• The Journal of Korean Institute of Communications and Information Sciences
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• v.41 no.2
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• pp.244-253
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• 2016

The QRS complex of ECG signal represents the depolarization and repolarization activities in the cells of ventricle. Accurate informations of $QRS_{onset}$ and $QRS_{offset}$ are needed for automatic analysis of ECG waves. In this study, using the amount of change in the QRS complex voltage values and the distance from the $R_{peak}$, we determined the junction point from Q-wave to R-wave and the junction point from R-wave to S-wave. In the next step, using the integral calculation based on the connection point, we detected $QRS_{onset}$ and $QRS_{offset}$. We use the PhysioNet QT database to evaluate the performances of the algorithm, and calculate the mean and standard deviation of the differences between onsets or offsets manually marked by cardiologists and those detected by the proposed algorithm. The experiment results show that standard deviations are under the tolerances accepted by expert physicians, and outperform the results obtained by the other algorithms.

• Childhood Kidney Diseases
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• v.27 no.2
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• pp.105-110
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• 2023

Purpose: To analyze electrocardiograms (ECGs) of patients with a salt-losing tubulopathy (SLT) and to determine the frequency and risk factors for long QT and arrhythmia. Methods: A total of 203 patients aged <19 years with SLT, specifically Bartter syndrome and Gitelman syndrome, who had a 12-lead ECG were included in this retrospective study. We analyzed the presence of an arrhythmia or prolonged corrected QT (QTc) on ECGs obtained for these patients. Demographic and laboratory data were compared between patients with abnormal and normal ECG findings. Results: Out of the 203 SLT patients, 38 (18.7%) underwent electrocardiography and 10 (40.0%) of 25 patients with inherited SLT had abnormal ECG findings, including prolonged QTc and arrhythmias. The abnormal ECG group had significantly lower serum potassium levels than the normal group (median [interquartile range]: 2.50 mmol/L [2.20-2.83] vs. 2.90 mmol/L [2.70-3.30], P=0.036), whereas other serum chemistry values did not show significant differences. The cutoff level for a significant difference in QTc interval was serum potassium level <2.50 mmol/L. One cardiac event occurred in a 13-year-old boy, who developed paroxysmal supraventricular tachycardia and underwent cardiac ablation. No sudden cardiac deaths occurred in this cohort. Conclusions: The incidence of ECG abnormalities in patients with inherited SLT was 40.0%, whereas the ECG screening rate was relatively low (18.7%). Therefore, we recommend ECG screening in patients with inherited SLT, especially in those with serum potassium level <2.50 mmol/L.

• Clinical and Experimental Pediatrics
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• v.50 no.5
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• pp.462-468
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• 2007

Purpose : The purpose of this study was to analyze the changes of the late potential of Signal- averaged electrocardiography (SAECG) and Electrocardiography (ECG) parameters during follow up of those who had taken surgical repair of Tetralogy of Fallot (TOF). Methods : Nine patients who had taken surgical repair of TOF since 1985 checked SAECG and standard 12 leads ECG twice in 1999 and 2005 in Kyungpook national university hospital. We evaluated changes of QRS duration, QT interval and JT interval, QRS dispersion, QT dispersion and JT dispersion of standard 12 leads ECG and Filtered QRS (f-QRS), High frequency low amplitude potential (HFLA), Root mean square in terminal 40 ms (RMS) and Mean voltage in terminal 40 ms (MV) of SAECG between in 1999 and 2005. Results : There were significant decrease of JT dispersion ($101.11{\pm}50.11$ vs $71.11{\pm}22.61ms$, P< 0.05) and significant increase of HFLA ($24.67{\pm}13.19$ vs $32.89{\pm}14.21ms$, P<0.05). But there were no significant changes in other parameters. Conclusion : In repaired TOF patients, we evaluated ECG and SAECG to detect possible late complications such as tricuspid regurgitation, right ventricular enlargement, ventricualar arrythmia and sudden death. And there were significant changes of ECG and SAECG in some parameters (JT dispersion, HFLA). But to see the relationships between the changes of these parameters and the long term prognosis, we need to check more patients and longer follow-up.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.29 no.1
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• pp.377-382
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• 2005

This paper deals with productivity improvement of stevedoring system by pooling opertaions of transport vehicle at automated container terminal. Usually, in traditional container terminals, grouping operations of transport vehicle are applied for container crane because vehicle routing path is simple and vehicle assignment is easy. But this static assignment(SA) operation that arrsign vehicles to container crane ar apron reduces flexibility of vehicles. Therefore, This paper presented 4 dynamic assignment(DA) method to improve efficiency of vehicles. These 4 dynamic assignment method consider present situations of container crane such as sequence(Se), queue time(Qt), productivity(Pr), numeric of vehicle assignment(Nv), numeric of buffer(Nb) at vehicles assignment. At the results, dynamic assignment operation to consider Qt, Nv, Nb is most efficient and by next time, dynamic assignment operation to consider Se is superior more than static assignment operation. but, dynamic assignment operation to consider Pr or Qt of container crane only is inefficient than static assignment operation.

• Journal of Preventive Medicine and Public Health
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• v.39 no.6
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• pp.455-461
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• 2006

Objectives : Prolongation of the heart rate-corrected QT (QTc) interval has been reported to be associated with cardiovascular morbidity and mortality. However, few studies have examined the relationship between the QTc interval and cardiovascular risk factors in young healthy people, The aim of this study was to examine the associations between the QTc interval and cardiovascular risk factors in young healthy adults. Methods : This study was performed as part of the Kangwha study, which started in 1986, and is an on-going follow-up study on blood pressure and related cardiovascular risk factors. In follow-up examinations during 2005, cardiovascular risk factors, including anthropometrics, blood pressure, blood chemistry and carotid ultrasonography, were measured, and questionnaires on health behaviors completed by 127 men and 149 women aged 25 years. The QTc interval was measured on the resting 12-lead electrocardiogram using an automatic analysis program. Results : The mean QTc interval was significantly longer in women $(419{\pm}17ms)$ than in men $(405{\pm}17ms)$ (p<0.001). A significant positive correlation was found between the QTc interval and waist-hip ratio (p=0.030) in men. Women showed a positive correlation between the QTc interval and systolic blood pressure (p=0.017). On a multiple regression analysis, the QTc interval was positively associated with the waist-hip ratio in men (p=0.012) and with the systolic blood pressure (p=0.020) in women. Conclusions : In young healthy Korean adults, the QTc interval was independently associated with the waist-hip ratio in men and with the systolic blood pressure in women.

• Proceedings of the Korean Information Science Society Conference
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• 2005.11a
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• pp.586-588
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• 2005

WebDAV는 HTTP/1.1을 확장한 윕통신 프로토콜로서 인터넷을 통하여 다양한 콘텐츠의 비동기적인 협업 제작을 지원하기 위한 표준 하부구조를 제공한다. WebDAV명세를 지원하는 다양한 종류의 서버들은 사용자 상호간의 협업작업이 가능하게 해준다. 그리고 WebDAV 클라이언트는 서버와 HTTP 요청/응답 과정을 통하여 WebDAV 기능을 수행한다. 하지만 클라이언트 자체적으로 요청/응답 과정을 처리하는 것은 매우 복잡할 뿐만 아니라 비효율적이다. 따라서 WebDAV 기능을 잘 처리할 수 있는 클라리언트 라이브러리를 사용하는 것이 바람직하다. 본 논문에서는 WebDAV 클라이언트의 HTTP 요청/응답 처리를 위한 DAVon 클라이언트 라이브러리를 개발하였다. DAVon은 객체지향 기법으로 설계되어 C 라이브러리보다 편리한 API를 제공하고 리눅스 QT 라이브러리를 기반으로 구현되었다. 그리고 QT의 시그널/슬록 방식을 사용하여 HTTP 요청을 비동기적으로 처리함으로써 클라이언트의 병행성을 효율적으로 지원한다.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.622-627
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• 2003

The existing remote control system have some inherent disadvantage of direct control in the limit range. In some special cases, for example, a power apparatus, an unmanned factory, a nuclear factory, a security management system, the tele-operation is needed to control remote robot without limit space. This field is based on the Internet communication. Because the Internet is constructed all over the world. And it is possible that we control remote mobile robot in the long distance. In this paper, we developed a remote control system. This system is divided into two primary parts. These are local site and remote site. There are the moving robot and web server in the remote site and there is the robot control device in local site. The moving robot is moved by two stepper motors and the robot control device consists of SA-1100 micro controller and embedded Linux. And this controller is an embedded system. Public personal computer which is connected the Internet is used for the web server. The web server provides the mobile robot control interface program to the remote controller and captures the image for feedback information. In the whole system, a robot control device is connected with moving robot and web server through the Internet. So the operator can control the moving robot in the distance through the Internet.

• The Journal of the Korea institute of electronic communication sciences
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• v.10 no.4
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• pp.521-526
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• 2015

Research on how to use the biological characteristics of human to confirm the identity of the individual is being actively conducted. Electrocardiogram(: ECG) based biometric system is difficult to counterfeit and does not cause skin irritation on the subject. It can be easily combined with conventional biometrics such as fingerprint and face recognition to give multimodal biometric systems. In this thesis, biometric identification method analysing ECG waveform characteristics from Discrete Wavelet Transform(DWT) coefficients is suggested. Feature selection is performed on the 9 coefficients of DWT using the correlation analysis. The verification is achieved by using the error back propagation neural networks. Using the proposed approach on 24 subjects of MIT-BIH QT Database, 98.88% verification rate has been obtained.

• Journal of Veterinary Clinics
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• v.21 no.2
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• pp.219-228
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• 2004

Heart diseases related to conduction system can be occurred by primary defects in conduction system and by secondary to morphological heart diseases or drug toxicities. Multiple molecular defects responsible for arrhythmogenesis, including mutations in ion channels, cytoplasmic ion-channel-interacting proteins, gap-junction proteins, transcription factors and a kinase subunit, were found to be associated with the aetiology of primary cardiac conduction defects, especially inherited form. Despite a big progress in unveiling human arrhythmogenesis, conduction defects in dog has not been well studied except sudden death syndrome in German shepherd. In this review, molecular genetics in cardiac arrhythmogenesis, inherited human diseases associated with conduction defects and similar diseases in dogs will be discussed.

• Reproductive and Developmental Biology
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• v.34 no.3
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• pp.153-159
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• 2010

The 34 potently pig pheromonal odorants (1-32, 5755 & 7113) through structure-based virtual screening and ligand-based virtual screening method were selected and their ADMET and pharmacokinetics characters were evaluated and discussed quantitatively. The pheromonal odorants were projected on the following pre-calculated models, Caco-2 cell permeability, blood-brain barrier permeation, hERG inhibition and volume-distribution. From the results of in silico study, it is found that an optimal compound (31) either penetrating or have a little ($P_{caco2}$=-8.143) for Caco-2 cell permeability, moderate penetrating ability ($P_{BBB}$=0.082) for blood-brain barrier permeation, the low QT prolongation ($P_{hERG}$=1.137) for the hERG $K^+$ channel inhibition, and low distribution into tissues ($P_{VD}$=-5.468) for volume-distribution. Therefore, it is predicted that the compound (31) a topical application may be preferable from these based foundings.