• Journal of the Korean Society of Safety
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• v.24 no.4
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• pp.104-110
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• 2009

In this driving simulation study, the impairing effects of various types of electronic devices usage(i. e., destination search by using in-vehicle navigation system, TV watching and dialing cellular phone) during driving on front-to-rear-end collision avoidance were investigated. Percentage of collisions, driving speeds when the drivers collided, and initial reaction time for collision avoidance were analyzed and compared as the dependent measures. The results indicated that (1) any types of electronic devices usage during driving induced more serious collision-related impairment than control condition where no additional task was required, and (2) in general, destination search task appeared to impair drivers collision avoidance performance more than the other task requirements in terms of percentage of collisions and initial reaction time for collision avoidance, but TV watching induced most serious collision impact. These results suggested that any types of electronic device usage could distract drivers attention from the primary task of driving, and be resulted in serious outcome in potentially risky situation of front-to-rear-end collision. In particular, mandatory use of eye-hand coordination and receiving feedback seemed to one of essential factor leading the drivers visual attentional distraction.

• Journal of Biomedical Engineering Research
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• v.33 no.3
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• pp.155-162
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• 2012

Devices to measure the blood pressure of patients are being used without any calibration in a hospital. It is an important to show consistent values when any medical devices measure the same patients regardless they are sphygmomanometer or fully automatic electronic blood pressure meter. We compared sphygmomanometer and fully automatic electronic blood pressure meters with standard digital blood pressure monitor (SDBPM) to evaluate the consistency of the small healthy subjects. We measured the blood pressure from six healthy subjects (three of 20~40 years and three of 40~60 years old). Two sphygmomanometer and two fully automatic electronic blood pressure meters were used and compared with the SDBPM. Blood pressures measured from right and left arms each and were compared. All six healthy subjects showed normal blood pressure values. In general, left blood pressure values showed higher values than right side. Comparing SDBPM, with the other monitors, the systolic pressure showed ${\pm}$ 34.8% difference and ${\pm}$ 33.3% for the diastolic pressure. Correlation between SDBPM and Sphygmomanometer was 0.59~0.71, and 0.50~0.70 for fully automated digital BP monitors. It fell in grade-D when we apply the BHS(British hypertension society). AAMI(American association for the advancement of medical instrumentation) also showed unsatisfactory results for the mean value (${\leq}$ 5 mmHg) and standard deviation (${\leq}$ 8 mmHg). We tested sphygmomanometer and fully automatic electronic blood pressure meters and compared with a standard digital blood pressure monitor. All devices showed inconsistent blood pressures. A reliable calibration system is highly needed for all devices in all hospitals.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1541_1542
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• 2009

본 논문에서는 바이오/환경센서 응용을 위해 실리콘 기판위에 나노 동공구조 백금 전극을 작동전극으로 갖는 소형화된 용존산소센서를 설계 및 제작하고 그 특성을 분석하였다. 제작된 용존산소 센서는 15 mm $\times$ 8 mm $\times$ 0.6 mm의 소형화된 크기를 가졌으며, -0.9 V의 인가전위 시에 각각 산소 포화 상태와 무산소 상태에서 2.14 mA와 0.8 mA의 환원전류 특성을 보였다. 또한, 다양한 산소 농도상태에서 각기 다른 전류응답 차이를 보였다. 이를 통해서 다양한 산소농도에 대한 센싱특성을 검증하였다. 한편, 제작된 용존산소 센서는 전극제작에 사용된 나노 동공구조 백금 전극의 높은 촉매 특성에 기인하여 90% 전류응답시간이 7초 이내로 기발표된 다른 연구들에 비해 현저히 향상된 응답특성을 보였다.

• Proceedings of the KIEE Conference
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• 2001.11c
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• pp.34-37
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• 2001

In this paper, we designed and implemented the 60W DC characteristic measurement system for semiconductor devices. The proposed system is composed of 2 SMU(Source and Measure Unit)s, 2 HPU(High power Unit)s, 2VSU(Voltage Source Unit)s, and 2 VMU(Voltage Measurement Unit)s. HPU can source/measure voltage from -200V to 200V and source/measure current from -3A to 3A within 60W. Experimental results show that the implemented system can measure the power devices such as power BJT, regulator IC, and voltage detector.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.30 no.7
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• pp.423-426
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• 2017

The designing approaches with consideration offabrication process technologies for high-frequency, high-powered, silicon-based static induction thyristors (SITH) are presented. The effects of doping concentration and thickness on the I-V characteristics and power performance of the devices are discussed. The dependence of SITH switching performances on material, geometric structure, and technological parameters isexamined by using two-dimensional simulations. Thick-epitaxy technology is found to be one of the most critical steps in realizing the proposed structure and switching times, $t_{off}$, of SITH, which may be reduced to below ${\sim}0.26{\mu}s$ for the proposed 1,700 V SITH devicesafter optimization.

• Journal of Photoscience
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• v.9 no.1
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• pp.23-28
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• 2002

In order to obtain thermal-stable, low birefringent, and low optical loss waveguiding materials, we synthesized several fluorinated poly (maleimide-co-glycidylmethacrylate)s using a pentafluorophenylmaleimide (PEM) and two kinds of methacrylate derivatives as comonomers and glycidylmethacrylate as a crosslinker. One comonomer is a linear fluorinated methacrylate (HFBM) and another is a bulky norbornane-derived methacrylate (NMMA). These copolymers could be self-crosslinked by heating due to epoxy groups of glycidylmethacrylates. As a maleimide contents increased to 50 mol%, these copolymers showed high decomposition temperatures of above 300$^{\circ}C$. The refractive index could be precisely controlled by the variation of PFM/HFBA or PFM/NMMA feed ratio in the range of 1.410∼1.508 at 643 nm. The copolymers had very low birefringence in the range of 1∼5${\times}$10$\^$-4/.

• Proceedings of the KIPE Conference
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• 2002.07a
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• pp.330-333
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• 2002

The design of high power electronic circuits and the verification of the design by practical experiments are time and cost consuming. Recently power circuit simulation technique is developing to do it easily. However, most of the simulation has used the ideal switch model consists of passive component that can not describe the physical characteristics of semiconductor devices and cannot describe the switching transient state. For the design of such power electronic circuits by the simulation, the switching transients are very important. Therefore the simulation models must describe the switching transient and the stationary behavior as precisely as possible on the hand and as fast as possible the other hand. This paper introduces the application of the physical models of power devices that are developed by TUM(Technical University of Munich, Germany) for the power electronic circuit analysis.

• Proceedings of the KIEE Conference
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• 2000.07d
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• pp.2808-2810
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• 2000

Most measuring devices are equipped with RS232 interface or GPIB interface for communicating with computers. If the measuring devices can be accessed by a server computer, the valuable information from the devices can be effectively shared with other computer via internet. VRML is a web based technology for specifying and delivering three-dimensional interactive visualizations over the internet through a web browser. This paper proposes a remote 3-dimensional monitoring system for digital multimeter equipped with RS232 interface by utilizing VRML.

• Proceedings of the KIEE Conference
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• 2005.07e
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• pp.70-72
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• 2005

Electronic control systems adopted in water treatment facilities. And many water treatment facilities are operated by electrical and electronic devices or by remote control. So those are damaged by the surge which is generated by lightning inevitably. This study is intended to measure and analyze the SPD performance tests occurred at the electrical and electronic control devices and to show the methods of the reduction when the surge is occurred suddenly.

• Proceedings of the Korean Vacuum Society Conference
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• 2007.08a
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• pp.307-307
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• 2007