scholarly journals A Study on the Effect of O2 Diffusion on the Retention Time of Inert Agents

2020 ◽  
Vol 10 (19) ◽  
pp. 6694
Author(s):  
GoonHo Kim ◽  
Ju-Hong Cha ◽  
Jee-Hun Jeong ◽  
Ho-Jun Lee
Keyword(s):  
Theoretical Model ◽  
Retention Time ◽  
Hold Time ◽  
Theoretical Models ◽  
Accurate Model ◽  
Fire Extinguishing ◽  
A Value ◽  
O2 Diffusion ◽  
In Fire ◽  
And Diffusion

Gaseous agents are widely used in fire extinguishing systems (FESs) when water extinguishing agents are unavailable. The extinguishing ability of the FES-gaseous agent is determined by the retention time (hold time) at which its concentration is maintained. In particular, the retention time of the inert agent is determined by the O2 inflow from the outside. However, current theoretical models for inert agents do not provide an accurate model for the diffusion of incoming O2. Specifically, because the theoretical equations do not include O2 diffusion or include too large a value, there is a large difference between the measured and theoretical retention times. Therefore, in this study, accurate O2 diffusion was verified through experimental and numerical analyses using three types of deactivators and reflected in the existing theoretical model. O2 diffusion was analyzed through the interface slope α and diffusion velocity vd. As a result, this proposed method can predict the retention time more accurately than existing theoretical models.

The Social Neuroscience of Cooperation

2018 ◽  
Author(s):  
Jay Joseph Van Bavel
Keyword(s):  
Theoretical Models ◽  
Brain Regions ◽  
Review Literature ◽  
Social Neuroscience ◽  
Future Research ◽  
A Value ◽  
Group Cooperation ◽  
Neural Processes ◽  
The Social ◽  
Cooperative Decision Making

We review literature from several fields to describe common experimental tasks used to measure human cooperation as well as the theoretical models that have been used to characterize cooperative decision-making, as well as brain regions implicated in cooperation. Building on work in neuroeconomics, we suggest a value-based account may provide the most powerful understanding the psychology and neuroscience of group cooperation. We also review the role of individual differences and social context in shaping the mental processes that underlie cooperation and consider gaps in the literature and potential directions for future research on the social neuroscience of cooperation. We suggest that this multi-level approach provides a more comprehensive understanding of the mental and neural processes that underlie the decision to cooperate with others.

Investigation on penetration model of shaped charge jet in water

2016 ◽  
Vol 30 (02) ◽  
pp. 1550268 ◽  
Author(s):  
Jinwei Shi ◽  
Xingbai Luo ◽  
Jinming Li ◽  
Jianwei Jiang
Keyword(s):  
Numerical Simulation ◽  
Theoretical Model ◽  
Model Simulation ◽  
Theoretical Models ◽  
Theoretical Research ◽  
Water Medium ◽  
Simulation Results ◽  
Jet Penetration ◽  
The Impact ◽  
Penetration Velocity

To analyze the process of jet penetration in water medium quantitatively, the properties of jet penetration spaced target with water interlayer were studied through test and numerical simulation. Two theoretical models of jet penetration in water were proposed. The theoretical model 1 was established considering the impact of the shock wave, combined with the shock equation Rankine–Hugoniot and the virtual origin calculation method. The theoretical model 2 was obtained by fitting theoretical analysis and numerical simulation results. The effectiveness and universality of the two theoretical models were compared through the numerical simulation results. Both the models can reflect the relationship between the penetration velocity and the penetration distance in water well, and both the deviation and stability of theoretical model 1 are better than 2, the lower penetration velocity, and the larger deviation of the theoretical model 2. Therefore, the theoretical model 1 can reflect the properties of jet penetration in water effectively, and provide the reference of model simulation and theoretical research.

An Analysis of Conventional and Self-Aligned four Terminal Resistor Structures for The Determination of The Contact Resistivity from End Resistance Measurements

1986 ◽  
Vol 71 ◽  
Author(s):  
I. Suni ◽  
M. Finetti ◽  
K. Grahn
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Computer Model ◽  
Contact Resistivity ◽  
Experimental Results ◽  
The Finite Element Method ◽  
Model Based ◽  
A Value ◽  
And Diffusion

AbstractA computer model based on the finite element method has been applied to evaluate the effect of the parasitic area between contact and diffusion edges on end resistance measurements in four terminal Kelvin resistor structures. The model is then applied to Al/Ti/n+ Si contacts and a value of contact resistivity of Qc = 1.8×10−7.Ωcm2 is derived. For comparison, the use of a self-aligned structure to avoid parasitic effects is presented and the first experimental results obtained on Al/Ti/n+Si and Al/CoSi2/n+Si contacts are shown and discussed.

scholarly journals A relação entre ciência e tecnologia a partir de três modelos teóricos distintos

DoisPontos ◽  
2015 ◽  
Vol 12 (1) ◽  
Author(s):  
Gilmar Evandro Szczepanik
Keyword(s):  
Theoretical Model ◽  
Science And Technology ◽  
Theoretical Models ◽  
The Third

resumo: Este artigo tem por objetivo explorar as possíveis relações estabelecidas entre ciência e a tecnologia a partir de três modelos teóricos distintos. O primeiro modelo teórico é chamado de hierárquico e pressupõe uma relação de subordinação entre ciência e a tecnologia. O segundo modelo é denominado de não hierárquico e sustenta que ciência e a tecnologia se encontram fundidas de tal modo que não faz mais sentido tentar entendê-las separadamente. Por fim, o terceiro modelo teórico designado de emancipatório explora alguns elementos que permitem compreender a ciência e a tecnologia ainda como atividades distintas, embora possam trabalhar conjuntamente algumas vezes.Abstract:  This paper aims to  understand the possible  relations between science and technology from three different theoretical models. The first theoretical model is called hierarchical and implies a subordinate relationship between science and technology. The second model  is  called non-hierarchical  and argues  that  science  and technology are fused so that it makes more sense to try to understand them separately. Finally, the third theoretical model is called emancipatory  and explores some elements that allow us to understand science and technology as separate activities, although they may sometimes work together. 

scholarly journals Change in the Complexity of the Studied Concepts and Theoretical Models with the Age of the Student

2021 ◽  
pp. 132-136
Author(s):  
Robert V. Maier
Keyword(s):  
Theoretical Model ◽  
Theoretical Models ◽  
Dependency Graphs

The problem of the dependence of the didactic complexity of the studied concepts and theoretical models on the age of the student (schoolchild, student) is analysed. The complexity of a concept (term) can be characterized by the number of words from a fifth-grader’s thesaurus needed to explain its meaning. To find the complexity of a theoretical model of an object (for example, an atom), it is necessary to sum up the complexities of all the words that make up the description of the model and take into account the indicator of the variety of terms. Dependency graphs were built: 1) the complexity of the most difficult terms for understanding from the year of study; 2) the complexity of various theoretical models of the atom from the year of study at school and university. In both cases, the resulting curves are ascending, like a parabola, corresponding to an increase in complexity by almost a hundred times.

scholarly journals Coordination Numbers of Bivalent Ions in Organic Solvents

2021 ◽  
Vol 95 (10) ◽  
pp. 2059-2064
Author(s):  
M. A. Orekhov
Keyword(s):  
Experimental Data ◽  
Theoretical Model ◽  
Molecular Dynamic ◽  
Coordination Number ◽  
Organic Solvents ◽  
Organic Molecule ◽  
Dynamic Models ◽  
Coordination Numbers ◽  
A Value ◽  
Bivalent Ions

Abstract Molecular dynamic models are created for properties of bivalent ions in organic solvents. It is shown that molecules of the considered solvents bound to ions via oxygen atoms. A theoretical model is developed that describes the ion coordination number. The coordination number in this model is determined by the ratio between the sizes of the ion and the atom organic molecule bound to it. It is shown that the coordination number depends weakly on the solvent and strongly on the type of ion. A value of 0.13 nm is obtained for the effective size of an oxygen atom bound to a bivalent ion. The constructed theoretical model agrees with the results from molecular dynamic calculations and the available experimental data.

scholarly journals ANALYSIS OF SAFETY SYSTEM RELIABILITY KI HADJAR DEWANTARA MAKO KODICLATAL BUILDING TOWARDS FIRE HAZARDS PREVENTION

JOURNAL ASRO ◽  
2021 ◽  
Vol 12 (02) ◽  
pp. 10
Author(s):  
Dodiek Alfianzi ◽  
Ikhwan Syahtaria ◽  
Udisubakti Cipto Mulyono ◽  
I Made Jiwa Astika
Keyword(s):  
System Design ◽  
Management System ◽  
Fire Hazard ◽  
Inspection System ◽  
Fire Prevention ◽  
Fire Hazards ◽  
A Value ◽  
Precautionary Measures ◽  
Fire Prevention Management ◽  
In Fire

Designing a fire prevention inspection system in buildings is very necessary, to determine the level of reliability. The fire prevention management system uses the following criteria: precautionary measures and preventive supervision against fire hazards. The assessment of the system design is carried out by means of a questionnaire for respondents who understand / are experts in fire problems, and the application of the system design uses direct surveys and questionnaires to the building manager. The assessment is carried out at the smallest level. Analysis of the building reliability inspection system in fire prevention using the Analytical Hierarchy Process (AHP) method, the criteria used are: prevention, limitation and extinguishing against fire. The fire prevention management system uses the following criteria: precautionary measures and preventive supervision against fire hazards. The results of the reliability inspection of the Ki Hadjar Dewantara Mako Kodiklatal building in Surabaya with a value of 94.06% indicated that the reliability system was in the "Less Reliable" category for fire hazard prevention.   Keywords: Inspection, fire prevention, reliability.

Estimating the diffusion length in the deepest section of ice cores; A case study for MIS19 in Dome-C

2021 ◽  
Author(s):  
Thomas Laepple ◽  
Thomas Münch ◽  
Torben Kunz ◽  
Mathieu Casado ◽  
Maria Hoerhold
Keyword(s):  
Diffusion Length ◽  
Ice Core ◽  
Ice Cores ◽  
Climate Information ◽  
Climate Signal ◽  
A Value ◽  
Recovery Strategies ◽  
Length Estimate ◽  
And Diffusion

<p>To recover very old climate information from ice core records, one needs to interpret the deepest part of an ice core. As the oldest record, the Dome-C ice core can serve as an analogue for the Beyond EPICA Oldest Ice Core that is currently being drilled.<br><br>Pol et al., EPSL 2010 analyzed high resolution water isotope data from the Dome-C ice core and found evidence for a limited preservation of climate variability in the deep section of the core due to mixing and diffusion. For instance, for Marine Isotope Stage 19, the study estimated a mixing/diffusion length between 40 and 60 cm, a value more than double than what is predicted by current firn and ice diffusion models. Knowing the diffusion length is important to interpret the isotope signal and is the basis to deconvolve climate records. As a result, it is key to bridge the gap in the estimation of the diffusion length between potentially biased statistical methods and firn and ice diffusion models.<br>We review this diffusion length estimate for MIS19, and also outline a new general method how to estimate the diffusion length in highly thinned deep ice.  This approach presents an important tool for better characterizing the preservation of the climate signal in old ice and thus for designing optimal sampling and recovery strategies.</p><p> </p>

Retrieval of Bio-Geophysical Parameters from Remotely Sensing Data by Using Bayesian Methodology

2007 ◽  
pp. 222-252
Author(s):  
C. Notarnicola
Keyword(s):  
Experimental Data ◽  
Theoretical Model ◽  
Theoretical Models ◽  
Data Sets ◽  
Model Errors ◽  
Sources Of Information ◽  
Remotely Sensed Data ◽  
Bayesian Methodology ◽  
Information Models ◽  
Bayesian Methodologies

This chapter introduces the use of Bayesian methodology for inversion purposes: the extraction of bio-geophysical parameters from remotely sensed data. Multisources information, such as different polarizations, frequencies, and sensors are fundamental to the development of operationally useful inversion systems. In this context, Bayesian methodologies offer a convenient tool of combining two or more disparate sources of information, models, and data. The chapter describes the development of a general model starting from a theoretical model, including the sensor noise and the model errors, by using a Bayesian approach. Furthermore, the developed procedure is applied to some experimental data sets. The author hopes that considering theoretical models and experimental data in many different configurations can give an idea of the versatility and robustness of the Bayesian framework.

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