• Title/Summary/Keyword: A level-set method

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Estimation of Pollution Contribution TMDL Unit Watershed in Han-River according to hydrological characteristic using Flow Duration Curve (유량지속곡선을 이용한 수문특성별 한강수계 총량관리 단위유역의 오염기여도 추정)

  • Kim, Dong Young;Yoon, Chun Gyeong;Rhee, Han Pil;Choi, Jae Ho;Hwang, Ha Sun
    • Journal of Korean Society on Water Environment
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    • v.35 no.6
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    • pp.497-509
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    • 2019
  • After the Total Maximum Daily Loads(TMDLs) was applied, it became beyond the limit of concentration management. However, it does not adequately reflect the characteristics of various watersheds, and causes problems with local governments because of the standard flow set. Thus, in this study, the Han River system is organized into four groups in estimating the Pollution Contribution by applying the Flow Duration Curve(FDC) created by the daily flow of data from the HSPF. And the method of this study is expected to be valuable as basic data for the TMDLs. As a result, Group I contains the main watersheds with no large hydraulic structures and tributary watersheds. There is no specificity in the FDC and the Pollution Contribution is estimated as rainfall runoff. Group II contains watersheds near the city where the FDC is maintained above a certain level during the Low Flow Conditions and the Pollution Contribution is estimated as the discharge flow of large scale point pollution facilities. Group III contains the main watersheds in which the large hydraulic structures are installed and FDC is curved in the Low Flow Conditions. So the Pollution Contribution is estimated as the water quality of the large hydraulic structures. Group IV contains the upstream in mainstream watersheds in which the large hydraulic structures are installed and the FDC is disabled before the Low Flow Conditions. As the flow is concentrated in the High Flow Conditions, the non-point pollution sources are estimated as the Pollution Contribution.

Core Circuit Technologies for PN-Diode-Cell PRAM

  • Kang, Hee-Bok;Hong, Suk-Kyoung;Hong, Sung-Joo;Sung, Man-Young;Choi, Bok-Gil;Chung, Jin-Yong
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.8 no.2
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    • pp.128-133
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    • 2008
  • Phase-change random access memory (PRAM) chip cell phase of amorphous state is rapidly changed to crystal state above 160 Celsius degree within several seconds during Infrared (IR) reflow. Thus, on-board programming method is considered for PRAM chip programming. We demonstrated the functional 512Mb PRAM with 90nm technology using several novel core circuits, such as metal-2 line based global row decoding scheme, PN-diode cells based BL discharge (BLDIS) scheme, and PMOS switch based column decoding scheme. The reverse-state standby current of each PRAM cell is near 10 pA range. The total leak current of 512Mb PRAM chip in standby mode on discharging state can be more than 5 mA. Thus in the proposed BLDIS control, all bitlines (BLs) are in floating state in standby mode, then in active mode, the activated BLs are discharged to low level in the early timing of the active period by the short pulse BLDIS control timing operation. In the conventional sense amplifier, the simultaneous switching activation timing operation invokes the large coupling noise between the VSAREF node and the inner amplification nodes of the sense amplifiers. The coupling noise at VSAREF degrades the sensing voltage margin of the conventional sense amplifier. The merit of the proposed sense amplifier is almost removing the coupling noise at VSAREF from sharing with other sense amplifiers.

Reliability and Validity Study on the Korean Version of the Fullerton Advanced Balance Scale (한국어판 플러턴 어드밴스드 균형 척도의 신뢰도와 타당도 연구)

  • Kim, Gyoung-mo
    • Physical Therapy Korea
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    • v.23 no.1
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    • pp.31-37
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    • 2016
  • Background: The assessment tool developed in other countries should be translated into Korean language using rigorous methodological approaches in order to be used in Korea. Because these procedures are insufficient for establishing the cross-cultural and linguistic equivalence, the need for statistical methods is raised. The Fullerton Advanced Balance Scale was translated into Korean and the content validity was verified through the back translation method, but the reliability and validity have not yet been proven by statistical methods. Objects: The purpose of this study was to investigate the reliability and validity of the Korean version of the Fullerton Advanced Balance Scale (KFAB) by statistical methods in elderly people. Methods: A total of 97 elderly adults (39 males and 58 females) participated in this study. Internal consistency of the KFAB was measured using Cronbach's alpha and an intraclass correlation coefficient (ICC) was used to assess test-retest reliability between the two measurement sessions. Concurrent validity was measured by comparing the KFAB responses with the Korean version of the Berg Balance Scale (KBBS) using the Spearman correlation coefficient. Construct validity of the KFAB was measured using the exploratory factor analysis to evaluate the unidimensionality of the questionnaire. The significance level was set at ${\alpha}=.05$. Results: The internal consistency of the KFAB was found be adequate with Cronbach's alpha (.96), and test-retest reliability was excellent as evidenced by the high ICC (r=.996). Concurrent validity showed high correlation between the KFAB and KBBS (r=.89, p<.001). Construct validity was evaluated using exploratory factor analysis. The result from Bartlett test of sphericity was statistically significant (p<.001), and the value of Kaiser-Meyer-Olkin measure of sampling adequacy was .93. Exploratory factor analysis revealed the existence of only one dominant factor that explained 76.43% of the variance. Conclusion: The KFAB is a reliable, valid and appropriate tool for measuring the balance functions in elderly people.

Ovarian Cancer Microarray Data Classification System Using Marker Genes Based on Normalization (표준화 기반 표지 유전자를 이용한 난소암 마이크로어레이 데이타 분류 시스템)

  • Park, Su-Young;Jung, Chai-Yeoung
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.15 no.9
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    • pp.2032-2037
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    • 2011
  • Marker genes are defined as genes in which the expression level characterizes a specific experimental condition. Such genes in which the expression levels differ significantly between different groups are highly informative relevant to the studied phenomenon. In this paper, first the system can detect marker genes that are selected by ranking genes according to statistics after normalizing data with methods that are the most widely used among several normalization methods proposed the while, And it compare and analyze a performance of each of normalization methods with mult-perceptron neural network layer. The Result that apply Multi-Layer perceptron algorithm at Microarray data set including eight of marker gene that are selected using ANOVA method after Lowess normalization represent the highest classification accuracy of 99.32% and the lowest prediction error estimate.

Feature Extraction by Line-clustering Segmentation Method (선군집분할방법에 의한 특징 추출)

  • Hwang Jae-Ho
    • The KIPS Transactions:PartB
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    • v.13B no.4 s.107
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    • pp.401-408
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    • 2006
  • In this paper, we propose a new class of segmentation technique for feature extraction based on the statistical and regional classification at each vertical or horizontal line of digital image data. Data is processed and clustered at each line, different from the point or space process. They are designed to segment gray-scale sectional images using a horizontal and vertical line process due to their statistical and property differences, and to extract the feature. The techniques presented here show efficient results in case of the gray level overlap and not having threshold image. Such images are also not easy to be segmented by the global or local threshold methods. Line pixels inform us the sectionable data, and can be set according to cluster quality due to the differences of histogram and statistical data. The total segmentation on line clusters can be obtained by adaptive extension onto the horizontal axis. Each processed region has its own pixel value, resulting in feature extraction. The advantage and effectiveness of the line-cluster approach are both shown theoretically and demonstrated through the region-segmental carotid artery medical image processing.

A Study of Stress off City Gas Pipe Attached on the Bridge (교량에 부착된 도시가스 배관의 응력에 관한 연구)

  • Lee Su-Kyung;Lim Bong-Gwan
    • Journal of the Korean Institute of Gas
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    • v.10 no.3 s.32
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    • pp.20-26
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    • 2006
  • The survey team has conducted the on-the-site inspection of 53 bridges to which LNG gas pipelines are attached, to ascertain their level of safety, durability and any defect by adapting a method of computer data input process and precision analysis. In this way, we could estimate an effective corrective action on the defective gas pipelines found through this survey. Our survey team has analyzed carefully these 2 defective lines selectively out of 10 lines, which are considered to be most seriously weak. According to our elaborate analysis these two pipelines go over 70% of the set standard stress based on our Safety Manual Scale. We have taken corrective actions on these lines by repairing/replacing/obsolete damaged lines to ensure the distress of the bridges involved with the pipelines and could secure safety.

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Fault Tolerant Cache for Soft Error (소프트에러 결함 허용 캐쉬)

  • Lee, Jong-Ho;Cho, Jun-Dong;Pyo, Jung-Yul;Park, Gi-Ho
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.57 no.1
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    • pp.128-136
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    • 2008
  • In this paper, we propose a new cache structure for effective error correction of soft error. We added check bit and SEEB(soft error evaluation block) to evaluate the status of cache line. The SEEB stores result of parity check into the two-bit shit register and set the check bit to '1' when parity check fails twice in the same cache line. In this case the line where parity check fails twice is treated as a vulnerable to soft error. When the data is filled into the cache, the new replacement algorithm is suggested that it can only use the valid block determined by SEEB. This structure prohibits the vulnerable line from being used and contributes to efficient use of cache by the reuse of line where parity check fails only once can be reused. We tried to minimize the side effect of the proposed cache and the experimental results, using SPEC2000 benchmark, showed 3% degradation in hit rate, 15% timing overhead because of parity logic and 2.7% area overhead. But it can be considered as trivial for SEEB because almost tolerant design inevitably adopt this parity method even if there are some overhead. And if only parity logic is used then it can have $5%{\sim}10%$ advantage than ECC logic. By using this proposed cache, the system will be protected from the threat of soft error in cache and the hit rate can be maintained to the level without soft error in the cache.

Characteristics on the Extreme Value Distributions of Deepwater Design ave Heights off the Korean Coast (한국 연안 심해 설계파고의 극치분포 특성)

  • Shin Taek Jeong;Jeong Dae Kim;Cho Hong Yeon
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.16 no.3
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    • pp.130-141
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    • 2004
  • For a coastal or harbor structure design, one of the most important environmental factors is the appropriate design wave condition. Especially, the information of deepwater wave height distribution is essential for reliability design. In this paper, a set of deep water wave data obtained from KORDI(2003) were analyzed for extreme wave heights. These wave data at 67 stations off the Korean coast from 1979 to 1998 were arranged in the 16 directions. The probability distributions considered in this research were the Weibull, the Gumbel, the Log-pearson Type-III, and Lognormal distribution. For each of these distributions, three parameter estimation methods, i.e. the method of moments, maximum likelihood and probability weighted moments, were applied. Chi-square and Kolmogorov-Smirnov goodness-of-fit tests were performed, and the assumed distribution was accepted at the confidence level 95%. Gumbel distribution which best fits to the 67 station was selected as the most probable parent distribution, and optimally estimated parameters and 50 year design wave heights were presented.

Effect of Aquatic Walking Exercise on Gait and Balance Parameters of Elderly Women (수중걷기운동이 여성노인의 보행 및 평형능력에 미치는 영향)

  • Kang, Ki-Joo;Lee, Joong-Sook;Yang, Jeong-Ok;Park, Joon-Sung;Han, Ki-Hoon
    • Korean Journal of Applied Biomechanics
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    • v.30 no.1
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    • pp.73-81
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    • 2020
  • Objective: The purpose of this study is to analyze the effects of aquatic walking exercise on gait and balance parameters of elderly women. Method: 15 elderly people were recruited for this study (age: 73.20±5.19 yrs, height: 153.87±3.36 cm, mass: 60.33±5.73 kg). All variables were measured using Gaitview AFA-50. The variables were the heel contact time ratio, gait angle, and M/P change ratio for gait patterns and ENV, REC, RMS, Total Length, TLC, Sway velocity, and Length/ENV for balance abilities. A paired t-test and the Wilcoxon signed-rank test were carried out to verify the differences in the test scores after participating in the water walking program. The significance level for all statistical analyses was set to α=.05. Results: As for the changes in their walking function after the exercise, heel contact time ratio (p<.01) showed a statistical significance, while gait angle and M/P change ratio did not reveal statistically significant differences. In the test of balance ability on both feet and with eyes opened, statistical significance was found in ENV, REC, RMS, TLC (p<.01), and sway velocity (p<.05), while the test with eyes closed showed statistical significance in length/ENV as well as ENV, REC, RMS, sway velocity (p<.01) TLC, and total length (p<.05). As for the single-leg stance balance ability, ENV and REC revealed statistically significant differences. Conclusion: These results show that water walking is effective for improving the function of the ankle flexor muscles, providing stability to the ankle joint during walking and helping efficient walk. In addition, it is also expected to help prevent falls due to loss of balance by improving the stability of lower extremity muscles and trunk.

The Effect of Career Choice Motives of the Private Security Guards on Job evaluation and Job Attitude (민간경비원의 직업선택동기가 직업선택평가 및 직무태도에 미치는 영향)

  • Kim, Sang-Jin
    • Convergence Security Journal
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    • v.16 no.6_2
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    • pp.73-82
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    • 2016
  • This study is to investigate the Effect of Career Choice Motives of the Private Security Guards on Job choice evaluation and Job Attitude. For this study visiting the 8 companies around the capital area and surveyed from May 1st to October 10th 2015 using the stratified random sampling method. A total of 240 questionnaires were distributed and among them, 220 copies were used except for analysis. I used SPSSWIN 21.0 and AMOS 21.0 to reliability analysis, factor analysis, analysis of structural equation model, path analysis. The level of statistical significance was set to .05. The following are conclusions. Job choice motivation has a positive effect on Job choice evaluation and Job attitude but Job choice evaluation doesn't play intermediary role on relationship between Job choice motivation and Job attitude.