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... 

Sending information secretly and communicating covertly have been of great interest for ages. For this purpose, text documents have been widely used and, consequently, various methods for hiding information in texts (text steganography) have been developed so far. This paper deals with a new method to hide information in Persian (Farsi) and Arabic texts. In the Unicode Standard, there are two different characters for "Ya" and "Kaf". The two characters of and have the same shape but different codes if they are used at the beginning or in the middle of words. As a result, we can hide information in texts, considering the specified data to be hidden and using one of these two characters (for... 

Steganography is a relatively new method for establishing hidden communication which gained attraction in recent years. Steganography is a method of hiding a secret message in a cover media such as image or text. In this paper a new method is proposed for steganography in English text by substituting the words which have different terms in British English and American English. © 2008 IEEE  

In this paper, two different systems for taking exams through the Internet are described and analyzed. They have been designed and executed in Yazd and Shahed Universities. These systems enable us to take the multiple-choice and descriptive exams. In these systems, the exam questions are prepared by the instructor of the concerned lesson and placed in the system database. The students who have taken that lesson can be connected to the system from wherever they want. After entering their username and password they can take part in the exam. One of these systems has been created on the basis of the synchronous model and another one has been developed on the basis of the asynchronous model.... 

Nowadays, many daily human activities such as education, commerce, talks, etc. are carried out through the Internet. In cases such as the registering in websites, some hackers write programs to make automatic false enrolments which waste the resources of the website while this may even stop the entire website from working. Therefore, it is necessary to tell apart human users from computer programs which is 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 are undesirable to human users. So the Non-OCR-Based CAPTCHA methods are... 

Invention of the Internet and its spread in the world changes various aspects of human life. In addition, Internet changed human relations. Chat is one of the new aspects which invented after the Internet and is welcomed by users, especially by young people. In chat rooms, people talk with each other using text messages. Because of the need for quick typing of the word and also because of the high amount of sentences which is exchanged between users, new abbreviations are invented for various words and phrases in chat rooms. This new language is known as SMS-Texting. On the other hand, the issue of safety and security of information and especially secret relationships has led to the... 

Today sending spams has turned to be a major problem in the Internet. In last 20 years, the Internet and mobile communication growth in parallel. So the spams are also born on the mobile phones as the form of SMS (Short Message Service) spams. In this paper a new method is proposed for filtering SMS spams using CAPTCHA (Completely Automatic Public Turing Test to Tell Computer and Human Apart) systems. CAPTCHA systems are used to distinguish between human users and computer programs automatically. In this method, the picture of an object is sent as an SMS picture message. Also name of that object and name of three other objects are written in the SMS as a multiple-choose question. The user... 

ITS (Intelligent Transportation System) can be applied to many fields. In this paper we present an ITS system for respiratory patients based on finding cleaner paths. In this system the information related to air pollution of different sections of the city is received from center of air-pollution information presentation and a path with least degree of air pollution is suggested. Therefore respiratory and cardiac patients can commute with fewer difficulties. In our project this system has been simulated manually. ©ICROS  

Currently, many daily human activities such as education, commerce and talks are carried out through the Internet. In cases such as the registering in websites, some hackers write programs to make automatic false enrolments which waste the resources of the website while this may even stop the entire website from working. Therefore, it is necessary to tell apart human users from computer programs which is 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 are undesirable to human users. In this paper a method has been presented for... 

Now we are able to offer numerous softwares for mobile phones after the advances in mobile phone industry. Most of these softwares should be bought in order that we can use them. Some of these softwares are sharewares and after buying them you have to insert an activation code given by the manufacturing company based on your mobile IMEI code in order to activate the software. In this paper a new method is introduced for sending the mobile software activation code by SMS (Short Message Service). In this method the activation code is hidden in an SMS picture message by steganography method and sent to the user. The software extracting the activation code from the picture and compare it with... 

Sudoku puzzle is a logical game which has recently got very popular. Every day various mass media print these puzzles. As a result these puzzles are a suitable alternative for hidden data transfer. SMS (short message service) is one of the popular mobile-phone services. In this service people can write short messages and send it to each other through mobile phones. In this paper a method has been presented for Steganography (hiding data) in Sudoku puzzles and through SMS. In this method after hiding data in a Sudoku puzzle, the puzzle is sent in a way that it does not attract any attention. Steganography algorithm is based on order of place of numbers 1 through 9 in one of the specified row... 

Many websites on the Internet offer services to people. They usually ask the users to fill the registration forms for using their services. Unfortunately, some vandalistic persons write programs which make automatic fake registration. For solving this problem, CAPTCHA (Completely Automated Public Turing test to tell Computers and Human Apart) systems are invented. These systems distinguish human users from computer programs. One of the CAPTCHA methods which is designed for Persian and Arabic users is Nastaliq CAPTCHA. In this method, the image of a Persian or Arabic word which is written in Nastaliq font is chosen from a dictionary, and it is shown to the users, then they are asked to type... 

Nowadays m-banking (mobile banking) is widely used in many banks. It has embarked upon supply of various services based on different systems and with the aid of various services such as the Short Message Service (SMS). However in developing countries such as Iran, m-banking is facing some challenges. One of these challenges is the issue of language of this system, because the main language of this system, in both side of bank system and customer mobile phone, is English. Also one of the main issues in m-banking services is the security of the systems. For solvin g the above problems, we proposed a method in this paper. By this method we send secure banking messages as well as Persian SMS for... 

Conveying information secretly and establishing hidden relationship has been of interest since long past. Text documents have been widely used since very long time ago. Therefore, we have witnessed different method of hiding information in texts (text steganography) since past to the present. In this paper we introduce a new approach for steganography in Persian and Arabic texts. Considering the existence of too many points in Persian and Arabic phrases, in this approach, by vertical displacement of the points, we hide information in the texts. This approach can be categorized under feature coding methods. This method can be used for Persian/Arabic Watermarking. Our method has been... 

Nowadays, many daily human activities such as education, trade, talks, etc are done by using the Internet. In such things as registration on Internet web sites, hackers write programs to make automatic false registration that waste the resources of the web sites while it may also stop it from functioning. Therefore, human users should be distinguished from computer programs. To this end, this paper presents a method for distinction of Persian and Arabic-language users from computer programs based on Persian and Arabic texts. Our proposed algorithm is based on adding a background to the image of a meaningless Persian/Arabic randomly generated word. This method relies on the difficulty of... 

Reusing the programs which have already been developed can shorten the production time and reduce costs and expenses. One of the important issues in software reuse is finding a program or a program component in a program library which has been already developed and using it in the new program. In view of precision and automation that formal methods can provide, we can use formal methods in retrieval appropriate components from the software libraries. In this paper, some of the works done in the field of retrieval of the components from the libraries by the help of formal methods have been surveyed and reviewed  

There are many websites specially designed for mobile phones. Some hackers write automated programs to abuse these website services and waste the website resources. Therefore, it is necessary to distinguish between human users and computer programs. Methods known for achieving this are known as CAPTCHA (Completely Automated Public Turing test to tell Computers and Human Apart). CAPTCHA methods are mainly based on the weaknesses of OCR (Optical Character Recognition) systems and ask the user to type a word. So using them is difficult in tools such as PDAs (Personal Digital Assistant) or mobile phones that lack a complete keyboard. In this paper, a new CAPTCHA system is proposed for... 

Nowadays, a great amount of information is circulated through the Internet. Some of them exclusively belong to a special group of users and require protection and safeguarding against unauthorized access. To this end, a category of systems called HIP (Human Interactive Proof) are designed to distinguish between various groups of users. An important task on the Internet websites is registration. Some hackers write programs to make fake registration that waste the resources of the web sites or even stop them from providing services. Therefore, human users should be distinguished from computer programs. CAPTCHA (Completely Automatic Public Turing Test to Tell Computer and Human Apart) methods... 

In some websites it is necessary to distinguishing between human users and computer programs which is 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 systems and using them are undesirable to human users. In this paper a method has been presented for distinguishing between human users and computer programs on the basis of choice of an object shown on the screen. In this method some objects are chosen randomly and the pictures of these topics are downloaded from the Internet. Then after applying some effects such as rotation, all of the pictures are shown on the screen. Then we ask the...