12 research outputs found
Neocortical catastrophic interference in healthy and amnesic adults: A paradoxical matter of time
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Some Families of Jensen-like Inequalities with Application to Information Theory
No full textIt is well known that the traditional Jensen inequality is proved by lower bounding the given convex function, f(x), by the tangential affine function that passes through the point (E{X},f(E{X})), where E{X} is the expectation of the random variable X. While this tangential affine function yields the tightest lower bound among all lower bounds induced by affine functions that are tangential to f, it turns out that when the function f is just part of a more complicated expression whose expectation is to be bounded, the tightest lower bound might belong to a tangential affine function that passes through a point different than (E{X},f(E{X})). In this paper, we take advantage of this observation by optimizing the point of tangency with regard to the specific given expression in a variety of cases and thereby derive several families of inequalities, henceforth referred to as “Jensen-like” inequalities, which are new to the best knowledge of the author. The degree of tightness and the potential usefulness of these inequalities is demonstrated in several application examples related to information theory
Conditional Complexity of Compression for Authorship Attribution
No full textWe introduce new stylometry tools based on the sliced conditional compression complexity of literary texts which are inspired by the nearly optimal application of the incomputable Kolmogorov conditional complexity (and presumably approximates it). Whereas other stylometry tools can occasionally be very close for different authors, our statistic is apparently strictly minimal for the true author, if the query and training texts are sufficiently large, compressor is sufficiently good and sampling bias is avoided (as in the poll samplings). We tune it and test its performance on attributing the Federalist papers (Madison vs. Hamilton). Our results confirm the previous attribution of Federalist papers by Mosteller and Wallace (1964) to Madison using the Naive Bayes classifier and the same attribution based on alternative classifiers such as SVM, and the second order Markov model of language. Then we apply our method for studying the attribution of the early poems from the Shakespeare Canon and the continuation of Marlowe’s poem ‘Hero and Leander’ ascribed to G. Chapman.compression complexity, authorship attribution.
An example of mathematical authorship attribution
No full textIn this paper we discuss a novel mathematical approach to authorship attribution which we implemented recently to face a concrete problem of author recognition. The fundamental ideas for our methods came from statistical mechanics and information theory. We combine two approaches. Both of them use similarity measures between couples of texts as indicators of stylistic closeness: the first one is based on the comparison of frequencies of fixed length substrings (n-grams) throughout the texts; the second one relies on a suitable use of compression algorithms as relative entropy approximators, in the spirit of the so-called Ziv-Merhav theorem. The two methods were separately developed and then combined, together with a suitable and theoretically founded ranking analysis, to produce an original authorship attribution procedure that yielded very successful results on the specific problem to which it was applied. This ranking analysis could be of interest also in other application fields
Machine Learning Techniques and the Existence of Variant Processes in Humans Declarative Memory
No full textThe Existence of Two Variant Processes in Human Declarative Memory: Evidence Using Machine Learning Classification Techniques in Retrieval Tasks
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Development of a reproducible and optimized protocol for freeform reversible embedding of suspended hydrogels
No full textOrgan failure occurs when a bodily system is unable to perform tasks that are necessary for survival, and they can be caused by any significant change to internal body conditions, ranging from chronic diseases to sudden injuries. Long term or irreversible organ failure is most effectively treated with the transplantation of a donated replacement organ as a substitute for the diseased system. The number of patients who require an organ transplant significantly outnumbers available replacements both in the US and worldwide, resulting in many patients dying while on transplant waiting lists. Because organ donations cannot keep up with organ failure prevalence, there exists a need for other avenues of obtaining functional replacements.
3D biofabrication technologies have grown significantly in recent years and show promise as powerful tools in the creation of customizable and biocompatible organ components and even entire organ structures. However, materials that provide the ideal bioactivity necessary for development of fully functional artificial organs are rarely usable in conventional 3D biofabrication methods due to their incompatibility with high temperatures and inability to maintain their configuration after their extrusion. Recent advancements in a 3D biofabrication technology known as freeform reversible embedding of suspended hydrogels (FRESH), which uses a gelatin microbead support bath to maintain structural integrity, may provide an avenue for using these materials in more versatile ways, but published literature pertaining to this technique is lacking in detail in both material and process. Published material pertaining to FRESH printing also lacks description of how variations in processing steps and material properties affect experimental results, only reporting the specific steps that led to significant results. These information gaps make it difficult for new researchers to recreate and build upon what has already been developed. In order for FRESH printing to progress to the point where it is usable in clinics for creating artificial transplant organs, it is necessary for a full understanding of the technology and its protocols to be accessible.
In this thesis, the beginnings of a detailed FRESH printing protocol are established. It is determined that low blend time in the creation of the gelatin slurry used in FRESH results in a nonuniform support bath that is unusable in printing. This study also produced a protocol for creating a collagen-based bioink using customizable materials and found that existing protocols for FRESH printing using collagen inks may not be broadly effective. Lab closures cause by the COVID-19 pandemic prevented further analysis and protocol building, but a foundation has been laid for an accessible understanding of FRESH printing technologies.M.S.Includes bibliographical reference
