The loads generated inside agricultural silos under static and dynamic conditions depend on the mechanical properties of the materials stored inside them. The silo calculation methodologies are based on these mechanical properties. Although it is known that moisture content greatly influences the values reached by these mechanical properties, just few studies have been conducted to determine them. The present work determines the angle of internal friction, the apparent cohesion, the dilatancy angle and the apparent specific weight of wheat when subjected to different moisture contents. Direct shear and oedometer assay devices were used. In addition, a climatic chamber was used to moisten the wheat samples used in this work. The moisture content applied to the samples ranged from 7.5% to 15.5%. From the different assays carried out it could be observed that the values of the angle of internal friction and apparent cohesion obtained from direct shear assays, as well as those related to the apparent specific weight obtained from oedometer assays were like those found in the literature. The apparent specific weight increased as moisture content increased, reaching a peak value at a moisture content of 13.4%, followed by a drop at a moisture content of 15.5%. The values here provided can be used in silo load calculations involving numerical methods.

The Stirling engine is a simple type of external-combustion engine with an external combustion engine based on cyclic compression and expansion of gas at different temperature levels. It has high efficiency; low vibration levels, simple structure and can run on any combustible fuels. It has been the object of numerous studies. This paper presents an analysis of a Stirling engine model GENOA 03 for electric power generation, of 3 KW of nominal power with pressurized air as working fluid, currently under development. To improve its performance and ensure a good operational reliability, it is necessary to carry out a modelling of the engine in all its operating range. This requires complex numerical models that simulate the behaviour of any element of the engine in a cycle. Two typologies of thermodynamic models are developed in this work: isothermal and adiabatic. The main benefits and shortcomings of each model are mentioned. The geometry and conditions of the engine have been adapted through the Matlab ® tool, in order to obtain the operative conditions of the cooler that you want to replace, as well as an approximation to the expected behaviour.

We study the propagation of a particular field that we call Gaussian-top-hat that presents self-focusing and maintains its shape for some propagation distances.

This manuscript presents a system that can generate a 2D grid map and a 3D voxel model of an environment by fusing multiple sensors integrated into a robot. The fusion of these sensors is done by utilizing Robot Operating System (ROS) and some of its libraries. The sensors that are fused in the robot are a Light Detection and Ranging (LIDAR), Inertial Measurement Units (IMU), wheel encoders, and a Time-of-Flight camera. With the fusion of the point cloud data information obtained with the Time-of-Flight camera, the laser information of the LIDAR sensor, in addition to the odometry generated with the other sensors, a 2D grid map and a 3D model of two different environments were created, thus testing the performance of the system.

We present a new family of Bessel solutions of the paraxial equation. Such solutions keep their form during propagation due to a quadratic phase factor that makes them scaled propagation invariant fields. The Bessel beams we introduce have the particularity that the topological phase is twice the order of the Bessel function and the argument varies quadratically with the radius

The Iberian wolf (Canis lupus signatus) is recolonizing historical distribution areas after decades of absence. As in other human-dominated landscapes, finding a balance to protect this species by favoring recolonization and mitigating human-wildlife conflicts is a challenge. Since wolves are often generalist opportunistic predators, we studied their diet composition in the Central Spain to evaluate the consumption of domestic ungulates and provide reliable data that help local authorities to deal with the current wolf-cattle ranchers conflict and coexistence. Diet composition (% prey occurrence, % prey ingested biomass) was analyzed through the identification of prey hairs present in 671 scats collected between 2017 and 2021. Wolves fed more on wild ungulates (82% occurrence) than domestic ones (18%). Wild boar (Sus scrofa, 44% occurrence) and roe deer (Capreolus capreolus, 35%) were the most consumed prey. Wolves positively selected these two species. The wolf's diet varied between seasons, years, and forest regions, but a diet based on wild ungulates predominated over domestic ones. Food niche breadth and showed variations depending on seasons and years. Preserving the availability and diversity of wild ungulates may favor reducing livestock attacks and would be an achievable goal that help to conserve this species and reduce conservation conflicts.