• Proceedings of the KSR Conference
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• 2008.06a
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• pp.1125-1127
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• 2008

Recently, the tilting train has been developed to increase speed in conventional line. Due to global environmental changes, it is necessary to investigate quantitatively the environment of tilting train. This study evaluated the environmental impacts of tilting train to grasp a key issue environmentally. The related data were collected from bill of material (BOM). The system boundary of tilting train was determined by its cumulative weight. In addition, the $CO_2$ emission in the operation phase of tilting train was calculated. Based on this basic study, the environment of tilting train will be assessed exactly through the establishment of life cycle inventory database for its main components.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.665-666
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• 2015

In this paper, it is proposed to substitute the tilting operation device of hybrid multi-D.O.F system from three phase SPM to single phase torque actuator. When using tilting operation with three phase SPM which is appropriate for continuous rotary operation, there are disadvantages that electricity availability rate is low and controllability is difficult. On the other hand when using a single phase torque actuator instead of SPM, it is appropriate for sequential tilting, electricity availability rate is high, and it is easy to control. Thus this will have a great influence on the development and practical use of the system. This study designed a single phase torque actuator in consideration of the magnetic saturation. Also, this was verified with comparative analysis with SPM through FEM(finite element method) analysis values of the design model and test values of the manufactured model.

• Journal of the Korean Ceramic Society
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• v.36 no.7
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• pp.762-766
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• 1999

The crystal structure of A2+(Mg1/3Nb2/3)O3,(A2+=Sr2+ and Ca2+)ceramics was studied usig X-ray diffraction (XRD) and high resolution transmission electrion microscopy(HRTEM). Ba(Mg1/3Nb2/3)O3 (SMN) has the 1:2 ordered monoclinic structure which has the anti-phase tilt of octahedra. The type of tilting in SMN was considered to be a$^{\circ}$a$^{\circ}$c- or a­a­c$^{\circ}$ Ca(Mg1/3Nb2/3)O3 (CMN) also has the 1:2 ordered monoclinic structure which was distorted by the anti-phase tilt or in-phsae tilt of octahedra. A unit cell containing both the in-phase tilt axis and anti-phase tilt axis was not observed in the CMN. Therefore CMN has the mixed phase consisting of the 1:2 ordered monoclinic phase with anti-phase tilt of octahedra and the one with in -phase tilt of ocatahedra,. The anti-parallel shift of cation was also observed in the CMN.

• Journal of the Korean Ceramic Society
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• v.32 no.5
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• pp.582-586
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• 1995

The crystal structures of (Na0.3Sr0.7)(Ti0.7M0.3)O3 (M=Ta, Nb) compounds were determined using the Rietveld method. Due to the tilting of a oxygen octahedron, (Na0.3Sr0.7)(Ti0.7Nb0.3)O3 had a superlattice of doubled a, b and c of simple perovskite. The crystal structure of (Na0.3Sr0.7)(Ti0.7M0.3)O3 was tetragonal with a space group 14/mmm. The crystal structure of (Na0.3Sr0.7)(Ti0.7M0.3)O3 was a cubic with space group Pm3m, in which no tilting of oxygen octahedron was observed. The difference in the oxygen tilting of these two materials was due to the larger covalency of Nb-O bond than that of Ta-O bond, which induced a strong $\pi$Nb0 bonding in (Na0.3Sr0.7)(Ti0.7M0.3)O3. Therefore, the higher transition temperature of (Na0.3Sr0.7)(Ti0.7M0.3)O3 could be related to the larger tilting of oxygen octahedron.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.27 no.7
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• pp.612-619
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• 2016

In this paper, a dual band electrical beam tilting array antenna with bi-directional directivity is designed. Radiating element operates at dual-resonance frequencies and is designed as planar dipole using PCB. In order to tilt the main beam, the phase delay line is designed by use of only the phase shifting line of a $50\Omega$ microstrip line for broadband. The designed antenna has tilting angle of $0^{\circ}$ to ${\pm}8^{\circ}$. For validation of the designed antenna specification, the array antenna is fabricated and the performances are measured. Comparison between theory and experiment shows good agreement.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.42 no.1
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• pp.111-118
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• 2005

The shape of vertical pattern of base station antenna affects greatly quality of the communication of not only a service zone but also adjacent cells and then it is an important point to be considered in designing cell coverage. Currently type of vertical patterns to be applied to base station antenna are divided into five classes. In designing antenna, these five classes are applied solely or compositely according to the environment to be used antenna. In this paper, the dual polarized antenna for base station that is with a continuous electrical down tilting and with a shaped beam pattern, that an upper side lobe is suppressed and a lower null is filled, is designed and fabricated for synthesizing of the shape beant the pattern synthesis methods proposed by R. S. Elliott is used sequentially and for the electrical don tilting, the phased array theory is applied. Measured results show the down tilting range from 0° to 14°, the gain of Min. 13.3dBi and the upper side lobe of Max. -23dB. And we verified that upper side lobe is not to vary greatly and null filling performance is favorable overall.

• Applied Microscopy
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• v.32 no.1
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• pp.9-15
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• 2002

Microstructural investigations of $(1-x)NdAlO_3-xCaTiO_3$ (NACT) complex perovskite compounds were carried out using X-ray diffractometry, neutron diffraction and transmission electron microscopy. When $0.3{\leq}x{\leq}0.9$, NACT had not only the 1 : 1 chemical ordering of cations but also the antiphase and inphase tilting of oxygen octahedron and the antiparallel shift of cations. Both the antiphase boundaries and the ferroelastic domains were present in the microstructure. The long and straight ferroelastic domains became degenerate as x decreases. When x was smaller than 0.3, the chemical ordering was absent and the antiphase tilting of oxygen octahedron was observed. The defects like tangled dislocations and the second phase were also found in the microstructure.

• Applied Microscopy
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• v.32 no.2
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• pp.157-162
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• 2002

Microstructural investigations of $(Na_{1/2}Pr_{1/2})TiO_3$ (NPT) complex perovskite compounds were carried out using X-ray diffractometry and transmission electron microscopy. NPT had not 1:1 chemical ordering of Asite cations but had the antiphase and inphase tilting of oxygen octahedron and the antiparallel shift of cations. Both the antiphase boundaries and the ferroelastic domains were not present in the microstructure. Unidentified second phase was found in the microstructure. The measured dielectric properties were ${\varepsilon}_r=99.6,\;Q\;{\Large f}_o=1124\;GHz,\;{\tau}_{f}=-233.64ppm/^{\circ}C$.

• Korean Journal of Applied Biomechanics
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• v.17 no.2
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• pp.11-21
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• 2007

The study was undertaken to present the quantitative materials available in underwater industries, underwater rehabilitation & physical training through comparison & analysis of effects contributing to propulsion of COG by types of fin-kick in underwater activities. For this 3D cinematography was performed for the skilled subjective and conclusions obtained on the basis of analysis of kinematic variables were as follows. In temporal variable the delay in the order of flutter>side>dolphin kick in elapsed time by total & phase resulted in longer sliding phase by larger fin kick of extension & flexion of both leg and thus more contributed in propulsion of COG. than those of the otherwise. In linear variable the contribution ratio to the result of propulsion of COG in both propulsive(mean $35.39{\pm}7.93cm$ in Y axis) and sliding phases(mean $66.36{\pm}11.01cm$ in Y axis)was shown to be order of flutter>dolphin>side fin kick. the maximum velocity of COG in Y direction was showed in both propulsive and sliding phases, and the contribution ratio to the propulsion of COG was in the order of flutter$\geq$dolphin>side fin kick. In angular variable the Significant difference in angle of leg joint by types of fin kick in both leg was showed but no routine order. The Significant difference in angular velocity of leg joint by types of fin kick in both leg was showed in the order of flutter>dolphin$\geq$side fin kick in propulsive but no in sliding phase. The Fluid resistance by tilting angle of trunk in both propulsive and sliding phase was decreased in the order of flutter>dolphin$\geq$side fin kick and tilting angle of trunk of the skilled was smaller than that of the unskilled in difference of maximum mean 7.97degree and minium mean 2.06degree. In summary of the above, It will desirable fin kick type because of more contribution to COG propulsion by the velocity & displacement in Y-axis and less fluid resistance by tilting angle of trunk and larger angular velocity in the case of more delayed in elapsed time of propulsive phase than that of the otherwise.

• Journal of the Korean Physical Society
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• v.73 no.10
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• pp.1529-1534
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• 2018

We used in-situ synchrotron X-ray scattering to investigate phase transformations of octahedral tilted monoclinic $SrRuO_3$ (MSRO) and tetragonal SRO (TSRO) thin films on $SrTiO_3$ (STO) substrates. The octahedral tilted MSRO thin films were highly crystalline and the monoclinic distortion angle was $0.45^{\circ}$. The phase transition temperature from the MSRO to TSRO phase occurred at approximately $200^{\circ}C$ as a second order transition. Conversely, no phase transformations of the TSRO thin film occurred within the range from RT to $250^{\circ}C$. The octahedral $RuO_6$ rotation was strongly affected by the phase transformation in the SRO thin films.