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Convolutional Neural Network Steganalysis's Application to Steganography [article]

Mehdi Sharifzadeh, Chirag Agarwal, Mohammed Aloraini, Dan Schonfeld
2017 arXiv   pre-print
This paper presents a novel approach to increase the performance bounds of image steganography under the criteria of minimizing distortion. The proposed approach utilizes a steganalysis convolutional neural network (CNN) framework to understand an image's model and embed in less detectable regions to preserve the model. In other word, the trained steganalysis CNN is used to calculate derivatives of the statistical model of an image with respect to embedding changes. The experimental results
more » ... that the proposed algorithm outperforms previous state-of-the-art methods in a wide range of low relative payloads when compared with HUGO, S-UNIWARD, and HILL by the state-of-the-art steganalysis.
arXiv:1711.02581v1 fatcat:d5c5u73rpna47oo3lybeowwkeu

AIDA [chapter]

Mehdi Sharifzadeh, Cyrus Shahabi, Bahareh Navai, Farid Parvini, Albert A. Rizzo
2004 Proceedings 2004 VLDB Conference  
In this demonstration, we show various querying capabilities of an application called AIDA. AIDA is developed to help the study of attention disorder in kids. In a different study [1] , we collected several immresive sensory data streams from kids monitored in an immersive application called the virtual classroom. This dataset, termed immersidata is used to analyze the behavior of kids in the virtual classroom environment. AIDA's database stores all the geometry of the objects in the virtual
more » ... ssroom environment and their spatio-temporal behavior. In addition, it stores all the immersidata collected from the kids experimenting with the application. AIDA's graphical user interface then supports various spatio-temporal queries on these datasets. Moreover, AIDA replays the immersidata streams as if they are collected in real-time and on which supports various continuous queries. This demonstration is a proof-of-concept prototype of a typical design and development of a domain-specific query and analysis application on the users' interaction data with immersive environments.
doi:10.1016/b978-012088469-8.50149-2 dblp:conf/vldb/SharifzadehSNPR04 fatcat:felgku3xozfkzgijydki4zb4gq

VoR-tree

Mehdi Sharifzadeh, Cyrus Shahabi
2010 Proceedings of the VLDB Endowment  
A very important class of spatial queries consists of nearestneighbor (NN) query and its variations. Many studies in the past decade utilize R-trees as their underlying index structures to address NN queries efficiently. The general approach is to use R-tree in two phases. First, R-tree's hierarchical structure is used to quickly arrive to the neighborhood of the result set. Second, the R-tree nodes intersecting with the local neighborhood (Search Region) of an initial answer are investigated
more » ... find all the members of the result set. While R-trees are very efficient for the first phase, they usually result in the unnecessary investigation of many nodes that none or only a small subset of their including points belongs to the actual result set. On the other hand, several recent studies showed that the Voronoi diagrams are extremely efficient in exploring an NN search region, while due to lack of an efficient access method, their arrival to this region is slow. In this paper, we propose a new index structure, termed VoR-Tree that incorporates Voronoi diagrams into R-tree, benefiting from the best of both worlds. The coarse granule rectangle nodes of R-tree enable us to get to the search region in logarithmic time while the fine granule polygons of Voronoi diagram allow us to efficiently tile or cover the region and find the result. Utilizing VoR-Tree, we propose efficient algorithms for various Nearest Neighbor queries, and show that our algorithms have better I/O complexity than their best competitors.
doi:10.14778/1920841.1920994 fatcat:764ke3luqfbpnemdw63yknzaze

The optimal sequenced route query

Mehdi Sharifzadeh, Mohammad Kolahdouzan, Cyrus Shahabi
2007 The VLDB journal  
Real-world road-planning applications often result in the formulation of new variations of the nearest neighbor (NN) problem requiring new solutions. In this paper, we study an unexplored form of NN queries named optimal sequenced route (OSR) query in both vector and metric spaces. OSR strives to find a route of minimum length starting from a given source location and passing through a number of typed locations in a particular order imposed on the types of the locations. We first transform the
more » ... SR problem into a shortest path problem on a large planar graph. We show that a classic shortest path algorithm such as Dijkstra's is impractical for most real-world scenarios. Therefore, we propose LORD, a light threshold-based iterative algorithm, which utilizes various thresholds to prune the locations that cannot belong to the optimal route. Then we propose R-LORD, an extension of LORD which uses R-tree to examine the threshold values more efficiently. Finally, for applications that cannot tolerate the Euclidean distance as estimation and require exact distance measures in metric spaces (e.g., road networks) we propose PNE that progressively issues NN queries on different point types to construct the optimal route for the OSR query. Our extensive experiments on both real-world and synthetic datasets verify that our algorithms significantly outperform a disk-based variation of the Dijkstra approach in terms of processing time (up to two orders of magnitude) and required workspace (up to 90% reduction on average). Keywords Spatial databases · Nearest neighbor search · Trip planning queries then we plan to dine in an Italian restaurant in early evening, and finally, we would like to watch a specific movie at late night. Naturally, we intend to drive the minimum overall distance to these destinations. That is, we need to find the locations of the shopping center s i , the Italian restaurant r j , and the theater t k that shows our movie, where traveling between these locations in the given order would result in the shortest travel distance (or time). Note that in this example, a time constraint enforces the order in which these destinations should be visited; we usually do not have dinner in the afternoon, or go for shopping at late night. This type of query is also essential in other application domains such as crisis management, air traffic flow management, supply chain management, and video surveillance. In crisis management, suppose that an ambulance needs to repeatedly visit one of the several attacked points a i and hospitals h j , respectively. The ambulance should visit as many of the attacked points as possible in the shortest time. The constraint that enforces the order in this example is that there is no reason for the ambulance to go to a hospital if it has not yet picked up an injured person. Note that in this example, although there are only two different types of points (i.e., attacked points and hospitals), the size of the sequence can become arbitrary large [e.g., (a 1 , h 1 , a 2 , h 2 , . . . , a i , h i ) ]. With the video surveillance application, consider searching for a sequence of relevant images of different scene types to discover an event. For instance, among time-stamped images showing individuals approaching a building, waiting in the lobby or leaving the building, we look for the minimal three images with approach/wait/leave sequence. Here, the distance could be defined according to high-dimensional feature space of images including their time-stamps. We call this type of queries where the order of points to be visited is given and fixed, the optimal sequenced route queries or OSR for short. Using Fig. 1 , we show that the OSR query cannot be optimally answered by simply performing a series of independent nearest neighbor searches from different locations. We use the first example described above as our running example throughout the paper. The figure shows a network of equally sized connected square cells, three different types of point sets shown by white, black and gray circles representing shopping centers, Italian restaurants, and theaters, respectively, and a starting point p (shown by ). A greedy approach to solve OSR is to first locate the closest shopping center to p, s 2 , then find the closest restaurant to s 2 , r 2 , and finally find the closest theater to r 2 , t 2 . Assuming the length of each edge of a cell is 1 unit, the total length of the route found by this greedy approach,
doi:10.1007/s00778-006-0038-6 fatcat:l4422sqtt5f5dof2noauybayga

The effect of arsenite on spatial learning: Involvement of autophagy and apoptosis

Behnoosh BonakdarYazdi, Fariba Khodagholi, Fatemeh Shaerzadeh, Azadeh Sharifzadeh, Ramesh Ahmadi, Mehdi Sanati, Hajar Mehdizadeh, Borna Payandehmehr, Leila Vali, Mehrnoush Moghaddasi Jahromi, Ghorban Taghizadeh, Mohammad Sharifzadeh
2017 European Journal of Pharmacology  
., Sharifzadeh, M., 2012. Nicotine attenuates spatial learning deficits induced by sodium metavanadate. Neurotoxicology 33, 44-52. Betin, V.M., Lane, J.D., 2009.  ...  ., 2012; Sharifzadeh et al., 2005) . Western blotting When probe test was done, rats were euthanized in a CO 2 chamber immediately and the hippocampus was bilaterally dissected.  ... 
doi:10.1016/j.ejphar.2016.12.023 pmid:27993642 fatcat:225ayegi6fdizgwgooez3eanzy

AB011. A review of dermatomyositis induced by drugs

Afsheen Sharifzadeh, Mehdi Rashighi
2019 Annals of Translational Medicine  
Keywords: Dermatomyositis (DM); drug-induced doi: 10.21037/atm.2019.AB011 Cite this abstract as: Sharifzadeh A, Rashighi M. A review of dermatomyositis induced by drugs.  ... 
doi:10.21037/atm.2019.ab011 fatcat:bm2ef2hydvgqhhmlb4nh3b3vne

A Comparison with two semantic sensor data storages in total data transmission [article]

Manaf Sharifzadeh, saeid aragy, Kaveh Bashash, Shahram Bashokian, mehdi gheisari
2014 arXiv   pre-print
The creation of small and cheap sensors promoted the emergence of large scale sensor networks. Sensor networks allow monitoring a variety of physical phenomena, like weather conditions (temperature, humidity, atmospheric pressure ...), traffic levels on highways or rooms occupancy in public buildings. Some of the sensors produce large volume of data such as weather temperature. These data should be stored somewhere for user queries. In this paper two known sensor data storage methods that store
more » ... data semantically has been compared and it has been shown that storing data in ontology form consumes more energy so the lifetime of sensor network would decreases. The reason we choose them is that they are useful and popular.
arXiv:1401.7499v1 fatcat:3jtvsjjsjrbu7hcm6msyfwpvya

Urinary melatonin levels and skin malignancy

Reza Ghaderi, Samineh Sehatbakhsh, Mehdi Bakhshaee, Gholam Reza Sharifzadeh
2014 Iranian Journal of Medical Sciences  
Melatonin inhibits tumor genesis in a variety of in vivo and in vitro experimental models of neoplasia. In industrialized societies, light at night, by suppressing melatonin production, poses a new risk for the development of a variety of cancers such as breast cancer. This effect on skin has been previously studied only in animals and not in humans. Our goal was to examine the relationship between 24-hour 6-sulphatoxymelatonin levels and skin cancer in a case-control study of 70 patients with
more » ... kin cancer and 70 healthy individuals. The level of 6-sulfatoxymelatonin was measured in 24-hour urine by the ELISA method. In the case group, 55 (78%) patients had basal cell carcinoma and 15 (22%) had squamous cell carcinoma. The mean level of 24-hour urine 6-sulfatoxymelatonin was significantly higher in the control group (P<0.001). Also, sleep duration had a significant difference between the two groups (P=0.001). It seems that a low level of 24-hour urinary 6-sulfatoxymelatonin renders human beings prone to skin cancer. This association, however, requires further investigation.
pmid:24453396 pmcid:PMC3895897 fatcat:vpobu5v3vff6bccnkd2nwznwyi

Change Detection in Time Series Data Using Wavelet Footprints [chapter]

Mehdi Sharifzadeh, Farnaz Azmoodeh, Cyrus Shahabi
2005 Lecture Notes in Computer Science  
In this paper, we propose a novel approach to address the problem of change detection in time series data. Our approach is based on wavelet footprints proposed originally by the signal processing community for signal compression. We, however, exploit the properties of footprints to capture discontinuities in a signal. We show that transforming data using footprints generates nonzero coefficients only at the change points. Exploiting this property, we propose a change detection query processing
more » ... cheme which employs footprint-transformed data to identify change points, their amplitudes, and degrees of change efficiently and accurately. Our analytical and empirical results show that our approach outperforms the best known change detection approach in terms of both performance and accuracy. Furthermore, unlike the state of the art approaches, our query response time is independent of the number of change points and the user-defined change threshold.
doi:10.1007/11535331_8 fatcat:ufgtm5trbfb6hkqfnsys4jhjna

Strong equality of Roman and perfect Roman domination in trees

Zehui Shao, Saeed Kosari, Hadi Rahbani, Mehdi Sharifzadeh, Seyed Mahmoud Sheikholeslami
2022 Reserche operationelle  
A Roman dominating function (RD-function) on a graph $G = (V, E)$ is a function $f: V \longrightarrow \{0, 1, 2\}$ satisfying the condition that every vertex $u$ for which $f(u) = 0$ is adjacent to at least one vertex $v$ for which $f(v) = 2$. An Roman dominating function $f$ in a graph $G$ is perfect Roman dominating function (PRD-function) if every vertex $u$ with $f(u) = 0$ is adjacent to exactly one vertex $v$ for which $f(v) = 2$. The (perfect) Roman domination number $\gamma_R(G)$
more » ... _{R}^{p}(G)$) is the minimum weight of an (perfect) Roman dominating function on $G$. We say that $\gamma_{R}^{p}(G)$ strongly equals $\gamma_R(G)$, denoted by $\gamma_{R}^{p}(G)\equiv \gamma_R(G)$, if every RD-function on $G$ of minimum weight is a PRD-function. In this paper we show that for a given graph $G$, it is NP-hard to decide whether $\gamma_{R}^{p}(G)= \gamma_R(G)$ and also we provide a constructive characterization of trees $T$ with $\gamma_{R}^{p}(T)\equiv \gamma_R(T)$.
doi:10.1051/ro/2022005 fatcat:yskridxuevd45a3tdxhvapa5jq

A New Parallel Message-distribution Technique for Cost-based Steganography [article]

Mehdi Sharifzadeh, Chirag Agarwal, Mahdi Salarian, Dan Schonfeld
2019 arXiv   pre-print
This paper presents two novel approaches to increase performance bounds of image steganography under the criteria of minimizing distortion. First, in order to efficiently use the images' capacities, we propose using parallel images in the embedding stage. The result is then used to prove sub-optimality of the message distribution technique used by all cost based algorithms including HUGO, S-UNIWARD, and HILL. Second, a new distribution approach is presented to further improve the security of
more » ... se algorithms. Experiments show that this distribution method avoids embedding in smooth regions and thus achieves a better performance, measured by state-of-the-art steganalysis, when compared with the current used distribution.
arXiv:1705.08616v2 fatcat:3vzcnxy6vfebzi3l53sqq4b6om

Utilizing Voronoi Cells of Location Data Streams for Accurate Computation of Aggregate Functions in Sensor Networks

Mehdi Sharifzadeh, Cyrus Shahabi
2007 Geoinformatica  
We prove in Sharifzadeh and Shahabi [11] that the Voronoi cell computed by the AVC-SW algorithm is a (1+")approximation to the actual Voronoi cell.  ...  A preliminary version of this work is presented in Sharifzadeh and Shahabi [12] , where Voronoi aggregation operator use the exact Voronoi cell at each node.  ... 
doi:10.1007/s10707-007-0024-1 fatcat:unjmk7rklbeebe6ktrbzix6bo4

A hybrid aggregation and compression technique for road network databases

Ali Khoshgozaran, Ali Khodaei, Mehdi Sharifzadeh, Cyrus Shahabi
2008 Knowledge and Information Systems  
Vector data and in particular road networks are being queried, hosted and processed in many application domains such as in mobile computing. Many client systems such as PDAs would prefer to receive the query results in unrasterized format without introducing an overhead on overall system performance and result size. While several general vector data compression schemes have been studied by different communities, we propose a novel approach in vector data compression which is easily integrated
more » ... thin a geospatial query processing system. It uses line aggregation to reduce the number of relevant tuples and Huffman compression to achieve a multi-resolution compressed representation of a road network database. Our experiments performed on an end-to-end prototype verify that our approach exhibits fast query processing on both client and server sides as well as high compression ratio.
doi:10.1007/s10115-008-0132-8 fatcat:s4fmbrfszrdabchmrjo7pja77u

Utilizing Voronoi Cells of Location Data Streams for Accurate Computation of Aggregate Functions in Sensor Networks

Mehdi Sharifzadeh, Cyrus Shahabi
2006 Geoinformatica  
We prove in Sharifzadeh and Shahabi [11] that the Voronoi cell computed by the AVC-SW algorithm is a (1+")approximation to the actual Voronoi cell.  ...  A preliminary version of this work is presented in Sharifzadeh and Shahabi [12] , where Voronoi aggregation operator use the exact Voronoi cell at each node.  ... 
doi:10.1007/s10707-005-4884-y fatcat:l2yihv7bpfgllkiutc4x2tn3pm

Supporting spatial aggregation in sensor network databases

Mehdi Sharifzadeh, Cyrus Shahabi
2004 Proceedings of the 12th annual ACM international workshop on Geographic information systems - GIS '04  
Sensor networks are unattended deeply distributed systems whose schema can be conceptualized using the relational model. Aggregation queries on the data sampled at each sensor node are the main means to extract the abstract characteristics of the surrounding environment. However, the non-uniform distribution of the sensor nodes in the environment leads to inaccurate results generated by the aggregation queries. In this paper, we introduce "spatial aggregations" that take into consideration the
more » ... istribution of the values generated by the sensor nodes. We propose the use of spatial interpolation methods derived from the fields of spatial statistics and computational geometry to answer spatial aggregations. In particular, we study Spatial Moving Average (SMA), Voronoi Diagram and Triangulated Irregular Network (TIN). Investigating these methods for answering spatial average queries, we show that the average value on the data samples weighted by the area of the Voronoi cell of the corresponding sensor node, provides the best precision. Consequently, we introduce an incremental algorithm to compute and maintain the Voronoi cell at each sensor node. To demonstrate the performance of in-network implementation of our algorithm, we have developed prototypes of two different approaches to distributed spatial aggregate processing.
doi:10.1145/1032222.1032248 dblp:conf/gis/SharifzadehS04 fatcat:j3exti4yknf5va4zv7kobd4p4q
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