Natural Computing最新文献_第3页

Turning machines: a simple algorithmic model for molecular robotics. 旋转机器：分子机器人学的简单算法模型。

IF 1.7 4区计算机科学

Natural Computing Pub Date : 2024-01-01 Epub Date: 2022-02-22 DOI: 10.1007/s11047-022-09880-8

Irina Kostitsyna, Cai Wood, Damien Woods

{"title":"Turning machines: a simple algorithmic model for molecular robotics.","authors":"Irina Kostitsyna, Cai Wood, Damien Woods","doi":"10.1007/s11047-022-09880-8","DOIUrl":"10.1007/s11047-022-09880-8","url":null,"abstract":"Molecular robotics is challenging, so it seems best to keep it simple. We consider an abstract molecular robotics model based on simple folding instructions that execute asynchronously. Turning Machines are a simple 1D to 2D folding model, also easily generalisable to 2D to 3D folding. A Turning Machine starts out as a line of connected monomers in the discrete plane, each with an associated turning number. A monomer turns relative to its neighbours, executing a unit-distance translation that drags other monomers along with it, and through collective motion the initial set of monomers eventually folds into a programmed shape. We provide a suite of tools for reasoning about Turning Machines by fully characterising their ability to execute line rotations: executing an almost-full line rotation of <math><mrow><mn>5</mn> <mi>π</mi> <mo>/</mo> <mn>3</mn></mrow> </math> radians is possible, yet a full <math><mrow><mn>2</mn> <mi>π</mi></mrow> </math> rotation is impossible. Furthermore, line rotations up to <math><mrow><mn>5</mn> <mi>π</mi> <mo>/</mo> <mn>3</mn></mrow> </math> are executed efficiently, in <math><mrow><mi>O</mi> <mo>(</mo> <mo>log</mo> <mi>n</mi> <mo>)</mo></mrow> </math> expected time in our continuous time Markov chain time model. We then show that such line-rotations represent a fundamental primitive in the model, by using them to efficiently and asynchronously fold shapes. In particular, arbitrarily large zig-zag-rastered squares and zig-zag paths are foldable, as are y-monotone shapes albeit with error (bounded by perimeter length). Finally, we give shapes that despite having paths that traverse all their points, are in fact impossible to fold, as well as techniques for folding certain classes of (scaled) shapes without error. Our approach relies on careful geometric-based analyses of the feats possible and impossible by a very simple robotic system, and pushes conceptional hardness towards mathematical analysis and away from molecular implementation.","PeriodicalId":49783,"journal":{"name":"Natural Computing","volume":"23 2","pages":"407-430"},"PeriodicalIF":1.7,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11297016/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141890710","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Correction: Cellular automata simulations of the sintering behavior of ceramics driven by surface energy reduction 更正：由表面能降低驱动的陶瓷烧结行为的细胞自动机模拟

IF 2.1 4区计算机科学

Natural Computing Pub Date : 2023-12-18 DOI: 10.1007/s11047-023-09970-1

Garrido-Regife Laura, Jiménez-Morales Francisco, González-Sánchez Manuela, Rivero-Antúnez Pedro, Morales-Flórez Víctor

引用次数: 0

Evolving ensembles of heuristics for the travelling salesman problem 旅行商问题的启发式演化集合

4区计算机科学

Natural Computing Pub Date : 2023-10-25 DOI: 10.1007/s11047-023-09968-9

Francisco J. Gil-Gala, Marko Durasević, María R. Sierra, Ramiro Varela

{"title":"Evolving ensembles of heuristics for the travelling salesman problem","authors":"Francisco J. Gil-Gala, Marko Durasević, María R. Sierra, Ramiro Varela","doi":"10.1007/s11047-023-09968-9","DOIUrl":"https://doi.org/10.1007/s11047-023-09968-9","url":null,"abstract":"Abstract The Travelling Salesman Problem (TSP) is a well-known optimisation problem that has been widely studied over the last century. As a result, a variety of exact and approximate algorithms have been proposed in the literature. When it comes to solving large instances in real-time, greedy algorithms guided by priority rules represent the most common approach, being the nearest neighbour (NN) heuristic one of the most popular rules. NN is quite general but it is too simple and so it may not be the best choice in some cases. Alternatively, we may design more sophisticated heuristics considering the particular features of families of instances. To do that, we have to consider problem attributes other than the proximity of the next city to build priority rules. However, this process may not be easy for humans and so it is often addressed by some learning procedure. In this regard, hyper-heuristics as Genetic Programming (GP) stands as one of the most popular approaches. Furthermore, a single heuristic, even being good in average, may not be good for a number of instances of a given set. For this reason, the use of ensembles of heuristics is often a good alternative, which raises the problem of building ensembles from a given set of heuristic rules. In this paper, we study the application of two kinds of ensembles to the TSP. Given a set of TSP instances having similar characteristics, we firstly exploit a GP to build a set of heuristics involving a number of problem attributes, and then we build ensembles combining these heuristics by means of a Genetic Algorithm (GA). The experimental study provided valuable insights into the construction and utilisation of single rules and ensembles. It clearly demonstrated that the performance of ensembles justifies the time invested when compared to using individual heuristics.","PeriodicalId":49783,"journal":{"name":"Natural Computing","volume":"32 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135113957","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Neighbourhood search for energy minimisation in flexible job shops under fuzziness 模糊条件下弹性工作间的邻里能量最小化搜索

4区计算机科学

Natural Computing Pub Date : 2023-10-18 DOI: 10.1007/s11047-023-09967-w

Pablo García Gómez, Camino R. Vela, Inés González-Rodríguez

{"title":"Neighbourhood search for energy minimisation in flexible job shops under fuzziness","authors":"Pablo García Gómez, Camino R. Vela, Inés González-Rodríguez","doi":"10.1007/s11047-023-09967-w","DOIUrl":"https://doi.org/10.1007/s11047-023-09967-w","url":null,"abstract":"Abstract Uncertainty pervades real life and supposes a challenge for all industrial processes as it makes it difficult to predict the outcome of otherwise risk-free activities. In particular, time deviation from projected objectives is one of the main sources of economic losses in manufacturing, not only for the delay in production but also for the energy consumed by the equipment during the additional unexpected time they have to work to complete their labour. In this work we deal with uncertainty in the flexible job shop, one of the foremost scheduling problems due to its practical applications. We show the importance of a good model to avoid introducing unwanted imprecision and producing artificially pessimistic solutions. In our model, the total energy is decomposed into the energy required by resources when they are actively processing an operation and the energy consumed by these resources simply for being switched on. We propose a set of metrics and carry out an extensive experimental analysis that compares our proposal with the more straightforward alternative that directly translates the deterministic model. We also define a local search neighbourhood and prove that it can reach an optimal solution starting from any other solution. Results show the superiority of the new model and the good performance of the new neighbourhood.","PeriodicalId":49783,"journal":{"name":"Natural Computing","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135883124","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Parallel pairwise operations on data stored in DNA: sorting, XOR, shifting, and searching 对存储在DNA中的数据进行并行成对操作:排序、异或、移位和搜索

4区计算机科学

Natural Computing Pub Date : 2023-09-21 DOI: 10.1007/s11047-023-09964-z

Arnav Solanki, Tonglin Chen, Marc Riedel

引用次数: 0

Programmable single-stranded architectures for computing 用于计算的可编程单链架构

4区计算机科学

Natural Computing Pub Date : 2023-09-01 DOI: 10.1007/s11047-023-09963-0

Yu Kihara, Shinnosuke Seki

引用次数: 0

Optimal safe driving dynamics for autonomous interacting vehicles 自动交互车辆的最优安全驾驶动力学