• Journal of Space Technology and Applications
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• v.2 no.1
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• pp.13-29
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• 2022

Recently, the number of space objects around the Earth has increased rapidly, necessitating systematic space risk management. This paper proposes a dual-mode framework for assessing the risk of collision between space objects. The proposed framework consists of microscopic and macroscopic modes. The former focuses on one-to-one collision events, and the latter assesses the overall collision risk inside a cell located in space. Two risk assessment case studies using the proposed two modes demonstrate the effectiveness of the proposed framework.

• Journal of Navigation and Port Research
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• v.32 no.8
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• pp.629-636
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• 2008

Dual Mode Trailer(DMT) systems are significantly considered as future transportation technique particularly to eliminate complicated job process in the railroad based transportation and reduce relevant logistic cost in economic viewpoint. This paper presents survey of Dual Mode Trailer(DMT) systems in terms of technical applicability in domestic industry, technical trends, etc. We provide several DMT systems addressed until now and propose suitable framework of them to our nation.

• Steel and Composite Structures
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• v.37 no.4
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• pp.447-462
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• 2020

In this paper, a simplified seismic design method for low-rise dual frame-steel plate shear wall (SPSW) structures is proposed in the framework of performance-based seismic design. The dynamic response of a low-rise structure is mainly dominated by the first-mode and the structural system can be simplified to an equivalent single degree-of-freedom (SDOF) oscillator. The dual frame-SPSW structure was decomposed into a frame system and a SPSW system and they were simplified to an equivalent F-SDOF (SDOF for frame) oscillator and an equivalent S-SDOF (SDOF for SPSW) oscillator, respectively. The analytical models of F-SDOF and S-SDOF oscillators were constructed based on the OpenSees platform. The equivalent SDOF oscillator (D-SDOF, dual SDOF) for the frame-SPSW system was developed by combining the F-SDOF and S-SDOF oscillators in parallel. By employing the lateral force resistance coefficients and seismic demands of D-SDOF oscillator, the design approach of SPSW systems was developed. A 7-story frame-SPSW system was adopted to verify the feasibility and demonstrate the design process of the simplified method. The results also show the seismic demands derived by the equivalent dual SDOF oscillator have a good consistence with that by the frame-SPSW structure.

• Journal of Mechanical Science and Technology
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• v.14 no.8
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• pp.845-850
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• 2000

We consider the problem of determining the singular stresses and electric fields in a piezoelectric ceramic strip containing a Griffith crack under in-plane normal loading within the framework of linear piezoelectricity. The potential theory method and Fourier transforms are used to reduce the problem to the solution of dual integral equations, which are then expressed to a Fredholm integral equation of the second kind. Numerical values on the field intensity factors are obtained, and the influences of the electric fields for PZT-6B piezoelectric ceramic are discussed.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.6
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• pp.3735-3742
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• 2013

Background: Cardamom (Elettaria cardamom), also known as "Queen of Spices", has been traditionally used as a culinary ingredient due to its pleasant aroma and taste. In addition to this role, studies on cardamom have demonstrated cancer chemopreventive potential in in vitro and in vivo systems. Nevertheless, the precise poly-pharmacological nature of naturally occurring chemo-preventive compounds in cardamom has still not been fully demystified. Methods:In this study, an effort has been made to identify the proapoptopic, anti-inflammatory, anti-proliferative, anti-invasive and anti-angiogenic targets of Cardamom's bioactive principles (eucalyptol, alpha-pinene, beta-pinene, d-limonene and geraniol) by employing a dual reverse virtual screening protocol. Experimentally proven target information of the bioactive principles was annotated from bioassay databases and compared with the virtually screened set of targets to evaluate the reliability of the computational identification. To study the molecular interaction pattern of the anti-tumor action, molecular docking simulation was performed with Auto Dock Pyrx. Interaction studies of binding pose of eucalyptol with Caspase 3 were conducted to obtain an insight into the interacting amino acids and their inter-molecular bondings. Results:A prioritized list of target proteins associated with multiple forms of cancer and ranked by their Fit Score (Pharm Mapper) and descending 3D score (Reverse Screen 3D) were obtained from the two independent inverse screening platforms. Molecular docking studies exploring the bioactive principle targeted action revealed that H- bonds and electrostatic interactions forms the chief contributing factor in inter-molecular interactions associated with anti-tumor activity. Eucalyptol binds to the Caspase 3 with a specific framework that is well-suited for nucleophilic attacks by polar residues inside the Caspase 3 catalytic site. Conclusion:This study revealed vital information about the poly-pharmacological anti-tumor mode-of-action of essential oils in cardamom. In addition, a probabilistic set of anti-tumor targets for cardamom was generated, which can be further confirmed by in vivo and in vitro experiments.

• Advances in aircraft and spacecraft science
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• v.10 no.1
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• pp.1-18
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• 2023

This paper investigates the integrated control of an air-breathing hypersonic vehicle considering the safety of propulsion system under acceleration. First, the vehicle/engine coupling model that contains a control-oriented vehicle model and a quasi-one-dimensional dual-mode scramjet model is established. Next, the coupling process of the integrated control system is introduced in detail. Based on the coupling model, the integrated control framework is studied and an integrated control system including acceleration command generator, vehicle attitude control loop and engine multivariable control loop is discussed. Then, the effectiveness and superiority of the integrated control system are verified through the comparison of normal case and limiting case of an air-breathing hypersonic scramjet coupling model. Finally, the main results show that under normal acceleration case and limiting acceleration case, the integrated control system can track the altitude and speed of the vehicle extremely well and adjust the angle deflection of elevator to offset the thrust moment to maintain the attitude stability of the vehicle, while assigning the two-stage fuel equivalent ratio to meet the thrust performance and safety margin of the engine. Meanwhile, the high-acceleration requirement of the air-breathing hypersonic vehicle makes the propulsion system operating closer to the extreme dangerous conditions. The above contents demonstrate that considering the propulsion system safety will make integrated control system more real and meaningful.