scholarly journals DEM-FDM Coupled Numerical Study on the Reinforcement of Biaxial and Triaxial Geogrid Using Pullout Test

2021 ◽  
Vol 11 (19) ◽  
pp. 9001
Author(s):  
Jianjun Fu ◽  
Junfeng Li ◽  
Cheng Chen ◽  
Rui Rui
Keyword(s):  
Numerical Study ◽  
Interaction Mechanism ◽  
Coupled Model ◽  
Deformation Characteristics ◽  
Pullout Tests ◽  
Different Types ◽  
Simulation Results ◽  
The Relationship ◽  
Similar Deformation ◽  
Better Than

The key to modeling the interlocking of geogrid-reinforced ballast is considering both the continuous deformation characteristics of the geogrid and the discontinuity of the ballast particles. For this purpose, pullout tests using biaxial and triaxial geogrids were simulated using the coupled discrete element method (DEM) and finite difference method (FDM). In this coupled model, two real-shaped geogrid models with square and triangular apertures were established using the solid element in FLAC3D. Meanwhile, simplified shaped clumps were used to represent the ballast using PFC3D. The calibration test simulation showed that the accurately formed geogrid model can reproduce the deformation and strength characteristics of a geogrid. The pullout simulation results show that the DEM-FDM method can well predict the relationship between pullout force and displacement, which is more accurate than the DEM method. For ballast particles of 40 mm in size, both the experiment and simulation results showed that the triaxial geogrid of 75 mm is better than the 65-mm biaxial geogrid . In addition, the DEM-FDM method can study the interaction mechanism between the particles and the geogrid from a microscopic view, and also reveal the similar deformation behavior of the geogrid in the pullout process. Therefore, the DEM-FDM coupled method can not only investigate the interlocking mechanism between the ballast and particles but can also provide a great method for evaluating the performance of different types of geogrids.

Scale-dependent merging of baroclinic vortices

1994 ◽  
Vol 264 ◽  
pp. 81-106 ◽  
Author(s):  
J. Verron ◽  
S. Valcke
Keyword(s):  
Numerical Simulations ◽  
Critical Point ◽  
Lower Layer ◽  
Interaction Mechanism ◽  
Competitive Effects ◽  
Different Types ◽  
Shape Effects ◽  
Baroclinic Vortices ◽  
The Relationship ◽  
Stratified Model

The influence of stratification on the merging of like-sign vortices of equal intensity and shape is investigated by numerical simulations in a quasi-geostrophic, two-layer stratified model. Two different types of vortices are considered: vortices defined as circular patches of uniform potential vorticity in the upper layer but no PV anomaly in the lower layer (referred to as PVI vortices), and vortices defined as circular patches of uniform relative vorticity in the upper layer but no motion in the lower layer (referred to as RVI vortices). In particular, it is found that, in the RVI case, the merging behaviour depends strongly on the magnitude of the stratification (i.e. the ratio of internal Rossby radius and vortex radius). The critical point here appears to be whether or not the initial eddies have a deep flow signature in terms of PV.The specific phenomenon of scale-dependent merging observed is interpreted in terms of the competitive effects of hetonic interaction and vortex shape. In the case of weaker stratification, the baroclinic structure of the eddies can be seen as dominated by a mechanism of hetonic interaction in which bottom flow appears to counteract the tendency of surface eddies to merge. In the case of larger stratification, the eddy interaction mechanism is shown to be barotropically dominated, although interface deformation still determines the actual eddy vorticity profile during the initialization stage. Repulsion (hetonic) effect therefore oppose attraction (barotropic shape) effects in a competitive process dependent on the relationship between the original eddy lengthscale and the first internal Rossby radius.A concluding discussion considers the implications of such analysis for real situations, in the ocean or in the laboratory.

scholarly journals BER Performance Analysis of Non-Coherent Q-Ary Pulse Position Modulation Receivers on AWGN Channel

Sensors ◽  
2021 ◽  
Vol 21 (18) ◽  
pp. 6102
Author(s):  
Xianhua Shi ◽  
Yimao Sun ◽  
Jie Tian ◽  
Maolin Chen ◽  
Youjiang Liu ◽  
...  
Keyword(s):  
Gaussian Noise ◽  
Additive White Gaussian Noise ◽  
Theoretical Formula ◽  
Pulse Position Modulation ◽  
Error Performance ◽  
Optimal Receiver ◽  
Awgn Channel ◽  
Simulation Results ◽  
The Relationship ◽  
Better Than

This paper introduces the structure of a Q-ary pulse position modulation (PPM) signal and presents a noncoherent suboptimal receiver and a noncoherent optimal receiver. Aiming at addressing the lack of an accurate theoretical formula of the bit error rate (BER) of a Q-ary PPM receiver in the additive white Gaussian noise (AWGN) channel in the existing literature, the theoretical formulas of the BER of a noncoherent suboptimal receiver and noncoherent optimal receiver are derived, respectively. The simulation results verify the correctness of the theoretical formulas. The theoretical formulas can be applied to a Q-ary PPM system including binary PPM. In addition, the analysis shows that the larger the Q, the better the error performance of the receiver and that the error performance of the optimal receiver is about 2 dB better than that of the suboptimal receiver. The relationship between the threshold coefficient of the suboptimal receiver and the error performance is also given.

Examination of a non-orthogonal multiple access scheme for next generation wireless networks

2020 ◽  
pp. 154851292095127
Author(s):  
Ravi Shankar
Keyword(s):  
Multiple Access ◽  
High Performance ◽  
High Reliability ◽  
Wireless Systems ◽  
Bandwidth Efficiency ◽  
Fifth Generation ◽  
Access Scheme ◽  
Simulation Results ◽  
The Relationship ◽  
Better Than

Non-orthogonal multiple access (NOMA) is an important technique that enables fifth-generation (5G) wireless systems to satisfy the heterogeneous requirements of enhanced fairness, huge connectivity, high performance, low latency, and high reliability. In this work, the NOMA technique for 5G wireless communication is investigated, and considering user fairness limitations, the channel capacity has been optimized. Also, bandwidth efficiency (BE) is examined and the relationship between BE and energy efficiency (EE) is derived. Simulation results show that without wasting power the near user gets preference in power allocation when the target rate is greater than 6.4 bps/Hz. Also, when the target rate [Formula: see text] 6.4 bps/Hz, the outage performance of the near user will improve and the performance of the far user will remain the same. Also, it is demonstrated that cooperative NOMA outperforms all other techniques. Simulation outcomes confirm that NOMA performs better than conventional multiple access techniques in terms of EE and BE.

scholarly journals Experimental and Numerical Study of Octagonal Composite Column Subject to Various Loading

2017 ◽  
Author(s):  
Mehdi Ebadi Jamkhaneh ◽  
Mohammad Ali Kafi
Keyword(s):  
Numerical Study ◽  
Slenderness Ratio ◽  
Compressive Loading ◽  
Axial Loading ◽  
Experimental Tests ◽  
Composite Column ◽  
Concrete Confinement ◽  
Steel Column ◽  
Different Types ◽  
The Relationship

In this study, experimental tests of the behaviour of steel and partially encased composite (PEC) columns subjected to compressive loading is performed. Evaluation of this type of composite column under axial loading and numerical analysis of its behaviour under combined torsional and axial loading are the main objectives of this study. At first, a parametric study of PEC columns under axial loading was performed in order to find the relationship between flange slenderness ratio of steel column section and concrete confinement. Width-to-thickness ratio of the flange, diameter and spacing of the transverse links were considered as variables in this study. It was observed that dimension of transverse links had almost no effect on the capacity of the specimens, however smaller transverse links spacing increased both capacity and deformability of the specimens. The comparison of the code equations given in CSA S16-14 and EN 1994-1-1 revealed that the equation in CSA S16-14 underestimates the capacity. Furthermore, different types of retrofit of cross-shaped steel column including concrete encasement, use of stiffener plates and transverse links were investigated in this research. Results revealed that concrete confinement and use of transverse links had respectively the most and the least effect on increasing torsional capacity of the specimens.

Plato on Pure Pleasure and the Best Life

Phronesis ◽  
2014 ◽  
Vol 59 (2) ◽  
pp. 113-142 ◽  
Author(s):  
Emily Fletcher
Keyword(s):  
Good Life ◽  
Human Life ◽  
Detailed Examination ◽  
The Good Life ◽  
Human Beings ◽  
Instrumental Value ◽  
Different Types ◽  
The Relationship ◽  
Better Than ◽  
Positive Evaluation

Abstract In the Philebus, Socrates maintains two theses about the relationship between pleasure and the good life: (1) the mixed life of pleasure and intelligence is better than the unmixed life of intelligence, and: (2) the unmixed life of intelligence is the most divine. Taken together, these two claims lead to the paradoxical conclusion that the best human life is better than the life of a god. A popular strategy for avoiding this conclusion is to distinguish human from divine goods; on such a reading, pleasure has merely instrumental value, and it benefits human beings only as a result of their imperfect nature. I argue that certain ‘pure’ pleasures are full-fledged, intrinsic goods in the Philebus, which are even worthy of the gods (thus Socrates ultimately rejects thesis 2). This positive evaluation of pure pleasure results from a detailed examination of pleasure, which reveals that different types of pleasures have fundamentally different natures.

scholarly journals Study on the Relationship between Drivers’ Personal Characters and Non-Standard Traffic Signs Comprehensibility

2021 ◽  
Vol 18 (5) ◽  
pp. 2678
Author(s):  
Antoni Wontorczyk ◽  
Stanislaw Gaca
Keyword(s):  
Personality Traits ◽  
Traffic Signs ◽  
Human Errors ◽  
Professional Drivers ◽  
The Road ◽  
Unusual Combination ◽  
Different Types ◽  
Road Space ◽  
The Relationship ◽  
Better Than

Drivers’ incorrect perception and interpretation of the road space are among reasons for human errors. Proper road markings are elements improving perception of road space. Their effectiveness relies on traffic participants receiving the provided information correctly. The range of signs used is constantly expanding and unusual situations in traffic require use of non-standard signs or an unusual combination of existing standard signs. The aim of this study was to explore the level of comprehensibility of four different types of non-standard signs. The relationship between the level of comprehensibility of these signs and personality traits of the drivers was also studied. A total of 369 drivers were tested using a questionnaire to analyze the traffic signs comprehensibility and Five Factor Inventory (NEO-FFI). The obtained results indicate that symbolic signs, unlike symbolic and text ones, are much better comprehended by drivers. Men comprehend the significance of non-standard symbolic regulatory signs better than women. Higher level of comprehensibility of symbolic and text regulatory signs is shown by older, better educated drivers and professional drivers. The study found there is a link between personality traits of the driver and the comprehensibility of symbolic regulatory signs.

scholarly journals Application of Data Assimilation and the Relationship between ENSO and Precipitation

2021 ◽  
Vol 26 (1) ◽  
pp. 24
Author(s):  
Sittisak Injan ◽  
Angkool Wangwongchai ◽  
Usa Humphries
Keyword(s):  
Data Assimilation ◽  
Correlation Coefficient ◽  
Southern Oscillation ◽  
Three Dimensional ◽  
Coupled Model ◽  
Heavy Precipitation ◽  
Sea Surface ◽  
Intermediate Coupled Model ◽  
The Relationship ◽  
Better Than

Climate change in Thailand is related to the El Niño and Southern Oscillation (ENSO) phenomenon, in particular drought and heavy precipitation. The data assimilation method is used to improve the accuracy of the Ensemble Intermediate Coupled Model (EICM) that simulates the sea surface temperature (SST). The four-dimensional variational (4D-Var) and three-dimensional variational (3D-Var) schemes have been used for data assimilation purposes. The simulation was performed by the model with and without data assimilation from satellite data in 2011. The result shows that the model with data assimilation is better than the model without data assimilation. The 4D-Var scheme is the best method, with a Root Mean Square Error (RMSE) of 0.492 and a Correlation Coefficient of 0.684. The relationship between precipitation in Thailand and the ENSO area in Niño 3.4 was consistent for seven months, with a correlation coefficient of −0.882.

Numerical Study of Characteristics of Burning Phenomena in Equidistant Square Arrayed n-Heptane Fires

2014 ◽  
Author(s):  
Koyu Satoh ◽  
Naian Liu ◽  
Xiaodong Xie ◽  
Wei Gao
Keyword(s):  
Heat Flux ◽  
Burning Rate ◽  
Radiative Heat ◽  
Numerical Study ◽  
Simulation Method ◽  
Flame Length ◽  
Simulation Software ◽  
Radiative Heat Flux ◽  
Simulation Results ◽  
The Relationship

Merging of large-scale city fires and forest fires causes rapid acceleration of fire growth. Once a merging fire occurs, it becomes more difficult to suppress, with greater potential damages. In particular, merging fires may induce fire whirls in windy conditions. However, the details of interactions in multiple fires that cause fire merging have not been fully clarified. For the interactions in multiple fires, the inter-fire distance among fires greatly affects the merging phenomenon. The objective of this paper is to examine the detailed merging conditions, particularly the burning rate increase and total heat release rate, by numerical simulation of reduced scale fires. The burning behavior of n-heptane in n × n fire arrays is examined, using the fire simulation software, FDS by NIST. In addition, another simple model is employed. The number of array matrix, n, is varied, together with the inter-fire distance. The simulation results show that there are considerable differences between both simulations and experiments. However, the differences between the simpler simulation Method II and experiments are fewer than the simulation Method I. The following possibilities are considered: (1) The oil pan size affects the difference, but the results between simulations and experiments are so large. (2) The grid size for simulations may have some effects on the simulation results due to the resolution, (3) the experimental results may not always be precise, since the burning rates in the experiments are measured by the burn-out time and (4) the wind caused by merging fires may reduce the radiative heat flux to the adjacent fuel. The relationship between flame length and burning rate and the relationship between flame length and radiative heat flux are well-correlated.

Relationship between Auditory Discrimination, Articulation Stimulability, and Consistency of Misarticulation

1975 ◽  
Vol 40 (1) ◽  
pp. 171-177 ◽  
Author(s):  
Laura L. Lapko ◽  
Nicholas W. Bankson
Keyword(s):  
Screening Test ◽  
Speech Therapy ◽  
Nonsense Syllable ◽  
First Grade ◽  
Auditory Discrimination ◽  
The Other ◽  
Self Monitoring ◽  
Different Types ◽  
The Relationship ◽  
Better Than

A study was conducted to measure the relationship between auditory discrimination, articulation stimulability, and consistency of misarticulation. Data were based on the Carter-Buck Nonsense-Syllable Imitation Test for stimulability of /s/, the McDonald Deep Test of Articulation which measured consistency of misarticulation of /s/, and the Farquhar-Bankson In-depth Test of Auditory Discrimination which measured external and internal auditory discrimination of /s/. Ss were 25 kindergarten and first grade children with normal hearing and intelligence. No S had received any speech therapy. Each S misarticulated a minimum of three /s/ items on the McDonald Screening Test of Articulation. No more than one phoneme was misarticulated in addition to misarticulation of /s/. A significant correlation between the child's ability to discriminate his own production of /s/ (internal or self-monitoring) and the consistency of misarticulation of /s/ was obtained, as well as one between the consistency of misarticulation of /s/ and the stimulability of /s/. No statistically significant correlations were found between the other variables. A low non-significant correlation was found between the stimulability of /s/ and internal discrimination abilities. Different types of discrimination tasks were of varying difficulty. Performance on external discrimination items was better than for internal discrimination items.

THEORY OF LAW AND PHILOSOPHY OF LAW AS THEORETICAL DISCOURSES: SPECIFICS AND RELATIONSHIP

2020 ◽  
pp. 9-17
Author(s):  
Вадим Леонидович Афанасьевский
Keyword(s):  
Scientific Knowledge ◽  
Scientific Theory ◽  
Theoretical Concept ◽  
Philosophy Of Law ◽  
The West ◽  
Scientific Creativity ◽  
Key Characteristics ◽  
Different Types ◽  
Theory Of Law ◽  
The Relationship

В статье анализируется проблема взаимоотношений философии права и научной теории права. Рассматриваемая проблема стала особенно актуальной в российском образовательном пространстве в связи с введением после длительного перерыва в государственный образовательный стандарт магистратуры по юриспруденции учебной дисциплины «Философия права». Автор статьи в качестве базисного принимает тезис, согласно которому философия права, являясь сферой философской мысли, и теория права как область научного социогуманитарного знания представляют собой разные типы теоретического дискурса. Исходя из этого, в статье выстраивается теоретическая концепция, согласно которой задачей философии права как философского типа мышления является конструирование или экспликация онтологических, эпистемологических, аксиологических, феноменологических оснований для формирования и функционирования научных теоретико-правовых и историко-правовых построений. Для реализации поставленной в статье задачи подробно рассматриваются ключевые характеристики как теории философского типа, так и идеалов, норм и характеристик научного знания. Выявленное различие экстраполируется на взаимоотношение теории права как продукта научного творчества и философии права как конструкции, задающей базовые мировоззренческие смыслы. В качестве примера выработанных философией права и государства оснований научных теорий прогресса, государства, морали и права, автор приводит взгляды мыслителей западноевропейской философской классики: Т. Гоббса, Ж.-Ж. Руссо, И. Канта, Г.В.Ф. Гегеля. Именно их философские концепции предопределили образы теоретико- и историко-правовых учений XVIII, XIX, XX и даже начала XXI в. Таким образом, отношение философии права и теории права выстраивается по «вертикали»: от онтологического основания к возведению теоретико-правовых и историко-правовых научных построений. The article analyzes the problem of the relationship between the philosophy of law and the scientific theory of law. The problem under consideration has become especially urgent in the Russian educational space in connection with the introduction of the Philosophy of Law discipline master's degree in law after a long break. The author of the article takes as the basis the thesis that the philosophy of law, being the sphere of philosophical thought, and the theory of law as a field of scientific socio-humanitarian knowledge are different types of theoretical discourse. Based on this, the article builds a theoretical concept according to which the task of the philosophy of law as a philosophical type of thinking is the construction or explication of ontological, epistemological, axiological, phenomenological grounds for the formation and functioning of concrete scientific theoretical and legal and historical and legal constructions. To implement the task posed in the article, the key characteristics of both a theory of a philosophical type and ideals, norms and characteristics of scientific knowledge are examined in detail. The revealed difference is extrapolated to the relationship between the theory of law as a product of scientific creativity and the philosophy of law as a construction that sets basic philosophical meanings. As an example of the foundations of the scientific theories of progress, state, morality and law developed by the philosophy of law and the state, the author gives the views and thinkers of the West European philosophical classics T. Hobbes, J.-J. Russo, I. Kant, G.V.F. Hegel. It was their philosophical concepts that predetermined the images of theoretical and historical-legal doctrines of the XVIII, XIX, XX and even the beginning of the XXI centuries. Thus, the attitude of the philosophy of law and the theory of law is built along the «vertical»: from the ontological foundation to the construction of theoretical and historical and historical legal scientific constructions.

Sign in / Sign up

Export Citation Format

Share Document