• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.23 no.6
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• pp.421-429
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• 2011

Experimental and theoretical studies on cooling performance of two-channel thermoelectric air-cooling system in parallel flow are conducted. The effects of operating temperature to physical properties of thermoelectric module (TEM) are experimentally examined and used in the analysis of an air-cooling system considering thermal network and energy balance. The theoretical predicted temperature variation and cooling capacity are in good agreement with measured data, thereby validating analytic model. The heat absorbed rate increases with increasing the voltage input and decreasing thermal resistance of the system. The power consumption of TEM is linearly proportional to mean temperature differences due to variations of the physical properties on operation temperature of TEM. Furthermore thermal resistance of hot side has greater effects on cooling performance than that of cold side.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.sup2
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• pp.1-5
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• 2016

To reduce tobacco use and related harm in Korea, telephone based cessation services (Quitlines) began full operation to provide regular behavioral counseling for smoking cessation in 2006. After registration in the cessation program, at least 21 calls per year are given to each client to help quit and encourage maintenance. Tailored programs for males, females, and adolescent smokers have been offered taking into account smokers' characteristics and smoking behavior. Mailing self-help quit packs and e-mail and SMS services are allowable as additional services.A total of 23,201 smokers were registered on the Quitline program from 2006 to 2014. In 2014, an average of 13,343 calls per month have been received by 28 coaches, the 1 year abstinence rate of clients is 26%, and clients' satisfaction rate is 81.6%. After introduction of the call system in 2007, client convenience and effective operations have been achieved with high technology support of a computer-based telephone system. Systematic education and evaluation programs for quit coaches have contributed to quality assurance of the services. Currently, research into development of new programs and evaluation of Quitline performance is being undertaken. A Comprehensive Multi-channel Cessation Center (CMCC) has been suggested and is now planned as a next step in the national program for smoking cessation.

• JSTS:Journal of Semiconductor Technology and Science
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• v.10 no.4
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• pp.265-275
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• 2010

In this work, reliable methodology for device design is presented. Based on this method, the underlap length has been optimized for minimizing the gateinduced drain leakage (GIDL) in a 22-nm node 4-terminal (4-T) silicon-on-insulator (SOI) fin-shaped field effect transistor (FinFET) by TCAD simulation. In order to examine the effects of underlap length on GIDL more realistically, doping profile of the source and drain (S/D) junctions, carrier lifetimes, and the parameters for a band-to-band tunneling (BTBT) model have been experimentally extracted from the devices of 90-nm channel length as well as pnjunction test element groups (TEGs). It was confirmed that the underlap length should be near 15 nm to suppress GIDL effectively for reliable low standby power (LSTP) operation.

• Korean Journal of Veterinary Research
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• v.45 no.4
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• pp.581-585
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• 2005

The purpose of this study is to establish the analgesic effects of electroacupuncture for Korean native goat. Electroacupuncture was applied to the 6 Korean native goats. In 3 of them, rumenotomy was performed, and in the other 3, laparotomy was done. The analgesic induction time was 15 to 30 minutes. The acupoints used were Tian-ping (Celestial Peace, GV-5), Bai-hui (Hundred Meetings, GV-20), left 13th thoracic nerve and left 3rd lumbar nerve. Electroacupuncture was performed in lateral recumbency. Needles were inserted 1-2 cm deep, and connected to the electroacupuncture apparatus. The electrical stimulation condition was 30 Hz and 2-6 volts. Initially, the voltage of analgesia mode was maximized in each channel. And, the output was slowly reduced to the critical point that goats could tolerate without obvious discomfort or pain. Surgical operation was done successfully under electroacupuncture analgesia in 6 Korean native goats. In addition, the changes of temperature, heart rate and respiratory rate were studied during acupuncture analgesia. For 3 months after surgery, no experimental animals showed clinical problem in 6 Korean native goats.

• Korean Journal of Clinical Laboratory Science
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• v.54 no.2
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• pp.157-162
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• 2022

The purpose of the direct cortical and subcortical stimulation technique is to prevent false positives caused by transcranial electrical motor evoked potentials (TceMEP) in surgery on patients with brain tumors that have occurred around the motor cortex and to preserve the correct mapping of motor areas during surgery and the corticospinal tract. In addition, it reduces the trial and error that occurs during the intraoperative neurophysiological monitoring (INM) process and minimizes the test time, so that accurate information is communicated to the surgeon with quick feedback on the test results. The most important factors of this technique are, first, examination at a stimulus threshold of a certain intensity, and second, maintaining anesthesia depth at an appropriate level to prevent false positives from occurring during surgery. The third is the installation of a multi-level channel recording electrode on the opposite side of the area of operation to measure the TceMEP waveform and the response to direct cortical and subcortical stimulation in as many muscles as possible. If these conditions are maintained, it is possible to predict causes that may occur in other factors, not false positives, from the INM test.

• Progress in Superconductivity
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• v.9 no.1
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• pp.50-55
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• 2007

We have installed a 61-channel magnetocardiography (MCG) system inside a magnetically shielded room (MSR) with a size of $2.4\;m\;{\times}2.4\;m\;{\times}2.4\;m$. The MCG system consists of 1st-order axial gradiometers containing double relaxation oscillation SQUIDs (DROSs) with pick-up coils of a base line of 70 mm. The MSR holds a shielding factor of 50 at 0.1 Hz and 10000 at 100 Hz, when its door in the middle on a front wall is closed. On opening the MSR door, we have obtained the characteristics of the MCG system with a 2.9 Hz noise generated from an air conditioning unit at 13 m distance off the MSR. In an open-door MSR ($140^{\circ}$ opening), a noise at the center channel increases up to $700\;fT/Hz^{l/2}$ at 2.9 Hz and $1.7\;pT/Hz^{1/2}$ at 60 Hz. MCG signals for a healthy human do not show distortion until the door opens to $45^{\circ}$, but show the effect of noise when the door opens further at $90^{\circ}$ and $140^{\circ}$. With the door opens to $45^{\circ}$, MCG measurement can be performed with ease of door operation and without creating claustrophobia for the patient.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.17 no.6
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• pp.83-88
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• 2017

In this paper, a 3-port waveguide circulator of Ka-band millimeter-wave for isolation between transmit channel and receive channel at high power transmit mode is designed and fabricated for the seeker of the guided missile and circulator performance is verified through the S-parameter, high power and operation temperature test. At the configuration design, interface design between a seeker antenna and the circulator is considered and half-height of standard waveguide is applied for minimum and light weight body. The shape of permanent magnet and ferrite is optimized by simulation and tuning dielectrics at each port are placed for the best performance. In Fc(center frequency)${\pm}1000MHz$, designed waveguide circulator has below -20 dB return loss, below 0.5 dB insertion loss and below -23 dB isolation. It is found that circulator characteristics is similar to design results.

• Progress in Superconductivity
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• v.11 no.2
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• pp.152-157
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• 2010

We have fabricated the low noise liquid helium(LHe) dewar with a different shape of thermal shield to apply the 64-channel SQUID(Superconducting Quantum Interference Device) gradiometer. The first shape of thermal shield was made of an aluminum plate with a wide width of 100 mm slit and the other shape was modified with a narrow width of 20 mm slit. The two types of dewars were estimated by comparing the thermal noise and the signal-to-noise ratio(SNR) of magnetocardiography(MCG) using the $1^{st}$ order SQUID gradiometer system cooled each dewar. The white noise was different as a point of the dewar. The noise was increased as close as the edge of dewar, and also increased at the thermal shield with the more wide width slit. The white noise of the dewar with thermal shield of 100 mm slit was 6.5 fT/$Hz^{1/2}$ at the center of dewar and 25 fT/$Hz^{1/2}$ at the edge, and the white noise of the other one was 3.5 - 7 fT/$Hz^{1/2}$. We measured the MCG using 64-channel SQUID gradiometer cooled at each LHe dewar and compared the SNR of MCG signal. The SNR was improved of 10 times at the LHe dewar with a modified thermal shield.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.9A
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• pp.719-726
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• 2009

CR systems performs spectrum sensing operation to detect the appearance of primary users. However, since it is not feasible to do spectrum sensing and data transmission simultaneously, they typically operate alternatively in a time domain. There have been an effort(8) to investigate the optimal spectrum sensing duration for maximum throughput for the scheme with cooperative spectrum sensing. This is based on an assumption that the communication channels between each secondary user and the fusion center are ideal and does not consider the effects of transmission error. Motivated by this, we here model the channels as binary symmetric channels and examined its effect on the maximum throughput and the associated optimal sensing duration. Analysis shows that the performance degradation due to the transmission error is smaller for the case of using the AND fusion rule than for the OR fusion rule.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.12 no.2
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• pp.62-68
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• 1998

In this paper, we proposed the design of the intelligent traffic control system by using multiprocessor architecture. The inter-processor communication of the architecture is implemented by sharing the serial communication channel. In comparing the conventional traffic control system using single processor architecture, the proposed system uses multiple processors controlling the sub systems such as the signal lights, traffic measurement unit, auxiliary signal lights and peripherals. The main processor controls the communication among the processors and the communication protocol link to the central control center at remote site. The proposed architecture reduces the load and simplifies the program of each processor and enables the real time processing of the add-on features of intelligent traffic control systems. The architecture is implemented and the common channel inter-processor communications and the real time operation is experimented .experimented .