• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.2068-2069
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• 2007

This study describes a compairison leakage current properties between a polluted insulator and insulator subjected to salt polluted condition. Exposure tests at a sea coast test and the leakage current of insulators, climate conditions, and salt deposit density were measured during the tests. Appearance of leakage current for the insulator was affected by the humidity and the salt deposition on the surface. comparison of leakage current under salt polluted conditions. salt polluted test and humidity tests were carried out in laboratory using the same insulator profiles in oder to determine the leakage current patterns during critical conditions

• The Journal of Internal Korean Medicine
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• v.30 no.1
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• pp.200-211
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• 2009

There are many reports about correlations between meteorological elements and stroke. In Oriental medicine, it is recognized that the weather affects the human body and diseases, but there are few studies about the correlation between meteorological elements and pattern identification of stroke. 105 stroke patients classified into fire-heat pattern or dampress-phlegm pattern were registered during the study period. We took the measurement of each meteorological element (atmospheric pressure, temperature, humidity, wind speed) according to pattern identification and analyzed pattern identification into two groups according to mean of each meteorological element during the study period. Mean temperature was higher with the heat-fire pattern than with the dampness-phlegm pattern. Heat-fire pattern also had higher frequency when temperature was higher than mean temperature. There was no correlation between atmospheric pressure, relative humidity, or wind speed and pattern identification.

• Journal of Advanced Navigation Technology
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• v.16 no.5
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• pp.839-845
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• 2012

This paper deals with the design and development of the remote control and measurement systems by Embedded Web Server. The remote control and measurement systems are implemented by Cortex M-3 ARM micro-controller. The user application software for the control and measurement system user, and the firmware software of device drivers for peripherals such as a digital input/output device, AD/DAC(Analog to Digital/Digital to Analog Converter), LCD, and temperature/humidity sensor are developed in Eclipse environment using Codesourcery C, Java script, and HTML. The experimental result of the proposed control and measurement systems implemented in this paper is evaluated via real-time experiments, which works well as designed.

• Particle and aerosol research
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• v.6 no.3
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• pp.123-129
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• 2010

As the indoor activity increases in recent years, the indoor air quality becomes more important. One of the major contaminants in office space is the copy machines and the laser based printers. These devices usually emit nano-particles and chemical species that may give some health effect. The amount of particles generated by the printers and copy machines depend on printer models, printing speed, toners, papers, humidity and so on. To evaluate the emission rate of nano-particles from Laser Printers, the mass concentration measurement method has been used (BAM, 2004). However, the mass concentration measurement method for nano-particles is tedious and time consuming. Therefore, for the development of a new nano-particle counting method, the nano-particle emission characteristics and size distributions are evaluated.

• Proceedings of the KIEE Conference
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• 2006.07d
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• pp.1783-1784
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• 2006

A laser interferometer is the unique measurement device that can measure the range up to a few meters with sub-nano resolution and this characteristic makes it as the important sensing device for the emerging nano-mechatronics technologies. The laser interferometer, however, is very sensitive to the environments such as temperature, humidity, sound noises, vibrations and air turbulences and these factors result in a few hundred nano meter errors. There have been many efforts to reduce these environmental errors. The output of the laser interferometer is assumed to be the sum of a real displacement and a Markov process noise. The purpose of this paper is to develop Kalman filter algorithms to reduce the laser interferometer measurement errors by exploiting the information of displacements in position-servo systems.

• Proceedings of the KIEE Conference
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• 2001.07c
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• pp.1472-1474
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• 2001

In this paper, a method was presented to estimate the contamination degree of outdoor insulator by the measurement of surface leakage current. Contamination is one of the most important factor to determine the performance of insulator. Thus, it is very important to exam the contamination degree on the outdoor insulator. There are many limits, such as reliability of data, interval of measurement and similarity of environmental conditions, in conventional method. So, the estimation technique for contamination has been needed to monitor the accurate pollution degree of insulator in situ. In this investigation, phase difference was measured to compare the variance of phase difference with the contamination degree and relative humidity. From the result, we could confirm the capability of the estimation method.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.517-520
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• 2003

The snow-fatting measurement system including the snow sensor applying the photo-coupler is investigated in this study and using this snow sensor the height of snow fallen is measured. To measure the snow depth, five photo sensors are arranged with 5 mm distance. The snow-falling measurement system, which is measuring the motor revolution controlled with stepping motor, is mounted above the snow surface. From this work, it is feasible to measure quantitatively the snow on real time. Its software implements a proven method to achieve valid measurements also under difficult conditions as future study. In cases where the snow sensor is applieded to the prediction of snow in the meteorological observation system and the snow removing system, it is recommend the GRS-Option in order to improve the quality of snow measurements for better compensation.

• Proceedings of the KIEE Conference
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• 2006.04a
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• pp.345-347
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• 2006

An interferometer is the unique measurement device that can measure the range up to a few meters with sub-nano accuracy and this characteristic makes it as the important sensing device for the emerging nano-mechatronics technologies. The interferometer, however, is very sensitive to the environments such as temperature, humidity, sound noises, vibrations and air turbulences and these factors result in a few hundred nano meter errors. There have been many efforts to reduce these environmental errors. These efforts are mainly focused in reducing the errors inside the interferometer and improving the environments physically. The purpose of this paper is to improve accuracy of the interferometer by using measurement noise models and the Kalman filter algorithm.

• The Journal of the Acoustical Society of Korea
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• v.31 no.4
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• pp.253-259
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• 2012

Goldingham's measurement of the velocity of sound undertaken in the early nineteenth century was the first large-scale measuring enterprise which considered various meteorological factors such as temperature, humidity, atmospheric pressure, the direction of the wind, etc. Goldingham's successful performance of measuring the velocity of sound by employing the sounds of cannons as sound source in Madras (now Chennai), a colonial region of India, for one and a half years was supported by material, institutional and social resources. As the official astronomer at the Madras Observatory, he was benefitted by the undemanding employment of accurate measuring instruments under the support of the Madras Army enabled him to gain reliable data and his reputation as professional experimentalist facilitated the acknowledgment of their trustworthiness.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.4A
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• pp.385-393
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• 2009

This study grasped the relationship between relative humidity in concrete and concrete shrinkage followed by pre-absorbed water of porous lightweight aggregates through measurements of concrete shrinkage and humidity and comparisons with established research results. It was showed that shrinkage reduction effect of lightweight concrete is 36% at 7 days early ages and 25% at 180 days long-term ages when water-binder ratio is 0.3. It also showed that shrinkage reduction effect is 19% at 7 days and 16% at 180 days when water-binder ratio is 0.4 and 37%, 32% when water-binder ratio is 0.5. The moisture supply effect of lightweight aggregates was remarkable at early age within 7~10 days irrespective of water-binder ratio. In case of waterbinder ratio is 0.3, the relationship between shrinkage and internal humidity of concrete has been underestimated regardless of applied existing model type and in case of water-binder ratio is 0.4, 0.5, measurement values are relatively similar with existing model equations. Finally this study did regression analyses about the relation among the humidity change and the shrinkage strain as a high-degree polynomial and derived parameters that can connect moisture movement analysis with differential shrinkage analysis in case of considering relative humidity at the time by moisture movement analysis of concrete.