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A Theoretical Comparison among Recursive Algorithms for Fast Computation of Zernike Moments Using the Concept of Time Complexity
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作者 Nasrin Bastani Alireza Vard +1 位作者 Mehdi Jabalameli Vahid Bastani 《American Journal of Computational Mathematics》 2021年第4期304-326,共23页
Zernike polynomials have been used in different fields such as optics, astronomy, and digital image analysis for many years. To form these polynomials, Zernike moments are essential to be determined. One of the main i... Zernike polynomials have been used in different fields such as optics, astronomy, and digital image analysis for many years. To form these polynomials, Zernike moments are essential to be determined. One of the main issues in realizing the moments is using factorial terms in their equation which cause</span><span style="font-size:10.0pt;font-family:"">s</span><span style="font-size:10.0pt;font-family:""> higher time complexity. As a solution, several methods have been presented to reduce the time complexity of these polynomials in recent years. The purpose of this research is to study several methods among the most popular recursive methods for fast Zernike computation and compare them <span>together by a global theoretical evaluation system called worst-case time co</span><span>mplexity. In this study, we have analyzed the selected algorithms and calculate</span>d the worst-case time complexity for each one. After that, the results are represented and explained and finally, a conclusion has been made by comparing th</span><span style="font-size:10.0pt;font-family:"">ese</span><span style="font-size:10.0pt;font-family:""> criteria among the studied algorithms. According to time complexity, we have observed that although some algorithms </span><span style="font-size:10.0pt;font-family:"">such </span><span style="font-size:10.0pt;font-family:"">as Wee method and Modified Prata method were successful in having the smaller time complexit<span>ies, some other approaches did not make any significant difference compa</span>r</span><span style="font-size:10.0pt;font-family:"">ed</span><span style="font-size:10.0pt;font-family:""> to the classical algorithm. 展开更多
关键词 time complexity Uniform Model Zernike Moments Zernike Polynomi-als
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Motion and Special Relativity in Complex Spaces
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作者 Jerzy K. Filus 《Journal of Applied Mathematics and Physics》 2024年第1期330-361,共32页
A natural extension of the Lorentz transformation to its complex version was constructed together with a parallel extension of the Minkowski M<sup>4</sup> model for special relativity (SR) to complex C<... A natural extension of the Lorentz transformation to its complex version was constructed together with a parallel extension of the Minkowski M<sup>4</sup> model for special relativity (SR) to complex C<sup>4</sup> space-time. As the [signed] absolute values of complex coordinates of the underlying motion’s characterization in C<sup>4</sup> one obtains a Newtonian-like type of motion whereas as the real parts of the complex motion’s description and of the complex Lorentz transformation, all the SR theory as modeled by M<sup>4</sup> real space-time can be recovered. This means all the SR theory is preserved in the real subspace M<sup>4</sup> of the space-time C<sup>4</sup> while becoming simpler and clearer in the new complex model’s framework. Since velocities in the complex model can be determined geometrically, with no primary use of time, time turns out to be definable within the equivalent theory of the reduced complex C<sup>4</sup> model to the C<sup>3</sup> “para-space” model. That procedure allows us to separate time from the (para)space and consider all the SR theory as a theory of C<sup>3</sup> alone. On the other hand, the complex time defined within the C<sup>3</sup> theory is interpreted and modeled by the single separate C<sup>1</sup> complex plane. The possibility for application of the C<sup>3</sup> model to quantum mechanics is suggested. As such, the model C<sup>3</sup> seems to have unifying abilities for application to different physical theories. 展开更多
关键词 Special Relativity Complex Space and time Models and Dramatic SR Simplification Complex time and Space Separation Complex time Interpretation
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Modified Elliptic Curve Cryptography Multi-Signature Scheme to Enhance Security in Cryptocurrency 被引量:1
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作者 G.Uganya Radhika Baskar 《Computer Systems Science & Engineering》 SCIE EI 2023年第4期641-658,共18页
Internet of Things(IoT)is an emerging technology that moves the world in the direction of smart things.But,IoT security is the complex problem due to its centralized architecture,and limited capacity.So,blockchain tec... Internet of Things(IoT)is an emerging technology that moves the world in the direction of smart things.But,IoT security is the complex problem due to its centralized architecture,and limited capacity.So,blockchain technology has great attention due to its features of decentralized architecture,transparency,immutable records and cryptography hash functions when combining with IoT.Cryptography hash algorithms are very important in blockchain technology for secure transmission.It converts the variable size inputs to a fixed size hash output which is unchangeable.Existing cryptography hash algorithms with digital signature have issues of single node accessibility and accessed up to 128 bytes of key size only.As well as,if the attacker tries to hack the key,it cancels the transaction.This paper presents the Modified Elliptic Curve Cryptography Multi Signature Scheme(MECC-MSS)for multiple node accessibility by finding nearest path for secure transaction.In this work,the input key size can be extended up to 512 bytes to enhance the security.The performance of the proposed algorithm is analyzed with other cryptography hash algorithms like Secure Hashing Algorithms(SHAs)such as SHA224,SHA256,SHA384,SHA512,SHA3-224,SHA3-256,SHA3-384,SHA3-512 and Message Digest5 by one-way analysis of variance test in terms of accuracy and time complexity.Results show that the MECC-MSS achieves 90.85%of accuracy and time complexity of 1.4 nano seconds with significance less than 0.05.From the statistical analysis,it is observed that the proposed algorithm is significantly better than other cryptography hash algorithms and also having less time complexity. 展开更多
关键词 Internet of things blockchain technology secure hash algorithm ACCURACY time complexity
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Decreasing complexity of glucose time series derived from continuous glucose monitoring is correlated with deteriorating glucose regulation 被引量:1
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作者 Cheng Li Xiaojing Ma +7 位作者 Jingyi Lu Rui Tao Xia Yu Yifei Mo Wei Lu Yuqian Bao Jian Zhou Weiping Jia 《Frontiers of Medicine》 SCIE CSCD 2023年第1期68-74,共7页
Most information used to evaluate diabetic statuses is collected at a special time-point,such as taking fasting plasma glucose test and providing a limited view of individual’s health and disease risk.As a new parame... Most information used to evaluate diabetic statuses is collected at a special time-point,such as taking fasting plasma glucose test and providing a limited view of individual’s health and disease risk.As a new parameter for continuously evaluating personal clinical statuses,the newly developed technique“continuous glucose monitoring”(CGM)can characterize glucose dynamics.By calculating the complexity of glucose time series index(CGI)with refined composite multi-scale entropy analysis of the CGM data,the study showed for the first time that the complexity of glucose time series in subjects decreased gradually from normal glucose tolerance to impaired glucose regulation and then to type 2 diabetes(P for trend<0.01).Furthermore,CGI was significantly associated with various parameters such as insulin sensitivity/secretion(all P<0.01),and multiple linear stepwise regression showed that the disposition index,which reflectsβ-cell function after adjusting for insulin sensitivity,was the only independent factor correlated with CGI(P<0.01).Our findings indicate that the CGI derived from the CGM data may serve as a novel marker to evaluate glucose homeostasis. 展开更多
关键词 complexity of glucose time series continuous glucose monitoring impaired glucose regulation insulin secretion and sensitivity refined composite multi-scale entropy
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An efficiency algorithm on Gaussian mixture UKF for BDS/INS navigation system 被引量:6
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作者 Qing Dai Lifen Sui +2 位作者 Lingxuan Wang Tian Zeng Yuan Tian 《Geodesy and Geodynamics》 2018年第2期169-174,共6页
To further improve the performance of UKF(Unscented Kalman Filter) algorithm used in BDS/SINS(BeiDou Navigation Satellite System/Strap down Inertial Navigation System), an improved GM-UKF(Gaussian Mixture Unscented Ka... To further improve the performance of UKF(Unscented Kalman Filter) algorithm used in BDS/SINS(BeiDou Navigation Satellite System/Strap down Inertial Navigation System), an improved GM-UKF(Gaussian Mixture Unscented Kalman Filter) considering non-Gaussian distribution is discussed in this paper. This new algorithm using SVD(Singular Value Decomposition) is proposed to alternative covariance square root calculation in UKF sigma point production. And to end the rapidly increasing number of Gaussian distributions, PDF(Probability Density Function) re-approximation is conducted. In principle this efficiency algorithm proposed here can achieve higher computational speed compared with traditional GM-UKF. And simulation experiment result show that, compared with UKF and GM-UKF algorithm, new algorithm implemented in BDS/SINS tightly integrated navigation system is suitable for handling nonlinear/non-Gaussian integrated navigation position calculation, for its lower computational complexity with high accuracy. 展开更多
关键词 Gaussian mixture UKF Singular Value Decomposition Integrated navigation time complexity
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Smart Bubble Sort:A Novel and Dynamic Variant of Bubble Sort Algorithm
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作者 Mohammad Khalid Imam Rahmani 《Computers, Materials & Continua》 SCIE EI 2022年第6期4895-4913,共19页
In the present era,a very huge volume of data is being stored in online and offline databases.Enterprise houses,research,medical as well as healthcare organizations,and academic institutions store data in databases an... In the present era,a very huge volume of data is being stored in online and offline databases.Enterprise houses,research,medical as well as healthcare organizations,and academic institutions store data in databases and their subsequent retrievals are performed for further processing.Finding the required data from a given database within the minimum possible time is one of the key factors in achieving the best possible performance of any computer-based application.If the data is already sorted,finding or searching is comparatively faster.In real-life scenarios,the data collected from different sources may not be in sorted order.Sorting algorithms are required to arrange the data in some order in the least possible time.In this paper,I propose an intelligent approach towards designing a smart variant of the bubble sort algorithm.I call it Smart Bubble sort that exhibits dynamic footprint:The capability of adapting itself from the average-case to the best-case scenario.It is an in-place sorting algorithm and its best-case time complexity isΩ(n).It is linear and better than bubble sort,selection sort,and merge sort.In averagecase and worst-case analyses,the complexity estimates are based on its static footprint analyses.Its complexity in worst-case is O(n2)and in average-case isΘ(n^(2)).Smart Bubble sort is capable of adapting itself to the best-case scenario from the average-case scenario at any subsequent stages due to its dynamic and intelligent nature.The Smart Bubble sort outperforms bubble sort,selection sort,and merge sort in the best-case scenario whereas it outperforms bubble sort in the average-case scenario. 展开更多
关键词 Sorting algorithms smart bubble sort FOOTPRINT dynamic footprint time complexity asymptotic analysis
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Efficient Routing Protection Algorithm in Large-Scale Networks
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作者 Haijun Geng Han Zhang Yangyang Zhang 《Computers, Materials & Continua》 SCIE EI 2021年第2期1733-1744,共12页
With an increasing urgent demand for fast recovery routing mechanisms in large-scale networks,minimizing network disruption caused by network failure has become critical.However,a large number of relevant studies have... With an increasing urgent demand for fast recovery routing mechanisms in large-scale networks,minimizing network disruption caused by network failure has become critical.However,a large number of relevant studies have shown that network failures occur on the Internet inevitably and frequently.The current routing protocols deployed on the Internet adopt the reconvergence mechanism to cope with network failures.During the reconvergence process,the packets may be lost because of inconsistent routing information,which reduces the network’s availability greatly and affects the Internet service provider’s(ISP’s)service quality and reputation seriously.Therefore,improving network availability has become an urgent problem.As such,the Internet Engineering Task Force suggests the use of downstream path criterion(DC)to address all single-link failure scenarios.However,existing methods for implementing DC schemes are time consuming,require a large amount of router CPU resources,and may deteriorate router capability.Thus,the computation overhead introduced by existing DC schemes is significant,especially in large-scale networks.Therefore,this study proposes an efficient intra-domain routing protection algorithm(ERPA)in large-scale networks.Theoretical analysis indicates that the time complexity of ERPA is less than that of constructing a shortest path tree.Experimental results show that ERPA can reduce the computation overhead significantly compared with the existing algorithms while offering the same network availability as DC. 展开更多
关键词 Large-scale network shortest path tree time complexity network failure real-time and mission-critical applications
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快速外分类算法设计与分析
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作者 何文趋 《郑州大学学报(理学版)》 CAS 1987年第2期26-30,57,共6页
§1 引言数据库文件的分类是数据处理的重要课题之一,它直接影响数据库的检索效率。目前外分类算法中多数采用分类归并方法[1][2],分类归并过程一般先逐段执行内分类,每次读入内存缓冲区所能容纳的数据,选择一内分类算法将数据整理... §1 引言数据库文件的分类是数据处理的重要课题之一,它直接影响数据库的检索效率。目前外分类算法中多数采用分类归并方法[1][2],分类归并过程一般先逐段执行内分类,每次读入内存缓冲区所能容纳的数据,选择一内分类算法将数据整理成有序串,并根据归并的散布算法输出这些有序串,然后数据在内外存间进行归并,以形成一个最终的有序串。 展开更多
关键词 sort algorithm quick sort time complexity.
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A Novel Hybrid Encryption Method Based on Honey Encryption and Advanced DNA Encoding Scheme in Key Generation
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作者 Nwe Ni Khin Thanda Win 《Journal of Computer and Communications》 2022年第9期22-36,共15页
Nowadays, increased information capacity and transmission processes make information security a difficult problem. As a result, most researchers employ encryption and decryption algorithms to enhance information secur... Nowadays, increased information capacity and transmission processes make information security a difficult problem. As a result, most researchers employ encryption and decryption algorithms to enhance information security domains. As it progresses, new encryption methods are being used for information security. In this paper, a hybrid encryption algorithm that combines the honey encryption algorithm and an advanced DNA encoding scheme in key generation is presented. Deoxyribonucleic Acid (DNA) achieves maximal protection and powerful security with high capacity and low modification rate, it is currently being investigated as a potential carrier for information security. Honey Encryption (HE) is an important encryption method for security systems and can strongly prevent brute force attacks. However, the traditional honeyword encryption has a message space limitation problem in the message distribution process. Therefore, we use an improved honey encryption algorithm in our proposed system. By combining the benefits of the DNA-based encoding algorithm with the improved Honey encryption algorithm, a new hybrid method is created in the proposed system. In this paper, five different lookup tables are created in the DNA encoding scheme in key generation. The improved Honey encryption algorithm based on the DNA encoding scheme in key generation is discussed in detail. The passwords are generated as the keys by using the DNA methods based on five different lookup tables, and the disease names are the input messages that are encoded by using the honey encryption process. This hybrid method can reduce the storage overhead problem in the DNA method by applying the five different lookup tables and can reduce time complexity in the existing honey encryption process. 展开更多
关键词 Honey Encryption DNA Encoding Hybrid Method Data Lookup Tables time complexity Storage Overhead
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Distribution of aluminum species and the characteristics of structure of poly-aluminum-chloride-sulfate(PACS) 被引量:5
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作者 GAO Bao\|yu, YUE Qin\|yan, YU Hui, WANG Yan (Department of Environmental Engineering, Shandong University, Jinan\ 250100, China. E\|mail:bygao@sdu.edu.cn) 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2001年第1期108-114,共7页
A series of poly\|aluminum\|chloride\|sulfate (PACS), which has different basicities (γ) and Al 3+ /SO 2- 4 molar ratio, has been prepared and dried at 105℃ and 65℃, respectively. The distribution of aluminum speci... A series of poly\|aluminum\|chloride\|sulfate (PACS), which has different basicities (γ) and Al 3+ /SO 2- 4 molar ratio, has been prepared and dried at 105℃ and 65℃, respectively. The distribution of aluminum species of PACS was examined, and the effect of γ value, Al 3+ /SO 2- 4 molar ratio, dilution on the distribution of aluminum species of PACS was also investigated by using Al\|ferron timed complex colorimetric method. The IR spectroscopy and X \|ray diffraction were used to study the effect of γ value, Al 3+ /SO 2- 4 molar ratio and the drying temperature on the structure of PACS. The experimental results show that Al 3+ /SO 2- 4 molar ratio has a great effect on the distribution of aluminum species, but the dilution has a little effect on the distribution of aluminum species. The lower the Al 3+ /SO 2- 4 molar ratio, the higher the proportions of the polymer and colloidal species in PACS. The polymeric degree of PACS was related to γ value and Al 3+ /SO 2- 4 molar ratio. Drying temperature has an influence on the structure and the solubility of solid PACS products. 展开更多
关键词 flocculant PACS SPECIES structure Al\|ferron timed complex colorimetric method IR spectroscopy X \|ray diffractio`
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Constraining the Timing of the Molopo Farms Complex Emplacement and Provenance of Its Country Rock
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作者 Michiel O.de Kock Livhuwani Ravhura +2 位作者 Clarisa Vorster Nicolas J.Beukes Ashley P.Gumsley 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第S1期78-,共1页
The Molopo Farms Complex(MFC)is a 13000 km2layered,mafic-ultramafic intrusion straddling the southern border of Botswana with South Africa.It does not outcrop due to Cenozoic cover,but is believed to intrude
关键词 Constraining the Timing of the Molopo Farms Complex Emplacement and Provenance of Its Country Rock MFC
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Complex Time Series Analysis Based on Conditional Random Fields
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作者 Yanjie Wei Haifeng Guo +3 位作者 Donghua Yang Mengmeng Li Bo Zheng Hongzhi Wang 《国际计算机前沿大会会议论文集》 EI 2023年第1期221-232,共12页
A fundamental problem with complex time series analysis involves data prediction and repair.However,existing methods are not accurate enough for complex and multidimensional time series data.In this paper,we propose a... A fundamental problem with complex time series analysis involves data prediction and repair.However,existing methods are not accurate enough for complex and multidimensional time series data.In this paper,we propose a novel approach,a complex time series predic-tion model,which is based on the conditional randomfield(CRF)and recurrent neural network(RNN).This model can be used as an upper-level predictor in the stacking process or be trained using deep learning methods.Our approach is more accurate than existing methods in some suitable scenarios,as shown in the experimental results. 展开更多
关键词 complex time series missing data conditional randomfield STACKING deep learning
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Pinning Synchronization of Discrete-Time Complex Networks with Different Time-Varying Delays 被引量:2
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作者 ZHANG Qunjiao WU Xiaoqun LIU Jie 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2019年第6期1560-1571,共12页
This paper investigates pinning synchronization of discrete-time complex networks with differen t time-varying delays.An important lemma is presen ted and proved,t hen detailed analysis is given to yield some synchron... This paper investigates pinning synchronization of discrete-time complex networks with differen t time-varying delays.An important lemma is presen ted and proved,t hen detailed analysis is given to yield some synchronization criteria for this kind of net works.The results provide an effective way to synchronize discrete-time complex networks by reducing control cost.Furthermore,these theoretical results are illustrated by a complex network via two kinds of pinning schemes.Numerical simulations verify the feasibil计y of the proposed methods. 展开更多
关键词 Different time-varying delays discrete・time complex networks PINNING SYNCHRONIZATION
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A novel strong tracking cubature Kalman filter and its application in maneuvering target tracking 被引量:22
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作者 An ZHANG Shuida BAO +1 位作者 Fei GAO Wenhao BI 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2019年第11期2489-2502,共14页
The fading factor exerts a significant role in the strong tracking idea. However, traditional fading factor introduction method hinders the accuracy and robustness advantages of current strong-tracking-based nonlinear... The fading factor exerts a significant role in the strong tracking idea. However, traditional fading factor introduction method hinders the accuracy and robustness advantages of current strong-tracking-based nonlinear filtering algorithms such as Cubature Kalman Filter(CKF) since traditional fading factor introduction method only considers the first-order Taylor expansion. To this end, a new fading factor idea is suggested and introduced into the strong tracking CKF method.The new fading factor introduction method expanded the number of fading factors from one to two with reselected introduction positions. The relationship between the two fading factors as well as the general calculation method can be derived based on Taylor expansion. Obvious superiority of the newly suggested fading factor introduction method is demonstrated according to different nonlinearity of the measurement function. Equivalent calculation method can also be established while applied to CKF. Theoretical analysis shows that the strong tracking CKF can extract the thirdorder term information from the residual and thus realize second-order accuracy. After optimizing the strong tracking algorithm process, a Fast Strong Tracking CKF(FSTCKF) is finally established. Two simulation examples show that the novel FSTCKF improves the robustness of traditional CKF while minimizing the algorithm time complexity under various conditions. 展开更多
关键词 Algorithm time complexity Cubature Kalman filter Nonlinear filtering ROBUSTNESS Strong tracking filter
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Combinatorial Algorithms for Reverse Selective Undesirable Center Location Problems on Cycle Graphs
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作者 Roghayeh Etemad Behrooz Alizadeh 《Journal of the Operations Research Society of China》 EI CSCD 2017年第3期347-361,共15页
This paper deals with a general variant of the reverse undesirable(obnoxious)center location problem on cycle graphs.Given a‘selective’subset of the vertices of the underlying cycle graph as location of the existin... This paper deals with a general variant of the reverse undesirable(obnoxious)center location problem on cycle graphs.Given a‘selective’subset of the vertices of the underlying cycle graph as location of the existing customers,the task is to modify the edge lengths within a given budget such that the minimum of distances between a predetermined undesirable facility location and the customer points is maximized under the perturbed edge lengths.We develop a combinatorial O(n log n)algorithm for the problem with continuous modifications.For the uniform-cost model,we solve this problem in linear time by an improved algorithm.Furthermore,exact solution methods are proposed for the problem with integer modifications. 展开更多
关键词 Undesirable center location Reverse optimization Combinatorial optimization time complexity
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Optimal Algorithms for Integer Inverse Undesirable p-Median Location Problems on Weighted Extended Star Networks
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作者 Esmaeil Afrashteh Behrooz Alizadeh Fahimeh Baroughi 《Journal of the Operations Research Society of China》 EI CSCD 2021年第1期99-117,共19页
This paper is concerned with the problem of modifying the edge lengths of a weighted extended star network with n vertices by integer amounts at the minimum total cost subject to be given modification bounds so that a... This paper is concerned with the problem of modifying the edge lengths of a weighted extended star network with n vertices by integer amounts at the minimum total cost subject to be given modification bounds so that a set of p prespecified vertices becomes an undesirable p-median location on the perturbed network.We call this problem as the integer inverse undesirable p-median location model.Exact combinatorial algorithms with O(p2n logn)and O(p2(n logn+n log nmax))running times are proposed for solving the problem under the weighted rectilinear and weighted Chebyshev norms,respectively.Furthermore,it is shown that the problem under the weighted sum-type Hamming distance with uniform modification bounds can be solved in O(p-n log n)time. 展开更多
关键词 Undesirable p-median location Combinatorial optimization Inverse optimization time complexity
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