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1.
Crew rostering system is a daily grind in the management of both corporation and enterprise. A fair and reasonable rostering method plays a very important role in the arousing worker's enthusiasm and improving the work efficiency. This paper presents a method of building models for automatic crew rostering mode with computer and advancing the multi-objective optimum scheme. The method to build models for crew rostering system is also discussed. The question to crew rostering system model is solved by genetic algorithms and simulated annealing algorithms. Simulation results show the correctness of algorithms. The actual data of the airways have justified its reasonability and efficiency.  相似文献   

2.
Most of the existing text clustering algorithms overlook the fact that one document is a word sequence with semantic information. There is some important semantic information existed in the positions of words in the sequence. In this paper, a novel method named Frequent Itemset-based Clustering with Window (FICW) was proposed, which makes use of the semantic information for text clustering with a window constraint. The experimental results obtained from tests on three (hypertext) text sets show that FICW outperforms the method compared in both clustering accuracy and efficiency.  相似文献   

3.
Peer-to-Peer systems are emerging as one of the most popular Intemet applications. Structured Peer-to-Peer overlay networks use identifier based routing algorithms to allow robustness, load balancing, and distributed lookup needed in this environment. However, identifier based routing that is independent of Internet topology tends to be of low efficiency. Aimed at improving the routing efficiency, the super-proximity routing algorithms presented in this paper combine Internet topology and over|ay routing table in choosing the next hop. Experimental results showed that the algorithms greatly improve the efficiency of Peer-to-Peer routing.  相似文献   

4.
The problem of geometric non-linearity simulation for spacial cable system was solved by introducing the truss element based on corotational coordinate (CR) system, cable structure materials and node coordinates and automatic refreshing algorithms for element internal force. And the shape-finding problem for maneuvering profile was solved with the Newton-Raphson based on energy convergence criteria with search function. This has avoided the regular truss element assumption extensively used in traditional methods and catenary elements which have difficulties in practical application because of the complicated formulas. The use of CR formulation has taken into account the stiffness outside the cable plane via a geometric stiffness matrix, realizing the 3D space analysis of a cable bridge and improving the efficiency and precision for the space geometric non-linearity analysis and cable structure, and enabling more precised simulation of geometric form finding and internal force of the large span suspension bridge main cable under construction.  相似文献   

5.
The problem of scalable classification by clustering in large databases was discussed. Clustering based classification method first generates clusters using clustering algorithms. To classify new coming da-ta points, it finds the κ nearest clusters of the data point as neighbors, and assign each data point to the dominant class of these neighbors. Existing algorithms incorporated class information in making clustering decisions and produced pure clusters (each cluster associated with only one class). We presented hybrid cluster based algorithms, which produce clusters by unsupervised clustering and allow each cluster associ- ated with multiple classes. Experimental results show that hybrid cluster based algorithms outperform pure ones in both classification accuracy and training soeed.  相似文献   

6.
Several key problems in automatic layout design of spacecraft modules   总被引:2,自引:0,他引:2  
Computer-aided layout design of spacecraft modules, such as satellite modules and manned spaceship modules, is of great significance and egregious complexity. It is known as a combinatorial optimization and NPC problem in mathematics, a conceptual design and complex system in engineering. The main difficulties include representation and formulation of the problem in mathematics and the solution strategy and pragmatic approaches in engineering practice. After a brief survey of the state-of-the-art in relevant fields, this paper summarizes the research work of the authors' group on automatic layout design of spacecraft modules in the last 15 years, mainly focusing on 5 key problems. They are modeling and problem-solving algorithms, interference calculation, theory and applications of layout topological pattern, decision-making in layout design, and their pragmatic approaches in engineering practice.  相似文献   

7.
Incremental redundancy hybrid automatic repeat request (IR HARQ) has been extensively studied for reliable data transmission over slow-fading or quasi-static channels. With the increase in movement speed of users and the use of long code words for data transmission, IR HARQ strategy in fast-fading channels is starting to attract attention in the academia. This paper studies the perfor- mance of the IR HARQ strategy based on Kite codes (a class of rateless codes) in the finite regime over fast-fading channels where a number of channel realizations are experienced in each retransmission round. We propose an algorithm that exploits current decoding reliability to determine the size of subsequent retransmissions. Long- term throughput and delay constraint throughput are ana- lyzed and compared. Furthermore, in HARQ systems available, most of the computation power is consumed on failed decoding if a code word is retransmitted many times, which is not energy-efficient. Therefore, to improve theenergy efficiency, we propose two efficient algorithms (early stopping algorithm and freezing node algorithm) for incremental decoding, which reduce the computational complexity of the most time-consuming steps in decoding procedure. Simulation results show that the substantial complexity reduction is achieved in terms of the total required number of decoding iterations and the required node operation complexity compared to conventional incremental decoding scheme.  相似文献   

8.
At present, how to enable Search Engine to construct user personal interest model initially, master user's personalized information timely and provide personalized services accurately have become the hotspot in the research of Search Engine area. Aiming at the problems of user model's construction and combining techniques of manual customization modeling and automatic analytical modeling, a User Interest Model (UIM) is proposed in the paper. On the basis of it, the corresponding establishment and update algorithms of User lnterest Profile (UIP) are presented subsequently. Simulation tests proved that the UIM proposed and corresponding algorithms could enhance the retrieval precision effectively and have superior adaptability.  相似文献   

9.
With the growing popularity of Internet applications and the widespread use of mobile Internet, Internet traffic has maintained rapid growth over the past two decades. Internet Traffic Archival Systems(ITAS) for packets or flow records have become more and more widely used in network monitoring, network troubleshooting, and user behavior and experience analysis. Among the three key technologies in ITAS, we focus on bitmap index compression algorithm and give a detailed survey in this paper. The current state-of-the-art bitmap index encoding schemes include: BBC, WAH, PLWAH, EWAH, PWAH, CONCISE, COMPAX, VLC, DF-WAH, and VAL-WAH. Based on differences in segmentation, chunking, merge compress, and Near Identical(NI) features, we provide a thorough categorization of the state-of-the-art bitmap index compression algorithms. We also propose some new bitmap index encoding algorithms, such as SECOMPAX, ICX, MASC, and PLWAH+, and present the state diagrams for their encoding algorithms. We then evaluate their CPU and GPU implementations with a real Internet trace from CAIDA. Finally, we summarize and discuss the future direction of bitmap index compression algorithms. Beyond the application in network security and network forensic, bitmap index compression with faster bitwise-logical operations and reduced search space is widely used in analysis in genome data, geographical information system, graph databases, image retrieval, Internet of things, etc. It is expected that bitmap index compression will thrive and be prosperous again in Big Data era since 1980s.  相似文献   

10.
An integrated self-healing algorithm for resilient packet ring   总被引:1,自引:0,他引:1  
Resilient Packet Ring (RPR) is a Media Access Control (MAC) layer protocol that operates over a double counter-rotating ring network topology. RPR is designed to enhance Synchronous Digital Hierarchy (SDH) in order to handle data traffic more efficiently. Since Intelligent Protection Switching (IPS) is one of the key technologies in ring networks, RPR provides two intelligent protection algorithms: steering and wrapping. While wrapping in RPR in essence inherits the automatic protection switching (APS) algorithm of SDH, it also wastes the bandwidth on the wrapping ringlets and may result in severe congestion. Whereas steering in RPR provides high bandwidth utilization, its switching speed is low, because it is indeed a high layer's restoration algorithm. In this paper, integrated self-healing(ISH) algorithm as an effective algorithm for RPR is proposed, which synthesizes the merits of the two algorithms by transporting healing signal and computing routing in MAC layer. At last, the performance of ISH algorithm is analyzed and simulated.  相似文献   

11.
自动生成决策树的通用算法模板   总被引:4,自引:0,他引:4  
目的 提供自动生成决策树的通用算法模板,从而使算法的设计能够快速验证为解决特定决策问题而设计的新算法。方法 提供智能编辑器供算法设计定义自己的公式,并利用该公式或内置算示来初始化通用算法模板,从而实现连续属性的离散化、采用基于概率分布的方法处理未知属性和噪声数据,利用预剪枝和后剪枝算法进行剪枝。结果与结论 用户能够利用该模板,在系统提供的交互式图形环境中,针对不同的决策问题测试决策树生成算法。  相似文献   

12.
本文讨论了在微机中西文表格自动处理技术中一些特殊功能的算法设计,分析了设计思想,提供了部份实用算法,并对某些算法的时间复杂度进行了评述。这些算法均已在本校研制的“IBM-PC/XT微型机中西文数据库管理系统”的表格自动处理软件中实现,并已应用于百多家企、事业单位的计算机管理系统中。  相似文献   

13.
计算机光学乐谱识别(OpticalMusicRecognition,OMR)利用扫描仪等数码设备,对已有的纸质乐谱进行扫描,形成数字乐谱图像,再利用专用的软件系统进行处理与识别,提取出音乐信息.文章根据乐谱中音乐符号的统计与结构特征,提出了方向数的概念,并构造出方向数探测法,利用此方法对倾斜数字乐谱图像进行谱线、小节线和符干的识别,通过对50例乐谱的试验,取得较好的效果.  相似文献   

14.
《清华大学学报》2020,25(5):553-563
Learning With Errors (LWE) is one of the Non-Polynomial (NP)-hard problems applied in cryptographic primitives against quantum attacks.However,the security and efficiency of schemes based on LWE are closely affected by the error sampling algorithms.The existing pseudo-random sampling methods potentially have security leaks that can fundamentally influence the security levels of previous cryptographic primitives.Given that these primitives are proved semantically secure,directly deducing the influences caused by leaks of sampling algorithms may be difficult.Thus,we attempt to use the attack model based on automatic learning system to identify and evaluate the practical security level of a cryptographic primitive that is semantically proved secure in indistinguishable security models.In this paper,we first analyzed the existing major sampling algorithms in terms of their security and efficiency.Then,concentrating on the Indistinguishability under Chosen-Plaintext Attack (IND-CPA) security model,we realized the new attack model based on the automatic learning system.The experimental data demonstrates that the sampling algorithms perform a key role in LWE-based schemes with significant disturbance of the attack advantages,which may potentially compromise security considerably.Moreover,our attack model is achievable with acceptable time and memory costs.  相似文献   

15.
在传统的地震资料解释或速度分析等过程中,通常都是依靠人工识别与拾取,不但工作量大,而且效率非常低。因此,工业界开始使用各种算法来进行地震同相轴的自动识别与拾取,但是这些算法存在较多的缺陷,精度不高。地震剖面可视为由地震子波与反射系数褶积构成,子波以及噪音的存在对剖面的自动拾取带来一定困难。通过对地震子波进行特征抽取,并将地震剖面进行稀疏化表达,降低子波以及噪音对自动拾取的影响,同时减少数据采样点数,提高计算效率。通过引入矢量距离,并结合动态波形匹配算法计算特征化矢量数据的最小距离,从而实现同相轴的自动追踪。理论资料测试证明方法的正确性和抗噪能力,东部某探区实际资料自动拾取证明了论文方法的有效性。  相似文献   

16.
一种新型的遗传算法在图象阈值处理中的应用   总被引:1,自引:0,他引:1  
提出了将自寻优标准遗传算法用于阈值处理的思路与方法,论证了实施该方法的可行性,并针对此算法的不足之处提出了一种新的改进型遗传算法。仿真结果表明,新算法的计算速度不仅明显优于前者,而且为自动选择阈值参数提供了简单有效的方法。  相似文献   

17.
18.
针对分布式随机迭代系统的特点,运用离散随机大系统的稳定性分析方法,提出一种易于作自动推理的分布式随机迭代系统稳定性并行分析法;解决了具有分布结构的随机迭代系统中出现的Lyapunov方程的高效并行算法问题.  相似文献   

19.
为了有效利用电能质量复合扰动识别中存在的大量难以标注的实测样本,提出了一种基于Jerk流形正则化深度极限学习机(DJRELM)的半监督扰动学习方法. 算法通过堆叠嵌入Jerk流形正则化的极限学习机自编码器(JRELM-AE)实现在复合扰动特征自动提取的同时保持数据内部流形结构. 分类层通过阈值预测极限学习机和Jerk正则化半监督极限学习机的结合将多层网络扩展到多标签半监督分类应用. 实验结果表明:该方法在不同噪声环境下的分类准确率均高于几种基于极限学习机的监督学习、半监督学习算法、传统多层极限学习机和深度卷积神经网络,具有理论意义和实用价值.  相似文献   

20.
计算机自动查重程序的算法分析   总被引:3,自引:0,他引:3  
主要介绍了香港浸会大学图书馆于 2 0 0 1年自行开发计算机自动查重程序 ,以完全自动化方法 ,取代耗时费力的传统人工采访查重及馆藏评价的书目核对工序  相似文献   

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