11,862 research outputs found
Physical insight into the simultaneous optimization of structure and control
Recent trends in spacecraft design which yield larger structures with more stringent performance requirements place many flexible modes of the structure within the bandwidth of active controllers. The resulting complications to the spacecraft design make it highly desirable to understand the impact of structural changes on an optimally controlled structure. This work uses low structural models with optimal H(sub 2) and H(sub infinity) controllers to develop some basic insight into this problem. This insight concentrates on several basic approaches to improving controlled performance and how these approaches interact in determining the optimal designs. A numerical example is presented to demonstrate how this insight can be generalized to more complex problems
Dark soliton collisions in superfluid Fermi gases
In this work dark soliton collisions in a one-dimensional superfluid Fermi
gas are studied across the BEC-BCS crossover by means of a recently developed
finite-temperature effective field theory [S. N. Klimin, J. Tempere, G.
Lombardi, J. T. Devreese, Eur. Phys. J. B 88, 122 (2015)] . The evolution of
two counter-propagating solitons is simulated numerically based on the theory's
nonlinear equation of motion for the pair field. The resulting collisions are
observed to introduce a spatial shift into the trajectories of the solitons.
The magnitude of this shift is calculated and studied in different conditions
of temperature and spin-imbalance. When moving away from the BEC-regime, the
collisions are found to become inelastic, emitting the lost energy in the form
of small-amplitude density oscillations. This inelasticity is quantified and
its behavior analyzed and compared to the results of other works. The
dispersion relation of the density oscillations is calculated and is
demonstrated to show a good agreement with the spectrum of collective
excitations of the superfluid
Takayasu's arteritis in an adult female from Cameroon: diagnosis via Doppler echocardiography
No abstract available
The Pitfalls of Data Analysis
Greetings GPNSS members! I hope summer finds you well and enjoying the Great Plains in some way, whether that be starting a new field season, a long-overdue break from the office, or planning your next family vacation. For me, transitioning away from the demands of the Spring 2017 semester to data analyses and preparation of my own manuscripts are particularly exciting (well, as exciting as “office life” can be!). Over the past month, I have initiated a number of grandiose summer objectives, most of which include analysis or in some instances, re-analysis of data to address concerns raised during peer-review. Though the past month has been arduous and much time spend ascending the Program R learning curve, it has provided me with the subject of this editorial: the pitfalls of data analysis.
I have been Editor-in-Chief for nearly 9 years now, over which time I have processed hundreds of manuscripts and considered hundreds of additional reviews. Over the past decade, I have noticed an increasing emphasis on data analyses at the expense of a greater understanding of the biological system under study. I raise this issue not to de-emphasize the statistical advances within the various disciplines of natural resource management....in fact, quite the contrary! I appreciate and greatly admire the role we play in developing novel and rigorous analytical approaches. Nevertheless, I can’t help but wonder whether our role as resource managers has somehow been compromised. While I will likely never know if this is the case, it remains a question that continues to fester in my mind
Manuscript Content: Where Does it Belong?
One of the most common issues we address during content editing of papers for The Prairie Naturalist (journal) is the appropriate placement of content in the text body. Based on my experience with the editorial process, content placement also is one of the issues that authors are most resistant to suggestions or do not fully understand why we are so persistent about it (Thompson 2010). One of the primary objectives of scientific writing is to concisely and accurately disseminate information. Scientific papers are structured to help both the author and reader accomplish this objective. The material that belongs in each section of Journal is described in our manuscript submission guidelines and generally follows standard guidelines for scientific writing (Day and Gastel 1998, Council of Science Editors 2006, Thompson 2010). Content editing is intended to bring a manuscript into compliance with our current submission guidelines, though at this stage we sometimes have to deal with additional problems that were overlooked during the peer-review process. My intention here is to describe some common problems we seen in papers submitted to the journal relative to placing content in the appropriate sections, with a primary goal of helping authors prepare better papers for the journal
Preparing an Effective Poster Presentation
Greetings GPNSS members! By the time you read this editorial, many of have been experiencing the fury unleashed by ‘Old Man Winter’ and may find yourself counting the days until warmer spring temperatures return once again to the Great Plains. Until then, just a couple more months of bitter cold temperatures, strong winds, and blowing and drifting snow. But not to worry, winter also provides the cold weather enthusiasts among us a chance to enjoy a range of outdoor recreational opportunities, a chance to reflect on the previous year in review, exciting professional and personal opportunities ushered in by the New Year, and spending time with friends and family. For me, I write this editorial with just a week to go before the start of the 2019 annual conference of the Midwest Fish and Wildlife Conference. Though my preparation for professional conferences varies annually, a common denominator in any meeting I attend includes preparing poster presentations, the subject of this editorial.
As active GPNSS members, we have all looked at thousands of posters over our careers, among which those that were well prepared stood out from those that essentially presented a thesis or entire manuscript into the allotted space. The tendency to cram as much information as possible into a poster is complicated by the fact that poster displays often occur in large, noisy venues competing with others to be read; thus, they must have visual appeal to attract attention (Krausman and Cox 2018). Posters that appear to be prepared in haste with little consideration given to the presentation of information often are not well received (Krausman and Cox 2018). Developing a quality poster that effectively presents the primary results of your research is not a trivial matter. Thus, the objective of this editorial is to summarize the key components for quality posters that will attract attention and enable researchers to effectively display results of their work (Krausman and Cox 2018)
REPORTING RESULTS OF DATA ANALYSIS, PREPARING SCIENTIFIC MANUSCRIPTS, AND WEBSITE DEVELOPMENT EFFORTS
Preparation of scientific manuscripts and use and presentation of statistics have been topics of several commentaries from previous journal Editors-in-Chief, and have been submitted as invited papers, so I would like to share my perspective as the current Editor-in-Chief (Editor) of The Prairie Naturalist (Journal). Because there is not complete consensus among the experts about when hypothesis testing versus information theoretic methods, or Bayesian versus frequentist methods are suitable, previous Editors have avoided presenting their perspectives (Thompson 2010). I also will avoid presenting my perspective as Editor. I will, however, present my perspective on several of these approaches and then offer some guidelines for presenting results of some commonly used statistical methods in the Journal. Further, I will also highlight several recurring issues related to improper manuscript formatting that I continue to encounter and then provide several potential solutions to minimize future occurrences and in tum, expedite the peer-review process
Final Thoughts as Editor-in-Chief
Greetings GPNSS members! I write this editorial during a time of reflection as Editor-in-Chief of The Prairie Naturalist (TPN), and during unprecedented times as the global COVID-19 pandemic continues. In full disclosure, I do not have a particular topic for this editorial, other than to offer a few final thoughts as my time serving the Great Plains Natural Science Society and TPN
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