• Journal of Biosystems Engineering
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• v.24 no.2
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• pp.123-134
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• 1999

The electrical properties such as dielectric constant, dielectric loss factor and AC conductivity of grain were presented to measure the moisture content of grain using RF impedance. At frequency ranging from 1 to 10MHz and room temperature, $20^{\circ}C$, vector network analyzer(HP4195) and coaxial type sample holder were used to analyze the electrical properties of paddy(11∼24%w.b.), brown rice(11∼18%w.b.), barley(11∼21%w.b.) and wheat(11∼23%w.b.) depending on the moisture content, frequency and bulk density. The dielectric constant and AC conductivity of grain samples increased with moisture content and bulk density. The dielectric constants decreased with frequency and could be expressed as function of the moisture density(decimal moisture $content{\times}bulk$ density).

• Journal of Environmental Science International
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• v.22 no.4
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• pp.415-424
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• 2013

In this paper, time series of soil moisture were measured for a steep forest hillslope to model and understand distinct hydrological behaviours along two different transects. The transfer function analysis was presented to characterize temporal response patterns of soil moisture for rainfall events. The rainfall is a main driver of soil moisture variation, and its stochastic characteristic was properly treated prior to the transfer function delineation between rainfall and soil moisture measurements. Using field measurements for two transects during the rainy season in 2007 obtained from the Bumrunsa hillslope located in the Sulmachun watershed, a systematic transfer functional modeling was performed to configure the relationships between rainfall and soil moisture responses. The analysis indicated the spatial variation pattern of hillslope hydrological processes, which can be explained by the relative contribution of vertical, lateral and return flows and the impact of transect topography.

• The Journal of the Society of Korean Medicine Diagnostics
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• v.14 no.2
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• pp.67-74
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• 2010

Objectives: Tongue moisture is one of major features in tongue diagnosis of Oriental Medicine. But with regard to the methods to qualify the tongue moisture level, there have been no adequate modalities to satisfy clinicians' needs. So we developed an novel device and method to quantify the tongue moisture level without contact. Methods and Materials: Ratio of saturated area to total tongue area in the image captured with a spot light at various angles was calculated. We regarded that ratio represented the moisture of tongue surface. To evaluate the performance of suggested method, we observed the correlation between conventional contact method and our method with 19 healthy subjects. Results: With comparison to conventional contact method (Schirmer test), the suggested method showed good correlation (R = 0.8602, R2 = 0.7399). Conclusion: This Method could be a convenient and robust method to evaluate tongue moisture.

• Journal of the Korean Wood Science and Technology
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• v.22 no.4
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• pp.37-42
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• 1994

The adsorption of water vapor and equilibrium moisture content(EMC) of the specimens for four softwood species dried by conventional- and high temperature method and equilibrated to 15% of the target EMC condition at 25$^{\circ}C$ were determined by oven drying method and with moisture meters. The amount of adsorption for high temperature dried red pine was significantly higher than that of conventional kiln dried wood, while those of eastern white pine, eastern hemlock and Norway spruce were not significantly different between drying methods. EMCs of these four species determined by oven drying method and with capacitive admittance moisture meter were not significantly different between drying methods. EMC of high temperature dried red pine determined with resistance moisture meter was significantly higher than that of conventional kiln dried wood. But EMCs of other species did not show significant difference between drying methods. EMCs of conventional and high-temperature dried wood determined with electronic moisture meters, especially in the case of the capacitive-admittance moisture meter measurement, were lower than that determined by oven drying method.

• The Journal of Korean Medicine
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• v.38 no.4
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• pp.55-61
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• 2017

Objectives: In order to accurately measure skin moisture and accumulate normal skin moisture data, analyzing the uncertainty of the skin moisture measurement and establishing standard reference data is essential. It helps to evaluate the skin's condition and has great significance in diagnosis and treatment. In this study, the traceability of the equipment and the uncertainty of the results were analyzed for their potential use in the field of Korean medicine. The data was collected measuring skin moisture on the sole of the foot. Methods: One professional measured the moisture of the adult male's foot 10 times following a determined protocol. The standard uncertainty of repeated measurements was calculated from the mean value of 10 repeated measurements. Ten trainee participants also measured the adult male's foot following a determined protocol. The standard uncertainty by tester was calculated from the value of repeated measurements. Results: As a result of analyzing the difference between the mean and standard uncertainties in both the expert and trainees, it was confirmed that the variance in this study did not satisfy the normal distribution. In addition, the Mann-Whitney U-test was carried out, and it was found that there was no significant difference in the measured values of the two groups. The authorized uncertainty of measurements and traceability of all the equipment was not confirmed. Conclusions: This paper establishes the basis for later measurement-equipment research to provide the objective indicators to approach the dryness of plantar skin from dehydration, the Korean medicine perspective.

• Journal of Korea Water Resources Association
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• v.32 no.3
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• pp.215-223
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• 1999

Recently, measurement of soil moisture contents using TDR (time domain reflectometry) has been proven to be viable technique. The first empirical model proposed by Topp et al. (1980) has been widely used to determine moisture contents of soils from the TDR-measured dielectric constants. However, applicability of the model was limited to medium-textured soils. In this study, we investigate the applicability of the model to sandy-gravelly soils. Calibration experiments consisted of measurement on travel time of electromagnetic waveform along the parallel TDR rods inserted into samples and gravimetric determination of soil moisture contents. The experiments are performed for two sets of samples different in the length and each set consisted of seven different particle size distributions with various gavel contents. The calibration results show that the Topp equation overestimated the measured moisture content for a given dielectric constant by 3 to 8%. We therefore propose new empirical relationships valid for sandy-gravelly soils.

• Journal of Biosystems Engineering
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• v.35 no.3
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• pp.175-181
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• 2010

This study compared moisture content measured by moisture meter of microwave resistance type(MMMRT) and standard moisture content of paddy, and developed the correction equation using linear and curvilinear regression analysis, and to explore its significance test. The correction factor according to the range of moisture content was developed to improve the measurement precision of MMMRT. The results were as followings. The coefficients of determination of correction equation by linear and curvilinear regression analysis with comparing the MMMRT and standard moisture content were 0.946 and 0.968, respectively. The moisture content error of MMMRT and standard moisture content measured after the MMMRT were corrected by moisture content rate of every 5% using the correction equation by curvilinear regression analysis appeared with 0~0.5% and 0.9~1.8% respectively in the moisture content range of 15~20% and 20~25%.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2000.11b
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• pp.188-195
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• 2000

This study was conducted to measure the moisture content of powdered food using RF impedance spectroscopic method. In frequency range of 1.0 to 30㎒, the impedance such as reactance and resistance of parallel plate type sample holder filled with wheat flour and red-pepper powder of which moisture content range were 5.93∼-17.07%w.b. and 10.87 ∼ 27.36%w.b., respectively, was characterized using by Q-meter (HP4342). The reactance was a better parameter than the resistance in estimating the moisture density defined as product of moisture content and bulk density which was used to eliminate the effect of bulk density on RF spectral data in this study. Multivariate data analyses such as principal component regression, partial least square regression and multiple linear regression were performed to develop one calibration model having moisture density and reactance spectral data as parameters for determination of moisture content of both wheat flour and red-pepper powder. The best regression model was one by the multiple linear regression model. Its performance for unknown data of powdered food was showed that the bias, standard error of prediction and determination coefficient are 0.179% moisture content, 1.679% moisture content and 0.8849, respectively.

• Journal of Biosystems Engineering
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• v.25 no.2
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• pp.97-106
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• 2000

To develop the grain moisture meter using microwave free space transmission technique, a 10.5GHz microwave signal with the power of 11mW generated by an oscillar with a dielectric resonator is transmitted to an isolator and radiated from a transmitting $2{\times}2$ microstrip patch array antenna into the sample holder filled with the 12 to 26%w.b. of Korean Hwawung paddy rice. the microwave signal, attenuated through the grain with moisture, is collected by a receiving $2{\times}2$ microstrip patch array antenna and detected using a Shottky diode with excellent high frequency characteristic. A pair of light and simple microstrip patch array antenna for measurement of grain moisture content is designed and implemented on atenflon substrate with trleative dielectric constant of 2.6 and thickness of 0.54 by using Ensemble ver. 4.02 software. The aperture of microstrip patch arrays is 41 mm width and 24mm high. The characteristics of microstrip patch antenna such as grain. return loss, and bandwidth are 11.35dBi, -38dB and 0.35GHz($50^{\circ}$ at far-field pattern of E and H plane. The width of the sample holder is large enough to cover the signal between the antennas temperature and bulk density respectively. The calibration model for measurement of grain moisture content is proposed to reduce the effects of fluectuations in bulk density and temperature which give serious errors for the measurements . From the results of regression analysis using the statistically analysis method, the moisture content of grain samples (MC(%)) is expressed in terms of the output voltage(v), temperature (t), and bulk density of samples(${\rho}b$)as follows ;$$MC(%)\;=\;(-3.9838{\times}10^{-8}{\times}v^{3}+8.023{\times}10^{-6}{\times}v^{2}-0.0011{\times}v-0.0004{\times}t+0.1706){\frac{1}{{\rho}b}}{\times}100$ Its determination coefficient, standard error of prediction(SEP) and bias were found to be 0.9855, 0.479%w.b. and -0.0.369 %w.b. respectively between measured and predicted moisture contents of the grain samples.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.31 no.3
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• pp.105-109
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• 1999

The purpose of this experiment was to see the effect of local basis weight on the local strain during changing moisture content in handsheets. The averaged strain value of the whole size of paper sheet did not give more valuable information to explain non uniform deformation in the paper sheet. The combination of intact strain measurement system KISA (Linear Image Strain Analysis) and local basis weight measurement method using a scanner made it possible to compare local basis weight with local strain to explain moisture induced paper deformation . Usually higher basis weight local area showed higher moisture induced local strain. However, the hygro-induced strain values were highly affected by the behavior of neighbor local areas. Well distributed local basis weight paper would give more uniform local strains than those of non-uniformed local basis weight paper.