• Journal of Korea Soil Environment Society
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• v.3 no.1
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• pp.83-92
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• 1998

This study presents a relationship between gas quantity and measurement resistance using the bubble meter, the water head indicator and the rotor meter from the gas vent sanitary landfill. From the one-dimensional analyses and experiments, the below results have been obtained. The gas volume sourcing from the gas vent depends on the permeability of final cover soil, its cover depth and distance between the gas vents. The total gas volume producing in the interested domain may be accurately measured by the bubble meter, the water head indicator and the rotor meter if the clay is used for the final cover soil. The required times approaching to the steady-state are different with respect to the flow meters, one day is for the bubble meter and the water head indicator and one hour for the rotor meter.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.23 no.5
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• pp.9-17
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• 2009

In this paper, we describe a flow meter system for pulverized coal developed for the pulverizer-burner system of a boiler or blast furnace, which uses the density and the velocity of the granule flow. The granule flow density is measured by a sensor that detects the capacitance from the electrode on the surface of the piping system. The velocity of granule flow can be calculated using the distance between two pairs of built-in sensors in the flow direction, the time obtained from the sampling cycle using the correlation method between two waveforms of the sensors. The flow rate is calculated from the density and velocity of the granule flow. The reliability and accuracy of the flow meter system has been verified by comparing the data with the weight measured from a load-cell.

• Magazine of the Korean Society of Agricultural Engineers
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• v.17 no.3
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• pp.3872-3877
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• 1975

This study was conducted to examine the effects of the change of cap hole diameter and pressure on the travelling distance and the sprayed particle size for the medium range nozzle. The results of this study are summarized as follows; 1) The effective travelling distance was about from 1 meter to 8 meters and centro-position of the travelling distance was about 3 or 5 meters. 2) Main effect of change of cap hole diameter for the travelling distance was a slight convex quadratic curve. 3) Main effect of change of pressure increased linearly, its increasing rate about 1.6 was large. 4) Sizes of sprayed particles were less than 250${\mu}$ generally and the sizes decreased according to the increasing of travelling distance. 5) Changes of diameter of sprayed particles by cap hole diameter increased in accordance with increasing of cap hole diameter. 6) Changes of diameter of sprayed particles by the groove depth of swirl plate was very slight.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.14 no.11
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• pp.1123-1128
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• 2004

An experimental study on firing noise of K2 rifle was performed. Firing noises of K2 rifle were measured at close distance to rifle. Firing noise of K2 rifle which made in Korea, has not measured before. The measurement of firing noise at close distance is not simple, because the amplitude of firing noise is much bigger than the measuring limit of ordinary sound level meter even though it uses a signal attenuator. The measurement of firing noise at close distance is necessary for noise source positioning and for obtaining the sound power of K2 rifle. By this experimental study, the firing noise levels of K2 rifle at different positions are obtained and these data can be used to Predict the sound pressure level at any distance from muzzle of the rifle. Also these data can be used to calculate the threshold shift of gunner's ear.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.8 no.1
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• pp.51-56
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• 1990

Recently, Electronic Distance Meter(EDM) is widely used for the traverse surveying and trilateration net. In this study, the closed traverse network is precisely adjusted by simultaneous adjustment of the observed angle and distance, using the Electronic Total Stations (Set 3). And also, it is examined that each kind accidental errors appear observed angles according to the observed distance and the number of repeating angle. In addition to the result, of checking between the simultaneous adjustment, the compass rule and transit rule, simultaneous adjustment in combination of the observed angle and distance is more accurate and effective than other adjustment.

• The Journal of the Petrological Society of Korea
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• v.22 no.1
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• pp.71-81
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• 2013

Measuring the distance between benchmarks placed on a volcano tens to thousands of meters apart can sometimes pinpoint where and when magma is rising toward the surface. Rising magma will sometimes push overlying rocks upward or shove them aside. In either case, one part of the volcano may actually move horizontally relative to another part from as little as a few millimeters to as much as several tens of meters. The challenge in measuring such changes with an electronic distance meter is putting benchmarks in the right places and making frequent measurements between pairs of benchmarks. An electronic distance meter is an instrument that both sends and receives an electromagnetic signal. Depending on the distance between the EDM and reflector, the wavelength of the returned signal will be out of phase with the transmitted signal. The instrument compares the phase of the transmitted and received signals and measures the phase difference electronically. There is a wide range of EDM capabilities in range and precision, but for volcano monitoring purposes, short-range (less than 10 km) to medium-range (less than 50 km) EDM's are typically used. Short-range EDM's transmit and receive the near visible infrared part of the electromagnetic spectrum for measuring distances with an accuracy of about 5 mm.

• Physical Therapy Korea
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• v.24 no.3
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• pp.1-9
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• 2017

Background: The method of measuring the walking function of patients with chronic stroke differs depending on patients walking capability and environmental conditions. Objects: This study aimed to demonstrate the influences of walking capacity and environmental conditions on the results of short- and long-distance walk tests in patients with chronic stroke. Methods: Forty patients with chronic stroke volunteered for this study, and allocated to group-1 (<.4m/s, household walking, $n_1=13$), group-2 (.4~.8m/s, limited community ambulation, $n_2=16$), and group-3 (>.8m/s, community ambulation, $n_3=11$) according to their walking capacity. The 10-meter walk test (10MWT) and 6-min walk tests, (6MWT) were used to compare the short- and long-distance walk tests results, which were randomly performed under indoor and outdoor environmental conditions. Results: The comparison of the results obtained under the indoor and outdoor conditions revealed statistically significant differences between the groups in the 6MWT and 10MWT (p<.05). Post-hoc tests' results showed significant differences between groups-1 and -2 and between groups-1 and -3 in the 10MWT, and between group-1 and -3 in the 6MWT. Furthermore, in group-2 the 10MWT and 6MWT results significantly differed between the indoor and outdoor conditions, and the values measured under the indoor and outdoor conditions significantly differed between 10MWT and 6MWT (p<.05). Group-3 showed a significant difference in 10MWT results between the indoor and outdoor conditions (p<.05). Conclusion: These findings suggest that the results of the short- and long-distance walk tests may differ depending on the walking capacity of patients with chronic stroke and the environmental condition under which the measurement is made, and these effects were greatest for the patients with the limited community ambulation capacity.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.12
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• pp.2227-2232
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• 2007

In this paper, it is presented a Real FFT for the FMCW radar distance measurement with high resolution. The high distance resolution needs the measurement of the accurate beat frequency. To improve the distance resolution, zoom fft, decimation, digital low pass filter and zero padding method are used. The simulation results using the Matlab show ${\pm}5mm$ of distance resolution and the measuring range is up to 35meter.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.8
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• pp.178-184
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• 2014

In this study, we develop liquid density sensor by measuring of balanced position between gravity and bouyancy, corresponding to liquid density, using distance measuring by magnetostriction technology. For improvement of accuracy of liquid density sensor system. And we derive the related equation between liquid density and moving distance of density sensor, and make the calibration method for liquid density sensor by magnetostriction technology. Using fabricated liquid density sensing system and derived equation, have measured the density of several liquids. And compare it to measuring results using Oscillating U-tube type high accuracy density meter, having 0.000001 g/cc resolution. The deviation of results between two density measuring systems was less than 0.001 g/cc.

• Journal of Bio-Environment Control
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• v.5 no.2
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• pp.167-173
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• 1996

Laser distance meter and x-y robot employed in the extraction of three dimensional image recognition of muskmelon net and recognized the characteristics of that. All data measured transmitted to the PC/AT in the computer room and programmed with Visual Basic(Microsoft). Alteration of the concentration and application time of nutrient solution modified the net height and width of hydroponically grown muskmelon. Net height and width which are the characteristics of muskmelon depended on the concentration of nutrient solution used. Decreasing with the concentration of nutrient solution lowered the occupying ratio of net and also observed the tendency of widening of muskmelon net.