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Astronomy is an observation-based discipline which can obtain the important information about target stars by their spectrum. The two-dimensional fiber spectra contains abundant astrophysical information which plays an important role in the digital sky survey. But, the source observed data must be processed by several procedures before being used by astronomers, and spectra extraction is one of the important procedures. Meanwhile, it is well known that all images contain inherent uncertainty information, and fuzzy set theory is a powerful tool to describe and process such uncertainty, fuzzy regression is one of the important research topics which is used to set up the functional relationship between fuzzy variables. In this paper, we firstly review the existing spectra extraction methods, then discuss the fuzzy methods about spectra extraction, so can provide new ideas, new methods and new theoretical foundations for the processing methods about two-dimensional fiber spectra extraction.

Marketing in a social network via structured groups outperforms spontaneous social conversations. It regulates the social interactions and thus the information pathways, which boosts overall impact. We start with a case study of a strongly-organized advertising network in Weibo, a popular microblogging service, which demonstrates that commercials promoted by this group are averagely twice effective as normal tweets. Then we present a modeling framework to characterize this structured diffusion paradigm. An analytical model using heterogeneous mean-field approximation was thus worked out to capture transmission dynamics. The transmission probability incorporates the inflation and propagation of node influences that explains why and how the structures within a campaign affect the spreading speed, scale, and impact. As empirical evidences, our model numerically simulates four typical structure settings on a large Twitter network. It confirms quantitatively that, hierarchical grouping excels the loosely or randomly coupled ones and classical marketing heuristics.

Integrating heterogeneous scientific dataset and providing universal collaborative services is an important goal for e-Science project of Chinese Academy of Sciences (CAS). In this paper, we present a universal cloud service for scientific dataset applications. We firstly design a resources pool container to support distributed heterogeneous scientific resources integration and continuous expansion. We then provide a scalable architecture to support application virtualization, which aims to support cloud service invocation applying back-end transparent resources pool. Finally an open interface is presented for third-party to develop customized applications. We give the experiments on the cloud service infrastructure of its performance, which shows our approach achieves considerable efficiency.

In microgblogs, a user usually follows or is followed by many other users. The content updating and reading is a complex process involving intensive interactions among publishers and readers. It also forms the basis of information diffusion in social networks. In the situation of massive followers, tweets reading would heavily depend on user behaviors and interactions. The tweets reading probability (TRP) would be a vital parameter measuring the effectiveness and influence of tweets. Our work proposed a fundamental model, namely competing-window, to simulate the process of multi-node interactions and analyzed TRP in social network. Based on Sina Microblog, we built a standard data set and run massive experiments on empirical data to extract user behavior patterns. By adopting simulating approaches, TRP in a none-preference social network was obtained. The results indicate that typical TRP is about 8% and different user behaviors affect TRP differently.

Microblog is a large-scale information sharing platform where intensive communications are taking place through interactive user behaviors. Previous studies have analyzed and modeled a series of traditional communications, such as letter, email and phone calls. The timing of human activities tends to be non-Poisson with bursts and heavy tails. Hence, several models have been proposed to explain human dynamics of bursts and heavy tails in various fields. However, as a newly developed product of Web2.0, microblog possesses inherent new characteristics, e.g. user-centric broadcast medium and asymmetric user relations. The communication in microblog is still poorly understood. Our work proposed an interest-driven model to simulate basic user communicating behaviors and processes. We came to the conclusion that, in microblogging communication, individual behaviors are bursts of rapidly occurring events separated by long periods of inactivity. Collective behaviors follow heavy-tailed Power Law distribution, whose origin is the descent of interests. Empirical statistics were also given to verify the model.

As a special signature, certificateless strong designated verifier scheme is a combination of certificateless cryptography with designated verifier scheme. Recently, Xiao et al gave a certificateless strong designated verifier scheme. In the paper, we analyze Xiao et al signature scheme and show that the scheme is insecure. Then We give the corresponding attack based on your analysis above and the reason to produce such attack. Finally, the improved scheme is given, electronic document is a "live" template. The various components of your paper [title, text, heads, etc.] are already defined on the style sheet, as illustrated by the portions given in this document.

Higher education tuition must take account of the quality of cultivation and the economic endurance of ordinary family. This requires a reasonable standard of higher education tuition to ensure the healthy and continual development of higher education. This paper focuses on four factors such as the social benefit from higher education, the cultivation quality of universities, the economic endurance of ordinary family, and the future income of students, using Analytic Hierarchy Process method to calculate the relative weights of factors to discover the importance of each factor in continual development of the higher education, farther set up a reasonable standard of higher education tuition.

The independent college(IC) has existed for more than ten years, and it has grown from baby to youth. Along with the extending of tertiary education, IC is faced with both opportunities and problems: more formal and stronger but more difficult to manage and instruct. In this paper, based on sixteen years of teaching experience which includes ten years in IC or something similar, we will introduce the changing attribute of IC and the endeavor we pay out to adapt the changing, such as self-built basis, design software to help students themselves understand the difficulty and abstract content under direction of teachers, then make students more confident, more curious and more fruitful.

Recently, Wang et. al presented a short group signature scheme without random oracles, and Kang et al. gave an efficient ID-based strong designated verifier signature scheme. And security proof of the two signature schemes were provided. Unfortunately, in this work we show that Wang et al.'s group signature is universally forgeable. Namely, any one can forge a group signature on arbitrary message, then an improved vision is presented; And we also show that Kang et al.'s scheme is forgeable, namely, a third party can produce a signature on arbitrary message m by a given signature information. Finally, we give the corresponding attack on the two signature schemes.

Digital signature schemes allow a signer to transform any arbitrary message into a signed message, such that anyone can verify the validity of the signed message by the signerpsilas public key. But, sometimes, we need to constrain the signerpsilas signature times. In this letter, we propose a k-times short signature scheme and show that the scheme is secure without random oracle. The scheme makes that the signer can only produce k times signature, and only need one time point multiplication operator in whole signing phase, and the size of the signature is only one element in a finite field. Thus the scheme is very suitable to mobile agent.

Ring signature is an anonymous signature which allows a user to anonymously sign on behalf of a group. In some cases, we only hope that our signatures were anonymously verified by the designated users, such as hospital records. In this works, by combining ring signature and designated verifier signature scheme, a ring signature scheme with Multi-designated verifiers are proposed to satisfy the multi-user setting. And by analyzing the security of scheme, we show that the proposed scheme is secure in a novel assumption: the Chosen-Target-Inverse-CDH problem under the random oracle model, and the corresponding security proof is given.

Because of the complication and abstract of computer hardware, it is a challenge to teach students such courses, especially the principles and organization of computers. This article aims at solving the problem through Blended Learning: introducing the basic conception and illustrating it at classroom, then practicing the typical content in virtual lab we designed, finally going to the lab to do physical experimentation. Besides these, we offer a tutor in web-site to provide questions & answers, the introduction of the content, the keystone of the content, and the difficulty of the content, along with the method to study it. It achieves better effect in practice.