Topology optimization of multiple anisotropic materials, with application to self-assembling diblock copolymers

We propose a solution strategy for a multimaterial minimum compliance topology optimization problem, which consists in finding the optimal allocation of a finite number of candidate (possibly anisotropic) materials inside a reference domain, with the aim of maximizing the stiffness of the body. As a relevant and novel application we consider the optimization of self-assembled structures obtained by means of diblock copolymers. Such polymers are a class of self-assembling materials which spontaneously synthesize periodic microstructures at the nanoscale, whose anisotropic features can be exploited to build structures with optimal elastic response, resembling biological tissues exhibiting microstructures, such as bones and wood. For this purpose we present a new generalization of the classical Optimality Criteria algorithm to encompass a wider class of problems, where multiple candidate materials are considered, the orientation of the anisotropic materials is optimized, and the elastic properties of the materials are assumed to depend on a scalar parameter, which is optimized simultaneously to the material allocation and orientation. Well-posedness of the optimization problem and well-definition of the presented algorithm are narrowly treated and proved. The capabilities of the proposed method are assessed through several numerical tests

Trojans in Early Design Steps—An Emerging Threat

Hardware Trojans inserted by malicious foundries during integrated circuit manufacturing have received substantial attention in recent years. In this paper, we focus on a different type of hardware Trojan threats: attacks in the early steps of design process. We show that third-party intellectual property cores and CAD tools constitute realistic attack surfaces and that even system specification can be targeted by adversaries. We discuss the devastating damage potential of such attacks, the applicable countermeasures against them and their deficiencies

The Evolution of First Person Vision Methods: A Survey

The emergence of new wearable technologies such as action cameras and smart-glasses has increased the interest of computer vision scientists in the First Person perspective. Nowadays, this field is attracting attention and investments of companies aiming to develop commercial devices with First Person Vision recording capabilities. Due to this interest, an increasing demand of methods to process these videos, possibly in real-time, is expected. Current approaches present a particular combinations of different image features and quantitative methods to accomplish specific objectives like object detection, activity recognition, user machine interaction and so on. This paper summarizes the evolution of the state of the art in First Person Vision video analysis between 1997 and 2014, highlighting, among others, most commonly used features, methods, challenges and opportunities within the field.Comment: First Person Vision, Egocentric Vision, Wearable Devices, Smart Glasses, Computer Vision, Video Analytics, Human-machine Interactio

Du loup. Force et loi

For elucidating the relation between violence and justice, that gives rise to the phrase «force of law», the figure of wolf, the lupus in fabula, occupies a strategic place in the western philosophical and political discourse. The double reading –or writing– of such a phrase in a text by Solon, because of a lapsus calami – indeed a masterly slip of the pen, as Derrida reminds us– allows us to see the –paradoxical– double face of the sovereign kratos: that of force without law and outside the law that establishes the law, and that of force incorporated into the law to accomplish justice. The figure of the wolf embodies this paradox of sovereignty.Para esclarecer la relación entre violencia y justicia que cristaliza en el sintagma «fuerza de ley», la figura del lobo, el lupus in fabula, ocupa un lugar estratégico en el discurso filosófico-político de occidente. La doble lectura –o escritura– de dicho sintagma en un texto de Solón debida a un lapsus calami –lapsus magistral sin duda, como recuerda Derrida– nos permite ver la doble cara –paradójica– del kratos soberano: la de la fuerza sin ley y fuera de la ley que establece la ley, y la de la fuerza incorporada a la ley para la realización de la justicia. En la figura del lobo se encarna esa paradoja de la soberanía.Para esclarecer la relación entre violencia y justicia que cristaliza en el sintagma «fuerza de ley», la figura del lobo, el lupus in fabula, ocupa un lugar estratégico en el discurso filosófico-político de occidente. La doble lectura –o escritura– de dicho sintagma en un texto de Solón debida a un lapsus calami –lapsus magistral sin duda, como recuerda Derrida– nos permite ver la doble cara –paradójica– del kratos soberano: la de la fuerza sin ley y fuera de la ley que establece la ley, y la de la fuerza incorporada a la ley para la realización de la justicia. En la figura del lobo se encarna esa paradoja de la soberanía

Left/Right Hand Segmentation in Egocentric Videos

Wearable cameras allow people to record their daily activities from a user-centered (First Person Vision) perspective. Due to their favorable location, wearable cameras frequently capture the hands of the user, and may thus represent a promising user-machine interaction tool for different applications. Existent First Person Vision methods handle hand segmentation as a background-foreground problem, ignoring two important facts: i) hands are not a single "skin-like" moving element, but a pair of interacting cooperative entities, ii) close hand interactions may lead to hand-to-hand occlusions and, as a consequence, create a single hand-like segment. These facts complicate a proper understanding of hand movements and interactions. Our approach extends traditional background-foreground strategies, by including a hand-identification step (left-right) based on a Maxwell distribution of angle and position. Hand-to-hand occlusions are addressed by exploiting temporal superpixels. The experimental results show that, in addition to a reliable left/right hand-segmentation, our approach considerably improves the traditional background-foreground hand-segmentation

Practice-based methodology for effectively modeling and documenting search, protection and innovation

AbstractThis work relates to a methodology for effectively modeling an Action and Problem System and documenting a path built by means of patent databases. The aim of this work is to provide an improved method and operative tool for a quick and reliable patents investigation driven by Boolean algorithms. The method has been tested with several projects for companies of different industrial areas. Moreover in the last months the method has been used in case studies by students from the University of Bergamo with good results after a very few hours of training. Two specific case studies will be discussed in this paper in order to clarify the operative value of said method and to show the results obtained in terms of solutions found and of efforts requested

Unsupervised Understanding of Location and Illumination Changes in Egocentric Videos

Wearable cameras stand out as one of the most promising devices for the upcoming years, and as a consequence, the demand of computer algorithms to automatically understand the videos recorded with them is increasing quickly. An automatic understanding of these videos is not an easy task, and its mobile nature implies important challenges to be faced, such as the changing light conditions and the unrestricted locations recorded. This paper proposes an unsupervised strategy based on global features and manifold learning to endow wearable cameras with contextual information regarding the light conditions and the location captured. Results show that non-linear manifold methods can capture contextual patterns from global features without compromising large computational resources. The proposed strategy is used, as an application case, as a switching mechanism to improve the hand-detection problem in egocentric videos.Comment: Submitted for publicatio

Tracking Using Continuous Shape Model Learning in the Presence of Occlusion

This paper presents a Bayesian framework for a new model-based learning method, which is able to track nonrigid objects in the presence of occlusions, based on a dynamic shape description in terms of a set of corners. Tracking is done by estimating the new position of the target in a multimodal voting space. However, occlusion events and clutter may affect the model learning, leading to a distraction in the estimation of the new position of the target as well as incorrect updating of the shape model. This method takes advantage of automatic decisions regarding how to learn the model in different environments, by estimating the possible presence of distracters and regulating corner updating on the basis of these estimations. Moreover, by introducing the corner feature vector classification, the method is able to continue learning the model dynamically, even in such situations. Experimental results show a successful tracking along with a more precise estimation of shape and motion during occlusion events

New sulfurated derivatives of cinnamic acids and rosmaricine as inhibitors of STAT3 and NF-kappa B transcription factors

A set of new sulfurated drug hybrids, mainly derived from caffeic and ferulic acids and rosmaricine, has been synthesized and their ability to inhibit both STAT3 and NF-kappa B transcription factors have been evaluated. Results showed that most of the new hybrid compounds were able to strongly and selectively bind to STAT3, whereas the parent drugs were devoid of this ability at the tested concentrations. Some of them were also able to inhibit the NF-kappa B transcriptional activity in HCT-116 cell line and inhibited HCT-116 cell proliferation in vitro with IC50 in micromolar range, thus suggesting a potential anticancer activity. Taken together, our study described the identification of new derivatives with dual STAT3/NF-kappa B inhibitory activity, which may represent hit compounds for developing multi-target anticancer agents