Design of a Lighter than Air Vehicle that Achieves Positive Buoyancy in Air Using a Vacuum

Three designs for a Lighter Than Air (LTA) structure that achieve positive buoyancy using a vacuum in place of a lifting gas were proposed and evaluated. The ratio of structure weight to the weight of displaced air was termed Weight/Buoyant Force (W/B) where a W/B1 corresponds to positive buoyancy. Two methods of geometrically stiffening a sphere were investigated and their W/B evaluated. A thin shelled sphere of beryllium stiffened with an isogrid of blade type stiffeners using Ultra High Modulus (UHM) carbon epoxy was predicted to give a W/B= 0.79. A geodesic sphere composed of a frame of cylindrical, UHM, carbon epoxy, pultruded rods with a thin external membrane was evaluated using Finite Element Analysis. A W/B=0.57 was calculated for the frame. The skin was predicted to add 0.37 to the W/B if Zylon was used to reinforce a Mylar membrane, which resulted in a predicted structure W/B=0.94. These structures were optimized using a non-linear programming optimization routine in MATLAB. A unique LTA vehicle concept composed of twin counter-rotating cylinders that made use of a virtual elliptical body to reduce drag and maintain structural integrity with a vacuum was also investigated and found to be infeasible

LEED Construction and Performance Standards Mission Accomplishment

CIVINS Capstone ReportCIVINSThe general focus of this project is on the current state of Leadership in Energy and Environmental Design (LEED) building requirements and mission statement accomplishment. The report includes the background, requirements, and performance of LEED certified buildings, and identifies key issues with the current system. In particular, the report explores the failure of buildings construct to LEED standards to achieve the advertised energy savings. Solutions and avenues to implementation of the solutions are then offered.http://archive.org/details/leedconstruction109454245

Using A Web-Based Supply Chain Management Simulation As An Experiential Learning Tool Across The Business Curriculum

A web based version of the common “Beer Distribution Game” that facilitates experiential learning was developed and tested for use across the business curriculum. While the fundamental elements of the original paper based game were preserved, the web-based on-line multiplayer version offers refinements to game play, administration and debriefing that allow more focus on the learning experience and open possible applications beyond the traditional one-time demonstration of the bullwhip effect. The web-based supply chain management simulation was tested and refined in Strategic Management courses and Integrated Business Curriculum courses at two widely separated universities. Students responded favorably to the on-line simulation and were very willing to reflect on what they learned about how they made decisions, how worked under conditions of uncertainty, how they treated information and how they worked in the supply chain environment. The simulation can be used to demonstrate systems thinking and various other concepts throughout the business school curriculum including courses in Operations Management, Strategy, Information Systems, and Marketing

Using a Web-Based Supply Chain Management Simulation as an Experiential Learning Tool Across The Business Curriculum

A web based version of the common Beer Distribution Game that facilitates experiential learning was developed and tested for use across the business curriculum. While the fundamental elements of the original paper based game were preserved, the web-based on-line multiplayer version offers refinements to game play, administration and debriefing that allow more focus on the learning experience and open possible applications beyond the traditional one-time demonstration of the bullwhip effect. The web-based supply chain management simulation was tested and refined in Strategic Management courses and Integrated Business Curriculum courses at two widely separated universities. Students responded favorably to the on-line simulation and were very willing to reflect on what they learned about how they made decisions, how worked under conditions of uncertainty, how they treated information and how they worked in the supply chain environment. The simulation can be used to demonstrate systems thinking and various other concepts throughout the business school curriculum including courses in Operations Management, Strategy, Information Systems, and Marketing

Fungal Endophytes Directly Increase the Competitive Effects of an Invasive Forb

Competitive outcomes among plants can vary in different abiotic and biotic conditions. Here we tested the effects of two phylotypes of Alternaria endophytes on the growth, competitive effects, and competitive responses of the exotic invasive forb Centaurea stoebe. Centaurea stoebe was a better competitor against North American grass species than grasses from its European home range in the absence of endophytes. However, one endophyte both increased the biomass of C. stoebe and reduced the competitive effect of North American grasses on C. stoebe. The competitive effects of C. stoebe on grass species native to North America were enhanced by both fungal endophytes, but not for native European grasses. We do not know the mechanism by which endophytes increased C. stoebe\u27s competitive ability, and particularly against biogeographically new neighbors, but one endophyte increased the competitive ability of C. stoebe without increasing its size, suggesting mechanisms unrelated to increased growth. We tested only a fraction of the different endophytic fungi that have been found in C. stoebe, only scratching the surface of understanding their indirect effects. However, our results are the first to demonstrate such effects of a fungal endophyte infecting an invasive forb, and one of the few to show that endophyte effects on competition do not have to be mediated through herbivory

A Process Framework For Implementing A Laptop Program

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Phosphonium Chloromercurate Room Temperature Ionic Liquids of Variable Composition

The system trihexyl(tetradecyl)phosphonium ([P66614]Cl)/mercury chloride (HgCl2) has been investigated by varying the stoichiometric ratios from 4:1 to 1:2 (25, 50, 75, 100, 150, and 200 mol % HgCl2). All investigated compositions turn out to give rise to ionic liquids (ILs) at room temperature. The prepared ionic liquids offer the possibility to study the structurally and compositionally versatile chloromercurates in a liquid state at low temperatures in the absence of solvents. [P66614]2[HgCl4] is a simple IL with one discrete type of anion, while [P66614]{HgCl3} (with {} indicating a polynuclear arrangement) is an ionic liquid with a variety of polyanionic species, with [Hg2Cl6]2– apparently being the predominant building block. [P66614]2[Hg3Cl8] and [P66614][Hg2Cl5] appear to be ILs at ambient conditions but lose HgCl2 when heated in a vacuum. For the liquids with the compositions 4:1 and 4:3, more than two discrete ions can be evidenced, namely, [P66614]+, [HgCl4]2–, and Cl– and [P66614]+, [HgCl4]2–, and the polynuclear {HgCl3}−, respectively. The different stoichiometric compositions were characterized by 199Hg NMR, Raman- and UV–vis spectroscopy, and cyclic voltammetry, among other techniques, and their densities and viscosities were determined. The [P66614]Cl/HgCl2 system shows similarities to the well-known chloroaluminate ILs (e.g., decrease in viscosity with increasing metal content after addition of more than 0.5 mol of HgCl2/mol [P66614]Cl, increasing density with increasing metal content, and the likely formation of polynuclear/polymeric/polyanionic species) but offer the advantage that they are air and water stable

Nitrogen Spatial Heterogeneity Influences Diversity Following Restoration in a Ponderosa Pine Forest, Montana

The resource heterogeneity hypothesis (RHH) is frequently cited in the ecological literature as an important mechanism for maintaining species diversity. The RHH has rarely been evaluated in the context of restoration ecology in which a commonly cited goal is to restore diversity. In this study we focused oil the spatial heterogeneity of total inorganic nitrogen (TIN) following restoration treatments in a ponderosa pine (Pinus ponderosa)/Douglas-fir (Pseudotsuga inenziesii) forest in western Montana, USA. Our objective was to evaluate relationships between understory species richness and TIN heterogeneity following mechanical thinning (thin-only), prescribed burning (burn-only), and mechanical thinning with prescribed burning (thin/burn) to discern the ecological and management implications of these restoration approaches. We employed a randomized block design, with three 9-ha replicates of each treatment and an untreated control. Within each treatment, we randomly established a 20 X 50 in (1000 m(2)) Plot in which we measured species richness across the entire plot and in 12 I-m 2 quadrats randomly placed within each larger plot. Additionally, we measured TIN from a grid consisting of 112 soil samples (0-5 cm) in each plot and computed standard deviations as a measure of heterogeneity. We found a correlation between the net increase in species richness and the TIN standard deviations one and two years following restoration treatments, supporting RHH. Using nonmetric multidimensional scaling ordination and chi-squared analysis, we found that high and low TIN quadrats contained different understory communities in 2003 and 2004, further supporting RHH. A comparison of restoration treatments demonstrated that thin/burn and burn-only treatments created higher N heterogeneity relative to the control. We also found that within prescribed burn treatments, TIN heterogeneity was positively correlated with fine-fuel consumption, a variable reflecting burn severity. These findings may lead to more informed restoration decisions that consider treatment effects on understory diversity in ponderosa pine/Douglas-fir ecosystems

Liquid systems Based on Tetra(n-butyl)phosphonium Acetate for the Non-dissolving Pretreatment of a Microcrystalline Cellulose (Avicel PH-101)

A non-dissolving pretreatment consisting in the direct contact of cellulose and the ionic liquid tetra(n-butyl)phosphonium acetate, or its fluid mixtures with other phosphonium ionic liquids or with molecular liquids such as ethanol or DMSO, causes a reduction in the crystallinity of the popular microcrystalline cellulose-type Avicel PH-101 under mild conditions. At the same time, the degree of polymerization and the thermal stability of the pretreated Avicel remain essentially unaltered with respect to the untreated Avicel. The diminution of the crystallinity has been related to the increase of the reactivity of the pretreated Avicel samples via analysis of the kinetics of their enzymatic hydrolysis. For selected samples, this improved reactivity has been confirmed through their effective carboxymethylation under a simplified and milder reaction procedureThis work was supported by Xunta de Galicia through project ED431B 2020/021, co-funded by the European Regional Development Fund. A.V.P. thanks the Spanish Ministry of Science and Innovation, the Spanish Research State Agency, and the European Social Fund for a “Ramón y Cajal” contract (RYC-2017-22849)S