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Estimating data hiding capacity of gray scale images based on its bitplanes structure
, Article 2008 4th International Conference on Intelligent Information Hiding and Multiedia Signal Processing, IIH-MSP 2008, Harbin, 15 August 2008 through 17 August 2008 ; 2008 , Pages 261-264 ; 9780769532783 (ISBN) ; Jamzad, M ; Sharif University of Technology
2008
Abstract
Determining the capacity of image for data hiding is a complex task. This capacity may be influenced by many factors such as the content of image and also Human Visual System (HVS). A few works on this topic are reported. In this paper we propose a new method for calculating capacity in gray scale images. Our method is based on measuring Smoothness and Connectivity of neighbors of a specific pixel in image bitplanes. This method can produce a signed integer for each pixel capacity such that the sign shows the modification in pixel value must be increasing or decreasing. Comparison with the existing methods showed that the proposed method gave better estimation for capacity of data hiding in...
Detection of regional copy/move forgery in MPEG videos using optical flow
, Article Proceedings of the International Symposium on Artificial Intelligence and Signal Processing, AISP 2015, 3 March 2015 through 5 March 2015 ; March , 2015 , Pages 13-17 ; 9781479988174 (ISBN) ; Ghaemmaghami, S ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2015
Abstract
With rapid proliferation of affordable video capturing devices and state-of-the-art video editing software tools, it is now easier than ever to manipulate video contents. In this paper a passive method for copy/move video forgery detection in MPEG videos is proposed. The method first divides each video frame into suspicious and apparently innocent parts. Subsequently, an optical flow coefficient is computed from each part. Forgeries are located when an unusual trend in the optical flow coefficient of the suspicious object is detected. Experiments on a set of forged and original sequences validate the justifications made by the proposed method
Java applets copy protection by steganography
, Article 2006 International Conference on Intelligent Information Hiding and Multimedia Signal Processing, IIH-MSP 2006, Pasadena, CA, 18 December 2006 through 20 December 2006 ; 2006 , Pages 388-391 ; 0769527450 (ISBN); 9780769527451 (ISBN) ; Sharif University of Technology
IEEE Computer Society
2006
Abstract
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...
Improving Live Virtual Machine Migration Technique in Cloud Computing Environment
, M.Sc. Thesis Sharif University of Technology ; Movaghar Rahimabadi, Ali (Supervisor)
Abstract
Virtualizing the cloud data center as multiple VMs running parallel on a cloud server is a practical solution to the exponentially grown number of cloud users. The fluctuations in the number of required resources, like networking, storage, and computing resources, can be met by dynamic VM migration. The method by which cloud providers manage VMs and hardware resources to decrease costs and ensure the quality of services is of great importance, especially when the cloud is under a heavy workload. VM migration is one of the most fundamental and practical practices in managing the clouds. Despite all the benefits of VM migration, it also brings overhead on the source host, destination host, and...
Linear-quadratic blind source separating structure for removing show-through in scanned documents
, Article International Journal on Document Analysis and Recognition ; Volume 14, Issue 4 , 2011 , Pages 319-333 ; 14332833 (ISSN) ; Babaie Zadeh, M ; Jutten, C ; Sharif University of Technology
2011
Abstract
Digital documents are usually degraded during the scanning process due to the contents of the backside of the scanned manuscript. This is often caused by the show-through effect, i. e. the backside image that interferes with the main front side picture due to the intrinsic transparency of the paper. This phenomenon is one of the degradations that one would like to remove especially in the field of Optical Character Recognition (OCR) or document digitalization which require denoised texts as inputs. In this paper, we first propose a novel and general nonlinear model for canceling the show-through phenomenon. A nonlinear blind source separation algorithm is used for this purpose based on a new...
A nonlinear blind source separation solution for removing the show-through effect in the scanned documents
, Article 16th European Signal Processing Conference, EUSIPCO 2008, Lausanne, 25 August 2008 through 29 August 2008 ; 2008 ; 22195491 (ISSN) ; Babaie Zadeh, M ; Jutten, C ; Sharif University of Technology
2008
Abstract
Digital documents are usually degraded during the scanning process due to the printings existing on the backside of the scanning manuscript. This is often caused by the so called show-through effect, the image that interferes with the main picture due to the intrinsic opacity of the paper. This phenomenon is on type of degradation that one would like to remove. In this paper, we propose a novel and general nonlinear model for show-through phenomenon. A nonlinear blind source separation (BSS) algorithm is used for this particular application in a new recursive and extendible structure for compensating show-through. Finally, we introduce a new structure for removing the show-through and the...
Unsupervised, fast and efficient colour-image copy protection
, Article IEE Proceedings: Communications ; Volume 152, Issue 5 , 2005 , Pages 605-616 ; 13502425 (ISSN) ; Kasaei, S ; Sharif University of Technology
2005
Abstract
The ubiquity of broadband digital communications and mass storage in modern society has stimulated the widespread acceptance of digital media. However, easy access to royalty-free digital media has also resulted in a reduced perception in society of the intellectual value of digital media and has promoted unauthorised duplication practices. To detect and discourage the unauthorised duplication of media, researchers have investigated watermarking methods to embed ownership data into media. However, some authorities have expressed doubt over the efficacy of watermarking methods to protect digital media. The paper introduces a novel method to discourage unauthorised duplication of digital...
Meta-aligner: long-read alignment based on genome statistics
, Article BMC Bioinformatics ; Volume 18, Issue 1 , 2017 ; 14712105 (ISSN) ; Aliyari, A ; Ahmadian Moghadam, A ; Edrisi, M. A ; Motahari, S. A ; Khalaj, B. H ; Sharif University of Technology
Abstract
Background: Current development of sequencing technologies is towards generating longer and noisier reads. Evidently, accurate alignment of these reads play an important role in any downstream analysis. Similarly, reducing the overall cost of sequencing is related to the time consumption of the aligner. The tradeoff between accuracy and speed is the main challenge in designing long read aligners. Results: We propose Meta-aligner which aligns long and very long reads to the reference genome very efficiently and accurately. Meta-aligner incorporates available short/long aligners as subcomponents and uses statistics from the reference genome to increase the performance. Meta-aligner estimates...
Exploration of Existing Patterns in Copy Number Variations of Genetic Diseases and Disorders
, Ph.D. Dissertation Sharif University of Technology ; Rabiee, Hamid Reza (Supervisor)
Abstract
One of the main sources of genetic variations are structural variations, including the widespread Copy Number Variations (CNVs). CNVs include two types, copy of genetic material (duplication) and loss of part of genetic sequence (deletion) and typically range from one kilobase pairs (Kbp) to several megabase pairs (Mbp) in size. Most of the copy number variations are occured in in healthy people; however, these variants can also contribute to numerous diseases through several genetic mechanisms (e.g. change gene dosage through insertions, duplications or deletions). The CNV study can provide greater insight into the etiology of disease phenotypes. Nowadays, with the huge amount of investment...
A simple geometrical approach for deinterleaving radar pulse trains
, Article Proceedings - 2016 UKSim-AMSS 18th International Conference on Computer Modelling and Simulation, UKSim 2016, 6 April 2016 through 8 April 2016 ; 2016 , Pages 172-177 ; 9781509008889 (ISBN) ; Pezeshk, A. M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2016
Abstract
Some periodic and quasi-periodic pulse trains are emitted by different sources in the environment and a number of sensors receive them through a single channel simultaneously. We are often interested in separating these pulse trains for source identification at sensors. This identification process is termed as deinterleaving pulse trains. Deinterleaving pulse trains has wide applications in communications, radar systems, neural systems, biomedical engineering, and so on. This paper studies the deinterleaving problem with the assumption that both sources and sensors are fixed. In this study, the problem of deinterleaving pulse trains is modeled as a blind source separation (BSS) problem. To...
Designing a new procedure for reward and penalty scheme in performance-based regulation of electricity distribution companies
, Article International Transactions on Electrical Energy Systems ; Volume 28, Issue 11 , 2018 ; 20507038 (ISSN) ; Abbaspour, A ; Fotuhi Firuzabad, M ; Moeini Aghtaie, M ; Lehtonen, M ; Sharif University of Technology
John Wiley and Sons Ltd
2018
Abstract
This paper introduces a new fuzzy-based design procedure for more efficient application of reward-penalty schemes in distribution sector. To achieve a fair as well as applicable regulation scheme, the fuzzy C-means clustering algorithm is employed to efficiently determine the similarity among distribution companies. As setting procedure of the reward-penalty scheme parameters can significantly affect the income of different companies, a new procedure based on the membership degrees obtained from the fuzzy C-means algorithm is proposed to fairly determine these parameters for each electricity distribution company. Some numerical studies are performed on the Iranian electricity distribution...
Application of Fuzzy C-means algorithm as a novel approach to predict solubility of hydrocarbons in carbon dioxide
, Article Petroleum Science and Technology ; Volume 36, Issue 4 , 2018 , Pages 308-312 ; 10916466 (ISSN) ; Garmsiri, H ; Zare, M ; Hemmati, N ; Sharif University of Technology
Taylor and Francis Inc
2018
Abstract
In the recent years, declination of oil reservoir causes the importance of researches on enhancement of oil recovery processes become more important. One of wide applicable approaches in enhancement of oil recovery is carbon dioxide injection which becomes interested because of relative low cost, good displacement and environmentally aspects. The injection of carbon dioxide to oil reservoir causes the lighter hydrocarbons of crude oil are extracted by CO2. This phenomena can be affected by various factors such the solubility of hydrocarbons in carbon dioxide so in the present investigation Fuzzy c-means (FCM) as a novel approach for estimation of solubility of alkanes in carbon dioxide in...
How does cobalt phosphate modify the structure of TiO2 nanotube array photoanodes for solar water splitting?
, Article Catalysis Today ; Volume 335 , 2019 , Pages 306-311 ; 09205861 (ISSN) ; Naseri, N ; Calloni, A ; Bussetti, G ; Sharif University of Technology
Elsevier B.V
2019
Abstract
TiO2 nanotube arrays (TNA) have been modified by cobalt phosphate (CoPi) through potentiostatic electrodeposition method. Different samples have been prepared by changing the loaded CoPi through the deposition time from 10 to 960 min. Formed catalytic materials have been characterized by different methods. Although charge transfer resistance of the CoPi/TNA photoanodes have been decreased from 5.5 to 4.0 kΩ by increasing the deposition time from 5 to 60 min, the maximum photoresponse was obtained for 10 min CoPi deposition leading to 24% more photocurrent compare to bare TNA which proposed optimum value for cobalt phosphate decoration. Based on field emission scanning electron microscopy...