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991.
It is foreseen that more and more music objects in symbolic format and multimedia objects, such as audio, video, or lyrics,
integrated with symbolic music representation (SMR) will be published and broadcasted via the Internet. The SMRs of the flowing songs or multimedia objects will form a
music stream. Many interesting applications based on music streams, such as interactive music tutorials, distance music education, and
similar theme searching, make the research of content-based retrieval over music streams much important. We consider multiple
queries with error tolerances over music streams and address the issue of approximate matching in this environment. We propose
a novel approach to continuously process multiple queries over the music streams for finding all the music segments that are
similar to the queries. Our approach is based on the concept of n-grams, and two mechanisms are designed to reduce the heavy
computation of approximate matching. One mechanism uses the clustering of query n-grams to prune the query n-grams that are
irrelevant to the incoming data n-gram. The other mechanism records the data n-gram that matches a query n-gram as a partial
answer and incrementally merges the partial answers of the same query. We implement a prototype system for experiments in
which songs in the MIDI format are continuously broadcasted, and the user can specify musical segments as queries to monitor
the music streams. Experiment results show the effectiveness and efficiency of the proposed approach. 相似文献
992.
993.
Choosing knowledge management strategies by using a combined ANP and DEMATEL approach 总被引:4,自引:1,他引:3
Numerous companies are expecting their knowledge management (KM) to be performed effectively in order to leverage and transform the knowledge into competitive advantages. However, here raises a critical issue of how companies can better evaluate and select a favorable KM strategy prior to a successful KM implementation. The KM strategy selection is a kind of multiple criteria decision-making (MCDM) problem, which requires considering a large number of complex factors as multiple evaluation criteria. A robust MCDM method should consider the interactions among criteria. The analytic network process (ANP) is a relatively new MCDM method which can deal with all kinds of interactions systematically. Moreover, the Decision Making Trial and Evaluation Laboratory (DEMATEL) not only can convert the relations between cause and effect of criteria into a visual structural model, but also can be used as a way to handle the inner dependences within a set of criteria. Hence, this paper proposes an effective solution based on a combined ANP and DEMATEL approach to help companies that need to evaluate and select KM strategies. Additionally, an empirical study is presented to illustrate the application of the proposed method. 相似文献
994.
An atomistic-continuum inhomogeneous material model for the elastic bending of metal nanocantilevers
The equivalent elastic modulus of nanocantilever can be obtained using atomistic simulation. However, the use of this modulus to predict the bending of nanocantilever results in significant error compared with direct atomistic simulation. The error originates from the surface effect. In our current work, the nanocantilever is considered as an inhomogeneous continuum material. The distributions of materials parameters at the cross-section, such as atomistic elastic constants, are calculated from atomistic simulations. These atomistic-information-based materials parameters are used as inputs to continuum model. A numerical example case validates the presented model and methodology. To correctly predict the structure-property relations of elemental nano-structures are very important for the design of nano-devices. Our continuum model includes nano-effects and provides another way to study nanomechanics. 相似文献
995.
采用离子选择性电极和电位恒定的参比电极作为敏感头,与高输入阻抗、高精度的电位计组成传感器,以LabVIEW为开发平台的虚拟仪器,通过数据采集卡,实时在线监测水体中多种离子含量,并对数据进行整理,以消除离群数据的影响,为水质污染的在线监测提供了一种具有理论指导意义和实用价值的新方法. 相似文献
996.
Design of variable structure control for fuzzy nonlinear systems 总被引:1,自引:0,他引:1
In this paper, the variable structure control problem is presented for Takagi–Sugeno fuzzy systems with uncertainties and external disturbances. The sliding surfaces for the T–S fuzzy system are proposed by using a Lyapunov function and a fuzzy Lyapunov function, respectively. And we design the variable structure controllers such that the global T–S fuzzy system confined on the sliding surfaces is asymptotically stable. Two examples are given to illustrate the effectiveness of our proposed methods. 相似文献
997.
This paper proposes an approach to reduce the total operational cost of a spare part logistic system by appropriately designing the BOM (bill of material) configuration. A spare part may have several vendors. Parts supplied by different vendors may vary in failure rates and prices – the higher the failure rate, the lower the price. Selecting vendors for spare parts is therefore a trade-off decision. Consider a machine where the BOM is composed of s critical parts and each part has k vendors. The number of possible BOM configurations for the machine is then ks. For each BOM configuration, we can use OPUS10 (proprietary software) to calculate an optimum inventory policy and its associated total logistic cost. Exhaustively searching the solution space by OPUS10 can yield an optimal BOM configuration; however, it may be formidably time-consuming. To remedy the time-consuming problem, this research proposes a GA-neural network approach to solve the BOM configuration design problem. A neural network is developed to efficiently emulate the function of OPUS10 and a GA (genetic algorithm) is developed to quickly find a near-optimal BOM configuration. Experiment results indicate that the approach can obtain an effective BOM configuration efficiently. 相似文献
998.
首先介绍基于服务体/执行流模型的操作系统Minicore的基本特征,进而详细讨论了如何利用内核态功能实现二进制Linux应用代码的高效兼容运行方法,以及Minicore中Linux运行环境服务体设计的关键技术和解决方案,并给出了实验测试数据以说明所提出技术的有效性. 相似文献
999.
1000.
基于XML的数据交换是一种典型的Web应用,通过分析基于服务的数据交换数据,说明在该Web应用中,存在的安全问题和需求,架构一个基于PKI/PMI的安全Web数据交换平台,实现应用层的授权和安全访问控制,并应用在实际中. 相似文献