• ETRI Journal
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• v.37 no.4
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• pp.717-726
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• 2015

In this paper, we study an asymmetric two-way relaying network where two source nodes intend to exchange information with the help of multiple relay nodes. A hybrid time-division broadcast relaying scheme with joint relay selection (RS) and power allocation (PA) is proposed to realize energy-efficient transmission. Our scheme is based on the asymmetric level of the two source nodes' target signal-to-noise ratio indexes to minimize the total power consumed by the relay nodes. An optimization model with joint RS and PA is studied here to guarantee hybrid relaying transmissions. Next, with the aid of our proposed intelligent optimization algorithm, which combines a genetic algorithm and a simulated annealing algorithm, the formulated optimization model can be effectively solved. Theoretical analyses and numerical results verify that our proposed hybrid relaying scheme can substantially reduce the total power consumption of relays under a traffic asymmetric scenario; meanwhile, the proposed intelligent optimization algorithm can eventually converge to a better solution.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.6 no.12
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• pp.3352-3365
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• 2012

Group key agreement (GKA) is a cryptographic primitive allowing two or more users to negotiate a shared session key over public networks. Wu et al. recently introduced the concept of asymmetric GKA that allows a group of users to negotiate a common public key, while each user only needs to hold his/her respective private key. However, Wu et al.'s protocol can not resist active attacks, such as fabrication. To solve this problem, Zhang et al. proposed an authenticated asymmetric GKA protocol, where each user is authenticated during the negotiation process, so it can resist active attacks. Whereas, Zhang et al.'s protocol needs a partially trusted certificate authority to issue certificates, which brings a heavy certificate management burden. To eliminate such cost, Zhang et al. constructed another protocol in identity-based setting. Unfortunately, it suffers from the so-called key escrow problem. In this paper, we propose the certificateless authenticated asymmetric group key agreement protocol which does not have certificate management burden and key escrow problem. Besides, our protocol achieves known-key security, unknown key-share security, key-compromise impersonation security, and key control security. Our simulation based on the pairing-based cryptography (PBC) library shows that this protocol is efficient and practical.

• Journal of Contemporary Eastern Asia
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• v.20 no.2
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• pp.157-173
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• 2021

In the transition to a multipolar international system, the literature has focused on great power competition while little attention has been given to the strategic possibilities of smaller states. However, as a result of globalization, states are so closely interconnected that the primary strategies of even major powers are not to achieve zero-sum solutions but to create asymmetric dependency through which they can influence the behavior of other states and non-state actors. States are assisted in this effort by a variety of tools, including setting up institutions, direct economic influence and through building different forms of infrastructure connectivity networks. By discussing asymmetric dependency situations from the perspective of the great powers, the literature presents smaller states primarily as passive actors, paralyzed by their dependence on great powers. Our paper argues that interdependence allows smaller states to effectively influence larger actors and examines strategies from which smaller states can choose in order to influence the behavior of larger states. Despite an extremely asymmetric relationship between Myanmar and China, actors in Myanmar have sought to influence China's Myanmar policy. We examine a case study of the Myitsone Dam, including Myanmar's strategic aims, chosen strategy and limitations in maneuvering space. Semi-structured interviews with local decision-makers and stakeholders are conducted in order to portray the full picture. Our study concludes that further research on the influencing strategies of small states in response to asymmetric dependence can contribute to a better understanding of the interdependence of states.

• The Journal of Fisheries Business Administration
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• v.51 no.4
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• pp.69-83
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• 2020

The purpose of this paper is to empirically investigate whether asymmetric price transmission exists in the distribution stage of farmed olive flounder market. For the analysis, time series data were used for the producer prices of Jeju and Wando, and the wholesale prices of Incheon, Hanam and Busan. Through the Granger causality test, the causal relationship from the producer price to the wholesale price was derived and the asymmetric price transmission was analyzed using the autoregressive distributed lag model (ARDL). As a result of the analysis, it was found that there is a phenomenon of 'positive asymmetric price transmission' from the producer price to the wholesale price. This result can be one evidence that excess profits are received in the intermediate distribution stage, and can be said to be a result showing the incompleteness and inefficiency of the distribution structure of the farmed olive flounder. In the future, it is required to establish an information-sharing system in all stages of production, distribution, and consumption that can create a competitive environment for distribution participants and resolve information asymmetry. Also, it is necessary to review the distribution center specializing in live fish from the viewpoint of the establishment of new distribution channels and sales diversification strategy under the rapidly changing fisheries environment.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.4
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• pp.857-861
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• 2021

The study aims to find the asymmetric effect in National Stock Exchange in which the Nifty50 is considered as proxy for NSE. A return can be stated as the change in value of a security over a certain time period. Volatility is the rate of change in security value. It is an arithmetical assessment of the dispersion of yields of security prices. Stock prices are extremely unpredictable and make the investment in equities risky. Predicting volatility and modeling are the most profuse areas to explore. The current study describes the association between two variables, namely, stock yields and volatility in equity market in India. The volatility is measured by employing asymmetric GARCH technique, i.e., the EGARCH (1,1) tool, which was used in building the study. The closing prices of Nifty on day-to-day basis were used for analysis from the period 2011 to 2020 with 2,478 observations in the study. The model arrests the lopsided volatility during the mentioned period. The outcome of asymmetric GARCH model revealed the subsistence of leverage effect in the index and confirms the impact of conditional variance as well. Furthermore, the EGARCH technique was evidenced to be apt in seizure of unsymmetrical volatility.

• Structural Engineering and Mechanics
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• v.86 no.2
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• pp.249-260
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• 2023

The uncertainties involved in structural performances are of importance when the optimum number and property of seismic retrofit devices are determined. This paper proposes a seismic retrofit design framework for asymmetric soft-first-story buildings, considering uncertainties in the soil condition and seismic retrofit device. The effect of the uncertain parameters on the structural performance is used to find a robust and optimal seismic retrofit solution. The framework finds a robust and optimal seismic retrofit solution by finding the optimal locations and mechanical properties of the seismic retrofit device for different realizations of the uncertain parameters. The structural performance for each realization is computed to evaluate the effect of the uncertainty parameters on the seismic performance. The framework utilizes parallel processing to decrease the computationally intensive nonlinear dynamic analysis time. The framework returns a robust design solution that satisfies the given limit state for every realization of the uncertain parameters. The proposed framework is applied to the seismic retrofit design of a five-story asymmetric soft-first-story case study structure retrofitted with a viscoelastic damper. Robust optimal parameters for retrofitting a structure to satisfy the limit state for the different realizations of the uncertain parameter are found using the proposed framework. According to the performance evaluation results of the retrofitted structure, the developed framework is proved effective in the seismic retrofit of the asymmetric structure with inherent uncertainties.

• The Journal of Asian Finance, Economics and Business
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• v.10 no.1
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• pp.79-89
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• 2023

The paper aims to investigate the asymmetric long-run and short-run relationships between inflation and remittance outflows in the Kingdom of Saudi Arabia (hereafter KSA) over the period 1971-2019 by using the Nonlinear Autoregressive Distributed Lag (NARDL) model. The statistical tests have supported the validity and stability of the model. The Wald F-test statistics confirm the existence of a long-run equilibrium relationship among the model variables; remittance outflows, positive (negative) shocks in inflation rates, investment, real GDP, and trade openness. Moreover, the empirical results confirm the existence of an asymmetric effect of the inflation rate on remittance outflows. The response of foreign workers to an increase in inflation rates differs from their response to a decrease in inflation rates. However, this asymmetric relationship between the increases/decreases in inflation and remittance outflows is significantly weak. The weakness of this relationship is due to the high marginal remittance propensity of migrant workers, which is explained by the low consumption propensity of foreign workers and their ability to adjust to the high cost of living due to inflation and the imposition of accompanying fees. Finally, the change in the inflation rate is not among the main factors influencing foreign remittance decisions in Saudi Arabia.

• Journal of the Society of Naval Architects of Korea
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• v.61 no.2
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• pp.68-76
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• 2024

The rotor sail is one of the representative devices in eco-friendly wind-assisted propulsion systems that have been practically applied to commercial ships. The present study proposes an asymmetric vertical folding rotor sail (AFRS) designed for small ships, featuring asymmetric geometry along the vertical direction and the function of vertical folding. To evaluate the aerodynamic performance of rotor sail, the drag, lift and lift-to-drag ratio were derived using computational fluid dynamics. The aerodynamic performance of AFRS was compared with that of normal rotor sail with different aspect ratios and spin ratios. The effect of geometric parameters on the aerodynamic performance of AFRS was assessed by varying the asymmetric diameter ratio. The maximum improvement in lift-to-drag ratio for AFRS was approximately 12% in the considered case. Additionally, the resistance is decreased when AFRS is vertically folded without rotating. Throughout the present study, improved aerodynamic and resistance performances for AFRS were confirmed, which will successfully provide additional propulsion to small ships.

• Structural Engineering and Mechanics
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• v.91 no.5
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• pp.517-526
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• 2024

Due to the asymmetric cross-section of unequal-angle steel, the application of loads can induce axial rotation, leading to a series of buckling failure behaviors. Special attention must be paid during the design process. The present study aims to analyze the structural behavior of asymmetric steel angle members under various eccentric loading conditions, considering the complex biaxial bending interaction that arises when the angle steel is connected to the panel. Several key factors are investigated in this paper, including the effects of uniaxial and biaxial eccentricity on the structural behavior and the eccentric axial compression strength of long and short legs at different load application points. Potential risks associated with the specified load points, based on the AISC specifications, are also discussed. The study observed that the strength values of the members exhibited significant changes when the eccentric load deviates from the specified point. The relative position of the eccentric load point and the slenderness ratio of the member are critical influencing factors. Overall, this research intends to enhance the accuracy and reliability of strength analysis methods for asymmetric single angle steel members, providing valuable insights and guidance for a safer and more efficient design.

• ETRI Journal
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• v.27 no.3
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• pp.289-293
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• 2005

We propose an asymmetric integral imaging method to adjust the resolution and depth of a three-dimensional image. Our method is obtained by use of two lenticular sheets with different pitches fabricated under the same F/#. The asymmetric integral imaging is the generalized version of integral imaging, including both conventional integral imaging and one-dimensional integral imaging. We present experimental results to test and verify the performance of our method computationally.