• Journal of the Korean Society for Precision Engineering
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• v.32 no.12
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• pp.1039-1047
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• 2015

Contact type sensors (e.g., displacement sensor and strain gauge) were typically used to evaluate the safety and mechanical properties in machines and construction. However, those contact type sensors have been constrained because of measurement problems such as surface roughness, temperature, humidity, and shape. The Digital Image Correlation (DIC) measurement system is a vision measurement system. This measurement system uses the taken image using a CCD camera and calculates the image correlation between the reference image and the deformed image under external force to measure the displacement and strain rates. In this paper, we discuss methods to improve the measurement precision of the digital image correlation measurement system. A tensile test was conducted to compare the precision improvement effects, by using the universal test machine and the DIC measurement system, with the use of subpixel algorithms, i.e., the Coarse Fine Search (CFS) algorithm and the Peak Finding (PF) algorithm.

• 한국가시화정보학회:학술대회논문집
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• 2001.12a
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• pp.62-74
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• 2001

Present paper describes the principles of PIV measurement approaching from the analytical view, which enables to explain the general form of principles covering all the PIV measurement, and that gives theoretical basis for its higher measurement performances. The explanation of the measurement principles started from the definition of governing equation in differential form as same as the gradient method, and the integral along the particle path line was executed to show the principle of the correlation method with same basis. The integral processes clearly shows the analytical reason why the correlation peak gives the terminal point of path line, and how the effects of deformation and rotation of fluid appears in the correlation map. These results have no differences from our experiences and understandings of the conventional PIV measurement definition in final form. However, the analytical approach enable to understand those facts a priori, and it makes easy to achieve the innovative higher performances of measurement. Analytical explanation clearly shows the behavior of the residual errors caused by the fluid motion, and it enables to analyze the measurement uncertainty theoretically.

• ETRI Journal
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• v.34 no.6
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• pp.858-868
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• 2012

In this paper, stochastic models for the cross-correlation of multiple channels are established based on measurement data collected using a wideband multiple-input multiple-output relay Band Exploration and Channel Sounder system at 3.7 GHz. We propose models for the cross-correlation characteristics of large-scale parameters (LSPs) between two links, that is, the base station and mobile station (MS) link and the relay station and MS link. The LSPs include shadow fading, Rician K-factor, delay spread, angle spread of arrival, and angle spread of departure. Furthermore, models are established for the cross-correlation of the small-scale fading in the impulse responses of two links. The statistics of these model parameters are investigated as functions of geometrical features of the multilink. They are extracted from a large amount of cross-correlation observations, which are obtained in three measurement sites along more than one hundred measurement routes. These models can be used together with the standard single-link channel models for the generation of correlated components, for example, path clusters, in two separate channels.

• Journal of Sasang Constitutional Medicine
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• v.7 no.2
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• pp.59-88
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• 1995

Three groups have participated in this study. 1) The first group consists of 57 patients were who had been treated in the Oriental Medical Hospital at Kyung Hee Medical Center. 2) The second group consists of 37 outpatients who had been treated in the Oriental Medical Hospital at Kyung Hee Medical Center. 3) The third group consists of 76 students of the Oriental Medical School at Kyung Hee University. The following conclusions were made in comparison with EAV measurement values, SaSang Constitution Classfication and CVA. 1. The following conclusions were made in comparison with EAV measurement values and Type(SaSang Constitution Classfication). 1) The analsis of the Correlation in Normal group with EAV measurement values and Type(SaSang Constitution Classfication). 2) The analysis of the correlation in patient group with EAV measurement values showed significant differences in Right meridians(Nerval degeneration vessel, Circulation, Allergy) and in Left meridian(Liver). 3) The analysis of the correlation in Total(Normal+patient)group with EAV measurement values showed significant differences in Right meridians(Large intestine, Nerval degeneration vessel, Circulation, Allergy, Pancreas) and in Left meridians(Lymph vessel, Nerval degeneration vessel, Spleen, liver). 4) The above results showed common-significant differences in Right Allery meridian and in Left Liver meridian. 2. The analysis of the correlation in EAV measurement values and Group (Cerebrovascular accident) showed significant differences in Right meridians(Lymph vessel, Lung, Nerval degeneration vessel, Allergy, Paren & Epith. degeneration vessel, Triple warmer, Heart, Pancreas, Stomach, Fibroid degeneration vessel, Skin, Fatty degeneration vessel, Heart, Stomach, Fibroid degeneration vessel, Skin, Fatty degeneration vessel, Bile duct, Kidney). 3. The analysis of the correlation in EAV measurement values and Para(GROUPS according to PARALYSIS)showed significant differences in Left Stomatch meridian. The analysis of the correlation in EAV measurement values and Para(GROUPS according to PARALYSIS) about the differance of right measurement values and left measurement values showed significant differences in Nerval degeneration vessel, Stomatch, Gall bladder & Bile duct, Kidney and Urinary Bladder meridians. 4. The analysis of the correlation in EAV measurement values and Compl(GROUPS according to COMPLICATION with CVA)showed significant differences in Right meridians(Lymph vessel, Articular degeneration vessel, Fatty degeneration vessel) and in Left meridians(Lung, Stomatch, Fatty degeneration vessel). 5. The analysis of the correlation in Type and MORPHOROGICAL DIAGRAMING (HTOUPS according to MORPHOROGY) showed significant differences in Cranium region, Chest region, Stomatch region and Umbilicum region. 6. The analysis of the correlation in BAZ measurement values and Group(Cerebral Vascular Attack)showed significant differences, the analysis on the correlation of BAZ measurement values and Type(SaSang Constitution Classfication) didn't show any significant differences. 7. In comparison with Actual measurement vales and Voll's measurement values, BAZ measurement values agree with Voll's measurement values but CMP measurement values lower than the Voll's measurement values. Later We have to research further about classifications of race, age, sex etc. The EAV measurement values have Group(Cerebrovascular accident) more correlative than Type(SaSang Constitution Classfication). The EAV may well be that it will be used as an accessory method in SaSang Constitution Classfication and as a diagnostic method in medicine too.

• Journal of Korean Society for Quality Management
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• v.18 no.1
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• pp.84-95
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• 1990

The objective of this study is to understand the effect of measurement-related investment. That is, this study aims at verifying the correlation between the measurement-related investment and inferiority rate of products by statistical analysis. The samples of this study are 376 industrial companies in Korea, and the research data was analysed on inferiority state of industrial companies with a measurement standard laboratory. The analysis was made by the elementary statistics, the correlation analysis and the regression analysis. The results are summarized as follows : First, the inferioriy rate of the industrial companies with a measurement standard laboratory was relatively lower than that of the other companies without the laboratory by statistical significance. Second, the increment on measurement-related investment had a negative correlation with the increment of inferiority rate, and the increase of measurement-related investment showed decrease of the inferiority rate by regression analysis.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.7
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• pp.1024-1031
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• 2012

In this paper, FMCW type radar level transmitter using correlation analysis method is implemented for precise distance measurement of cargo tank. FMCW type radar level transmitter is the device for distance measurement which calculates the distance by analyzing the beat frequency, that is, the frequency difference between Tx and RX signal from radar antenna using Fast Fourier Transform(FFT), but compensated algorithm like Zoom FFT is needed for the improvement of the frequency precision because the frequency precision of FFT is limited depending on sampling frequency and the number of sampling data. In case of Zoom FFT, the number of sampling data and noisy signal are the main factor influencing the measurement accuracy of Zoom FFT like FFT. Therefore, in order to overcome the limited environment and achieve the precise measurement, correlation coefficient is used for the distance measurement and the errors of measurement are verified to be in the range of ${\pm}1mm$.

• Journal of information and communication convergence engineering
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• v.16 no.1
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• pp.38-42
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• 2018

In this paper, we consider measurement allocation problem in a spatially correlated sensor field. Our goal is to determine the probability of each sensor's being measured based on its contribution to the estimation reliability; it is desirable that a sensor improving the estimation reliability is measured more frequently. We consider a spatial correlation model of a sensor field reflecting transmission power limit, noise in measurement and transmission channel, and channel attenuation. Then the estimation reliability is defined distortion error between event source and its estimation at sink. Motivated by the correlation nature, we model the measurement allocation problem into a cooperative game, and then quantify each sensor's contribution using Shapley value. Against the intractability in the computation of exact Shapley value, we deploy a randomized method that enables to compute the approximate Shapley value within a reasonable time. Besides, we envisage a measurement scheduling achieving the balance between network lifetime and estimation reliability.

• Proceedings of the KIEE Conference
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• 1998.07g
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• pp.2430-2432
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• 1998

Generally, in the best-known Pulse-type type and Frequency Modulated Continuous Wave(FM/CW)-type RF range measurement systems, the nearest measurable distance between antenna of system and targets is limited to several tens of meters. Moreover, in case of high-speed targets it is more difficult to measure the distance precisely. In this paper we design our own RF(X-band) range(up to 15 meters) measurement system usi code correlation for high- speed targets. It 0 the correlation value between transmitting receiving PN (Pseudo -Noise) codes. So we determine the distance between antenna of s and targets using this correlation value. We fabricated it using MIC techniques and experimental results show that the proposed syste fully qualified for a short range measurement syste

• Implantology
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• v.22 no.4
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• pp.210-218
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• 2018

Purpose: The purpose of this study was to investigate the validity and reproducibility of a method based on cone-beam computed tomography (CBCT) technology for the visualization and measurement of gingival soft-tissue dimensions. Material and Methods: A total of 66 selected points in soft-tissue of the ex vivo head of an adult pig were investigated in this study. For the measurement of radiographic thickness (RT), wet soft-tissue surfaces were lightly covered with barium sulfate powder using a powder spray. CBCT was taken and DICOM files were assessed for soft-tissue thickness measurement at reference points. A periodontal probe and a rubber stop were used for the measurement of trans-gingival probing thickness (TPT). After flap elevation, actual thickness of soft-tissue (actual thickness, AT) was measured. Correlation analysis and intraclass correlation coefficients analysis (ICC) were performed for AT, TPT, and RT. Results: All variables were distributed normally. Strong significant correlations of AT with RT and TPT values were found. The two ICC values between TPT vs. AT and RT vs. AT differed significantly. Conclusion: Our results indicated that correlation of RT was stronger than that of TPT with AT. We concluded that soft tissue measurement with CBCT could be a reliable method, compared to the trans-gingival probing measurement method.

• Journal of Korean Society for Atmospheric Environment
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• v.3 no.2
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• pp.53-61
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• 1987

Automatic and manual rain smaplers wre installed at the roof of National Institute of Environmental Research (NIER), and the rain sampling and measurement were conducted during the period April to August 31, 1987. The rain sampling and measurement were carried out in the following manners: The 1st : Acidity and conductivity were measured entirely by automatic rain sampler (continuous measurement) The 2nd : Acidity and conductivity wrer measured in the laboratory with the sample that was taken out of automatic rain sampler. The 3rd : Acidity and conductivity were measured in the laboratory with the sample that was taken out of manual rain sampler. Afterwards, those different measurement values were compared each other and the following conclusions were obtained: 1) The pH of the continous measurement by the automatic sampler was lower than that of the laboratory measurement, and it was reversed in case of the conductivity. 2) The significance was recognized at 5% risk ratio for the population mean of difference of the measurement values of the pH and conductivity from both samples. 3) The significance was not recognized at 5% risk ratio by the analysis of variance by one way layout for the pH and conductivity. 4) The significance was recognized at 5% risk ratio by the analysis of variance by two way layouts for the pH conductivity. 5) The significance was recognized at 5% rrisk ratio for the differences of the pH values obtained by oboth samplers, and no significance was recognized for conductivity. 6) In comparison of the measurement values from the two samplers were shown a good correlation for pH; correlation coefficient (r) = 0.63, and regression equation Y = 0.53X + 2.78. For conductivity, the correlation was also excellent; correlation coefficient (r) = 0.53 and regression equation Y = 0.63X + 5.65.