Symmetry最新文献_第7页

Five-Element Cycle Optimization Algorithm Based on an Integrated Mutation Operator for the Traveling Thief Problem 基于综合突变算子的旅行小偷问题五要素循环优化算法

Symmetry Pub Date : 2024-09-04 DOI: 10.3390/sym16091153

Yue Xiang, Jingjing Guo, Zhengyan Mao, Chao Jiang, Mandan Liu

{"title":"Five-Element Cycle Optimization Algorithm Based on an Integrated Mutation Operator for the Traveling Thief Problem","authors":"Yue Xiang, Jingjing Guo, Zhengyan Mao, Chao Jiang, Mandan Liu","doi":"10.3390/sym16091153","DOIUrl":"https://doi.org/10.3390/sym16091153","url":null,"abstract":"This paper presents a novel algorithm named Five-element Cycle Integrated Mutation Optimization (FECOIMO) for solving the Traveling Thief Problem (TTP). The algorithm introduces a five-element cycle structure that integrates various mutation operations to enhance both global exploration and local exploitation capabilities. In experiments, FECOIMO was extensively tested on 39 TTP instances of varying scales and compared with five common metaheuristic algorithms: Enhanced Simulated Annealing (ESA), Improved Grey Wolf Optimization Algorithm (IGWO), Improved Whale Optimization Algorithm (IWOA), Genetic Algorithm (GA), and Profit-Guided Coordination Heuristic (PGCH). The experimental results demonstrate that FECOIMO outperforms the other algorithms across all instances, particularly excelling in large-scale instances. The results of the Friedman test show that FECOIMO significantly outperforms other algorithms in terms of average solution, maximum solution, and solution standard deviation. Additionally, although FECOIMO has a longer execution time, its complexity is comparable to that of other algorithms, and the additional computational overhead in solving complex optimization problems translates into better solutions. Therefore, FECOIMO has proven its effectiveness and robustness in handling complex combinatorial optimization problems.","PeriodicalId":501198,"journal":{"name":"Symmetry","volume":"71 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142208988","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Explicit form for the Most General Lorentz Transformation Revisited 最一般洛伦兹变换的显式再探讨

Symmetry Pub Date : 2024-09-04 DOI: 10.3390/sym16091155

Howard E. Haber

引用次数: 0

Symmetry-Based Urban Rail Transit Network Planning Using Two-Stage Robust Optimization 利用两阶段稳健优化进行基于对称性的城市轨道交通网络规划

Symmetry Pub Date : 2024-09-04 DOI: 10.3390/sym16091149

Zhaoguo Huang, Changxi Ma

{"title":"Symmetry-Based Urban Rail Transit Network Planning Using Two-Stage Robust Optimization","authors":"Zhaoguo Huang, Changxi Ma","doi":"10.3390/sym16091149","DOIUrl":"https://doi.org/10.3390/sym16091149","url":null,"abstract":"To address the symmetry-related resilience issues of stations and lines in urban rail transit networks, we propose a two-stage robust optimization-based approach for urban rail transit network planning. In this context, resilience is conceptualized as the ability of the network to maintain its operational symmetry under normal and disruptive conditions. Firstly, we used passenger flow distributions as decision variables to construct a two-stage symmetry-based urban rail transit network planning model, aiming to simultaneously minimize the total cost and total operating time of the network while preserving its functional symmetry. Secondly, we designed a hybrid evolutionary algorithm with chromosomes having a two-layer encoding structure, where the Niched Pareto Genetic Algorithm served as the main algorithmic framework, and a Large Neighborhood Search mechanism was designed to optimize the connectivity gene layer of individuals, ensuring the symmetry of network connectivity. Finally, we conducted computational verification on randomly generated instances to confirm the effectiveness of the model and algorithm. The experimental results demonstrated that our method could find two sets of Pareto optimal solutions for cost preference and time preference, thereby preserving the operational symmetry of the network under normal and damaged conditions, as well as reducing the total operating time. This effectively improved the overall efficiency and resilience of the network. Our designed hybrid evolutionary algorithm converged to satisfactory objective values in the early iterations, exhibiting strong search and optimization performance and effectively solving the two-stage symmetry-based urban rail transit network planning model.","PeriodicalId":501198,"journal":{"name":"Symmetry","volume":"11 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142208982","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Exploring Properties and Applications of Laguerre Special Polynomials Involving the Δh Form 探索涉及 Δh 形式的拉盖尔特殊多项式的性质和应用

Symmetry Pub Date : 2024-09-04 DOI: 10.3390/sym16091154

Noor Alam, Shahid Ahmad Wani, Waseem Ahmad Khan, Fakhredine Gassem, Anas Altaleb

引用次数: 0

Local-Energy-Conservation-Based Decomposition Method for Wall Friction and Heat Flux 基于局部能量守恒的墙面摩擦和热通量分解法

Symmetry Pub Date : 2024-09-04 DOI: 10.3390/sym16091147

Mingzhi Tang, Wenfeng Zhou, Yanchao Hu, Gang Wang, Yanguang Yang

{"title":"Local-Energy-Conservation-Based Decomposition Method for Wall Friction and Heat Flux","authors":"Mingzhi Tang, Wenfeng Zhou, Yanchao Hu, Gang Wang, Yanguang Yang","doi":"10.3390/sym16091147","DOIUrl":"https://doi.org/10.3390/sym16091147","url":null,"abstract":"A novel decomposition method that adheres to both local time translation symmetry and spatial rotational symmetry is proposed in this study, thereby extending the limitations of existing methods, which are typically restricted to quasi-two-dimensional configurations. Grounded in the FIK and RD identities, this method provides a clear physical and reliable interpretation suitable for arbitrary-curvature profiles. Utilizing this method, an analysis of the aerothermodynamic characteristics of the bistable states of curved compression ramp flows was conducted. The results reveal that the generation of undisturbed and peak Cf is dominated by viscous dissipation. Specifically, flow separation happens when all of the energy input from the work exerted by the adverse pressure gradient (APG) is insufficient to be entirely converted into local viscous dissipation and kinetic energy. Furthermore, the propensity for flow separation at higher wall temperatures is firstly elucidated quantitatively from the perspective of the work by the APG. The peak heat flux is predominantly triggered by the work of viscous stress, with the secondary contribution from energy transport playing a more significant role in the generation of the peak heat flux of the separation state than that of the attachment state.","PeriodicalId":501198,"journal":{"name":"Symmetry","volume":"47 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142208981","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Object Skill Advantage in Infants with a Hand Preference 手部偏好婴儿的物体技能优势

Symmetry Pub Date : 2024-09-04 DOI: 10.3390/sym16091148

Emily C. Marcinowski, George F. Michel, Eliza L. Nelson

{"title":"Object Skill Advantage in Infants with a Hand Preference","authors":"Emily C. Marcinowski, George F. Michel, Eliza L. Nelson","doi":"10.3390/sym16091148","DOIUrl":"https://doi.org/10.3390/sym16091148","url":null,"abstract":"How infants engage with objects changes dramatically over the first year of life. While some infants exhibit a consistent hand preference for acquiring objects during this period, others have no identifiable preference. The goal of this study was to test whether lateralization confers an advantage in the development of early object management skills. We examined whether lateralized infants show different rates of growth in how they interact with multiple objects as compared to infants without a hand preference. In a longitudinal study consisting of seven monthly visits from 6 to 12 months, 303 infants were assessed for their hand preference and object management skill (i.e., holding up to three objects). Group-Based Trajectory Modeling (GBTM) identified the following three hand preference trajectory groups: Left, Right, and No Preference (NP). A Hierarchical Generalized Linear Model (HGLM) with the NP infants as the reference group for statistical comparisons revealed that while all the infants showed similar trends in their object management skills over time, the lateralized infants had an advantage over the non-lateralized infants. The infants in the Right and Left groups transitioned from holding one to two objects more quickly relative to the NP infants. Further research is needed to determine if this early object skill advantage cascades to a more complex handling of multiple objects.","PeriodicalId":501198,"journal":{"name":"Symmetry","volume":"41 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142208986","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Predictor Laplace Fractional Power Series Method for Finding Multiple Solutions of Fractional Boundary Value Problems 用于寻找分数边界问题多解的预测拉普拉斯分数幂级数法

Symmetry Pub Date : 2024-09-04 DOI: 10.3390/sym16091152

Abedel-Karrem Alomari, Wael Mahmoud Mohammad Salameh, Mohammad Alaroud, Nedal Tahat

引用次数: 0

Stability Analysis of Stable Circular Orbit in Multi-Static Black Hole Spacetime 多静态黑洞时空中稳定圆形轨道的稳定性分析

Symmetry Pub Date : 2024-09-03 DOI: 10.3390/sym16091140

Zefang Fan, Yu Wang, Xianggao Wang

引用次数: 0

Analysis of a Bifurcation and Stability of Equilibrium Points for Jeffrey Fluid Flow through a Non-Uniform Channel 杰弗里流体流经非均匀通道时平衡点的分岔和稳定性分析

Symmetry Pub Date : 2024-09-03 DOI: 10.3390/sym16091144

Mary G. Thoubaan, Dheia G. Salih Al-Khafajy, Abbas Kareem Wanas, Daniel Breaz, Luminiţa-Ioana Cotîrlă

引用次数: 0

On the Interpretation of Cosmic Acceleration 关于宇宙加速度的解释

Symmetry Pub Date : 2024-09-03 DOI: 10.3390/sym16091141

Enrique Gaztanaga

{"title":"On the Interpretation of Cosmic Acceleration","authors":"Enrique Gaztanaga","doi":"10.3390/sym16091141","DOIUrl":"https://doi.org/10.3390/sym16091141","url":null,"abstract":"In relativity, the Newtonian concepts of velocity and acceleration are observer-dependent quantities that vary with the chosen frame of reference. It is well established that in the comoving frame, cosmic expansion is currently accelerating; however, in the rest frame, this expansion is actually decelerating. In this paper, we explore the implications of this distinction. The traditional measure of cosmic acceleration, denoted by q, is derived from the comoving frame and describes the acceleration of the scale factor a for a 3D space-like homogeneous sphere. We introduce a new parameter qE representing the acceleration experienced between observers within the light cone. By comparing qE to the traditional q using observational data from Type Ia supernovae (SN) and the radial clustering of galaxies and quasars (BAO)—including the latest results from DESI2024—our analysis demonstrates that qE aligns more closely with these data. The core argument of the paper is that Λ—regardless of its origin—creates an event horizon that divides the manifold into two causally disconnected regions analogous to conditions inside a black hole’s interior, thereby allowing for a rest-frame perspective qE in which cosmic expansion appears to be decelerating and the horizon acts like a friction term. Such a horizon suggests that the universe cannot maintain homogeneity outside. The observed cosmological constant Λ can then be interpreted not as a driver of new dark energy or a modification of gravity but as a boundary term exerting an attractive force, akin to a rubber band, resisting further expansion and preventing event horizon crossings. This interpretation calls for a reconsideration of current cosmological models and the assumptions underlying them.","PeriodicalId":501198,"journal":{"name":"Symmetry","volume":"2 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142209039","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0