• Computers and Concrete
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• 제12권5호
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• pp.585-612
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• 2013

The paper presents quasi-static numerical simulations of the behaviour of short reinforced concrete beams without shear reinforcement under mixed shear-tension failure using the FEM and four various constitutive continuum models for concrete. First, an isotropic elasto-plastic model with a Drucker-Prager criterion defined in compression and with a Rankine criterion defined in tension was used. Next, an anisotropic smeared crack and isotropic damage model were applied. Finally, an elasto-plastic-damage model was used. To ensure mesh-independent FE results, to describe strain localization in concrete and to capture a deterministic size effect, all models were enhanced in a softening regime by a characteristic length of micro-structure by means of a non-local theory. Bond-slip between concrete and reinforcement was considered. The numerical results were directly compared with the corresponding laboratory tests performed by Walraven and Lehwalter (1994). The advantages and disadvantages of enhanced models to model the reinforced concrete behaviour were outlined.

• 동아시아경상학회지
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• 제3권4호
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• pp.9-15
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• 2015

The exchange rate is a very important macro variable that has influence on the whole economy and has, therefore, been the topic of many discussions amongst policymakers, academics and other economic agents. The issue of whether to have a fixed, pegged or floating exchange rate regime was highly debated during the 1970s. The purpose of this paper is to investigate what factors determine the exchange rate in Somalia. Quantitative research methodology has been employed to develop regression model using time series data for the period of 12 years. The regression model has been developed based on Quantity theory of money, purchasing power parity and uncovered interest rate parity theory. Somalia is on the countries where the highest exchange rate volatility exists; for example in 2012, the rate jumped 29% percent and two weak later dropped 21%, when Turkish humanitarian aid agencies injected the market a lot of U.S dollar. Based on my study using regression model for time series data of 12 years, the four factors are mainly attributable for the exchange rate volatility of Somalia; these factors include the balance of payment, inflation rate, money supply (mostly come from remittance and NGOs) and Bank profits.

• Journal of Information Science Theory and Practice
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• 제11권4호
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• pp.1-13
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• 2023

Being one of the first and hardest hit countries by the coronavirus, Iran still continues to preserve its place among nations with the highest rates of infection and COVID-19 related deaths. While on the surface, such worrying status evinces the failure of the authorities in handling the crisis, at deeper levels, it points to the fundamentalist nature of the government and political system of the country. In this view, the current devastating condition in Iran is a clear indication of the all-out influence of the Islamic regime's ideologies on officials' decision-making and their political agendas throughout the pandemic. Accordingly, the staterun mainstream media, as the most preeminent institution of power, have been incessantly engaged in disseminating a series of ideology-laden information around the issues concerning the coronavirus, and in line with the developing political discourses during pandemic. Far from being based on factual accounts or scientific facts, these disseminated messages inevitably grew into a source of disinformation, ultimately resulting in overall public confusion and skepticism. Through examining the data gathered from some of the most prominent online news agencies run by the government, this study identifies five major discursive trends through which the mainstream media propagated ambiguous and manipulative information about COVID-19. These findings are then explained in the light of media system dependency theory, leading to the argument that within autocratic nation-states, public reliance on media during a national/global crisis brings about new opportunities for state exploitation, and further distressing consequences for the people.

• 의료법학
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• 제9권2호
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• pp.311-338
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• 2008

This paper aims to introduce an overview of the regime of expert witness in the medical malpractice litigation, and to provide a plan of how to make it improved. In regard with medical expert witness, several problems, such as time-consuming procedure, non-neural and unclear opinion without reasons provided, have been pointed out for several years. Lack of skill of the court and plaintiff/defender to question the expert is one of many cause to lead to the above problems. What is questioned to the expert? Because expert witness is used in determining probability of negligence, questions to the expert should be selected on the grounds of whether or not to obtain opinions or facts sufficient to let the judge infer negligence in view of the theory of proof burden established by the Supreme Court. In addition, to avoid non-neutral and unclear opinion, it is necessary to question the expert clearly, specifically and scientifically.

• 소성∙가공
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• 제14권4호
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• pp.327-337
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• 2005

In the present work, the two back stress kinematic hardening models are proposed by combining Armstrong-Frederick, Phillips and Ziegler's hardening rules. Simple combination of hardening rules using simple rule of mixtures results in various evolutions of the kinematic hardening parameter. Using the combined hardening models the ultimate back stress fur the present models is also derived. The stress rate is co-rotated with respect to the spin of substructure due to the assumption of kinematic hardening rule in finite deformation regime. The work piece under consideration is assumed to consist of the elastic and the rigid plastic deformation zone. Then, the J2 deformation theory is facilitated to characterize the plastic deformation behavior under various loading conditions. The plastic deformation localization behaviors strongly depend on the constitutive description namely back stress evolution and its hardening parameters. Then, the analysis for Swift's effects under the fixed boundaries in axial directions is carried out using simple shear deformation.

• 천문학회지
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• 제38권2호
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• pp.129-133
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• 2005

The temperature (T) and entropy (S) fields of baryonic gas, or intergalactic medium (IGM), in the ACDM cosmology are analyzed using simulation samples produced by a hybrid cosmological hydrodynamic/N-body code based on the weighted essentially non-oscillatory scheme. We demonstrate that, in the nonlinear regime, the dynamical similarity between the IGM and dark matter will be broken in the presence of strong shocks in the IGM. The heating and entropy production by the shocks breaks the IGM into multiple phases. The multiphase and non-Gaussianity of the IGM field would be helpful to account for the high-temperature and high-entropy gas observed in groups and clusters with low-temperature IGM observed by Ly$\alpha$ forest lines and the intermittency observed by the spikes of quasi-stellar object's absorption spectrum.

• 한국대기환경학회지
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• 제19권6호
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• pp.733-743
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• 2003

The flow field in multiple fluid sphere systems was studied analytically. The expanded zero vorticity cell model based on Kuwabara's theory (1959) was applied and the effects of gas slippage at the collecting surface were considered. Also, the solid sphere system was extended to fluid sphere including the effects of the induced internal circulation inside the liquid droplet spheres or gas bubble systems. As a result, the obtained analytic solution was converged to the existing solutions for flow field around solid and bubble sphere systems with proper boundary conditions. Based on the resolved flow field, the terminal velocity around the collecting fluid spheres was obtained. Subsequently, this study evaluated the most general solution for flow field around the multiple fluid sphere systems. The obtained flow field in multiple fluid sphere could be used as a fundamental consideration of wet scrubber design and devices for removing particles by fluid-fluid interactions.

• 한국진공학회지
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• 제21권3호
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• pp.130-135
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• 2012

드리프트-확산 근사식을 이용한 1차원 유체 방정식으로부터 선형적 안정성 이론을 전개하여 Tosend 방전에서 전자 확산이 불안정성에 미치는 영향을 관찰하였다. 본 연구에서 관찰된 바에 따르면 Townsend 불안정성은 전자 확산과 공간 전하에 의해 형성된 전기장의 효과가 결합되어 발생하며, 공간전하에 의한 효과가 작은 영역, 즉 방전 전류가 낮은 영역에서는 전자 확산 효과가 커질수록 불안정이 더 빨리 진행된다는 것이 발견되었다.

• Interaction and multiscale mechanics
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• 제1권1호
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• pp.53-81
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• 2008

The theory of microlocal analysis of hyperbolic partial differential equations shows that the energy density associated to their high-frequency solutions satisfies transport equations, or radiative transfer equations for randomly heterogeneous materials with correlation lengths comparable to the (small) wavelength. The main limitation to the existing developments is the consideration of boundary or interface conditions for the energy and power flow densities. This paper deals with the high-frequency transport regime in coupled heterogeneous structures. An analytical model for the derivation of high-frequency power flow reflection/transmission coefficients at a beam or a plate junction is proposed. These results may be used in subsequent computations to solve numerically the transport equations for coupled systems, including interface conditions. Applications of this research concern the prediction of the transient response of slender structures impacted by acoustic or mechanical shocks.

• 미술이론과 현장
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• 제10호
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• pp.63-84
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• 2010

This essay examines how the figure of Liberty has been refashioned in the streets of post-apartheid South Africa, addressing three public art works installed in Johannesburg over the past decade: Reshada Crouse's oil painting Passive Resistance, Marlene Dumas' tapestry The Benefit of the Doubt and William Kentridge's and Gerhard Marx's sculpture Firewalker. Even as these monumental works all reprise Delacroix's Liberty on the Barricades-an icon of the city street and its revolutionary barricades-so too this trio of Liberties have become mere phantoms of their vaunted archetype. Haunted specters, they quarrel with the mythologized chimera of Liberty, taking issue with the fraught tradition of pinning regime change onto the body of the female nude. Drawing instead on South African histories of women's resistance, in which female nudity has been repeatedly marshaled as a form of dissent, the Liberties circling Johannesburg hybridize their European template with local traditions of female political opposition to colonial and postcolonial male authority.