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It is very important to optimize pattern design of ETL scenario's to data warehouse's integration in the ETL (extract-transformation-load) tools development, a good modeling process is helpful to the accuracy of description in data source, and makes the ETL workflow's design more reasonable. To find out a methodology for facilitating the modeling and management of ETL processes, aimed at Alkis Simitsis...
On the base of NS-IMMC, this paper propose a new method of generating the cause-and-effect of news topic. The new method choose representative sentences for news documents according to the specialty of news structure (NS, News structure), and then utilizes IMMC (Improved Min-Max clustering) to classify these representative sentences to generate multi-documents summary which represents the topic cause-and-effect...
In recent years, the research of role-based access control model has been emphasized.The Spatial Role-Based Access Control (SRBAC) model is the expansion of spatial character in RBAC96. SRBAC has more comprehensive, more specific description of the system's security. Based on SRBAC, this paper focuses on the session character. Formal definition of SRBAC Model was put forward at first. And then, different...
Suppose that x1, y1, x2 and y2 are four integers. For a given Cayley digraph Omega=Cay(G, {a, b}), where G=Z2/K, a=(1, 0)+K, b=(0, 1)+K, K=<alpha, beta>, alpha=(x1, y2), beta=(x2, y2), an algorithm is given to compute the four parameters l, h, m, n of its L-shape tile. Thus the diameter of this Cayley digraph can be calculated by d(Omega)=max{l+h-m-2, l+h-n-2}.
Enterprise now urgently expects to utilize its proliferating unstructured information resources to improve its competitive capability. In order to manage unstructured information resources effectively, some kinds of technologies, such as natural language processing, intellectualized text analyzing, knowledge management and so on, should been synthetically applied and some especial demands, such as...
This paper introduces the continuous chaotic frequency modulation signals (CCFMS), which have good autocorrelations and flat frequency spectra. We show that the CCFMS have excellent delay and velocity detection performance. Moreover, the CCFMS require far lower realization costs and can provide flexible parameters adjustment. Simulation results show that the delay resolution of the CCFMS can be improved...
To avoid it happening that the correctness of created model and developed simulation software on calculating the response time of ABS (anti-lock brake system) is partially verified by the experiment result, based on the structure of a typical ABS, the calculation models of the controllable characteristic and mechanical characteristic were created, and the simulation calculation software was developed...
Model driven development is an approach that using modeling languages such as UML or BON to establish requirement models for the complementary of software specification, as well as for further implementation. How ever, a model of a complex systems is always consist of multiple views, such as static views and dynamic views to describe different perspectives of the system, thus may cause inconsistency...
This paper presents a method based on information entropy to analyze the capacity of covert channels. Built upon noninterference, the method is firstly used to calculate the covert channel capacity, then to analyze the factors that have an impact on this quantity. Finally an example is given of the capacity calculation for covert channels in a multilevel secure database.
There are the selfish and malicious nodes that two types of threats exist in ad hoc network. This paper gives the detailed analysis of the two types of threats, introduces some existing solutions and point out their inadequacy at the same time. On this basis, a solution based on trust evaluation was proposed.
In the problem of multiple criteria decision making, there are situations in which information is incomplete or imprecise or views that are subjective or endowed with linguistic characteristics creating a "fuzzy" decision making environment, some index can't be expressed by certain number, just only expressed by linguistic words, under this situation, we must use fuzzy decision making method...
Information systems' centralizing is an inevitable direction. To solve the problem that enterprise users could remotely and securely share software resources in data center, a secure access platform (SAP) based on remote desktop protocol (RDP) was proposed. According to the characteristics of software resources sharing, the software resources sharing model (SRSM) and the secure access platform model...
The medical image registration has been all confined in registering two images and rarely involved multiple images (three and more than three). Using the expanded mutual information measure (E-MIM) to register multiple images, which is inefficiency, can't meet the clinical requirement, and mutual information (MI) values are not necessarily nonnegative. In this paper, we introduce an N-dimensional...
With the incorporation and globalization of financial market, the dependence relation between financial time series is strengthening, especially when the extreme events occur, the dependence effect is more obvious. Itpsilas very interesting to investigate the dependence structure and measures of tail part of time series. In this paper, some dependence probabilities and conditional tail-dependence...
In mobile ad hoc networks (MANETs), a single certificate authority (CA) node could be a security bottleneck. Multiple replica of CA is fault tolerant, but the network is as vulnerable as single CA or even worse since breaking one of the CAs means breaking all of them. Many distributed CA models based on the secret sharing scheme are proposed. In this paper, the suitable construction of the distributed...
Controller synthesis uses hardware description language and synthesis optimization tools from a higher abstract level. State transition graph of completely specified finite state machine is adopted to describe the behavior of controller. State transition graph STG_org was generated before synthesized and state transition graph STG_ext was reversely extracted from structure realization of controller...
The aliasing probability in single and multiple input Linear Automata Signature Registers has been widely studied under the independent bit error model. This paper examines aliasing in a class of Multiple-input Signature Registers (MISR), under the q-ary symmetric error model. By modeling the signature analyzer as two-state Markov process and four-state Markov process, we derived the close aliasing...
In this paper, a genetic accelerated trust region algorithm without constraints presented, which can deviate saddle point, and quickly reach more excellent point by using probabilistic optimization approach. While trust region algorithm can only converge to partial optimum, the new algorithm can converge to global optimum with an example proved the validity.
There are some disadvantage in traditional "special line" networking, IP network, frame relay and the ATM network. A VPN networking project which based on MPLS is put forward in order to solve the problem. Then analyze the realization of MPLS VPN. The simulation principle, simulation process and simulation scenes are introduced by OPNET, get the results that MPLS VPN has lower delay and...
The total variation flow is used to construct image nonlinear scale space by its structure preserved characteristics. The concept of divergence used in this model is mainly based on image gradient which is often computed in one order neighbor. This restricts the selection of scale parameters so that only diffusion time and weight of fidelity function can be used. Actually, the common sense of spatial...
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