Honggang Liu

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Most commonly used CAPTCHAs are text-based CAPTCHAs which relay on the distortion of texts in the background image. With the development of automated computer vision techniques, which have been designed to remove noise and segment the distorted strings to make characters readable for OCR, traditional text-based CAPTHCAs are not considered safe anymore for(More)
Graphical passwords are believed to be more secure than traditional textual passwords, but the authentications are usually complex and boring for users. Furthermore, most of the existing graphical password schemes are vulnerable to spyware and shoulder surfing. A novel graphical password scheme ColorLogin is proposed in this paper. ColorLogin is implemented(More)
CAPTCHAs are employed as a security measure to differentiate human users from bots. A new sound-based CAPTCHA is proposed in this paper, which exploits the gaps between human voice and synthetic voice rather than relays on the auditory perception of human. The user is required to read out a given sentence, which is selected randomly from a specified book.(More)
A novel self-adaptive image denoising model based on scale correlation and Stein’s unbiased risk estimate-linear expansion of thresholds (SURE-LET) in the nonsubsampled contourlet transform domain is proposed in this paper. First we implement the multidimensional and translation invariant decomposition for spatial images by the nonsubsampled contourlet(More)
IBM first proposed the conception of autonomic computing (AC) which provides a new way for computer technology. At present there are many researches on AC system, but less research on AC theory and evaluation. However it is the most import for the development of AC domain. In this paper, we mainly summarize present evaluation criteria, evaluation tools and(More)
  • Adarsh Baluni, Sayali Gole, +11 authors Rizwan Ur Rahman
  • 2013
Growth of Internet and its usage has made web services prone to malicious threats by automated scripts or bots. "Completely Automated Public Turing Test to tell Computers and Humans Apart", commonly abbreviated as CAPTCHA, is a technique used by web services to differentiate between humans and bots. [1] Most of these techniques are based on(More)
  • Roshni Rajavat, Bhavna Gala, +7 authors Ruyi Dai
  • 2015
Authentication is a process that ensures a user's identity. User's identity can be verified by user name and password. The textual passwords are the most widely used passwords for authentication. There is a common trend among users to choose short length passwords which are easy to memorize. However, textual passwords are vulnerable to various(More)
The world today is filled in with enormous amount of innovation and technology, Internet is thus stated to be one of the most beneficial part awarded to the society ,but web security is the crucial issue to be considered to ensure this a concept called CAPTCHA is developed. CAPTCHA stand for Completely Automated Public Turing test to tell Computer and Human(More)
Autonomic computing (AC) is a new domain, based on AC theory to design autonomic system is not perfect and implement process is more difficult. Especially, there lack tools and models to test the autonomic system. According to above-mentioned reason, this paper mainly discusses dependability of autonomic software. We proposed a model to analyze autonomic(More)
This paper focuses on a qualitative fault diagnosis method based on the integration and fusion of shallow and deep knowledge for liquid-propellant rocket engines (LRE). The paper firstly clarifies the concept and the types of LRE diagnosis knowledge. Later, from the isomorphic transform point of view, the paper analyses the correlation of different(More)