• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.35 no.5
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• pp.53-61
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• 2003

In this study a model for the drying process in paper production plants was developed based on the mass and heat balances around drying cycles. Relationships for the heat transfer coefficients between the web and the air as well as between the drying cylinder and the web were extracted from the closed-loop plant operation data. It was found that the heat transfer coefficients could be represented effectively in terms of moisture content, basis weight and reel velocity. The effectiveness of the proposed model was illustrated through numerical simulations. From the comparison with the operation data, the proposed model represents the paper plant being considered with sufficient accuracy.

• Transactions on Electrical and Electronic Materials
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• v.8 no.1
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• pp.21-25
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• 2007

A two-dimensional TCAD MEDICI simulator was used to examine the voltage transfer characteristics, on-off switching properties and latch-up of a CMOS inverter as a function of the n-channel length and doping levels. The channel in a LDMOSFET encloses a junction-type source and is believed to be an important parameter for determining the circuit operation of a CMOS inverter. The digital logic levels of the output and input voltages were analyzed from the transfer curves and circuit operation. The high and low logic levels of the input voltage showed a strong dependency on the channel length, while the lateral substrate resistance from a latch-up path in the CMOS inverter was comparable to that of a typical CMOS inverter with a guard ring.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.4
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• pp.903-911
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• 1994

This study addresses the phenomena of bubbling, icing, eruption, component varieties of the evaporated natural gas, and volumetric heat transfer coefficients obtained during the operation of a proposed LNG evaporator between LNG and water in direct contact. In the present investigation, the explosive and eruption phenomena within the water column were not observed during the entire operation of the heat exchanger. Compared with the natural gas produced by conventional LNG evaporator, the analysis of the gas produced by the direct contact LNG evaporator shows that nitrogen, methane, and ethane components were reduced by 0.002~0.007mol%(4~14%), 1.6~1.92mol%(1.9~2.3%) and 0.17~1.28mol%(1.1~8.4%) respectively, while the moisture content was rather increased by 0.51~0.76mol%. The maximum volumetric heat transfer coefficient of the direct contact heat exchanger was found to be $21, 800kW/m^3\cdotK$.

• Journal of Communications and Networks
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• v.15 no.4
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• pp.398-406
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• 2013

In this paper, we investigate two types of in-phase and quadrature-phase (IQ) data transfer methods for cloud multiple-input multiple-output (MIMO) network operation. They are termed "after-precoding" and "before-precoding". We formulate a cloud massive MIMO operation problem that aims at selecting the best IQ data transfer method and transmission strategy (beamforming technique, the number of concurrently receiving users, the number of used antennas for transmission) to maximize the ergodic sum-rate under a limited capacity of the digital unit-radio unit link. Based on our proposed solution, the optimal numbers of users and antennas are simultaneously chosen. Numerical results confirm that the sum-rate gain is greater when adaptive "after/before-precoding" method is available than when only conventional "after-precoding" IQ-data transfer is available.

• Transactions of Materials Processing
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• v.15 no.3 s.84
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• pp.183-188
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• 2006

Heat transfer coefficients have great influence on finite element analysis results in elevated temperature forging processes. Experimentally calculated contact heat transfer coefficient is not suitable for one-time finite element analysis because analyzed temperature will be appeared to be too low. To get contact heat transfer coefficient for one-time finite element analysis, tool temperature in operation was measured with thermocouple and repeated finite element analysis was performed with experimentally calculated contact and cooling heat transfer coefficient. Surface temperature of active tool was obtained comparing measurement and analysis results. Contact heat transfer coefficient for one-time finite element analysis was achieved analyzing surface temperature between repeated finite element analysis and one-time finite element analysis results.

• Journal of the Korean Institute of Navigation
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• v.11 no.1
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• pp.39-65
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• 1987

Since the middle of 1950's, containerization has been rapidly spread over the world in virtue of great merits providing to interensts, and the fundamental changes in port management and prot operations are resulted. As the container terminal is a complex system which is consisted of various subsystems, the treatment for improving the productivity is required in a comprehensive fashion, both in each of its parts and as an integrated system. This paper aims to make an intensive analysis of the Busan Container Terminal system, especially focusing on its subsystems such as ship operation system, storage system and transfer system. First of all, the intrinsic capacity of various subsystems is calculated and it is checked whether the current operation is being performed effectively through the formal analysis. Secondly, the suggestion is presented to improve the operation by considering the throughput that the port of Busan will have to accept in the near future. The results are as follows; 1) As the inefficiency is due to the imbalance between various subsystems at Busan terminal, transfer equipment level must be up to 31% for straddle carrier and 67% transfer crane above all. 2) The yard capacity must be increased by reducing the free dwell time of containers in order to accept the traffic volume smoothly in the near future. 3) The better way to reduce the port congestion is to change berthing rule from the FIFP to the Pre-allocated system by considering the ship arrival pattern.

• The Transactions of the Korean Institute of Power Electronics
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• v.22 no.5
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• pp.423-430
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• 2017

This paper proposes a control methodology for a high efficiency operation of an inductive power transfer (IPT) converter by combining full bridge (FB) and half bridge (HB) controls. To apply the proposed control to the IPT converter, the characteristics of each control method are analyzed. By examining the output voltages of the IPT converter and a theoretical loss analysis, the control shifting points between FB and HB controls are evaluated in accordance with the coupling coefficients and the load. Based on the control shifting points, the FB-HB control algorithm is implemented. By applying FB-HB control, high efficiency operation at the light load condition can be achieved.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.45 no.4
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• pp.146-153
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• 2008

In this paper, a integrated phase-locked loop(PLL) as a clock multiphase generator for a high speed serial link is designed. The designed PLL keeps the same bandwidth and damping factor by using programmable current mirror in the whole operation frequency range. Also, the close-loop transfer function and VCO's phase-noise transfer function of the designed PLL are obtained with circuit netlists. The self impedance on board-mounted chip is calculated according to sizes and positions of decoupling capacitors. Especially, the detailed self-impedance analysis is carried out between frequency ranges represented the maximum gain in the close-loop transfer function and the maximum gain in the VCO's phase noise transfer function. We shows PLL's jitter characteristics by decoupling capacitor's sizes and positions from this result. The designed PLL has the wide operating range of 0.4GHz to 2GHz in operating voltage of 1.8V and it is designed 0.18-um CMOS process. The reference clock is 100MHz and PLL power consumption is 17.28mW in 1.2GHz.

• The Korean Society of Law and Medicine
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• v.14 no.2
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• pp.281-313
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• 2013

A physician has to do his best for the better treatment of his patiensts. But, if a physician cannot remedy his patients because of the lack of hospital facilities, the lack of medical knowledge and etc., the physician must transfer his patients to another suitable hospital immediately. This is called the duty of interhospital transfer of patients. The necessity of interhospital transfer of patients is primarily ocurred in emergency medical care situations. The Supreme Court Decision 2010DO7070 delivered on April 29, 2010 is one of the important decisions related to the duty of interhospital transfer of patients. The Supreme Court ruled that there were the physician's medical malpractice and the causation between the physician's medical malpractice and the death of patient, as the physician has left the patient without due observations for 1 hour and 30 minutes after the caesarean operation inspite of mass bleeding during the operation, and has transferred the patient to another suitable hospital later. And the Supreme Court ruled that the transferring physician has to explain the situation of the patient in detail to the physician being transferred. I agree with the Supreme Court Decision. As decided by the Supreme Court, physicians will treat their patients more carefully and in case of necessity for transfer, physicians will transfer their patients with more caustion. However, the study for this issue should be continued hereafter because concrete standards are not given to lawers and physicians just by the Supreme Court Decisions itself.

• Archives of Plastic Surgery
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• v.32 no.5
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• pp.573-581
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• 2005

Breast cancer is the second leading cause of death in woman. Unfortunately, the frequency of breast cancer and mastectomy are increasing in Korea. This paper introduces the breast reconstruction by use of pectoralis major muscle transfer with breast implant for small size defect after skin sparing mastectomy for more satisfaction. We reviewed 24 consecutive patients who underwent breast reconstruction by pectoralis major muscle transfer with implant and only breast implant in Dong-A University from April 2002 to March 2004. The patient's age ranged between 29 and 54 years with mean of 42.3 years. We used pectorals major muscle transfer with breast implant in 12 patients and breast implant alone in 12 patients as control. The follow-up period of patients ranged from 10 months to 3 years with mean of 18.5 months. The points of comparison with control group reconstructed by breast implant alone were doctor and patient satisfaction score, operation time, duration of admission, amount of drainage, complication and satisfaction according to mass location. In conclusion, there is no difference with control group in the point of operation time, mount of drainage, duration of admission. And there is higher level of doctor's and patient's satisfaction in group reconstructed by pectoralis major muscle transfer with breast implant than implant only group. Especially, pectoralis major muscle transfer with breast implant was especially necessary for the defect in upper lateral quadrant of the breast to get more satisfaction. The advantage of pectoralis major muscle transfer with breast implant is prevention of the protruding and palpability of implant and aesthetically satisfactory result by intraoperative modification of breast shape.