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81.
冯家团 《中国水能及电气化》2013,(5)
水利工程概算编制是工程设计的重要组成部分,对于合理确定工程造价预算、确保有效控制工程项目投资规模、合理使用投资、提高投资回报率,是必不可少的.本文简要归纳了一些普遍存在于水利工程设计概算编制中的问题,并结合工程实际提出了几项应对措施,以期提升设计概算编制的质量、保证项目投资控制目标的实现,从而取得较好的投资效益和社会效益. 相似文献
82.
针对线性规划问题,文中引入了一种与传统障碍函数不同的新的障碍函数,其在可行域边界上的取值是有限的.沿此有限障碍函数所确定的新的搜索方向,给出了短步长全牛顿步内点算法,结果证明该算法具有目前求解线性规划问题最好的复杂性界. 相似文献
83.
In this paper, we propose an efficient Tabu Search procedure for solving the NP-hard network pricing problem. By exploiting the problem's features, the algorithm allows the near-optimal solution of problem instances that are out of reach of exact combinatorial methods. 相似文献
84.
K. VivekanandanAuthor Vitae D. RamyachitraAuthor Vitae 《Future Generation Computer Systems》2012,28(4):647-656
Scientific applications such as protein sequence analysis require a coordination of resources. This is due to hundreds and hundreds of protein sequences being deposited into data banks by the research community which results in an extensive database search when one wants to find a similar protein sequence. This search becomes easier and the time taken is reduced when it is conducted in a grid environment implemented using the Globus tool kit. This paper proposes the use of Bacteria Foraging Optimization (BFO) for finding similar protein sequences in the existing databases. Usage of BFO further reduces the time taken by a resource to execute the user’s requests. Also, the resources utilized in the proposed method are better balanced compared to the existing scheduling algorithms. Also, it is found that the number of tasks executed is more compared to the existing algorithms even though there is a fall in the execution of tasks as the number of resources increases which might be due to network failure etc. The proposed BFO has been compared with the existing First Come First Serve (FCFS) and Minimum Execution Time (MET) scheduling algorithms and it has been found that the proposed BFO performs well compared to the existing algorithms in terms of makespan, resource utilization and minimization in the case of non-execution of client requests. 相似文献
85.
86.
茹莉 《黄河水利职业技术学院学报》2013,(3):81-84
分析了影响对外汉语专业毕业生就业的各种因素,主张以积极的心态看待就业形势,正视存在的问题,加强专业建设,优化课程设置,落实实践环节,提升专业素质和求职技能,以提高对外汉语专业学生就业率和就业质量。 相似文献
87.
88.
针对ESO参数不易整定的问题,研究了扩张状态观测器(ESO)参数优化的李雅普诺夫函数法.首先建立关于误差的线性定常状态方程和误差指标函数J,在误差指标函数J中综合考虑了跟踪误差的权重和系统的稳定性以及实际运行时的饱和值限制等因素.仿真结果表明,此方法具有概念清晰,实用简便,计算量小的优点.所提ESO参数整定方法是有效的. 相似文献
89.
Ant colony optimization (ACO) is a metaheuristic approach for combinatorial optimization problems. With the introduction of hypercube framework, invariance property of ACO algorithms draws more attention. In this paper, we propose a novel two-stage updating pheromone for invariant ant colony optimization (TSIACO) algorithm. Compared with standard ACO algorithms, TSIACO algorithm uses solution order other than solution itself as independent variable for quality function. In addition, the pheromone trail is updated with two stages: in one stage, the first r iterative optimal solutions are employed to enhance search capability, and in another stage, only optimal solution is used to accelerate the speed of convergence. And besides, the pheromone value is limited to an interval. We prove that TSIACO not only has the property of linear transformational invariance but also has translational invariance. We also prove that the pheromone trail can limit to the interval (0, 1]. Computational results on the traveling salesman problem show the effectiveness of TSIACO algorithm. 相似文献
90.
The drawbacks of SVD-based image watermarking are false positive, robust and transparency. The former can be overcome by embedding the principal components of the watermark into the host image, the latter is dependent on how much the quantity (i.e., scaling factor) of the principal components is embedded. For the existing methods, the scaling factor is a fixed value; actually, it is image-dependent. Different watermarks need the different scaling factors, although they are embedded in the same host image. In this paper, two methods are proposed to improve the reliability and robustness. To improve the reliability, for the first method, the principal components of the watermark are embedded into the host image in discrete cosine transform (DCT); and for the second method, those are embedded into the host image in discrete wavelets transform (DWT). To improve the robustness, the particle swarm optimization (PSO) is used for finding the suitable scaling factors. The experimental results demonstrate that the performance of the proposed methods outperforms than those of the existing methods. 相似文献