• Journal of Korean Society for Geospatial Information Science
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• v.20 no.2
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• pp.93-100
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• 2012

The interest in 3-dimensional information and its practical use are rapidly increasing and thus some goods with stereoscopic views are being released. Mobile phones, unlike other units, are being closely utilized in everyday life and their applications are undoubtedly limitless. In this study, taking photographs with the stereo-camera of mobile phones has been accomplished and also the possibility of getting the quantitative information has been examined. In addition, this study aims to evaluate the quantitative practical use of mobile phones, evaluating the accuracy of the obtained quantitative information. Thus, interior orientation parameters were decided through the calibration of the lens of two cameras equipped with mobile phones. Using the determined interior orientation parameters, the 3-dimensional coordinates on the targets of the test field were calculated and then compared with precisely observed coordinates. Moreover, the performance of the orientation on the arbitrary building resulted in the standard deviation of $X={\pm}0.0674m$, $Y={\pm}0.25319$, and $Z={\pm}0.4983m$. The result also shows that the plot is possible. As a result, smart phones could be utilized for the acquisition of the quantitative information at close range and small measurement in which the high-accuracy on the basis of centimeters is not required.

• Korean Journal of Radiology
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• v.22 no.7
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• pp.1077-1086
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• 2021

Objective: To investigate the diagnostic performance of quantitative ultrasound (US) parameters for the assessment of hepatic steatosis in patients with nonalcoholic fatty liver disease (NAFLD) using magnetic resonance imaging proton density fat fraction (MRI-PDFF) as the reference standard. Materials and Methods: In this single-center prospective study, 120 patients with clinically suspected NAFLD were enrolled between March 2019 and January 2020. The participants underwent US examination for radiofrequency (RF) data acquisition and chemical shift-encoded liver MRI for PDFF measurement. Using the RF data analysis, the attenuation coefficient (AC) based on tissue attenuation imaging (TAI) (AC-TAI) and scatter-distribution coefficient (SC) based on tissue scatter-distribution imaging (TSI) (SC-TSI) were measured. The correlations between the quantitative US parameters (AC and SC) and MRI-PDFF were evaluated using Pearson correlation coefficients. The diagnostic performance of AC-TAI and SC-TSI for detecting hepatic fat contents of ≥ 5% (MRI-PDFF ≥ 5%) and ≥ 10% (MRI-PDFF ≥ 10%) were assessed using receiver operating characteristic (ROC) analysis. The significant clinical or imaging factors associated with AC and SC were analyzed using linear regression analysis. Results: The participants were classified based on MRI-PDFF: < 5% (n = 38), 5-10% (n = 23), and ≥ 10% (n = 59). AC-TAI and SC-TSI were significantly correlated with MRI-PDFF (r = 0.659 and 0.727, p < 0.001 for both). For detecting hepatic fat contents of ≥ 5% and ≥ 10%, the areas under the ROC curves of AC-TAI were 0.861 (95% confidence interval [CI]: 0.786-0.918) and 0.835 (95% CI: 0.757-0.897), and those of SC-TSI were 0.964 (95% CI: 0.913-0.989) and 0.935 (95% CI: 0.875-0.972), respectively. Multivariable linear regression analysis showed that MRI-PDFF was an independent determinant of AC-TAI and SC-TSI. Conclusion: AC-TAI and SC-TSI derived from quantitative US RF data analysis yielded a good correlation with MRI-PDFF and provided good performance for detecting hepatic steatosis and assessing its severity in NAFLD.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2001.10a
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• pp.38-42
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• 2001

A complete quantitative understanding of DT has been difficult because the process represents such a broad field of research. The experimental measurement of tool force is a single area of DT which still covers a wide range of possibilities. There are numerous parameters of the process which affect cutting forces. There are also many turnable materials of current interest. To obtain information toward a better understanding of the process, a few cutting parameters and materials were selected for detail study. It was decided that free-oxygen copper and 6061-T6 alloy aluminum would be the primary test materials. There are materials which other workers have also used because of there wide use in reflective applications. The experimental phase of the research project began by designing tests to isolate certain cutting parameters. The parameters chosen to study were those that affected the cross-sectional area of the uncut chip. The specific parameters which cause this area to vary are the depth of cut and infeed per revolution, or feedrates. Other parameter such a tool nose radius and surface roughness were investigated as they became relevant to the research.

• Transactions of Materials Processing
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• v.14 no.1 s.73
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• pp.21-28
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• 2005

This paper is concerned with the quantitative effect of design parameters on a stamped part of the auto-body. The considered parameters in this paper are the blank holding force, the draw-bead force, the blank size which greatly affect the metal flow during stamping. The indicators of formability selected in this paper are failures such as tearing, wrinkling and the amount of springback. The stamping process of the front side inner member is simulated using the finite element analysis changing the design parameters. The numerical results demonstrate that the blank holding force cannot control the local metal flow during forming although it controls the overall metal flow. The modification of the initial blank size considering the punch opening line ensures the local wrinkling and reduces the amount of springback after forming. The restraining force of draw-bead controls the metal flow in the local area and reduces the amount of excess metal. It is noted that the parametric study of design parameters such as blank holding force, the blank size and the draw-bead are very important in the process design of the complicated member.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.10a
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• pp.957-960
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• 1997

A complete quantitative understanding of DT has been difficult because the process represents such s broad field of research. The experimental measurement of tool force is a single area of DT which still covers a wide range of possibilities. Here are numerous parameters of the process which affect cutting forces. There are also many turnable materials of current interest. To obtain information toward a better understanding of the process, a few cutting parameters and materials were selected for detail study. It was decided that free-oxygen copper and 6061-T6 alloy aluminum would be the primary test materials. There are materials which other workers have also used because of there wide use in reflective applications. The experimental phase of the research project began by designing tests to isolate certain cutting parameters. The parameters chosen to study were those that affected the cross-sectional area of the uncut chip. The specific parameters which cause this area to vary are the depth of cut and infeed per revolution, or feedrates. Other parameter such a tool nose radius and surface roughness were investigated as they became relevant to the research.

• Fisheries and Aquatic Sciences
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• v.9 no.4
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• pp.167-174
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• 2006

Two typical responses have been documented for flatfish when they encounter the ground gear of bottom trawls: herding response and falling back response. These two responses were analyzed from video recordings of fish and were characterized by time sequences for four parameters: swimming speed, angular velocity, acceleration, and distance between the fish and the ground gear. When flatfish displayed the falling-back response, absolute values of the three swimming parameters and their deviations were significantly higher than those during the herding response. However, the swimming parameters were not dependent on the distance between the flatfish and the ground gear, regardless of which response occurred. The dominant periods for most of the movement parameters ranged from 2.0 to 3.7 s, except that no periodicity was observed for swimming speed or angular velocity during the falling-back response. However, variations in the four parameters during the falling -back response revealed greater irregularity in periodicity and higher amplitudes. This complex behavior is best described as a chaos phenomenon' and is discussed as the building block for a model predicting the responses of flatfish to ground gear as part of the general understanding of the fish capture process.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.21 no.6
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• pp.951-960
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• 1997

Package crack caused by the soldering process in the surface mounting plastic package is evaluated by applying the maximum energy release rate criterion. It could be shown that the crack propagation from the lower edge of the ie pad is easily occurred at the maximum temperature during the soldering process, where the pressure acting on the crack surface is assumed by the saturated vapor pressure at maximum temperature. The package crack formation depends on various parameters such as chip size, relative thickness, material properties, the moisture content and soldering temperature etc. The quantitative measure of the effects of the parameters could be easily obtained by using the taguchi's method which requires only a few kinds of combinations with such parameters. From the results, it could be obtained that the more significant parameters to effect the package reliability are the orders of Young's modulus, die pad size, down set, chip thickness and maximum soldering temperature.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.19 no.1
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• pp.75-85
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• 2021

Evaluating the quantitative damage to rocks through acoustic emission (AE) has become a research focus. Most studies mainly used one or two AE parameters to evaluate the degree of damage, but several AE parameters have been rarely used. In this study, several data-driven models were employed to reflect the combined features of AE parameters. Through uniaxial compression tests, we obtained mechanical and AE-signal data for five granite specimens. The maximum amplitude, hits, counts, rise time, absolute energy, and initiation frequency expressed as the cumulative value were selected as input parameters. The result showed that gradient boosting (GB) was the best model among the support vector regression methods. When GB was applied to the testing data, the root-mean-square error and R between the predicted and actual values were 0.96 and 0.077, respectively. A parameter analysis was performed to capture the parameter significance. The result showed that cumulative absolute energy was the main parameter for damage prediction. Thus, AE has practical applicability in predicting rock damage without conducting mechanical tests. Based on the results, this study will be useful for monitoring the near-field rock mass of nuclear waste repository.

• Analytical Science and Technology
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• v.14 no.4
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• pp.1075-1081
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• 2001

Instrumental Neutron Activation Analysis as a representative method of nuclear analytical technique, has advantages of non-destructive, simultaneous multi-element analysis with the characteristics of absolute measurement method. Up to date, $k_0$-quantitative method which is accurate, convenient and user-friendly, has been generalized world-widely. In this study, it is intented to introduce the general concept of $k_0$-method and to measure $k_0$-parameters for the future implementation to our NAA system. For this objectives, the definition of relevant factors for the quantitative analysis and the equation for the experimental determination of parameters such as $Q_0$(${\alpha}$) and f were summarized. Furthermore, a foundation for the $k_0$-standardization method was prepared through the measurement of ${\alpha}$ and f-value which depend on the specific character of irradiation hole at NAA#1-hole of HANARO research reactor.

• The Journal of Korean Medicine
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• v.35 no.4
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• pp.74-82
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• 2014

Objectives: Quantification, objectification, and standardization of lifting-thrusting manipulation are important issues in traditional Chinese medicine (TCM). The purpose of this study was to quantitatively investigate the difference in the amount of stimulation according to range and frequency among parameters of lifting-thrusting manipulation with the use of a needle insertion-measurement system. Methods: For quantification of lifting-thrusting manipulation, an acupuncture needle insertion-measurement system was used in phantom tissue. The motor and force sensors of the needle insertion device were connected to the control software. This enabled operation of the lifting-thrusting manipulation and measurement of the acupuncture needle force. The measurement of the acupuncture needle force according to various frequencies (0.25, 0.50, 0.75, and 1 Hz) and ranges of movement (2, 4, 6, 8, and 10 mm) was repeated 10 times. Results: At a constant frequency of movement, acupuncture needle force according to range of movement (2, 4, 6, 8, and 10 mm) increased with increasing range of movement (p < 0.05). At a constant range of movement, acupuncture needle force according to frequency of movement (0.25, 0.50, 0.75, and 1.0 Hz) increased with increasing frequency of movement (p < 0.05). Conclusion: In this study, we conducted a quantitative comparison of the amount of stimulation according to range and frequency, the main parameters of lifting-thrusting manipulation, by using an acupuncture needle insertion-measurement system. Future studies on various manipulations and parameters are warranted to quantify and objectify the amounts of stimulation by acupuncture manipulation.