Sharif Digital Repository

Restricting children access to materials unsuitable for them such as violence scenes is very important for parents. So there is a feature named Parental Control in devices such as televisions and computers to define the contents children can access. The parental control setting must be protected from children and is usually done by a password. In this paper, we propose a new method for distinguishing between adult users and child users based on human speech. In our proposed method, the user must say a word and the adult users are identified by processing the speech. Our current implementation has 92.5% accuracy for distinguishing adult users from children. © 2008 IEEE  

Digital music technologies enable users to create and use large collections of music. One of the desirable features for users is the ability to automatically organize the collection and search in it. One of the operations that they need is automatic identification of tracks' artists. This operation can be used to automatically classify new added tracks to a collection. Additionally, the user can use this operation to identify the artist of an unknown track. The artist name of a track can help the user find similar music. In this paper, we introduce a fast and scalable system that can automatically identify the artist of music tracks. This system is creating a signature for each track that is... 

Multimedia files including audio, music and movies are important part of resources available on the Internet. With the expansion of personal computers and other digital devices such as digital cameras, ordinary people are also creating different multimedia files. Hence, there are huge amount of multimedia files in the Internet. Considering the volume of files available, we need automatic methods for indexing, classification and retrieval of multimedia files. But, there are a number of problems in processing multimedia files. Two important issues are the large size of multimedia files and different lengths of different files. In this PhD project, we want to develop a solution for these two... 

Speech is one of the main communication methods used by humans. So designing speech based interfaces for computer applications can ease the use of them for different users, especially disabled and elderly people. In this project, we want to design and implement a system that can identify user's group from his/her speech. We are working on two main applications: Parental Control and Completely Automated Public Turing test to tell Computers and Human Apart (CAPTCHA). In the Parental Control application, we want to distinguish between child users and adults based on human speech. This can be used to restrict child user access to adult materials such as adult websites. In the CAPTCHA... 

Upon development of m-commerce as one of the new branches of e-commerce, m-banking has emerged as one of the main divisions of m-commerce. As the m-banking was received very well, it has embarked upon supply of various services based on different systems and with the aid of various services such as the Short Messaging Service (SMS). However, in spite of its advantages, m-banking is facing some challenges as well. One of these challenges is the issue of security of this system. This paper presents a method for increasing security of the information requested by users with the use of steganography method. In this method, instead of direct sending of the information, it is hidden in a picture... 

The hidden, real-time sending and display of information, esp. in public places, has since long received attention and faced many challenges. Therefore, different methods have been proposed so far for hiding information in different cover media. In this paper I propose a new method for the real-time hiding of information without need to any storage cover media. This method is based on the real-time hiding of information in output screens of the instrument (such as screens shown by the monitor). This method of steganography is very similar to the two discussions of image steganography and video steganography. The idea suggested in this paper was simulated on a PC computer by using the Pascal... 

One of the important issues in security fields is hidden exchange of information. There are different methods for this purpose such as cryptography and steganography. Steganography is a method of hiding data within a cover media so that other individuals fail to realize their existence. In this paper a new method for steganography in English texts is proposed. In this method the US and UK spellings of words substituted in order to hide data in an English text. For example "color" has different spelling in UK (colour) and US (color). Therefore the data can be hidden in the text by substituting these words  

After rapid growth of the Internet, establishing hidden communication is an important subject of security that has gained increasing importance. One of the methods for establishing hidden communication is steganography. On the other hand with the expanding the use of mobile phones mobile telecommunication companies starting to add additional features to their mobile phones such as MMS (Multimedia Messaging Service) in order to attract more customers. Considering above statements, steganography in MMS messages is a good solution for establishing hidden communication. In this paper a new method for steganography in MMS messages using both text and image steganography methods is presented. This... 

In recent years by growing computer applications, new technologies are also invented. Meanwhile new issues are faced such as security. One of the security areas is hidden exchange of information which contains methods such as cryptography and steganography. Steganography is the art of hiding data in a cover media such as image or sound. In this paper a new method for Steganography in Persian and Arabic texts is presented. In this method pseudo-space character is used for hiding the data. This character prevents the Persian and Arabic letters from joining but without adding a space between the two and keeps the words closer together. Its code is 200C in Unicode hex notation. This character... 

After the emergence of modern technologies in the field of information technologies (IT), virtual learning has attained a new form. The way of announcing exams' grades is an important topic in e-learning. For announcing exams' grades on the web, various methods have been proposed. In this paper, first some common methods for announcing students' grades are reviewed, then three new methods which are named "Virtual Grade", "Steganography Grades", and "Grade HIP" are introduced and the result of implementing these methods for announcing the grades of some courses at the some Iranian universities are provided. Also these methods and their results are analyzed. Finally these three new methods are... 

After the emergence of modern technologies in recent years, learning methods have attained a new form. Using game consoles as educational tools is a new idea which is gained attracted by some researchers. This paper proposes a new method for improving English lab classes using Sony PSP (PlayStation Portable) handheld game consoles especially for Iranian schools. © 2008 IEEE  

There are many sites specially designed for mobile phones. In cases such as the registering in websites, some hackers write programs to make automatic false enrolments which waste the resources of the website. Therefore, it is necessary to distinguish between human users and computer programs. These systems are known as CAPTCHA (Completely Automated Public Turing test to tell Computers and Human Apart). CAPTCHA methods are mainly based on the weak points of OCR (Optical Character Recognition) systems while using them difficult in tools such as PDAs (Personal Digital Assistant) or mobile phones that lack a big keyboard. So the Non-OCR-Based CAPTCHA methods are proposed which are do not need... 

Recently Mobile Learning (M-Learning) has attracted much attention. Due to advantages of SMS (Short Messaging Service) on mobile phones we present a safe and protected method for taking multiple-choice quizzes by using the SMS on mobile phones in this paper. In this method questions of quiz are sent to students along with their answers through some SMS messages. The students will receive their grades immediately after answering the questions and this grade is also sent to the instructor or professor along with the student's answers through an SMS Picture Message. Answers of questions and the student's grade are hidden in SMS picture message through stenography and then they are sent. The... 

By rapid growth of technology in recent years, many services are provided for disabled people. Using wireless devices such as mobile phones in healthcare is a new idea which is gained attracted by some developers in recent years. On the other hand, nowadays game consoles are not only for playing games, but also have more functions such as using for education. Considering the above mentioned facts, this paper proposes a method to aid speech-impaired children using Nintendo DS Game console. This method helps the speech-impaired children which are not capable of using sign language well to communicate with others until they learn sign language well. Because the Nintendo DS is the most popular... 

After expanding the use of computer and its affect on different aspect of life, the copyright issue has gained many attractions. For this purpose watermarking methods are proposed. In these methods a code is embedded into digital material that can be used to approve ownership, it can be visible or invisible to the user. On the other hand with the rapid growth of mobile phones, mobile telecommunication companies starting to add additional features to their mobile phones such as MMS (Multimedia Messaging Service) in order to attract more customers. MMS is a technology that allows mobile phones sending messages that includes multimedia objects esp. images. For copyright protection of images... 

By a great leap, the computer game industry has today reached fame as big as filmmaking industry. Upon introduction of the new generation of game consoles, this industry will witness spectacular progress. One of these next generation consoles is Nintendo console named "Wii". This console has a new game pad which utilizes motion sensors. On the other hand, facilities such as internet connection are added in new consoles and they are not merely for playing. It is observed that placing password for creating usernames by game consoles is difficult. By the use of the specifications of Wii console game pads, a method for user authentication and entering password is proposed in this paper. By using... 

Following the expansion of Internet, many software were produced that could launch through Internet without prior installation on computers. This included game software and software that deal with financial affairs. These softwares are mainly in Java language and can be found on web pages as Java Applets. Some software owners want that their products only able to execute through their own web pages so that no one could put them on other web pages. In this paper, a new method has been presented to protect Java Applets from copying by using "Steganography in HTML web pages" method. In this method, a special 8-character string is hidden in the HTML page by a secret key. The string and the... 

Delivering first aid before transferring patients to hospital is among keys to survival. Moreover, calling the emergency center as soon as possible and providing brief information about the patient are helpful for the emergency center to dispatch specialized medical team and equipments proportionate to the conditions of the patient. Mobile phone is a device which many people use and always carry with them. One more thing is that SMS (Short Message Service) stands as a favorite service in mobile network, used to exchange short messages and featuring low cost, non-stop lines of dispatch, possibilities for offline work and so forth. This paper puts forward procedures of calling an emergency... 

Mobile phone and Internet technologies have progressed along each other. The importance of both these technologies has resulted in the creation of a new technology for establishing wireless Internet connection through mobile phone, known as Wireless Application Protocol (WAP). However, considering the importance of the issue of data security and especially establishing hidden communications, many methods have been presented. In the meanwhile, steganography is a relatively new method. In this paper, a method for hidden exchange of data has been presented by using steganography on WML pages (WML stands for Wireless Markup Language, which is a language for creating web pages for the WAP). The... 

Tourism industry is an important and money-making profession in many countries. The appropriate and quick submission of primary information such as historical sites to the tourists is very effective in attracting them. Of course the tourism tools have undergone some changes and variations in accordance with technology advances and development of people's behavior in recent years. So tourism services should be developed and improved in parallel these changes in order to be successful in attraction of tourists. Considering the above mentioned facts, this paper proposes a system for providing city maps for tourists on their Nintendo DS Game console. Because the Nintendo DS is the most popular...