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81.
The research for the new algorithm is in the forward position and an issue of general interest in chemometrics all along.A novel chemometrics method,Chemical Ant Colony Algorithm,has first been developed.In this paper,the basic principle,theevaluation function,and the parameter choice were discussed.This method has been successfully applied to the fitting of nonlinear multivariate function and the optimization of test conditions in chrome-azure-S-Al spctrophotometric system.The sum of residual square of the results is 0.0009,which has reached a good convergence result.  相似文献   
82.
The classical sequencing by hybridization takes into account a binary information about sequence composition. A given element from an oligonucleotide library is or is not a part of the target sequence. However, the DNA chip technology has been developed and it enables to receive a partial information about multiplicity of each oligonucleotide the analyzed sequence consist of. Currently, it is not possible to assess the exact data of such type but even partial information should be very useful.Two realistic multiplicity information models are taken into consideration in this paper. The first one, called “one and many” assumes that it is possible to obtain information if a given oligonucleotide occurs in a reconstructed sequence once or more than once. According to the second model, called “one, two and many”, one is able to receive from biochemical experiment information if a given oligonucleotide is present in an analyzed sequence once, twice or at least three times.An ant colony optimization algorithm has been implemented to verify the above models and to compare with existing algorithms for sequencing by hybridization which utilize the additional information. The proposed algorithm solves the problem with any kind of hybridization errors. Computational experiment results confirm that using even the partial information about multiplicity leads to increased quality of reconstructed sequences. Moreover, they also show that the more precise model enables to obtain better solutions and the ant colony optimization algorithm outperforms the existing ones.Test data sets and the proposed ant colony optimization algorithm are available on: http://bioserver.cs.put.poznan.pl/download/ACO4mSBH.zip.  相似文献   
83.
Hong Shu 《Tetrahedron》2010,66(25):4428-6247
The efficient and expeditious syntheses of both enantiomers of the amphibian alkaloid cis-225H have been achieved. Utilizing a common cis-2,5-disubstituted pyrrolidine building block derived from (+)-2-tropinone, the enantioselective syntheses have established the absolute configuration of these alkaloids as (+)-(2R,5S) and (−)-(5S,2R).  相似文献   
84.
蚁群算法在近红外光谱定量分析中的应用研究   总被引:2,自引:0,他引:2  
蚁群算法是新近发展的基于群体智能的仿生优化算法,它模拟蚂蚁的觅食行为来解决复杂的组合优化问题。蚁群算法的优点是智能搜索、全局优化、鲁棒性、分布式计算和容易与其他算法相结合等。近红外光谱定量分析技术在很多领域得到广泛的应用,而其关键技术环节之一是建立近红外光谱测量数据的多元校正模型。文章将蚁群算法应用于近红外光谱定量分析中,建立了谷物样品的傅里叶变换近红外漫反射光谱和谷物中蛋白质含量的定量分析模型,得到了较好的结果。校准集的相关系数与相对标准偏差分别为0.943和3.41%,预测集的相关系数与相对标准偏差分别为0.913和4.67%。  相似文献   
85.
This study proposes an improved solution algorithm using ant colony optimization (ACO) for finding global optimum for any given test functions. The procedure of the ACO algorithms simulates the decision-making processes of ant colonies as they forage for food and is similar to other artificial intelligent techniques such as Tabu search, Simulated Annealing and Genetic Algorithms. ACO algorithms can be used as a tool for optimizing continuous and discrete mathematical functions. The proposed algorithm is based on each ant searches only around the best solution of the previous iteration with β. The proposed algorithm is called as ACORSES, an abbreviation of ACO Reduced SEarch Space. β is proposed for improving ACO’s solution performance to reach global optimum fairly quickly. The ACORSES is tested on fourteen mathematical test functions taken from literature and encouraging results were obtained. The performance of ACORSES is compared with other optimization methods. The results showed that the ACORSES performs better than other optimization algorithms, available in literature in terms of minimum values of objective functions and number of iterations.  相似文献   
86.
Feng Yu  Yanjun Li  Tie-Jun Wu 《Physica A》2010,389(3):629-636
A large number of networks in the real world have a scale-free structure, and the parameters of the networks change stochastically with time. Searching for the shortest paths in a scale-free dynamic and stochastic network is not only necessary for the estimation of the statistical characteristics such as the average shortest path length of the network, but also challenges the traditional concepts related to the “shortest path” of a network and the design of path searching strategies. In this paper, the concept of shortest path is defined on the basis of a scale-free dynamic and stochastic network model, and a temporal ant colony optimization (TACO) algorithm is proposed for searching for the shortest paths in the network. The convergence and the setup for some important parameters of the TACO algorithm are discussed through theoretical analysis and computer simulations, validating the effectiveness of the proposed algorithm.  相似文献   
87.
Supply chain system is an integrated production system of a product. In the past researches, this system was often assumed to be an equilibrium structure, but in real production process, some members in this system usually cannot effectively complete their production task because of the losses of production, which will reduce the performance of the whole supply chain production system. This supply chain with the losses of production is called the defective supply chain (DSC) system. This research will discuss the partner selection and the production–distribution planning in this DSC network system. Besides the cost of production and transportation, the reliability of the structure and the unbalance of this system caused by the losses of production are considered. Then a germane mathematical programming model is developed for solving this problem. Due to the complex problem and in order to get a satisfactory near-optimal solution with great speed, this research proposes seeking the solution with the solving model based on ant colony algorithm. The application results in real cases show that the solving model presented by this research can quickly and effectively plan the most suitable type of the DSC network and decision-making of the production–distribution. Finally, a comparative numerical experiment is performed by using the proposed approach and the common single-phase ant colony algorithm (SAC) to demonstrate the performance of the proposed approach. The analysis results show that the proposed approach can outperform the SAC in partner selection and production–distribution planning for DSC network design.  相似文献   
88.
随着图像处理技术的不断发展,本文利用图像处理技术分析变电站中隔离开关的状态。蚁群算法(Ant Colony Algorithm,ACA)使用的广泛性,很多学者将其应用到图像处理中。本文将蚁群算法应用于变电站设备区域图像分割中,从某个或某些像素点出发,提取出变电站的隔离开关信息,然后对其进一步的图像处理,分析隔离开关的状态。但是,蚁群算法在运算过程中,易出现过早收敛于局部最优解及运算时间过长的缺点。为了使蚁群算法收敛于全局最优解及加快收敛速度,本文针对传统的蚁群算法模型对其信息浓度更新规则改进及参数的改进。通过仿真对比分析改进后的蚁群算法对于图像分割效果更好。  相似文献   
89.
蔡庭  黄善国  李新  尹珊  张杰  顾畹仪 《光子学报》2014,41(12):1400-1404
随着光网络规模的不断扩大以及网络体系结构的扁平化过程加速,网络传输的可靠性和实时性以及生存性路面算法本身面临新的挑战.本文在单点割集的松弛生存性约束条件下,结合动态业务下的IP over WDM光网络的特点,借助蚁群优化算法的强鲁棒性和记忆能力,通过改变与调整蚁群优化算法结构中的信息素结构与其更新机制,在动态路由选择过程中,引入网络可生存性约束信息改进路由选择概率计算机制,来实现IP over WDM光网络动态生存性映射的路由策略.与其他同类算法相比,该算法不再存储网络备用路由集和物理拓扑自身庞大的割集关系,在保证网络生存性效果的前提下,通过割集松弛条件有效降低了计算的时间复杂度,提高算法收敛速度,适应网络实时性要求.仿真结果表明:与传统最短路算法比较,该算法能有效提高动态光网络的可生存性映射性能和网络的资源利用效率,并降低业务阻塞率.  相似文献   
90.
This paper discusses the methodologies that can be used to optimize a logistic process of a supply chain described as a scheduling problem. First, a model of the system based on a real-world example is presented. Then, a new objective function called Global Expected Lateness is proposed, in order to describe multiple optimization criteria. Finally, three different optimization methodologies are proposed: a classical dispatching rule, and two soft computing techniques, Genetic Algorithms (GA) and Ant Colony Optimization (ACO). These methodologies are compared to the dispatching policy in the real-world example. The results show that dispatching heuristics are outperformed by the GA and ACO meta-heuristics. Further, it is shown that GA and ACO provide statistically identical scheduling solutions and from the optimization performance point of view, it is equivalent to use any of the meta-heuristics.  相似文献   
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