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    Design and Implementation of a Face Model in Video-realistic Speech Animation for Farsi Language

    , M.Sc. Thesis Sharif University of Technology Ghasemi Naraghi, Zeinab (Author) ; Jamzad, Mansour (Supervisor)
    With increasing use of computers in everyday life, improved communication between machines and human is needed. To make a right communication and understand a humankind face which is made in a graphical environment, implementing the audio and visual projects like lip reading, audio and visual speech recognition and lip modelling needed. The main goal in this project is natural representation of strings of lip movements for Farsi language. Lack of a complete audio and visual database for this application in Farsi language made us provide a new complete Farsi database for this project that is called SFAVD. It is a unique audio and visual database which covers the most applicable words, all... 

    A Secure DBMS Architecture to Preserve Data Privacy, Confidentiality, and Integrity

    , M.Sc. Thesis Sharif University of Technology Halvachi, Hadi (Author) ; Jalili, Rasool (Supervisor)
    While data outsourcing provides some benefits, it suffers from new privacy and security concerns, mainly about the confidentiality and integrity of the stored sensitive data, as well as enforcing access control policies. Current solutions to these aims are not comprehensive and consider only one aspect of security requirements. A secure DBMS architecture is introduced that simultaneously considers confidentiality, integrity and access control enforcement requirements. The transparency of security functions from data owner, service providers, and applications facilitates the operationality of the solution.Additionally, a new indexing technique for character encrypted data is proposed that... 

    A Secrecy-Preserving Access Control in Data Outsourcing Scenario

    , M.Sc. Thesis Sharif University of Technology Karimi, Leila (Author) ; Jalili, Rasool (Supervisor)
    One of the security issues in data outsourcing scenario is the enforcement of data owner’s access control policies. This includes three challenges; 1) the average number of keys needed to access authorized resources, 2) efficient update of policies, and 3) confidentiality of data owner’s access control policies. Most of the existing proposed solutions address only one of these challenges, while they impose high overhead on both the data owner and users. Such an overhead prevents the model to be implemented in practical applications. In this thesis, we propose an approach to address all the aforementioned challenges with acceptable overhead. In this approach, which is based on selective... 

    Using Functional Encryption to Manage Encrypted Data

    , M.Sc. Thesis Sharif University of Technology Mahfoozi, Rohollah (Author) ; Jalili, Rasool (Supervisor)
    Recently, many organizations outsource their data on an external server to rescue the trouble of data maintenance. But, data owners do not trust in the external server to enforce defined access control policies. In recent years, many researches was dedicated to cryptographic access control on outsourced data, in order to solve this problem. We introduce a method based on Attribute-based Encryption to enforce access control on outsourced data. In this method we consider policy updating and administrative access control. As a result The owner is not only able to change access control policies on outsourced data but also to define administrative rights (grant/revoke) for some admin users. Our... 

    Database Schema Extraction Prevention Through DBMS Error Handling

    , M.Sc. Thesis Sharif University of Technology Naghdi, Sepideh (Author) ; Amini, Morteza (Supervisor)
    Nowadays large volume of sensitive data of organizations are stored in the databases. Thus, databases are attractive to the attackers to execute different types of attacks with different purposes. The useful information that attackers try to achieve in the preliminary steps of the attacks against the databases, is the database structure or schema. One of the popular approach to extract the schema of a database is to analyze the returned error messages from its DBMS. Hence, a solution to prevent schema disclosure via the error messages is customizing and modifying them. To achieve this goal, in this thesis, we propose a framework to handle and customize the error messages automatically and... 

    Confidential Access to the Outsourced Relational Data

    , M.Sc. Thesis Sharif University of Technology NajmAbadi, Elahe Sadat (Author) ; Jalili, Rasool (Supervisor)
    In recent years, there has been a trend toward outsourcing data to the cloud provider. These companies must tackle the data security challenges. Generally these parties are assumed to be honest but curious. In past years, the research communities have been investigating different solution to ensure confidentiality.
    In addition to data confidentiality access and pattern confidentiality is a high-priority issue in some cases so. potential adversary should be unable to drive information from the observed access pattern to the outsourced data. Despite the fact that there are more investigation in the field of data confidentiality, concern over data security are the rise in outsourcing data,... 

    Query Optimization in Encrypted Database Systems

    , M.Sc. Thesis Sharif University of Technology Jafarinejad, Mahmoud (Author) ; Amini, Morteza (Supervisor)
    Protecting sensitive data stored in database systems, especially in outsourced ones, has become a major concern in many organizations. One of the main possible solutions is to encrypt data before storing them on databases. Bucket-based encryption is among different approaches proposed to accomplish this goal which besides its various benefits, suffers from generating false-positive results. Multi-join queries are one of the most important operations in database systems and their usage grows rapidly in comparison to other types of queries by increasing the size of stored information. While using the decision support systems and data mining solutions are growing continuously, executing... 

    An Access Control System for Time Series Data in NoSQL Databases

    , M.Sc. Thesis Sharif University of Technology Noury, Amir (Author) ; Amini, Morteza (Supervisor)
    An important class of applications which have been rapidly growing recently is the one that create and use time series data. These types of data sets are ordered based on the timestamps associated to their data items. In practice, traditional relational databases are unable to satisfy the requirements of these data sets; however, NoSQL databases with column-wide data structure are appropriate infrastructure for them. These databases are very efficient in read and write operations (especially for time series data, which are ordered) and are able to store unstructured data. Time series data may contain valuable and sensitive information; hence, they should be protected from the information... 

    Switching kalman filter based methods for apnea bradycardia detection from ECG signals

    , Article Physiological Measurement ; Volume 36, Issue 9 , 2015 , Pages 1763-1783 ; 09673334 (ISSN) Ghahjaverestan, N. M ; Shamsollahi, M. B ; Ge, D ; Hernandez, A. I ; Sharif University of Technology
    Apnea bradycardia (AB) is an outcome of apnea occurrence in preterm infants and is an observable phenomenon in cardiovascular signals. Early detection of apnea in infants under monitoring is a critical challenge for the early intervention of nurses. In this paper, we introduce two switching Kalman filter (SKF) based methods for AB detection using electrocardiogram (ECG) signal. The first SKF model uses McSharry's ECG dynamical model integrated in two Kalman filter (KF) models trained for normal and AB intervals. Whereas the second SKF model is established by using only the RR sequence extracted from ECG and two AR models to be fitted in normal and AB intervals. In both SKF approaches, a... 

    Security and searchability in secret sharing-based data outsourcing

    , Article International Journal of Information Security ; Volume 14, Issue 6 , November , 2015 , Pages 513-529 ; 16155262 (ISSN) Hadavi, M. A ; Jalili, R ; Damiani, E ; Cimato, S ; Sharif University of Technology
    Springer Verlag  2015
    A major challenge organizations face when hosting or moving their data to the Cloud is how to support complex queries over outsourced data while preserving their confidentiality. In principle, encryption-based systems can support querying encrypted data, but their high complexity has severely limited their practical use. In this paper, we propose an efficient yet secure secret sharing-based approach for outsourcing relational data to honest-but-curious data servers. The problem with using secret sharing in a data outsourcing scenario is how to efficiently search within randomly generated shares. We present multiple partitioning methods that enable clients to efficiently search among shared... 

    Speech driven lips animation for the Farsi language

    , Article Proceedings of the International Symposium on Artificial Intelligence and Signal Processing, AISP 2015, 3 March 2015 through 5 March 2015 ; 2015 , Pages 201-205 ; 9781479988174 (ISBN) Naraghi, Z ; Jamzad, M ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2015
    With the growing presence of computers in everyday life, communication improvement between human and machines is inevitable. Talking faces are the faces whose movements are synchronized to speech. They have an effective role in many applications. Lip is the most important part of a talking face. The main goal of this project is implementing a natural and human-like lip movement synthesis system for the Farsi language. For this purpose, a comprehensive audio visual database called SFAVD1 was designed and used. After extracting the sufficient features and designing a parallel Hidden Markov Model, the speech driven lip movement sequence generator system for Farsi input speech was implemented.... 

    A model-driven approach to semi-structured database design

    , Article Frontiers of Computer Science ; Volume 9, Issue 2 , 2015 , Pages 237-252 ; 20952228 (ISSN) Jahangard Rafsanjani, A ; Mirian Hosseinabadi, S ; Sharif University of Technology
    Higher Education Press  2015
    Recently XML has become a standard for data representation and the preferred method of encoding structured data for exchange over the Internet. Moreover it is frequently used as a logical format to store structured and semi-structured data in databases. We propose a model-driven and configurable approach for modeling hierarchical XML data using object role modeling (ORM) as a flat conceptual model. First a non-hierarchical conceptual schema of the problem domain is built using ORM and then different hierarchical views of the conceptual schema or parts of it are specified by the designer using transformation rules. A hierarchical modeling notation called H-ORM is proposed to show these... 

    Thirty-nine years of Iran's scientific products in the field of Geophysics

    , Article Journal of the Earth and Space Physics ; Volume 41, Issue 1 , 2015 , Pages 145-164 ; 03781046 (ISSN) Asadi, M ; Ghaderi Sohi, A ; Sharif University of Technology
    Institute of Geophysics  2015
    Identifying and measuring the impact and value of scientific output plays an important role in today's world of information overload. On one side, governments are trying to distribute research funds in ways that support research in strategically important fields, on the other side, researchers and scientists are seeking to access only relevant and quality information that have mainly worthy of their attention. Nowadays, countries are evaluated not only by their national products, military power, geographical area, etc., but also by such factors as the production and consumption of scientific information. Scientometric approaches are used to provide appropriate tools for evaluating scientific... 

    Knowledge-based design of space-time transmit code and receive filter for a multiple-input-multiple-output radar in signal-dependent interference

    , Article IET Radar, Sonar and Navigation ; Volume 9, Issue 8 , 2015 , Pages 1124-1135 ; 17518784 (ISSN) Karbasi, S. M ; Aubry, A ; Carotenuto, V ; Naghsh, M. M ; Bastani, M. H ; Sharif University of Technology
    Institution of Engineering and Technology  2015
    The authors deal with the robust design of multiple-input-multiple-output (MIMO) space-time transmit code (STTC) and space-time receive filter (STRF) for a point-like target embedded in signal-dependent interference. Specifically, they assume that the radar exploits knowledge provided by dynamic environmental database, to roughly predict the actual scattering scenario. Then, they devise an iterative method to optimise the (constrained) STTC and the (constrained) STRF which sequentially improves the worst-case (over interfering scatterers statistics) signal-to-interference-plus-noise ratio (SINR). Each iteration of the algorithm is handled via solving two (hidden) convex optimisation... 

    Parallel nonlinear analysis of weighted brain's gray and white matter images for Alzheimer's dementia diagnosis

    , Article Conference proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Conference ; 2010 , Pages 5573-5576 ; 1557170X (ISSN) Razavian, S. M ; Torabi, M ; Kim, K ; Sharif University of Technology
    In this study, we are proposing a novel nonlinear classification approach to discriminate between Alzheimer's Disease (AD) and a control group using T1-weighted and T2-weighted Magnetic Resonance Images (MRI's) of brain. Since T1-weighted images and T2-weighted images have inherent physical differences, obviously each of them has its own particular medical data and hence, we extracted some specific features from each. Then the variations of the relevant eigenvalues of the extracted features were tracked to pick up the most informative ones. The final features were assigned to two parallel systems to be nonlinearly categorized. Considering the fact that AD defects the white and gray regions... 

    Analyzing the supply chain using SCOR model in a steel producing company

    , Article 40th International Conference on Computers and Industrial Engineering, 25 July 2010 through 28 July 2010 ; 2010 ; 9781424472956 (ISBN) Seifbarghy, M ; Akbari, M. R ; Ssheikh Sajadieh, M ; Sharif University of Technology
    Supply Chain Operations Reference (SCOR) model is developed and maintained by the Supply Chain Council (SCC). The model is a reference model which can be used to map, benchmark and improve the supply chain operations. SCOR model provides companies with a basic process modeling tool, an extensive benchmark database and defines a set of supply chain metrics. Mobarakeh Steel Company (located in Isfahan, Iran) initiated the project of studying and analyzing its supply chain performance based on the SCOR model. This paper explains the steps and the results of the project. Interviews with the managers and considering the documents on the four major subjects of planning, logistics, information flow... 

    Towards an architecture for real-time data storage

    , Article Proceedings - 2nd International Conference on Computational Intelligence, Modelling and Simulation, CIMSim 2010, 28 September 2010 through 30 September 2010 ; 2010 , Pages 279-284 ; 9780769542621 (ISBN) Yektamanesh, O ; Habibi, J ; Ahmadi, H ; Vatanian Shanjani, G ; Sharif University of Technology
    Nowadays, due to the growing role that analytical, predictive and decision making activities perform in organizations, organizational data are very important. In order to utilizing organizational data, it should be transmitted from the operational and transactional environment to a dimensional or normal database. However, not only differences in platforms and data types are some issues that should be overcome, but also variety of data types such as non-structural and text format files should be considered. In this way, exploiting updated data storages is necessary for quick and accurate services and raising customers' satisfaction. Although real time data storages are frequently used in... 

    Heteroscedastic multilinear discriminant analysis for face recognition

    , Article Proceedings - International Conference on Pattern Recognition, 23 August 2010 through 26 August 2010, Istanbul ; 2010 , Pages 4287-4290 ; 10514651 (ISSN) ; 9780769541099 (ISBN) Safayani, M ; Manzuri Shalmani, M. T ; Sharif University of Technology
    There is a growing attention in subspace learning using tensor-based approaches in high dimensional spaces. In this paper we first indicate that these methods suffer from the Heteroscedastic problem and then propose a new approach called Heteroscedastic Multilinear Discriminant Analysis (HMDA). Our method can solve this problem by utilizing the pairwise chernoff distance between every pair of clusters with the same index in different classes. We also show that our method is a general form of Multilinear Discriminant Analysis (MDA) approach. Experimental results on CMU-PIE, AR and AT&T face databases demonstrate that the proposed method always perform better than MDA in term of classification... 

    User adaptive clustering for large image databases

    , Article Proceedings - International Conference on Pattern Recognition, 23 August 2010 through 26 August 2010, Istanbul ; 2010 , Pages 4271-4274 ; 10514651 (ISSN) ; 9780769541099 (ISBN) Saboorian, M. M ; Jamzad, M ; Rabiee, H. R ; Sharif University of Technology
    Searching large image databases is a time consuming process when done manually. Current CBIR methods mostly rely on training data in specific domains. When source and domain of images are unknown, unsupervised methods provide better solutions. In this work, we use a hierarchical clustering scheme to group images in an unknown and large image database. In addition, the user should provide the current class assignment of a small number of images as a feedback to the system. The proposed method uses this feedback to guess the number of required clusters, and optimizes the weight vector in an iterative manner. In each step, after modification of the weight vector, the images are reclustered. We... 

    A novel method to find appropriate ε for DBSCAN

    , Article Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), 24 March 2010 through 26 March 2010 ; Volume 5990 LNAI, Issue PART 1 , 2010 , Pages 93-102 ; 03029743 (ISSN) ; 3642121446 (ISBN) Esmaelnejad, J ; Habibi, J ; Hassas Yeganeh, S ; Sharif University of Technology
    Clustering is one of the most useful methods of data mining, in which a set of real or abstract objects are categorized into clusters. The DBSCAN clustering method, one of the most famous density based clustering methods, categorizes points in dense areas into same clusters. In DBSCAN a point is said to be dense if the ε-radius circular area around it contains at least MinPts points. To find such dense areas, region queries are fired. Two points are defined as density connected if the distance between them is less than ε and at least one of them is dense. Finally, density connected parts of the data set extracted as clusters. The significant issue of such a method is that its parameters (ε...