LIMOFilling: Local Information Guide Hole-Filling and Sharp Feature Recovery for Manifold Meshes

Manifold mesh, a triangular network for representing 3D objects, is widely used to reconstruct accurate 3D models of objects structure. The complexity of these objects and self-occlusion, however, can cause cameras to miss some areas, creating holes in the model. The existing hole-filling methods do not have the ability to detect holes at the model boundaries, leaving overlaps between the newly generated triangles, and also lack the ability to recover missing sharp features in the hole-region. To solve these problems, LIMOFilling, a new method for filling holes in 3D manifold meshes was proposed, and recovering the sharp features. The proposed method, detects the boundary holes robustly by constructing local overlap judgments, and provides the possibility for sharp features recovery using local structure information, as well as reduces the cost of maintaining manifold meshes thus enhancing their utility. The novel method against the existing methods have been tested on different types of holes in four scenes. Experimental results demonstrate the visual effect of the proposed method and the quality of the generated meshes, relative to the existing methods. The proposed hole-detection algorithm found almost all of the holes in different scenes and qualitatively, the subsequent repairs are difficult to see with the naked eye.

‘Velvet Triangles’ in Women, Peace and Security Agenda in Indonesia

Resolution 1325 on Women, Peace and Security (WPS Agenda) has been recognized as a landmark in the history of global efforts to maintain international peace and security by centering women on the agenda. Indonesia has shown its commitment to WPS Agenda by adopting its first National Action Plan (NAP) in 2014. On top of that, Indonesia is also committed to increasing the number of female peacekeepers in the UN peacekeeping missions. This research aims to examine how WPS Agenda as a global normative framework diffuses and is internalized in Indonesia. This research employed a feminist institutionalist approach and a qualitative method. Using the concept of ‘velvet triangles’ by Alison Woodward (2004) as our theoretical framework, we argue that the triangular network of velvet actors—consisting of feminist bureaucrats, civil society organizations’ activists, and gender experts—plays a critical role in making a considerably important space for the diffusion of WPS Agenda within Indonesia’s domestic politics and foreign policy debates. In concluding the article, we propose two considerations taking into account the formal and informal arrangement of the velvet constellation and the transnational scale of the network’s actors to provide a more nuanced conceptual definition of velvet triangles.

Algorithms for Delivery of Data by Drones in an Isolated Area Divided into Squares

Drones are frequently used for the delivery of materials or other goods, and to facilitate the capture and transmission of data. Moreover, drone networks have gained significant interest in a number of scenarios, such as in quarantined or isolated areas, following technical damage due to a disaster, or in non-urbanized areas without communication infrastructure. In this context, we propose a network of drones that are able to fly on a map covered by regular polygons, with a well-established mobility schedule, to carry and transfer data. Two means exist to equidistantly cover an area with points, namely, grouping the points into equilateral triangles or squares. In this study, a network of drones that fly in an aerial area divided into squares was proposed and investigated. This network was compared with the case in which the area is divided into equilateral triangles. The cost of the square drone network was lower than that of the triangular network with the same cell length, but the efficiency factors were better for the latter. Two situations related to increasing the drone autonomy using drone charging or battery changing stations were analyzed. This study proposed a Delay Tolerant Network (DTN) to optimize the transmission of data. Multiple simulation studies based on experimental flight tests were performed using the proposed algorithm versus five traditional DTN methods. A light Wi-Fi Arduino development board was used for the data transfer between drones and stations using delivery protocols. The efficiency of data transmission using single-copy and multiple-copy algorithms was analyzed. Simulation results showed a better performance of the proposed Time-Dependent Drone (TD-Drone) Dijkstra algorithm compared with the Epidemic, Spray and Wait, PRoPHET, MaxProp, and MaxDelivery routing protocols.

Impact of damage on the propagation of Rayleigh waves in lattice materials

We analyze in this contribution the phase velocities of Rayleigh waves in periodic beam-lattices materials. The effective mechanical properties for the virgin and damaged structures are evaluated. The damaged lattice is modeled by removing beams within full networks made of repetitive unit cells. An evaluation of the phase velocities for the longitudinal and transverse versus the amount of damage is done for different relative densities evaluated versus the percentage of damaged beams for the square and triangular network. The effective mechanical properties of the overall network are evaluated as a function of the increasing damage based on a numerical procedure. Computations show that the square lattice has higher phase velocities in comparison with the triangular lattice. This work sets the basis of a methodology for evaluating the state of damage in network materials based on the changes in the wave propagation velocities.