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1.
树排序算法是堆排序算法的变体,本文给出了逻辑堆的结构并将其应用于树排序算法中使得树排序算法的最坏复杂度由原来的4nlogn+O(n)降低到2nlogn+O(nloglogn)+O(n),接近于最优堆排序算法(复杂度为nlogn+nloglogn+O(n),并且对几乎已有序的输入,算法的复杂度为O(nloglogn),这在n<218的实际应用中基本保持了原树排序算法的优势.  相似文献   

2.
本文给出处理机具有不同的开始加工时间的Q,ai|pmitn|Cmax排序问题的一个最优算法,算法的复杂性为O(m^2n^2)。  相似文献   

3.
本文对n个任务,2台同类处理机的排序问题Q2∥Cmax进行讨论,提出一个算法,用该算法得到的排序表长的界是2b+1/2bM,算法的复杂性为O(nlogn)。  相似文献   

4.
本文对n个任务,2台同类处理机的排序问题Q2||Cmax进行讨论,提出一个算法.用该算法得到的排序表长的界是2b+12bM*.算法的复杂性为O(nlogn).  相似文献   

5.
本文提出一种在SIMD-EREW计算模型上实现的并行排序算法。算法采用基数交换排序方法,在处理过程中无存贮访问冲突。对长度为n的序列,算法使用不超过n/2个处理单元,时间复杂度为O(u.log2n),其中u为不超过处理器字长的常数。该算法适合于具有较多重复元素的序列排序。  相似文献   

6.
针对外排序存在的困难,给出了一种高效的外排序方法.利用分段的思想将内、外排序算法结合起来,减少计算过程中读写外存的次数,从而提高速度和效率,算法复杂性为O(nlog2n),通常数百万的排序数据仅需读写磁盘二三遍便可完成排序,大大地减少读写磁盘遍数.本算法既适合内排序,也适合外排序  相似文献   

7.
本文提出一种在SIMD-EREW计算模型上实现的并行排序算法.算法采用基数交换排序方法,在处理过程中无存贮访问冲突.对长度为n的序列,算法使用不超过个处理单元,时间复杂度为O(u.log2n),其中u为不超过处理器字长的常数.该算法适合于具有较多重复元素的序列排序.  相似文献   

8.
工序问题的动态规划算法   总被引:1,自引:0,他引:1  
提出了一个求解工序问题的动态规划算法,该算法排序含n个工件集合的期望时间为O(n).  相似文献   

9.
在搜索技术和各种流行的排序算法优缺点比较的基础上,给出了一种基于后缀数组的新的快速排序算法,该算法在时间和空间性能上均优于传统的快速排序算法;并在同等的条件下,用该方法与快速排序算法对相同的内容进行排序,结果表明:该算法特别适用于大文本的排序问题,可用于搜索技术和数据压缩中.  相似文献   

10.
二分搜索法是利用了元素组已排序的性质的一种效率较高的元素定位方法,具有编程简单且易于计算机实现等特点,将此算法应用于数组的排序中可提高数组排序的效率。  相似文献   

11.
In this paper we discuss a parallel sorting algorithm on a hypercube. Its time complexity isO(n logn/p) +O(n). Here,P is the number of processors avaliable and n, the amount of items to be sorted. Take the problem of time-space optimization into consideration, whenPO(logn), this algorithm is both time-space optimal and cost optimization. But this means only speedup isO(p) and it is not linear speedup. Therefore, we further discuss relevant parallel efficiency problems.  相似文献   

12.
In this paper, a new broadcast encryption scheme is proposed by using the efficient and computationally inexpensive public key cryptosystem NTRU (number theory research unit). In our scheme, we use the idea of RSA and develop this idea from two-party to multi-party, and combine this multi-party public key idea with the multiplication in ring R of NTRU. What we get from this design is extremely efficient encryption and decryption, fast and easy key creation, low memory requirements and revocation property, etc. Moreover, this novel work contains other desirable features, such as traitor tracing. With its complexity only O(log2 n), the tracing algorithm of this system is more efficient than that of the previous ones.  相似文献   

13.
In view of the fact that the problem of sorting unsigned permutation by reversal is NP-hard, while the problem of sorting signed permutation by reversal can be solved easily, in this paper, we first transform an unsigned permutation of length n,π (π1 ,… ,πn), into a set S(π) containing 2^n signed permutations, so that the reversal distance of π is equal to the reversal distance of the optimal signed permutation in S(π). Then analyze the structural features of S(π) by creating a directed graph and induce a new computing model of this question. Finally, an improved genetic algorithm for solving the new model is proposed. Experimental results show that the proposed model and algorithm is very efficient in practice.  相似文献   

14.
何登旭  戴祯杰 《广西科学》1999,6(3):174-176
给出符号差类运输问题的一个多项式时间算法,并证明该算法的时间复杂性是O(mn^2+m^2n)。  相似文献   

15.
免授权大规模机器类通信(massive machine-type communication, mMTC)系统上行链路面临低分辨率量化、相关衰落信道以及机器类设备(machine-type device,MTD)活跃概率未知等实际挑战。针对上述问题,引入广义期望一致性(generalized expectation consistent, GEC)算法,然而GEC算法涉及高维矩阵求逆,其复杂度高达O(N3),其中N为MTD数量。结合Woodbury公式与诺曼级数近似,并利用发射数据帧的结构稀疏性,提出了一种基于多测量矢量的近似广义期望一致性(approximate generalized expectation consistent multiple measurement vector, AGEC-MMV)算法,在mMTC系统中(基站天线数量M),该算法能够规避GEC中的高维矩阵求逆,使其复杂度由O(N3)降至O(N2M)。仿真结果表明,所提AGEC-MMV算法能以较低复杂度取得接近GEC算法的性能,且在鲁棒性方面优于现有先进算法。  相似文献   

16.
令S(n)为Smarandache函数,SL(n)为SmarandacheLCM函数,φ_2(n)为广义欧拉函数。讨论方程S(SL(n~(14)))=φ_2(n)和S(SL(n~(36)))=φ_2(n)可解性,利用初等方法并结合函数φ_2(n)与函数S(n)的性质,给出了这两个方程的所有正整数解。  相似文献   

17.
以甘氨酸(Gly)和磷钨酸为原料合成的一系列无机有机杂化材料为催化剂,考察各因素对其催化合成乙酸异戊酯的影响,并利用响应面分析法优化乙酸异戊酯合成工艺。研究表明,[GlyH]_(1.0)-H_(2.0)PW_(12)O_(40)催化剂具有最高的催化酯化反应活性和重复使用性能。响应面分析法优化乙酸异戊酯合成的最佳条件为:醇酸摩尔数比为1.05∶1,催化剂用量为酸质量的4.5%,反应时间2.0h,带水剂量10mL,该条件下,乙酸异戊酯产率为98.5%,结果与模型预测值基本相符。优化条件下[GlyH]_(1.0)-H_(2.0)PW_(12)O_(40)催化酯化反应表观活化能为79.73kJ/mol。  相似文献   

18.
In Zhang's recent works,a second-order Mehrotra-type predictor-corrector algorithm for linear optimization was extended to semidefinite optimization and derived that the algorithm for semidefinite optimization had O(n~(3/2)log(X~0)~T·S~0/ε) iteration complexity based on the NT direction as Newton search direction. In this paper, we extend the second-order Mehrotra-type predictor-corrector algorithm for linear optimization to semidefinite optimization and discuss the polynomial convergence of the algorithm by modifying the corrector direction and new iterates. It is proved that the iteration complexity is reduced to O(n~(3/2)log(X~0)~T·S~0/ε), which coincides with the currently best iteration bound of Mehrotra-type predictor-corrector algorithm for semidefinite optimization.  相似文献   

19.
探讨局部扭曲立方体LTQ_n通信模式在一维阵列波分复用光网络中的路由与波长分配问题.首先通过LTQ_n的最大导出子图得到拥塞,即所需要的最少波长数;其次给出一个路由与波长分配策略,从而证明了最优波长数为2~(n+1)/3.  相似文献   

20.
In this paper,an exponential inequality for weighted sums of identically distributed NOD (negatively orthant dependent) random variables is established,by which we obtain the almost sure convergence rate of which reaches the available one for independent random variables in terms of Berstein type inequality. As application,we obtain the relevant exponential inequality for Priestley-Chao estimator of nonparametric regression estimate under NOD samples,from which the strong consistency rate is also obtained.  相似文献   

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