• The Journal of the Korea institute of electronic communication sciences
• /
• v.18 no.4
• /
• pp.669-676
• /
• 2023

In this paper, a multi-purpose golf putting range finder based on an IR razer sensor and an inertial sensor was designed and made. It was designed to measure distance and slope within a 50m outdoor measurement range for the main purpose of golf putting distance measurement, and at the same time, it is designed to measure temperature information that affects putting. In addition, the distance meter supports house maintenance work by providing length and horizontality measurement values within the indoor 80m measurement range, and provides safety from indoor or vehicle fires by providing indoor temperature measurement values to mobile phones through linkage with the web server. In order to evaluate the accuracy of the proposed method and its interworking performance with a smartphone, a prototype was produced and a web server was built, and the usefulness was confirmed by showing an acceptable error rate within 5% in repeated experiments.

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

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.31 no.4
• /
• pp.261-266
• /
• 2018

When the clamp meter approaches the electric path where current is flowing, leakage current can be measured at a distance from the electric current because the induced current increases as the magnitude of the current increases and approaches nearer to the electric path. Therefore, measurements were carried out from a distance to avoid this effect. In addition, the measured values differ depending on the location of the power line that penetrates the ZCT of the clamp meter, thus measurements were performed at a location where this effect was minimized. The fraction of compliant branch circuits, whose leakage current was lower than 1.00 mA, was found to be 69.0% out of the total of 439 branch circuits, while the percentage of compliant branch circuits having an insulation resistance higher than $0.20M{\Omega}$ was found to be 93.2%. The reason why the percentage of compliant branch circuits with low leakage current was low might be due to the inclusion of capacitive leakage current in the total measured leakage current.

• Water for future
• /
• v.6 no.2
• /
• pp.30-37
• /
• 1973

The coefficient of the current meter generally determined by the maker Its coefficient is subject to being changed with time. Therefore the coefficient of the current meter has to be checked up before it is ready to be used Such an inspection is termed a current meter rating The current meter equipped an electronic apparatus and all the others are to be rated in a rating flume. The price current meter which is most widely used for measuring flow velocities ranging between 0.3m/sec and 3.5m/sec has been used in this study. The length of the flume and the optimum range of the rating in the cross section are determined in the range of 20∼120cm deep, 50∼160cm wide of the flume. In this study, the 23 different kinds of the current meter rating enabled us to determine the constants a and b of the following equation. V=an+b(m/sec) where, n is number of revolution per second(n=N/T) V is velocity(v=D/T) The above constant can be determined by the least squares method and plotting, using the velocity(V=D/T) and the number of revolution per second(n=N/T) obtained from the running distance(D), time(T), the number of revolutin(N), and the running number(m). From the experiments the following conclusions are drawn: 1) The rating flume is large enough if the flume is 110∼120cm deep, and 40∼50m long. 2) The optimum depth for rating of a current meter is in the range of h=40∼50cm.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.7 no.1
• /
• pp.37-48
• /
• 1989

Electronic Distance Meter(EDM) is widely used for the traverse surveying and trilateration net recently, therefore, the study on reliability of EDM is very important. In this study, the reliability of EDM is examined by calculating the distortion of traverse surveying net, statistically analyzing the results of side length between triangulation and trilateration. As the result of this study, correction equation of EDM and steel-tape is obtained. And also, linear regression equations with correlation coefficient (0.89-0.98) show resulting from the error analysis of each side length. In addition to checking the distortion of traverse surveying net, distortion calculated with correction EDM appears to be the smallest value.

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

• Journal of the Institute of Electronics and Information Engineers
• /
• v.51 no.8
• /
• pp.178-184
• /
• 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 the Korean Society of Industry Convergence
• /
• v.23 no.6_2
• /
• pp.971-977
• /
• 2020

In this paper, We propose a portable electrostatic meter which can measure high voltage static electricity caused by friction to prevent fire or explosion accidents in grinding, crushing, power injection, transport, filling, dust removal, painting, and foreign matter removal processes. The proposed device not only shows static electricity strength in 4 steps with respect to distance and voltage but also gives warning with a buzzer, on process facilities that are likely to generate high voltage static electricity due to friction. The device is implemented by filtering the signal detected by the wireless antenna, amplifying the signal by 6 times, and passing the signal through the integrator circuit. Tests are carried out with an electrostatic discharge simulator. And the results show that 4 LEDs are turned on at the distance of 10cm, 3 LEDs at 12cm, 2 LEDs at 13cm, and 1 LED at 15cm, when a fixed voltage of 500V is given. And also, the tests show that the static electricity can be detected at 5cm on 100V, 10cm on 200V, 15cm on 500V, 20cm on 1000V, and 25cm on 1500V. We expect to reduce accidents caused by static electricity by allowing safety managers on fields where fire or explosion accidents can happen to monitor static electricity.

• Journal of the Korean Institute of Intelligent Systems
• /
• v.24 no.4
• /
• pp.424-429
• /
• 2014

In this paper, an image-based luminance measurement system(LMS) is proposed to measure the luminance of outdoor signboards. We design the LMS that can improve disadvantages of efficiency of the point-luminance meter and portability of face-luminance meter using the image of DSLR camera and print out the luminance value by using the proposed luminance analysis algorithm in real time. Outdoor signboards have various size and shape, and are also installed on the various place. Luminance of the signboard is influenced by measurement location, angle, color, etc. Therefore, we measure the change of luminance value in accordance with measurement location for accurate luminance measurement and then consider the luminance value according to the measurement distance. We obtain a numerical relation between luminance value and measurement location. The proposed LMS is verified through comparative experiment with point-luminance meter.

• Journal of the Korean Institute of Intelligent Systems
• /
• v.26 no.4
• /
• pp.321-326
• /
• 2016

In this paper, we propose a luminance correction algorithm based on measuring position for potable luminance measurement system. Measurement position and angle have an affect on the luminance value. We improve the position-based luminance measurement system using luminance correction algorithm based on the measuring angle. We analyze change of luminance value according to the measurement distance and angle from camera and light source. The certified point-luminance meter is used to evaluate a scene luminance measuring method using the image information of camera. Also, we derive an expression equation for evaluating luminance value from determined position. The performances of the proposed system are verified by using comparative experiments with the point-luminance meter using experimental signboard.