• Transactions of the Korean Society of Mechanical Engineers B
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• v.27 no.8
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• pp.1071-1080
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• 2003

A national standard system was developed in order to calibrate and test the oil flowmeters for the petroleum field. A stop valve and a gyroscopic weighing scale were employed for the primary standard of the flow quantity. It is operated by the standing start and finish mode and the static weighing method. The model equation for uncertainty evaluation was based on the calibration principle of standard system. The sources of the uncertainties were quantified and combined according to the GUM(Guide to the Expression of Uncertainty in Measurement). It was found that the standard system had the relative expanded uncertainty of 0.04 % in the range of 18 - 350 ㎥/ｈ. According to the uncertainty budget, the uncertainties of the fluid density and the volume of pipeline, which were temperature dependent, contributed 92% of final uncertainty in the oil flow standard system.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2005.05a
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• pp.149-155
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• 2005

Was used at step space-time mainly after VE technique sponsors in domestic in the 1960s but have been expanded to design step recently. Possibility of value elevation or cost reduction must choose member that is effectively for active and effective application of VE technique. In this study, when enforce design VE examining for weight decision corrosion protection been using in weight grant composition estimation technique, target choice process wishes to suggest formality and method that can be achieved effectively. Main conclusion of this study sorts valuation items step by step for weight appropriation of valuation basis and give point on article of high position point after expert which employer is included estimates article by low rank step and this presented high position method that do union itembyitemandestablishesbyitemweight. Did these techniques for giving weights so that importance for weight appropriation developed estimation program, and data save of target estimation standard and target estimation standard is possible using straight sit.

• The KSFM Journal of Fluid Machinery
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• v.14 no.1
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• pp.42-47
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• 2011

Measurement uncertainty analysis of fuel flow using turbine flowmeter was performed for the case of altitude engine test. SAE ARP4990 was used as the fuel flow calculation procedure, as well as the mathematical model for the measurement uncertainty assessment. The assessment was performed using Sensitivity Coefficient Method. 11 parameters involved in the calculation of the flow rate were considered. For the given equipment setup, the measurement uncertainty of fuel flow was assessed in the range of 1.19~1.86 % for high flow rate case, and 1.47~3.31 % for low flow rate case. Fluctuation in frequency signal from the flowmeter had the largest influence on the fuel flow measurement uncertainty for most cases. Fuel temperature measurement had the largest for the case of low temperature and low flow rate. Calibration of K-factor and the interpolation of the calibration data also had large influence, especially for the case of very low temperature. Reference temperature, at which the reference viscosity of the sample fuel was measured, had relatively small contribution, but it became larger when the operating fuel temperature was far from reference temperature. Measurement of reference density had small contribution on the flow rate uncertainty. Fuel pressure and atmospheric pressure measurement had virtually no contribution on the flow rate uncertainty.

• Journal of Korea Multimedia Society
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• v.4 no.2
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• pp.136-144
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• 2001

visual cryptography is a simple method in which secret information can be directly decoded in human visual system without any cryptographic computations. This scheme is a kind of secret sharing scheme in which secret of image type is distributed to n random image(we call it share). When the secret image is distributed to n shares, the original pixel is expanded as much as the size of column in basis matrix. It causes the deterioration of contrast in docoded secret image. Therefore, many researches have performed to reduce the size of pixel expansion and to improve the contrast by overlapping the row in basis matrix for (k, n) visual cryptography. In addition, we show that the proposed method can construct the (k, n) visual cryptography with multiple contrasts depending on selecting k out of n slides in a group.

• Journal of Korea Multimedia Society
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• v.12 no.11
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• pp.1547-1556
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• 2009

In this paper, we propose a flame detection method using region expansions and on-line variances in outdoor infrared video sequences. To segment flame candidates' regions in infrared images, we first, extract initial regions by high threshold values in infrared images and then the segmented regions are expanded to their neighbors with similar high intensity values. The segmented regions could be non-flame areas like bare-grounds and buildings. Therefore, to detect flame regions in the segmented regions, the segmented regions which have high intensity values in infrared image, are tracked using bounding regions in frame sequences. Variances in the tracked regions are calculated effectively by on-line updates to measure intensity variations on the tracked regions. Experiments show that the proposed method, which is based on region expansions and the average of on-line variances in the regions, is efficient to detect flames in infrared image.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.7 no.4
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• pp.833-838
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• 2003

This paper presents novel methods of recognizing license plates of passing vehicles outdo(n. In particular, the proposed method is much robust for inclined plates caused by the changes of camera placement. To acquire fine images of quickly passing vehicles under a wide range of illumination conditions, we developed a sensing system having superb characteristics. We expanded the dynamic range and eliminated the blurring of images of fast moving vehicles by synthesizing a pair of synchronized images with different intensities. furthermore, to extend the flexibility of the positioning of the TV camera, we propose a recognition algorithm that can be applied to inclined plates. The performance of the integrated system was investigated on real images of vehicles captured under various illumination conditions. The recognition rates of over 99% (conventional plates) and over 97% (highly inclined plates) shows that the developed system is effective for license plate recognition.

• Journal of Embryo Transfer
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• v.32 no.2
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• pp.47-52
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• 2017

As a part of the effort to improve post-transfer survival rate of embryos in Korean black goats, a technique for laparoscopic uterine transfer of blastocysts was carried out. A total of 26 transferrable embryos (morula to expanded blastocysts) were transferred to 13 recipient goats via transabdominal laparoscopic method. In consequence of our hormone protocol, 65% of the recipients (13/20) were found to have synchronized estrus. After confirmation of corpus luteum in each recipient goat, a Babcock laparoscopic forceps was inserted into the lower abdominal cavity to hold a uterine horn and fasten it near the peritoneum without causing injury. Then 7.5cm long 16G IV catheter was inserted directly into the uterine lumen through the abdominal wall. After removal of the stylet of the IV catheter, the embryo transfer tube (identical in size to the stylet and loaded with blastocysts) was inserted into the uterine lumen through the catheter to unload the embryos. Of the 13 estrus synchronized recipients, 9 were transferred blastocysts and 4 were transferred molurae (2 embryos in each recipient) in uterine ipsilateral to the ovary with corpus luteum. Four of the 9 recipients which blastocysts were transferred using this method has been confirmed pregnant (44.4% pregnancy rate).

• The Journal of the Korea Contents Association
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• v.5 no.1
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• pp.135-145
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• 2005

Without detailed exact knowledge of a retrieval collection, most users find it difficult to formulate effective queries. In fact, most users may spend large amount of time formulating queries in order to obtain their desired result. A method to overcome this difficulty is to use query expansion that reformulates better query from initial query. In this paper we propose concept based query evaluation method using concept of class that retrieved from initial query. This concept is expanded through thesaurus. For efficiency evaluation of query expansion, we defined most critical value through a simulation and compared precision and recall each other.

• Communications of the Korean Mathematical Society
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• v.33 no.2
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• pp.677-693
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• 2018

In this work, we generalize a family of optimal eighth order weighted-Newton methods to Banach spaces and study its local convergence to approximate a locally-unique solution of a system of nonlinear equations. The convergence in this study is shown under hypotheses only on the first derivative. Our analysis avoids the usual Taylor expansions requiring higher order derivatives but uses generalized Lipschitz-type conditions only on the first derivative. Moreover, our new approach provides computable radius of convergence as well as error bounds on the distances involved and estimates on the uniqueness of the solution based on some functions appearing in these generalized conditions. Such estimates are not provided in the approaches using Taylor expansions of higher order derivatives which may not exist or may be very expensive or impossible to compute. The convergence order is computed using computational order of convergence or approximate computational order of convergence which do not require usage of higher derivatives. This technique can be applied to any iterative method using Taylor expansions involving high order derivatives. The study of the local convergence based on Lipschitz constants is important because it provides the degree of difficulty for choosing initial points. In this sense the applicability of the method is expanded. Finally, numerical examples are provided to verify the theoretical results and to show the convergence behavior.

• The Journal of the Acoustical Society of Korea
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• v.22 no.8
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• pp.660-669
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• 2003

This paper describes a theory to calculate sound source field from the spatial transform of sound field and the measured cross-power spectrum of sound pressure over a hologram plane close to a sound source, Calculating method is proposed to solve sound pressures from cross-power spectrums over a hologram plane, For this, Taylor series for the nonlinear equations is expanded, and it is calculated using Newton-Raphon method, Also, a wave number filter is used to reduce errors that is occurred on the backward propagation, and is performed numerical simulation of the circular piston sound source with infinite baffle in water to verify the proposed theory.