• The Transactions of the Korea Information Processing Society
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• v.6 no.10
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• pp.2816-2822
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• 1999

In this paper, a fast thinning method for fingerprint image by separating end and bifurcation region is proposed. To detect feature points in automatic fingerprint identification system, thinning of fingerprint is essential. The end and bifurcation regions in ridge line are separated by means of run-length coding, and parallel thinning method is applied to the separated regions. The rest parts except the end and bifurcation regions are processed by connecting center points of each run. The performance of the proposed method has been evaluated by CPU processing time and thinness measurement. By the experimental results, the proposed method is fast and has high thinness value.

• Journal of applied mathematics & informatics
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• v.42 no.3
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• pp.709-723
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• 2024

We study the distributions of waiting times in variations of the geometric distribution of order k. Variation imposes length on the runs of successes and failures. We study two types of waiting time random variables. First, we consider the waiting time for a run of k consecutive successes the first time no sequence of consecutive k failures occurs prior, denoted by T^(k). Next, we consider the waiting time for a run of k consecutive failures the first time no sequence of k consecutive successes occurred prior, denoted by J^(k). In addition, we study the distribution of the weighted average. The exact formulae of the probability mass function, mean, and variance of distributions are also obtained.

• Journal of Welding and Joining
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• v.26 no.6
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• pp.42-47
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• 2008

TIG welding enables to produce high quality weldment. However it has some problems such as shallow penetration and large distortion due to low penetration aspect ratio after welding. In order to overcome those problems, there are many ongoing studies on A-TIG welding, which use active flux. In this study, the effect of arc length and shield gas on penetration aspect ratio with melt-run welding on STS 304 6t, on which active flux was spreaded, was investigated. Arc length was changed from 1mm to 3mm, and aspect ratio became higher as arc length was decreased in this range. 100% Ar gas, Ar-$H_2$ mixed gas, Ar-He mixed gas, and 100% He gas were used as shield gas in this study. When Ar-$H_2$ mixed gas, Ar-He mixed gas, and 100% He gas were applied, penetration and melting efficiency were both increased as compared with 100% Ar gas. Aspect ratio was the highest with Ar-2.5% $H_2$ mixed gas.

• Journal of the Korean GEO-environmental Society
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• v.2 no.1
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• pp.31-35
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• 2001

The effects of the ratio of effective size of filter media and diatom size on filter run time were evaluated by using both reported data and experimental results from several water treatment plants. For single media at several WTPs, the range of probability of the filter run time less than 15hr was 10~60%, and for dual media, that of the filter run time less than 30hr was 10~20%. The major filter clogging algae was Synedra acus of which dominant ratio was in the range of 64~92%. The effective size(ES) of filter medium for dual media filter was 0.71~1.40mm and uniformity coefficient of the filter was 1.25~1.67. The effective size(ES) of filter medium for single medium filter was 0.52~0.65mm and uniformity coefficient of the filter was 0.25~1.40. The range of calculated penetration depth was 2.58~15.4cm for dual media and 1.29~2.17cm for single media, and average filter run time was 40.1~83.3hr and 13.9~34.9hr, respectively. When Synedra counts were over 400cells/ml for single media, filter run time was below 5hr, while filter run time for dual media filter, remained as high as 70hr.

• Korean Journal of Applied Biomechanics
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• v.21 no.5
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• pp.603-610
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• 2011

The long jump motions of 8 finalists in the women's long jump at the IAAF World Championships, Daegu 2011 were analyzed, and the kinematic characteristics of their techniques were investigated. The kinematic characteristics of the long jump motion of the 8 finalists were as follows. In the run-up phase, the length of the 2 stride was $108{\pm}6.92%$ that of the 3 stride. The length of the 1 stride was $91{\pm}5.78%$ that of the 2 stride. The change in the height of the center of gravity was $0.07{\pm}0.03$ m. The maximum velocity during the run-up phase was $9.44{\pm}0.13$ m at the 1 stride. In the take-off phase, the horizontal velocity, vertical velocity, reduction in horizontal velocity were $7.80{\pm}0.15$ m/s, $2.96{\pm}0.14$ m/s, and $1.64{\pm}0.19$ m/s, respectively. The minimum knee angle and take-off angle were $151{\pm}8.89^{\circ}$ and $20.7{\pm}1.03^{\circ}$, respectively. In the flight phase, the flight time and maximum height of the center of gravity were $0.78{\pm}0.03$ s, and $1.60{\pm}0.05$ m, respectively. In the landing phase, the landing length was $0.50{\pm}0.07$ m. The trunk angle, knee angle, and hip angle were $74{\pm}18.75^{\circ}$, $131{\pm}10.45^{\circ}$, and $82{\pm}9.03^{\circ}$, respectively. The kinematic characteristics of the motion of a good long jump were as follows. The reduction in the horizontal velocity in the take-off phase was minimized, and the maximum velocity of the run-up was maintained. The vertical velocity in the take-off phase was increased using a rapidly extended knee and high center of gravity.

• Journal of Internet Computing and Services
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• v.16 no.1
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• pp.29-37
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• 2015

In this paper, we propose a robust pre-processing module for camera-based Optical Music Score Recognition (OMR) on mobile device. The captured images likely suffer for recognition from many distortions such as illumination, blur, low resolution, etc. Especially, the complex background music sheets recognition are difficult. Through any symbol recognition system, the staff line height and staff line space are used many times and have a big impact on recognition module. A robust and accurate staff line height and staff line space are essential. Some staff line height and staff line space are proposed for binary image. But in case of complex background music sheet image, the binarization results from common binarization algorithm are not satisfactory. It can cause incorrect staff line height and staff line space estimation. We propose a robust staff line height and staff line space estimation by using run-length encoding technique on edge image. Proposed method is composed of two steps, first step, we conducted the staff line height and staff line space estimation based on edge image using by Sobel operator on image blocks. Each column of edge image is encoded by run-length encoding algorithm Second step, we detect the staff line using by Stable Path algorithm and removal the staff line using by adaptive Line Track Height algorithm which is to track the staff lines positions. The result has shown that robust and accurate estimation is possible even in complex background cases.

• Journal of the Korean Data and Information Science Society
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• v.13 no.1
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• pp.105-112
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• 2002

In this paper we establish bivariate exponentially weighted moving average (EWMA) control charts for autocorrelated processes using residual vectors. We first derive the residual vectors, their expectation, variance-covariance matrix, then evaluate the control chart based on the average run length (ARL).

• ETRI Journal
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• v.33 no.1
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• pp.140-143
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• 2011

Recent test data compression techniques raise concerns regarding power dissipation and compression efficiency. This letter proposes a new test data compression scheme, twin symbol encoding, that supports block division skills that can reduce hardware overhead. Our experimental results show that the proposed technique achieves both a high compression ratio and low-power dissipation. Therefore, the proposed scheme is an attractive solution for efficient test data compression.

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 1987.04a
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• pp.31-34
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• 1987

A new efficientcoding system which can transmit video conferenceof viedeophone signals at a 64kbps is proposed. In addition to the interframe and CRC (Conditional Repleni shment Coding) system, BTVQ (Binary Tree searched Vector Quantizer)and RLC (Run Length Coding) methods are incorporated. Couble buffer memory is used for simple comtrol of channel symbol transmission and memory underflow And also buffer memory onerfolw is easily controlled by the thresholds of a MAD (Moving Area Betector)

• Journal of Korean Society for Quality Management
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• v.26 no.3
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• pp.31-45
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• 1998

This paper proposes a method of designing one-sided cumulative scored control charts to control the process mean with a normally distributed quality characteristic. The average run length(ARL) is obtained from the average sample number of sequential probability ratio test(SPRT) on trinomial distribution. Using the analogy between cumulative scored control chart and SPRT for trinomial observations, a procedure is presented to determine three control chart parameters; lower and u, pp.r scoring boundaries and action limit. The parameters are determined by minimizing the ARL when the process is out of control with prespecified ARL when the process is in control.