117,024 research outputs found
An M-QAM Signal Modulation Recognition Algorithm in AWGN Channel
Computing the distinct features from input data, before the classification,
is a part of complexity to the methods of Automatic Modulation Classification
(AMC) which deals with modulation classification was a pattern recognition
problem. Although the algorithms that focus on MultiLevel Quadrature Amplitude
Modulation (M-QAM) which underneath different channel scenarios was well
detailed. A search of the literature revealed indicates that few studies were
done on the classification of high order M-QAM modulation schemes like128-QAM,
256-QAM, 512-QAM and1024-QAM. This work is focusing on the investigation of the
powerful capability of the natural logarithmic properties and the possibility
of extracting Higher-Order Cumulant's (HOC) features from input data received
raw. The HOC signals were extracted under Additive White Gaussian Noise (AWGN)
channel with four effective parameters which were defined to distinguished the
types of modulation from the set; 4-QAM~1024-QAM. This approach makes the
recognizer more intelligent and improves the success rate of classification.
From simulation results, which was achieved under statistical models for noisy
channels, manifest that recognized algorithm executes was recognizing in M-QAM,
furthermore, most results were promising and showed that the logarithmic
classifier works well over both AWGN and different fading channels, as well as
it can achieve a reliable recognition rate even at a lower signal-to-noise
ratio (less than zero), it can be considered as an Integrated Automatic
Modulation Classification (AMC) system in order to identify high order of M-QAM
signals that applied a unique logarithmic classifier, to represents higher
versatility, hence it has a superior performance via all previous works in
automatic modulation identification systemComment: 18 page
SPH-EXA: Enhancing the Scalability of SPH codes Via an Exascale-Ready SPH Mini-App
Numerical simulations of fluids in astrophysics and computational fluid
dynamics (CFD) are among the most computationally-demanding calculations, in
terms of sustained floating-point operations per second, or FLOP/s. It is
expected that these numerical simulations will significantly benefit from the
future Exascale computing infrastructures, that will perform 10^18 FLOP/s. The
performance of the SPH codes is, in general, adversely impacted by several
factors, such as multiple time-stepping, long-range interactions, and/or
boundary conditions. In this work an extensive study of three SPH
implementations SPHYNX, ChaNGa, and XXX is performed, to gain insights and to
expose any limitations and characteristics of the codes. These codes are the
starting point of an interdisciplinary co-design project, SPH-EXA, for the
development of an Exascale-ready SPH mini-app. We implemented a rotating square
patch as a joint test simulation for the three SPH codes and analyzed their
performance on a modern HPC system, Piz Daint. The performance profiling and
scalability analysis conducted on the three parent codes allowed to expose
their performance issues, such as load imbalance, both in MPI and OpenMP.
Two-level load balancing has been successfully applied to SPHYNX to overcome
its load imbalance. The performance analysis shapes and drives the design of
the SPH-EXA mini-app towards the use of efficient parallelization methods,
fault-tolerance mechanisms, and load balancing approaches.Comment: arXiv admin note: substantial text overlap with arXiv:1809.0801
Lisp, Jazz, Aikido -- Three Expressions of a Single Essence
The relation between Science (what we can explain) and Art (what we can't)
has long been acknowledged and while every science contains an artistic part,
every art form also needs a bit of science. Among all scientific disciplines,
programming holds a special place for two reasons. First, the artistic part is
not only undeniable but also essential. Second, and much like in a purely
artistic discipline, the act of programming is driven partly by the notion of
aesthetics: the pleasure we have in creating beautiful things. Even though the
importance of aesthetics in the act of programming is now unquestioned, more
could still be written on the subject. The field called "psychology of
programming" focuses on the cognitive aspects of the activity, with the goal of
improving the productivity of programmers. While many scientists have
emphasized their concern for aesthetics and the impact it has on their
activity, few computer scientists have actually written about their thought
process while programming. What makes us like or dislike such and such language
or paradigm? Why do we shape our programs the way we do? By answering these
questions from the angle of aesthetics, we may be able to shed some new light
on the art of programming. Starting from the assumption that aesthetics is an
inherently transversal dimension, it should be possible for every programmer to
find the same aesthetic driving force in every creative activity they
undertake, not just programming, and in doing so, get deeper insight on why and
how they do things the way they do. On the other hand, because our aesthetic
sensitivities are so personal, all we can really do is relate our own
experiences and share it with others, in the hope that it will inspire them to
do the same. My personal life has been revolving around three major creative
activities, of equal importance: programming in Lisp, playing Jazz music, and
practicing Aikido. But why so many of them, why so different ones, and why
these specifically? By introspecting my personal aesthetic sensitivities, I
eventually realized that my tastes in the scientific, artistic, and physical
domains are all motivated by the same driving forces, hence unifying Lisp,
Jazz, and Aikido as three expressions of a single essence, not so different
after all. Lisp, Jazz, and Aikido are governed by a limited set of rules which
remain simple and unobtrusive. Conforming to them is a pleasure. Because Lisp,
Jazz, and Aikido are inherently introspective disciplines, they also invite you
to transgress the rules in order to find your own. Breaking the rules is fun.
Finally, if Lisp, Jazz, and Aikido unify so many paradigms, styles, or
techniques, it is not by mere accumulation but because they live at the
meta-level and let you reinvent them. Working at the meta-level is an
enlightening experience. Understand your aesthetic sensitivities and you may
gain considerable insight on your own psychology of programming. Mine is
perhaps common to most lispers. Perhaps also common to other programming
communities, but that, is for the reader to decide..
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BioScript: programming safe chemistry on laboratories-on-a-chip
This paper introduces BioScript, a domain-specific language (DSL) for programmable biochemistry which executes on emerging microfluidic platforms. The goal of this research is to provide a simple, intuitive, and type-safe DSL that is accessible to life science practitioners. The novel feature of the language is its syntax, which aims to optimize human readability; the technical contributions of the paper include the BioScript type system and relevant portions of its compiler. The type system ensures that certain types of errors, specific to biochemistry, do not occur, including the interaction of chemicals that may be unsafe. The compiler includes novel optimizations that place biochemical operations to execute concurrently on a spatial 2D array platform on the granularity of a control flow graph, as opposed to individual basic blocks. Results are obtained using both a cycle-accurate microfluidic simulator and a software interface to a real-world platform
Numerical simulation of electric signal in the cyber-physical immunosensor system on rectangular lattice in R package
Проведено чисельне моделювання електричного сигналу з перетворювача в кіберфізичній імуносенсорній системі на прямокутній решітці з використанням диференціальних рівнянь із запізненням за допомогою пакета R. Описано функціональні можливості пакета R як середовища програмування для статистичного аналізу даних, наведено корисні сайти, списки посилань і документація пакета R. У вигляді таблиці представлено назви параметрів моделі імуносенсора на прямокутній решітці з використанням диференціальних рівнянь із запізненням та їх числові значення в пакеті R. Реалізовано комп’ютерну програму «Чисельний аналіз електричного сигналу з перетворювача, який характеризує кількість флуоресціюючих пікселів в імуносенсорі на прямокутній решітці з використанням диференціальних рівнянь із запізненням». Розроблена комп’ютерна програма дає змогу провести дослідження стійкості імуносенсорних систем, які широко використовуються для отримання діагностичної інформації з метою оцінювання критичних станів при серцево-судинних захворюваннях, величини інсуліну при вимірюванні величини глюкози в крові та виявлення кількісних показників у деяких фармацевтичних сполуках. Наведено фрагмент лістингу комп’ютерної програми в пакеті R для отримання електричного сигналу з перетворювача, який характеризує кількість флуоресціюючих пікселів у кіберфізичній імуносенсорній системі на прямокутній решітці з використанням диференціальних рівнянь із запізненням. Проведено чисельне моделювання для електричного сигналу з перетворювача в імуносенсорі на прямокутній решітці з використанням диференціальних рівнянь із запізненням. Проаналізовано зміни отриманого електричного сигналу, які відповідають кількості флуоресціюючих пікселів у кіберфізичній імуносенсорній системі. Обгрунтовано використання пакета R як вільнопоширюваного програмного забезпечення з графічною візуалізацією результатів аналізу.The numerical simulation of electric signal from the converter in the cyber-physical immunosensor system on rectangular lattice using differential equations with delay by means of R package is carried out in this paper. The functional features of R package as a programming environment for statistical data analysis are described, useful sites, references lists and documentation of R package are given. The names of parameters of the immunosensor model on rectangular lattice using the differential equations with delay and their numerical values in the package R are presented in the form of the table. The computer program «Numerical analysis of the electrical signal from the converter that characterizes the number of fluorescing pixels in the immunosensor on rectangular lattice using delayed differential equations» is implemented. The developed computer program makes it possible to carry out the investigation of the stability of immunosensory systems, which are widely used to obtain diagnostic information in order to evaluate critical states of cardiovascular disease, insulin values while measuring blood glucose values and identify quantitative indicators in some рharmaceutics compounds. The fragment of computer program listing in R package for obtaining the electrical signal from converter characterizing the number of fluorescent pixels in cyber-physical immunosensor system on rectangular lattice using delayed differential equations is presented. Numerical simulation for the electric signal from the converter in the immunosensor on rectangular lattice using the delayed differential equations is carried out. The changes of the received electrical signal corresponding to the number of fluorescent pixels in the cyber-physical immunosensory system are analyzed. The use of R package as a freely distributed software with graphical visualization of the analysis results is substantiated
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Epigenetic Down-Regulation of Sirt 1 via DNA Methylation and Oxidative Stress Signaling Contributes to the Gestational Diabetes Mellitus-Induced Fetal Programming of Heart Ischemia-Sensitive Phenotype in Late Life.
Rationale: The incidence of gestational diabetes mellitus (GDM) is increasing worldwide. However, whether and how GDM exposure induces fetal programming of adult cardiac dysfunctional phenotype, especially the underlying epigenetic molecular mechanisms and theranostics remain unclear. To address this problem, we developed a late GDM rat model. Methods: Pregnant rats were made diabetic on day 12 of gestation by streptozotocin (STZ). Experiments were conducted in 6 weeks old offspring. Results: There were significant increases in ischemia-induced cardiac infarction and gender-dependent left ventricular (LV) dysfunction in male offspring in GDM group as compared to controls. Exposure to GDM enhanced ROS level and caused a global DNA methylation in offspring cardiomyocytes. GDM attenuated cardiac Sirt 1 protein and p-Akt/Akt levels, but enhanced autophagy-related proteins expression (Atg 5 and LC3 II/LC3 I) as compared to controls. Ex-vivo treatment of DNA methylation inhibitor, 5-Aza directly inhibited Dnmt3A and enhanced Sirt 1 protein expression in fetal hearts. Furthermore, treatment with antioxidant, N-acetyl-cysteine (NAC) in offspring reversed GDM-mediated DNA hypermethylation, Sirt1 repression and autophagy-related gene protein overexpression in the hearts, and rescued GDM-induced deterioration in heart ischemic injury and LV dysfunction. Conclusion: Our data indicated that exposure to GDM induced offspring cardiac oxidative stress and DNA hypermethylation, resulting in an epigenetic down-regulation of Sirt1 gene and aberrant development of heart ischemia-sensitive phenotype, which suggests that Sirt 1-mediated signaling is the potential therapeutic target for the heart ischemic disease in offspring
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