• International Journal of Naval Architecture and Ocean Engineering
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• v.8 no.6
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• pp.563-576
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• 2016

The flight deck of an aircraft carrier is relatively vulnerable compared to its hull, as the damage of some subsystems on the flight deck may cause the carrier losing its operational capability. Therefore, this work aims to represent a simulative method for evaluating the resistance of the flight deck's operational capability in the condition that the aircraft carrier is together with its strike group and the enemy uses the anti-ship missiles with the cluster warheads to attack. In the simulations, the susceptibility of the carrier and the vulnerability of the aircraft guarantee resources are gained. Then, with the help of the closed queuing network, the residual sortie generation rate can be solved, which reflects the flight deck's residual operational capability. The results have proven that the flight deck is of strong resistance to these attacks while it is very sensitive to the loss of some key aircraft guarantee resources.

• Journal of Institute of Control, Robotics and Systems
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• v.20 no.11
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• pp.1085-1091
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• 2014

This paper presents the guidance and control design for automatic carrier landing of a UAV (Unmanned Aerial Vehicle). Differently from automatic landing on a runway on the ground, the motion of a carrier deck is not fixed and affected by external factors such as ship movement and sea state. For this reason, robust guidance/control law is required for safe shipboard landing by taking the relative geometry between the UAV and the carrier deck into account. In this work, linear quadratic optimal controller and longitudinal/lateral trajectory tracking guidance algorithm are developed based on a linear UAV model. The feasibility of the proposed control scheme and guidance law for the carrier landing are verified via numerical simulations using X-Plane and Matlab/simulink.

• Journal of the Korean Chemical Society
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• v.30 no.3
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• pp.327-332
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• 1986

Spatial (radial and height) distribution of electron number density is measured for an inductively coupled plasma under five operating conditions: (1) no carrier gas, (2) carrier gas without aerosel, (3) carrier gas with aerosol, (4) carrier gas with desolvated aerosol, and (5) carrier gas with aerosol and excess lithium. A complete RF power mapping of electron density is obtained. The plasma electrons for a typical analytical torch are observed to be hollow at the radial center in the region close to the induction coil, but diffuse rapidly toward the center in the higher region of the plasma. The presence of excess Li makes no significant change in the electron density profiles. The increases in the RF power levels increase the values of electron density uniformly across the radial coordinate.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.14 no.1
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• pp.92-97
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• 2015

The design of the glass-carrier was studied using simulations of the temperature distribution of an ITO deposition inline-sputter process. The temperature distribution was simulated in Heating Chamber 7, and in the ITO Deposition Chambers 8 and 9. The temperature distribution of the glass sheets was low in both the lower and upper lines. Moreover, it was observed that the temperature in Chamber 8 significantly affected the temperature in Chamber 9, and that the latter was hotter. The rear of the chambers were subjected to more heating than the fronts, so the temperature range at the back was wider. Redesigning the shape of the carrier made it possible to load more glass sheets on the glass carrier, and to make deposits on the ITO glass at higher temperature, over a wider area.

• KSBB Journal
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• v.30 no.3
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• pp.114-118
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• 2015

In this study, we have developed a microbe-carrier that combined Desulfovibrio desulfuricans and zeolite for removal of Zn and As in contaminated seawater. Desulfovibrio desulfuricans, one of the sulfate-reducing bacteria (SRB) microorganism was exhibited stable growth characteristics in highly salted water and strong resistance to Zn and As contaminated seawater. Moreover, zeolites are one of the most useful carrier to remove heavy metals from wastewaters. The results showed that SRB immobilized zeolite carrier can enhance removal ratio of Zn and As. In addition, heavy metals tended to be better removed in medium at conditions of $37^{\circ}C$. In case of heavy metal concentration, they were effectively removed ranging from 50 to 100 ppm. These results show that SRB-zeolite carriers hold great potential to remove cationic heavy metal species from industrial wastewater in marine environment.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38A no.6
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• pp.512-519
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• 2013

In this paper, we propose a novel unambiguous correlation function for composite binary offset carrier (CBOC) signal tracking. First, we observe that a sub-carrier of CBOC signal is seen as a sum of four partial sub-carriers, and generate four partial-correlations composing the CBOC autocorrelation. Then, we obtain an unambiguous correlation function with a sharp main-peak by re-combining the partial correlations. From numerical results, we confirm that the proposed unambiguous correlation function offers a better tracking performance than the conventional correlation functions in terms of the tracking error standard deviation and multipath error envelope.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.17 no.12
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• pp.1264-1270
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• 2004

A fast switching thyristor with a superior trade-off property between the on-state voltage drop and the turn-off time could be fabricated by the proton irradiation method. After making symmetric thyristor dies with a voltage rating of 1,600 V from 350 $\mu$m thickness of 60 $\Omega$ㆍcm NTD-Si wafer and 200 $\mu$m width of n-base drift layer, the local carrier lifetime control by the proton irradiation was performed with help of the HI-13 tandem accelerator in China. The thyristor samples irradiated with 4.7 MeV proton beam showed a superior trade-off relationship of $V_{TM}$ = 1.55 V and $t_{q}$ = 15 $\mu$s attributed to a very narrow layer of short carrier lifetime(～1 $\mu$s) in the middle of its n-base drift region. To explain the small increase of $V_{TM}$ , we will introduce the effect of carrier compensation at the low carrier lifetime region by the diffusion current.ffusion current.t.

• Proceedings of the KIEE Conference
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• 1998.07d
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• pp.1367-1369
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• 1998

To achieve the ULSI goals of higher density, greater performance and operation speed have been scaled down. However, the reduction of channel length cause undesirable problems such as drop of punchthrough voltage, hot-carrier degradation and high leakage current, etc.. It is shown that the device characteristics depend on process parameters. In this Paper, we catched hold of trends of hot-carrier effects and punchthrough voltages due to variation of some process parameters such as LDD doses(P), spacer lengths, channel doses($BF_2$) and $V_T$ adjusting channel implantation energies using design trend curve (DTC). As the LDD and channel doses increased, hot-carrier phenomena became more severe, and punchthrough voltage was decreased. It were represented that punchthrough and hot carrier effects were critically depend on LDD and channel doses.

• Journal of the Society of Naval Architects of Korea
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• v.53 no.4
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• pp.282-289
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• 2016

Traditional construction method of the stern tube is difficult to control the process and needs excessive working hours. Recently in order to resolve these issues, stern tube unit has been installed for some commercial vessels. The stern tube unit is a monolithic structure of bush and related components. The purpose of this study is to carry out a feasibility study for application of the stern tube unit for a 174K twin skeg LNG carrier. In this study, a 19,000 TEU container carrier installing the stern tube unit has been selected to compare with the deformations of stern for a 174K twin skeg LNG carrier.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.39 no.11
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• pp.40-46
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• 2002

A MEMS(Micro Electro Mechanical System) package using a doped-silicon(Si) carrier for coplanar microwave and millimeter-wave integrated circuits is proposed in order to reduce parasitic problems of leakage, coupling and resonance. The proposed carrier scheme is verified by fabrication and measuring a GaAs CPW(Coplanar Waveguide) on the three types of Si-carriers(gold-plated high resistivity, lightly doped, high resistivity). The proposed MEMS package using the lightly doped(15 ${\Omega}{\cdot}$) Si-carrier shows parasitic-free performance since the lossy Si-carrier effectively absorbs and suppresses the resonant leakage.