MODEL PARAMETERS FOR THE DYNAMIC BEHAVIOR OF BURIED PIPES-PART 1

Author(s):  
Miroslav Georgiev Todorov

Pipeline systems are an integral part of modern human activity for much of the accompanying processes of lifestyle and industry. The design and construction of underground facilities solves one major problem-improving the quality of life by deploying the systems near the consumer, without intruding on the human environment. The necessity for more efficient behavior prognosis and evaluation as well as better design of buried pipelines during and after various actions (including geologic and seismic hazards) is directly related to the knowledge of their working mechanism, while aiming to prevent incidents which impact the human life. A number of additional parameters describing the conditions, behavior and effects of the pipeline system, going beyond the conventional Eurocode methods, is a requirement for the scope of this study. This study covers a comprehensive research system based on laboratory and in situ techniques, numerical analyses and the creation of interaction parameters of a buried pipe with soil massif in dynamic situations. Laboratory analyses were conducted in a laboratory triaxial state with cyclic shear strains. All parameters that were defined by constitution models-Mohr-Coulomb, Hardening soil model, Modified Cam-Clay based in a Plaxis software were traced. In the final phase of the publication (Part 2) the implementation and evaluation of the formulated parameters and results of the study are demonstrated.

Author(s):  
Pratik Chhapia ◽  
Harshad Patel

: Graphene based co-polymeric Nano-composites explored and trending in various applications as ascribing to its enhanced conductivity and controlled modification with wide specific surface areas. With the number of advantages of co-polymeric coating on Graphene or Graphene sheets and their derivatives, Graphene based co-polymeric Nano-composites fabricated by various techniques (deposition, ink jet, electro spinning, spin coating, in-situ techniques, etc.) and different conducting co-polymers show its exceptional chemical, mechanical, electrical and optical properties. Therefore, in the today’s world with greater quantities of various properties of co-polymer with Graphene based Nano-composites with enhanced stability, selectivity and sensitivity have been formed. In this review paper, we have particularly focused on recent advancing in fabrication of different technologies with the help of Graphene based co-polymeric Nano-composites and its various trending and future applications. Finally, on the personal standpoint; the key challenges of Graphene based co-polymeric Nano-composites are mentioned in hope to shed a light on their potential future prospects.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Björn Lindström ◽  
Martin Bellander ◽  
David T. Schultner ◽  
Allen Chang ◽  
Philippe N. Tobler ◽  
...  

AbstractSocial media has become a modern arena for human life, with billions of daily users worldwide. The intense popularity of social media is often attributed to a psychological need for social rewards (likes), portraying the online world as a Skinner Box for the modern human. Yet despite such portrayals, empirical evidence for social media engagement as reward-based behavior remains scant. Here, we apply a computational approach to directly test whether reward learning mechanisms contribute to social media behavior. We analyze over one million posts from over 4000 individuals on multiple social media platforms, using computational models based on reinforcement learning theory. Our results consistently show that human behavior on social media conforms qualitatively and quantitatively to the principles of reward learning. Specifically, social media users spaced their posts to maximize the average rate of accrued social rewards, in a manner subject to both the effort cost of posting and the opportunity cost of inaction. Results further reveal meaningful individual difference profiles in social reward learning on social media. Finally, an online experiment (n = 176), mimicking key aspects of social media, verifies that social rewards causally influence behavior as posited by our computational account. Together, these findings support a reward learning account of social media engagement and offer new insights into this emergent mode of modern human behavior.


Catalysts ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 143
Author(s):  
Melis S. Duyar ◽  
Alessandro Gallo ◽  
Samuel K. Regli ◽  
Jonathan L. Snider ◽  
Joseph A. Singh ◽  
...  

Molybdenum phosphide (MoP) catalyzes the hydrogenation of CO, CO2, and their mixtures to methanol, and it is investigated as a high-activity catalyst that overcomes deactivation issues (e.g., formate poisoning) faced by conventional transition metal catalysts. MoP as a new catalyst for hydrogenating CO2 to methanol is particularly appealing for the use of CO2 as chemical feedstock. Herein, we use a colloidal synthesis technique that connects the presence of MoP to the formation of methanol from CO2, regardless of the support being used. By conducting a systematic support study, we see that zirconia (ZrO2) has the striking ability to shift the selectivity towards methanol by increasing the rate of methanol conversion by two orders of magnitude compared to other supports, at a CO2 conversion of 1.4% and methanol selectivity of 55.4%. In situ X-ray Absorption Spectroscopy (XAS) and in situ X-ray Diffraction (XRD) indicate that under reaction conditions the catalyst is pure MoP in a partially crystalline phase. Results from Diffuse Reflectance Infrared Fourier Transform Spectroscopy coupled with Temperature Programmed Surface Reaction (DRIFTS-TPSR) point towards a highly reactive monodentate formate intermediate stabilized by the strong interaction of MoP and ZrO2. This study definitively shows that the presence of a MoP phase leads to methanol formation from CO2, regardless of support and that the formate intermediate on MoP governs methanol formation rate.


Molecules ◽  
2021 ◽  
Vol 26 (13) ◽  
pp. 3874
Author(s):  
Dominika Veselinyová ◽  
Jana Mašlanková ◽  
Katarina Kalinová ◽  
Helena Mičková ◽  
Mária Mareková ◽  
...  

We are experiencing rapid progress in all types of imaging techniques used in the detection of various numbers and types of mutation. In situ hybridization (ISH) is the primary technique for the discovery of mutation agents, which are presented in a variety of cells. The ability of DNA to complementary bind is one of the main principles in every method used in ISH. From the first use of in situ techniques, scientists paid attention to the improvement of the probe design and detection, to enhance the fluorescent signal intensity and inhibition of cross-hybrid presence. This article discusses the individual types and modifications, and is focused on explaining the principles and limitations of ISH division on different types of probes. The article describes a design of probes for individual types of in situ hybridization (ISH), as well as the gradual combination of several laboratory procedures to achieve the highest possible sensitivity and to prevent undesirable events accompanying hybridization. The article also informs about applications of the methodology, in practice and in research, to detect cell to cell communication and principles of gene silencing, process of oncogenesis, and many other unknown processes taking place in organisms at the DNA/RNA level.


Energies ◽  
2020 ◽  
Vol 14 (1) ◽  
pp. 72
Author(s):  
Sergiu Spataru ◽  
Peter Hacke ◽  
Dezso Sera

An in-situ method is proposed for monitoring and estimating the power degradation of mc-Si photovoltaic (PV) modules undergoing thermo-mechanical degradation tests that primarily manifest through cell cracking, such as mechanical load tests, thermal cycling and humidity freeze tests. The method is based on in-situ measurement of the module’s dark current-voltage (I-V) characteristic curve during the stress test, as well as initial and final module flash testing on a Sun simulator. The method uses superposition of the dark I-V curve with final flash test module short-circuit current to account for shunt and junction recombination losses, as well as series resistance estimation from the in-situ measured dark I-Vs and final flash test measurements. The method is developed based on mc-Si standard modules undergoing several stages of thermo-mechanical stress testing and degradation, for which we investigate the impact of the degradation on the modules light I-V curve parameters, and equivalent solar cell model parameters. Experimental validation of the method on the modules tested shows good agreement between the in-situ estimated power degradation and the flash test measured power loss of the modules, of up to 4.31 % error (RMSE), as the modules experience primarily junction defect recombination and increased series resistance losses. However, the application of the method will be limited for modules experiencing extensive photo-current degradation or delamination, which are not well reflected in the dark I-V characteristic of the PV module.


2021 ◽  
pp. 1-8
Author(s):  
Carina Wyborn ◽  
Elena Louder ◽  
Mike Harfoot ◽  
Samantha Hill

Summary Future global environmental change will have a significant impact on biodiversity through the intersecting forces of climate change, urbanization, human population growth, overexploitation, and pollution. This presents a fundamental challenge to conservation approaches, which seek to conserve past or current assemblages of species or ecosystems in situ. This review canvases diverse approaches to biodiversity futures, including social science scholarship on the Anthropocene and futures thinking alongside models and scenarios from the biophysical science community. It argues that charting biodiversity futures requires processes that must include broad sections of academia and the conservation community to ask what desirable futures look like, and for whom. These efforts confront political and philosophical questions about levels of acceptable loss, and how trade-offs can be made in ways that address the injustices in the distribution of costs and benefits across and within human and non-human life forms. As such, this review proposes that charting biodiversity futures is inherently normative and political. Drawing on diverse scholarship united under a banner of ‘futures thinking’ this review presents an array of methods, approaches and concepts that provide a foundation from which to consider research and decision-making that enables action in the context of contested and uncertain biodiversity futures.


2021 ◽  
Vol 13 (10) ◽  
pp. 1865
Author(s):  
Gabriel Calassou ◽  
Pierre-Yves Foucher ◽  
Jean-François Léon

Stack emissions from the industrial sector are a subject of concern for air quality. However, the characterization of the stack emission plume properties from in situ observations remains a challenging task. This paper focuses on the characterization of the aerosol properties of a steel plant stack plume through the use of hyperspectral (HS) airborne remote sensing imagery. We propose a new method, based on the combination of HS airborne acquisition and surface reflectance imagery derived from the Sentinel-2 Multi-Spectral Instrument (MSI). The proposed method detects the plume footprint and estimates the surface reflectance under the plume, the aerosol optical thickness (AOT), and the modal radius of the plume. Hyperspectral surface reflectances are estimated using the coupled non-negative matrix factorization (CNMF) method combining HS and MSI data. The CNMF reduces the error associated with estimating the surface reflectance below the plume, particularly for heterogeneous classes. The AOT and modal radius are retrieved using an optimal estimation method (OEM), based on the forward model and allowing for uncertainties in the observations and in the model parameters. The a priori state vector is provided by a sequential method using the root mean square error (RMSE) metric, which outperforms the previously used cluster tuned matched filter (CTMF). The OEM degrees of freedom are then analysed, in order to refine the mask plume and to enhance the quality of the retrieval. The retrieved mean radii of aerosol particles in the plume is 0.125 μμm, with an uncertainty of 0.05 μμm. These results are close to the ultra-fine mode (modal radius around 0.1 μμm) observed from in situ measurements within metallurgical plant plumes from previous studies. The retrieved AOT values vary between 0.07 (near the source point) and 0.01, with uncertainties of 0.005 for the darkest surfaces and above 0.010 for the brightest surfaces.


2006 ◽  
Vol 29 (3) ◽  
pp. 259-280 ◽  
Author(s):  
John L. Locke ◽  
Barry Bogin

It has long been claimed that Homo sapiens is the only species that has language, but only recently has it been recognized that humans also have an unusual pattern of growth and development. Social mammals have two stages of pre-adult development: infancy and juvenility. Humans have two additional prolonged and pronounced life history stages: childhood, an interval of four years extending between infancy and the juvenile period that follows, and adolescence, a stage of about eight years that stretches from juvenility to adulthood. We begin by reviewing the primary biological and linguistic changes occurring in each of the four pre-adult ontogenetic stages in human life history. Then we attempt to trace the evolution of childhood and juvenility in our hominin ancestors. We propose that several different forms of selection applied in infancy and childhood; and that, in adolescence, elaborated vocal behaviors played a role in courtship and intrasexual competition, enhancing fitness and ultimately integrating performative and pragmatic skills with linguistic knowledge in a broad faculty of language. A theoretical consequence of our proposal is that fossil evidence of the uniquely human stages may be used, with other findings, to date the emergence of language. If important aspects of language cannot appear until sexual maturity, as we propose, then a second consequence is that the development of language requires the whole of modern human ontogeny. Our life history model thus offers new ways of investigating, and thinking about, the evolution, development, and ultimately the nature of human language.


2005 ◽  
Vol 576 (1) ◽  
pp. 139-145 ◽  
Author(s):  
H.J. Salavagione ◽  
J. Arias-Pardilla ◽  
J.M. Pérez ◽  
J.L. Vázquez ◽  
E. Morallón ◽  
...  

2013 ◽  
Vol 1491 ◽  
Author(s):  
Jayme Keist ◽  
Christine Orme ◽  
Frances Ross ◽  
Dan Steingart ◽  
Paul Wright ◽  
...  

ABSTRACTThis investigation describes preliminary results of in-situ analysis of zinc deposition within an ionic liquid electrolyte utilizing electrochemical atomic force microscopy (EC AFM). From the AFM analysis, the morphology of the zinc deposition was analyzed by quantifying the surface roughness using height-height correlation functions. These results will be used to analyze the scattering data obtained from zinc deposition analysis utilizing an electrochemical ultra-small angle x-ray scattering (EC USAXS). The goal of this research is to link the early nucleation and growth behavior to the formation of detrimental morphologies.


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