• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.2 no.2
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• pp.137-141
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• 1990

When the relative humidity is measured with an aspirated psychrometer, three factors, which affect the measurement of relative humidity, are atmospheric pressure, the size of wet element and the wind velocity. This paper investigated the effects of the above three factors, and the computer code was developed in order to enhance the accuracy of the relative humidity measurement. As results, it is found that the relative humidity decreases by 6%RH with increasing atmospheric pressure from 650 mbar to 1100 mbar. It is found that the relative humidity drops down when the size of the wet element increases, though the effect of the size of the wet element is not significant. Finally, relative humidity increases with the increasing wind velocity. The difference between the psychrometic table in the present KS and the present results is about 2%RH maximum. As a conclusion, the three factors mentioned above should be considered in order to secure accurate measurement of relative humidity.

• 유체기계공업학회:학술대회논문집
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• 1999.12a
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• pp.189-199
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• 1999

The revision was proposed for methods A-weighted sound pressure measurement for fans, blowers and compressors in order to apply newly developed measurement techniques to KS B 6361 established in 1987. This proposal includes modification of terminologies, revision of sound power methods for radiated sound from the body, inclusion of In-duct measurement method, and correction method for flow noise upon microphon.

• Journal of Drive and Control
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• v.10 no.4
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• pp.29-33
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• 2013

Pneumatic system is widely applied in various industry because it have a many advantage(low cost, high safety, etc..). For design of pneumatic system, accurate flow measurement is required. In this study, compressible fluid flow measurement apparatus was designed and built. It uses an isothermal chamber that can approximate isothermal condition. Therefore, it can be measured for flow-rate using pressure response of isothermal chamber. As a result, this apparatus can be measured for sonic conductance and critical pressure ratio of pneumatic components and it required less time and energy than conventional flow meter. The effectiveness of the designed apparatus is proved by experimental result.

• IE interfaces
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• v.15 no.4
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• pp.432-438
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• 2002

When the trailing edge and leading edge of an airfoil contour of high pressure compressor blades are measured, there exists a measurement error due to the size of the probe stylus ball diameter. In the paper an experimental study is provided to determine the optimum diameter of the probe stylus in inspecting the airfoil of the high pressure compressor blade. The measurement and analysis procedure suggested in this paper will be helpful to those who are involved in measuring and inspecting various types of blades.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.17 no.4 s.121
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• pp.333-341
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• 2007

Waveform design method for inkjet printing has been proposed tv pressure wave measurement. The pressure wane inside the inkjet dispenser can be effectively measured by current measurement due to self-sensing capability of PZT. The pressure wave measured from current was verified by commercially availablelaser vibrometer. In order to obtain high speed inkjet droplets, two pulse waveform was designed such that the pressure wane after droplet formation can be minimized.

• Journal of Ocean Engineering and Technology
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• v.34 no.6
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• pp.419-427
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• 2020

In this study, a particle image velocimetry (PIV)-based pressure estimation method was investigated, with application to the wave-in-deck loading phenomenon. An experimental study was performed in a two-dimensional wave tank using a fixed deck structure under a focused wave, obtaining local pressures by pressure sensors, global loads by load cells, and instantaneous velocity fields using the PIV measurement technique. The PIV-based pressure estimation method was applied using the Euler equation as the governing equation, and the proper time step for the wave impact pressure was studied using the normalized root-mean-square deviation. The pressure estimation method showed good agreement for the local impact pressure in comparison with the measured pressure by the pressure sensors. However, some differences were observed in the peak pressure due to the limitations of the Euler equation and the sampling rate of the measurement system. Using the estimation method, the pressure fields during wave-in-deck loading were determined in the study, with an analysis of the mechanism of impact and negative pressure occurrence.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.18 no.4
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• pp.161-168
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• 2018

High blood pressure is main today's adult disease and existing blood pressure gauge is not possible for real-time blood pressure measurement and remote monitoring. But real-time blood pressure monitoring u-healthcare system makes effect health management. In my paper, for monitoring real-time blood pressure, an architecture of real-time blood pressure monitoring system which consisted of wrist type-blood pressure measurement, smart-phone and u-healthcare server is presented. And the analog circuit architecture which is major core function for pulse wave detection and digital hardware architecture for wrist type-blood pressure measurement is presented. Also for software development to operate this hardware system, UML analysis method and flowcharts and screen design for this software design are showed. Therefore such design method in my paper is expected to be useful for real-time blood pressure monitoring u-healthcare system implementation.

• Proceedings of the Korean Geotechical Society Conference
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• 2001.03a
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• pp.223-230
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• 2001

Nine different types of the reinforced railroad roadbeds which . are located in between Suwon-Chunan station of Kyongbu line were constructed in order to increase the bearing capacity of railroad roadbed and to improve the ridability as a part of speed-up project of conventional railroad systems. Each three sections were composed of weathered granite soil, crushed stone and furnace slag(HMS25), and fully instrumented with earth pressure cells, settlement plates and geophones to monitor the behavior of roadbeds under actual train loads. Field measurement has continued since October 31, 2000 and presently with rather longer measurement interval. The measurement data such as settlement, earth pressure and vibration levels are currently under analysis process. In this paper, only cumulative measurement data of railroad roadbeds were introduced. In the near future, comprehensive measurement data and result of analysis will be presented and design technique for the reinforced railroad roadbed will be proposed as a final product of this study.

• Journal of the Korea Institute of Military Science and Technology
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• v.19 no.3
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• pp.339-345
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• 2016

This paper is concerned with the numerical simulation result of pressure propagation to the main charge by warhead penetration into concrete targets. In this study, we developed on-line pressure measurement method in the main charge during warhead penetration. Using the on-line pressure measurement method, we successfully recorded the pressure-time history in the main charge during the field penetration test. Then we compared result of numerical simulations with test data and found that the simulation results are in good agreement with the test results. Finally, through the numerical calculations it is concluded that the installation of liner is effective in reducing pressure level produced in the main charge.

• Journal of the Korean Society of Clothing and Textiles
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• v.46 no.5
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• pp.827-835
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• 2022

Clothing pressure is considered the essential factor affecting the comfort of clothing, so it is crucial that it is measured precisely. The purpose of this study is to construct a prototype using the Adafruit Flora as the Arduino system, which can be used as a wearable framework for easy, low-cost, and precise clothing pressure measurement. The study also aims to determine how best to conduct the procedure of sensor calibration. To optimize the accuracy of the sensors, the calibration procedure was implemented using mathematical methods that combined polynomial and exponential regression in a hybrid approach. The prototype can easily measure clothing pressure even during active movements, as seen in the detection of stable signals. In addition, since the system was specifically proposed as a wearable patch that can be easily attached and removed as necessary, it can also be used to standardize the value of clothing pressure in each movement.