Interactive image manipulation using morphological trees and spline-based skeletons

The ability to edit an image using intuitive commands and primitives is a desired feature for any image editing software. In this paper, we combine recent results in medial axes with the well-established morphological tree representations to develop an interactive image editing tool that provides global and local image manipulation using high-level primitives. We propose a new way to render interactive morphological trees using icicle plots and introduce different ways of manipulating spline-based medial axis transforms for grayscale and colored image editing. Different applications of the tool, such as watermark removal, image deformation, dataset augmentation for machine learning, artistic illumination manipulation, image rearrangement, and clothing design, are described and showcased on examples

Web Service Deployment for Selecting a Right Steganography Scheme for Optimizing Both the Capacity and the Detectable Distortion

The principal objective of this effort is to organize a network facility to hide the secret information in an image folder without disturbing its originality. In the literature lot of algorithms are there to hide the information in an image file but most of it consumes high resource for completing the task which is not suitable for light weight mobile devices. Few basic algorithms like 1LSB, 2LSB and 3LSB methods in the literature are suitable for mobile devices since the computational complexity is very low. But, these methods either lack in maintaining the originality of the source image or in increasing the number of bits to be fixed. Furthermore, every algorithm in the literature has its own merits and demerits and we cannot predict which algorithm is best or worst since, based on the parameters such as size of the safety duplicate and encryption algorithm used to generate the cipher text the steganography schemes may produce best or worst result with respect to computational complexity, capacity, and detectable distortion. In our proposed work, we have developed a web service that takes cover image and plain text as the input from the clients and returns the steganoimage to the clients. The steganoimage will be generated by our proposed work by analyzing the above said parameters and by applying the right steganography scheme. The proposed work helps in reducing the detectable distortion, computational complexity of the client device, and in increasing the capacity. The experimental result says that, the proposed system performs better than the legacy schemes with respect to capacity, computational complexity, and detectable distortion. This proposed work is more useful to the client devices with very low computational resource since all the computational tasks are deployed in the server side

WM-NET: Robust Deep 3D Watermarking with Limited Data

The goal of 3D mesh watermarking is to embed the message in 3D meshes that can withstand various attacks imperceptibly and reconstruct the message accurately from watermarked meshes. Traditional methods are less robust against attacks. Recent DNN-based methods either introduce excessive distortions or fail to embed the watermark without the help of texture information. However, embedding the watermark in textures is insecure because replacing the texture image can completely remove the watermark. In this paper, we propose a robust deep 3D mesh watermarking WM-NET, which leverages attention-based convolutions in watermarking tasks to embed binary messages in vertex distributions without texture assistance. Furthermore, our WM-NET exploits the property that simplified meshes inherit similar relations from the original ones, where the relation is the offset vector directed from one vertex to its neighbor. By doing so, our method can be trained on simplified meshes(limited data) but remains effective on large-sized meshes (size adaptable) and unseen categories of meshes (geometry adaptable). Extensive experiments demonstrate our method brings 50% fewer distortions and 10% higher bit accuracy compared to previous work. Our watermark WM-NET is robust against various mesh attacks, e.g. Gauss, rotation, translation, scaling, and cropping

Host-parasite coevolution promotes innovation through deformations in fitness landscapes

During the struggle for survival, populations occasionally evolve new functions that give them access to untapped ecological opportunities. Theory suggests that coevolution between species can promote the evolution of such innovations by deforming fitness landscapes in ways that open new adaptive pathways. We directly tested this idea by using high- throughput gene editing- phenotyping technology (MAGE- Seq) to measure the fitness landscape of a virus, bacteriophage λ, as it coevolved with its host, the bacterium Escherichia coli. An analysis of the empirical fitness landscape revealed mutation- by- mutation- by- host- genotype interactions that demonstrate coevolution modified the contours of λ’s landscape. Computer simulations of λ’s evolution on a static versus shifting fitness landscape showed that the changes in contours increased λ’s chances of evolving the ability to use a new host receptor. By coupling sequencing and pairwise competition experiments, we demonstrated that the first mutation λ evolved en route to the innovation would only evolve in the presence of the ancestral host, whereas later steps in λ’s evolution required the shift to a resistant host. When time- shift replays of the coevo-lution experiment were run where host evolution was artificially accelerated, λ did not innovate to use the new receptor. This study provides direct evidence for the role of coevolution in driving evolutionary novelty and provides a quantitative framework for predicting evolution in coevolving ecological communities

Data Hiding in Digital Video

With the rapid development of digital multimedia technologies, an old method which is called steganography has been sought to be a solution for data hiding applications such as digital watermarking and covert communication. Steganography is the art of secret communication using a cover signal, e.g., video, audio, image etc., whereas the counter-technique, detecting the existence of such as a channel through a statistically trained classifier, is called steganalysis. The state-of-the art data hiding algorithms utilize features; such as Discrete Cosine Transform (DCT) coefficients, pixel values, motion vectors etc., of the cover signal to convey the message to the receiver side. The goal of embedding algorithm is to maximize the number of bits sent to the decoder side (embedding capacity) with maximum robustness against attacks while keeping the perceptual and statistical distortions (security) low. Data Hiding schemes are characterized by these three conflicting requirements: security against steganalysis, robustness against channel associated and/or intentional distortions, and the capacity in terms of the embedded payload. Depending upon the application it is the designer\u27s task to find an optimum solution amongst them. The goal of this thesis is to develop a novel data hiding scheme to establish a covert channel satisfying statistical and perceptual invisibility with moderate rate capacity and robustness to combat steganalysis based detection. The idea behind the proposed method is the alteration of Video Object (VO) trajectory coordinates to convey the message to the receiver side by perturbing the centroid coordinates of the VO. Firstly, the VO is selected by the user and tracked through the frames by using a simple region based search strategy and morphological operations. After the trajectory coordinates are obtained, the perturbation of the coordinates implemented through the usage of a non-linear embedding function, such as a polar quantizer where both the magnitude and phase of the motion is used. However, the perturbations made to the motion magnitude and phase were kept small to preserve the semantic meaning of the object motion trajectory. The proposed method is well suited to the video sequences in which VOs have smooth motion trajectories. Examples of these types could be found in sports videos in which the ball is the focus of attention and exhibits various motion types, e.g., rolling on the ground, flying in the air, being possessed by a player, etc. Different sports video sequences have been tested by using the proposed method. Through the experimental results, it is shown that the proposed method achieved the goal of both statistical and perceptual invisibility with moderate rate embedding capacity under AWGN channel with varying noise variances. This achievement is important as the first step for both active and passive steganalysis is the detection of the existence of covert channel. This work has multiple contributions in the field of data hiding. Firstly, it is the first example of a data hiding method in which the trajectory of a VO is used. Secondly, this work has contributed towards improving steganographic security by providing new features: the coordinate location and semantic meaning of the object

Wireless sensor networks

Wireless sensor networks promise an unprecedented fine-grained interface between the virtual and the physical world. They are one of the most rapidly developing new information technologies, with applications in a wide range of fields including industrial process control, security and surveillance, environmental sensing, and structural health monitoring. The subject of this project is motivated by the urgent need to provide a comprehensive and organized survey of the field. It shows how the core challenges of energy efficiency, robustness, and autonomy are addressed in these systems by networking techniques across multiple layers. The topics covered include network deployment, wireless characteristics, time synchronization, congestion and error control, medium access, standards, topology control, routing, security, data transfer, transport protocols and new technologies and materials in fabricating sensors

Effects of Y_(2)O_(3) and α-ZrP Additives on Lubrication of Grease

Development of novel additives in lubricants is a promising approach for high performance and energy saving devices. Those include automotive, marine, and wind turbines. In a wind turbine, the unplanned break-down rate of bearings caused by improper lubricants is 40% ~50%. The objective of this research is to 1) develop novel nanomaterials as grease additives, and 2) obtain understanding in tribological performances of the same. The research focuses on zirconium phosphate and yttrium oxide nanoparticles as additives in grease. Experimental approach is used to investigate the effects of those nanomaterials on lubrication of grease. Experiments such as tribological experiments at room and elevated temperatures, galling resistance tests, and characterization of worn surfaces will be conducted. Characterization includes optical microscope, interferometer, and scanning electron microscope (SEM). Results showed that the addition of nanoparticles induced reduction of coefficient of friction. In addition, the wear rate of the test samples was reduced by adding nanoparticles. This research investigates the effects of nanoparticles with unique shape and structure and develops understating in mechanisms. The research results will be beneficial to the application of lubricants for high performance and efficiency. This thesis contains six chapters. Chapter I is the background information about tribology and materials needed to understand this research. Chapter II describes the motivation and objectives. Chapter III discusses the experimental procedures and materials used in this research. Chapter IV and V present and discuss the results obtained from yttrium oxide and zirconium phosphate, respectively. Chapter VI discusses the major conclusions obtained from the results and offers suggestions for future work

Tsunamis from source to coast

Tsunami disasters pose a significant threat to coastal communities. In the last decades, tsunamis caused enormous destruction and exceeding 250000 fatalities. International efforts led to sig-nificant advances in tsunami science and research, but recent events demonstrated some limi-tations. Thus, it is essential to increase our knowledge of the source to coast tsunami phenom-enon. A better understanding of potential tectonic structures and other generation mechanisms is needed, especially in complex geologic domains or where sources are unknown. Furthermore, we need to improve Tsunami Warning Systems (TWSs) to provide timely alerts for communi-ties in the near field. Therefore, potential tsunamigenic sources in the diffuse plate boundary setting and the near field of the southwest Iberian margin (SWIM) are investigated. For the March 31, 1761, trans-atlantic tsunami, numerical modelling has been used to propose a structure that agrees with tsunami travel times, tsunami observations, macroseismic data, and kinematic plate modelling. Since there exists a description of a tsunami for the November 11, 1858, Sétubal earthquake, its source has been investigated using macroseismic analysis. The analysis suggests a local structure in a compressive regime with weak to moderate tsunamigenic potential. Future tsu-nami hazard assessments need to include the sources of the investigated events. To quickly estimate the tsunami impact, the Tsunami Runup Predictor (TRP), an empirical source-to-coast method to instantly provide first-order estimates of the tsunami runup based on waveform parameters has been developed. The TRP is helpful for emergency managers and evacuation planning for near-field events. Moreover, the author of this thesis contributed to the tsunami impact assessment of September 28, 2018, Palu tsunami, where tsunamis generated by multiple sources caused runup heights up to 9.2 m. However, for local sources, tsunami warning remains challenging; thus, communities need to be prepared how to respond appropriately to earthquakes and tsunamis with or without warning