48,623 research outputs found

    Seismic Earth Pressure Development in Sheet Pile Retaining Walls: A Numerical Study

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    The design of retaining walls requires the complete knowledge of the earth pressure distribution behind the wall. Due to the complex soil-structure effect, the estimation of earth pressure is not an easy task; even in the static case. The problem becomes even more complex for the dynamic (i.e., seismic) analysis and design of retaining walls. Several earth pressure models have been developed over the years to integrate the dynamic earth pressure with the static earth pressure and to improve the design of retaining wall in seismic regions. Among all the models, MononobeOkabe (M-O) method is commonly used to estimate the magnitude of seismic earth pressures in retaining walls and is adopted in design practices around the world (e.g., EuroCode and Australian Standards). However, the M-O method has several drawbacks and does not provide reliable estimate of the earth pressure in many instances. This study investigates the accuracy of the M-O method to predict the dynamic earth pressure in sheet pile wall. A 2D plane strain finite element model of the wall-soil system was developed in DIANA. The backfill soil was modelled with Mohr-Coulomb failure criterion while the wall was assumed behave elastically. The numerically predicted dynamic earth pressure was compared with the M-O model prediction. Further, the point of application of total dynamic force was determined and compared with the static case. Finally, the applicability of M-O methods to compute the seismic earth pressure was discussed

    Exact solution of DND_N type quantum Calogero model through a mapping to free harmonic oscillators

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    We solve the eigenvalue problem of the DND_N type of Calogero model by mapping it to a set of decoupled quantum harmonic oscillators through a similarity transformation. In particular, we construct the eigenfunctions of this Calogero model from those of bosonic harmonic oscillators having either all even parity or all odd parity. It turns out that the eigenfunctions of this model are orthogonal with respect to a nontrivial inner product, which can be derived from the quasi-Hermiticity property of the corresponding conserved quantities.Comment: 16 page

    Stretching Homopolymers

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    Force induced stretching of polymers is important in a variety of contexts. We have used theory and simulations to describe the response of homopolymers, with NN monomers, to force (ff) in good and poor solvents. In good solvents and for {{sufficiently large}} NN we show, in accord with scaling predictions, that the mean extension along the ff axis f\sim f for small ff, and f2/3\sim f^{{2/3}} (the Pincus regime) for intermediate values of ff. The theoretical predictions for \la Z\ra as a function of ff are in excellent agreement with simulations for N=100 and 1600. However, even with N=1600, the expected Pincus regime is not observed due to the the breakdown of the assumptions in the blob picture for finite NN. {{We predict the Pincus scaling in a good solvent will be observed for N105N\gtrsim 10^5}}. The force-dependent structure factors for a polymer in a poor solvent show that there are a hierarchy of structures, depending on the nature of the solvent. For a weakly hydrophobic polymer, various structures (ideal conformations, self-avoiding chains, globules, and rods) emerge on distinct length scales as ff is varied. A strongly hydrophobic polymer remains globular as long as ff is less than a critical value fcf_c. Above fcf_c, an abrupt first order transition to a rod-like structure occurs. Our predictions can be tested using single molecule experiments.Comment: 24 pages, 7 figure

    Electronic sports and traditional sports:a comparative analysis

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    Abstract. This study studies the relationship between electronic sports and traditional sports in terms of economic characteristics. In recent years, electronic sports or eSports are gradually viewed as a nascent industry. The exponential growth of electronic sports has led to several studies analyzing its relation to traditional sports. In this thesis, their relationship is reviewed under economic terms. In the first chapter, industry background and history of eSports is provided. Next, the growth rate is presented in terms of revenue, audience base, prize pool, and consumer awareness. The three future scenarios of eSports are then introduced. Electronic sports are predicted to take one of the three forms: “as a counterculture or alternative to the modern sport, as part of the hegemony of sport or as the future hegemonic sport”. The feasibility of each scenario is then evaluated, and among the three, the second scenario — as part of the hegemony of sport is considered the most plausible option. The second part of this thesis deals with the previous literature review in the field of the traditional sport. By applying the same standards and theoretical approaches, electronic sports are put under the same examination. The purpose of this chapter is to provide the structure of electronic sport by segments and types of services/ goods that eSports offer to consumers. Prior research in economics analysis on sport and recreation have classified traditional sport as a commodity. Electronic sport, in the same manner, can also be viewed as a commodity. In chapter three, economic characteristics of traditional sports and eSports are compared. One important finding that can be found in this part is the socio-economic factors that affect consumer demand for eSports. On analyzing the determinants of demand for eSports, age, gender, income, employment status are factors with the most influential impact. Time, on the other hand, is regarded as a constraint. In the last part of the thesis, by imposing the two-stage model used by sports economists, the impact of determinants of demand on eSport participation and participation frequency are examined. To gather the data, an online survey is created, and the data is analyzed by using SPSS software (version 25.0). The result resemblances those of traditional sports in prior studies, marking the similarities between the two. One novel finding is the distinction between factors affecting demand for gaming and for eSports. Such a result rules out the inherent stigma of eSports being interchangeable to gaming. In fact, the result strengthens the previous prediction of electronic sports as part of the hegemony of sport. The thesis ends with a summary of findings, limitations of this research, and the call for further research

    Multi-source in DF cooperative networks with the PSR protocol based full-duplex energy harvesting over a Rayleigh fading channel: performance analysis

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    Due to the tremendous energy consumption growth with ever-increasing connected devices, alternative wireless information and power transfer techniques are important not only for theoretical research but also for saving operational costs and for a sustainable growth of wireless communications. In this paper, we investigate the multi-source in decode-and-forward cooperative networks with the power splitting protocol based full-duplex energy harvesting relaying network over a Rayleigh fading channel. In this system model, the multi-source and the destination communicate with each other by both the direct link and an intermediate helping relay. First, we investigate source selection for the best system performance. Then, the closed-form expression of the outage probability and the symbol error ratio are derived. Finally, the Monte Carlo simulation is used for validating the analytical expressions in connection with all main possible system parameters. The research results show that the analytical and simulation results matched well with each other.Web of Science68327526
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