Estimation of Optimal Flight Trajectory in a Total Power Loss Scenario Using Proximal Policy Optimization

Recent research has been conducted in using deep reinforcement learning algorithms to generate closed form optimal control laws for helicopters in power loss scenarios. The control laws could allow for design of various cockpit visual pilot aids if proven successful. Such pilot aids are predicted to reduce pilot workload during execution of an emergency powerless landing, and to overall increase the probability of landing safely in such an event. The proposed topic discusses the use of the PPO algorithm in order to find an optimal control policy for a helicopter in a total power loss emergency landing scenario. The task consists of designing and training an actor neural network and a critic neural network using the PPO algorithm, along with developing the dynamic equations of motion for the helicopter, defining a reward structure and tweaking relevant hyper-parameters. The PPO algorithm has been proven overall feasible for bringing a simplistically modeled helicopter to safe landings over a wide range of initial flight conditions

Del Estado de bienestar al modelo neoliberal : la vivienda social en el caso chileno (dossier)

Este artículo de investigación recorre poco más de un siglo de políticas de vivienda de interés social en Chile desde la promulgación de la Ley de habitaciones obreras en 1906 hasta la actualidad. Del modelo asistencialista que trataba a la vivienda como un acto de caridad a fines del siglo XIX y en las primeras décadas del siglo XX, Chile pasó a un Estado de Bienestar que se extiende, con variantes más o menos desarrollistas, por varias décadas hasta que el gobierno de Pinochet (1973-1990) impondrá el modelo económico neoliberal que cambiará radicalmente los paradigmas urbanos y sociales. Desde el regreso a la democracia en 1990, Chile cuestiona el modelo y continúa ensayando –cual laboratorio experimental– la forma de superar sus contradicciones sin perder los avances logrados en el siglo XX.This article covers around a century of social interest housing policies in Chile from the Workers’ Housing Law in 1906 to the present day. From the Welfare model that deal the housing as an act of charity during the 19th century up to the first decades of the 20th century, Chile passed into a welfare state that extended, with variations, for several decades until the Pinochet government (1973.1990) will impose the neoliberal economic model that will radically change urban and social paradigms. From the return of democracy, Chile is searching the way to overcome its contradictions without losing the century XX achievements

A COMPERATIVE STUDY ON NITROEENOUS AND BIOFERTILIZER ON GROWTH AND YIElD OF MUNGBEAN

A Thesis Submiued to the Faculty of Agriculture, Sher-e-Bangra Agriculiural University, Dhaka-1207 in part fulfillment of requirements for the degree of MASTER OF SCIENCE (M.S.) IN AGRICULTURAL CHEMISTRY SEMESTER: JANUARY-JUNE'11The experiment was conducted at the Research Farm of Sher-e-Bangla Agricultural University (SAU). Dhaka during the period from April 2011 to July 2011 to study the performance of two mungbean varieties without Bradyrhizobiuzn and with nitrogen/Bradyrhizobiurn. There were six treatment combinations and four replications were laid out in Randomized Complete Block Design (RCBD) technique. The Bradyrhizobiurn strain BARI RVr-403 was used for the above experiment. The selected varieties were BARI Mung-5 and BARI Mung-6. The above varieties were tested with or without nitrogenlBradvrhizohiwn inoculation. BARI Mung-5 performed better than BARI Mung-6 variety in respect of different parameters like nodule number and weight, root weight and shoot weight, root length and shoot length, pod length and pods plant'. But BARI Mung-6 produced higher 1000-seed weight, stover yield, seed yield, plant height and seeds pod' than BARI Mung-5. Bradyrhizohiurn inoculation significantly increased nodule number and weight. seed yield, stover yield, plant height. 1000-seed weight, pods plant* seeds pod'. N content in seed and stover, N uptake by stover and seed. Interaction ellects revealed that BARI Mung-5 with Bracs5.'rhizohium inoculation recorded the highest nodulation but inoculated BARI Mung-6 recorded the highest seed yield compared to other treatment combinations. Non-inoculated BARI Mung-5 gave the lowest yield. The highest N uptake by seed and stover was found in BARI Mung-6 x Inoculum treated plot. Economic analysis revealed that the highest BCR (1.31) was noted in inoculated BARI Mung-5

Desarrollo económico y desarrollo urbano: una aleación ineludible

Este artículo aborda la relación entre espacio urbano y desarrollo económico, social y político centrándose en cinco factores indispensables para lograr calidad de vida a través de un desarrollo sustentable: la participación ciudadana, la gobernabilidad de la ciudad, el espacio público, los instrumentos de planificación y la infraestructura

Diabetic retinopathy: current and future methods for early screening from a retinal hemodynamic and geometric approach

Diabetic retinopathy (DR) is a major disease and is the number one cause of blindness in the UK. In England alone, 4200 new cases appear every year and 1280 lead to blindness. DR is a result of diabetes mellitus, which affects the retina of the eye and specifically the vessel structure. Elevated levels of glucose cause a malfunction in the cell structure, which affects the vessel wall and, in severe conditions, leads to their breakage. Much research has been carried out on detecting the different stages of DR but not enough versatile research has been carried out on the detection of early DR before the appearance of any lesions. In this review, the authors approach the topic from the functional side of the human eye and how hemodynamic factors that are impaired by diabetes affect the vascular structur

Varroa mite evolution: a neglected aspect of worldwide bee collapses?

While ectoparasitic Varroa mites cause minimal damage to their co-evolved ancestral host, the eastern honey bee (Apis cerana), they devastate their novel host, the western honey bee (Apis mellifera). Over several decades, the host switch caused worldwide population collapses, threatening global food security. Varroa management strategies have focused on breeding bees for tolerance. But, can Varroa overcome these counter-adaptations in a classic coevolutionary arms race? Despite increasing evidence for Varroa genetic diversity and evolvability, this eventuality has largely been neglected. We therefore suggest a more holistic paradigm for studying this host-parasite interaction, one in which \u27Varroa-tolerant\u27 bee traits should be viewed as a shared phenotype resulting from Varroa and honey bee interaction