Outline of the Solar System: Activities for elementary students

An introduction to the solar system for the elementary school student is given. The introduction contains historical background, facts, and pertinent symbols concerning the sun, the nine major planets and their moons, and information about comets and asteroids. Aids to teaching are given, including a solar system crossword puzzle with answers

Targeted Browsing with Goats for Eastern Redcedar (Juniperus Virginiana L.) Control

As eastern redcedar (ERC) (Juniperus virginiana L.) grassland encroachment progresses, all potential control methods should be explored in the interest of Great Plains grassland health and longevity. Targeted browsing with goats has been proven as an effective control method on some juniper species; however, little is known about its ability to control ERC. These studies intend to mend knowledge gaps of how targeted browsing with goats control ERC by causing tree death without chemicals or machinery. The first study is two 3x3 Latin squares comparing protein-supplemented diets. The second study is a randomized complete block design of five 0.224 ha sites over two years, each with four replicate paddocks. Trees of five height classes were tagged (n = 820) and measured before and after browsing. The objectives were to quantify and to characterize targeted browsing with goats as ERC biological control in terms of 1) the efficacy of ruminally undegradable protein (RUP) supplementation to aid goats in detoxifying plant secondary metabolites (PSM) when browsing ERC bark and foliage, 2) browsing in relation to tree height, and 3) subsequent tree mortality. We hypothesized that 1) RUP protein supplemented goats will defoliate and debark ERC more than the control, 2) goats will debark ERC \u3e 100 cm tall and defoliate ERC \u3c 100 cm tall, and 3) debarked ERC will more frequently be killed than defoliated ERC. Supplementation did not (P \u3e 0.05) increase browsing compared to the control. Unlike previous pen feeding trials that studied select fed tree parts, we investigated goat behavior on whole ERC. In the field study, tree height was correlated positively with debarking and negatively with defoliation (P \u3c 0.001). The resulting mortality was positively correlated with the taller, debarked trees (P \u3c 0.001), and sites with less deciduous browse appeared to have more debarking suggesting that juniper should ideally be the only woody component when applying targeted browsing. The results of both studies have practical implications for herdsman and landowners including suggested stocking rate, considerations for site vegetation, expected juniper mortality, and recommendations for future research

Quantum entanglement between a nonlinear nanomechanical resonator and a microwave field

We consider a theoretical model for a nonlinear nanomechanical resonator coupled to a superconducting microwave resonator. The nanomechanical resonator is driven parametrically at twice its resonance frequency, while the superconducting microwave resonator is driven with two tones that differ in frequency by an amount equal to the parametric driving frequency. We show that the semi-classical approximation of this system has an interesting fixed point bifurcation structure. In the semi-classical dynamics a transition from stable fixed points to limit cycles is observed as one moves from positive to negative detuning. We show that signatures of this bifurcation structure are also present in the full dissipative quantum system and further show that it leads to mixed state entanglement between the nanomechanical resonator and the microwave cavity in the dissipative quantum system that is a maximum close to the semi-classical bifurcation. Quantum signatures of the semi-classical limit-cycles are presented.Comment: 36 pages, 18 figure

Case Study: Cooling Channels for Material Testing Applications Using Laser Powder Bed Fusion

Additive Manufacturing continues to gain a reputation as a key technology that will have a major impact on all aspects of mechanical engineering. The United States Air Force’s (USAF) Air Force Institute of Technology (AFIT), based in Dayton, Ohio, has expanded its AM-focused education and R&D capabilities with the purchase of a Laser Powder Bed Fusion system from Germany’s Concept Laser

Optimal strategies for a game on amenable semigroups

The semigroup game is a two-person zero-sum game defined on a semigroup S as follows: Players 1 and 2 choose elements x and y in S, respectively, and player 1 receives a payoff f(xy) defined by a function f from S to [-1,1]. If the semigroup is amenable in the sense of Day and von Neumann, one can extend the set of classical strategies, namely countably additive probability measures on S, to include some finitely additive measures in a natural way. This extended game has a value and the players have optimal strategies. This theorem extends previous results for the multiplication game on a compact group or on the positive integers with a specific payoff. We also prove that the procedure of extending the set of allowed strategies preserves classical solutions: if a semigroup game has a classical solution, this solution solves also the extended game.Comment: 17 pages. To appear in International Journal of Game Theor

The Impact of Laser Control on The Porosity And Microstructure of Selective Laser Melted Nickel Superalloy 718

Additively manufacturing high performance metals by laser processing represents an exciting opportunity to exploit localized properties by varying input parameters throughout the process. This work explores the solidification and microstructural properties of selectively laser melted (SLM) Inconel 718 (IN718) using unique processing parameters. By employing traditional pulsed laser physics techniques, samples were manufactured with a continuous wave laser to study a potential ubiquitous approach. While the overall power density was controlled, the power, speed, and hatch spacing were varied. The porosity and grain sizes of the samples were characterized by optical and scanning electron microscopes. The influence of processing parameters showed physical differences in the final samples. Sample degradation was observed in higher power processes with porosity up 10%, likely due to increased temperatures and more intense thermal gradients

Association of microsomal epoxide hydrolase polymorphisms and lung cancer risk

lung cancer ris