• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.34 no.2
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• pp.36-47
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• 2006

The process of dual spin turn maneuver is introduced for attitude acquisition or recovery from flat spin state of a satellite. The physical principle of momentum transfer during dual spin turn is explained clearly. The case studies of special dual spin turn, in addition to the conventional dual spin turn, that are known as an acceptable cases, are performed to investigate the principle of dual spin turn and to provide a physical insight as well as the solution of dual spin turn. This study is done based on case-study simulation, which includes two-state control scheme composed of open-loop maneuver and energy dissipation device. Furthermore, we investigate the stability for the verification of all control cases after implementing two-stage control. We also provide the simulation scenario of flat spin recovery using dual spin turn method as an example.

• 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.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.10a
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• pp.485-486
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• 2012

• Proceedings of the IEEK Conference
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• 1999.11a
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• pp.271-274
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• 1999

This paper proposes a simple architecture of digital dividing block in dual-modulus prescaler phase-locked loop used in the wireless communication. Proposed architecture eliminates a swallow counter in the conventional one and demonstrates the advantages in reducing the power consumption and the gate-counts. Therefore, it is suitable for small die area and low power applications. The circuit is designed in a standard 0.35${\mu}{\textrm}{m}$ CMOS process.

• Proceedings of the IEEK Conference
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• 1999.11a
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• pp.275-278
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• 1999

In this paper, Dual PFD(Phase Frequency Detector) with improved phase locking time is proposed. The proposed PFD consists of positive and negative edge triggered D flip-flop. In order to confirm the characteristics of proposed PFD, HSPICE simulations are performed using a 0.25${\mu}{\textrm}{m}$ CMOS process. As a result of simulations, the proposed PFD has a characteristic of fast phase locking time with dead zone free.

• Journal of the Korean Home Economics Association
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• v.32 no.4
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• pp.97-116
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• 1994

The purpose of the stud is to present an model of the distress process for dual-earner couples. For the data set 340 husbands and wives in dual-earner families living in Pusan were chosen. The questionnaire was composed of Family Stressor Scale Family Resources Scale, Distress Scale. The data were analyzed with the SPSS statistical pacakage using t-test the one-rather than husband. And cothestion, adaptability and the level of stress recognition are important factors affecting the level of physical and psychological distress directly.

• Journal of International Area Studies (JIAS)
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• v.22 no.1
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• pp.67-90
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• 2018

France has allowed a deprivation of nationality for terrorism since 1996 Law. After then, a series of law revision (1998, 2006 law and 2010, 2015-2015 reform tries) have not only linked an act of terror with nationality deprivation but also put the dual national and their deprivation at the centre of dispute. Both 2010 Immigration Law by Sarkozy and 2015-2016 constitutional amendment by Hollande had been not adopted but have combined immigrants and security issue together by firmly solidifying the relationship between dual national and terrorist. Especially in 2015-2016, the constitutional amendment that failed to be adopted has extended a state of emergency and left the nationality deprivation of dual national as controversial issue. After over 4 months of discussion, the amendment that contains a clause of a state of emergency and extension plan for nationality deprivation was abolished but the dual national issues which had been non-politicized has now become politicized, defined as security issues and finally securitized. It shows very two-stage process of securitization argued by Copenhagen school including Buzan. The importance of securitization notion by Copenhagen school lies on the fact that it scrutinizes the constructive elements of the process of securitization. The concept of securitization allows us to see the problem of the process that defines a non-politicized issue as security one by making it political matter. Applying this process of securitization into the controversy of nationality deprivation of dual nationals in France, we can find out the development of non-controversial and non-politicized dual national issues into social agenda by politicization through speech-act or announcement effect.

• Journal of Welding and Joining
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• v.15 no.4
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• pp.99-108
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• 1997

Analytical model for the temperature distribution and the cooling rate of weld in dual beam laser welding is presented for investigating the possibility of controling the cooling rate. The model is based on the solutions to the problem of heat flow due to the distributed and line heat sources for preheating and welding respectively in plates with finite thickness. The effects of beam power, beam distribution parameter, interbeam distance, and welding speed on the resulting temperature distribution and cooling rate are presented. The cooling rates of dual beam laser weld at the weld centerline under the investigated conditions are reduced to as one third of those of welds which were produced by single beam laser. And it appeared that the cooling rate of dual beam laser weld is strongly dependent on the process parameters of preheating laser beam power and welding speed.

• Journal of Korean Society of Water and Wastewater
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• v.19 no.1
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• pp.92-97
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• 2005

This research is to investigate the effect of the dual coagulant using inorganic coagulants($AICl3{\cdot}6H2O$) and polymer on the coagulant process. Jar-test was conducted by using Kaolin injected raw water. PDA(Photometric Dispersion Analyzer) equipment in order to analyze the size of the particles and the characteristics of the shapes. The change in the rate of sample ores' residual deposited after coagulants were also compared. According to the result derived from this experiment, the concentration of inorganic coagulant reduced 50% and the residual was lower by using dual coagulants compared to using single coagulant. However the dual coagulant required sufficient mixing time, and affected particle characteristics, with the effect of the injection order of coagulants, the simultaneous injection of inorganic coagulant and polymer showed the most effective in the particle removal.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1998.06a
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• pp.41-44
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• 1998

Dual mode resonators were fabricated using high temperature superconductor. The deposited material was $Y_1Ba_2Cu_3O_{7-x}$(YBCO) on MgO(100) substrate using pulsed laser deposition. Dual mode resonators were patterned by standard photolithography process and wet etching. At the back-side of the substrate, the ground plane with the metal layer of Ti and Ag was fabricated. The transition temperatures of YBCO films were 85-88 K, and network analyzer was used for testing the performance of the resonators. The input/output feedline angles of each resonator were $60^{\circ}$and $100^{\circ}$. The resonant frequency of resonators was 10 GHz. In this paper, dual mode resonator was fabricated for the application of satellite communication.