• Proceedings of the Korean Magnestics Society Conference
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• 2004.12a
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• pp.187-188
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• 2004

• Journal of Radiation Protection and Research
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• v.5 no.1
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• pp.42-47
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• 1980

• Proceedings of the Korea Water Resources Association Conference
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• 2005.09b
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• pp.936-937
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• 2005

• Journal of Welding and Joining
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• v.19 no.3
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• pp.252-254
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• 2001

• Proceedings of the Korea Water Resources Association Conference
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• 2003.05b
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• pp.851-854
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• 2003

• Journal of Sensor Science and Technology
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• v.19 no.1
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• pp.36-42
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• 2010

This paper describes a multi channel measurement system which can measure the cellular respiration level in a solution containing cells by using a Clark-type sensor with the solution temperature control unit. The Clark-type sensor can measure the cellular respiration level in the solution because it can measure the reduction current depending on the dissolved oxygen level in the solution. This measurement system was maintained the temperature within ${\pm}0.1^{\circ}C$ of the setting temperature value by on/off control method in order to measure the precise cellular respiration level. The measurement system showed that the applied voltage to the working electrode was very stable(-0.8 V$\pm$ 0.0071 V) by using proportional control method. From the current measurement, the response time and the linearity correlation coefficient were 25 sec and 0.94, respectively, which are very close to the results of the commercial product. Using this system and the fabricated Clarktype sensor, the average ratio of the uncoupled OCR(oxygen consumption rate) to the coupled OCR was 1.35 and this is almost the same as that obtained from a commercial systems.

• Journal of the Institute of Convergence Signal Processing
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• v.8 no.3
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• pp.171-177
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• 2007

In this paper, we have designed and implemented an optical signal processor in order to use in a fiber-optic current CT for electric equipments where its properties were discussed. The fabricated optical signal processor is used to reduce a measurement current error that induced by the effects of intensity variation in the optical output signal due to losses coming from optical components or polarization variation in a PFOCS. Also, the optical signal processor was fabricated in compact/lightweight with unification of opto-electronic transducer part, analog signal process part, and real-time measurement part consisted of a level shift and ${\mu}-processor$. The experiment of optical signal processor has been performed in the range of $0{\sim}7,500A$ using the PFOCS made all fiber-optic components. As a result of experiment, the linearity error of measurement current is less than 1.7% and its average error is less than 0.3% in the range of $1,000A{\sim}7,000A$.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.34 no.2
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• pp.126-129
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• 2021

We fabricated plate typed shunt resistors composed of carbon nanotube (CNT) and metal alloy for measuring DC current. CNT plates were prepared from dispersed CNT/Urethane solution by squeezing method. Cu/Ni alloys were prepared from composition-designed alloy wires for adjusting the temperature coefficient of resistance (TCR) by pressing them. As well, we fabricated a hybrid resistor by squeezing the CNT/Urethane solution on the metal alloy plate directly. In order to confirm the composition ratio of the Cu/Ni alloy, we used an energy-dispersed X-ray spectroscopy (EDX). Cross-section and surface morphology were analyzed by using a scanning electron microscopy (SEM). Finally, we measured the initial resistance of 2.35 Ω at 25℃ for the CNT paper resistor, 7.56 mΩ for the alloy resistor, and 7.38 mΩ for the hybrid resistor. The TCR was also measured to be -778.72 ppm/℃ at the temperature range between 25℃ to 125℃ for the CNT paper resistor, 824.06 ppm/℃ for the alloy resistor, and 17.61 ppm/℃ for the hybrid resistor. Some of the hybrid resistors showed a near-zero TCR of 1.38, -2.77, 2.66, and 5.49 ppm/℃, which might be the world best-value ever reported. Consequently, we could expect an error-free measurement of the DC current using this resistor.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.1
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• pp.305-325
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• 2014

In cloud computing infrastructure, current virtual machine trust measurement methods have many shortcomings in dynamism, security and concurrency. In this paper, we present a new method to measure the trust of virtual machine. Firstly, we propose "behavior trace" to describe the state of virtual machine. Behavior trace is a sequence of behaviors. The measurement of behavior trace is conducted on the basis of anticipated trusted behavior, which not only ensures security of the virtual machine during runtime stage but also reduces complexity of the trust measurement. Based on the behavior trace, we present a Dynamic Tree Style Trust Measurement Model (DTSTM). In this model, the measurement of system domain and user domain is separated, which enhances the extensibility, security and concurrency of the measurement. Finally, based on System Call Interceptor (SCI) and Virtual Machine Introspection (VMI) technology, we implement a DTSTM prototype system for virtual machine trust measurement. Experimental results demonstrate that the system can effectively verify the trust of virtual machine and requires a relatively low performance overhead.

• Transactions of the Korean Society of Automotive Engineers
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• v.25 no.2
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• pp.149-156
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• 2017

Various kinds of accessories(e.g., clock, radio, automatic door locks, alarm devices, etc.) or unit components (e.g., black box, navigation system, alarm, private audio, etc.) require dark current even when the vehicle power is turned off. However, accessories or unit components can be the causes of excessive dark current generation. It results in battery discharge and the vehicle's failure to start. Therefore, immediate detection of abnormal dark current and response are very important for a successful repair job. In this paper, we can increase the maintenance efficiency by presenting a standardized diagnostic process for the measurement of the dark current and the existing problem. As a result of the absence of a system to block the dark current in a vehicle, diagnosis and repair were performed immediately by using a standardized dark current diagnostic process.