42 research outputs found

    Using Your Kodak

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    When we pack up the car for that touring trip this summer, there will be one thing that won\u27t be packed away as far out of sight and reach as possible. That is the camera, and it will be where we can get it at a moment\u27s notice. It may may be an ordinary box camera costing a dollar or it may be a high-priced folding kodak with all the newest attachments and a lens worth a month\u27s salary. But the kind of a camera isn\u27t the main thing. Any kind, no matter what. the price, will give us a record of our Journey and preserve reminders of the people we \u27meet or see, the cities we visit, and the wonderful things that nature has m store for every traveler. But maybe a few hints may be useful in helping you to get the best pictures possible

    The Iowa Homemaker vol.4, no.2

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    Table of Contents To the High School Girls of Iowa by Anna E. Richardson, page 3 For the College Room by Barbara Mills Dewell, page 4 The Junior-Senior Banquet by Viola Jammer and Pauline Peacock, page 4 Picnic Preparations by Louise Evans Doole, page 5 Finding Yourself by H. M. Hamlin, page 6 Stories of the Sand by Katherine Holden, page 7 Appropriate Pictures for the Home by Amanda Jacobson, page 8 The Individual Scarf by Rhea Fern Schultz, page 9 Using Your Kodak by H. P. Doole, page 10 Something Plus by Laura E. Bublitz, page 11 The Ideal Homemaker by Rosalie Larson, page 12 University Life in France by Mercie Carley, page 12 Homemaker as Citizen by Jeanette Beyer, page 13 Who’s There and Where by Dryden Quist, page 14 Editorial, page 15 The Eternal Question, page 1

    Exact travelling wave solutions of a beam equation

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    In this paper we make a full analysis of the symmetry reductions of a beam equation by using the classical Lie method of infinitesimals and the nonclassical method. We consider travelling wave reductions depending on the form of an arbitrary function. We have found several new classes of solutions that have not been considered before: solutions expressed in terms of Jacobi elliptic functions, Wadati solitons and compactons. Several classes of coherent structures are displayed by some of the solutions: kinks, solitons, two humps compactons.17 página

    A microscopic model for thin film spreading

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    A microscopic, driven lattice gas model is proposed for the dynamics and spatio-temporal fluctuations of the precursor film observed in spreading experiments. Matter is transported both by holes and particles, and the distribution of each can be described by driven diffusion with a moving boundary. This picture leads to a stochastic partial differential equation for the shape of the boundary, which agrees with the simulations of the lattice gas. Preliminary results for flow in a thermal gradient are discussed.Comment: 4 pages, 3 figures. Submitte

    The Role of Motor Learning in Spatial Adaptation near a Tool

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    Some visual-tactile (bimodal) cells have visual receptive fields (vRFs) that overlap and extend moderately beyond the skin of the hand. Neurophysiological evidence suggests, however, that a vRF will grow to encompass a hand-held tool following active tool use but not after passive holding. Why does active tool use, and not passive holding, lead to spatial adaptation near a tool? We asked whether spatial adaptation could be the result of motor or visual experience with the tool, and we distinguished between these alternatives by isolating motor from visual experience with the tool. Participants learned to use a novel, weighted tool. The active training group received both motor and visual experience with the tool, the passive training group received visual experience with the tool, but no motor experience, and finally, a no-training control group received neither visual nor motor experience using the tool. After training, we used a cueing paradigm to measure how quickly participants detected targets, varying whether the tool was placed near or far from the target display. Only the active training group detected targets more quickly when the tool was placed near, rather than far, from the target display. This effect of tool location was not present for either the passive-training or control groups. These results suggest that motor learning influences how visual space around the tool is represented

    An ecological future for weed science to sustain crop production and the environment. A review

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    Sustainable strategies for managing weeds are critical to meeting agriculture's potential to feed the world's population while conserving the ecosystems and biodiversity on which we depend. The dominant paradigm of weed management in developed countries is currently founded on the two principal tools of herbicides and tillage to remove weeds. However, evidence of negative environmental impacts from both tools is growing, and herbicide resistance is increasingly prevalent. These challenges emerge from a lack of attention to how weeds interact with and are regulated by the agroecosystem as a whole. Novel technological tools proposed for weed control, such as new herbicides, gene editing, and seed destructors, do not address these systemic challenges and thus are unlikely to provide truly sustainable solutions. Combining multiple tools and techniques in an Integrated Weed Management strategy is a step forward, but many integrated strategies still remain overly reliant on too few tools. In contrast, advances in weed ecology are revealing a wealth of options to manage weedsat the agroecosystem levelthat, rather than aiming to eradicate weeds, act to regulate populations to limit their negative impacts while conserving diversity. Here, we review the current state of knowledge in weed ecology and identify how this can be translated into practical weed management. The major points are the following: (1) the diversity and type of crops, management actions and limiting resources can be manipulated to limit weed competitiveness while promoting weed diversity; (2) in contrast to technological tools, ecological approaches to weed management tend to be synergistic with other agroecosystem functions; and (3) there are many existing practices compatible with this approach that could be integrated into current systems, alongside new options to explore. Overall, this review demonstrates that integrating systems-level ecological thinking into agronomic decision-making offers the best route to achieving sustainable weed management

    Review of mathematical programming applications in water resource management under uncertainty

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    A Certain Multiple-Parameter Expansion

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    C. C. Camp has shown the convergence of the expansion of an arbitrary function in terms of the solutions of the systems of equations X1’ (λa1 - Σi=2nμi)X1 = 0, X1’ (λai + μi)Xi = 0, (j = 2, 3, …, n), where the ai’s are functions of x, with the boundary conditions Xi(-π) = Xi(π), (j = 1, 2, …, n). In this paper it is intended to use a differential system in which the n parameters appear in each equation with a function ajk(xj) multiplying each. The boundary conditions will also be more general

    A certain multiple-parameter expansion

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