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    A Confidentiality and Integrity Preserving Architecture for Secure Data Outsourcing

    , M.Sc. Thesis Sharif University of Technology Shahrokhi, Hesamoddin (Author) ; Jalili, Rasool (Supervisor)
    Infrastructural costs of data management, have led people and organizations to outsource their data. This approach is facing with some significant security challenges and risks. The goal of this research, is to present an architecture for secure outsourcing of data in a way that used methods, storage processes, query processing methods and access control mechanisms work together to preserve confidentiality and integrity of outsourced data. In this architecture, the main challenge is transparent placement of some components between client and server in order to prevent user from being aware of communication with a secured server. In order to create this degree of transparency, we need to pay... 

    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... 

    Processing Queries with Mathematical Expressions on Encrypted Outsourced Databases

    , M.Sc. Thesis Sharif University of Technology Naseri Boroujeni, Saeed (Author) ; Jalil, Rasool (Supervisor)
    The ever-increasing volume of data and the lack of computational and storage facilities have caused a managerial challenge to organizations. The existence of these challenges on the one hand and the increase of storage services on the other hand have compelled the organizations to delegate their storage and management of data to the server providers of cloud storage services. The outsourcing of data to servers obviates the need for purchasing exorbitant storage equipment and recruiting professional workforce in the organization. Since the organization’s data will be kept outside the organization’s ambience in case of using such services in form of outsourcing, and the data will not be under... 

    Encryption Aware Query Processing for Data Outsourcing

    , Ph.D. Dissertation Sharif University of Technology Ghareh Chamani, Javad (Author) ; Jalili, Rasool (Supervisor)
    Data outsourcing provides cost-saving and availability guarantees. However, privacy and confidentiality issues, disappoint owners from outsourcing their data. Although solutions such as CryptDB and SDB tried to provide secure and practical systems, their enforced limitations, made them useless in practice. Inability in search on encrypted data, is one of the most important existing challenges in such systems. Furthermore, the overhead of mechanisms such as FHEs, removes them from considering for any practical system. Indeed, special purpose encryptions would be the only usable mechanisms for such purposes. However, their limited functionality does not support some important required... 

    Persian Compound Verb Database with the Verbal Element: “Shodan”

    , M.Sc. Thesis Sharif University of Technology Hashemnejad, Zeinab (Author) ; Khosravizadeh, Parvaneh (Supervisor) ; Shojaie, Razieh (Supervisor)
    Compound verbs (CVs) and its components, have been widely discussed in previous linguistics' researches as one of the most important and fundamental constructions of Persian language. Nevertheless most of the arguments and assumptions in those researches align with each other and studying CVs from another aspect with a different viewpoint has not been considered very much in order to solve nodes and issues in this area. We have endeavored in this thesis to review and criticize the portrayed definitions of the CVs, reconsider this construction and the syntactical and semantical roles of verbal and non-verbal elements in this combination from another point of view, and revise the previous... 

    , M.Sc. Thesis Sharif University of Technology Esnaashari, Zoha (Author) ; Kianfar, Fereydoon (Supervisor)
    Nowadays, NGOs have a special roll in solving social problems in the world. In regards to the developing state of these organizations in Iran, the need of adopting a systematic approach in managing these organizations, is bold. Renewing of the old methods of work in these organizations, is an aid to removing the barriers of development faced by these organizations.
    In this regard, this thesis subjects the reengineering of business processes of Rayehe Charity Foundation which is an NGO dealing with empowerment of households women.
    After studding the literature of reengineering, the thesis continues on introducing the organization and its activities in more detail. It categorizes... 

    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... 

    Geometrical Fracture Modeling Within Multiple-Point Statistics Framework

    , M.Sc. Thesis Sharif University of Technology Ahmadi, Rouhollah (Author) ; Masihi, Mohsen (Supervisor) ; Rasaei, Mohammad Reza (Supervisor) ; Eskandaridalvand, Kiomars (Supervisor) ; Shahalipour, Reza (Co-Advisor)
    Majority of the oil and gas reservoirs, in the main hydrocarbon production regions around the world, are naturally fractured reservoirs. Fractures play an important role in reservoir fluid flow either in the form of high permeable complex conduits or strong permeability anisotropies. Realistic characterization of naturally fractured reservoirs requires an exhaustive understanding of fracture connectivity and fracture pattern geometry. These subsequently demand description of many fracture parameters such as density (intensity), spacing, orientation, size and aperture. Therefore, a first step in fractured reservoirs characterization is the static geometric modeling of the subsurface fracture... 

    Modeling of Genetic Mutations Associated with Protein Pathway Common in Alzheimer, Parkinson and Macular Degeneration Diseases

    , M.Sc. Thesis Sharif University of Technology Ghahremani, Amin (Author) ; Jahed, Mehran (Supervisor) ; Hossein Khalaj, Babak (Supervisor) ; Shahpasand, Kourosh (Co-Supervisor)
    Extensive studies have been performed on the genetic variations involved in common neurodegenerative diseases such as Alzheimer's, macular degeneration, and Parkinson's. In most cases, no specific gene has been identified pointing to a distinct pathogenic pathway, therefore, this study mainly aims to find common genes among aforementioned diseases according to determination of a specific pathogenic protein pathway.In this study, we reached a deep understanding of the function of nervous system and the discovery of causative agents of the diseases by applying the sources of information from genome datasets in bioinformatics analysis. The utilized database comprises the classification of... 

    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,... 

    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... 

    Designing a Video Search System Using Topic Models

    , M.Sc. Thesis Sharif University of Technology Kianpisheh, Mohammad (Author) ; Gholampoor, Iman (Supervisor) ; Sharif Khani, Mohammad (Supervisor)
    In this work we present a surveillance video retrieval system based on Topic Models. We’ve shown that employing Dynamic Programming improve the effectiveness of Topic Model based retrival. In the other hand proposed method has the accuracy near to the low-level features based methods. Lightweight database is the major advantageous of propsed method over the low-level features based methods. In our work storage space occupied by database decreases from 42 MB to only 0.4 MB for the mit dataset. Moreover lightweight database strikingly speeded up the retrieval process, for example retrieval process in proposed method is about 24 times faster than low-level features based systems. Furthermore in... 

    A Trust-based Approach for Correctness Verification of Query Results in Data Outsourcing Scenario

    , M.Sc. Thesis Sharif University of Technology Ghasemi, Simin (Author) ; Jalili, Rasool (Supervisor)
    One of the security issues in database outsourcing scenario is the correctness of the query results. Correctness verification includes integrity, completeness and freshness of the results. Most of the proposed approaches for correctness verification impose high overhead on the components of the scenario which prevents the scenario to implemented in practical applications. In this thesis, we have proposed a probabilistic approach which imposes acceptable overhead for correctness verification of returned results of service provider. The approach uses the previous behavior of the service provider to calculate a trust value toward it which is used to adjust the imposed overhead. In other words,... 

    A Method for Searching on Encrypted Data

    , M.Sc. Thesis Sharif University of Technology Mansoori, Fatemeh (Author) ; Jalili, Rasool (Supervisor)
    Using database encryption to protect data in some situations where access control is not soleley enough is inevitable. Database encryption provides an additional layer of protecton to conventional access control techniques. It prevents unauthorized users, including intruders breaking into a network, from viewing the sensitive data. As a result data remains protected even in the event that database is successfully attacked or stolen. However, encryption and decryption of data result in database performance degradation. In the situation where all the information is stored in encrypted form, one cannot make the selection on the database content any more. Data should be decrypted first, so an... 

    A Secure and Effcient Approach for Processing Join Query on Encrypted Outsourced Data

    , M.Sc. Thesis Sharif University of Technology Hadian, Saman (Author) ; Jalili, Rasool (Supervisor)
    Data outsourcing As a cloud service, it is a solution to reduce the cost of data storage and management in small and medium organizations. One of the main concerns in this area is the privacy of data owners and the non-disclosure of information by curious (albeit trusted) public cloud service providers. Resolving this issue requires encrypting the data before sending it to the cloud server. Transferring all encrypted data to the cloud server and performing various queries after encryption imposes a lot of time, computational and storage overhead, which destroys the philosophy of outsourcing. One of the open research issues is the processing of join queries over encrypted data by the cloud... 

    An Approach for Secure Data Outsourcing

    , Ph.D. Dissertation Sharif University of Technology Hadavi, Mohammad Ali (Author) ; alili, Rasool (Supervisor)
    Data outsourcing is an approach to delegate the burden of data management to external servers. In spite of its clear advantages, data outsourcing requires security assurances including data confidentiality, query result correctness, and access control enforcement. Research proposals have identified solutions with disparate assumptions for different security requirements. It is a real obstacle towards having an integrated solution through the combination of existing approaches. The practicality of data outsourcing to the cloud is seriously affected by this challenge. In this thesis, a unified view based on secret sharing is proposed to simultaneously achieve confidentiality, correctness, and... 

    Cooperative Search and Localization of Mobile RF Ground Targets, Using a Group of UAVs

    , M.Sc. Thesis Sharif University of Technology Effati, Meysam (Author) ; Nobahari, Hadi (Supervisor)
    In this project, a method for cooperative search and localization of RF ground moving targets by a group of UAVs is developed. It should be noted that UAVs are just equipped with GPS and directional sensors. Since there is fuel constraint for UAVs, they take fuel from a tanker whenever they require. Moreover, searching method enables the UAVs to see different parts of the desired area with almost uniform distribution. In addition, the proposed approach enables the UAVs to perform a local search with the aim of finding the targets having lost their signal during localization mode. Finally, based upon a fueling decision function the UAVs take turn, approach to the fuel tanker, and start... 

    Speaker Adaptation in HMM-Based Persian Speech Synthesis

    , M.Sc. Thesis Sharif University of Technology Bahmaninezhad, Fahimeh (Author) ; Sameti, Hossein (Supervisor)
    Text-to-speech synthesis, one of the key technologies in speech processing, is a technique for generating speech signal from arbitrarily given text with target speaker’s voice characteristics and various speaking styles and emotional expressions. Statistical parametric speech synthesishasrecently been shown to be very effective in generating acceptable synthesized speech. Therefore, in this study,the main focus is on one of the instances of these techniquescalled hidden Markov model-based speech synthesis. In text-to-speech systems, it is desirable to synthesize high quality speech using a small amount of speech data; this goal would be achieved by employing speaker adaptation framework and... 

    Ontological Study of Metabolic Networks to Develop an Identification Software for Metabolic Networks

    , M.Sc. Thesis Sharif University of Technology Mohammadi Peyhani, Homa (Author) ; Bozorgmehry Boozarjomehry, Ramin (Supervisor)
    Simulation of biological behaviors as the pre requirement for control and optimization, especially for recognition and treating diseases, requires studying involved reactions which may or may not be accessible. In the other side, finding the correct network structures and related mathematical expressions to simulate biological behaviors is a complicated problem due to multi aspect interactions among biological reactions, which imply an approach that integrate the knowledge coming from multiple discipline including biological concepts, mathematical modelling, bioinformatics and advanced programming. In this study we aim to analyze this problem using ontological inference to develop a...