• Journal of the Korea Institute of Military Science and Technology
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• v.22 no.3
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• pp.353-359
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• 2019

In this study, a aerodynamic loads prediction to design a deploying device of folded fin was introduced. In general, resultant flow conditions around the fin are used to obtain deploying moments and required energy. However, when it comes to the air vehicles launched from a mobile platform, more specific flow conditions can be provided. With the conditions, the design criteria can be calculated more realistically. In this study, therefore, aerodynamic moments induced by aerodynamic loads and energy required in deployment were calculated using wind-over-deck(WOD) velocity, combination of a platform velocity and a wind velocity. For the calculation, wind tunnel test was conducted on various angle of attack, side slip angles, and folding angles. It was found that the aerodynamic moments and the energy required in deployment using the non-uniform flow due to the velocity components were less than those using the uniform flow without the components.

• Advances in aircraft and spacecraft science
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• v.10 no.5
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• pp.419-437
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• 2023

This paper presents the study of the effects of rigid-body motion simultaneously with the presence of the effects of temporal variation due to the existence of morphing speed on the aeroelastic stability of the two-stage telescopic wings, and hence this is the main novelty of this study. To this aim, Euler-Bernoulli beam theory is used to model the bending-torsional dynamics of the wing. The aerodynamic loads on the wing in an incompressible flow regime are determined by using Peters' unsteady aerodynamic model. The governing aeroelastic equations are discretized employing a finite element method based on the beam-rod model. The effects of rigid-body motion on the length-based stability of the wing are determined by checking the eigenvalues of system. The obtained results are compared with those available in the literature, and a good agreement is observed. Furthermore, the effects of different parameters of rigid-body such as the mass, radius of gyration, fuselage center of gravity distance from wing elastic axis on the aeroelastic stability are discussed. It is found that some parameters can cause unpredictable changes in the critical length and frequency. Also, paying attention to the fuselage parameters and how they affect stability is very important and will play a significant role in the design.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.41 no.6
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• pp.502-508
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• 2013

Various combinations of cartridge and orifice were applied for ground ejection tests of a gliding bomb model equipped with a new guidance kit. Larger diameter of orifice made larger ejection force at each of bomb racks. Normal operations of the wing deploying mechanism and the devices inside of the bomb model were confirmed. Also high speed video data showed that pitch angle of the gliding bomb varied due to the ejection force.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.34 no.8
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• pp.1-7
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• 2006

In the present study, A 3-D chimera technique for overlapped bodies in relative motion is studied using unstructured meshes. If all node points of a mesh element at solid boundary are in another body, this element is excluded from computational domain. For computation of unsteady flow, non-active cells have proper variables using interpolation and extrapolation. These variables are used in next time step. The motion of a launching trajectory ejected from a wing and the motion of deploying fins of a trajectory which have not been simulated are computed to conform practicality of this technique.

• Journal of Contemporary Eastern Asia
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• v.19 no.2
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• pp.125-147
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• 2020

On the World Refugee Day in 2017, Yao Chen, a Chinese actress, philanthropist, and social media influencer, posted messages in her Weibo in support of the United Nations Refugee Agency (UNHCR). Yet, social media users quickly interpreted this supportive message of the refugee program as encouraging people to "accept and receive refugees" (jieshou nanmin) into China. Particularly, the category of Middle Eastern refugees elicited most criticism in China's cyberspace. As the inclusion of refugees is an integral part of immigrant multiculturalism, this article examines the limits of multicultural imagination of refugees―particularly those from the Middle Eastern and North Africa―in contemporary China. I argue that the limits of multicultural imagination in contemporary China is profoundly shaped by an intricate interweaving of domestic policies and global imaginaries toward refugees. By deploying a mixed methodology, such limits are examined from legal-institutional, ideological, and sociocultural perspectives. More specifically, three interrelated aspects will be highlighted in the article: (1) the global circulation of right-wing populism imaginaries, and their entanglements with the anti-Muslim sentiments in contemporary China; (2) the current insufficiency of the legal-institutional framework regarding refugees and asylum-seekers, which needs to be contextualized in China's modern history of dealing with refugee issues; (3) population politics, the rise of Han-centric nationalism, and their constraining impact on the interpretation of historical events related to cultural diversity. In conclusion, this article also offers potential implications for further examining the different yet potentially intersected genealogies of multicultural imaginaries beyond the Middle Eastern and North African refugees in Asia.