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1.
A vision based query interface annotation meth od is used to relate attributes and form elements in form based web query interfaces, this method can reach accuracy of 82%. And a user participation method is used to tune the result; user can answer "yes" or "no" for existing annotations, or manually annotate form elements. Mass feedback is added to the annotation algorithm to produce more accurate result. By this approach, query interface annotation can reach a perfect accuracy.  相似文献   

2.
One-dimensional carbon nano-materials (ODCNMs) synthesized from ethanol flames exhibit various agglomerated morphologies, such as "chrysanthemum-like", "hairball-like" or "orange-peel-like", "vertically aligned" and "wrinkling-pileup". The present work studied the agglomerating process and the growth mechanism by using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). It is thought that the size and distribution of the catalyst particles produced from pretreatment of the substrates play a key role during the formation of agglomerations. It is expected that the steady growth of ODCNMs in flames will be improved through the preparation of the catalysts.  相似文献   

3.
To alleviate the scalability problem caused by the increasing Web using and changing users' interests, this paper presents a novel Web Usage Mining algorithm-Incremental Web Usage Mining algorithm based on Active Ant Colony Clustering. Firstly, an active movement strategy about direction selection and speed, different with the positive strategy employed by other Ant Colony Clustering algorithms, is proposed to construct an Active Ant Colony Clustering algorithm, which avoid the idle and "flying over the plane" moving phenomenon, effectively improve the quality and speed of clustering on large dataset. Then a mechanism of decomposing clusters based on above methods is introduced to form new clusters when users' interests change. Empirical studies on a real Web dataset show the active ant colony clustering algorithm has better performance than the previous algorithms, and the incremental approach based on the proposed mechanism can efficiently implement incremental Web usage mining.  相似文献   

4.
5.
This paper presents a lighter protocol, and it removes the multicast burdens from RSVP to adapt to unicast applications. At the same time, when RSVP is used in wireless networks, some issues about mobility raise popular concerns. The proposed protocol a lightweight mobile RSVP protocol, solves the problems by the following mechanisms: changeless flow identifier, a new state management and "refresh" mechanism.  相似文献   

6.
A family of binary sequences were constructed by using an elliptic curve and its twisted curves over finite fields. It was shown that these sequences possess "good" cryptographie properties of 0-1 distribution, long period and large linear complexity. The results indicate that such se quences provide strong potential applications in cryptography.  相似文献   

7.
Building Intrusion Tolerant Software System   总被引:1,自引:0,他引:1  
In this paper, we describe and analyze the hypothesis about intrusion tolerance software system, so that it can provide an intended server capability and deal with the impacts caused by the intruder exploiting the inherent security vulnerabilities. We present some intrusion tolerance technology by exploiting N-version module threshold method in con-structing multilevel secure software architecture, by detecting with hash value, by placing an ““““““““antigen““““““““ word next to the return address on the stack that is similar to human immune system, and by adding ““““““““Honey code““““““““ nonfunctional code to disturb intruder, so that the security and the availability of the software system are ensured.  相似文献   

8.
Focused crawlers are important tools to support applications such as specialized Web portals, online searching, and Web search engines. A topic driven crawler chooses the best URLs and relevant pages to pursue during Web crawling. It is difficult to deal with irrelevant pages. This paper presents a novel focused crawler framework. In our focused crawler, we propose a method to overcome some of the limitations of dealing with the irrelevant pages. We also introduce the implementation of our focused crawler and present some important metrics and an evaluation function for ranking pages relevance. The experimental result shows that our crawler can obtain more "important" pages and has a high precision and recall value.  相似文献   

9.
A novel image hiding method based on the correlation analysis of bit plane is described in this paper. Firstly, based on the correlation analysis, different bit plane of a secret image is hided in different bit plane of several different open images. And then a new hiding image is acquired by a nesting "Exclusive-OR" operation on those images obtained from the first step. At last, by employing image fusion technique, the final hiding result is achieved. The experimental result shows that the method proposed in this paper is effec rive.  相似文献   

10.
This paper presents a novel probability generation algorithm to predict attacks from an insider who exploits known system vulnerabilities through executing authorized operations. It is different from most intrusion detection systems (IDSs) because these IDSs are inefficient to resolve threat from authorized insiders. To deter cracker activities, this paper introduces an improved structure of augmented attack tree and a notion of "minimal attack tree", and proposes a new generation algorithm of minimal attack tree. We can provide a quantitative approach to help system administrators make sound decision.  相似文献   

11.
The demand for individualized teaching from Elearning websites is rapidly increasing due to the huge differences existed among Web learners. A method for clusteringWeb learners based on rough set is proposed. The basic ideaof the method is to reduce the learning auributes prior to clustering, and therefore the clustering of Web learners iscarried out in a relative low-dimensional space. Using thismethod, the E-learning websites can arrange correspondingleaching content for different clusters of learners so that thelearners‘ individual requirements can be more satisfied.  相似文献   

12.
Multi-objective optimization is a new focus of evolutionary computation research. This paper puts forward a new algorithm, which can not only converge quickly, but also keep diversity among population efficiently, in order to find the Pareto-optimal set. This new algorithm replaces the worst individual with a newly-created one by “multi-parent crossover”. so that the population could converge near the true Pareto-optimal solutions in the end. At the same time, this new algorithm adopts niching and fitness-sharing techniques to keep the population in a good distribution. Numerical experiments show that the algorithm is rather effective in solving some Benchmarks. No matter whether the Pareto front of problems is convex or non-convex, continuous or discontinuous, and the problems are with constraints or not, the program turns out to do well. Foundation item: Supported by the National Natural Science Foundation of China(60133010, 60073043, 70071042) Biography: Chen Wen-ping ( 1977-), female, Master candidate, research direction: evolutionary computation.  相似文献   

13.
The mid-long term hydrology forecasting is one of most challenging problems in hydrological studies. This paper proposes an efficient dynamical system prediction model using evolutionary computation techniques. The new model overcomes some disadvantages of conventional hydrology forecasting ones. The observed data is divided into two parts: the slow “smooth and steady” data, and the fast “coarse and fluctuation” data. Under thedivide and conquer strategy, the behavior of smooth data is modeled by ordinary differential equations based on evolutionary modeling, and that of the coarse data is modeled using gray correlative forecasting method. Our model is verified on the test data of the mid-long term hydrology forecast in the northeast region of China. The experimental results show that the model is superior to gray system prediction model (GSPM). Foundation item: Supported by the National Natural Science Foundation of China ( 60133010, 70071042, 60073043) Biography: Zou Xiu-fen(1966-),female,Associate professor, research direction:evolutionary computing, parallel computing.  相似文献   

14.
This paper presents an effective clustering mode and a novel clustering result evaluating mode. Clustering mode has two limited integral parameters. Evaluating mode evaluates clustering results and gives each a mark. The higher mark the clustering result gains, the higher quality it has. By organizing two modes in different ways, we can build two clustering algorithms: SECDU(Self-Expanded Clustering Algorithm based on Density Units) and SECDUF(Self-Expanded Clustering Algorithm Based on Density Units with Evaluation Feedback Section). SECDU enumerates all value pairs of two parameters of clustering mode to process data set repeatedly and evaluates every clustering result by evaluating mode. Then SECDU output the clustering result that has the highest evaluating mark among all the ones. By applying "hill-climbing algorithm", SECDUF improves clustering efficiency greatly. Data sets that have different distribution features can be well adapted to both algorithms. SECDU and SECDUF can output high-quality clustering results. SECDUF tunes parameters of clustering mode automatically and no man's action involves through the whole process. In addition, SECDUF has a high clustering performance.  相似文献   

15.
This paper introduces an RTP-packets‘ loss recovery scheme in MPEG-4 playback type multicast application model, which is based on retransmission scheme. Through the auxiliary and coordinated buffer playing scheme of layered “buffer-routers”, the RTP-packets‘ loss recovery in limited time is made possible. We consider in the scheme to handle retransmission request with buffer waiting when network congestion occurs. Thus, neither the degree of congestion will be worsened nor the retransmission request will be lost when sending the request to higherlevel buffer router. The RTP-packets‘ loss recovery scheme suggested by us is not only applied to MPEG-4 muhieast application in LAN, but also can be extended to more spacious WAN (wide area network) when user groups comparatively centralize in certain number of local areas.  相似文献   

16.
Because data warehouse is frequently changing, incremental data leads to old knowledge which is mined formerly unavailable. In order to maintain the discovered knowledge and patterns dynamically, this study presents a novel algorithm updating for global frequent patterns-IPARUC. A rapid clustering method is introduced to divide database into n parts in IPARUC firstly, where the data are similar in the same part. Then, the nodes in the tree are adjusted dynamically in inserting process by "pruning and laying back" to keep the frequency descending order so that they can be shared to approaching optimization. Finally local frequent itemsets mined from each local dataset are merged into global frequent itemsets. The results of experimental study are very encouraging. It is obvious from experiment that IPARUC is more effective and efficient than other two contrastive methods. Furthermore, there is significant application potential to a prototype of Web log Analyzer in web usage mining that can help us to discover useful knowledge effectively, even help managers making decision.  相似文献   

17.
Focusing on the 18 counties along ““““One River and Two Tributaries““““ region, and based on the data from China 3^nd , 4th and 5^th population censuses, this article has analyzed the time and spatial changing patterns of the population in this region, The analyses show that since the 3^al population census, total population, average age and total birth rate have all changed considerably: ① Total population has grown fast, with most counties‘ annual average growth rate of more than 10. ② In terms of the region‘s average age, in 2000 the age inthe 18 counties is younger than 30 years old. ③ Compared with the 3^rd population census, labor force by the 5^th census is much younger. ④ Countermeasures are proposed to control population by controlling birth rate as the result of the local resident‘s quality improvement by education.  相似文献   

18.
Introduce a method of generation of new units within a cluster and a algorithm of generating new clusters. The model automatically builds up its dynamically growing in ternal representation structure during the learning process. Comparing model with other typical classification algorithm such as the Kohonen‘s self-organizing map. the model realizes a multilevel classification of the input pattern with an optional accuracy and gives a strong support possibility for the parallel computational main processor. The idea is suitable for the high-level storage of complex datas structures for object recognition.  相似文献   

19.
In this paper, an efficient hybrid proxy re-encryption scheme that allows the transformation of the ciphertexts in a traditional public key cryptosystem into the ciphertexts in an identity-based system is proposed. The scheme is non-interactive, unidirectional and collude "safe". Furthermore, it is compatible with current IBE (identity-based encryption) deployments. The scheme has chosen ciphertext security in the random oracle model assuming the hardness of the Decisional Bilinear Diffie-Hellman problem.  相似文献   

20.
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