi Bel Abbes Lab Stat & Stochast Proc BP 89 Sidi Bel 22000 Abbes Algeria

This study addresses the critical need for predictive models that balance high accuracy with computational efficiency, a requirement essential for timely and effective public health responses to COVID-19 outbreaks. We evaluate the performance of two advanced machine learning models, LightGBM and XGBoost, in predicting COVID-19 case trends across five Saudi cities. Using time-series data, we analyze key metrics such as RMSE, MAE, MAPE, R2, and computation time to assess each model's suitability for real-time applications. The findings highlight XGBoost's superior performance in computational speed, being up to three times faster than LightGBM in certain cases, making it ideal for rapid decision-making scenarios. Meanwhile, LightGBM demonstrates competitive accuracy and exceptional scalability, positioning it as a reliable tool for managing large datasets. These insights underscore the importance of time complexity as a critical factor in predictive modeling, enabling public health organizations to allocate resources efficiently, implement containment strategies promptly, and develop agile responses to future pandemics.

关键词： Machine learning XGBoost LightGBM COVID-19 Epidemiology time complexity analysis Statistical analysis

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A time AND SPACE complexity analysis OF MODEL INTEGRATION

A TIME AND SPACE COMPLEXITY ANALYSIS OF MODEL INTEGRATION

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Winter Simulation Conference

作者： North, Michael J. Argonne Natl Lab 9700 S Cass Ave Argonne IL 60439 USA

ISBN: (纸本)9781479974863

The computational study of complex systems increasingly requires model integration. The drivers include a growing interest in leveraging accepted legacy models, an intensifying pressure to reduce development costs by reusing models, and expanding user requirements that are best met by combining different modeling methods. There have been many published successes including supporting theory, conceptual frameworks, software tools, and case studies. Nonetheless, on an empirical basis, the published work suggests that correctly specifying model integration strategies remains challenging. This naturally raises a question that has not yet been answered in the literature, namely 'what is the computational difficulty of model integration?' This paper's contribution is to address this question with a time and space complexity analysis that concludes that deep model integration with proven correctness is both NP-complete and PSPACE-complete and that reducing this complexity requires sacrificing correctness proofs in favor of guidance from both subject matter experts and modeling specialists.

关键词： computational complexity data integration large-scale systems complex systems conceptual frameworks correctness proofs deep model integration software tools space complexity analysis supporting theory time complexity analysis user requirements Analytical models Clustering algorithms complexity theory Computational modeling Data models Mathematical model Software

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Efficiency evaluation of structural nonlinear analysis method based on the Woodbury formula

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ENGINEERING COMPUTATIONS 2019年第4期36卷 1082-1100页

作者： Li, Gang Jia, Shuo Li, Hong-Nan Dalian Univ Technol State Key Lab Coastal & Offshore Engn Dalian Peoples R China Shenyang Jianzhu Univ Sch Civil Engn Shenyang Liaoning Peoples R China

Purpose The purpose of this paper is to make a theoretical comprehensive efficiency evaluation of a nonlinear analysis method based on the Woodbury formula from the efficiency of the solution of linear equations in each incremental step and the selected iterative algorithms. Design/methodology/approach First, this study employs the time complexity theory to quantitatively compare the efficiency of the Woodbury formula and the LDLT factorization method which is a commonly used method to solve linear equations. Moreover, the performance of iterative algorithms also significantly effects the efficiency of the analysis. Thus, the three-point method with a convergence order of eight is employed to solve the equilibrium equations of the nonlinear analysis method based on the Woodbury formula, aiming to improve the iterative performance of the Newton-Raphson (N-R) method. Findings First, the result shows that the asymptotic time complexity of the Woodbury formula is much lower than that of the LDLT factorization method when the number of inelastic degrees of freedom (IDOFs) is much less than that of DOFs, indicating that the Woodbury formula is more efficient for local nonlinear problems. Moreover, the time complexity comparison of the N-R method and the three-point method indicates that the three-point method is more efficient than the N-R method for local nonlinear problems with large-scale structures or a larger ratio of IDOFs number to the DOFs number. Originality/value This study theoretically evaluates the efficiency of nonlinear analysis method based on the Woodbury formula, and quantitatively shows the application condition of the comparative methods. The comparison result provides a theoretical basis for the selection of algorithms for different nonlinear problems.

关键词： Newton-Raphson method Nonlinear analysis Three-point method time complexity analysis Woodbury formula

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PARALLEL ALGORITHMS FOR PLANAR DOMINANCE COUNTING

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PARALLEL COMPUTING 1990年第1-3期15卷 241-246页

作者： KIM, SK Department of Computer Science FR-35 University of Washington Seattle WA 98195 USA

Given n points in the plane the planar dominance counting problem is to determine for each point the number of points dominated by it. Point p is said to dominate point q if x(q)x(p) and y(q)y(p), when x(p) and y(p) are the x? and y-coordinate of p, respectively. We present two CREW PRAM parallel algorithms for the problem, one running in O(log n loglog n) time and and the other in O(lognloglogn/logloglogn) time both using O(n) processors. Some applicationsare also given.

关键词： Parallel algorithms Planar dominance counting time complexity analysis

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PARALLEL CLUSTERING ALGORITHMS

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PARALLEL COMPUTING 1989年第3期11卷 275-290页

作者： LI, X FANG, Z CONCURRENT COMP CORP RES & DEVTINTON FALLSNJ 07724

Clustering techniques play an important role in exploratory pattern analysis, unsupervised learning and image segmentation applications. Many clustering algorithms, both partitional clustering and hierarchical clustering, require intensive computation, even for a modest number of patterns. This paper presents two parallel clustering algorithms. For a clustering problem with N = 2n patterns and M = 2m features, the time complexity of the traditional partitional clustering algorithm on a single processor computer is O(MNK), where K is the number of clusters. The proposed algorithm on anSIMD computer with MN processors has a time complexity O(K(n + m)). The time complexity of the proposed single-link hierarchical clustering algorithm is reduced from O(MN2) of the uniprocessor algorithm to O(nN) with MN processors.

关键词： Clustering techniques pattern analysis parallel partitional clustering algorithm time complexity analysis hypercube

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New morphological methods to generate two-dimensional curve offsets

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INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY 2014年第9-12期71卷 1687-1700页

作者： Dolen, Melik Yaman, Ulas Middle E Tech Univ Dept Mech Engn TR-06800 Ankara Turkey

For the purpose of generating 2D curve offsets used in 2.5D machining, four new methods based on morphological operations on different mathematical entities are presented in this paper. All of the methods, which lend themselves for parallel processing, exploit the idea that the boundaries formed by a circular structuring element whose center sweeps across the points on a generator/base curve comprise the entire offsets of the progenitor. The first approach, which is a carry-over from image processing, makes good use of morphological operations on binary images to produce 2D offsets via contour tracing algorithms. The second method, which is to rectify the high memory cost associated with the former technique, utilizes morphological operations on (boundary data) sets. The implementation of this basic technique is illustrated by two Matlab functions given in the paper. Despite its simplicity, the time complexity of this paradigm is found to be high. Consequently, the third method, which is evolved from the preceding one, reduces the time complexity significantly with the utilization of a geometric range search method. This technique, which has a considerable margin for improvement, is found to be suitable to be used as a part of the real-time motion command generator for CNC applications. Unlike the previous schemes, the final approach uses polygon operations to generate such curves. The run-time of this technique is highly governed by the complexity of the polygon overlay algorithm selected. The paper analyzes the complexity of each technique. Finally, the presented methods are evaluated (in terms of run-time and geometric accuracy) via two test cases where most CAD/CAM packages fail to yield acceptable results.

关键词： Curve offset generation Morphological operations Boolean operation on polygons time complexity analysis

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Optimal union-find in Constraint Handling Rules

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THEORY AND PRACTICE OF LOGIC PROGRAMMING 2006年第1-2期6卷 213-224页

作者： Schrijvers, T Frühwirth, T Katholieke Univ Leuven Dept Comp Sci Louvain Belgium Univ Ulm Fac Comp Sci D-89069 Ulm Germany

Constraint Handling Rules (CHR) is a committed-choice rule-based language that was originally intended for writing constraint solvers. In this paper we show that it is also possible to write the classic union-find algorithm and variants in CHR. The programs neither compromise in declarativeness nor efficiency. We study the time complexity of our programs: they match the almost-linear complexity of the best known imperative implementations. This fact is illustrated with experimental results.

关键词： declarative algorithms time complexity analysis disjoint-set problem union-find algorithm constraint handling rules

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On the approximation ability of evolutionary optimization with application to minimum set cover

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ARTIFICIAL INTELLIGENCE 2012年 180卷 20-33页

作者： Yu, Yang Yao, Xin Zhou, Zhi-Hua Nanjing Univ Natl Key Lab Novel Software Technol Nanjing 210093 Jiangsu Peoples R China Univ Birmingham Sch Comp Sci Ctr Excellence Res Computat Intelligence & Applic Birmingham B15 2TT W Midlands England

Evolutionary algorithms (EAs) are heuristic algorithms inspired by natural evolution. They are often used to obtain satisficing solutions in practice. In this paper, we investigate a largely underexplored issue: the approximation performance of EAs in terms of how close the solution obtained is to an optimal solution. We study an EA framework named simple EA with isolated population (SEIP) that can be implemented as a single- or multi-objective EA. We analyze the approximation performance of SEIP using the partial ratio, which characterizes the approximation ratio that can be guaranteed. Specifically, we analyze SEIP using a set cover problem that is NP-hard. We find that in a simple configuration, SEIP efficiently achieves an H-n-approximation ratio, the asymptotic lower bound, for the unbounded set cover problem. We also find that SEIP efficiently achieves an (H-k - k-1/8k(9))- approximation ratio, the currently best-achievable result, for the k-set cover problem. Moreover, for an instance class of the k-set cover problem, we disclose how SEIP, using either one-bit or bit-wise mutation, can overcome the difficulty that limits the greedy algorithm. (C) 2012 Elsevier B.V. All rights reserved.

关键词： Evolutionary algorithms Approximation algorithm Approximation ratio k-Set cover time complexity analysis

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A gradient-based morphological method to produce planar curve offsets

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INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY 2015年第1-4期80卷 255-274页

作者： Yaman, Ulas Dolen, Melik Middle E Tech Univ Dept Mech Engn TR-06800 Ankara Turkey

Two-dimensional curve offsets have a wide application area ranging from manufacturing to medical imaging. To that end, this paper concentrates on two novel techniques to produce planar curve offsets. Both methods, which are based on mathematical morphology, employ the concept that the boundaries formed by a circular structuring element whose center moves across the points on a base curve comprise the entire offsets of the progenitor. The first technique titled IMOBS was introduced in our former paper and was shown to have superior properties in terms of its high accuracy, low computational complexity, and its ability to handle complex curves if compared to the techniques available in the literature. Consequently, an all-purpose algorithm titled AMOBS is introduced to enhance further the performance of the former technique by making good use of gradient information to find globally the most suitable candidate points in the boundary data set via grid search techniques. Thus, the new paradigm is demonstrated to overcome some of the problems (like orphan curve offsets) encountered in extreme cases. Both algorithms, which have similar attributes in terms of run-time complexity and memory cost, are comparatively tested via two experimental cases where most CAD/CAM packages fail to yield acceptable results.

关键词： Curve offset generation Morphological operations time complexity analysis Geometric accuracy Self-intersecting curves Grid search

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Analyzing time complexity of Practical Learned Image Compression Models

Analyzing Time Complexity of Practical Learned Image Compres...

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IEEE International Conference on Visual Communications and Image Processing (VCIP) - Visual Communications in the Era of AI and Limited Resources

作者： Pan, Xiaohan Guo, Zongyu Chen, Zhibo Univ Sci & Technol China CAS Key Lab Technol Geospatial Informat Proc & Ap Hefei Peoples R China

ISBN: (纸本)9781728185514

We have witnessed the rapid development of learned image compression (LIC). The latest LIC models have outperformed almost all traditional image compression standards in terms of rate-distortion (RD) performance. However, the time complexity of LIC model is still underdiscovered, limiting the practical applications in industry. Even with the acceleration of GPU, LIC models still struggle with long coding time, especially on the decoder side. In this paper, we analyze and test a few prevailing and representative LIC models, and compare their complexity with traditional codecs including H.265/HEVC intra and H.266/VVC intra. We provide a comprehensive analysis on every module in the LIC models, and investigate how bitrate changes affect coding time. We observe that the time complexity bottleneck mainly exists in entropy coding and context modelling. Although this paper pay more attention to experimental statistics, our analysis reveals some insights for further acceleration of LIC model, such as model modification for parallel computing, model pruning and a more parallel context model.

关键词： time complexity analysis Image Compression Parallel Computing Neural Networks

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