3,485 research outputs found
Autonomous Network Defence Using Multi-Agent Reinforcement Learning and Self-Play
Early threat detection is an increasing part of the cybersecurity landscape, given the growing scale and scope of cyberattacks in the recent years. Increasing exploitation of software vulnerabilities, especially in the manufacturing sector, demonstrates the ongoing need for autonomous network defence. In this work, we model the problem as a zero-sum Markov game between an attacker and defender reinforcement learning agents. Previous methods test their approach on a single topology or limit the agents to a subset of the network. However, real world networks are rarely fixed and often add or remove hosts based on demand, link failures, outages, or other factors. We do not confine our research to a fixed network in terms of size and topology, but instead are interested in larger networks and varied topologies to determine the scalability and robustness of the approach. We consider additional topologies and a robust training curriculum that incorporates network topologies to build more general, capable agents. We also use PPO which offers a good balance of computational complexity and convergence speed
Effects of the passage of Comet C/2013 A1 (Siding Spring) observed by the Shallow Radar (SHARAD) on Mars reconnaissance orbiter
The close passage of Comet C/2013 A1 (Siding Spring) to Mars provided a unique opportunity to observe the interaction of cometary materials with the Martian ionosphere and atmosphere using the sounding radar SHARAD (SHAllow RADar) aboard Mars Reconnaissance Orbiter. In two nightside observations, acquired in the 10 h following the closest approach, the SHARAD data reveal a significant increase of the total electron content (TEC). The observed TEC values are typical for daylight hours just after dawn or before sunset but are unprecedented this deep into the night. Results support two predictions indicating that cometary pickup O+ ions, or ions generated from the ablation of cometary dust, are responsible for the creation of an additional ion layer
Socioeconomic differentiation, leadership, and residential patterning at an Araucanian chiefly center (Isla Mocha, AD 1000-1700)
The native populations of Araucania (southern Chile) never succumbed to Inka or Spanish conquest. But while independent indigenous sociopolitical structures persisted until the late 1800s, remarkably little is known about late prehispanic and early historical Araucanian sociopolitical organization. Lacking significant archaeological research, current reconstructions are based almost exclusively on European chronicles, and paint a bewilderingly varied picture of indigenous organization, ranging from a native Araucania made up of scattered autonomous kin units lacking any political centralization, to one consisting of powerful chiefdoms built on elaborate public display and macro-regional alliances among elites.
My research was oriented at producing a comprehensive understanding of Araucanian settlement and socioeconomic organization and social leadership through archaeological investigation of household variability and intra-community patterning at archaeological sites belonging to the El Vergel archaeological complex (AD 1000-1550) and subsequent historical reche-Mapuche (AD 1550- 1750) period. My research zone of 6 km2 was established in and around the site of P31-1, an ethnohistorically tentative chiefly center, on Isla Mocha (Chile). In this zone, a full coverage survey, intensive surface collections, and test pits were completed. Inter and intrasite analyses were made of ceramic, lithic, archaeobotanical, and faunal assemblages. The information gathered made possible assessment of several current constructs of native Araucanian sociopolitical organization.
The fieldwork revealed the existence of three communities (sites P29-1, P31-1, and P5-1), which were relatively autonomous socially and economically. If there indeed was a paramount chief at P31-1, the centralizing effects of this office were very weak. The research produced no evidence for social inequality based on wealth finance activities (in exchange or craft production), wealth accumulation, or even markedly different household activities. At both P29-1 and P31-1 excavations revealed small but pervasive wealth differences among residents, seen in variability in consumption of higher value pottery, better stone tool material, and in diet. These muted wealth differences, when combined with the presence of two mounds and a sizable platform, suggest patterns of native social differentiation and leadership based on prestige and ideology, rather than forms of economic control
Are Consumers Willing to Pay More for Biodegradable Containers Than for Plastic Ones? Evidence from Hypothetical Conjoint Analysis and Nonhypothetical Experimental Auctions
This study used and compared hypothetical conjoint analysis and nonhypothetical experimental auctions to elicit floral customers’ willingness to pay for biodegradable plant containers. The results of the study show that participants were willing to pay a price premium for biodegradable containers, but the premium is not the same for different types of containers. This article also shows the mixed ordered probit model generates more accurate results when analyzing the conjoint analysis Internet survey data than the ordered probit model.biodegradable, willingness to pay, marketing, carbon footprint, waste composition, green industry, nursery crops, floriculture crops, Agribusiness, Agricultural and Food Policy, Environmental Economics and Policy, Financial Economics, Food Consumption/Nutrition/Food Safety, Marketing, Public Economics, Research and Development/Tech Change/Emerging Technologies, D12, Q13,
Complications with Controlling Insect Eggs
Eggs are difficult to kill because of the unique structure of the eggshell, comprised of multiple layers that have evolved to allow the embryo to breathe while simultaneously limiting water loss. The eggshell has been shown to be an excellent barrier to insecticides, fungal pathogens, and some fumigants. The insect eggshell contains only a few areas that could allow penetration of insecticides, the aeropyles and micropyles, which seem to be either so few in number or small in size that they do not allow a sufficient amount of insecticide through the eggshell. Resistance is also a contributing factor to control failures of insect eggs. Resistance in eggs has been documented in several insect species and a few studies have shown that some insect eggs produce elevated numbers of enzymes to break down insecticides. This chapter focuses on the structure and respiration of the insect eggshell as a barrier to insecticides and also covers various management strategies against insect eggs. Lastly, we discuss the few documentations of resistance in insect eggs thus far
SHARAD radar sounding of the Vastitas Borealis Formation in Amazonis Planitia
Amazonis Planitia has undergone alternating episodes of sedimentary and volcanic infilling, forming an interleaved sequence with an upper surface that is very smooth at the kilometer scale. Earlier work interprets the near-surface materials as either young, rough lava flows or ice-rich sediment layers, overlying a basement comprising the Vastitas Borealis Formation and earlier Hesperian plains. Sounding radar profiles across Amazonis Planitia from the Shallow Radar (SHARAD) instrument on the Mars Reconnaissance Orbiter reveal a subsurface dielectric interface that increases in depth toward the north along most orbital tracks. The maximum depth of detection is 100–170 m, depending upon the real dielectric permittivity of the materials, but the interface may persist at greater depth to the north if the reflected energy is attenuated below the SHARAD noise floor. The dielectric horizon likely marks the boundary between sedimentary material of the Vastitas Borealis Formation and underlying Hesperian volcanic plains. The SHARAD-detected interface follows the surface topography across at least one of the large wrinkle ridges in north central Amazonis Planitia. This conformality suggests that Vastitas Borealis sediments, at least in this region, were emplaced prior to compressional tectonic deformation. The change in radar echo strength with time delay is consistent with a loss tangent of 0.005–0.012 for the column of material between the surface and the reflector. These values are consistent with dry, moderate-density sediments or the lower end of the range of values measured for basalts. While a component of distributed ice in a higher-loss matrix cannot be ruled out, we do not find evidence for a dielectric horizon within the Vastitas Borealis Formation that might suggest an abrupt change from an upper dry layer to an ice-rich lower deposit
Four-lepton production at hadron colliders: aMC@NLO predictions with theoretical uncertainties
We use aMC@NLO to study the production of four charged leptons at the LHC,
performing parton showers with both HERWIG and Pythia6. Our underlying matrix
element calculation features the full next-to-leading order
result and the contribution of the channel, and it
includes all off-shell, spin-correlation, virtual-photon-exchange, and
interference effects. We present several key distributions together with the
corresponding theoretical uncertainties. These are obtained through a
process-independent technique that allows aMC@NLO to compute scale and PDF
uncertainties in a fully automated way and at no extra CPU-time costComment: 24 pages, 6 figure
Plan de marketing para la bebida Bio Camu de AJEPER S.A.
El presente trabajo tiene como objetivo realizar el plan de marketing para un nuevo producto del grupo AJE llamado BIO Camu. En primer lugar, hicimos análisis del ambiente interno, seguido por uno de recursos, VRIO (valor, rareza, imitabilidad y organización); y del macro y micro ambiente. Estos análisis nos sirvieron para identificar los principales atributos de AJEPER S.A., así como factores que resaltaron en cuanto a fortalezas, debilidades, oportunidades y amenazas. Luego, se investigó al cliente, para entender la percepción de los consumidores. Para ello, se utilizó una metodología de tipo cualitativo y cuantitativo. La primera, consistió en trabajar con dos grupos focales. La parte cuantitativa consistió en elaborar una encuesta para conocer el atractivo del producto en el mercado peruano de bebidas saludables. Asimismo, diseñamos un canal de Marketing mix. Finalmente, se calculó una proyección de ventas de 3,460,500 unidades anuales. En conclusión, el proyecto se calificó como viable para AJE
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