The Cross-domain Heuristic search Challenge(CHeSC)is a competition focused on creating efficient search algorithms adaptable to diverse problem *** hyper-heuristics are a class of algorithms that dynamically choose he...
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The Cross-domain Heuristic search Challenge(CHeSC)is a competition focused on creating efficient search algorithms adaptable to diverse problem *** hyper-heuristics are a class of algorithms that dynamically choose heuristics during the search *** selection hyper-heuristics have different imple-mentation ***,comparisons between them are lacking in the literature,and previous works have not highlighted the beneficial and detrimental implementation methods of different *** question is how to effectively employ them to produce an efficient search ***,the algorithms that competed in the inaugural CHeSC have not been collectively *** work conducts a review analysis of the top twenty competitors from this competition to identify effective and ineffective strategies influencing algorithmic performance.A summary of the main characteristics and classification of the algorithms is *** analysis underlines efficient and inefficient methods in eight key components,including search points,search phases,heuristic selection,move acceptance,feedback,Tabu mechanism,restart mechanism,and low-level heuristic parameter *** review analyzes the components referencing the competition’s final leaderboard and discusses future research directions for these *** effective approaches,identified as having the highest quality index,are mixed search point,iterated search phases,relay hybridization selection,threshold acceptance,mixed learning,Tabu heuristics,stochastic restart,and dynamic *** are also compared with recent trends in *** work enhances the understanding of selection hyper-heuristics,offering valuable insights for researchers and practitioners aiming to develop effective search algorithms for diverse problem domains.
Recently, researchers have mainly been interested only in the search for data content that are globally similar to the query and not in the search for inside data items. This paper presents an algorithm, called a gene...
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Recently, researchers have mainly been interested only in the search for data content that are globally similar to the query and not in the search for inside data items. This paper presents an algorithm, called a generalized virtual node (GVN) algorithm, to search for data items where parts (subdatatype) are similar to the incoming query. We call this "subdatatype"-based multimedia retrieval. Each multimedia datatype, such as image and audio is represented in this paper as a k-dimensional signal in the spatio-temporal domain. A k-dimensional signal is transformed into characteristic features and these features are stored in a hierarchical multidimensional structure, called the k-tree. Each node on the k-tree contains partial content corresponding to the spatial and/or temporal positions in the data. The k-tree structure allows us to build a unified retrieval model for any types of multimedia data. It also eliminates unnecessary comparisons of cross-media querying. The experimental results of the use of the new GVN algorithm for "subaudio" and "subimage" retrievals show that it takes much less retrieval times than other earlier algorithms such as brute-force and the partial-matching algorithm, while the accuracy is acceptable.
In this paper, we take an abstract view of search by describing search procedures via particular kinds of proofs in type theory. We rely on the proofs-as-programs interpretation to extract programs from our proofs. Us...
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In this paper, we take an abstract view of search by describing search procedures via particular kinds of proofs in type theory. We rely on the proofs-as-programs interpretation to extract programs from our proofs. Using these techniques we explore, in depth, a large family of search problems by parameterizing the specification of the problem. A constructive proof is presented which has as its computational content a correct search procedure for these problems. We show how a classical extension to an otherwise constructive system can be used to describe a typical use of the nonlocal control operator call/cc. Using the classical typing of nonlocal control we extend our purely constructive proof to incorporate a sophisticated backtracking technique known as 'conflict-directed backjumping' (CBJ). A variant of this proof is formalized in Nupr1 yielding a correct-by-construction implementation of CBJ. The extracted program has been translated into Scheme and serves as the basis for an implementation of a new solution to the Hamiltonian circuit problem. This paper demonstrates a nontrivial application of the proofs-as-programs paradigm by applying the technique to the derivation of a sophisticated search algorithm;also, it shows the generality of the resulting implementation by demonstrating its application in a new problem domain for CBJ. (C) 2000 Elsevier Science B.V. All rights reserved.
A novel search technique called highway search is introduced. The search technique relies on a highway simulation which takes several homogeneous walks through a (possibly infinite) state space. Furthermore, we provid...
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A novel search technique called highway search is introduced. The search technique relies on a highway simulation which takes several homogeneous walks through a (possibly infinite) state space. Furthermore, we provide a memory-efficient algorithm that approximates a highway search and we prove that. under particular conditions, they coincide. The effectiveness of highway search is compared to two mainstream search techniques, viz. random search and randomised depth-first search. Our results demonstrate that randomised depth-first search explores the least amount of states in the effort of finding states of interest, whereas a highways search yields the shortest witnessing traces to such states. (C) 2008 Elsevier Inc. All rights reserved.
Media streaming delivery in wireless ad hoc networks is challenging due to the stringent resource restrictions,po-tential high loss rate and the decentralized architecture. To support long and high-quality streams,one...
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Media streaming delivery in wireless ad hoc networks is challenging due to the stringent resource restrictions,po-tential high loss rate and the decentralized architecture. To support long and high-quality streams,one viable approach is that a media stream is partitioned into segments,and then the segments are replicated in a network and served in a peer-to-peer(P2P) fashion. However,the searching strategy for segments is one key problem with the approach. This paper proposes a hybrid ants-like search algorithm(HASA) for P2P media streaming distribution in ad hoc networks. It takes the advantages of random walks and ants-like algorithms for searching in unstructured P2P networks,such as low transmitting latency,less jitter times,and low unnecessary traffic. We quantify the performance of our scheme in terms of response time,jitter times,and network messages for media streaming distribution. Simulation results showed that it can effectively improve the search efficiency for P2P media streaming distribution in ad hoc networks.
Seven algorithms used to search for solutions in dynamic planning and execution problems are compared. The specific problem is endgame moves for the board game RISK. This paper concentrates on comparison of search met...
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Seven algorithms used to search for solutions in dynamic planning and execution problems are compared. The specific problem is endgame moves for the board game RISK. This paper concentrates on comparison of search methods for the best plan using a fixed evaluation function, fixed time to plan, and randomly generated situations that correspond to endgames in RISK with eight remaining players. The search strategies compared are depth-first, breadth-first, best-first, random walk, gradient ascent, simulated annealing, and evolutionary computation. The approaches are compared for each example based on the number of opponents eliminated, plan completion probability, and value of ending position (if the moves do not complete the game). Simulation results indicate that the evolutionary approach is superior to the other methods in 85% of the cases considered. Among the other algorithms, simulated annealing is the most suitable for this problem.
One of the key challenges in ad-hoc networks is the resource discovery *** efciently&quickly the queried resource/object can be resolved in such a highly dynamic self-evolving network is the underlying question?Br...
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One of the key challenges in ad-hoc networks is the resource discovery *** efciently&quickly the queried resource/object can be resolved in such a highly dynamic self-evolving network is the underlying question?Broadcasting is a basic technique in the Mobile Ad-hoc Networks(MANETs),and it refers to sending a packet from one node to every other node within the transmission *** is a type of broadcast where the received packet is retransmitted once by every *** naive ooding technique oods the network with query messages,while the random walk scheme operates by contacting subsets of each node’s neighbors at every step,thereby restricting the search *** earlier works have mainly focused on the simulation-based analysis of ooding technique,and its variants,in a wired network ***,there have been some empirical studies in peer-to-peer(P2P)networks,the analytical results are still lacking,especially in the context of mobile P2P *** this article,we mathematically model different widely used existing search techniques,and compare with the proposed improved random walk method,a simple lightweight approach suitable for the non-DHT *** provide analytical expressions to measure the performance of the different ooding-based search techniques,and our proposed *** analytically derive 3 relevant key performance measures,i.e.,the *** of steps needed to nd a resource,the probability of locating a resource,and the *** of messages generated during the entire search process.
Web services are designed to standardize interactions between heterogeneous applications using Internet technologies. Within the framework of Internet search technologies, Web services provide structured channels to a...
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ISBN:
(纸本)9780769529240
Web services are designed to standardize interactions between heterogeneous applications using Internet technologies. Within the framework of Internet search technologies, Web services provide structured channels to access search engines and web-accessible databases. Our work involves research in methods to discover Web Service Description Language (WSDL) documents, which provide interface formats, expected data-types, supported protocols and precise service endpoints. This project extends current discovery research through use of the Google Web service, UDDI category searching, and private registry querying with preliminary experiments resulting in a very high percentage of success. The goal is to find WSDL documents for a given domain name, parse the desired service document to obtain invocation formats, and automatically invoke the Web service. Contributions of this research will support enhancements of HTML-dependent search tools by providing access to data inaccessible through surface HTML interfaces.
In the design of production lines, the classical approach to the buffer allocation problem (BAP) is to use a search algorithm in association with an evaluative algorithm to obtain the mathematical optimum of the speci...
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In the design of production lines, the classical approach to the buffer allocation problem (BAP) is to use a search algorithm in association with an evaluative algorithm to obtain the mathematical optimum of the specified objective function. In practice, a choice often has to be made regarding which search algorithm to use for the efficient solution of the BAP. This paper gives the results of a carefully selected set of experiments on short (K=number of stations=3, 4,, 11 stations), medium length (K=12, 13,, 30 stations) and long lines (K=40, 50, , 100 stations) and, within each line, small N (N=total number of buffer slots=K/2 if K is even;= (K-1)/2 if K is odd), medium N (N=K+1) and large N (N=2K) to evaluate the effectiveness of the following five search algorithms: simulated annealing, genetic, tabu search, myopic and complete enumeration (where possible). The production lines are balanced and the single exponential machine at each station is perfectly reliable. All the experiments were run on a readily available desktop PC with the following specifications: Windows XP Professional Version 2002 Service Pack 3, Pentium (R) Dual-Core CPU E5300@2.60GHz, 2.00GB RAM. The measures of performance used are CPU time required and closeness to the maximum throughput achieved. The five search algorithms are ranked in respect to these two measures and certain findings regarding their performance over the experimental set are noted. The distributions of buffer slots to storage areas for the algorithm(s) leading to maximum throughput are examined and certain patterns are found, leading to indications for design rules. Based on the results of the above experiments, two additional sets of experiments were carried out, one using the simulated annealing algorithm for production lines of K=3 to 20 and N=1 to 20 (accounting for a total number of 360 different production lines) and another using the myopic algorithm for production lines of K=3 to 80 and N=1 to 120 (accounting for a t
In this paper, we give the geometric pictures for quantum search algorithms in decomposed form, namely in terms of a phase rotation of the marked state and a phase rotation about the average. We apply this formalism t...
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In this paper, we give the geometric pictures for quantum search algorithms in decomposed form, namely in terms of a phase rotation of the marked state and a phase rotation about the average. We apply this formalism to various quantum search algorithms, and give explicit interpretations of the standard Grover algorithm, arbitrary phase rotations, phase matching and fixed-point search algorithm. The pictures straightforwardly show how state vectors evolve during the search process. These results are helpful in understanding how the quantum search algorithms work.
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