• Journal of the Optical Society of Korea
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• v.19 no.4
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• pp.415-420
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• 2015

A novel method to measure the scale factor for the all-optical atomic spin inertial measurement device (ASIMD) is demonstrated in this paper. The method can realize the calibration of the scale factor by a self-consistent method with small errors in the quiescent state. At first, the matured IMU (inertial measurement unit) device was fixed on an optical platform together with the ASIMD, and it has been used to calibrate the scale factor for the ASIMD. The results show that there were some errors causing the inaccuracy of the experiment. By the comparative analysis of theory and experiment, the ASIMD was unable to keep pace with the IMU. Considering the characteristics of the ASIMD, the mismatch between the driven frequency of the optical platform and the bandwidth of the ASIMD was the major reason. An all-optical atomic spin magnetometer was set up at first. The sensitivity of the magnetometer is ultra-high, and it can be used to detect the magnetization of spin-polarized noble gas. The gyromagnetic ratio of the noble gas is a physical constant, and it has already been measured accurately. So a novel calibration method for scale factor based on the gyromagnetic ratio has been presented. The relevant theoretical analysis and experiments have been implemented. The results showed that the scale factor of the device was $7.272V/^{\circ}/s$ by multi-group experiments with the maximum error value 0.49%.

• Journal of the Korea Safety Management & Science
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• v.10 no.2
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• pp.217-223
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• 2008

Measurement is used for evaluation of product or process exactly. If it couldn't measured correctly, Quality-cost must be raised and it would be hard to improve product quality. So, this study suggests improvement guide line for the multilateral problems of measuring instrument operation based on the investigation of 157 small and medium-sized enterprises in February, 2008. To use inspection gig correctly, man who treat it must be accustomed with the structure, the performance, the method. The inspection gig is selected properly for the measurement goal. If not, results couldn't be correctly or wasted time, efforts, and costs. When selecting a inspection gig, the locating, the clamping, and the efficiency must be considered.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2003.10a
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• pp.311-314
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• 2003

This paper describes a virtual instrument system with faulty sensor reconstruction mechanism based on personal computer. This system consists of sensor control board using 16bit RISC machine, error signal reconstruction algorithm based on principal component analysis and auto tunned GUI interface according to the attached sensors. USB module is used for fast communication between PC and sensor controller. To show the veridity of the proposed system, the proposed system was applied to the developed sun tracker with 8 solar sensors.

• Current Optics and Photonics
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• v.2 no.6
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• pp.519-524
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• 2018

We propose a transverse load sensor with reconfigurable measurement accuracy based on a microwave photonic filter in the $K_u$ band, incorporating a polarization-maintaining fiber Bragg grating. A prototype sensor with a reconfigurable measurement accuracy tuning range from 6.09 to 9.56 GHz/(N/mm), and corresponding minimal detectable load range from 0.0167 to 0.0263 N/mm, is experimentally demonstrated. The results illustrate that up to 40% manufacturing error in the grating length can be dynamically calibrated to the same corresponding measurement accuracy for the proposed transverse load sensor, by controlling the semiconductor optical amplifier's injection current in the range of 154 to 419 mA.

• Current Optics and Photonics
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• v.4 no.1
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• pp.1-8
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• 2020

We research a system of compressed-sensing computational ghost imaging (CSCGI) based on the intensity fluctuation brought by turbulence. In this system, we used the gamma-gamma intensity-fluctuation model, which is commonly used in transmission systems, to simulate the CSCGI system. By setting proper values of the parameters such as transmission distance, refractive-index structure parameter, and sampling rates, the peak signal-to-noise ratio (PSNR) performance and bit-error rate (BER) performance are obtained to evaluate the imaging quality, which provides a theoretical model to further research the ghost-imaging algorithm.

• Journal of Biosystems Engineering
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• v.35 no.6
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• pp.443-449
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• 2010

A machine vision-based instrument to measure a droplet size spectrum of a spray nozzle was developed and tested to evaluate its accuracy on measuring spray droplet sizes and classifying nozzle sizes. The instrument consisted of a machine vision, light emitting diode (LED) illumination and a desktop computer. The illumination and machine vision were controlled by the computer through a C++ program. The program controlled the machine vision to capture droplet images under controlled illumination, and processed the droplet images to characterize the droplet size distribution of a spray nozzle. An image processing algorithm was developed to improve the accuracy of the system by eliminating random noise and out-of-focus droplets in droplet images while measuring droplet sizes. The instrument measured sizes of the three different balls (254.0, 497.8 and $793.8\;{\mu}m$) and the measurement ranges were $241.2-273.6\;{\mu}m$, $492.9-529.6\;{\mu}m$ and $800.8-824.1\;{\mu}m$ for 254.0-, 497.84- and $793.75-\;{\mu}m$ balls, respectively. Error of the measured droplet mean was less than 3.0 %. Droplet statistics, $D_{V0.1}$, $D_{V0.5}$ and $D_{V0.9}$, of a reference nozzle set were measured, and droplet size spectra of five spray nozzles covering from very fine to extremely coarse were measured to classify spray nozzle sizes. Ninety percent of the classification results of the instrument agreed with manufacturer's classification. A comparison study was carried out between developed and commercial instruments, and measurement results of the developed instrument were within 20 % of commercial instrument results.

• Journal of radiological science and technology
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• v.25 no.2
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• pp.71-75
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• 2002

According to this study, we can make the radiation check meter which have not supply because of high cost and import barrier and lengthen its life by means of repairing of radiation bomb and equipment. We can make better medical service. In my study, I used the photodiod, photoelectron, among semiconductor detectors which have a excellent detect capacity and are low cost and small size. I set up this equipment in June 1, 2002, used 640 mA remote operative fluorography equipment, which make the grade as capacity test. I used the standard measuring instrument which took proofs from a agency, now it was using in measuring agency. The comparative measuring instrument used in same condition. I took the standard which was gauged with a connecting measuring instrument. Using a existing unconnected measuring instrument, I compared the accuracy with new unconnected one. As a result, three score are within the standard. For the detailed analysis, I took the average of percentage average error. So standard instrument was -0.02, comparable was -0.22, and new one was -0.17. New one took a closer measured value with standard than comparable one. In more study, I think to take more accurate value. I expect that my study will be a base of measuring instrument, with low cost, supply of this instrument increase, I expect to decrease radiation bomb and maintain, repair and manager better.

• Journal of electromagnetic engineering and science
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• v.1 no.2
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• pp.139-145
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• 2001

In this paper, a coaxial sample holder is proposed with its de-embedding and parameter extraction procedure. The S-parameters were measured up to 1 GHz using network analyzer, HP8753D, and N-type connector together with the de-embedding of N-type connector. The proposed de-embedding procedure is performed to extract electrical parameters of blood glucose, which gives the permittivity of blood glucose. We also analyzed the error of extracted parameters, which are caused by instrument error and geometrical error. Using these error analyses, we reduced the error factors of extracted parameters. We extracted electrical parameters of glucose samples through these all extraction procedure and confirmed the possibility of glucose diagnosis system based on microwave system.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.12
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• pp.2296-2302
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• 2006

In this paper, we propose a development technique of high precision laser finder ranger within instrument distance 1km, instrument error less than 1 m by using pulse time of flight method in the 5m unit instrument and heterodyne method in the within Am unit. These propose methods can be more advanced to measurement velocity and more highly precision distance instrument not affected the strength of light. We also validate this usefulness.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.16 no.3
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• pp.69-75
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• 2017

There are two types of expensive measuring instruments currently on the market shape measurement and roundness measurement instruments. As they are very expensive, from tens of millions to more than 200 million won, buying them is economically burdensome for small companies or individuals. Therefore, in order to integrate the shape and roundness measurements into a single transfer device, this study aimed to reduce the trial and error by 3D modeling and simulation, and we confirmed the feasibility of operation. Based on these outcomes, a prototype hybrid measuring instrument was fabricated. As a result of performance evaluation and comparative evaluation, we verified the feasibility of implementation and application of the hybrid measuring instrument.