Spatio-temporal Learning with Arrays of Analog Nanosynapses

Emerging nanodevices such as resistive memories are being considered for hardware realizations of a variety of artificial neural networks (ANNs), including highly promising online variants of the learning approaches known as reservoir computing (RC) and the extreme learning machine (ELM). We propose an RC/ELM inspired learning system built with nanosynapses that performs both on-chip projection and regression operations. To address time-dynamic tasks, the hidden neurons of our system perform spatio-temporal integration and can be further enhanced with variable sampling or multiple activation windows. We detail the system and show its use in conjunction with a highly analog nanosynapse device on a standard task with intrinsic timing dynamics- the TI-46 battery of spoken digits. The system achieves nearly perfect (99%) accuracy at sufficient hidden layer size, which compares favorably with software results. In addition, the model is extended to a larger dataset, the MNIST database of handwritten digits. By translating the database into the time domain and using variable integration windows, up to 95% classification accuracy is achieved. In addition to an intrinsically low-power programming style, the proposed architecture learns very quickly and can easily be converted into a spiking system with negligible loss in performance- all features that confer significant energy efficiency.Comment: 6 pages, 3 figures. Presented at 2017 IEEE/ACM Symposium on Nanoscale architectures (NANOARCH

Neural mechanisms of reactivation-induced updating that enhance and distort memory

We remember a considerable number of personal experiences because we are frequently reminded of them, a process known as memory reactivation. Although memory reactivation helps to stabilize and update memories, reactivation may also introduce distortions if novel information becomes incorporated with memory. Here we used functional magnetic resonance imaging (fMRI) to investigate the neural mechanisms mediating reactivation-induced updating in memory for events experienced during a museum tour. During scanning, participants were shown target photographs to reactivate memories from the museum tour followed by a novel lure photograph from an alternate tour. Later, participants were presented with target and lure photographs and asked to determine whether the photographs showed a stop they visited during the tour. We used a subsequent memory analysis to examine neural recruitment during reactivation that was associated with later true and false memories. We predicted that the quality of reactivation, as determined by online ratings of subjective recollection, would increase subsequent true memories but also facilitate incorporation of the lure photograph, thereby increasing subsequent false memories. The fMRI results revealed that the quality of reactivation modulated subsequent true and false memories via recruitment of left posterior parahippocampal, bilateral retrosplenial, and bilateral posterior inferior parietal cortices. However, the timing of neural recruitment and the way in which memories were reactivated contributed to differences in whether memory reactivation led to distortions or not. These data reveal the neural mechanisms recruited during memory reactivation that modify how memories will be subsequently retrieved, supporting the flexible and dynamic aspects of memory

International and domestic regulator issues facing the Canadian MSAT system

International and domestic regulatory issues which affect the implementation of a mobile satellite system (MSAT) over North America are addressed. WARC-MOB-87, MSAT frequency co-ordination, frequency sharing and key Canadian domestic issues are discussed

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

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

Impact of Silo Storage Time and Specimen Fabrication Methods on Hot Mix Asphalt Mixtures

Performance of asphalt as a pavement material depends on a variety of factors such as mixture properties, the mix design process, and the way in which the materials are produced and placed. There are also different methods and practices in hot mix asphalt construction, such as the way in which specimens are fabricated for laboratory testing and the time that hot mix asphalt is stored at plants following production. There is currently a lack of understanding within the asphalt industry on the potential performance impacts of these variations. This thesis involves two projects that explored variations in the production and placement aspects of hot mix asphalt construction. One study that is included in this document aims to characterize the impact of silo storage time on asphalt mixtures. Many hot mix asphalt plants store material in heated silos before they are ready to be transported to construction sites. As the material is exposed to elevated temperatures, aging of the mixtures could increase susceptibility to cracking in the field. Through extensive binder and mixture testing, the results indicated that silo storage time has a significant impact on mixture performance, and RAP materials experienced a greater effect. Another study included in this thesis compares four different methods of producing specimens for laboratory testing: plant mixed, plant compacted; plant mixed, lab compacted; lab mixed, lab compacted; and small geometry specimens from field cores. Mixture testing showed that variations exist in stiffness characterization among the fabrication methods

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