CAPTCHAs are known as Captcha which stands for Completely Automated Public Turing test to tell Computer and Human Apart. used prevent automated scripts from harvesting email addresses publicly accessible forms on the internet submitting them spammers. mostly utilised because computers have a difficult time deciphering text concealed behind distorted visuals, but humans an easier information hid...

In this paper, an automatic method for Persian WordNet construction based on Prenceton WordNet 2.1 (PWN) is introduced. The proposed approach uses Persian and English corpora as well as a bilingual dictionary in order to make a mapping between PWN synsets and Persian words. Our method calculates a score for each candidate synset of a given Persian word and for each of its translation, it select...

CAPTCHA is an acronym that stands for Completely Automated Public Turing Test to tell Computers and Humans Apart (CAPTCHA), it a good example of authentication system can be used determine the true identity any user. It serves as security measure prevent attack caused by web bots (automatic programs) during online transaction. come text-based or image-based depending on project programmer. The ...

-------------------------------------------------------------ABSTRACT-------------------------------------------------------A novel technique of Captcha is regenerated by using composite images that are generated in the given data base. Captcha is a type of challenge response test used in computing to determine whether or not the user is human. Captcha are used to prevent bots or automated prog...

Since their inception, captchas have been widely used for preventing fraudsters from performing illicit actions. Nevertheless, economic incentives have resulted in an arms race, where fraudsters develop automated solvers and, in turn, captcha services tweak their design to break the solvers. Recent work, however, presented a generic attack that can be applied to any text-based captcha scheme. F...

Persian is one of the Indo-European languages which has borrowed its script from Arabic, a member of Semitic language family. Since Persian and Arabic scripts are so similar, problems arise when we want to process an electronic text. In this paper, some of the common problems faced experimentally in developing a corpus for Persian are discussed. The sources of the problems are the Persian scrip...

The Persian language is one of the dominant languages in the Middle East, so there are significant amount of Persian documents available on the Web. Due to the special and different nature of the Persian language compared to other languages like English, the design of information retrieval systems in Persian requires special considerations. However, there are relatively few studies on retrieval...